The geology of Svalbard

The Geology of Svalbard

To Svalbard Colleagues

Geological Society Memoirs Series Editor A. J. FLEET

View of Ny-.&lesund settlement seen from the west with three mountain peaks, Tre Kroner, in the distance. The peaks are capped by Carboniferous strata unconformably resting on Early Devonian rocks. They are 30 km distant from the buildings, being foreshortened by the telephoto lens. The glacier from which they emerge as nunataks extends about 15 km nearer. The remaining 15 km just visible is the eastern, inner part of Kongsfjorden. To the right in the foreground is a raised, insulated and heated utiliduct supplying water from a small lake. Photo M. J. Hambrey, CSE 1962 (SP.941e).

View WSW from the old road quay at Ny Alesund, with Scheteligf]ellet in the centre right formed mainly of Carboniferous and Permian strata. Typical low cloud is creeping half way up the mountain from the right. The middle foreshortened low tundra with snow is characteristic raised beach or strandflat topography. The cliffs in the foreground usually about 5-10 m high form the coastline of the shallow bay, Thiisbukta, where in somewhat deeper water motorboats have a sheltered anchorage. The ice in the foreground is 'bay ice', which forms each winter and melts in the early summer. After a hard winter (probably in June) this bay ice is grounded in shallow water at low tide. In a few days it would disintegrate and drift away with tide. Photo M. J. Hambrey (SP631).

The Geology of Svalbard By W. B R I A N H A R L A N D

(University of Cambridge, UK)

Assisted by LESTER M. ANDERSON and DAOUD MANASRAH (CASP, UK) With contributions by NICHOLAS J. BUTTERFIELD (University of Cambridge, UK) ANTHONY CHALLINOR (deceased formerly University of Cambridge, UK) PAUL A. DOUBLEDAY (CASP, UK) EVELYN K. DOWDESWELL (University of Aberystwyth, UK) JULIAN A. DOWDESWELL (University of Aberystwyth, UK) ISOBEL GEDDES (CASP, UK) SIMON R. A. KELLY (CASP, UK) EDA L. LESK (CASP, UK) ANTHONY M. SPENCER (Statoil, Norway) CLARE F. STEPHENS (CASP, UK)

M e m o i r 17 1997 P u b l i s h e d by The G e o l o g i c a l Society London

THE GEOLOGICAL SOCIETY The Society was founded in 1807 as The Geological Society of London and is the oldest geological society in the world. It received its Royal Charter in 1825 for the purpose of 'investigating the mineral structure of the Earth'. The Society is Britain's national society for geology with a membership of around 8000. It has countrywide coverage and approximately 1000 members reside overseas. The Society is responsible for all aspects of the geological sciences including professional matters. The Society has its own publishing house, which produces the Society's international journals, books and maps, and which acts as the European distributor for publications of the American Association of Petroleum Geologists, SEPM and the Geological Society of America. Fellowship is open to those holding a recognized honours degree in geology or cognate subject and who have at least two years' relevant postgraduate experience, or who have not less than six years' relevant experience in geology or a cognate subject. A Fellow who has not less than five years' relevant postgraduate experience in the practice of geology may apply for validation and, subject to approval, may be able to use the designatory letters C Geol (Chartered Geologist). Further information about the Society is available from the Membership Manager, The Geological Society, Burlington House, Piccadilly, London W1V 0JU, UK. The Society is a Registered Charity, No. 210161.

Published by The Geological Society from: The Geological Society Publishing House Unit 7 Brassmill Enterprise Centre Brassmill Lane Bath BA1 3JN UK (Orders: Tel. 01225 445046 Fax 01225 442836) First published 1997 The publishers make no representation, express or implied, with regard to the accuracy of the information contained in this book and cannot accept any legal responsibility for any errors or omissions that may be made. 9 The Geological Society 1998. All rights reserved. No reproduction, copy or transmission of this publication may be made without written permission. No paragraph of this publication may be reproduced, copied or transmitted save with the provisions of the Copyright Licensing Agency, 90 Tottenham Court Road, London W1P 9HE. Users registered with the Copyright Clearance Center, 27 Congress Street, Salem, MA 01970, USA: the item-fee code for this publication is 0435-4052/97/$10.00. British Library Cataloguing in Publication Data A catalogue record for this book is available from the British Library.

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Contents

List of figures List of tables List of photographs Preface Acknowledgements Participants Conventions

ix ..~ Xln

5.4

Xln

5.5 5.6 5.7 5.8 5.9

XV

xvii ixx xxi

PART 1 Introduction

CHAPTER 6

CHAPTER 1 SVALBARD 1.1 Geographical names 1.2 Topography and bathymetry 1.3 The physical environment 1.4 The biota 1.5 Political history 1.6 The Spitsbergen Treaty 1.7 Settlements 1.8 Official publications

Northeastern Spitsbergen, Wilhelmoya and Hinlopenstretet Southwestern Nordaustlandet Kong Karls Land (with S. R. A. Kelly) Barentsoya, Edgeoya and Tusenoyane Hopen Correlation of four exploratory wells: Edgeoya and Hopen

3 7 8 10 11 11 13 13

6.1 6.2 6.3 6.4 6.5 6.6 6.7 6.8

Early work Stratal succession Subjacent metamorphic complex Late tectonic plutons Minor igneous bodies Summary of isotopic ages Structure of Nordaustlandet The Lomonosov Ridge in relation to Nordaustlandet

CHAPTER 7 CHAPTER 2 2.1 2.2 2.3 2.4 2.5 2.6

Early exploration 1858 to 1920 1920 to 1945 1946 to 1960 1960 to 1975 1975 onwards

CHAPTER 3 3.1 3.2 3.3 3.4 3.5

CHAPTER 4

4.4 4.5 4.6 4.7 4.8 4.9

16 16 16 18 19 20 21 23 23 25 29 31 37

Regional descriptions THE CENTRAL BASIN

Geological frame Van Mijenfjorden Group (Paleogene) Adventdalen Group (Cretaceous-Jurassic) (by S. R. A. Kelly) Kapp Toscana and Sassendalen Groups (Liassic-Triassic) (with I. Geddes) Biinsow Land Supergroup (Permian-Carboniferous) Tempelfjorden Group (Permian) with I. Geddes & P.A. Doubleday Gipsdalen Group (Permian-Carboniferous) with I. Geddes & P. A. Doubleday Billefjorden Group (Early Carboniferous) with I. Geddes & P. A. Doubleday Structure and development of Central Basin

CHAPTER 5 5.1 5.2 5.3

SVALBARD'S G E O L O G I C A L F R A M E

The space frame: Svalbard's structural frame The time frame The rock frame Tectonostratigraphic sequences Geotectonic interpretations

PART 2 4.1 4.2 4.3

OUTLINE HISTORY OF G E O L O G I C A L RESEARCH

EASTERN SVALBARD P L A T F O R M

Platform strata Igneous rocks Submarine outcrops

7.1 7.2 7.3 7.4 7.5 7.6 7.7 7.8 7.9 7.10

NORTHERN NORDAUSTLANDET

N O R T H E A S T E R N SPITSBERGEN

Geological frame Younger (cover) rocks Post-Permian deformation Ny Friesland plutons The Hecla Hoek Complex: the continuing debate Hinlopenstretet Supergroup Lomfj orden Supergroup Stubendorffbreen Supergroup: succession Stubendorffbreen Supergroup: genesis The Hecla Hoek Complex: mid-Paleozoic structure and metamorphism

77 80 83 86 91 93

96 96 96 104 105 106 106 107 108

110 110 112 112 112 113 116 118 121 125 128

CHAPTER 8 N O R T H W E S T E R N SPITSBERGEN

132

8.1 8.2 8.3 8.4 8.5 8.6

133 134 135 142 145 152

Cenozoic volcanic rocks of the Woodfjorden area Mesozoic, Permian and Carboniferous cover Liefde Bay Supergroup (Devonian) The 'crystalline' rocks of Northwestern Spitsbergen Structure Offshore geology (with P.A. Doubleday)

47 47 48 52 59 63 63 66 71 73 75 75 76 76

CHAPTER 9 9.1 9.2 9.3 9.4 9.5 9.6 9.7 9.8 9.9 9.10

Paleogene strata Mesozoic strata of Oscar II Land Late Paleozoic strata of Oscar II Land Early Paleozoic rocks Proterozoic strata of Oscar II Land Pre-Carboniferous rocks of Prins Karls Forland Structure of Oscar II Land (with P. A. Doubleday) Structure of Prins Karls Forland Structure of Forlandsundet Basin (with P. A. Doubleday) A tectonic interpretation of the West Spitsbergen Orogen: northern segment

CHAPTER 10 10.1 10.2

CENTRAL WESTERN SPITSBERGEN

SOUTHWESTERN A N D S O U T H E R N SPITSBERGEN

Paleogene strata Mesozoic strata in southwest Sorkapp Land

154 154 158 159 162 165 166 168 171 175 177

179 180 182

vi 10.3 10.4 10.5 10.6 10.7 10.8 10.9 10.10 10.11 10.12 10.13

CONTENTS Permian and Carboniferous strata of southern Spitsbergen Devonian strata Proterozoic strata of western Nordenski61d Land Proterozoic strata of western Nathorst and northwestern Wedel Jarlsberg Lands Early Paleozoic and Proterozoic strata of southwestern Wedel Jarlsberg Land Early Paleozoic and Proterozoic strata of Sorkapp Land Pre-Devonian correlation through southwest Spitsbergen Structure of western Nordenski61d Land Structure of western Nathorst Land Structure of Wedel Jarlsberg Land (with P. A. Doubleday) Structure of Sorkapp Land (with P. A. Doubleday)

CHAPTER 11

S O U T H E R N SVALBARD: BJORNOYA A N D SUBMARINE G E O L O G Y

11.1 11.2 11.3 11.4

Early work Geologic frame of Bjernoya Triassic strata of Bjornoya Late Paleozoic strata of Bjornoya (with I. Geddes) 11.5 Pre-Devonian strata of Bjornoya 11.6 Structural sequence of Bj~rnoya 11.7 Submarine outcrops 11.8 Submarine structure (with P. A. Doubleday)

PART 3

199 200 201

CHAPTER 17

201 205

~-~,~~,' nn 210 212 212 213 218 219 222 222

229 229 231 235 236 239 240

Vendian Vendian Vendian Vendian Vendian Vendian

time scale and correlation successions and correlation in Svalbard biotas environments international correlation palinspastic discussion C A M B R I A N - O R D O V I C I A N HISTORY

Cambrian-Ordovician Cambrian-Ordovician Cambrian-Ordovician Cambrian-Ordovician Cambrian-Ordovician

CHAPTER 15

time scale biotas and correlation sedimentary environments tectonic environments terranes and palinspastics

S I L U R I A N HISTORY

15.1 Silurian time 15.2 Silurian supracrustal events: sedimentation and tectonics 15.3 Silurian tectogenesis 15.4 Silurian petrogenesis of crystalline rocks 15.5 Silurian terranes, provinces and palinspastics 15.6 Sequence of Silurian (main Caledonian) events

17.1 17.2 17.3 17.4 17.5

244 244 246 248 249 252 254 257 260 260 264 266 268

17.6 17.7 17.8

D E V O N I A N HISTORY

Devonian time scale and correlation Devonian succession Devonian biotas ?Silurian and Devonian sedimentation Devonian tectonics The question of sinistral Paleozoic strike-slip faulting, transpression and transtension Sequence of events through Devonian time A Lomonosov conjecture

197

Precambrian time scales Pre-Vendian rock successions Pre-Vendian biotas (by N. J. Butterfield) Precambrian isotopic ages Tectonostratigraphic evidence for proto-basement Pre-Vendian correlation Palinspastic considerations V E N D I A N HISTORY

16.1 16.2 16.3 16.4 16.5 16.6 16.7 16.8

227

CHAPTER 14 14.1 14.2 14.3 14.4 14.5

191

PRE-VENDIAN HISTORY

CHAPTER 13 13.1 13.2 13.3 13.4 13.5 13.6

189

Historical Synthesis

CHAPTER 12 12.1 12.2 12.3 12.4 12.5 12.6 12.7

CHAPTER 16 183 187 188

CARBONIFEROUS-PERMIAN HISTORY

Early work Stratigraphic frame: Biinsow Land Supergroup Structural frame Carboniferous and Permian time scale Carboniferous-Permian sedimentary environments {1.~r, I . f"L~,..1,-.l~'~ ~ ,_,y ,_,~uu~) Carboniferous-Permian fossil record Carboniferous-Permian tectonic control of sedimentation (with I. Geddes) Carboniferous and Permian palaeogeology

289 289 291 291 296 299 303 306 309

310 310 312 314 316 318 324 328 335

CHAPTER 18 TRIASSIC HISTORY

340

18.1 18.2 18.3 18.4

340 343 344

18.5 18.6 18.7

Early work Structural frame Triassic rock units Triassic time scale and international correlation (with I. Geddes) Triassic biotas Sequence of Triassic environments (with I. Geddes) Triassic regional palaeogeology

350 353 356 36l

CHAPTER 19 J U R A S S I C - C R E T A C E O U S HISTORY

363

19.1 19.2 19.3 19.4

363 365 366

19.5 19.6 19.7 19.8

Early work Jurassic-Cretaceous structural frame stratigraphic scheme Jurassic-Cretaceous time scale and correlation (with S. R. A. Kelly) Jurassic-Cretaceous formations Jurassic-Cretaceous biotas Jurassic-Cretaceous events in Svalbard events (with S. R. A. Kelly) Svalbard in a Jurassic-Cretaceous regional context

CHAPTER 20 20.1 20.2 20.3 20.4 20.5 20.6 20.7 20.8 20.9

P A L E O G E N E HISTORY

Early work Structural and stratigraphic frame Paleogene time scale and correlation Paleogene biotas of Svalbard Paleogene sedimentation and tectonics Paleogene structures (with A. Challinor & P. A. Doubleday) Structural sequence Regional tectonic sequence Paleogene tectonosedimentary history

368 372 378 381 383 388 388 390 391 393 394 399 410 413 413

272 272 275 275 280 284 288

CHAPTER 21 21.1 21.2 21.3 21.4

N E O G E N E - Q U A T E R N A R Y HISTORY

Neogene--Quaternary time scale Plate motions (by C. F. Stephens) Deep structure of Svalbard Neogene-Holocene volcanism and thermal springs (by C.F. Stephens)

418 418 418 421 423

CONTENTS 21.5 21.6 21.7 21.8 21.9

Neogene and Pleistocene sedimentation (with C.F. Stephens) Neogene-Holocene uplift and erosion Glacial history of Svalbard: Neogene-Holocene (with C.F. Stephens) Pleistocene and Holocene surficial geology and geomorphic features Post-glacial sea-level and climatic changes

CHAPTER 22

22.1 22,2 22,3 22.4 22,5 22,6 22.7

PART 4 426 427 429 431 434

M O D E R N GLACIERS A N D CLIMATE C H A N G E (by E. K. Dowdeswell and J. A. Dowdeswell) 436

Introduction Modern ice cover Geophysical characteristics and ice dynamics Ice-ocean interaction Late Holocene glacial events and chronology Glaciers and climatic change Summary and conclusions

vii

436 436 438 442 443 444 445

23 23.1 23.2 23.3 23.4

APPENDIX: ECONOMIC G E O L O G Y Coal Petroleum (with A. M. Spencer) Metalliferous minerals Non-metalliferous minerals

449 449 251 253 254

I N D E X OF PLACE NAMES (by L. M. Anderson)

455

GLOSSARY OF S T R A T I G R A P H I C NAMES

463

REFERENCES

477

GENERAL INDEX

515

Figures Fig. 4.10 Geological map of Btinsow Land showing the distribution of Permo-Carboniferous formations (Btinsow Land Supergroup) Fig. 4.11 Summary of the stratigraphic schemes for Central Spitsbergen since 1950 Fig. 4.12 Schematic west-east stratigraphic profile showing lateral variations and structural controls on Carboniferous stratigraphy Fig. 4.13 Stratigraphic schemes for the Billefjorden Group Fig. 4.14 Simplified structural cross-sections of the Central Basin

CHAPTER 1 Fig. 1.1 Regional geographical setting of Svalbard Fig. 1.2 Principal islands and fjords of Svalbard Fig. 1.3 The 'lands' of Svalbard Fig. 1.4 Map showing the principal topographic features of Svalbard Fig. 1.5 Bathymetry of the western Barents Shelf Fig. 1.6 Prevailing surface currents of the Barents Sea and North Atlantic areas Fig. 1.7 Principal ice cover and valleys of Svalbard Fig. 1.8 Diagrammatic map to show boundaries of possible political interest Fig. 1.9 Map showing environmentally protected areas of Svalbard Fig. 1.10 Marine chart sheet coverage of Svalbard Fig. 1.11 Topographic and geological map coverage of Svalbard

12 12 14

Fig. 3.1 Svalbard in the Arctic (Polar projection) 23 Fig. 3.2 Generalized geological map of Svalbard 24-5 Fig. 3.3 Regions of Svalbard as used in this book for Chapters 4 to 11 25 Fig. 3.4 Principal discontinuities in Svalbard 26 Fig. 3.5 Major structural features of the western Barents Shelf 26 Fig. 3.6 Russian structural map of Svalbard 27 Fig. 3.7 Provisional time scale used in this book 28 Fig. 3.8 Svalbard chronometric record 30 Fig. 3.9 Tectonostratigraphic terranes of Svalbard 32 Fig. 3.10 (a) Simplified stratigraphy and geological evolution of Svalbard 39 (b) Schematic map of rock units and terranes 40 Fig. 3.11 Sequence of palinspastic reconstructions for the North Atlantic and Arctic from Cambrian to the present-day 41-2 Fig. 3.12 Summary of successive palaeolatitudes for Europe and North America for Silurian to Neogene time 43 Fig. 3.13 Plot of subsidence against time for western, central and eastern areas 44 CHAPTER 4

CHAPTER 6

CHAPTER 2 Fig. 2.1 Geological sketch map of Spitsbergen by A. G. Nathorst Fig. 2.2 Geological map of Spitsbergen by Hans Frebold

17 19

CHAPTER 3

Fig. 4.1 Reproduction of the Festningen profile as by Hoel & Orvin (1937) Fig. 4.2 Map of the Paleogene outcrops in the Central Basin Fig. 4.3 Stratigraphy of the Van Mijenfjorden Group Fig. 4.4 Geological map and cross-section of eastern Nordenski61d Land and Sabine Land Fig. 4.5 Geological map of the east coast of Spitsbergen from Agardhbukta to Hamburgfjellet Fig. 4.6 Geological map and cross sections of the Adventdalen Group in Wedel Jarlsberg Land and western Torell Lands Fig. 4.7 Geological map and cross sections of the Adventdalen Group in Sorkapp Land Fig. 4.8 Geological map and cross sections of the Adventdalen Group in Oscar II Land, Nordenski61d Land and Nathorst Land Fig. 4.9 Fence diagram showing the distribution and thickness variation of the Sassendalen and Kapp Toscana groups

49 50 51 54 55

56 56

58 60

65

66 72 73

CHAPTER 5 Fig. 5.1 Map of the eastern platform area of Svalbard showing the main place names and principal bathymetric features Fig. 5.2 Geological map of eastern Ny Friesland Fig. 5.3 Geological map of southwestern Nordaustlandet showing the known extent of Phanerozoic outcrops Fig. 5.4 Stratigraphical schemes for Permian and Triassic units of Nordaustlandet Fig. 5.5 Sketch map of Svenskoya, Kongsoya and Abeloya Fig. 5.6 Sketch map of Svenskoya showing principal topographic features and geology Fig. 5.7 Sketch map of Kongsoya showing principal topographic features and geology Fig. 5.8 Summary of schemes of rock units, and their ages, of Kong Karls Land Fig. 5.9 Correlation of the principal stratigraphic sections on Svenskoya Fig. 5.10 Correlation of the principal stratigraphic sections on Kongsoya Fig. 5.11 Proposed nomenclature for local rock units on Barentsoya and Edgeoya Fig. 5.12 Geological map of Barentsoya and Edgeoya Fig. 5.13 Interpretation of Raddedalen- 1 well (Edgeoya) Fig. 5.14 Interpretation of Plurdalen-1 well (Edgeoya) Fig. 5.15 Edgeoya and Barentsoya Triassic biostratigraphy Fig. 5.16 Generalized structural map of Barentsoya and Edgeoya, with structure contours for the top of the Barentsoya Formation Fig. 5.17 Geological map of Hopen and a longitudinal section along the island Fig. 5.18 Interpretation of Hopen-1 and Hopen-2 wells Fig. 5.19 Correlation of the Raddedalen-1, Plurdalen- 1, Hopen-1 and Hopen-2 wells

14

64

Fig. 6.1 Map of northern Nordaustlandet showing principal topographic features, ice-rock boundaries and major place names Fig. 6.2 Preferred names for rock units in Nordaustlandet and their approximate equivalents in Ny Friesland, with estimated thicknesses Fig. 6.3 Geological map of northwestern Nordaustlandet Fig. 6.4 Summary of isotopic ages from Nordaustlandet Fig. 6.5 Outline geological map of Nordaustlandet and adjacent areas of Ny Friesland

76 78 80 81 82 82 83 84 84 85 87 88 90 91 91

92 92 94 95

97

98 101 107 108

CHAPTER 7 Fig. 7.1 Topographic and place name map of Ny Friesland Fig. 7.2 Summary of the Hecla Hoek succession of Ny Friesland. Fig. 7.3 Generalized geological map of Ny Friesland outlining the distribution and subdivision of the Hecla Hoek Complex

111 114

115

x Fig. 7.4 Distribution of the Stubendorffbreen Supergroup in Ny Friesland Fig. 7.5 (a) Metamorphic rocks of the southern part of Ny Friesland (Lower Hecla Hoek) (b) M.B. Bayly's metamorphic zones as defined in Ny Friesland Fig. 7.6 Structural map of Ny Friesland Fig. 7.7 Diagrammatic cross-sections across Ny Friesland Fig. 7.8 Alternative structural interpretations across Ny Friesland

FIGURES

121

126 128 129 130

CHAPTER 8 Fig. 8.1 Geological map of NW Spitsbergen Fig. 8.2 Liefde Bay Supergroup units Fig. 8.3 Faunal divisions and lithological members of the Wood Bay Formation Fig. 8.4 Geological map of the Raudfjorden/Liefdefjorden area, Northwestern Spitsbergen, showing the distribution of the Siktefjellet and Red Bay groups Fig. 8.5 Schematic section showing the relationships between the units of the Siktefjellet and Red Bay groups Fig. 8.6 Caledonian basement rocks in northwest Spitsbergen Fig. 8.7 Generalized geological map of Biskayerhalvoya, northwest Spitsbergen Fig. 8.8 Principal structural elements (mainly Devonian) of northwest Spitsbergen Fig. 8.9 Map of central west Dickson Land Fig. 8.10 Generalized cross-section across northwest Spitsbergen, from the Albert I Land High to the Andr6e Land Basin Fig. 8.11 Structural profile across the Andr~e Land anticline between Gr~huken and Mushamna Fig. 8.12 Principal bathymetric features off northwest Spitsbergen

133 136 137

139 141 143 145 146 146

147 148 152

CHAPTER 9 Fig. 9.1 Topographic and place name map of Oscar II Land and Prins Karls Forland Fig. 9.2 Diagrammatic outcrop map of central west Spitsbergen Fig. 9.3 Geological map and stratigraphic section of the Ny-.~lesund coalfields Fig. 9.4 Summary of the Paleogene stratigraphic units in Forlandsundet Fig. 9.5 Fence diagram showing the stratigraphic relationships within the St Jonsfjorden Trough Fig. 9.6 Structural cross-section showing the major folds and thrusts in the Mediumfjellet-Lappdalen area Fig. 9.7 Alternative structural profiles across northern Prins Karls Forland to illustrate the different interpretations of the structure Fig. 9.8 Lithostratigraphic formations and geological map of south-central Prins Karls Forland Fig. 9.9 Simplified structural map and cross-sections of the Forlandsundet Graben Fig. 9.10 Schematic diagram of 'flower structure' within a convergent strike-slip fault zone

155 156 157 157 160 171

173 174

196 197

202 203 203

CHAPTER 11 Fig. 11.1 Bathymetric map of the western Barents Sea around southern Svalbard, with principal bathymetric features named 209 Fig. 11.2 Summary of stratigraphic schemes for Bjornoya 210 Fig. 11.3 Geological map of Bj~rnoya 211-2 Fig. 11.4 Summary plot of seismic velocity, porosity and estimated minimal subsidence rate 212 Fig. 11.5 Structure contour map of the base of the Roedvika Formation, with diagrammatic profile 213 Fig. 11.6 Schematic structural map of Bjornoya 220 Fig. 11.7 Geological map and sketch cross-section through basement rocks of southern Bjornoya 221 Fig. 11.8 Structure of the western Barents Sea showing the possible location of the Iapetus suture 223 CHAPTER 12 Fig. 12.1 Outcrops of pre-Vendian rocks (mainly Proterozoic) Fig. 12.2 Precambrian timescale comparing chronostratigraphic and chronometric scales Fig. 12.3 Correlation of pre-Vendian sequences of Ny Friesland and Nordaustlandet Fig. 12.4 Correlation of pre-Vendian sequences of the western terranes Fig. 12.5 Correlation of Precambrian sequences in the western, central and eastern terranes, with some age constraints Fig. 12.6 Map showing the distribution of proto-basement in Svalbard Fig. 12.7 Pressure-temperature plot for the metamorphic complex of Biskayer Peninsula Fig. 12.8 Correlation of East Greenland and Ny Friesland Proterozoic sequences Fig. 12.9 Schematic reconstruction of eastern Laurentia and Baltica for the period 1900-1600 Ma Fig. 12.10 Pre-Vendian aulacogen model showing the distribution of the Greenland, Barents and Baltica cratons Fig. 12.11 Global palinspastic reconstruction for Kanatia timeshowing the locations of rift margins and glacigenic deposits

228 229 230 231

236 237 238 240 240 241

242

176 CHAPTER 13 177

CHAPTER 10 Fig. 10.1 Topographic and place name map from Isfjorden to Sorkapp Fig. 10.2 Generalized outcrop map of central and southwestern Spitsbergen Fig. 10.3 Simplified tectonic map of central and southwestern Spitsbergen Fig. 10.4 Vendian geology of northwest Wedel Jarlsberg Land Fig. 10.5 Stratigraphic schemes for the Precambrian succession of southern Wedel Jarlsberg Land

Fig. 10.6 Comparison of stratigraphic schemes for southwest Spitsbergen Fig. 10.7 Correlation of Pre-Devonian units in southwest Spitsbergen Fig. 10.8 Structural map and representative cross-sections of Nordenski61d Land, illustrating the structure of Carboniferous to Cretaceous units Fig. 10.9 Simplified structural profile across the Midterhuken Peninsula Fig. 10.10 Schematic structural profile of northern Sorkapp Land

180 181 182 190 193

Fig. 13.1 Outcrop map showing the distribution of Vendian outcrops in Svalbard Fig. 13.2 Vendian biostratigraphy and isotopic variations of carbonate rocks Fig. 13.3 Correlation of Vendian successions in Svalbard Fig. 13.4 Secular variation in ~513Cplotted against stratigraphic depth (m) for the Varanger and Sturtian succession of Spitsbergen Fig. 13.5 Interpretation of Vendian environments from the successions of northeastern Spitsbergen Fig. 13.6 Vendian correlation chart for representative successions of Svalbard and adjacent areas of the North Atlantic-Arctic region

245 246 247

249 250

252

FIGURES Fig. 13.7 Correlation of the Vendian successions of East Greenland and northeast Svalbard 253 Fig. 13.8 Schematic palinspastic model for Vendian time showing the inferred positions of the Svalbard terranes and the postulated Iapetus Ocean 253 Fig. 13.9 Global palinspastic reconstruction for Rodinia time showing the distribution of Varanger glacigenic deposits 256

Fig. 16.9 Tectonic evolution and stratigraphic sequences in the Western, Central and Eastern Svalbard Precambrian to Devonian terranes Fig. 16.10 Geological provinces of the eastern part of the Canadian Arctic Archipelago and northern Greenland Fig. 16.11 Summary of strike-slip displacement along the major fault and shear zones of Svalbard to illustrate the possible amounts of sinistral displacement

xi

303 306

307

CHAPTER 14 Fig. 14.1 Cambrian and Ordovician rock units in contemporary nomenclature and classification Fig. 14.2 Map of Svalbard showing the distribution of Cambrian and Ordovician outcrops Fig. 14.3 Cambrian-Ordovician chronostratic time scale divisions with biostratigraphic correlations and estimated chronometric ages Fig. 14.4 Cambrian-Ordovician correlation chart for Svalbard Fig. 14.5 Approximate subsidence rates for the Cambrian-Ordovican sequence in Ny Friesland Fig. 14.6 Simplified geological map and representative profiles of the Motalafjella area (Oscar II Land) Fig. 14.7 Pressure-temperaturetime trajectory for the Motalafjella blueschist-eclogite complex Fig. 14.8 Cambrian-Ordovician tectonic events in Svalbard Fig. 14.9 Schematic correlation of North AtlanticArctic Early Paleozoic sequences Fig. 14.10 Schematic illustration of the CambrianOrdovician palinspastic configuration of Greenland and adjacent terranes according to the strike-slip hypothesis conjectured in this work Fig. 14.11 Ordovician palinspastic map

CHAPTER 17 257 258

259 261 265 267 268 269 269

270 270

CHAPTER 15 Fig. 15.1 Map of Svalbard showing the distribution of Silurian outcrops and areas of tectonism and metamorphism Fig. 15.2 Summary of Silurian time scales Fig. 15.3 Field sketch of the Stubendorff Mountains Fig. 15.4 Cartoon illustrating the elements in tectonic transitions in the Ny Friesland Orogen Fig. 15.5 Schematic profile of the pre-Red Bay Group structure as observed in Biskayerfonna-Holtedahlfonna terrane just south of Liefdefjorden Fig. 15.6 Quantitative petrographical classification of granitic rocks in Svalbard Fig. 15.7 Schematic illustration of terranes surrounding Greenland at approximately the beginning of Silurian time, with the closure of the Iapetus Ocean Fig. 15.8 (a) Late Ordovician to Early Silurian global palinspastic reconstruction, with glacigenic deposits; (b) Mid-Silurian palinspastic reconstruction

273 274 277 277

279 281

287

287

CHAPTER 16 Fig. 16.1 Outcrop map showing the distribution of Devonian deposits in Svalbard and locations of identified thermal events Fig. 16.2 Stratigraphic correlation chart for the (Devonian) Liefde Bay Supergroup of Svalbard Fig. 16.3 Devonian fossil fish reconstructions Fig. 16.4 Devonian fossil fish ranges Fig. 16.5 Distribution of Svalbard Devonian fish genera with time Fig. 16.6 Illustration of a Devonian landscape Fig. 16.7 Schematic diagrams to illustrate successive sedimentation patterns through Devonian time Fig. 16.8 True-scale cross-sections of fold and fault zones in the Devonian rocks of the Gronhorgdalen Belt, Eastern Boundary Belt and an EW cross-section from James I Land to the Balliolbreen Fault

290 292 293 294 295 296 297

302

Fig. 17.1 Map of Svalbard showing the distribution of Carboniferous and Permian rocks 311 Fig. 17.2 Chart illustrating successive classifications of rocks units 312 Fig. 17.3 Lithostratigraphic scheme for Carboniferous and Permian formations of the Bfinsow Land Supergroup 313 Fig. 17.4 Schematic map of Carboniferous and Permian structures 315 Fig. 17.5 Carboniferous and Permian time scale and biostratigraphy 317 Fig. 17.6 Some fossils recorded from Carboniferous and Permian formations of Svalbard 325 Fig. 17.7 Fence diagram illustrating lateral variations and tectonic controls on the Carboniferous stratigraphy 328 Fig. 17.8 Early Carboniferous lithofacies maps 329 Fig. 17.9 (a) Early Bashkirian lithofacies. (b) Moscovian lithofacies maps 331 Fig. 17.10 Gzelian lithofacies map 332 Fig. 17.11 (a) Asselian lithofacies. (b) Early Artinskian lithofacies maps 332 Fig. 17.12 Ufimian lithofacies 333 Fig. 17.13 Principal Carboniferous and Permian tectonic events 335 Fig. 17.14 International correlation of Carboniferous and Permian formations in the Arctic 336 Fig. 17.15 Carboniferous to Permian paleogeologic maps of the Barents Sea region 337-8 CHAPTER 18 Fig. 18.1 Outcrop map showing the distribution of Triassic deposits in Svalbard Fig. 18.2 Correlation chart to show the relationship of published Triassic stratigraphic names in Svalbard Fig. 18.3 Triassic structural framework Fig. 18.4 Triassic lithostratigraphic schemes for Svalbard Fig. 18.5 Sassendalen Group isopach map Fig. 18.6 Kapp Toscana Group isopach map Fig. 18.7 Localities and thickness of the Wilhelmoya Formation Fig. 18.8 Triassic time scales Fig. 18.9 Comparative zonation of Triassic Svalbard successions Fig. 18.10 Stratigraphic correlation chart Fig. 18.11 (a) Early, (b) Mid-(early Ladinian) and (c) Late Triassic sedimentary facies of Spitsbergen, Barentsoya and Edgeoya Fig. 18.12 Triassic sedimentation sequences on Barentsoya and Edgeoya Fig. 18.13 Regional Triassic tectonics Fig. 18.14 Comparison of Arctic shelf sequences in Svalbard and the Queen Elizabeth Islands plotted for the Tournaisian to Maastrichtian interval Fig. 18.15 Triassic palaeogeology of the Barents Sea. (a) Early to Mid-Triassic; (b) Late Triassic

341 342 344 346 347 348 349 351 352 353

357 359 359

360 361

CHAPTER 19 Fig. 19.1 Map of Svalbard showing the distribution of Jurassic and Cretaceous outcrops Fig. 19.2 Hydrocarbon potential and depositional environment of Triassic to Cretaceous rocks of Svalbard

364 365

xii

FIGURES

Fig. 19.3 Historical review of the principal stratigraphic schemes for the Jurassic and Cretaceous of Spitsbergen 366 Fig. 19.4 Jurassic and Cretaceous structural framework Fig. 19.5 Summary of the principal lithostratigraphic units of the Adventdalen and Kapp Toscana groups in Svalbard 367 Fig. 19.6 Jurassic-Cretaceous international time scale 369 Fig. 19.7 Summary of the biozonal schemes for Svalbard and the adjacent Barents Sea 370 Fig. 19.8 Biostratigraphic distribution of belemnite genera in Svalbard 372 Fig. 19.9 Summary of the Jurassic and Cretaceous stratigraphy of Svalbard and the adjacent Barents Sea 373 Fig. 19.10 Summary of the lateral development of the Helvetiafjellet Formation 375 Fig. 19.11 Fence diagram showing lateral variations in the Carolinefjellet Formation 376 Fig. 19.12 Map showing the distribution of JurassicCretaceous igneous rocks 377 Fig. 19.13 Summary of events in the Jurassic and Cretaceous history of Svalbard 381 Fig. 19.14 Lateral variation of the Agardhfjellet and Rurikfjellet formations across Spitsbergen 382 Fig. 19.15 Summary of structural and tectonic events in the Arctic in mid-Jurassic and mid-Cretaceous time 383 Fig. 19.16 Jurassic to Cretaceous palaeogeologic maps of the Barents Sea 384-5

CHAPTER 20 Fig. 20.1 Map of Svalbard showing the distribution of Paleogene deposits and deformation 389 Fig. 20.2 Sequence of classification of Paleogene deposits in the Central Basin 390 Fig. 20.3 Generalized Paleogene structural framework of Spitsbergen 391 Fig. 20.4 Paleogene time scale 392 Fig. 20.5 Successive interpretations of the age of Paleogene strata and events in Svalbard 393 Fig. 20.6 Map showing the geographic-stratigraphic distribution, preservation state and sedimentary facies of palynomorph assemblages 398 Fig. 20.7 Schematic cross-section of the northern part of the West Spitsbergen Orogen 399 Fig. 20.8 (a) Map showing the location of unpublished structural profiles of the West Spitsbergen Orogen 402 (b) Selection of unpublished cross-sections of the West Spitsbergen Orogen by A. Challinor 403-8 Fig. 20.9 Schematic model illustrating the various structural configurations within an area of strike-slip deformation 409 Fig. 20.10 Interpretation of the structural development of Paleogene structures in Nordenski61d Land 411 Fig. 20.11 Historical review of Paleogene tectonic models for Svalbard 411 Fig. 20.12 Paleogene time-scale 412 Fig. 20.13 Sequence of maps showing the motion of Svalbard relative to Greenland (fixed) for latest Cretaceous to Oligocene time 413 Fig. 20.14 Diagrammatic model for the Cenozoic sea-floor spreading, dextral strike-slip and transpression between Svalbard and Greenland 414

Fig. 20.15 Palaeogeologic map of Spitsbergen in Mid-Paleocene time Fig. 20.16 Paleogene palaeogeologic maps of Spitsbergen latest Paleocene to early Mid-Eocene

415 415-6

CHAPTER 21 Fig. 21.1 Neogene and Quaternary volcanics; Quaternary hydrothermal springs, seeps and microseismic zones Fig. 21.2 Neogene and Quaternary time scale Fig. 21.3 Bathymetric features and structures of the Norwegian-Greenland Sea and eastern Arctic Ocean Fig. 21.4 Present-day bathymetric structures in the North Atlantic Fig. 21.5 Map showing depth to basement in Spitsbergen as defined from aeromagnetic data Fig. 21.6 Map of the Bockfjorden area indicating the locations of hydrothermal springs Fig. 21.7 Compositions of Neogene plateau lavas Fig. 21.8 Simplified profiles and Tertiary stratigraphy of the Western Barents Shelf Fig. 21.9 Summary of the Neogene units of the western Barents Shelf margin Fig. 21.10 Interpretation of the Neogene fluvial drainage pattern in the Barents Sea Fig. 21.11 Map of the Barents Sea delineating the main erosion areas from mid-Miocene to Recent Fig. 21.12 Summit-height map of Svalbard Fig. 21.13 Diagrammatic model of the chronology of the deglaciation pattern of the Western Barents Sea Fig. 21.14 Diagrammatic illustrations of patterned ground Fig. 21.15 Late Pleistocene stratigraphy of inner Isfjorden

419 420 420 422 423 424 424 426 427 427 428 429 430 433 434

CHAPTER 22 Fig. 22.1 Map of Svalbard with the distribution of the modern glaciers and ice caps Fig. 22.2 (a) Map of estimated precipitation over Svalbard; (b) Map of estimated equilibrium line altitude over Svalbard Fig. 22.3 Landsat satellite image of Nordaustlandet with the interpretation of ice-cap drainage basins inset Fig. 22.4 Airborne radio-echo sounding data from Austfonna, Nordaustlandet Fig. 22.5 Ice surface and bedrock profiles from radio-echo sounding of Nordaustlandet Fig. 22.6 Fast-flowing glaciers on Vestfonna Fig. 22.7 Photographs of a surge of Bakaninbreen, Spitsbergen Fig. 22.8 The terminus of a tidewater glacier Fig. 22.9 Photographs of constrasting iceberg morphology: (a) tabular, (b) irregular Fig. 22.10 Temperature records from 1912 Fig. 22.11 Mass balance records for three Spitsbergen glaciers Fig. 22.12 Energy balance model predictions of glacier response to future global warming Fig. 22.13 Oxygen isotope ratios from Lomonosovfonna since about AD 1200

437

438 439 440 441 441 442 443 444 444 445 445 445

APPENDIX Fig. 23.1 Plot of major wells in Svalbard Fig. 23.2 Mesozoic petroleum source-rocks of the Arctic

451 453

Tables Table Table Table Table Table

1.1 Geographical nomenclature for Svalbard archipelago 5 1.2 Arctic summers and winters in Svalbard 8 3.1 Precambrian chronometric scale 28 15.1 Eastern and western outcrops of Ny Friesland 276 16.1 Divisions of the Devonian 289

Table 17.1 Divisions of the Kapp Starostin Formation Table 17.2 Carboniferous and Permian sedimentation rates Table 19.1 Average of chemical analysis made by Tyrrell & Sandford (1933) Table 23.1 Deep well data for Svalbard

327 334 378 452

Photographs Interior of south central Spitsbergen from the air Cover Ny-Alesund and Tre Kroner ii Bay ice in Thiisbukta and Scheteligfjellet seen from Ny-A.lesund ii Comfortlessbreen and Aavartsmarkbreen from near the shore 1 Crevassed Monacobreen snout seen from the east 1 Small bergs in inner Kongsfjorden with Broggerhalvoya beyond 2 Late summer in mid Kongsfjorden with Kapp Mitra and the motor boat Salterella 2 Snow camp in southwest Lomonosovfonna looking down Wilsonbreen 45 Snow-capped mountains of Ny Friesland from northern Lomonosovfonna 45 Snow scooter in the middle reaches of Tryggvebreen, Ny Friesland 46

Tracked amphibious vehicle hauling sledges at Draken, Ny Friesland Camp on Nordenski61dkysten, a strandflat on the west coast of Spitsbergen Camp by Siktefjellet on raised beach north of Liefderfjorden The motor boat Arctoceras equipped for living aboard and working ashore The motor boat Salterella helped on her way through pack ice A safe anchorage for easy access ashore below Alkhornet Routine boat passage through Smeerenburgfjorden en route to the north The motor boat Salterella in north Liefdefjorden anchored off Erikbeen Access up Hannabreen from Liefdefjorden with signs of the end of summer

46 225 225 226 226 447 447 448 448

Preface 'I think that we shall have to get accustomed to the idea that we must not look upon science as a "body of knowledge", but rather as a system of hypotheses; that is to say, as a system of guesses or anticipations which in principle cannot be justified, but with which we work as long as they stand up to tests, and of which we are never justified in saying that we know they are "true" or "more or less certain" or even "probable".' Karl A. Popper (From a paper that Popper read in 1934 when his Logik den Forschung was in proof. It was published in English in the new appendices of his Logic of Scientific Discovery 1959, p. 317).

This work attempts to present the geology of Svalbard in some detail, arranged systematically as a definitive study and so reflecting the present conjuncture of research. It may thus meet the needs of specialists with information on related fields or of any geoscientist wanting an indication of what is known about this key region. Spitsbergen (peaked mountains), the name earlier referred to the whole archipelago. It is now replaced by the name Svalbard (cold coasts), within which Spitsbergen is the principal landmass. Spitsbergen alone is about the size of Switzerland and the whole archipelago a little less than the area of Scotland. Geologically it has the wealth in variety and complexity in stratigraphy and structure no less than these classic areas. Moreover with an international history and present treaty status many nations have participated in research so the geological literature currently comprising far more than 3000 publications is widely scattered and rapidly increasing. There are indeed excellent published geological outlines, but no comprehensive work. Part 1 of this work is introductory, setting the stage. Chapter 3 in particular presents the principal geological conventions used throughout and outlines the main geological features and tectonic hypotheses. Part 2 divides Svalbard into eight somewhat arbitrary regions/sectors which are described with minimal interpretation. The rock successions are described briefly from the top down as observed, and the structures are outlined and to some extent illustrated. Part 3 interprets historical events and environments from oldest to youngest in successive time-slices. Part 4 comprises an appendix on economic geology and four alphabetical lists (place names, stratigraphic names, references and general index). Small type has been used throughout the text for detail that may be skipped when only the main argument is of interest. My interest in the project stems from about 50 years of research in many aspects of Svalbard geology with some 50 colleagues and collaborators listed below. However this book purports to be an objective study of contributions from international sources. Where there are differences of opinion alternative views are presented. Obviously, however, no single person could comprehend the whole literature nor avoid some personal bias when making a coherent synthesis that has been thought through. These objectives would take more than a life-time to fulfil. This work is presented as a contemporary statement in the spirit of the quotation at the head of this preface. By venturing conjectures and exposing them freely in graphic form as well as in the text it is intended that they shall be subject to critical assessment. Lack of appropriate evidence does not vitiate an hypothesis nor can abundant supporting evidence establish it. Only contradictory evidence provides effective criticism. This work presents a challenge and a platform for further research and will be superseded in the normal course of science. The philosophy behind this study is that all geological data may be integrated in space and time, that is stratigraphy in the broad sense. This regional synthesis is offered as a contribution to Earth history. It is a two way interaction. Understanding of process enables and demands the interpretation of historical data and the attempt to understand history leads to further modifications in the theory of the Earth. For example: the attempt to make sense of the field data led to early hypotheses of continental drift; of cooling and heating of the mantle with regional subsidence and uplift; of compression leading to lateral escape, transpression and transtension; of large scale paleo-strike-slip of former provinces and allochthonous terranes; and of global Vendian glaciation.

This is a personal synthesis at the conclusion of work epitomizing a journey that began for me in Spitsbergen on graduation in 1938. I have been privileged as a student and teaching officer in a great University and as a member and Fellow of an ancient Cambridge College. These positions require specified duties in teaching and administration, but with freedom to pursue investigations whenever and wherever they may lead, provided the necessary resources can be found. I came into a culture where the older generation worked out their own research as individuals with little or no organized cooperation. After two abortive research lines I decided in 1948 both to attempt to tie up some unfinished work in Spitsbergen and at the same time to try out a pattern of cooperative research with our students. All I have learned about research was gained through such interaction and that is why I dedicate this work to those colleagues. Some, hardly junior, have long achieved distinction. About 400 persons have in diverse ways contributed to our joint enterprises. I draw attention to the early decades when fieldwork involved long boat journeys to Spitsbergen and then transport by small open boats, manhauled sledges and always much pack-carrying to the study area. Equipment was primitive and conditions often harsh. We thought ourselves fortunate indeed to share the experience of our predecessors in Svalbard exploration. I mention only two colleagues. Colin B. Wilson worked with me in N y Friesland contributing greatly to the work in Chapter 7. His contribution, first in our systematic survey of Ny Friesland and later on his private solo excursions by small boat with outboard, carrying sledges and supplies from Longyearbyen round the northwest to N y Friesland where he recorded exemplary observations across enormous distances. His motivation was the shear joy of discovery and only with difficulty was he persuaded to prepare work for publication. His death in 1959, not in Spitsbergen, but by an accident in Cambridge, deprived us of a remarkable investigator. C. John B. Kirton a brilliant first year student was killed in 1958 by a flying stone while holding a fossil at a new locality on a mountain later named after him. A service was held in 1959 at his remote grave and memorial cairns were built nearby and by the shoreside base. He represents the best in our university tradition. Our research group was never an official university project and we paid our way as best we could in the early days, contributing personally. The need for independence led to the formation of Cambridge Spitsbergen Expeditions, (later Cambridge Svalbard Exploration). This then led to the formation of the Cambridge Arctic Shelf Programme to give more security of employment and to spread our interests so as not to compete for limited funds in Britain or Norway. Finally I acknowledge one colleague, my wife Elisabeth, who in the early years looked after our family taking domestic responsibility single handed. In the middle years she assisted in Svalbard on 13 field seasons and has latterly given invaluable support to my writing of this work for which I alone must bear full responsibility. W. B. Harland July 1997

Department of Earth Sciences University of Cambridge Downing Street Cambridge CB2 3EQ

Acknowledgements Two kinds of acknowledgement relate to the research and to this publication. First paying tribute to those to whom the book is dedicated the research has benefited from the participation of many colleagues during 45 field seasons as well as in Cambridge. They contributed greatly to my education and determination to write this book. It may be of interest to other Svalbard geologists to note who have published from this experience. In list A those names with asterisks worked on Svalbard material for their research degrees, others participated, some over long periods. It would, however, be wrong to think only of the geologists whose reward was in their work. We depended throughout on logistic support. Of the hundred or more who supported the work in this way list C names those who took responsibility for more than one season, for example captaining boats. More than a hundred geology undergraduates joined as assistants and many have gone on to distinguish themselves. They often asked the most penetrating questions, made unlikely observations and were rewarding companions. Whereas the above thanks are for my own personal indebtedness to those who have shared in the work I gladly acknowledge the immense debt due to the larger scientific community whose published work is the basis of this book as may be noted from the list of publications cited. At the same time I should declare that by no means have the extensive files of CSE and CASP unpublished work been abstracted here. I remembered only what seemed relevant to the arguments. Nevertheless to have traversed the ground myself enabled the literature to be better appreciated. For help with the many aspects of the book it is both a pleasure and a duty to acknowledge the following: D. Manasrah's patient committal to disc of my scribble and good tempered acceptance of the need for innumerable revisions. L. M. Anderson helped manage the later stages of the book, executing most of the figures, listing place names and checking the whole for submission on disc. Both were employed by CASP on this work, (Cambridge Arctic Shelf Programme, West Building, Gravel Hill, Huntingdon Road, Cambridge C B 3 0 D J ) . Whereas I drafted most of the text and sketched most of the figures others contributed of their expertise as indicated in

the chapter headings. The late Dr A. Challinor gave permission to include the serial cross sections of the West Spitsbergen Orogen from his dissertation and later CSE reports (Section 20.6); D. I. M. Macdonald, Chief Geologist of CASP, supported this work throughout and seconded CASP staff at different times to this project. I. Geddes helped with the proofs. The place name list was compiled by Mr L.M. Anderson The lexicon of stratigraphic names begun in the fifties was abbreviated and checked recently in co-operation with W. K. Dallmann (Norsk Polarinstitutt Geologist and Chairman of the SKS) The more comprehensive bibliography (the basis of the reference list here) has a long history beginning with the earliest research. Managed for many years as a card index by K.N. Herod it was in due course computerised initially by R. A. Scott (CASP) and subsequently updated at regular intervals with the continuing help of D. Manasrah (CASP), and E. L. Lesk, Information Officer in CASP, who scanned new literature for me through this work. Publications were listed as met in the work and not sought out for a comprehensive bibliography. Unless otherwise stated in the captions, the figures were devised and sketched by me and then executed on disc by those who have initialled the diagrams, mainly L. M. Anderson, C. F. Stephens, S. R. A. Kelly, D. Manasrah and P. A. Doubleday. M. J. Hambrey, P. W. Webb and N. I. Cox provided most of the supplementary photographs that appear as the frontispiece and on the cover page for each of the four parts of the book. At a late stage in preparation of the manuscript I owe much to help from those who made useful improvements, especially to M. J. Wells (University College London) for correcting my Norwegian (and English), to F. Cooley (CASP) for checking most of the Russian transliterations in the reference list. The remaining mistakes would not be due to any failure on their parts. Named referees contributed significantly: in addition to A. M. Spencer's contribution in the Appendix, P. F. Friend, A. J. Martin and J. R. Parker suggested where improvements could be made. Finally the work has benefited from the professionalism of the staff of the Geological Society Publishing House in Bath, particularly the Staff Editor Angharad Hills.

(A) Geologists accompanying Cambridge field parties (and/or) who have had Svalbard research published * K. C. Allen L. M. Anderson K. A. Auckland * D. J. Batten * M. B. Bayly * D. E. T. Bidgood G. S. Boulton S. H. Buchan * H. J. Campbell * A. Challinor * C. Croxton * J. L. Cutbill * M. Dettmann J. A. D. Dickson P. W. Ditchfield E. K. Dowdeswell J. A. Dowdeswell * M. Dowling P. Doyle I. J. Fairchild * C. L. Forbes * R. A. Fortey * P. F. Friend

* M. D. Fuller * R. A. Gayer I. Geddes * D. G. Gee E . R . Gee * D. J. Gobbet A. Hallam M . J . Hambrey M. Head A . P . Heafford W . G . Henderson K . N . Herod * D. W. Holliday * W. T. Horsfield * K. Howells N . F . Hughes * P. F. Hutchins * L. K a n a t S . R . A . Kelly A . H . Knoll J. Laing U. Lehmann B . E . Lock

J. Lowry S . R . Lu D . I . M . Macdonald * A. J. M c C a n n * J. R. H. McWhae * G. M. M a n b y * A. M a n n * D. Masson-Smith * P. I. M a t o n * M. Moody-Stuart * A. P. Morris J . E . Odell * J. R. Parker C . A . G . Pickton * G. Playford * D. J. W. Piper S . P . Price M. Quest P . F . Rawson A . B . Reynolds W. Schwarzacher R . A . Scott * D. G. Smith

. . .

xvm M. P. Smith I. Snape 9 H. Spall C. F. Stephens K. Swett

ACKNOWLEDGEMENTS F. Thiedig R . S . W . Thornley C. Townsend G. Vallance R . H . Wallis

* P. Waddams * C. B. Wilson T . S . Winsnes N . J . R . Wright R . T . Wu

* Svalbard research students at one time

(B) Some of those who contributed to the field work and later in other ways M. J. Allderidge T. R. Astin P. B. H. Bailey M. H. P. Bott D. D. Clark-Lowes A. P. R. Cooper L. E. Craig T. A. Davies

J . G . Elbo N. Golenko G . E . Groom B. Harte E . M . Himsworth C . A . Jourdan R. Mason D . P . McKenzie

B. Moore M.J. O'Hara P . C . Parks C . V . Reeves O . P . Singleton J . C . Tippen F . J . Vine P . T . Warren

(C) Logistic leaders (e.g. boat captains) for more than one season R. A. Browne M. F. Chantrey N. I. Cox

W . D . H . Fairbairn R N J. H Gammage A . H . Neilson

A. C. Smith M. Tuson

Participants W. B. HARLAND

Department of Earth Sciences, University of Cambridge, Downing Street, Cambridge CB2 3EQ, UK L. M. ANDERSON

CASP, West Building, Gravel Hill, Huntingdon Road, Cambridge CB3 0DJ, UK D. MANASRAH

CASP, West Building, Gravel Hill, Huntingdon Road, Cambridge CB3 0DJ, UK N. J. BUTTERFIELD

Department of Earth Sciences, University of Cambridge, Downing Street, Cambridge CB2 3EQ, UK A. CHALLINOR (DECEASED)

Department of Earth Sciences, University of Cambridge, Downing Street, Cambridge CB2 3EQ, UK P. A. DOUBLEDAY

CASP. Present address: Amerada Hess Ltd, 33 Grosvenor Place, London SW1 X7HY, UK E. K. DOWDESWELL

Centre for Glaciology, Institute of Geography and Earth Sciences, University of Wales, Aberystwyth, Cardigan SY23 3DB, UK J. A. DOWDESWELL

Centre for Glaciology, Institute of Geography and Earth Sciences, University of Wales, Aberystwyth, Cardigan SY23 3DB, UK I. GEDDES

CASP. Present address." 1 School Close, Keevil, Trowbridge BA14 6SB, UK S. R. A. KELLY

Consultant with CASP, 10 Belvoir Road, Cambridge CB4 1JJ, UK E. L. LESK

CASP, West Building, Gravel Hill, Huntingdon Road, Cambridge CB3 0DJ, UK A. M. SPENCER

Statoil, Forushagen, 4035 Stavanger, Norway C. F. STEPHENS

CASP. Present address." Amoco (UK), Amoco House, West Gate, London W5 1XL, UK

Conventions Geological conventions employed throughout the work are treated in Chapter 3. These include the international time scale, principles for lithostratigraphic nomenclatures, the uses of some technical terms and the descriptive names for Svalbard structures. Place names are explained in Chapter 1 and listed in Part 4.

Acronyms in common use

Authority It is intended that any positive statement be supported by a reference at the end of the paragraph or subsection. If none it may be assumed either that the statement is common knowledge or that it is the original contribution (opinion) of this work. The names of up to three authors may be cited in the text and 'et al.' generally refers to four or more.

CSE: Cambridge Spitsbergen Expeditions, Cambridge Svalbard Exploration. CASP: Cambridge Arctic Shelf Programme. GSSP: Global stratotype section and point. IKU: Continental Shelf Institute, Trondheim. lUGS: International Union of Geological Sciences. NP: Norsk Polarinstitutt. SKS: Stratigrafisk Komit6 for Svalbard.

Use of contemporary nomenclature and compass orientation

Contractions in figures where space is critical

Transfiteration

-fjt (-fjellet); -fdn; fin (-fjorden); -fja (-fjella); -bn (-breen)

The Norwegian alphabet places symbols o and 6 ~t a~ at the end whereas they are placed here as though unmodified in the English language alphabetical order. For Chinese: Pinyin For Cyrillic: The system used was jointly recommended by the Permanent Committee on Geographical Names (PCGN) for British Official use and the United States Board on Geographical Names (USBGN), as revised in 1970 and 1972. It is used in the Times Atlas of the World, the Scott Polar Research Institute and the Geographical Names Division of the US Army Topographic Command, which has published perhaps the most comprehensive gazeteer of the FSU. The ISO system has advantages but requires the addition to normal type of accurate diacritical symbols unfamiliar in the west.

Time conventions Three-letter abbreviation of age names follow Harland et al. (1990), see Chapter 3.2. Formal use of subscript numbers 1, 2 & 3 = Early, Mid- and Late, which are not abbreviated. Ma is the usual symbol for the age in millions of years as also ka for thousands of years before present (BP).

In recording earlier work, unless original wording is quoted (in quotes), the present usage (for example of place and stratigraphic names) is generally substituted. Original names may be added in parentheses. Compass directions for earlier geological ages are expressed in the present orientation without implication as to what was the ancient orientation.

Rock units U, M & L upper, middle and lower for rock units only. 'Thickness' in metres is not added to numbers i.e. 100m to indicate 100m thick unless otherwise specified.

Lithologies Lst, dst, sst, slst, sh, cgl (conglomerate), qi (quartzite); aren. (arenaceous); dol (dolomite-except. dst); unto. (unconformity, unconformable).

Use of stratigraphic nomenclature (as explained in Section 3) The problem of divergent stratigraphic nomenclature and classification has been met by a discussion arriving at a conclusion generally early in each historical chapter. That discussion, often seemingly of miniscule interest, may then be confined to that particular section. The conclusions may be applied in the rest of the work both in earlier or later parts. Therefore, the reader who finds a different scheme employed and is possibly irritated thereby, should find the reasoning behind such a choice in a section in each of the historical chapters. The Stratigraphic Glossary may help.

PART 1 Introduction Chapter 1 Chapter 2 Chapter 3

Svalbard, 3 Outline history of geological research, 16 Svalbard's geological frame, 23

Mid-season view of the glaciers Comfortlessbreen (on the left) and Aavartsmarkbreen (beyond). The rocks are Early Vendian with Varanger tillites. Stratigraphic sections are generally worked along the glacier margins either by porterage from the shore (in this case Egelskbukta) or by sledge from the interior. Photo M. J. Hambrey (SP. 455).

Late season view from the east over the terminal crevassed glacier Monacobreen. In this case access up the glacier is almost impossible because the lower reaches are deeply crevassed and the glacier terminates in ice-cliffs in inner Liefdefjorden. The glacier beyond offers an easy route westward. Photo P. W. Webb, CSE 1989.

View from Ossian Sarsfjellet at the eastern end of Kongsfjorden towards the mountains of Broggerhalvoya which are reflected in the fjord. The intervening fjord carries a scatter of small bergs which have calved from the glacier cliffs of Kronebreen and Kongsbreen respectively to north and south of the photographer. The concentration of ice depends on wind and tide and is navigable with care in a slow moving boat. The small bergs melt rapidly in the summer. Photo M. J. Hambrey (SP96.122) 1996.

The CSE motorboat Salterella in mid-Kongsfjorden seen when looking out to sea with the landmark K a p p Mitra to the right where the rocks are Caledonian metamorphosed basement of pre-Vendian rocks. This is a late summer scene in an outer fjord. Snow on land and floating ice have gone. Weather generally deteriorates at this time so this is unusually a calm evening scene. Eider duck are flying and on the water. Photo P. W. Webb, CSE 1989.

Chapter 1 Svalbard W. B R I A N 1.1 1.1.1 1.1.2 1.1.3 1.2 1.3 1.3.1 1.3.2 1.3.3 1.3.4 1.3.5 1.3.6 1.4 1.5 1.6 1.6.1 1.6.2

Geographical names, 3 Principal islands and fjords, 3 The lands, 7 Norwegian place names, 7 Topography and bathymetry, 7 The physical environment, 8 Latitude and daylight, 8 Marine influences, 8 Weather, 8 Sea ice, 8 Snow and ice cover, 10 Frozen ground, 10 The biota, 10 Political history, 11 The Spitsbergen Treaty, 11 Administrative consequences of the Treaty, 11 Strategic consequences of the Treaty, 11

An introduction to Svalbard is as necessary for a geoscientist as for any other student of the archipelago. The section on geographical nomenclature is illustrated by maps which are designed to locate many of the commonly used names. These and others are listed at the end of the volume where additional names used later are referred to. The regional context of Svalbard is shown in Fig. 1.1. The present-day physical environment is mentioned, but treated more fully in Chapters 21 and 22.

HARLAND 1.6.3 1.6.4 1.7 1.7.1 1.7.2 1.7.3 1.7.4 1.7.5 1.7.6 1.7.7 1.8 1.8.1 1.8.2 1.8.3 1.8.4 1.8.5

The section on the present-day Svalbard biota is not by a specialist for specialists, but is intended to list those organisms commonly encountered in the field and of interest to most workers. The political and treaty considerations are interwoven and have sometimes left the Norwegian administration in an ambivalent position. Happily however the resources forthcoming from the petroleum industry to the nation has enabled the administration to fulfil its responsibility admirably and latterly without the pressures from the Cold War. Svalbard for its size has a small population, less than 4000 concentrated in relatively few settlements, but numbers are augmented by summer arrivals of construction/maintenance staff, tourists, students and scientists, while the residents often take their summer holidays on the mainland. The environmental threat from this expanding seasonal population presents one of the most serious challenges, while at the same time tourism is replacing coal mining as the principal economic resource. Provision of shipping facilities supplemented by air travel is transforming the economy, which however still requires substantial subsidy. The international community has generated more than 3500 geoscientific publications of which about 2500 are listed in the references. The official publication series are outlined at the end of this chapter. This work attempts to encompass the present geological nature of Svalbard and to interpret its history. It is mainly concerned with evidence from above sea level and this may be justified in part by some more recent interpretations of the Spitsbergen Treaty which claims for Svalbard not more than about 4 nautical miles offshore. The immense area of the submarine Barents Sea floor, the exploration of which resulted in enormous resources, is not treated here except for occasional mention. That would require another work on this scale and by another author. A recent convenient survey of what is known was provided by A. N. Nystad (1996) on the geology and petroleum resources of the Barents Sea; but as with so much knowledge obtained industrially, references to sources are not given. However this volume is mainly concerned with published information together with original thinking.

1.1

Fig. 1.1. Regional geographical setting of Svalbard, with typical maximum and minimum limits of pack ice. Simplified and redrawn from Harland (in press) Norway. Svalbard in Encyclopedia of Worm Regional Geology, fig. 1.

Economic/political consequences of the Treaty, 11 Environmental consequences of the Treaty, 12 Settlements, 13 Longyearbyen, 13 Sveagruva, 13 Ny-Alesund, 13 Barentsburg, 13 Pyramiden, 13 Other settlements, 13 Manned Norwegian radio and meteorological stations, 13 Official publications, I3 Bathymetric charts, 14 Topographic maps, 14 Geological maps, 15 Thematic maps, 15 Scientific serials of the Norsk Polarinstitutt, 15

1.1.1

Geographical names Principal islands and fjords

The archipelago, whose geology is the subject of this work, lies on the northwest corner of the Barents Shelf 650 km north of Norway.

4

CHAPTER 1

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SVALBARD The name Spitsbergen was given by the Dutch captain, Barents, who is generally credited with the modern discovery of the islands in 1596 and after whom the Barents Sea is named. Barents did not know that the name Svalbard (cool coast) was mentioned in the Islandske Annaler in A D 1194 and in the Landndmabbk (approximately AD 1230) from Viking exploration. It was supposed that this archipelago was the northern land referred to, although it was only much later that a clear distinction was made between Spitsbergen and Greenland. Also Russian hunters are claimed to have built huts in the fifteenth century and possibly earlier (Baron 1986). The name Spitsbergen refers to the pointed mountain peaks that the main island exhibits on approach from the sea. It had been used for the whole archipelago or for the main part of it excluding the outlying islands. Spitsbergen was the name for the whole archipelago in the Treaty of S6vres in 1920, and in the Spitsbergen Treaty, which came into effect in 1925. The main island had been known as West Spitsbergen. The name Svalbard was formally introduced by A. K. Orvin in Place Names of Svalbard (1942), by the Norsk Polarinstitutt (the Norwegian Polar Institute in Oslo) in the first systematic and descriptive gazeteer. In Place Names of Svalbard Spitsbergen was redefined to comprise the main group of islands, excluding the outlying islands Storoya, Kong Karls Land, Hopen (Hope island) and Bjornoya (Bear Island). The nomenclature was revised again (Hjelle 1970) so that Spitsbergen now refers only to the main island and excludes Nordaustlandet (North East Land), Barentsoya, Edgeoya, and Prins Karls Forland (Fig. 1.2). Place Names was supplemented in 1958. Until the Spitsbergen Treaty, which awarded the administration of the archipelago to Norway, the islands had been, in the words of Sir Martin Conway (1906), a 'no man's land'. There was no sovereignty and the principal competing nations first for whaling (1600 until the whale population was decimated around 1750) were Dutch and British; then for mineral rights American, British, Norwegian, Russian and Swedish. Scientific exploration went hand in hand with penetration beyond the coastline in a series of expeditions from Britain, (e.g. Scoresby 1820, Parry 1827), Norway (Keilhau 1831), Sweden (Torell 1859, Nordenski61d 1863, Nathorst 1910), Monaco (1899) with increasingly international participation. Consequently most prominent features were named in various languages. Whereas systematization and Norwegianization of older place names led to a single standard for scientific and cartographic description, for geological use once a rock unit name has been established, its original name remains unchanged except for change of rank etc. For example, in the literature before 1940 a common name in English for a fjord in the northwest was Red Bay. This was Norwegianized to Raudfjorden in i940 but the name Red Bay Conglomerate etc. still stands even if changed to Red Bay Formation or Group. Place names of Svalbard (Anon 1942) is a mine of historical information as well as a systematic Norwegianization of place names, and some principal geographical suffixes from that work are listed below. In addition to names for physical features (islands, mountains, glaciers, fjords etc.) the larger areas of Svalbard are divided into lands which are convenient for descriptive purposes (Fig. 1.3). Place names used in this work are listed at the end of the volume with figure numbers of some maps where they may be found. It is generally a scientific convention (as in this work) to follow the official geographical nomenclature of the Norsk Polarinstitutt (Table 1.1). Geological nomenclature will, as far as possible, follow generally recognized international principles taking into account recommendations of the Stratigraphic Committee for Svalbard (SKS). Even when discussing early work present nomenclature is generally employed here. Until about the middle of the nineteenth century there was little exploratory interest in the land. Indeed the prime concern was exploiting marine wealth. Fjords, anchorages and coastal hazards were the main concern. Thus the names of the principal accessible fjords were of great use in navigation. The Place Names of Svalbard recounts their early history. Therefore Fig. 1.2 also plots the present nomenclature of islands and coastal waterways.

5

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Table 1.1. Geographicalnomenclativefor Svalbard

Present nomenclature

1942-1960

pre- 1942*

Svalbard

Svalbard

Spitsbergen or Spitsbergen and Bjornoya

Spitsbergen and associated islands

Vestspitsbergen

Treaty 1925 West Spitsbergen?

Nordaustlandet

Nordaustlandet

North East Land

Barentsoya

Barentsoya

Barents Island*t

Edgeoya

Edgeoya

Edge Island*:~

Prins Karls Forland

Prins Karls Forland

Prins Charles Forland~w

Storoya

Storoya

Great Island

Kong Karls Land

Kong Karls Land King Charles Landw

Hopen

Hopen

Hope Island

Bjornoya

Bjornoya

Bear Island

* Originally in many languages. t Willem Barents, leader of Dutch expeditions 1594 to 1597. $ After Thomas Edge, early seventeenth century English whaler. wSeen by Barents and later named for Charles, Prince of Wales and later King of Britain and Ireland. [[Although discovered at least as early as 1617 by T. Edge this name was proposed by Petermann after Karl I (1823-91) King of Wtirttemberg.

Fig. 1.4. Map showing the principal topographic features of Svalbard, approximate locations of mountains are indicated by triangles with elevation in metres. Ice-cover in white is demarcated by dotted lines.

SVALBARD

1.1.2

7

The lands

The smaller islands need no further classification, but Spitsbergen and Nordaustlandet are now divided into lands for general descriptive purposes. These are not political units and have no precisely defined boundaries. Some names are as old as the island names in use and in many forms before the separate islands were distinguished as, for example, Ny Friesland. Other areas have been designated to complete the modern mosaic with the names of the Norwegian royalty, as for example Olav V Land which was introduced after the publication of Place Names o f Svalbard as in Fig. 1.3. The boundaries shown on Fig. 1.3 are diagrammatic and have no authority. In this work Ny Friesland will continue to describe the area which includes much of Olav V Land. Indeed for geological description Svalbard is classified in this work into sectors that are the descriptive Chapters 4 to 11 and also into terranes. These divisions are peculiar to this work. They are explained in Chapter 3.

1.1.3

Norwegian place names

Since 1942, with the publication of Place Names o f Svalbard, all official names have been Norwegianized: descriptive names being translated; proper names being preserved and usually each is combined with a geographical term. The last one or two letters of the term indicate the definite article, which in Norwegian syntax may be omitted, but in international and especially geological application the name should be indivisible. The plural form may modify the suffix. The common terms used as suffixes in place names are listed here. Mountains and hills, etc.: berget, fjellet, haugen, kammen, kollen, nuten, piggen, ryggen, tinden, toppen. Valleys, passes: dalen, passet. Plains etc.: sletta, vidda, oyra, flya, steinen (stone). Glacial: corrie, glacier, icefield: botnen, breen, fonna, jokulen, morene. Rivers and streams: elva bekken. Lakes, tarns: vatnet, laguna, tjorna, tjernet. Coastal inlets: hamna, pollen, bukta, vftgen. Coastal promontories: halvoya, huken, neset, odden, pynten, tangen, kapp. Shore: stranda. Water: sjoen (sea or lake), fjorden, sundet, flatet (sea bottom). Submarine features: banken, renna, flaket. Shoal, reef and skerry: grunnen, revet, skja~ret. Islet, island: holmen, oya. Settlement, mine, hut, cabin: byen, gruva, hytta, varden (landmark or cairn). Similarly the Norwegian geographical terms for north, northern etc. may constitute the first element in the place name thus: aust, austre; nord, nordre; sor, sore; vest, vestre. There remain a number of (descriptive) names which stand on their own e.g. Lykta, Eplet, Krokodillen. Happily these are often brief. The geological use of place names is discussed in Chapter 3. In maps and diagrams where space may be critical, contractions and abbreviations of the suffix are useful as -fjt for -fjellet, -fja for fjella, -fdn- for fjorden, -bn for -breen.

1.2

Topography and bathymetry

The northwestern margin of the European continental lithosphere comprises the Barents Shelf (Fig. 1.5). Extending northwards from Norway and northwestern Russia, the shelf is covered by the Barents sea except at the northwestern margin where the Svalbard archipelago, and further east Franz Josef Land emerge. The northern margin of the shelf is marked by the continental slope down to the Polar Ocean Basin. The western margin of the shelf similarly terminates along the oceanic Norwegian Greenland Sea.

Fig. 1.5 Bathymetry of the western Barents Shelf. Isobaths (in metres). (simplified from the map of Western Barents Sea Bathymetry, 1: 1 500 000, Norsk Polarinstitutt, Oslo, 1989).

Within the Barents Sea water depths rarely exceed 400 m. In the ocean basins they plunge rapidly from 500 m to 2000 m. On the shelf the bathymetry reflects Neogene and Quaternary history with a subdued drainage pattern. The topography of Svalbard, while reflecting the detailed geological structure which determines many contrasting land forms, shows certain general features. Sea-level changes have eroded and then exposed large tracts of nearly flat land or raised beach. A typical coastline consists of low cliffs seldom exceeding 10m and a coastal plain (strandflat) of variable width behind which steep mountains rise.

8

CHAPTER 1

The mountain peaks all fall within a general summit envelope representing an uplifted and warped peneplane almost regardless of the attitude of the strata, typically about 1000m. Land sculpture is a continuation of glacial erosion resulting in steep cliffs, valleys and glaciers. Other mountain contours typically result from a cold-desert environment with steep scree slopes and cliffs, where the rocks are resistant, giving little opportunity for vegetation to become established. Soft rocks give a more subdued landscape. The variety of land forms is typical of the Arctic as illustrated by Thor6n (1969)

1.3 1.3.1

The physical environment Latitude and daylight

The main islands lie between 76 ~ and 81~ Many distinctive features of this Arctic environment derive from the angle of incidence of solar radiation (Table 1.2; Kosak 1967 p. 99).

1.3.2

Marine influences

Svalbard is a relatively small archipelago and the climate is influenced by two sources of surface ocean water: (i) the West Spitsbergen Current, is the northern-most remnant of the Gulf Stream moving relatively warm water northwards along the west coast; (ii) the East Spitsbergen Current brings cold water and packice southwestwards east of Spitsbergen and the eastern islands. These currents meet off Sorkapp and the cold water is deflected and continues northwards between the warmer current and the coast, often carrying pack-ice with it, and causing fog (Fig. 16). On the western approaches the upper Atlantic layer of approximately 200-900 m in depth has a fairly uniform temperature of about 3~ whereas the bottom layer may be about - 1.0~ The tides range between about 2 m for spring and 1 m for neap except where restricted by land.

1.3.3

Fig. 1.6. Prevailign surface currents of the Barents Sea and North Atlantic areas, abstarcted from V. Hisdal (1985, fig. 12, p. 21) Geography of Svalbard.

is about 300-400mm (with a maximum of about 1000mm), most of which falls as fine snow or rain in summer and autumn. In summer the low humidity, cold land and warm air interact, often causing dense fog and low cloud over the glaciers and ice filled waters. In winter it is usually clear. The summer air temperature at sea level averages about 4-5~ and in winter about - 1 2 C ~ and commonly down to - 2 0 ~ in the west. Temperatures are lower towards the north and east. Summer temperature may rise to 10~ the extreme range may be - 5 0 ~ to +22 ~ There is usually some wind, which may be strong locally, especially in long fjords with direct access from inland ice. Mirages, haze, ice blink and white-out are all common.

Weather

Annual precipitation is low. In the east it is almost all snow and may be as low as 10 mm, per year. On the west coast the average

Table 1.2. Arctic summers and winters in Svalbard Latitude

80~ 79~ 70~ 66.5~

Number of days of continuous Daylight

Darkness

137 107 70 23

123 94 55 0

1.3.4

Sea ice

There is an inexhaustible supply of pack ice (often some years old) drifting from the polar basin with the East Spitsbergen Current. It depends for its subsequent distribution mainly on the marine currents but often and unpredictably on winds. It melts slowly in the warmer waters. The old, thicker, harder ice is a more serious factor in shipping especially when it drifts round the south of Spitsbergen and then northward along the west coast. On the other hand the annual freezing and thawing in the fjords provides a bay ice (never exceeding a metre in thickness) that melts rapidly, becoming rotten in early summer. A third floating hazard are the icebergs that come from calving glaciers. Larger bergs occur in many fjords and beyond,

Fig. 1.7. Principal ice cover and valleys of Svalbard. The ice-covered areas shown on the map are extremely generalized. Glaciers etc. are numbered black circles and valleys are numbered rectangles, each are listed in alphabetical order. Glaciers: (1) Aavatsmarkbreen; (2) Aust Torellbreen; (4) Balderfonna; (5) Barentsjokulen; (6) Bivrastfonna; (7) Borebreen; (8) BrSsvellbreen; (11) Chydeniusbreen; (12) Comfortlessbreen; (14) Dahlbreen; (15) Digerfonna; (16) Doktorbreen; (17) Dunerbreen; (19) Eidembreen; (20) Esmarkbreen; (21) Etonbreen; (23) Forstebreen; (24) Fridjovbreen; (26) Glitnefonna; (27) Gronfjordenbreen; (30) Hansbreen; (31) Hellefonna; (32) Hinlopenbreen; (33) Holmstrombreen; (34) Holtedahlfomla; (35) Hornbreen; (38) Isachsenfonna; (40 Kongsvegen; (41) Kronebreen; (42) Kvalbreen; (43) Kvitoyjokulen; (45) Leighbreen; (46) Lilliehookbreen; (47) Lomonosovfonna; (49) Maudbreen; (50) Mittag-Lefflerbreen; (51) Monacobreen; (53) Nansenbreen; (54) Nathorstbreen; (55) Negribreen; (56) Nordbreen; (57) Nordenski61dbreen; (58) Nordmannsfonna; (60) Olsokbreen; (61) Oslobreen; (63) Penckbreen; (64) Poulabreen; (65) Raudfjordenbreen; (66) Recherchebreen; (67) Renardbreen; (68) Rimfonna; (70) Samarinbreen; (71) Sefstrombreen; (72) Sjettebreen; (73) Smeerenburgbreen; (74) Sorbreen; (75) Sorkappfonna; (76) Storbreen; (77) Strongbreen; (78) Stubendorffbreen; (79) Sveabreen; (80) Terre Glac6e Russe; (81) Tunabreen; (83) Ulvebreen; (84) Ursafonna; (85) Uversbreen; (87) Valhallfonna; (88) Vasilievbreen; (89) Vegalfonna; (90) Venernbreen; (91) Vest Torellbreen; (92) Veteranen; (93) Veternbreen; (94) Vonbreen; (95) Von Postbreen; (98) Wahlenbergbreen; (99) Werenski61dbreen. Valleys: (1) Adventdalen; (3) Berzeliusdalen; (5) Colesdalen; (7) Dicksondalen; (8) Dyrdalen; (10) Forkdalen; (12) Gipsdalen; (13) Grondalen; (15) Kjelstr6mdalen; (17) Plurdalen; (18) Purpurdalen; (21) Reindalen; (22) Rijpdalen; (24) Sassendalen; (25) Semmeldalen; (28) Vestfjorddalen; (30) Woodfjorddalen.

SVALBARD

9

10

CHAPTER 1

long after the bay ice has melted. There is an increased supply of bergs from calving in the summer when glacier cliffs are undercut by warmer water. Their distribution is then a product mainly of tides rather than winds at least for the larger and deeper bergs. Figure 1.1 plots the extreme limits of pack ice in summer and winter (see Lunde 1965).

1.3.5

Snow and ice cover

In winter thin snow cover is general with bare patches and thick drifts. This melts throughout the summer leaving bare ice covering about 60% of the whole area above sea level. The larger islands all have ice caps from which glaciers flow, many reaching the sea (Fig. 1.7). The larger icefields are true ice caps, as in Nordaustlandet; the smaller are of 'highland ice' in which the subglacial topography is reflected in the surface contours of the ice. Most mountains also contain independent valley and corrie glaciers.

1.3.6

Frozen ground

Permafrost is defined as permanently or, more accurately, perennially frozen ground. The term is used in different senses. It is most usefully taken to mean that where seasonal melting at the surface occurs a distinctive active zone is separated from the permafrost by the permafrost table. Two terms, not in common use and of Russian origin, may be noted. Pereletok is a mass of anomalous frozen ground within the active zone, and talite is a mass of anomalous unfrozen ground within the permafrost. The formation, temperature, and depth of permafrost are the result of a complex interplay between the microclimatological conditions, the surface cover and the rock beneath, as are the movements that take place within the active zone to form many distinctive types of patterned ground (soil polygons). The sum of all these effects through many years yield a temperature curve with depth from which paleotemperatures may be inferred (section 21.8.4). Permafrost does not occur beneath large bodies of water or ice, so that the undersurface of frozen ground reflects all the above circumstances in a complex manner. In Spitsbergen it is said to have an average depth of 300 m and on Bjornoya only 60 m. Any disturbance of the equilibrium may lead to local phenomena such as pingos, and to frost heaving of man-made structures if adequate precautions have not been taken.

The contemporary (evident) biota (typically visible) Vertebrates Mammals Arctic fox, Alopex lagopus Reindeer, Rangifer tarandus platyrhychus (Musk ox, Ovibos moschatus, recently extinct in Svalbard) Polar bear, Ursus maritimus Seals: hooded, Crystophora cristata; harp, Phoca groenlandica; ringed, Phoca hispida; bearded, Erignathus barbatus Walrus, Odobenus rosmarus Whales: sperm, Physeter eatodon; killer, Orcinus orca; blue, Balaenoptera musculus; white (beluga) Delphinapterus leucas; narwal, Monodon monoceros; minke, Balaena aeutorostrata Birds Diver: red-throated, Gavia stellata Petrel: fulmar, Fulmarus glacialis Geese: barnacle, Branta leucopsis; pink-footed, Anser brachyrhynclus; brent, Branta bernicla Ducks: eider, Somatenia mollissina; king eider, S. spectabalis Waders: purple sandpiper, Calidris maritima; ringed-plover, Charadrius hiaticula; turnstone, Arenaria interpres; sanderling, Calidris alba; grey phalarope, Phalaropus fulicarius Passerine: snow bunting, Plectrophenax nivalis Skuas: arctic, Stercorarius parasiticus; long tailed, S. longicaudus; great, S. skua Gulls: kittiwake, Rissa tridactyla; glaucous, Larus hyperboreus; great black-back, L. mar&us; Sabine's, L. sabini; ivory, Pagophila eburnea Tern: arctic, Sterna paradisaea Auks: puffin, Fratercula arctica; little, Plautus alle; black guillemot, Cepphus grylle; Brtinnich's guillemot, Uria lomvia; common guillemot, Uria aalge Svalbard ptarmigan, Lagopus mutus hyperboreus Fish Arctic char, Salvelinus alphinus Bullhead, Cottus gobio Capelin, Mallotus villosus Cod, Gadus morrhua; burbot, Lota lota Halibut, Reinharditius lippoglosoides Shark: Greenland, Somniosus; basking, Cetorhinus maximus Echinoderms Echinoids, Stronglocentrotus cf. droebachiens& Asteroids Ophiuroids Crinoids

1.4

The biota

Flora and fauna reflect the above physical conditions. The land-based biota is fragile. About 160 species of flowering plants and a few other species occupy low ground and flourish as the snow cover recedes in the short summer, often with spectacular flowers. Grasses may exceed the 15 cm height of dwarf birch and willow. Vegetation directly supports a variety of insects, reindeer and ptarmigan and indirectly the arctic fox. Summerhayes & Elton (1928) made an early study. The marine biota is perhaps the more remarkable. In winter, marine life continues, evident at the surface only by seal, walrus and the predatory polar bear; females hibernate in the snow. Bears number around 5000. With melting of the bay ice in summer, upwelling currents rich in nutrients coupled with continuous daylight generate a prodigious marine food chain exploited by many millions of migrant birds as well as by seal and bear. The birds nest on land and fertilize rich vegetation locally. Ptarmigan overwinter, and occasionally snow bunting and sand piper. The land mammals belong only to three species, fox, reindeer and the polar bear which lives largely off sea ice; voles are recorded at Grumantbyen. A selective list of the more evident Svalbard species follows. Plants, birds, reindeer and bear are protected.

Arthropods Crustaceans Barnacles, Balanus balanoides Crabs and crayfish Ostracodes Arachnoids Spiders and mites Myriapods Insects Spingtails Flies: mosquito; chironomid midges; dragonfly; dameselfly; hoverfly; dipterids Beetles Annelids (oligochaets) Nematodes Molluscs Bivalves Astarte boreal&; A. montagui; A. elliptica; Thyasina flexuosa; Chinocardium ciliatum; Serripas groenlandicus; Macoma calcarea; Lyosima fluetuosa; Saxicava arctica; Mya truncata

SVALBARD

Gastropods Margarites groenlandicas; M. helicinus; Littorina saxatites; Natica clausa; Sipho togatus; Buccinum groenlandicus; B. glaciale; Lora bicanisata; black-winged pteropod, Clio Foraminifers (Nagy 1965) Inner fjords: Cassidulina reniforme; Elphidium clavatum Glaciomarine: Quinqueloculina stalkeri Cyanobacteria, Algae, Fungi and Plants Elvebakk & Prestrud (1996) catalogued 2885 Svalbard species*

Algae and cyanobacteria (1122 spp. recorded*): for example, Laminaria; Lithothamnion glaciale Lichens (593 spp. recorded*) Fungi (624 spp. recorded*) Mosses (373 spp. recorded*) Pteridophytes (7 spp.*) Equisetum arvense; Lycopodium selago Flowering plants-Angiosperms (no gymnosperms) (of 165 spp* 48 from Gaerevoll & Ronning, Flowers of Svalbard, 1980) Arenaria pseudofrigida; Arnica alpina; Braya purpurascens; Campanula uniflora; Cardamine nymani; Cassiope tetragona; Cerastium arcticum; Cochlearia officinalis; Draba corymobsa; D. lactea; Dryas octopetala; Erigeron humilis; Eriophorum scheuchzeri; Melandrium apetalum; M. augustiflorum; Mertensia maritima; Minuartia rubella; Oxyria digyna; Papaver dahlianum; Pedicularis dasyantha; P. hirsuta; Petasites frigidus; Polemonium boreale; Polygonum viviparum; Potentilla chamissonis; P. hyparctica; P. pulchella; Ranunculus hyperboreus; R. lapponicus; R. nivalis; R. pedatifidus; R. pygmaeus; R. sulphureus; Salix polaris; Saxifraga aizoides; S. cernus; S. cespitosa; S. flagellaris; S. hieracifolia; S. hirculus, S. nivalis," S. oppositifloria; S. rivularis; Silene acaulis; Stellaria crasspipes; S. humifusa; Taraxacum arcticum; T. brachyceras

1.5

Political history

In the middle ages, Norwegian kings claimed sovereignty over all land in the Arctic Ocean from Greenland to the Russian arctic islands. In the sixteenth century Spitsbergen became a whaling centre with ships from Holland, England, Denmark-Norway, France and Hamburg. The Dutch settlement, Smeerenburg, on Amsterdamoya was the largest, with peak populations estimated at 200 (or even 1200) persons in the summer. The Greenland whale (Balaena mysticetus) was nearly exterminated in the fjords by 1640 and whalers had to make their catch in the open sea. Of the many claims in the early seventeenth century King Christian IV of Denmark-Norway claimed sovereignty over Spitsbergen, in opposition to the British and Dutch. The Basques of SW France specialised in exploiting the Northcaper whale (Balaena glacialis) and in eighteenth century land-based whaling declined with the whale population, in favour of their migration routes in the open ocean until about 1800 when systematic whaling was finished. From about 1715 to 1850 Russian 'pomors' went to Spitsbergen and wintered to hunt polar bear, reindeer, fox and seal. Norwegians began sealing in Spitsbergen waters in the latter part of the eighteenth century and after c. 1850 without competition. The exploitation of coal began at the close of the 19th and beginning of the twentieth century (Gjelsvik 1968). Early claims to the sovereignty of Spitsbergen by Britain, Holland and Denmark were never followed up. However, competition for mineral wealth continued by many individuals and companies and the map of Spitsbergen was a patchwork of, often optimistic, claims. At the same time scientific exploration by British, French, German, Norwegian and Swedish bodies had heightened the interest in the sovereignty of the archipelago. Arlov (1994) described early negotiations between the Arctic nations in Oslo Conferences 1910 to 1914.

11

The Versailles Treaty makers set about clarifying competing national aspirations when they were arranging protectorates for former colonies. The result for Svalbard was the Spitsbergen Treaty. The history of exploitation in and around Svalbard is outlined more fully in the handbook by Arlov (1989, 1994) and in detail by Hoel (1966).

1.6

The Spitsbergen Treaty

The Spitsbergen Treaty was signed in Paris on 9 February 1920 and Norway assumed administrative responsibility on 14 August 1925. The original signatories were Australia, Britain, Canada, Denmark, France, India, Italy, Japan, Netherlands, New Zealand, Norway, South Africa, Sweden and USA. Other nations followed. e.g. USSR 1924, Germany 1925 later totalling more than 40 signatories. The treaty provides that citizens of these other nations shall enjoy the same rights as Norwegian citizens and as the Norwegian government with respect to access and economic activities on the islands and in the territorial waters. The 10 articles are indicated as follows: 1. 2. 3. 4. 5. 6. 7. 8. 9. 10.

defines by latitude and longitude, the boundaries of the archipelago, i.e. 74 ~ to 81~ and 10~ to 35~ provides equal fishing and hunting rights; guarantees free access to all waters and to all lands to all signatories; concerns the use of radio; concerns meteorological stations; recognises pre-Treaty rights of ownership and exploration; guarantees equal treatment of all signatories in future acquisition of land and mineral rights; outlines Norwegian intentions with regard to existing mining rights guarantees the neutrality of Svalbard; provides for Russia, then without government, to enjoy the same rights as other signatories.

Procedures for establishing existing claims were laid down under the jurisdiction of a commission to be nominated by the Danish Government (Sindballe 1927). Many other consequences followed from the Spitsbergen Treaty: administrative, strategic, economic/political and environmental.

1.6.1

Administrative consequences of the Treaty

Longyearbyen is the seat of the local administration where the Governor (Sysselmannen) has office and residence supported by police, now mainly helicopter borne. The mining inspector (bergmesteren) is responsible not only for mining operations but also for granting and refusing claim applications and for inspection of claims. The Norsk Polarinstitutt, under the Ministry of the Environment, is responsible for the geological survey of the island and is the Norwegian scientific (including geoscientific) armmainly concerned with the islands. Its former responsibility for topographic and bathymetric survey has been taken over by the Norwegian Mapping Authority (Statens Kartwerk). Appropriate ministries oversee other aspects of the administration such as postal services, radio communications, meteorological stations, building standards and conservation.

1.6.2

Strategic consequences of the Treaty

The strategic situation of Spitsbergen, so evident during the war years 1939 to 1945, and then subsequently in the Cold War between the Warsaw Pact and NATO has been neutralized (Article 9) so that no military establishments nor activities have been permitted.

12

CHAPTER 1

This was monitored by the Norwegian administration and from the Soviet settlements. The exception in World War II was mainly directed to the destruction and denial of facilities to the other side and to placing meteorological stations (Elbo 1952).

The Treaty did not foresee the complications of the off-shore exploration and exploitation of petroleum--it being largely concerned with mineral rights on land. Mineral claims on land were easily regulated by the mining inspector (Bergmesteren) agreeing approximately rectangular parcels each of 10km 2 area, not exceeding about 8 km in length and needing each to be staked, witnessed and claimed with specimens of a mineral to substantiate the claim. In effect this limits the seaward extension of any claim to within 4 nautical miles from a stake at the coastline. At that time, Norwegian maps showed the treaty area delineated by the bounding lines of latitude and longitude (e.g. 1 : 2M NP map of Svalbard 1958). This area was accepted by USSR maps which thus claimed a sector boundary from the NorwayUSSR frontier north along the line of longitude. It was shown to step eastwards between latitudes 74~ and 81~ to accommodate the Treaty area. Subsequently with the advent of subsea petroleum exploration and extended fishing claims far beyond the original 3 mile territorial waters it seemed that the Barents sea (i.e. on the continental shelf) was Norwegian or Soviet. Differences then emerged. On the one

hand Norway claimed a boundary to their part of the shelf based on the equidistant mid-line principle as applied elsewhere in offshore Europe. The USSR followed their meridional sector principle. This created a large disputed zone between the mid-line of the Norwegian government and the sector line of the former Soviet Union. On the other hand the extension of Norwegian continental shelf was held in Norway to override the earlier Treaty area so that the seas 4 miles offshore of the islands within the original latitude, longitude frame were regarded by Norway as outside Treaty jurisdiction. Norwegian maps no longer show this Treaty frame. All these matters have still to be finally resolved, while in the meantime a cooperative spirit in practical economic developments is taking place between Norway and Russia. Figure 1.8 illustrates the political problem accentuated by the economic consequences. The eastern margin of the Svalbard Treaty coordinate area (Long 35~ passes midway between Kvitoya (Svalbard) and Victoria Island (Russia) so that applying the preferred Russian sector principle the sector line running due north from the Norwegian-Russian international boundary on the mainland must be deflected eastwards, as in most Russian maps, to accommodate the Treaty coordinate area. This boundary favours Russia whereas the line median between the national coasts (as applied in the North Sea) passes in a NE direction before joining the same line between the two islands. On the other hand if Svalbard be defined as the archipelago limited to 4 nautical miles offshore, and if the continental shelf, to say the 500m isobath or 200 miles offshore, be applied most of the sea area in the archipelago would be Norwegian as is currently assumed.

Fig. 1.8. Diagrammatic map to show boundaries of possible political interest.

Fig. 1.9. Map showing environmentally protected areas of Svalbard. Redrawn from leaflet issued at Longyearbyen Airport and published by Norsk Polarinstitutt.

1.6.3

Economic/political consequences of the Treaty

SVALBARD

1.6.4

Environmental consequences of the Treaty

Another unforeseen consequence of the Treaty that allows virtually free access by the world's citizens without passport control has been the arrival of many nationalities in unprecedented numbers by cruise liners supplemented by the airport opened in 1975. The pressure on a fragile environment led to the establishing of national parks, bird sanctuaries and other environmental regulations. Thus while there is theoretical freedom of access this can only be permitted within the various necessary regulations and also within the limitations of very few tourist facilities except by sea. Figure 1.9 shows the national parks and nature reserves of Svalbard. Three national parks and three nature reserves, fifteen bird sanctuaries and three plant reserves have been established in Svalbard (see map). No waste may be emptied or left behind in any of the protected areas. The flora and fauna must be protected against injury and unnecessary disturbance. The use of cross-country vehicles is prohibited in the national parks and reserves. Nor are aircraft permitted to land in these areas without the permission of the Governor. From 15 May-15 August it is not permitted to travel within a distance of 300 meters from the edge of the bird sanctuaries. In the Moffen National Reserve all treaffic is forbidden from 15 May to 15 September, both dates inclusive. The ban also includes flying over the reserve at a height of less than 500 meters. All travel on Svalbard must take place in a manner that does not damage or unnecessarily disturb the natural environment. Special care should be exercised in the vicinity of lairs, breeding grounds and nesting sites. The use of motor vehicles is forbidden on thawed ground, and on ground covered by vegetation. There are special regulations for economic or industrial activity on Svalbard. These regulations are printed in the 'Regulations concerning Conservation of the Natural Environment in Svalbard', adopted by Royal Decree of 16 December 1983.

ropeway system long used for transporting coal from mine to loading dock has been replaced by road transport. The University in Svalbard (UNIS) was established in 1995 for one-year courses in Arctic disciplines (biology, geology, geophysics and technology).

1.7.2

1.7.3

Ny-.~lesnnd

Found on the south side of Kongsfjorden, coal was first mined by the Kings Bay Kulkompani A/S (KBKC) in 1917 until 1929 and resumed in 1947. Fifteen men were lost in an accident in 1948, but work continued. In 1960 modernization and extension of the mine was planned but was terminated on 5 November 1962 after an accident in which a whole shift of 21 men were lost. The small town (never more than 300 inhabitants) was then reduced to a small (international) scientific station with a Norsk Polarinstitutt research centre. It has a winter population of 20-30, greatly expanded in the summer by 200 or more visiting scientists and participants in conferences, courses etc.

Barentsburg

Settlements

There is no indigenous population. The principal settlements are based on Norwegian and Russian coal mines with a total population of about 3300 winter inhabitants. There is a large exchange in the summer.

1.7.1

Sveagruva

Located at Braganzavfigen at the head of van Mijenfjorden (in Bellsund) was mined for coal by a Swedish company from 1917 to 1925 when it was sold to SNSK. No mining was done for some years. The installations were destroyed in the war. Mining was resumed but abandoned in 1949 and extensive development (as a satellite mine for Longyearbyen) was planned in the late 1970s. Sveagruva is now the site of the main economic coal mining prospect in Svalbard with accessible reserves estimated at 25 million tonnes and contains one remarkable 5 m thick seam.

1.7.4 1.7

13

Longyearbyen

This is the seat of government of Svalbard and is situated at the head of Adventfjorden south of middle Isfjorden. The coal mine was founded by the American, J. M. Longyear, in 1904 and was worked till 1916. It was then sold to the Store Norske Spitsbergen Kulkompani A/S (SNSK). The earlier mines were in the mountain sides in Longyeardalen and most were destroyed during the 19391945 war. Post-war mines have been developed in mountains along the south side of Adventdalen and Adventfjorden. Coal is mined throughout the winter and stored at Hotellneset for summer shipping when mining ceases giving place to maintenance work. Output has been about half a million tons or less pa. Good facilities for mining personnel have been developed with school, hospital and modern city services. The services are mostly company property. However, the c o m p a n y is increasingly providing for tourists, expeditions and shipping on a commercial basis. The Longyear airport (opened 1975) with scheduled flights to Norway is situated at Hotellneset and there is a good internal road system. Longyearbyen is the principal base in Svalbard for the Norsk Polarinstitutt. The coal reserves, easily accessible from Longyearbyen are being rapidly e x h a u s t e d - the seams being high up in a series of mountains. At the same time Longyearbyen has been developed with an infrastructure, comparable to the best in Norway for a winter population of around 1200 including families. Whereas Sveagruva has coal reserves the investment in infrastructure in Longyearbyen could hardly be duplicated at Svea. The gantry

Located on the western side of Gronfjorden south of the entrance to Isfjorden, is the principal Russian settlement based on a coal mine. It was founded in 1919 by De Russiske Kulfelter. Extensive building was carried out by a Dutch company between 1921 and 1926 who sold it to the Soviet organization Arktikugol in 1932. In the 1930s the settlement was the largest in Spitsbergen. It was destroyed in the Second World War. As the Russian 'Capital' with consul, scientific offices etc. it recently had a population of more than 1000, now 950. Its original reserves have been exploited and mining is extending, by arrangement, into the neighbouring Norwegian claim area. Its economic viability is in question.

1.7.5

Pyramiden

Located at the head of Billefjorden (from northern Isfjorden) was originally a Swedish concession and has been owned by Arktikugol since 1934 [19267]. Construction work began in 1938. The population of about 650 is largely Ukranian.

1.7.6

Older settlements

Earlier settlements based on coal mines and now discontinued include Grumantbyen (FSU, west of Adventfjorden), M u s h a m n a (Norwegian) east of Adventfjorden, Tunheim (Norwegian) on the northeast coast of Bjornoya.

1.7.7

Manned Norwegian radio and meteorological stations

These include the principal station for shipping at Kapp Linn~, at the mouth of Isfjorden, operated from Longyearbyen; also

14

CHAPTER 1 lr~

~

2Ts

/6 ~

/12"

h5 ~

118~

I

'

I

[24 ~

~27 ~

\30 ~

\33 ~

510 80*

0

z~

C>

521

80

79 ~

78 ~

77*

504

/ 76~

76 ~

3G

509

[~501 7 4 o-

0

502 12~ i10o

115o

j20o

Polarinstutt, from catalogue.

at N o r d h a m n a on the north coast of Bjerneya, and at Hopen. Telecommunication from all Norwegian settlements is integrated into the Norwegian system.

publications

Scientific literature on such a small remote area as Svalbard has multiplied not only because of its inherent interest but by virtue of the participation of groups from many nations. A selected bibliography of geoscientific publications appears in part 4 of this volume. Here the the range of official publications is outlined.

1.8.1

Bathymetric

charts

As is customary, charts are under frequent revision while detailed surveys proceed to more remote areas. 12 charts are issued by the N. P (Fig. 1.10). Most other charts are derived from this information. Hydrographic survey is now the responsibility of Statens Kartverk.

1.8.2

Topographic

k.~

1o0

115"

D20 1: 40, 000

118~

/

2G

1:500 000 Sheets

121~

124~

127~

Svalbard 1" 100 000 Sheets

j25o

Fig. 1.10. Sheet lines of charts as originally published by Norsk

Official

4G~

75*

506

1.8

,~, ~ ,

A4 A5 A6 A7 A8 B4 B5 B6 B7 B8 B9 B10 Bll B12 C4 C5 C6 C7 C8 C9 C10 Cll C12 C13 D3 D4 D5 D6 D7 D8 D9

Vasahalveya Magdalenefjorden Krossfjorden Kongsfjorden Prins Karls Forland Reinsdyrflya Woodfjorden Eidsvollfjellet Tre Kroner St. Jonsfjorden Isfjorden Van Mijenfjorden Van Keulenfjorden Torellbreen Mosselbukta Asgardsfonna Austfjorden Dicksonfjorden Billefjorden Adventdalen Braganzav~gen Kvalv&gen Markhambreen Serkapp Storsteinhalveya Gotiahalveya Lomfjordhalveya Vaigattfjorden Hinlopenbreen Negribreen Agardhfjellet

D20 E1 E2 E3 E4 E5 E6 E7 E8 E9 El0 Ell E12 E13 F2 F3 F4 F5 F6 F9 F10 Fll G2 G3 G4 G5 G7 G14 H3 H7 J3

Bjernoya (1:40 000) Sjueyane Nordenski61dbukta Rijp~orden Wahlenbergfjorden GustavAdolf Land Wilhelmoya Kapp Payer Barentsjekulen Freemansundet Guldalen Kvalpyntfonna Tuseneyane H~eya Repeyane Duvefjorden Austfonna Vibebukta Br&svellbreen Berrheia Stonebreen Deltabreen Foyneya Leighbreen Isispynten Isdomen Svenskeya Hopen Storoya Kongseya Kviteya

maps

Topographic maps of Svalbard, published by the Norsk Polarinstitutt (NP) are published on the following scales 1:2000000 1 : 1 000 000 in single sheets; 1:500 000 in four sheets, and 1 : 100 000

Fig. 1.11. Sheet lines of maps (topographical and geological) in both 1" 100 000 series and 1:500 000 series, published by the Norsk Polarinstitutt and redrawn from sales catalogue.

SVALBARD planned for 60 sheets (Fig. 1.11). 1 : 50 000 are available as working dieline prints, with and without place names, and as official maps of various claims and 1 : 2 5 000 map of Bjornoya. There are also some local maps of settlements, mines etc. Map projections are as follows: The 1:1000000 is a conical projection, whereas all other larger scale maps are based on the transverse Mercator projection which is conveniently fitted to the rectangular grid on which the surveys have been based. The grid (essentially the same as used by the British Ordnance Survey) is defined as follows: axis of projection origin of eastings origin of northings Earth's semi-diameters

meridian 15~ 100 km west of axis 8500 km north of equator 6 3 7 8 3 8 8 m and 6356912m.

The origin is therefore false, the point 100000 having the position 15~ 76 ~ 32.89rN. The 1:500 000 map shows 100 squares, but not as above in order to conform to the international U T M series of maps.

1.8.3

Geological maps

These follow the scales, sheet lines and names of the topographic maps (see Fig. 1.11). At scales of 1: 50 000, 1 : 100 000 and 1 : 1 000 000. The principal series is published to the scale of 1 : 100 000 (Fig 1.11). It is planned for sheets to have companion outline texts. In due course these will provide a systematic description of Svalbard geology. In recent years the compilation of these maps and texts from various surveys has been the principal work of the geologists of the Norsk Polarinstitutt, often with international collaboration.

1.8.4

15 Thematic maps

These are also available (on a variety of scales), especially geomorphological. A single sheet 1:400 000 map of mineral claim rectangles is available.

1.8.5

Scientific serials of the Norsk Polarinstitutt

After a number of changes of title the principal multidisciplinary serial is Skrifter of the Norsk Polarinstitutt for monographs published irregularly. Polar Research is for shorter scientific contributions, and the Arbok which continues for internal reports etc. in Norwegian. Skrifter and Polar Research are in English. Meddelelser is of more popular or general nature and has reprinted some work published elsewhere, e.g. translated from Russian. The Polarhdndboker series of small volumes are recommended as introductory companions to this volume: No. 2 (V. Hisdal, 1985, 2nd Edn, Geography of Svalbard); No. 4 (T. B. Arlov 1994, A short History of Svalbard); and No. 7 (A. Hjelle, 1993. Geology of Svalbard), is especially well illustrated with colour photographs and maps. For further superb colour photographs and a further general account see Worsley in Aga et al. (1986), which geological history of Svalbard published by Statoil is a useful introductory supplement to this work. The Norsk Polarinstitutt (NP in this volume) has its headquarters and research facilities currently at Middelthunsgate 29, Postboks 5072, Majorstua, 0301 Oslo with an office in Longyearbyen. From 1997 the institute will move to a somewhat larger organization in Tromso.

Chapter 2 Outline history of geological research W. B R I A N H A R L A N D 2.1 2.2 2.3

2.1

Early exploration, 16 1858 to 1920, 16 1920 to 1945, 18

Early exploration

Useful records of observations perhaps began in 1596 with Barents' voyage and resulting chart. The many expeditions until the middle of the eighteenth century were primarily for whaling with minor additions to the charts. In 1758 A. R. Martin led a Swedish voyage and in 1773 C. J. Phipps commanded a British naval expedition, the first of several, to seek a northeast passage to the Pacific. They penetrated no further than Spitsbergen and made useful observations. At that time and for many years the British Admiralty was concerned with extensive Arctic exploration. The elaborate nature of these expeditions was not so much designed for scientific purposes as for useful employment for enterprising officers, with ships in numbers no longer needed in the period of naval supremacy after 1805. Hydrographic survey was often the principal achievement. In terms of efficiency and Arctic know-how the early whalers such as Scoresby were superior. 1827 may be considered as the year when geological work began, with expeditions from Norway (B. M. Keilhau 1831) and Britain (Capt. Parry, e.g. Horner 1860; Salter 1860). Keilhau, a geologist, visited Edgeoya and Bjornoya. Admiral Parry, Hydrographer of the Navy, wintered on H M S Hecla in Sorgt]orden where further specimens were collected. In 1837 an early Swedish expedition was directed by Lov+n. Then, 1838 to 1840, the French voyage of La Recherche took place under the Commission Scientifique du Nord (e.g. Robert 1840). Only a selection of the many expeditions in the second half of the century are noted here. In 1858 a Swedish scientific expedition included Nordenski61d who later led exploratory voyages with several scientific objectives, including preparatory work for the major international enterprise to determine the Arc of Meridian, as first suggested by Sir Edward Sabine. The main activity was then British, Norwegian, and Swedish, with the first German Arctic expedition in 1868. Arctic scientific exploration had become the international norm. During the years 1850 to the Treaty of S~vres (Paris) in 1920 major expeditions of various kinds include: British 33, Swedish 30, Norwegian 20, German 16, French 6, Russian 4, Austro-Hungarian 2 Dutch, Swiss and American 1 each. From a scientific point of view, distinguished work was done on many of the visits and will be referred to in later chapters.

2.2

1858 to 1920

A series of Swedish investigations led by S. L. Loven (zoologist), D. M. Torell (later Director of the Swedish Geological Survey), A. E. Nordenski61d, and later by A. G. Nathorst and G. de Geer resulted in the first systematic geological knowledge of Svalbard. Thus, whereas previous surveys were essentially for coastal charts (e.g. the British Admiralty chart of 1860), the map of Spitsbergen published in 1865, from field work done in 1861 and 1864, depicted the geological structure throughout the land area, albeit in rudimentary fashion. Nordenski61d's Sketch of the Geology of Spitsbergen (1867, 1876) integrated previous known work, and introduced the name Hecla Hoek. A detailed geological survey was accomplished during Nordenski61d's over-wintering party at Mosselbukta by C. B. Blomstrand (1864) with initial attempts to unravel Hecla Hoek stratigraphy. A further general account with a geological map

2.4 2.5 2.6

1946 to 1960, 19 1960 to 1975, 20 1975 onwards, 21

is found in Suess (1888) Das Antlitz der Erde based on information given him by Nathorst, who, after many published investigations in Arctic palaeobotany by both O. Heer and himself, wrote what was for many years the definitive account of the geology of the archipelago in 1910. Thereafter Swedish work tended to palaeontological studies, e.g. by C. J. J. E. Wiman and E. H. O. A. Stensi6. Nathorst's map (in Suess 1888 reproduced here as Fig. 2.1) distinguished eight rock groups. The Archean outcrops comprise all the more intensely metamorphosed rocks in northern 'Nord-Ost Land', western Ny Friesland and northwest Spitsbergen. The Hecla Hoek System occupies the remainder of the preDevonian outcrop area of less metamorphosed rock. The Liefde Bay System approximates the Old Red Sandstone outcrop and is separated from Archean rocks to the East by a major fault from Billefjorden to Wijdefjorden. The Ursa stage, ('Mountain Limestone', and Permian) corresponds very well to the Carboniferous-Permian outcrop. It is separated from the western outcrop of the Hecla Hoek by another major fault that parallels the coast. The Trias is roughly as now mapped. Cretaceous outcrops, which are largely continental, are not distinguished from Jurassic in this map. The Tertiary outcrops are designated Miocene which was a general opinion then for plantbearing continental sandstones and shales in the North Atlantic Arctic province. A Miocene age was the opinion of O. Heer the leading Swedish paleobotanist who wrote at that time extensively on Arctic floras, which are now mainly regarded as Paleogene. Nathorst's 1910 paper has the systematic structure of a modern monograph on the geology of Svalbard (Beitrdge zur Geologie der Bdren Insel, Spitzbergens und des KO'nig Karl-Landes). The Arc of Meridian project (1899-1902) was a RussianSwedish geodetic enterprise developed from earlier Swedish work. Preliminary investigations for this had been made by Torell in 1861 and 1864. The Swedish section was based on Sorgfjorden and the Russian section on the west coast of Edgeoya. From this remarkably ambitious project flowed many studies, and northeastern Ny Friesland and northwestern Nordaustlandet long continued as Swedish centres for scientific work. Behind much endeavour was the possibility of mineral wealth and political influence in this 'no man's land'. An abortive Swedish attempt was made to mine phosphorite at Kapp Thordsen, as well as early Swedish claims for coal. In view of their outstanding earlier work with Nathorst's palaeobotanical studies up to 1920 it caused some disappointment in Sweden that she was not awarded Spitsbergen at Versailles in the Treaty of Paris. However, at the turn of the century, when the political field was still open, the economic possibility of mineral wealth on land was in many minds. This led to a new surge of interest and, after 30 years of Swedish domination, scientific research became more international and with a competitive edge. After Nordenski61d's expeditions, few had ventured far inland. Interior geology was mostly unknown. Sir Martin Conway with geologist companions, E. J. Garwood and J. W. Gregory (1896), crossed Spitsbergen from Is0orden to Stort]orden and back in 1896. Garwood accompanied Conway the following year. This work contributed to the stratigraphy of central Spitsbergen. The Prince of Monaco arranged expeditions to northwest Spitsbergen in his yacht Princess Alice. The main work, directed by Gunnar Isachsen, was topographic and bathymetric. One object was to connect this triangulation with the Arc of Meridian Survey further east. These voyages afforded excellent geological opportunities. W. S. Bruce, a Scot, joined the vessel in 1898 and 1899 and

OUTLINE HISTORY OF GEOLOGICAL RESEARCH

17

Fig. 2.1. Geological sketch map of Spitsbergen by A. E. Nordenski61d and A. G. Nathorst, E. Suess, 1988, Der Antlitz der Erde, reproduced from E. Suess, The Face of the Earth, H. B. C. Sikes translation 1905, Oxford. Vol. 2, p. 68, Figure 8. returned again in 1906, 1907 and 1909 to explore Prins Karls Forland, which had hitherto been geologically unknown partly, no doubt, because of a lack of evident fossils in rocks. A. Hoel and O. Holtedahl accompanied Isachsen on the mainland work in northwest Spitsbergen and so began a continuing Norwegian

contribution to the Geology of Svalbard. Norwegian independence in 1905 was probably a major influence in the new strength of Norwegian geoscience. Hoel became active in promoting Norwegian interests with respect to the Spitsbergen coal potential and later was responsible

18

CHAPTER 2

for systematic geological surveys. He returned in 1911, 1912 and 1915 and discovered Cretaceous coal between Adventt]orden and Bellsund in 1916. Holtedahl, after work on Carboniferous rocks further south, used this opportunity in the northwest to contribute a first understanding both of the Caledonian nature of rocks previously regarded as Archean and of the Old Red Sandstone stratigraphy and tectonics. H. G. Backlund worked on the basic volcanics and intrusions of the area. Ki~er (1916) defined Devonian strata. Swedish work continued with Wiman's Uppsala expeditions in 1912, 1913 and 1915 to 1917. They resulted in palaeozoological publications especially on Triassic vertebrates and Late Paleozoic brachiopods. Nathorst continued his palaeobotanical studies related to coal deposits of many ages. The Swedish stratigraphical and structural studies might be seen to have culminated in 1910, not only with the publication of Nathorst's monograph, but with the Swedish led excursion of the International Geological Congress from Stockholm led by G. de Geer. The opportunity so afforded led to specialist interest by a wider international community, especially palaeontological. The international exploration for mineral wealth continued with Swedish geologists. In 1916 Birger Johnson led an expedition of 30 to investigate coal in Bellsund, in Pyramiden and in Biinsowland (both beside Billefjorden in Is0orden). Thus the Swedish coal claims were amongst the first of all the claims. Similarly the Scottish Spitsbergen Syndicate (SSS) had made coal and mineral claims. Bruce revisited Spitsbergen in 1912, 1914 to establish these. In 1919 he led a major expedition under SSS auspices and in 1920 a further SSS expedition led by Mathieson was accompanied by several geologists, including G. W. Tyrrell who published various regional studies.

2.3

1920 to 1945

The award of the archipelago to Norway under the Spitsbergen Treaty led to the establishment of the Norges Svalbard og Ishavsundersokelser under the leadership of Adolf Hoel, the forerunner of the present Norsk Polarinstitutt. It had the daunting task, for a small organization, of promoting multidisciplinary studies and organizing the hydrographic, topographic, geological and biological survey of the islands. Results from annual expeditions were published mainly in the new Skrifter om Svalbard og Ishavet. As it happened Hoel was a good organizer as well as a geologist, and the first requirement was to assess the geology of the various mineral claims and especially of the coal fields. With a stable political situation studies proceeded systematically. His own papers were published in 1924 and 1925, and with a summary of earlier Norwegian work in 1929. Norwegian activities 1936 to 1944 were reported (Anon 1945). G. Horn also wrote on the coal of Svalbard (1928), Horn and A. K. Orvin on the Geology of Bear Island (1928) and Orvin in 1934 on the Geology of the Kings Bay region a study of the Ny-Alesund coal field. Bjornoya while much nearer to Norway and generally free of sea ice is hardly more accessible because of the few landing places- none are satisfactory. However, Norwegian expeditions directed by A. Hoel established the coalfield and the general outlines of the geology of the island (e.g. Holtedahl 1920; Horn & Orvin 1928). After preliminary topographic surveys Svalbard was covered by oblique aerial photography in 1936. A major scientific initiative was to record the standard stratigraphic sequence of the Central Basin where the strata at the western limit of the outcrop, between Kapp Linn~ and Gronfjorden, dip steeply at Festningen, at the south western entrance to Isfjorden. Carboniferous to Cretaceous strata are well exposed and a series of detailed descriptions began with Hoel and Orvin's measured section in 1937. This was followed by a rapid succession of about 12 biostratigraphic descriptions of this Festungsprofil from 1928 to 1931 all mainly as Skrifter monographs and mostly by H. Frebold.

Frebold's interest led to his major synthesis published in 1935 Geologie yon Spitzbergen, der Bdireninsel, des K6nig Karl- und Franz-Joseph Landes. (Frebold's geological map is reproduced as Fig. 2.2). Oslo University-based tectonostratigraphic studies were notably advanced through the work of O. Holtedahl (1925) in which the Caledonian interpretation of Svalbard was shown to have close parallels with Scotland. As it turned out later the contemporary assumption that Caledonian Orogeny deformed Early Paleozoic rocks (by analogy with Wales) proved to be misleading in both Svalbard and Scandinavia, where the thick geological successions deformed in mid-Paleozoic time were mainly Late Proterozoic rather than Paleozoic. This misconception hardly affected the tectonic significance of Holtehal's interpretation. Holtedahl also laid the foundation of Devonian stratigraphy in Spitsbergen, of the Ordovician strata in Bjornoya and the geology of the central western Spitsbergen area. Then T. Vogt, in the course of studies of mainly Devonian strata, was the first to note the importance of Late Devonian diastrophism in what he referred to as the Svalbardian folding. Thus two main tectonic episodes were clearly distinguished in Silurian and Devonian time. Swedish work, mainly palaeontological, continued for a time. J. P. J. Ravn (1922) from marine mollusca in the Tertiary coalbearing strata established their Paleocene rather than Miocene age. A. E. Stensi6 (1918-1927) continued his detailed investigation on Devonian fish as also S/ive- S6derbergh (1935-1941) and T. Nilsson (1941-1946). T. H. Hagerman (1925) reported Swedish work in southwestern Spitsbergen in 1924. There was, however, a major expedition in connection with the International Polar Year 1931 to 1932 based in northwestern Nordaustlandet. Of the many results the work of O. Kulling on the Hecla Hoek rocks (1932-1937) provided the first systematic account of Hecla Hoek stratigraphy with description of tillites. The first tillite record had been by Garwood & Gregory (1898) in southwest Spitsbergen. British work took a different turn. From the Scottish Spitsbergen Syndicate exploration for mineral wealth grew a tradition of private expeditions organised in universities, first Oxford then Cambridge. From 1921 to 1938 12 expeditions worked in the northeast sector of Svalbard. While they were mostly multidisciplinary, there was a significant geological contribution. In 1927 on a Cambridge expedition to Edgeoya, N. L. Falcon (1928) first recorded the petroleum potential of Triassic shales. In Ny Friesland, the work of Cambridge geologists on Oxford expeditions, concerned the Hecla Hoek rocks. N. E. Odell (1927) described the unmetamorphosed succession. W. L. S. Fleming and J. M. Edmonds (1941) traversed the Ny Friesland terrane from north to south in 1933 investigating older rocks. P. E. Fairbairn (1933) and Harland (1941) worked on the metamorphic rocks following Tyrrell's (1922) petrological study. The Oxford work, mainly glaciological, then came to be centred on Nordaustlandet, but with a stratigraphic component by K. Sandford (1925-1929). As Kulling had shown that both Nordaustlandet and Ny Friesland had unmetamorphosed Hecla Hoek rocks in common, the question persisted and persists as to the relationship of these strata to the metamorphic rocks that had first suggested an Archean age in the previous century and had been so described by Tyrrell (1922). The International Polar Year in 1934 introduced Polish geologists to Svalbard and they focused their investigations on the southwest sector of Spitsbergen. The work continued in 1936 and 1938, though S. Z. Rozyicki's main work in Wedel Jarlsberg Land was not published until 1959. German expeditions (from Hamburg) visited Svalbard in 1927 (Gripp 1927-1929) and 1935. The earlier one afforded H. Frebold a further opportunity to investigate Mesozoic rocks as well as to continue with glaciological work. Soviet geological work during these years was mainly concerned with their coal concessions and little beyond. From fieldwork in 1932 Ye. M. Lyutkevich published on the Pyramiden coal field geology and D. L. Stepanov (1937) on Permian brachiopods. T. Vogt (1938) wrote on the stratigraphy and tectonics of the Old Red Sandstone deposits. In 1939 a British, Norwegian, and

OUTLINE HISTORY OF GEOLOGICAL RESEARCH

19

Fig. 2.2. Geologicalmap of Spitsbergen reproduced from Hans Frebold (1935). Geologie yon Spitzbergen, de Bdreninsel, des Konig Karl und Franz Josef Landes, 195 pp, Plate 7, in Geologie der Erde, Berlin, Gebrfider Borntraeger, Berlin.

Swedish expedition set out to investigate Devonian stratigraphy and especially to collect fossil fish (Foyn & Heintz I943). From 1939 to 1945 war in Europe brought field work in Svalbard to a close (EIbo 1952). However, the Norsk Polarinstitutt in Oslo continued to function under German occupation and this enabled a synthesizing of results to proceed under Hoel's direction, Notable achievements were A. K. Orvin's (1940) Outline of the Geology and History of Spitsbergen and his monumental Place names of Svalbard (1942, Skrifter No. 80). Similarly H. Frebold continued to work in occupied Denmark and part of his work developed into his Geologie des Barentsschelfes (1951). Geologically irrelevant but of prophetic interest were the polar flights based on Spitsbergen during 1924-25 when Amundson and Ellsworth made a flying boat attempt, and in 1926 they with Nobile flew from Spitsbergen to Alaska in the dirigible Norge. In the same

year Byrd flew to the Pole; and in 1928 Wilkins flew from Alaska to Spitsbergen, the year that the ill-fated Nobile attempt by airship Italia crashed with the loss of some personnel and of Amundson on his rescue attempt. In 1938 Lauge Koch reconnoitred Greenland, from Spitsbergen, for air support for his post-war East Greenland expeditions.

2.4

1946 to 1960

The post war reconstruction of the mines destroyed in the war was a first priority along with the re-establishing of navigation beacons. The Norsk Polarinstitutt (NP) was refounded in 1948 in Olso in succession to the Norges Svalbard - og Ishavs-Undersokelser. One

20

CHAPTER 2

of the last Skrifter (No. 89) to be published under that name from war time compilations was Orvin's Bibliography of literature about

the geology, physical geography, useful minerals, and mining of Svalbard (1947). The organization of the institute and its publications continued with little change except of name and the inclusion in its remit of Antarctic research and with some expansion of staff. Harold Sverdrup (oceanographer) replaced Adolf Hoel as Director in 1940 until his death in 1951 when Anders Orvin, who had been the senior staff and principal geologist, followed as Acting Director until his retirement in 1960. In 1948 the Norsk Polarinstitutt began annual field work in Svalbard for systematic hydrographic, topographic, geodesic and geological surveys, as well as research in other disciplines. Since 1948 the Norsk Polarinstitutt has been the leading Svalbard research institution for geology, as well as for many other disciplines. Early postwar research, focused at first on Sorkapp Land where, in the enigmatic 'Hecla Hoek' rocks, Cambrian and Ordovician fossiliferous successions were reported by H. Major and T. Winsnes (1955). Operational research on the Tertiary coalfields was continued by Major, with palynological investigations by Manum (1954 and 1960). A dictionary of all named and published stratal units of Svalbard was prepared by Major et al. (1956) as part of the French inspired International Stratigraphic Lexicon. Paleontological studies continued in the University Museum, Oslo (e.g. Wangso 1952). In 1956 in connection with the third International Geophysical Year, Polish work under the leadership of S. Siedlecki resumed in Wedel Jarlsberg Land between Bellsund and Hornsund from a new base (Ibjornhamna) on the north shore of Hornsund. While the earlier work was published, new work led by Birkenmajer and his team described the complete stratigraphy along the north of Hornsund (1958-1959). This usefully complemented the work by the Norsk Polarinstitutt in Sorkapp Land just south of Hornsund. The new features of this work; in addition to confirming fossiliferous Cambrian and Ordovician strata (e.g. Kielan 1960) was to formulate a long sequence of Precambrian strata and tectonic events supported by petrological studies with suggestions of granitization (Narebski 1960, Smulikowski 1960). Almost continuous multidisciplinary Polish work since then is recorded in the works of Birkenmajer and his colleagues. The combined results of the Norwegian and Polish work were presented to the members of the excursion of the 1960 International Geological Congress. During this excursion footprints of Cretaceous Iguanodon were demonstrated (e.g. de Lapparant 1962). In the meantime private ventures from a number of British universities had been active and indeed resulted in the larger number of geological publications during these 15 years. Birmingham groups in 1948, 1951, 1954 and 1958 worked in southern Oscar II Land between Isfjorden and St Jonsfjorden where slices of Carboniferous and Permian strata with distinctive fossils are tightly compressed with Precambrian strata (Baker Forbes & Holland 1952). In addition to structural studies (Weiss 1953, 1955, 1958) Carboniferous and Permian strata were described (Dineley 1958). The problem of distinguishing deformation structures that are preCarboniferous from post-Permian became evident and persists. Devonian rocks with fish in Ekmansfjorden were also introduced (e.g. Dineley 1955, 1960; Barr 1960). Atkinson of Imperial College, London worked in Prins Karls Forland in 1950, 1951, 1953 and mapped the area in more detail than previously (1952-1963). Oxford work was largely glaciological and Sandford continued to publish results from earlier field work, and new aerial photographs (1950-1963). From the Queen's University, Belfast, work between Isfjorden and Kongsfjorden further elucidated understanding of the Precambrian strata (Bates & Schwarzacher 1958; Preston 1959). From Durham University a party investigated inner Kongsfjorden, and A. Challinor, one of its members, later joined the Cambridge group. This Cambridge group (CSE) led by W. B. Harland first arranged a small party in 1948 to investigate the Scottish Spitsbergen Syndicate properties in Btinsow Land. This was followed in 1949 by Carboniferous and Permian studies (Gee, Harland & McWhae

1953; Forbes 1960; Forbes, Harland & Hughes 1958). The structural problem of the Billefjorden Fault Zone was addressed by McWhae (1953). It then seemed to be initially a compressive thrust fault system. Most effort was devoted to the survey, topographical as well as geological, of Ny Friesland to determine the Hecla Hoek succession and its relation to the schists and gneisses occupying the western part of the Land. This was an old problem. It seemed to be solved by extensive reconnaissance mapping which showed a relatively concordant sequence of about 18km of strata in which the metamorphic rocks comprised the lower part. No major unconformity had then been demonstrated (Harland & Wilson 1956) and the Caledonian deformation and deep burial seemed to account for the tectonic contrasts (Harland 1959). The succession was first divided into Lower, Middle and Upper Hecla Hoek; the Lower being metamorphosed (Bayly 1957), the Middle only partly so (Wilson 1958 and posthumously 1961), and the Upper part in two groups a lower tillite-bearing group (Wilson & Harland 1964) and overlying Cambrian and Ordovician strata - the first fossils, Salterella rugosa, being found by Wilson in 1955 and then a richer Ordovician fauna (Gobbett 1960; Gobbett & Wilson 1960; Hallam 1958). Investigations of this rich succession had only just begun by 1960 and it already had become, perhaps prematurely, a standard for comparison and correlation of Precambrian rocks elsewhere in Svalbard (e.g. Harland 1960). In 1958 palaeomagnetic collections throughout the unmetamorphosed rocks of the area were made by D. E. T. Bidgood for comparison with Greenland (Bidgood & Harland 1961) but the samples proved to be unstable. Beginning in 1951 and 1953 the structures in the Old Red Sandstone, west of Wijdefjorden, had been noticed overlying the Billefjorden Fault Zone (as later named) and P. F. Friend began his investigations of the Old Red Sandstone rocks in 1955 and continued in 1958 and 1959. His main work and the published results followed from 1960 onwards (e.g. Friend 1961; Friend & Moody-Stuart 1972). At this time although Soviet Geologists were not active far outside the coal concessions their prominence in continental and global map compilations in Moscow inevitably led to the need to include Svalbard and so interpret its structure. An example is Klitin's (1960) paper on the tectonics of Spitsbergen with its prevailing fixist interpretation and a network of deep-seated faults dividing the terranes.

2.5

1960 to 1975

A major change in Svalbard research came about with the industrial interest in the petroleum potential in the Barents Shelf. In 1960 the Shell Oil Company addressed the possibilities and AMOSEAS (a consortium of Chevron and Texaco in the US) undertook their own systematic investigations. A new era of logistic support, previously unthinkable, with helicopters and skidoos was introduced replacing to a large extent dependence on small boats, man-hauled sledges and pack-carrying. Larger vessels continued to be essential for logistic back-up. These changes coincided with the general acceptance of standardised international conventions, especially in stratigraphic nomenclature. Previously, as with place names different groups had developed their own mainly European practices and the recently developed North American Stratigraphic Code which, for rock unit nomenclature formed the basis of the international standard, had the effect of focusing stratigraphic work on the whole rock unit rather than on the interesting beds or fossiliferous niveaux. Probably another consequence of this American petroleum influence was the decision in the USSR to match this new scientific input. From then on each year Soviet geological parties each of three or four, with heavy camps suited to the Soviet Arctic, were deposited by large helicopters according to a systematic programme throughout Svalbard. The Soviet tendency was to work

OUTLINE HISTORY OF GEOLOGICAL RESEARCH independently and produce their own confidential maps of the whole region. Many results were published, but at first detailed maps and other records were not available as was also the case with the western petroleum companies. Sokolov (1965) and Krasil'shchikov (1973) synthesized results of the older rocks. Until about 1960 practically all geological work had been of a reconnaissance nature and the different areas of interest that tended to be the province of one research group were not trespassed upon by other groups. This had the effect that any geological synthesis tended to be a compilation of different components each generated by a differing outlook. From about 1960 onwards territorial preserves ceased and there was enough geological personnel for the main groups each to extend elsewhere in whole region. This certainly applied in different ways to oil company exploration, the Norsk Polarinstitutt, the Soviet presence mainly organized through the Institute for the Geology of the Arctic in Leningrad, the Polish work mainly in the south and, with less resource, to the Cambridge group which graduated from small open boats and man-hauled sledges to enclosed motorboats. The Norsk Polarinstitutt had in 1960 a new Director, Tore Gjelsvik. His emphasis was first to ascertain whether any mineral resources had been overlooked. Geological publications during this 1960-1975 period were at a rate more than three times that of the preceding 15 years. Increased output tends to submerge significant scientific developments. Groups centred in Oslo, Leningrad and Cambridge were each comprehensive in their interests and similar in output. The Polish group on the other hand focused on the southern part of Spitsbergen. This had the advantage of more thorough connected studies but lost in some appreciation of their regional context. By 1975 all areas of Svalbard had been described in some degree, some areas by more than one group. Stratigraphically rock units had been named consistently with more or less standard descriptions of the strata, based on innumerable measured sections and so with a systematic view as to their local variation. Individual palaeontologists, especially in France and Germany as well as in the other groups, described more and more fossils from the rich horizons. Devonian fish were investigated especially in Oslo and Paris. A new Ordovician fauna was discovered in northeast Ny Friesland first by Cambridge and later investigated by the Natural History Museum in London and the University Museum in Oslo. The ubiquitous coal and plant bearing strata were the subject of palaeobotanical studies which were largely done in Germany whereas palaeontological investigations were active in Cambridge, Oslo, and St Petersburg. Mesozoic ammonites were described in detail in Hamburg, St Petersburg, and in England. CarboniferousPermian faunas were described especially in Poland, Britain and Soviet Union. Moscow palaeontologists made comparisons of stromatolites, oncolites and phytolites with Late Riphean sequences in the Soviet Arctic. Mineral occurrences and geochemical studies were especially undertaken in the Norsk Polarinstitutt, but are of genetic rather than economic interest. Petroleum prospects were explored with deep wells in Spitsbergen, Edgeoya and Hopen (Appendix). Perhaps the result of these 15 years work was to remove the early optimism about the land areas of Svalbard as good petroleum prospects. Source rocks occur; but tectonic compaction and sedimentary facies and erosion have reduced the likely petroleum content of the reservoirs. Since then the main interest of Svalbard to the petroleum industry has been as a sample of the strata already being delineated by seismic and other surveys in the Barents Sea. Coal, petroleum and mineral exploration are discussed further in the appendix. The better understanding of the local geology provided a platform for informed tectonic studies. These 15 years corresponded with the conversion of a majority of geologists to accept hypotheses of continental drift with the early development of plate tectonic interpretations. In such studies Svalbard played a key role from the very beginning. The detailed separation of Spitsbergen from north of Greenland with the complex opening of the Norwegian Greenland ocean basin, and the (simple) spreading

21

about the Nansen-Gakkel Ridge to form the Arctic Ocean Basin were amongst the first kinematic results to be established. They had indeed been anticipated by Wegener (1924), Taylor (1928), du Toit (1937) and by Carey (1958). Svalbard data yielded one of the first instances where palaeocontinental drift was argued with the closing of the Iapetus Ocean that separated Greenland with Svalbard from Norway and the Baltic Shield. Major Devonian sinistral strike-slip had already been suggested (Harland 1965) to move Svalbard from central East Greenland to the south of north Greenland and by 1971 sinistral transpression (and transtension) along the Billefjorden Fault Zone had been identified. The long history of this fundamental fault was documented in 1974. By 1975 it was suggested, not only on the basis of structures, but mainly on that of contrasting stratigraphic sequences in distinct terranes, that Svalbard now comprised at least three major allochthonous terranes with subterranes, separated by at least two fundamental strike-slip fault zones. The allochthonous terrane concept elsewhere in the world became generally accepted and was gradually applied by more scientists in Svalbard (see section 3.5). Svalbard was also noteworthy because of the ubiquitous diamictites, which contribute excellent evidence for the global Varanger (late Vendian) ice age, for long doubted but now generally accepted. The two distinct Varanger tillite horizons are recognizable in all three Svalbard provinces or terranes, thus giving a basis for wider correlation. Subsidence of the Hecla Hoek geosynclinal basin by thermal contraction of the mantle was also one of the early suggestions of a mechanism (Harland 1969) that has since become rigorously established but in this case on a far longer time scale. Whereas the deformation of strata up to early Paleocene in age along the western margin of the Central Basin had long been established (e.g. Orvin 1934, 1940) new reconnaissance demonstrated a far more elaborate fold and thrust belt than had earlier been anticipated. This investigation of the structure of PostDevonian strata was led by A. Challinor (e.g. 1967 and Fig. 20.8). The West Spitsbergen Orogen was so defined (Harland & Horsfield 1974). The immense interest of these structures has subsequently resulted in a flood of publications (e.g. Dallmann et al. 1993a). During the late 1960s and early 1970s the availability of helicopter platforms on ice-strengthened ships enabled renewed reconnaissance of the eastern islands of Svalbard by Norwegian and Cambridge parties (see especially Chapter 5).

2.6

1975 onwards

The all-weather Longyear Airport was opened in 1975 and thereafter contributed to the increasing scientific activity, not least by enabling field work to increase at the expense of travel time. The rate of publication of serious geoscientific work relevant to Svalbard continued to increase to more than 50 significant geoscientific publications a year. A notable change was the participation of many American and then Japanese scientists so that Svalbard ceased to be so conspicuously a European scientific arena. Whereas hitherto much of the stratigraphic endeavour had been unsophisticated, a new onslaught with sedimentological expertise and palaeogeological interpretations now becomes the rule. Similarly a more rigorous discipline in structural geology was applied so that far more information was obtainable from a local study than previously. Thus the intensive structural studies within and beyond the West Spitsbergen Orogen mushroomed with investigations dominated by Norwegian and American geologists as summarized by Dallmann, Andresen et al. (1993). New palaeontological techniques were brought to bear so that, for example, the immense mass of Hecla Hoek rock of the Ny Friesland geosyncline, hitherto thought to be mostly barren, yielded fabulous detail of microbial remains preserved in chert going back hundreds of millions of years into Precambrian time (e.g. Knoll 1982, 1985).

22

CHAPTER 2

Submarine and aerial surveys by industry were becoming available. Seafloor spreading sequences for the Norwegian Greenland seas in particular for Cenozoic configurations were worked out in detail with adequate control especially in the University of Bergen with its strong geophysical divisions. Microseismic cooperation between American and Norwegian seismologists began to map out the contemporary stress-strain adjustments in Svalbard with perhaps unexpected results (e.g. Mitchell et al. 1990). A local matter, but significant from the author's point of view, was that while hitherto the Cambridge group had enjoyed active cooperation for Svalbard research with the petroleum industry in Norway, it became understandable Government policy to recommend companies seeking concessions to commission work from Norwegian institutions and this acted positively to encourage the Cambridge group to extend their comparisons with the Soviet, Canadian Arctic and Greenland (the author having worked a little with Lauge Koch). So in 1975 the Cambridge Arctic Shelf Programme (CASP) was formed and Cambridge Svalbard Exploration (CSE) was slowly merged with it. The scientific consequence was to focus on the whole Arctic in which Svalbard would always be a key element. From being a personal charitable enterprise, CASP became a company limited by guarantee with charitable

status in 1988. As such, its prime object continues namely research, publication and education. The Norsk Polarinstitutt under its new government umbrella, the Ministry of the Environment, led by the Chief Geologist, W. K. Dallman pursued a vigorous policy, giving priority to the systematic completion of the 1 : 100 000 geological map series, each with an accompanying explanatory text. In this programme foreign geologists were invited to participate both in comment and criticism and as joint authors. For many years the Norsk Polarinstitutt had arranged logistic support for groups engaged in local mapping projects, but the new policy gave the international community an opportunity to engage in cooperative research. It had long been policy that mapping, both topographic and geological, should be organized by the Norsk Polarinstitutt. This volume may be seen to mark the fulfilment of the reconnaissance phase of Svalbard geology as recounted above. The future is exploding with detailed and systematic investigation of the archipelago according to new and more rigorous standards and certainly with participation of scientists from many countries increasingly coordinated by and cooperating with the Norsk Polarinstitutt. One example is the publication in English of Russian work, some previously unpublished (e.g. Krasil'shchikov 1996).

Chapter 3 Svalbard's geological frame W. B R I A N 3.1 3.1.1 3.1.2 3.1.3 3.1.4 3.1.5 3.2 3.2.1 3.2.2 3.2.3 3.3

The space frame: Svalbard's structural frame, 23 Solid outcrops, 23 Regional descriptive sectors, 23 Discontinuities as convenient boundaries, 23 Structure of Svalbard, 25 Kinematic interpretation of Svalbard's history, 25 The time frame, 25 International time frames, 25 A provisional time scale, 28 Svalbard's chronometric record, 29 The rock frame, 29

This chapter gives an outline of the geology of Svalbard, an introduction to the principles applied in this work and a preview of the interpretations and conclusions that have come out of these studies. The key position of Svalbard in relation to other Arctic lands is shown in a Polar projection (Fig. 3.1).

3.1 3.1.1

T h e s p a c e frame: S v a l b a r d ' s structural f l a m e Solid outcrops

The conventional geological map of Svalbard shows in outline the outcrop areas according to age. (Fig. 3.2). Although rock ages are matters of interpretation, the diagrammatic map is at least consistent with the conclusions in this work. It differs from most maps in the larger outcrop of Vendian rocks within the basement. The outcrop pattern ignores Quaternary deposits, i.e. it is a solid geology map. It is diagrammatic because detail is impossible to show on this scale. The larger ice masses which obscure the exposure are also diagrammatic.

Fig. 3.1. Svalbard in the Arctic (polar projection), based on various sources. Greenland has been officially divided as indicated by the dashed boundaries and initials, EI is Ellesmere Island; NS is Nares Strait.

HARLAND 3.3.1 3.3.2 3.4 3.4.1 3.4.2 3.4.3 3.5 3.5.1 3.5.2 3.5.3 3.5.4

3.1.2

A lithic code, 29 Some practical stratigraphic conventions in this work, 31 Teetonostratigraphie terranes and their sequences, 31 The terranes and their sequences, 32 Combined sequence for Svalbard, 36 Sequence stratigraphy, 37 Geotectonic interpretations, 37 Provinces and allochthonous terranes, 37 Differential horizontal lithosphere motions, 38 Polar and lithosphere wander, palaeoclimates, 40 Differential vertical lithosphere motions, 43

Regional descriptive sectors

Because the intention in this work is generally to describe rocks before interpreting their history and so not to begin with too many assumptions, the rocks are described in Part 2 of this work in the eight sectors or regions (Chapters 4 to 11) as shown in Fig. 3.3. Their boundaries are not fixed because it is convenient to treat some geological matters together in one chapter, even when they might overlap onto another. They are not terranes. Where strata are described the succession is presented as observed with the youngest at the top (as in Part 2). When the sequence is interpreted later (as in Part 3) the earliest events precede the later.

3.1.3

D i s c o n t i n u i t i e s as c o n v e n i e n t b o u n d a r i e s

Some boundaries on the geological outcrop map are important discontinuities. These are mainly fault zones or lineaments and some are fundamental in the sense that they dip steeply and persist through long spans of geological time. Other boundaries are perhaps equally significant as unconformities which, generally dipping gently, do not appear as fixed lineaments on a map.

24

CHAPTER 3

SVALBARD'S GEOLOGICAL FRAME Figure 3.4 depicts important named fault zones or lineaments as continuous lines. Dashed lines indicate the major unconformity between the older (pre-Carboniferous rocks) and the younger postDevonian strata. The fault abbreviations listed in the caption to the figure may be used throughout this work. These boundaries separate descriptive terranes or subterranes as listed in Section 3.4.4 with their distinct tectono-stratigraphic sequences.

3.1.4

25

/

I/

/

1/2 ~

I

16 ~

/

2 0 c"

28 ~

24 ~

Structure of Svalbard

32 ~

/

I

.%

l

Figure 3.5 shows Svalbard in relation to the structural elements of the Barents shelf and especially the position of Bjornoya in that context. Figure 3.6 shows diagrammatically the structure of the rest of Svalbard according to the interpretation of Russian geologists (Krasil'shchikov, Abakumov et al. 1996). It is a useful summary of one viewpoint which assumes that the structural elements of Svalbard as seen now have persisted in that relationship through geological time. It is therefore a basis from which kinematic interpretations of Svalbard's history that led to the present configuration may be explored.

5

~

3.1.5

!i

Kinematic interpretation of Svalbard's history

Postulated successive spatial arrangements in a palinspastic sequence depend on interpretation of similarities and contrasts between terranes, not only in Svalbard. These may be speculative or controversial postulates and are reserved for Section 3.5 in this chapter. However, it is one of the objectives in Earth history to elucidate past movements between lithospheric plates. The description of Svalbard tectono-stratigraphic sequences is therefore arranged here in the terranes selected for convenience in discussing palinspastic possibilities without prejudice as to their prior configuration. Should Svalbard, as concluded later, be the result of juxtaposition of far-travelled terranes deriving from distinct provinces the exercise may be worthwhile even if it be contradicted by new evidence. But this discussion is for Section 3.5 and is touched on especially in Chapters 12-15 in Part 2.

KEY

"i

I

11

0 I

krn I

I O0 I

Fig. 3.3. Regions of Svalbard as used in this book for Chapters 4-11, with the general extent of coverage for particular chapters in Part 2. The numbers refer to the numbered chapters as follows: (4) Central Basin; (5) Eastern Platform; (6) Northern Nordaustlandet; (7) Northeastern Spitsbergen; (8) North central and northwestern Spitsbergen; (9) Central western Svalbard; (10) Southwestern Spitsbergen; (11) Bjornoya and related submarine shelf.

Neogene plateau lavas

Silurian-Devonian plutons

Paleogene

Cambrian-Ordovician

3.2

Early Cretaceousbasites

Vendian

3.2.1

EarlyCretaceous

Late Neoproterozoic

There are two elements in the standardization of international geological time: chronostratic and chronometric (Harland et al. 1990).

Jurassic-Cretaceous dolerites

Early Neoproterozoic granites

~

Jurassic

~

Triassic

Early Neoproterozoic volcanics ?Early Neoproterozoic granites and migmatites

Carboniferous-Permian /

Late Paleoproterozoic basement

~

[~

Devonian Fig. 3.2. Generalized geological map of Svalbard, from various sources and this work.

The time frame International time frames

Chronostratic scale. This scale, commonly referred to as the stratigraphic scale, began nearly 200 years ago as a sequence of geological events, even catastrophes, which divided Earth history into natural chapters. These packages of strata, developed step by step, into the geological systems with their series and stages. When it was assumed that there was a definite identifiable body of rock constituting a system it was logical to divide it into upper, middle and lower etc. It was inherent in this thinking that rocks existing today (i.e. in Holocene time) could be interpreted by superposition processes as formed in successive earlier times. 100 years later it became evident that the stratal record did not divide globally in an easily identifiable way and the problem became

26

CHAPTER 3

Fig. 3.4. Principal discontinuities in Svalbard. Fault lineaments: (BBF) Breibogen Fault Zone: (BFZ) Billejorden Fault Zone; (HBF) Hannabreen Fault; (KHFZ) Kongsfjorden-Hansbreen postulated fault zone; (KVL) Knipovich Lineament; (LFZ) Lomfjorden Fault Zone; (RFF) Raudfjorden Fault Zone; (VL) Veteranen Line; (WSTF) West Spitsbergen (orogenic) Thrust Front. Major unconfomities with relevant age indicated by dashed lines and a dotted line.

one of the correlation of essentially diachronous boundaries. Then after another 50 years it was realized that for international agreement to use the same boundaries it was necessary to standardise each b o u n d a r y at only one point (the GSSP = Global Stratotype Section and Point) or 'golden spike' (Cowie 1986; Cowie et al. 1986; R e m a n e et al. 1997). Moreover, this point was to be defined geometrically in strata and was to be interpreted as a point in time (e.g. the m o m e n t of deposition o f that sand grain). Elsewhere any rock age should be expressed as earlier or later than this point event. The age o f rock elsewhere is thus never certain, but rather for estimation and judgment. This changes with changing technology. As far as possible the traditional stratigraphic divisional names were applied and are being standardized in this way. Perhaps one consequence of this procedure, not yet c o m m o n l y applied, is that ages o f most rocks are estimated by time correlation from the standard and the time scale is expressed as time, i.e. early and l a t e - no longer lower and upper. The practice was applied (e.g. t h r o u g h o u t in H a r l a n d et al. 1990) without dissent and should be applied t h r o u g h o u t this work. The concept o f a geological system as a chronostratic division is operationally o u t m o d e d . It exists, but its exact boundaries c a n n o t be k n o w n and therefore c a n n o t be a standard. The international c o m m u n i t y is working towards the standardization of such a chronostratic scale and its current state is

Fig. 3.5. Major structural features of the western Barents Shelf, based on fig. 3.1 of Vorren et al. (1991), Marote Petroleum Geology, 8.

tabulated broadly in Fig. 3.7. The details, where relevant, will be discussed period by period in Chapters 12-21 in Part 3. We observe rocks that can properly be divided as needed into lithic units: lower, middle and upper. The code for their use, as far as this work is concerned, is outlined in Section 3.3. below.

The chronometric scale. This, c o m m o n l y referred to as t h e numerical scale, is the generally used scale in years. It is far from absolute in its application to rock. Only two elements are required for international agreement (i) the standard for the unit of time and (ii) any classification of spans of such units and their names. (i) A year no longer depends on the standard year of the International Astronomical Union, but on its calibration in seconds as defined by the International Union of Weights and Measures in terms of perturbations of the cesium atom. These refinements are irrelevant for geological estimates of age. All ages may be expressed numerically, commonly for pre-Pleistocene stratigraphy in millions of years. The convention in this work is that Ma stands for an age, i.e. so many million years before the present. (ii) However, the second requirement is optional, i.e. to name specified intervals of time defined, not by GSSP but by an exact number of years. For the rock record in Precambrian time this has been agreed by the International Union of Geological Sciences. These names are appended here. There are numerous technical reasons why numerical estimates of age can hardly be true ages but rather apparent ages, which is only one reason for not regarding them as absolute. Even the errors properly quoted merely measure the limitation of the laboratory results and ignore the many other uncertainties arising from the geological history and relationships of the sample. The

SVALBARD'S GEOLOGICAL FRAME )MM & LM.t

27 !

!

12 ~

\ 30 ~

21 ~

_80 ~

ilia+

+ + +1|

++++++ +++++ ++++++

+++++) NORDAUSTLANDET

~79 ~

79 ~ ~O~ G ~

~

78 ~-

-78 ~ SPITSBERGEN

EDGEC)YA Folded b a s e m e n t

~

Devonian molasse

complex

~

Platform cover Major f a u l t zones

-77 ~ ~IU.

77 ~-

~ A x e s of a n t i c l i n e s (a) and s y n i c l i n e s (b)

Hopen

I North-East uplift II Nordenski6ldbukta anticlinorium:

1 PrinsOscars Land horst-anticline 2 Lovdn syncline 3 Nordkapp anticline III Hinlopenstretet synclinorium Ilia Eastern limb IIIb Western limb

Fig. 3.6. Major structural elements of Svalbard, a Russian interpretation. Redrawn with permission from Krasi'shchikov et al. (1966). Main features of the Geology of Svalbard in Krasil'shchikov (ed.) Soviet geological research in Svalbard 1962-1992, extended abstracts of unpublished reports, Meddelelser, 139, Norsk Polarinstitutt, Oslo, pp. 14-15.

4 Floraberget anticline 5 L~goya synciine 6 Kinnvika syncline 7 Sveanor syncline 8 Sparreneset syncline 9 Heclahuken anticline 10 Kluftdalen syncline 11 Gulfaksbreen anticline 12 Veteranen syncline 13 Kvitbreen syncline IV Wester Ny Friesland anticlinorium:

14 Atomfjella anticline 15 Bangenhuken anticline V North-West uplift:

16 Richardvatnet anticline 17 Sn~fjella syncline

following scale though endorsed by the IUGS, confuses latinized event names with precise numerical definitions and may gradually be superceded by the chronostratic scale as it extends backwards into Precambrian history except for the names and divisions in bold letters and numbers. Other ages are given by number.

I

!

I

Major basement structures:

30 ~

21 ~

12 ~

18 Krossfjorden anticline 19 Blomstrandhalvoya graben-syncline 20 Mitrahalvoya syncline Vl West coast horst-anticlinoriun: 21-26 minor synclines:

21 Bulltinden 22 Alkhomet 23 Kapp Lyell 24 Sofiekammen 25 Luciakammen 26 Hornsundtind

Major structures of Devonian complex and platform cover: vii Devonian graben of Andrde Land:

27 Inner horst 28 Andree Land anticline VIII West coast horst-like uplift: 29-33 superimposed graben-troughs:

29 Kongsfjorden 30 Forlandsundet 31 Renardodden 32 Hornsundneset 33 Oyrlandet 34 Olsokbreen swell

IX West-Spitsbergen graben-like trough:

35 Iradalen depression 36 Holmsenfjellet swell 37 Skiferdalen depression 38 Reindalen swell 39 Tverrdalen depression 40 Bettybukta depression 41 Isbukta swell X Sassendalen monocline XI East-Svalbard horst-like uplift:

42 East-Spitsbergen depression 43 Barentsoya-Edgeeya swell

Major fault zones: 1-4 fault zones:

1 Western marginal zone 2 Eastern marginal zone 3 Pretender zone 4 Erdmannflya-Bohemanflya zone 5-9 faults:

5 Raudfjorden-Kronebreen 6 Bockfjorden-Ekmanfjorden 7 Lomfjorden-Agardhbukta 8 Hinlopenstretet 9 Duve~orden

Precambrian Chronometric Scale as defined internationally (Table 3.1). P h a n e r o z o i c is n o t classified chronometrically. The initial C a m b r i a n b o u n d a r y is defined in G S S P in N e w f o u n d l a n d , therefore the age (here at 545 Ma) is a current estimate a n d n o t a definition (Tucker & M c K e r r o w 1995).

28

CHAPTER 3

Table 3.1. Precambrian chronometric scale Neo-Proterozoic III

Eon

Neoproterozoic

Pedod

Era

650 Ma

O

Cryogenian

N 0 r-

Tonian 1000 Ma

(J

Epoch

Quatemary

Q

Neogene

Ng

Paleogene

Pg

Stenian K2

Ectasian Cretaceous

1400 Ma

K1

Calymmian 1600 Ma Statherian

J3

1800 Ma o

2050 Ma

N 0 O0 (I)

Rhyacian 2300 Ma

Jurassic

J2

2800 Ma Tr 3

Mesoarchean

3.2.2

Triassic

3200 Ma

O

3600 Ma

O N O n,' uJ Z < "T" EL

A provisional time scale

The above international conventions simply inform us how to use names and numbers. However, the calibration of the chronometric by the chronostratic is always a scientific problem that is never finally soluble. A time scale is thus one of many attempted calibrations (in years) of the chronostratic scale. Ages of events are often quoted in years without calibration as though the calibration is an established fact. With so many time scales in use it was decided to make a single justified scale so that Svalbard history could be discussed within one group (CASP) at least on a common basis. This was first completed in 1982 and a more thorough revision attempted in 1989 (Harland et al. 1990). The attempt was made to apply the latest or most likely international, rather than regional, nomenclature and classification. The Cambrian and consequently parts of the Ordovician scale were especially weak at that time owing to lack of good determinations. A new crop of U - P b zircon ages has since greatly strengthened this part of the scale as reviewed by Tucker & McKerrow (1995). The accompanying Fig. 3.7 combines the two scales referred to above so that the later values replace the earlier ones wheresoever they can be applied throughout Cambrian, Ordovician and Silurian time. Otherwise the scale is as published in 1990. In making this composite scale without the many other improvements an important principle is at stake: a published calibration is of little use if the reasoning behind it is not clear. In this case the data and arguments are available in Harland et al. (1990) and in Tucker & McKerrow (1995). It is the intention that this scale be used throughout this work for comparison and consistency; but not with any suggestion that it is correct or even the best. In any case these new data from Newfoundland and Britain are reasonably consistent with somewhat earlier determinations from Russia (Bowring et al. 1993; Knoll et al. 1995)9 Figure 3.7 is simplified for use in Svalbard where asterisks mark ages which have some biostratigraphic basis. Rocks thought to be more than 1000Ma old have not yet yielded fossils and age estimates depend entirely on isotopic determinations. Figure 3.8 tabulates some of these critical data. Improvements will continue indefinitely. One chronostratic change referred to in Chapter 14 is that the Llandeilo division may well be subsumed as Llanvirn

8.5 32 15

"k

13 7 14

132 146

Kimmeridgian W Oxfordian -k

11 157

"k W

Bajocian

21 178

30

Hettangian

4000Ma

12.0 21.0

97 "k * -k

Tr 2 Tr 1

Permian

P1

=~ Pannsylvanian C 2 s -2 Mississippian

C1 D3

o

N 0

D2 Devonian

(0 EL

D1

Silurian

Ordovician

Rhaetian

W

Norian Camian Ladinian

-k -k ~k

Anisian Scythian Lopingian

W -k ?9

27 235 241 245

13 9 5 8 8 12 10 17 13

Pragian Lochkovian

25

03

Ashgill Caradoc

02

(Llandeilo) Llanvim

"k -k

Merioneth

"C2

St David's Toyonian Botomian

Sinian

Sturtian Karatau Riphean

2 11

428 443

15 6 9

458 ~t

6 6

47O 495

15 ~

10

~,

23 518 "k

Atdabanian Tommotian Nemakit Daldyn k9 Ediacaran

4 3

525

L 534

,

9

545 21 590

Varangian

o* [ -610 -800

, ^

I 1050

Yurmatin Burzyan

[ ~

i

Neoproterozoic

10 190 --

1000 Mesoptz

1650 2200

~

2450

~

2800

-?- - -

,

1350

Animikean Huronian Randian Swazian Isuan

14

?--k--

Arenig

-C~

14

417

Tremadoc

Vendian

5

.k I "k 290 "k .k 303 Moscovian -k Bashkidan -k 323 Serpukhovian "k Visean "k Tournaisian -k 363 Famennian -k Frasnian "k 377 Givetian Eifelian ~, 391 Emsian -k

Wenlock Llandovery

s

6 4

Sakmadan Asselian Gzelian Kasimovian

S2 S1

Cambrian

1 t

6 13

Pridoli Ludlow

O1

2O8

Guadelupian -k , Kungurian W L! 256

S4 S3

Ma

3.5 18.3

J1 i Sinemurian

2500 Ma Neoarchean

Paleoarchean

0.01 1.63

35.5 t 56.5 65

Aalenian Toarcian -k Pliensbachian

Siderian

Eoarchean ...?...

Aptian Barremian Neocomian "rithonian

-Myr

23.5

Oligocene Eocene Gulf Albian

-Ma 0.01 1.64 5.2

Pliocene Miocene

Callovian Bathonian

(J

Orosirian Paleoproterozoie

Ct

Paleocene

1200 Ma Mesoproterozoie

Holocene Pleistocene

o

850Ma

Chronometric standard

Estimated calibration

Chronostratic standard

545 Ma

1600 Paleoptz 2500

Archean

3500 oonn

Fig. 3.7. Provisional time scale used in this book, the asterisks mark Svalbard strata with fossil record. Compiled from Harland, Armstrong, Cox, Craig, A. G. & D. G. Smith (1990) and modified from Tucker & McKerrow (1995) for Cambrian through Devonian numerical values.

SVALBARD'S GEOLOGICAL F R A M E ( F o r t e y e t al. 1995, b u t c o u n t e r e d by Basset & O w e n s 1996). A n o t h e r p r o b l e m is the status o f the latest P e r m i a n L o p i n g i a n division ( C h a p t e r s 17 a n d 18). N e w scales a p p e a r frequently, b u t are n o t i n t e g r a t e d into this w o r k (Shell 1995; G r a d s t e i n & O g g 1996).

3.2.3

Svalbard's chronometric record

A p p a r e n t n u m e r i c a l ages f r o m isotopic d e t e r m i n a t i o n s o f S v a l b a r d rocks are i n d i c a t e d against a c h r o n o m e t r i c scale (Fig. 3.8). Particular d e t e r m i n a t i o n s will be discussed in their historical c o n t e x t in P a r t 3 w h e r e they are critical (with their sources referenced). This p l o t s h o w s the range o f m o s t p u b l i s h e d results. Analytical a n d o t h e r critical d a t a are n o t r e c o r d e d here because in this general w o r k precise values are n o t relevant for the s t r a t i g r a p h y . T h e p i c t u r e that e m e r g e s reflects n o t only the available rocks a m e n a b l e to such analysis, b u t also the interest o f the investigators a n d the field a n d l a b o r a t o r y costs o f each d e t e r m i n a t i o n .

3.3

The rock frame

N e a r l y all k n o w l e d g e o f geological history, d e p e n d s o n the evidence p r o v i d e d by existing rock. I n d e e d (possibly differing) interpretations by m a n y w o r k e r s as to age, c o n t e m p o r a r y e n v i r o n m e n t a n d processes, p r e v i o u s l o c a t i o n a n d a t t i t u d e etc. m a y be referred to the s a m e r o c k s as p r i m a r y reference. It is t h e r e f o r e p a r a m o u n t to agree o n h o w all scientists m a y refer to p a r t i c u l a r r o c k in c o n v e n i e n t n a m e d r o c k units. F r o m the n a m e d units as listed, for e x a m p l e in section 3.4 a n d in t h e glossary a n d index in P a r t 4 it is e v i d e n t t h a t in even a small area such as S v a l b a r d the geologic c o m p l e x i t y is such t h a t s o m e h u n d r e d s o f units n e e d n a m e s . For many years, especially in the Old World, rocks were described as though their ages were known, or should be known, and this often depended on their contained fossils. The earlier descriptions in Svalbard focused on the fossil horizons, or niveaux, selected from the body of rock in which they occur. Nowadays the whole rock bodies are described. Hence a lithic (approximately, lithostratigraphic) code has developed, largely based on the early American codes. The trend is towards international standardization even for national surveys. This process is not yet complete. For example what is often taken as an international standard (Hedberg 1976) claims only to be a guide in which all contrary opinions expressed on controversial matters by the Subcommission were not referred (Harland 1977). So there is still some way to go. Having been party to other attempts at an international code (e.g. George et al. 1969; Harland et al. 1972) the principles adopted here and throughout this volume interpret the international consensus on matters which have hardly proved to be controversial. T h e r e l a t i o n s h i p b e t w e e n the r o c k (a) a n d the t w o time scales (b) a n d (c) is d e p i c t e d as follows. T h e r e is n o w a y t h a t (b) a n d (c) c a n be related except t h r o u g h (a). A n y o t h e r i n t e r p r e t a t i o n (x) m u s t also derive f r o m (a). Thus: (b)+-+(a)~(c) a n d ( a ) ~ ( x )

3.3.1

A lithic code

This section discusses a lithic c o d e - t o w a r d s an i n t e r n a t i o n a l c o d e for defining, n a m i n g a n d classifying local r o c k bodies or units. T h e c o n s i d e r a t i o n s are r e c o u n t e d n o t as a legal f i ' a m e w o r k c o m p e t i t i v e w i t h o t h e r codes, b u t r a t h e r to indicate t h o s e m a t t e r s w h e r e differences o f o p i n i o n or practice h a v e persisted a n d hence w h e r e this w o r k has m a d e choices a n d i n d e e d r e c o m m e n d a t i o n s . T o this e n d s o m e principles b e h i n d these choices are listed below. (a) The term litbic is used advisedly in preference to lithostratigraphic because in many minds the category 'lithostratigraphic' implies perhaps indefinite parallel systems of other units (biostratigraphic, magnetostratigraphic, chronostratigraphic etc.). The case here is that one neutral scheme only of rock units is necessary, indeed obligatory, and that all other geoscientific disciplines with their terminologies serve to qualify these lithic units in many different ways as in the above formula.

29

(b) The units should be capable of location in the field as mappable units and therefore recognisable to other workers. (c) The rock so classified should not be genetically based. Thus interpretation as to environment of formation (e.g. sedimentary, metamorphic, igneous) must not preclude any rock unit from the lithic code. (d) The units should be conterminous as in a map or section so that there is no overlap or gap between them. Consequently any observation could be related in space to a position in one unit itself identifiable geographically and in relation to other units. (e) Formal definition of a unit begins in some locality, large or small, with thickness and description of the boundary with adjacent units. Features that are convenient may be used to define and characterise a unit and distinguish it from adjacent units. Typically these are lithological (sandstone, limestone, basalt etc.) colour, resistance to denudation, obvious macrofossils, minerals, or geophysical parameters especially if the unit is not exposed or sampled. (f) The time-honoured principle of naming the unit from a local place name is appropriate. Once this has been done, unless there has been a radical weakness in the description, that name should remain attached to the package of rock originally intended whether or not it changes rank up or down from the primary formation. To allow the lithic system to be comprehensive, additional terms such as complex, suite, pluton, sheet may be useful and further division may be necessary by qualifiers (supergroup, subgroup). (g) In naming units or selecting named units some sympathy with those having used a name might well take some precedence over the absolute correctness of application of the geographical name. Brevity and ease of use in other languages are considerations. Nor should the temptation to 'correct' an established name be entertained. Thus the name should also be fixed from its first use and not changed with subsequent political, linguistic, genetic, chronostratic arguments or superior scientific knowledge. The name should thus not be translated or modified in another language other than by transliteration to a different alphabet. Thus once the name of a unit has been published with sufficient description to identify it that name shall have priority. Subsequent fuller descriptions, genetic interpretations, and minor modifications do not qualify to rename the unit. (h) Unpublished names in reports, dissertations etc. when significant work has been done should be used by later workers when publishing the work with formal names and then attached to the originally intended unit of rock as far as practicable, but the date of the unpublished work gives no priority. (i) The formation is the primary unit. A group can only be established from a combination of two or more formations from which it is defined. A member can only be a division of a formation. But greater knowledge may require more divisions which will probably enter at a lower rank and thus the rank of the superior units may be raised. The reverse process is also possible. (j) Hierarchy of named units is a convenient convention. Formations may be grouped in groups, supergroups or subgroups or divided into members or beds in which the division need not be exhaustive. One advantage of hierarchies of names is that each scientist may choose or discover at what level memory serves for the task in hand. (k) Formational boundaries may be expected to be diachronous, whether or not this can be demonstrated, and thus attempts to revise a lithic system to fit time intervals should be resisted not least because time correlation is a matter of changeable opinion. (1) On the other hand if two parts of a formation are shown to have widely discrepant ages it may be suspected that the body could not once have been contiguous so that an additional named unit may be necessary for that part not in the primary definition. In this case the original name should remain with the rock originally or significantly applied. (m) Multiplication of names in any discipline is unpopular and the limitations of memory are often quoted in favour of fewer items. There is a scientific principle in favour of splitting rather than lumping, at least in the first stages of description. That is because if later the splitting proves to have been mistaken then combination of entities is easily applied retrospectively. The other way round, at a later stage to split a lump, may require that the lump then needs redescription by characters not evident in the earlier literature. (n) Disuse of names may be recommended in favour of some better scheme. But names cannot be suppressed except within an organization. Falling into disuse is a more equitable fate. (o) Conversely the use of new names or schemes cannot be obligatory except within an organization. They are essentially recommendations whose use may depend on their perceived scientific merit.

30

CHAPTER

Ma

WJST

WJNT

NDKT

O2LT

BHFT Richarddalen

WNWT I (4) 325 ( ~

NFWT

NFET

NAET t

CHRONOSTRAT 332

I

Vis

-- 350 -- 360

(11)347

(3) 346 I ~ (3) 351 ~ - - 349

(11)358

(2) 358

-- 370 (1) 375 (1) 379 [1) 380(9) 38( (3) 380 (3) 390 (4) 389 (1) 390 (3) 394

(3) 382

-- 390

(3) 385

i (1) 392 ( ~ (1) 395 ( ~

(1) 397

-- 400 (16) 402

(31) 404

(11) 407 (6) 410

4 1 0

-- 420 -- 430

(6)431 15)433 22)436

-- 440

(3) 409.5 (33)413 ~ (16)413 (10) 414 ~_) (15) 420 (33) 4 2 3 (15)425 }16{ 428 (3) 429 429 (9) 430 (15)433 (~) (16)437 (1) 439 (4) 438.5 (3) 443

(16) 410 ' (16) 418 (16) 420 (16) 423 (16) 430 (1)433 (16) 443

(32) ?

- - 377 (2) 381 Giv (3) 385 (~) Eif (2) 387 - -

(2) 396

Ems

(1)413 ( ~

Pra

(27) 4 2 4 (4) 427 (4) 430 (4)434

4) 422 1)425 (1)426 ( ~ (4) 428.4 (32) 432 (~)

(2) 411 (2) 415 (4) 419.3

Lok

417pr i Lud Wen -

(4) 442.6

(34) 442

4 4 3 - Ash

- -

Crd 458 LIo

(16) 455

- -

(33) 461

(11)462 (17) 4 6 6

-- 470

(11) 481

02

Tin

- - 470

(11) 472

-- 480

S Lly

-- 450 -- 460

D2

3 9 1

_

(25) 410 (28)

141442444

(4) 390 (3) 395 (4) 398 (3) 4O0 (3) 405

(24) 4 7 6 (6) 479 (6) 484

Arg

(16) 481

O1

- -

Tre

-- 490

-- 495 -- 500 --

D3

Frs

(5) 376

!

O1

Tou

(3)361 ( ~ - - 3 6 2 . 5 ~ - - - (3)366 ( ~ - - 3 6 7 ram

(3) 370.5

-- 380

- -

NAWT

"]'ADLT 1 1(4) 3151

(11)337

-- 340

3

(16)500 (16)504

(29) 500

-

Mer

-'~3

5 1 0

StD -- 520

-'~2

--518 -

(12)520

-

- - 525 -- 530

Atd

-- 534 (1) 538 (16) 542

- - 540

Tom Man

-- 545 (4) 549

--550 i (33).56.1

555.55-'(4)565 --600 (4)594 -

(2) 556 (14)620 (14)661

(6) 631

"~ 1

(13)600

(23) 624

-

Edi

V2

-- 580 ~ 610

V,

-

(34)677

--700 ~

Stu (8) 766

(4) 789.5 (4) 822.5

--800

- -

8 0 0 -

z

--900

(33) 952 - - 1 0 0 0 - - - -(34) o (22) "~ (22) - - 1 2 0 0 ~ (34)

1100 1130 1135 1200

Kar

(25) 939 14) 955 14) 965

(33) 1050 (36) 1190"

/",11399 1435

-- 1400 i

(35) 1317"

- - 1 0 5 0 ~ Yur

(35) 1735 (28) 1737 ( ~ (18)

--1800 o

(4) 1937

R2

(7) 1275 - - 1 3 5 0 Bur

-- 1600--

R 3

970

R1

--1650--

1750

(31) 1766 (19) 1800

--2000

Animikean

(24) 2121 - - 2 2 0 0 ~ (34) 2200 - - 2400

--2200-Huronian

(20) 2400 -

(23) 2415

(20) 25o0

--2600

Randian

- - 2800

- -

3000~ <

- - 2 4 5 0 - -

- - 2 8 0 0 - (14) 3234 Swazian

--3200

SVALBARD'S GEOLOGICAL FRAME

3.3.2

Some practical stratigraphic conventions in this work

(a) Order of treatment. The primary source of data is the rock as it exists today. When it may be useful to distinguish observation from interpretation, the rock succession, especially if stratified, is described from the top down. This orders the observations as they are seen in the field, drawn in a section, tabulated, or taken from a well log. Descriptive prose may then merge into notes or tables. The order thus stands independently of where descriptive divisions happen to fall. This is applied in Part 2 (Chapters 4-11). However, for interpretation as to age, environment, province etc. the order is in time sequence as is applied in the historical Chapters 12-22. (b) Selection and simplification. Because of the thousands of descriptions of successions, often several for the same locality, the reader needing detailed information must go back to original sources. The key publications are generally cited. Here will be found only generalized sections described in tabular form rather than illustrated in sedimentary logs. (c) Lithic character. The dominant lithic character of a named unit is not a necessary part of its formal name, but is often as useful as the name for recognition in the literature. However, it adds to the wording and so may be included in parenthesis, or excluded for brevity; a consistent policy has not been practicable to adopt. Most lithological terms are commonly understood. Dolostone is preferred to dolomite for the rock rather than the mineral. Feldspathite has been used in the special sense of a rock with > 5 0 % feldspar to avoid implications as to the origin of rocks commonly referred to as gneiss. Palaeosome is the older element in a composite rock (e.g. migmatite) and protolith is the original rock from which a metamorphic rock was formed. (d) Stratigraphic lexicons. Perhaps most importantly, during the preparation o f this work the Committee on the Stratigraphy of Svalbard (SKS) from 1990 has been following such principles as indicated above to agree a list o f names with definitions. The scheme of names in this work has been adjusted to be consistent with the resulting recommendations so far as they have been decided. Happily few changes in this work have been necessary. The positive results of that exercise are indicated in the glossary and index of stratigraphic names in Part 4 by adding an asterisk to those names recommended by SKS. So far, however, those names include only units younger than Devonian. A more comprehensive yet incomplete list had been compiled by Gramberg, Krasil'shchikov & Semevskiy (1990) and this was translated as Norsk Polarinstitutt Report No. 74 in 1991 (Daltmann & M a r k 1991). This is a glossary or lexicon offering alternative names without preference and generally with useful information. Different rank or status of the same unit were often given separate

31

entries; with the exception of these alternatives the names are marked in the list in Part 4 by a dagger Cf)- A much earlier glossary of stratigraphic names in the literature was compiled by Major, Harland & Strand (1956) for the Lexique Stratigraphique International and the glossary was continued privately and formed the basis of the names listed in Part 4. (e) Where differences of opinion cloud the literature as to classification and nomenclature of rock units the principal justification leading to the favoured scheme should appear in an early section in the historical chapters, which scheme may be applied elsewhere in the volume without comment. Unless otherwise explained the latest name should have been applied even to rock units once named differently. (f) There is some confusion about palaeontology. It follows from the above (3.3.1) that palaeontological studies should neither lead to an alternative hierarchy of biostratigraphic units (as implied by some e.g. Hedberg 1976, pp.45-65, Nesten 1989 p. 30 and countered by Harland e.g. 1992) nor to the disqualification of lithic units if recognized in part by fossils. Palaeontology, like any scientific discipline, is liable to diverse applications (not least for biozones in chronostratigraphy), to new discoveries and to new interpretations. No more than sedimentology could it provide the basis for a stable system of lithic units.

3.4

Tectono-stratigraphic terranes and their sequences

This section attempts a comprehensive list of the principal lithic units and tectonic events in terranes that are distinguished for descriptive convenience. In this work the term terrane is used both in its original sense for 'a series, system or group of r o c k s ' . . . [of a region] (Oxford English Dictionary 1971) and for terranes that are also postulated to be allochthonous, or suspected to be so. Thus the terranes listed in this section are purely descriptive without palinspastic implication. In the following section (3.5) the same terranes are considered in combination as relatively far-travelled entities. There need be no confusion in general when the term is qualified e.g. basement terrane, metamorphic terrane, Jurassic terrane, exotic terrane, allochthonous terrane, or suspect terrane. Doren (1990) discussed the terminology arising from the terranological bandwagon. Earlier schematic plans for Svalbard geology may be mentioned. Notably Holtedahl's (1925) comparison of the structure of Britain and Spitsbergen in a prophetic map. Another quite different schematic representation by Sokolov et al. (e.g. 1973) typifies the traditional Russian approach.

Fig. 3.8. Svalbard chronometric record. Numerical age determinations plotted against three linear scales that change at 555.55 and 1000 Ma on the left, and on the right is the chronostratic calibration as used in this volume and given in Fig. 3.7. The eleven columns refer to the descriptive terranes as used in this work and as shown on the diagrammatic map (Fig. 3.9). Some of the earlier results are shown as individual determinations becaue of their wide scatter. Some later work with smaller errors are consolidated as in the original publication. These are relatively reliable and are printed in large digits. In consequence the number of entries plotted is not particularly significant. Indeed the plot is to indicate the data available. Interpretation is discussed in appropriate chapters. Therefore localities, errors, minerals analysed and analytic data with the necessary qualification are not copied from the source and only the isotopic methods are added to the list of references below. The references are given fully with all authors cited because the reference to each number is for the determinations rather than the interpretations. The numbers in brackets refer to the sources for the values given: (1) Hamilton, Harland & Miller (1962), Rb-Sr & K-Ar; (2) Hamilton & Sandford (1964), Rb-Sr; (3) Krasil'shchikov, Krylov & Aljapyshev (1964), K-Ar; (4) Gayer, Gee, Harland, Miller, Spall, Wallis & Winsnes (1966), compilation map and new K-Ar data; (5) Krasil'shchikov (1970), K-Ar; (6) Horsfield (1972), K-Ar; (7) Edwards & Taylor (1976), Rb-Sr; (8) Goroshov, Krasil'shchikov, Met'nikov & Varasavskaya (1977), Rb-Sr; (9) Ravich (1979), K-Ar; (10) HjeUe (1979), Rb-Sr; (11) Hauser (1982), K-Ar; (12) Ohta (1982b), Rb-Sr; (13) Lauritzen & Ohta (1984), Rb-Sr; (14) Peucat, Ohta, Gee & Bernard-Griffiths (1989), U-Pb, K-Ar, Sm-Nd; (15) Dallmeyer (1989), 4~ 39Ar; (16) Daltmeyer, Peucat & Ohta (1990), 4~ 39Ar; Rb-Sr; (17) Dallmeyer, Peucat, Hirajima & Ohta (1990), 4~ 39Ar; Rb-Sr; (18) Gee, Schouenborg, Peucat, Abakumov, Krasil'shchikov & Tebenkov (1992), U-Pb zircon; (19) Gavrilenko & Kamenskiy (1992); (20) Balashov, Fedetov, Skufkin, Sharkov, Kravchenko, Sherstobitova & Ul'yanenko (1992), Rb-Sr (in Russian); (21) Peucat, Dallmeyer & Tebenkov, in Ohta (1992), U-Pb zircon; (22) Ohta (1992), compilation and map; (23) Balashov, Larionov, Gannibat, Sirotkin, Tebenkov, Ryiingenen & Ohta (1993), U-Pb zircon; (24) Bernard-Griffiths, Peucat & Ohta (1993), U-Pb, Sm-Nd & REE; (25) Johansson (1994), U-Pb zircon; (26) Johansson, Gee & Larionov (1995), U-Pb zircon; (27) Gee & Page (1994), 4~ (28) Johansson, Gee, Bjrrklund & Witt-Nilsson (1995), U-Pb zircon; (29) Gee, Johansson, Ohta, Tebenkov, Krasil'shchikov, Balashov, Larionov, Gannibal & Ryungenen (1995), U-Pb zircon, Rb-Sr; (30) Balashov, Teben'kov, Ohta, Larionov, Sirotkin, Gannibal & Ryungenen (1995), U-pb zircon; (31) Larionov, Johansson, Tebenkov & Sirotkin (1995), U-Pb zircon; (32) Tebenkov, Ohta, Balashov & Sirotkin (1996); Rb-Sr; (33) Balashov, Peucat, Teben'kov, Ohta, Larionov & Sirotkin (1966), Rb-Sr & zircon; (34) Balashov, Peucat, Teben'kov, Ohta, Larionov, Sirotkin & Bjornerud (1996) Rb-Sr, U-Pb zircon; (35) Hellman, Gee, Johansson & Witt-Nilsson (1997), zircon Pb-evaporation*. (36) Gee & Hetlman (1996), zircon Pb-evaporation*; (numbers 35 and 36) refers to minimum age of detrital zircon--maximum age of metasediments.

32 3.4.1

CHAPTER 3 the Liefdefjorden Supergroup, which may contain Silurian rocks, and excludes latest Devonian strata that belong to the cover sequence.

The terranes and their sequences

The terranes are listed in two parts: pre-Carboniferous and postDevonian.

basement sequences. In this sense terranes are shown on the Fig. 3.9

The reason is that the post-Devonian strata, while varying in different areas, nevertheless form a coherent sequence that can easily be correlated, and is only significantly interrupted by Paleogene tectonism. It is referred to as the 'cover sequence'. On the other hand, the pre-Carboniferous rocks are often difficult to correlate and have been given quite different nomenclatures in different terranes. This is contrary to some usage in which basement commonly refers to the more highly tectonized pre-Devonian rocks. In that case the Devonian rocks are neither basement nor cover, forming during the later Caledonian movements. At the same time Devonian is used loosely for

with acronyms, a shorthand used in tables and maps in this work. The tectonic significance, if any, of these terranes will be discussed in the following Section 3.5. To complete this list for convenient stratigraphic reference the cover sequences are divided into four main terranes: the Eastern Platform, the Spitsbergen Basin, the Graben, and Bjornoya. The subterrane sequences are listed. To keep the list within manageable bounds, divisions of rank lower than formations are omitted as are supergroup names of the cover sequence. The latter are as follows: Van Mijenfjorden Group (Paleogene) Nordenski61d Land Supergroup Adventdalen Group (Jurassic-Cretaceous) Kapp Toscana Group (Triassic-Jurassic) Sassendalen Group (Triassic) Bfinsow Land Supergroup Tempelfjorden Group (Late Permian) Gipsdalen Group (Carboniferous-Permian) Billefjorden Group (Latest Devonian-Carboniferous) Liefde Bay Supergroup Andr6e Land Group (Early to Early-Mid-Devonian) Red Bay Group (Early Devonian) Siktefjellet Group (?Latest Silurian)

Kvitoya

v,

%"

T Z

BFZA'~'~NAWz"

The pre-Carboniferous successions are thus referred to here as

NAET

Nottvedt et al. (1993) gave an overview and correlation of the cover sequence with that beneath the Barents sea. Thicknesses are intended to give some idea of the nature of the successions. Similarly ages are for guidance and not for application. A. EASTERN BASEMENT TERRANES

NORDAUSTLANDET EASTERN TERRANE (NAET) Franklinsundet Gp Djevlaflota Fm Rijpdalen granites etc Kapp Hansteen Gp Svartrabbane Fm Brennevinsfjorden Gp Helvetsflya Fm Duvefjorden Cpx migmatites and protoliths of metasediments including amphibolites = Duvefjorden Complex.

ESP NDKTj

,,~.

ese

'(BEPT)'~

WJNT 0

4

IHoP?

WJST,

rW

B O] P~~BOB

9

T 121"

,

,1~, 124"

, 1

Fig. 3.9. Tectono-stratigraphic terranes of Svalbard as used in this work. Eastern basement terranes: (NAET) Nordaustlandet Eastern Terrane;

(NAWT) Nordaustlandet Western Terrane; (NFET) Ny Friesland (including Olav V Land) Eastern Terrane; (NFWT) Ny Friesland Western Terrane. Central basement terranes: (ADLT) Andr~e Land-Dickson Land Terrane; (BHFT) Biskayerfonna-Holtedahlfonna Terrane; (WNWT) Northwest Spitsbergen Terrane; (HSDT) Hornsund Terrane. Western basement terranes: (PKFT) Prins Karls Forland Terrane; (FSGT) Forlandsundet Graben Terrane; (O2LT) Oscar II Land Terrane; (NDKT) Nordenski61dkysten-Nordenski61d Land Terrane; (WJNT) NW Wedel Jarlsberg Land-North of Torellbreen Terrane; (WJST) SW Wedel Jarlsberg Land-South of Torellbreen Terrane. Southern basement terrane: (BOBT) Bjornoya Basement Terrane. Cover terranes (post-Devonian sequences): (CBT) Central Basin Terrane; (NBT) North Basin Terrane; (WBT) Western Fold Belt/Basin Terrane; (SBT) Southern Basin Terrane; (NAPT) Nordaustlandet Platform Terrane; (OVPT) Olav V Land Platform Terrane; (BEPT) Berentsoya and Edgeoya Platform Terrane; (KKPT) Kong Karls Land Platform Terrane; (HOPT) Hopen Platform Terrane; (BOPT) Bjornoya Platform Terrane; (MSB) Main Spitsbergen Basin; (ESP) Eastern Svalbard Platform.

NORDAUDSTLANDET WESTERN TERRANE (NAWT) Hinlopenstretet Supergp 2.4 km Oslobreen Gp 1 km Sparreneset Fm, carbonates (Ordovician) Krossoya Fm, carbonates, 800 m (Cambrian) Polarisbreen Gp 1.25 km Klackbergbukta Fm, 650 m shales (?Ediacara) Sveanor Fm, 300 m tillite (Late Varanger) Backaberget Fro, 290 m (Early Varanger) Murchison Bay Supergp, 6.5 km Roaldtoppen Gp, 1.25 km Rysso Fm 500 Celsiusberget Gp, 2.1 km Raudstup-Sfilodd Fm, 550 m Norvik Fm, 340 m Flora Fm, 1250m Franklinsundet Gp, 1.8 km Kapp Lord Fm, 1000m Westmanbukta Fm, 625 m Persberget Fm, 150 m Meyerbukta Gp in W; Austfonna Gp in E, 1.3 km Innvikhogda Fm, 400+ m Djevlaflora Fro, 800+ m basal quartzite Fro, 0-100+m Kapp Hansteen Gp, 2000 m Norgekollen Fro, quartz porphyrites, porphyrite Gerardodden Fm, andesites, tholiites, volcanics and intrusives Orogenic episode = Botniahalvoya unconformity

SVALBARD'S GEOLOGICAL FRAME Brennevinsfjorden Gp, 3000 + m arenites and argillites paragneiss and palaeosomes in migmatites and granites (ofmid-Paleozoicage) NY FRIESLAND (INC. OLAV V LAND) EASTERN TERRANE (NFET) (Tournaisian unconformable cover). Late tectonic granite plutons Ny Friesland Orogeny Hinlopenstretet Supergp, 2 km (Cambro-Ord.) Oslobreen Gp, > 1.2 km, carbonate: (Arenig to Early Llanvirn) Valhallfonna Fm, 220 (?Late & Mid-Canadian) Kirtonryggen Fm, 750 m (Early Cambrian) Tokammane Fm, 192m (Vendian) Polarisbreen Gp, 0.7 km (Ediacara) Dracoisen Fm, 245 m (Late Varanger) Wilsonbreen Fm, 160 m (Early Varanger) Elbobreen Fm, 362m Lomfjorden Supergp, 6 km, Akademikerbreen Gp, 2.0 km, all carbonates Backlundtoppen Fm, 360-700 m carbonates Draken Fm, 25-300 m carbonate conglomerate Svanbergfjellet Fm, 100-625 m (Sturtian) Grusdievbreen Fm, 865 m (700-800 Ma) Veteranen Gp, 3.8 km, mainly siliciclastic Oxfordbreen Fro, 550m Glasgowbreen Fm, 540m Kingbreen Fm, 1500m quartzites with limestones (800-900 Ma) Kortbreen Fm, 1200m conformable on Vildadalen Fm NY FRIESLAND, WESTERN TERRANE (NFWT) (Tournaisian unconformable cover) Ny Friesland (Caledonian) Orogeny Stubendorffbreen Supergp, 11 km+ Planetfjella Gp, 4.7 km Vildadalen Fm, 3250m Flgten Fm, 1500m unconformity Harkerbreen Gp, 3.5-4.0 km Sorbreen Fm, 250+ m, psam, qi & amph Vassfaret Fm, 600 m quartzites and amphibolites Bangenhuk Fm, 200 m granitoid Rittervatnet Fm, 350m semipelites, amphs, feldspathites Polhem Fm, 900+ m psammites unconformity Instrumentberget-Fl~ttan granitoid Finnlandveggen Gp, 2.7+ km Smutsbreen Fm, 1200+ m, peliles & marbles Eskolabreen Fm, 1500+ m gneissose feldspathites & amphibolites ?AustJjorden tectonothermal event

(1750 Ma) (<1317Ma) (1750 Ma) (< 1190 Ma) (1750 Ma) (?2415 Ma?)

B. CENTRAL BASEMENT TERRANES ANDRI~E LAND-DICKSON LAND TERRANE (ADLT) (Tournaisian unconformable cover) Svalbardian tectogenesis Liefde Bay Supergp Andr6e Land Gp, c. 6+ km (Frasnian, Mimer Valley Fm, 740 m in South Dickson Land, Givetian & Eifelian) (Givetian) Wijde Bay Fm, 500-600 m (Eifelian) Grey Hoek Fm, 1000m (Emsian, Late Pragian) Wood Bay Fm, 3000 m BISKAYERFONNA-HOLTEDAHLFONNA TERRANE (BHFT) Andr6e Land Gp Wood Bay Fm in south unconformity folding Red Bay Gp, 3.7+ km Ben Nevis Fm, 900 m Fr~enkelryggen Fm, 600-750m Andr6ebreen Fm, 1400m Rivieratoppen Fm, 500-700m

(Early Pragian)

Syn-depositional Haakonian Diastrophism

33

Siktefjellet Gp, c. 3.5 km (?Silurian) Albertbreen (sandstone) Fm, 1400-3050m Lilljeborgfjellet (conglomerate) Fm, 100-400 m Rabotpasset (conglomerate) Fm, ?100 m Siktefjellet and Red Bay Groups rest on unconformity represented by Smeerenburgian (Caledonian) Orogeny Krossfjorden Gp, 6+ km (Proterozoic) Lerneroyane Fm, 1500m mainly marble Biskayerhuken Fm, 3.5+ km, mainly pelites Montblanc Fm, 850-1000m pelites, qtz-amphibolites and gneiss pass laterally down into migmatites containing Smeerenburgian neosomes and minor intrusions Richarddalen Orogeny (970 and ?3234 Ma) Richarddalen Gp (Proterozoic-?Archean) complex of eclogite, mylonitic reworked metagranite, metabasic and ultrabasic rocks, gneiss and marbles WESTERN NORTHWEST TERRANE (WNWT) Andr6e Land Gp (Early Devonian) Wood Bay Formation - S of Kronebreen (Lochkovian) Red Bay Gp Conglomerates in graben N of Kongsfjorden unconformably on Generalfjella Fm (Devonian-Silurian) Hornemantoppen (granite) Batholith in N Smeerenburgian tectonothermal orogeny (Proterozoic) Krossfjorden Gp, 7.5-13 km Generalfjella Fm, 2.5 km, marbles and pelites Signehamna Fm, 2-2.5 km, mainly pelites Nissenfjella Fm, 2-3 km, pelites with amphibolites pass down into Smeerenburgian migmatite complex Kollerbreen Fm, 8-10 km Waggonwaybreen Fm, 3 km containing Smeerenburgian neosomes and intrusions HORNSUND TERRANE (HSDT) (E Wedel Jarlsberg Land, SW Torell Land, and E Sorkapp Land) incl. Gipsdalen Gp (Early Permian-Pennsylvanian) Hyrnefjellet Fm, 270+ m unconformity: Adriabukta Folding Billefjorden Gp (Mississipian) Adriabukta Fm, 300 m unconformably on [Andr~e Land Gp] (Mid-Early Devonian) Marietoppen Fm, 1100m (Emsian-Siegenian) tectonic lower contact Hornsund Supergp Sorkapp Land Gp, 1.4+ km Arkfjellet (lst) Fm, (age?) Hornsundtind (lst) Fm, 480 m (Late Canadian) Negerbreen (lst) Fm, 120 m Dusken (lst) Fm, 100 m ?Unconformity Luciapynten (lst) Fm, 400 m Wiederfjellet (qi) Fm 300 m ?Hornsundian unconformity Sofiekammen Gp, c. 1 km Nordstetinden (dst) Fm, 150 m Gngdberget (marble) Fm, 250-300 m Slaklidalen (lst) Fm, 10-120m Vardepiggen Fm, 130-215 m (Late Early Cambrian) Bfftstertoppen (dst) Fm, 100-150m ?Jarlsbergian unconformity [Sofiebogen Gp], c. 4.4 km (Vendian) G~shamna in S & Bogstranda in N (phyllite) Fm, 2.5-3.0 km, (Vendian) ?Ediacara Fannytoppen (dst) Fm, 100 m (?Ediacara) Fannypynten (tilloid) Fm, 500 m (Late Varanger) unexposed unit, 300 m Hansvika (tilloid) Fm, 500 m (Early Varanger) tectonic contacts with Gn~lberget (marble) Fm H6ferpynten (dst Fm) 710m (Late Sturtian) ?Orogeny Magnethogda Gp (Proterozoic)

34

CHAPTER 3 C. WESTERN BASEMENT TERRANES

PRINCE KARLS FORLAND TERRANE (PKFT) Grampian Gp, 2.7 km Geddesflya Fro, 1800 m quartz, siltstone, turbidites Fugelhuk Fm, 400 m massive quartzite Barents Fm, 500 m siltstone, slate turbidites Sutorfjella Conglomerate Mbr Conqueror Fm, 850m

(?Silurian)

Tectonic episode

Utnes Fm, 80 m mainly slate Scotia Gp, 1 km Roysha Fm, 400 m dark slate Kaggan Fm, 300 m green & purple slate Baklia Fm, 200-300 m dark slate & carb (Ediacara) (=Black Shale Fm of Knoll & Ohta 1988) Peachflya Gp, 1.3 km Knivodden Fro, 400 m grey & green phyllite Hornnes Fm, 350 m phyllite sandstone and 1st Alasdairhornet Fm, 190m tufts and lava flows Fisherlaguna Fm, 350m dark phyllite Geikie Gp, 0.8 km Rossbukta Fro, 300 m dark phyllite Gordon Fm, 470 m dst, 1st, phyllite Ferrier Gp, 1.1 km Neukpiggen Fm, 300 m Peterbukta Fro, 100m psam. sch. & stones (Late Varanger) Hardiefjellet Fm, 120-500 m psammitic schist & stones (Late Varanger) Isachsen, Fm, 150+ m quartz chlorite schist base not seen tectonic contact

Pinkie Fro, 200+ m metavolcanics

(?Early Varanger)

FORLANDSUNDET GRABEN TERRANE (FSGT) Buchananisen Gp, c. 6 km Balanuspynten Fm, 1650+ m Aberdeenflya Fm, 2800+ m McVitiepynten Subgp Marchaislaguna Fm, 55-600+ m Krokodillen Fm, 400+ m Reinhardpynten Fm, 210+ m Sesshogda Fm, 120+m Selvgtgen Fm, 40-170 m

(Late Paleogene)

OSCAR II LAND TERRANE (OIILT) Billefjorden Gp, c. 0.5 km Vegard Fm, 30-360 Orustdalen Fm, c. 100 m

(Mississipean)

Unconformity

Bullbreen Gp ?Sarsoyra Fm, 450 m Holmesletfjella Fm, 150+ m Bulltinden Fm, 60 m Motalafjella Fm, 260 m

(?Silurian) (Early-mid Silurian) (Mid Late Ordovician)

unconformity = Eidembreen tectogenesis

Vestg6tabreen Complex tectonic contact

Comfortlessbreen Gp, c. 6 km Aavatsmarkbreen Fm, I km, phyllite Annabreen Fro, 2 kin, quartzite Haaken Fm, 2~3 km, tillite conformable contact St Jonsfjorden Gp, c. 4 km Alkhorn Fm, 1 km Lovliebreen Fm, 1 km, Moefjellet Fm, 500-800 m Trondheimfjella Fm, 1300 m

(Vendian) (?Ediacara) (Late Varanger)

(Early (Early (?Early (Early

Varanger) Varanger) Varanger) Varanger)

NORDENSKIOLDKYSTEN (NORDENSKIOLD LAND) TERRANE (NDKT) Kapp Linn6 Fm, 2.5+ km, granitoid tiUite (Late Linn~fjella unit, 2+ km, ph.qi & 1st Malmberget unit, 1st marbles, semi-pelites, qi (Early Lhgnesbukta Gp, ?3+ km (Early Lgtgneset Fm, schistose tillite, 350-450 m, Gravsjoen unit various metasediments & basites Lgtgnesrabbane Fm, 1-2km, (Early Kapp Martin Fm, 800 m, cgls & phyllite

Varanger) Varanger)

Varanger)

NW WEDEL JARLSBERG LAND (NORTH OF TORELLBREEN) TERRANE (WJNT) (Late Varanger) Kapp Lyell Gp, 3 km, (Late Varanger) Lyellstranda Fm, 1.3 km, Logna Fm, 0.2km, phyltite (Late Varanger) Dundrabeisen Fm, 1.4km, Konglomeratfjellet Gp----(Early Varanger) Dunderdalen Fm in W phyllites & minor olistoliths = Chamberlindalen Fm, 2 km, in E phyllite & basic volcanics Slettfjelldalen Fro, in W = Solhogda Fm, in E Floykalven Fm, in W 0.5 kin, diamictite = Gaimardtoppen Fm, in E 0.7 km, cgl, sst, 1st Thiisfjellet Fm, 0-100m black pyritic 1st 0-100 m in E local basal cgls 0-50 m in W unconformable base seen in W resting on Torellian Orogeny

(pre-Vendian)

Nordbukta Gp, c. 4 km Dordalen Fm, 150+ m banded dst, 1st marble Thiisdalen Fm, 200 m dark phyllite Trinutane Fm, 380m Seljehangfjellet Fm 700 m sandy dst Botnedalen Fm, 300 m play 1st, dst & phyllite Peder Kokkfjellet Fm, 60 m sandy dst Evafjellet Fm, I km, qi & phyllite Kapp Berg Fm, 1+ km, ph + qi

SOUTHWEST-WEDEL JARLSBERG LAND (SOUTH OF TORRELLBREEN) TERRANE (WJST) (modified from Birkenmajer 1993, Czerny et al. 1993, Harland et al. 1993) (Early Varanger) Aust Torellbreen Gp Slyngfjellet Fm Deilegga Subgp 3.5 km Bergskardet Fm 500+ m Bergnova Fm 1800 m Tonedalen Fm 1200+ m Vimsodden Subgp, 2 km Jens Erikfjellet Fm l l00m Elveflya Fm 900 m Tectonothermal event c. 950 Eimfjellet Gp (Czerny et al. 1993), 4+ km Pyttholmen Fm [Nottinghambukta Fm] 1550 m (Mesoproterozoic) Gulliksenfjellet Fm, 500-850 m Bratteggdalen Fm Steinsvikskardet 100~50 m Sk~lfjellet Fm, 950-1400 m (Mesoproterozoic) Eimfjellbreane Fm Skjerstranda Fm Isbjornhamna Gp, 2850+ m (Mesoproterozoic) Revdalen Fm, 250-350 m Ariekammen Fm, 1500+ m Skoddefjellet Fm, 1000+ m Tectonic contact

Dunoyane Fm, 750m D. SOUTHERN BASEMENT TERRANE

?concordant contacts

Kongsvegen Gp Mtillerneset, 2 km, semi-pelite, south of St Jonsfjorden North of Engelskbukta are Bogegg Fm, 1.5 km, semi-pelites with dol-qi. Steenfjellet, Fm 0.1 km, marbles, N of Engelsbukta Nielsenfjellet Fm, 2.5 km, schistose, base not seen

Varanger)

(Late Sturtian)

BJORNOYA BASEMENT TERRANE (BOBT) Caledonian tectogenesis

Ymerdalen Gp, c. 0.65 km Antarcticfjellet Fm, 240+ m Perleporten Fm, 400+ m unconformity

(Canadian) (Early Caradoc)

SVALBARD'S GEOLOGICAL FRAME Bjornoya Gp, c. 0.6+ km Sorhamna Fm, 175+ m Russhamna Fm, 400+ m [part of Barents sea] E. COVER TERRANES (post-Devonian sequences) CENTRAL BASIN TERRANE (CBT) Van Mijenfjorden Gp, 1.5-2.5 km Aspelintoppen Fro. 1000+ m (CB6) Battfjellet Fro, 60-300 m (CB5) Frysjaodden Fro, 200-400 m (CB4) Grumantbyen Fm, 45-200 m (CB3) Basilika Fro, 10 350m (CB2) Firkanten Fro, 100-170m (CB1) Adventdalen Gp, c. 2 km Carolinefjellet Fro, 270-1214+ m Helvetiafjellet Fro, 53-100 m Janusfjellet Subgp Rurikfjellet Fm, 176-342 m Agardhbukta Fm, 243 m Kapp Toscana Gp, 253 m Wilhelmoya Fm, 1-50 m De Geerdalen Fm, 190 m Tschermakfjellet Fm, 63 m Sassendalen Gp, 725 m Botneheia Fm, 157 m Sticky Keep Fm, 230 m Vardebukta Fm, 254 m Tempelfjorden Gp Kapp Starostin Fm etc. below surface

(late Varanger, Vendian) (earliest Vendian)

(Paleogene) (Eocene)

(Paleocene)

(Early Cretaceous)

(Rhaetian) (?Norian) (Triassic)

(Permian)

NORTH BASIN TERRANE (NBT) Sassendalen Gp, 316m (Triassic) Botneheia Fm, 100 m Sticky Keep Fm, 130 m Vardebukta Fm, 86 m Tempelfjorden Gp, 381 m (Permian) Kapp Starostin Fm, 381 m Gipsdalen Gp, 850 m (Permian-Pennsylvanian) Dickson Land Subgp Gipshuken Fm, 211 m Wordiekammen Fm, 180 m Campbellryggen Subgp (Pennsylvanian) Minkinfjellet Fm, 156 m Ebbadalen Fm, 281 m Hultberget Fm Billefjorden Gp (Mississippian) Mumien Fro, 127 m H~rbyebreen Fm, 189 m resting unconformably on (Svalbardian deformed rocks) Andr6e Land Group in W and Stubendorffbreen Supergp in E WESTERN (FOLD BELT) BASIN TERRANE (WBT) (NORTHERN) Van Mijenfjorden Op (Paleocene) Ny-Alesund Subgroup, 240 m Broggerbreen Fm, 120+ m Kongsfjorden Fm, 120 m Sassendalen Gp (Early Triassic) Vardebukta Fm, 0-50 m Tempelfjorden Op (Late Permian) Kapp Starostin Fm, 1200m Oipsdalen Gp (Early Permian-Pennsylvanian) Dickson Land Subgp Gipshuken Fro, 88-146 m Wordiekammen Fm, 160-290 m Morebreen Mbr, 130m Charlesbreen Subgp (Pennsylvanian) Scheteligfjellet Fm, 153 m Br;~ggertinden Fm, 360 m Billefjorden Gp. (Mississippian) Vegardfjella Fro, 30 m Orustdalen Fm, c. 100 m resting unconformably on Kongsvegen Gp and Comjortlessbreen Gp

35

WESTERN (FOLD BELT) BASIN TERRANE (WBT) (CENTRAL) Van Mijenfjorden Gp (Paleogene) Firkanten Fm, 100+ m Adventdalen Gp, c. 1 km E. Cret.-L. and M. Jurassic) Carolinefjellet Fm, 180 m Helvetiafjellet Fm, 150 m Janusfjellet Subgp, 710 m Rurikfjellet Fm, 400m (Early Cretaceous) Agardhfjellet Fm, 310 m (Late and Mid-Jurassic) Kapp Toscana Gp, 330m (Late Triassic) Wilhelmoya Fm, 30 m De Geerdalen Fm, 300 m [Tschermakfjellet Fm, 0 m?] Sassendalen Gp, 1.4 km (Mid- and Early Triassic) Botneheia Fm, 400 m (Middle Triassic) Sticky Keep Fm, 400 m (Early Triassic) Vardebukta Fm, 600m Tempelfjorden Gp, 500 m Kapp Starostin Fm, 500m (Permian) Gipsdalen Gp Dickson Land Subgp, 400-600 m (Early Permian Late Permian) Gipshuken Fm Workiekammen Fm Charlesbreen Subgp, c. 600 m (Early Pennsylvanian) TSrnkanten Fm, 251 m Petrellskaret Fm, 350 m Billefjorden Gp, 1.1 km (Mississippian) Vegardfjella Fm, 358 m Orustdalen Fm, 759 m resting unconformably on basement SOUTHERN BASIN TERRANE (SBT) Kapp Toscana Gp (Late-Mid-Triassic) Wilhelmoya Fm, 60 m De Geerdalen Fm, 31 m Tschermakfjellet Fm, 16 m Sassendalen Gp (Mid-Early Triassic) Botneheia Fm, 60 m Sticky Keep Fm, 90 m Vardebukta Fm, 60 m Tempelfjorden Gp (Late Permian) Tokrossoya Fm, 300+ m Gipsdalen Gp (Early Permia~Pennsylvanian) Treskelen Subgp Treskelodden Fm, 170 m Hyrnefjellet Fm, 270 m Billefjorden Gp (Mississippian) Sergeifjellet Fm, 260 m Hornesundneset Fm, 720 m Adriabukta Fm, 300m NORDAUSTLANDET PLATFORM TERRANE (NAPT) Kapp Toscana Gp (Late Triassic) De Geerdalen Fm, 50+ m Sassendalen Gp (Mid- and Early Triassic) Barentsoya Fm, 118 m Tempelfjorden Gp (Permian) Kapp Starostin Fm, 91 m Gipsdalen Gp (Early Permian-Late Pennsylvanian) Dickson Land Subgp Gipshuken Fm (Sorfonna Mbr and Zeipelodden Mbr), 121 m Wordiekammen Fm (Idunfjellet Mbr), 150 m Harbardbreen Fm, 15-50 m OLAV V LAND (& WILHELMOYA) PLATFORM TERRANE (OVPT) Janusfjellet Subgp Agardhfjellet Fm, 50+ m (Late and Mid-Jurassic) Kapp Toscana Gp (Late Triassic) Wilhelmoya Fm, 119 m De Geerdalen Fro, 254m Tschermakfjellet Fm, ?34+ m Sassendalen Gp (Mid-Early Triassic) Barentsoya Fro, ?

36

CHAPTER 3

Tempelfjorden Gp Kapp Starostin Fro, 140+ m Gipsdalen Gp Dickson Land Subgp Gipshuken Fm, 140-179m Wordiekammen Fm, 170 m Maltebrunfjellet Fm, 60-70 m

(Late Permian) (Early Permian-Pennsylvanian)

BARENTSOYA AND EDGEOYA PLATFORM TERRANE (BEPT) Kapp Toscana Gp (Late Triassic) Negerfjellet Fm, 400+ m Edgeoya Fm, 130-165 m Sassendalen Gp (Triassic) Barentsoya Fro, 300 m Tempelfjorden Gp (Late Permian) Kapp Starostin Fm (Kapp Ziehen Mbr), 75+ m (Permian) deep wells: Plurdalen-1 Raddedalen- 1 Kapp Starostin Fm Gipsdalen Gp, c. 430 m (Early Permian Pennsylvanian) Gipshuken Fm Wordiekammen Fm Campellryggen Subgp, c. 1.9 km and ?Billefjorden Gp. (Mississippian) KONG KARLS LAND PLATFORM TERRANE (KKPT) Adventdalen Gp Kong Karls Land Fm, 72 m (Barremian) Kongsoya Fm, 170 m (Hauterivian-Pliensbachian) Kapp Toscana Gp Wilhelmoya Fm (= Svenskoya Fm), 196+ m (?Sinemurian-Rhaetian) HOPEN PLATFORM TERRANE (HOPT) Kapp Toscana Gp (Rhaetian) Wilhelmoya Fm = Lyngefjellet (sandstone) Mbr, 80+ m Flatsalen (shale) Mbr, 55+ m (?Norian) Iversenfjellet Fm, 290+ m = c. De Geerdalen Fm 270+ m deep wells: Hopen-I and Hopen-2 Tchermakfjellet Fm, c. 350 m Sassendalen Gp (Mid Early Triassic) Barentsoya Fm, c. 320 m Tempelfjorden Gp Kapp Starostin Fm, c. 230 m (Early Permian Pennsylvanian) Gipsdalen Gp Gipshuken Fm Wordiekammen Fm, c. 800 m Minkinfjellet Fm Ebbadalen Fm, 500m (Mississippian) Hultberget Fm BJORNOYA PLATFORM TERRANE (BOPT) (Triassic) Sassendalen Gp Skuld Fm, 135m (Late Mid-Triassic) (Mid-Early Triassic) Urd Fm, 65 m (Late Permian) Tempelfjorden Gp Miseryfjellet Fm, 115 m (Permian) group undecided Hambergfjellet Fm, c.100 m (Early Permian-Pennsylvanian) Gipsdalen Gp Kapp Duner Fm, 75 m Kapp Hanna Fm, 150+ m Kapp KSre Fm, 215 m Landnordingsvika Fro, 200 m (Mississippian) Billefjorden Gp Nordkapp Fm, 230 m (part Famennian) Roedvika Fm, 360 m

3.4.2

Combined sequence for Svalbard

From the successions listed above a number of tectonic episodes may be taken separately or listed together. By combining the diastrophic events it does not follow that they all occurred in a single Svalbard sequence, but it does open the mind to possible cot-

relations and connexions both within Svalbard and elsewhere, and it closes the mind to tectonic events elsewhere that appear to have left no mark in Svalbard. An example of such a negative conclusion is that Svalbard appears to show little evidence of the Finnmarkian phase (Early Cambrian) of the Caledonian Orogeny in Scandinavia (Sturt, Pringle & Ramsay 1978), if indeed such a phase is significant in this respect it sides with Greenland west of Iapetus. Archean and early Paleoproterozoic events are recorded in zircons in proto-basement rocks, but there are too few records to generalize. They are discussed in Chapter 12. Leaving these aside the following tectonic or thermal episodes are established. Late Paleoproterozoic igneous rocks systematically dated by zircons around 1750Ma are found in northeastern Svalbard (Ny Friesland and possibly in Nordaustlandet). These events might correspond to the Rinkian of East Greenland. Early Neoproterozoic zircons in volcanic and igneous rocks approximate 950 M a from northeast, north central and southern Svalbard. This widespread evidence suggests a late Grenvillian correlation in Laurentia. Undated diastrophism, certainly pre-Vendian, might correspond to the above or to later tectonic episodes in southwestern Wedel Jarlsberg Land and have been referred to Torellian and Werenskioldian events. Slight, late Vendian or early Cambrian, tectonism (Jarlsbergian) is recorded in the middle Hornsund region. Early to mid-Ordovician tectonism (the Eidembreen phase) is characteristic of central western Spitsbergen and appears to correlate with the M'Clintock orogeny of Pearya in Northern Ellesmere Island. Mid-Silurian time was the climax of a general Silurian tectonism (Ny Friesland Orogeny) in both northeast and northwest Svalbard and corresponds to the main Caledonian orogeny that united Baltica and Laurentia. Latest Silurian and Early Devonian events continued the Caledonian evolution as are evident in northern Svalbard. (a) (b) (c)

Ny Friesland granite emplacement; Smeerenburgian migmatic invasion of northwest Spitsbergen rocks followed by granite emplacement; disturbed sedimentation and tectonism in central north Spitsbergen (Haakonian).

These ?latest Silurian-earliest Devonian events may correlate with events in the Queen Elizabeth Islands (Trettin 1991, p. 337) where late Silurian sinistral transpression accreted Pearya to the Clements Markham, Northern Heiberg and Hazen fold belts. Similar deformation episodes took place in the Boothia and Inglefield uplifts where continued deformation is recorded into Lochkovian and Pragian time. The southern Urals witnessed strong compression about that time (Korinevskiy 1988). (d)

A pre-Wood Bay folding episode has been demonstrated by A. M c C a n n (pers. comm.) but not yet named.

Late Devonian (Svalbardian) tectonism affected much of north Spitsbergen. This Svalbardian episode may be related to Phase 5 and/or Phase 6 of Trettin (1991, p. 338) in the Innuitian Orogen as follows. (5) A Givetian(?)-Frasnian uplift of northwestern Hazen Fold Belt... is tentatively attributed to renewed sinistral strike-slip, and correlated with a second, poorly dated episode of compressional deformation in northern Axel Heiberg Island. (6) Extensive compressive deformation, known as the Ellesmerian Orogeny s e n s u s t r i c t o , occurred throughout the Franklinian mobile belt.., in latest Devonian-Early Carboniferous time .... The rocks deformed by the foregoing events are referred to as basement. The overlying rocks are cover and may be in basin or platform mode. Some would restrict the term basement to pre-Devonian rocks, whether or not Devonian strata with thicknesses up to 8000 m are present, and so match the earlier successions which are variable and often expose more than 8000 m.

SVALBARD'S GEOLOGICAL FRAME However, the cover sequence embraces all of Svalbard in a relatively uniform and coherent succession. It begins with the Billefjorden Group (Late Famennian through Serpukhovian), with minor basin formation associated with the earlier fault zones with sedimentary thicknesses up to 1250 m of grey fluvial/alluvial clastics. The mixed sequence of the Gipsdalen Group (Bashkirian to Artinskian) followed, totalling up to 1800 m. The earlier Subgroup (Campbellryggen) begins with red beds followed by evaporites continuing the separation into fault-bounded basins. This was followed by more extensive carbonates of the Dickson Land subgroup deposited over a more stable platform. That sequence reflected a transition from humid non-marine environments through red clastic and sabkha sedimentation and, with rising sea level, to shallow marine carbonates. The Tempelfjorden Group (up to 460 m Artinskian to Wordian) of silicified marine clastics with some carbonates reflects widespread stable conditions, with marine transgression promoting mature cool deep shelf environments. Minor diastrophism is evident especially in the Carboniferous sequence. It may be regarded as the waning phases of Caledonian tectonism or as a weak correlative of the Variscan movements. Svalbard, in its Arctic context, was remote from Variscan tectonism far to the south but possibly southern Spitsbergen recorded these effects more than further north. Birkenmajer (1994) noted Devonian-Carboniferous, Mississippian-Pennsylvanian and midPermian unconformities. The following three groups of Mesozoic strata continued relatively stable marine platform deposition, but with invasion by advancing deltas. The Sassendalen Group (latest Permian through Ladinian) comprises marine shales, verging on anoxic environments, upwards coarsening into sandstones in several episodes. The Kapp Toscana Group (Ladinian through ToarcianBajocian and little more than 500m thick) is characterized largely by deltaic sandstone incursions from the north and east into a marine environment. The Rhaetian-Liassic story differs in that the main sedimentation occurs in eastern Svalbard while most of Spitsbergen became a positive area recording only thin deposits. The Adventdalen Group is more complex (c. 550 to c. 1700m) beginning in the west with a Bathonian basal conglomerate the Jurassic strata are marine clastics. Around the Jurassic-Cretaceous boundary and well into Neocomian and even Barremian time minor diastrophism, renewing older fault activity, caused local disconformities after which basic igneous intrusion and volcanic activity was widespread especially in the east. The Aptian-Albian phase was one of major deltaic advance. Further south in the Barents sea floor 'Cimmerian' disturbances have been identified, especially by the petroleum industry. Strictly Cimmerian refers to the Tethys, but has been used loosely for almost any Mesozoic unconformity. Late Cretaceous slight tilting up to the north and erosion truncated the upper Adventdalen Group strata making a peneplain for the deposition of the basal conglomerates of the ensuing Van Mijenfjorden Group (Paleocene through Eocene and up to 3000m preserved (and ?2000m lost). Dominantly continental deltaic clastics with Paleocene coals prevailed but with a marine basin developing in central and west Spitsbergen. The West Spitsbergen Orogeny (mainly Eocene) is reflected in its early stages by the main sediment sources coming from new uplift in the west which then dominated the eastern deltaic advance. The orogen forms a belt in the west with thin-skinned thrusting and folding extending eastwards and causing renewed compressional structures along the ancient fault zones in the east. The orogeny was preceded and followed, if not accompanied, by graben formation along the west coast with sediment thicknesses up to more than 5000 m. Thereafter the main sedimentary record is confined to the sea and reflects the uplift and erosion of Svalbard. Quaternary deposits appear as a transient record in the dominantly denudational final chapters.

3.4.3

37

Sequence stratigraphy

The sequences outlined above are tectonically controlled. Sea level changes, of course, have tectonic and climatic origins; but sequences related to eustasy are on a finer scale. These already serve to distinguish some beds and members, but global correlation is generally inadequate to relate such relative changes of sea level to global changes and so to distinguish local diastrophism from the eustatic component. However, there are some notable global effects and these are mentioned elsewhere leaving the detailed discussion to the later chapters. In due course with finer discrimination such changes may aid in correlation; but that is perhaps for later work to accomplish. At present there is little obvious correlation between the sequence stratigraphy and eustatic curves of Shell's (1995) G e o l o g i c a l D a t a T a b l e - M e s o z o i c . In their Paleozoic table major anoxic events are noted (i) for Europe in Early Capitanian time (i.e. ?post-Kapp Starostin Fm) and the Svalbard hiatus may correspond to the southern hemisphere glaciation with reduced sea levels (ii) for Laurussia and N Africa in Late Frasnian time; and for earlier events not easy to relate to the Svalbard record. At a more local level sequence stratigraphy is a new name for current refinements in stratigraphic (sedimentological-tectonic) description.

3.5

Geotectonic interpretation

This section addresses some controversial matters of interpretation. Discussion with evidence will come later. The purpose here is to identify the problems and outline some possible solutions. This gives fair warning to sceptics to look closely at the evidence as it unfolds. It may be worth repeating that in this book, as well as in this chapter, description generally precedes interpretation, so that the information presented is not intended to be structured to favour one viewpoint. However, after discussion, working hypotheses are arrived at that are intended to be consistent throughout the work. The following discussion is against a background in which majority opinion opposed any idea of continental drift until about 1964 after which the Bullard et al. (1965) model, and its successive modifications, to restore the spreading of the Arctic and Antarctic oceans were widely accepted. Thereafter most geologists assumed that Svalbard had remained in its pre-Cenozoic position as an indivisible unit throughout its history and this led to elaborate assumptions about correlation of pre-Devonian successions. The most fixist (as distinct from mobilist) school remained in Russia. A typical interpretation of the structure of Svalbard is seen in that by Sokolov et al. (1973) in which its geological history is interpreted in global evolutionary phases based on Russian experience.

3.5.1

Provinces and allochthonous terranes

Historically Spitsbergen was a key element in some of the earliest speculations of continental drift. One problem was that geometrically by restoring the Spitsbergen and Greenland continental shelves to a pre-Atlantic fit two configurations were possible with Spitsbergen against Central East Greenland, as in Wegener's reconstruction (e.g. 1924, fig. 20/24) or against northern Greenland as in Taylor (1928) and du Toit (1937, p. 169). Although their maps were not precise, when the first detailed fits of the continental shelves were attempted as by Carey (1958, pp. 207-209) who placed Svalbard to the east, and Bullard et al. (1965) who placed it to the north, the ambiguity remained as was illustrated in Harland (1965, figs 1 & 2). The geometrical ambiguity was compounded by competing stratigraphic affinities. Having visited Eastern Greenland with Lauge Koch, after working on the pre-Carboniferous rocks of Ny Friesland, it was confirmed forcibly in my mind (as already

38

CHAPTER 3

indicated by Kulling) that the two sequences were too similar to be an accidental coincidence. This favoured the east Greenland location (e.g. Harland 1959, 1961). However, the work in CSE moved up the stratigraphic column in Svalbard. It then became equally impressive that the cover sequence of Svalbard showed very close affinity with that of the Queen Elisabeth Island sequences in the Canadian Arctic. This favoured a position north of Greenland. Moreover, it precluded an East Greenland connexion with Svalbard because of the contrasts between the Mesozoic, especially Triassic successions known personally in each place. Indeed the North Greenland position for post-Devonian time met so many other requirements that it was readily accepted by most scientists. The conflict of evidence was then resolved by moving Spitsbergen from off East Greenland by strike-slip motion (a late Caledonian episode) the 1000 or so kilometres to the preferred later position off north Greenland as was then proposed (Harland 1965). The Cambridge work then moved from eastern and central to western Spitsbergen to attempt the correlation of the Hecla Hoek succession in Ny Friesland with that of older rocks along the west coast. The contrasts were formidable and credibility had to be stretched if detailed correlation was to be entertained. Not only did the western older rocks contrast with eastern Spitsbergen, but also with eastern Greenland. They could not then have been between the two. Therefore extensive strike-slip within Spitsbergen seemed to be necessary, not only along the Billefjorden Fault Zone (Harland 1969), but also along a postulated fault running south from Kongsfjorden (Harland 1975c). The hypothesis was thus of three provinces in Svalbard separated by two major sinistral fault zones (Harland & Wright 1979). I had already suggested at the San Francisco Arctic Geology meeting (1972 and 1973b) that as a general possibility Paleozoic faults could have bounded ancient slices of lithosphere, as in the Western Cordillera of North America. For example Cenozoic strike-slip was later based on tectono-stratigraphic comparisons for displaced 'terranes' in western North America. We had used the term province and American geologists adapted the term terrane for this concept. Subsequently the term terrane has become fashionable. Thus the postulated three Svalbard provinces are allochthonous terranes with respect to each other and to Greenland. Nevertheless the original use of province has a distinct significance that may be worth preserving, albeit with some qualification. The Svalbard hypothesis was not only that the terranes were relatively far travelled, but by their affinity with now distant terranes, their provenance was specified. They had in common certain characteristics with those distant terranes which is the criterion of a province. Therefore our palinspastic hypothesis for pre-Carboniferous Svalbard is restated as follows. Three parts of Svalbard in late Proterozoic time belonged to three Greenland and Canadian provinces. (i) A Central East Greenland Province united the Central East Greenland terrane and the East Svalbard Terrane. (ii) A North East Greenland Province united a North Greenland terrane and a Svalbard Central Terrane. (iii) A North Greenland-Pearya Province united Pearya in Ellesmere Island, terranes of North Greenland and the Svalbard Western Terrane. During Paleozoic time, and related to the M'Clintock, Caledonian and Ellesmerian orogenies, sinistral strike-slip motion brought the three Svalbard terranes together, docking in Late Devonian time so forming a new Svalbard composite terrane that has persisted to this day except t h a t i t drifted from north of North Greenland through Cenozoic time to the present position. Many details and modifications will unfold in the following chapters (especially Chapters 15 and 16), including the probability of at least two subterranes for each major terrane and possibly a further terrane to the east. (Fig. 3.10a & b) A further modification may now be necessary with the work of Smith & Armstrong (1997) who find such similarity between Ordovician faunas in Bjornoya and in northeast Greenland that the fourth enigmatic southern (Bjornoya) terrane may have been attached to Greenland through Paleozoic time and only joined Svalbard as it progressed away from Greenland in Cenozoic time.

3.5.2

Differential horizontal lithospheric motions

The relationship, fit and misfit, of terranes with characteristic tectonostratigraphic sequences through Late Proterozoic and Phanerozoic time was the most powerful motivation in proposing major sinistral strike-slip components of Paleozoic horizontal motions between lithospheric plates. The sedimentological argument came into play with respect to the Billefjorden Fault Zone (Harland 1969). The eastern margin of the Devonian graben was conceived as a Late Devonian strike-slip fault truncating the original wider fluviatile apron (Harland 1969; Friend & Moody-Stuart 1972). The palaeomagnetic argument either way has proved too crude or uncertain, The kinematic argument is that differential motions between irregular plates throughout the Earth require not only opposing motion of convergence and extension, but strike-slip and oblique motions combining components of strike-slip, convergence or extension. It was thus necessary to reinterpret the remarkable linear structures of western Ny Friesland from the hypothesis of compression and escape tectonics (Harland & Bayly 1958; Le Pichon e t al. 1977; Ohta 1994) to a mechanism of transpression once significant strikeslip motion was required. Transtension, with pull-apart basins was a natural complement (Harland 1971). The argument for Cenozoic dextral strike-slip to separate Svalbard and the Barents Shelf from Greenland began with the need to bring Svalbard to its present position from its Mesozoic position along the De Geer Fault. This had the additional and rather precise support from magnetic signatures plotting the course of ocean spreading. Both transpression for the West Spitsbergen Orogeny and transtension for related pull-apart basins have been invoked, accepted by most and resisted, for a time at least, by others. In this connection it should be reported that, against prevailing opinion, papers by Hanisch (1984) and Lyberis & Manby (1993a, b) have argued that the structures of the West Spitsbergen Orogen were formed not by Eocene transpression during the dextral translation of Svalbard from north of Greenland to its present position but in Late Cretaceous time by the earlier compression of Svalbard by a northward moving Greenland. A consequence of their hypothesis is that the orogenic structures do not deform Paleogene strata, but are unconformably overlain by them. This can be settled by simple inspection at critical localities as pointed out by Lepvrier (1994), Harland (1995) and Maher et al. (1995) which give more detail to support the original opinions of Hoel & Orvin (1937), Orvin (1934, 1940) and more recently of Dallmann et al. (1993) and Maher et al. (1996). This contentious matter is regarded here as settled, in spite of a partial retreat by Lyberis & Manby (1996), and need not complicate discussions of Paleogene tectonics in the remainder of this work. Strike-slip for hundreds of kilometres, to be energy efficient, requires relatively straight or regular curvature of the fault zone and that it be steeply dipping or near vertical. Once formed such a fundamental fault is a continuing source of weakness. It is therefore not unreasonable to invoke the reverse argument that straight fault zones that persist were probably once strike-slip zones and especially so if shear zones (often mylonitic) have survived denudation and can be observed as in some Svalbard faults. It may be impertinent to suggest that the reason why some structural geologists have been quite sceptical about transpression in Svalbard (whether Paleozoic or Cenozoic) is that whereas the compressive component is always evident, the evidence for a strikeslip component is generally not obvious. The case for strike-slip need not rely on structural evidence; indeed, as indicated above, it depends mainly on an appreciation of the whole regional tectonostratigraphic history. Structures have often been explained by tectonic history and not vice v e r s a . Indeed, the strike-slip component in transpression and transtension may not be obvious because the oblique motion is commonly resolved, or partitioned into compressive or extensional structures and strike-slip faulting (e.g. Harland 1971). A Geological Society of London symposium meeting 5-6 March 1997 amply confirmed the general acceptance of these processes.

SVALBARD'S GEOLOGICAL FRAME

(a)

AGE Q

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Fig. 3.10. (a) Simplified stratigraphy and geological evolution of Svalbard, reproduced with permission from Harland (in press), Svalbard in Encyclopedia of World Regional Geology. Formation names are in lower case, Group names are in upper case. Tectonic episodes in upper case italics. Numbers (not boxed) are thicknesses in km. AV, acid volcanics; BV, basic volcanics.

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Figure 3.11(a-h) reproduces the eight sketch maps published (1966) in a journal that hardly survived the second issue and so is not generally available (although in outline in Nature Harland 1967a). It gives an indication of early thinking along these lines. This was at a time when the major change in many minds was to recognize Mesozoic-Cenozoic continental drift (e.g. for the formation of the Atlantic Ocean). At the first Geology of the Arctic symposium held in Calgary in 1960, ocean spreading was already nascent (e.g. Heezen & Ewing 1961) even though the mid-ocean ridges were not thought by those protagonists to favour the concept of continental drift. But the debate was on (e.g. Harland 1961); but not concluded till the body of earlier opponents were converted

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0.1 I= . ~ ~ r 7.5 A, 0.5A. V var Alkhorn Lst -I A o . u / ~Dunderdalen Lovliebr. BV I ST JONS- Z ~ =Chamberlin. "~ 0,5 Moefjellet DstI FJORDEN ~ = ,~eHegga,, .~ Trondheimfja A B o g e g g1 - -. . . .I. ~. /// ~0~ Fl~yKalvenZ~=vimsodden' ~v "u-' Hansvika 0 . 5 ~ / ......

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STRATIGRAPHY OF SVALBARD by W.B. Harland drawn by P.A.D & C.S. Cambridge Arctic Shelf Programme Key (see also caption} * Biostratlgraphlc a g e of older rocks A. LateVarangertillites A EarlyVarangertillites @ Isotopic a g e in Ma Estimated biostratigraphic age, Mc I l l l Gap in stratal record

I g r a b e n deposlts

i. i.i. . ~\ BUCHANANISEN

Pg 2

p

SCHEMATIC (SIMPLIFIED)

{offshore Neogene)

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39

Im

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I I

I I"~' I s. I TER.

(e.g. Bullard et al. 1965). The palinspastic sequence in Fig. 3.11 amplified that of Harland (1965) and may have been the first modelling of continental drift in pre-Mesozoic time. Plate tectonics evolving as the concept for continental drift perhaps too long focused on Mesozoic and Cenozoic ocean spreading so it took some time for Palaeozoic plate motions and their related terrane contrasts and palaeo-oceans to be generally considered. Modifications, of course, were necessary as with the Iapetus Ocean in the Arctic (Harland & Gayer 1972, 1973) and the two and then three province concept (Harland 1975). These ideas were applied by some (e.g. Ziegler 1988), but they were mostly ignored or opposed but have remained with little challenge to the evidence.

40

CHAPTER 3

(b)

Fig. 3.10. (b) Schematic map of Svalbard to illustrate the hypothesis, referred to in this work, of Svalbard as a composite terrane derived from three or four Greenland provinces. Acronyms refer to fault zones: BBF, Breibogen; BFZ, Billefjorden; KHFZ, Kongsfjorden-Hansbreen; LFZ, Lomfjorden; RFZ, Raudfjorden; VL, Veteranen Line. Early Cretaceous dolerite sills are widespread and indicated on the map as blacked-in islands. Kong Karls Land (not indicated) is Triassic, and Kvitoya (outside the frame to the east of Nordaustlandet) is dominated by Caledonian metamorphic basement.

Late Devonian transport and arrival of Svalbard by Carboniferous time and the accompanying Ellesmerian Orogeny is shown in Fig. 3.1 l(d). Trettin (1991, p. 338) on the origin of the Ellesmerian Orogeny suggested 'Convergence of North America with another plate.., but that plate has not been identified with any assurance .... The convergence may have been orthogonal or oblique, and, in the latter case would have been accompanied by strike-slip, but pure strike slip without a component of convergence could not have caused such extensive deformation.' The Ellesmerian Orogeny was suggested (Harland 1965) to have resulted from the impact of Svalbard arriving by Devonian strike-slip and at the same time rucking up the Lomonosov Ridge by direct compression in its front against an ocean floor.

3.5.3

Polar and lithosphere wander, palaeoclimates

The palaeolatitude and relative longitude of points o f the Earth's crust, as well as their orientation have c h a n g e d t h r o u g h time. To distinguish polar a n d lithosphere w a n d e r i n g depends on having some global reference frame which, while difficult to argue, is not necessary for the p u r p o s e here. It is of especial interest to plot the

progress of Svalbard, and indeed its constituent parts, with respect to the N o r t h Pole at least t h r o u g h P h a n e r o z o i c time. F o r this purpose the figure by H a r l a n d , P i c k t o n & Wright (1976) has been r e d r a w n in Figure 3.12. It shows the progress of Svalbard n o r t h w a r d s t h r o u g h Silurian to Pleistocene time with palaeolatitudes changing from 10~ to 76~ The points for a curve show sudden shifts n o r t h w a r d of a b o u t 15 ~ near the S i l u r i a n - D e v o n i a n b o u n d a r y and a b o u t 20 ~ in Late Triassic time. This means only that there was a general shift related to g r o w t h and disintegration of Pangea. M o r e should not be read into it because the points were obtained often indirectly f r o m successive palinspastic maps. They say little a b o u t the m o t i o n s relative to n e i g h b o u r i n g lithosphere. The curve could be extended b a c k w a r d s to a near-equatorial position for V e n d i a n and C a m b r i a n time which simply makes the average n o r t h w a r d w a n d e r of say 75 ~ t h r o u g h say 500-600 million years. The evidence for Svalbard in tropical latitudes, say 500-600 Ma ago, was early suggested by sedimentological indicators in the whole Greenland, Svalbard, Scandinavian region (e.g. Bain 1960). Palaeomagnetic evidence for near equatorial latitudes, was first put forward for Greenland and Norway to support a low latitude in spite of extensive Early Vendian glacial

SVALBARD'S GEOLOGICAL FRAME

41

Cambrian and early Ordovician (500-470 Ma). The situation depicted here had probably already existed for some hundreds of millions of years, because in the dashed areas sediments commonly up to 20 km thick accumulated and only the uppermost beds are Cambrian and Ordovician. This is commonly known as the Caledonian geosyncline. Immediately preceding mountain belts are shown by vertical shading, with ancient continental areas blank.

Late Ordovician to Silurian (470- 400 Ma). Caledonian movements deformed the sedimentary and volcanic rocks of the geosyncline, with accompanying metamorphism and plutonism, to form the mountain belt shown here.

Mid-Devonian (c. 360 Ma). In the north by Devonian time the main compression was complete. Some plutonism continued, while uplift resulted in erosion, and deposition of the Old Red Sandstone in intermontane troughs (fine horizontal lines) which are related to fault zones (bold dashed lines) along which horizontal movements later occurred. In the Appalachian area widespread and intense deformation, metamorphism and igneous activity took place (the Acadian Orogeny).

Late Devonian to early Carboniferous (c. 350 Ma). At a a time not clearly defined, a series of parallel horizontal (transcurrent) fault movements took place. These have been demonstrated in Scotland, have been claimed in Newfoundland and are postulated in and near Spitsbergen. They all had the same sinistral (anti-clockwise) sense of movement, resulting in eastern Newfoundland, Europe and Spitsbergen moving north with respect to America and Greenland. There was probably also some sinistral rotation along this belt. From palaeomagneticevidence, Newfoundland turned through 30 ~ about this time (Black 1964), and the author tentatively suggests a similar rotation of Breggerhalveya (a smaller mass) in Spitsbergen. In addition to strike-slip movement, some minor compression affected the Spitsbergen area in late Devonian time (the Svalbardian folding). In East Greenland rather more disturbance is evident through Devonian and Carboniferous time. The Franklinian geosyncline of the Canadian Arctic was deformed in late Devonian and/or early Carboniferous time to form the Innuitian mountain belt (vertical shading).

.M.~

Fig. 3.11. Sequence of palinspastic reconstructions for the North Atlantic and Arctic from Cambrian to the present-day. Maps and captions are reproduced from Harland (1966) 'A hypothesis of continental drift tested against the history of Greenland and Spitsbergen', in Cambridge Research, 2, pp. 18-22, possibly the last publication of that journal. (a) Cambrian and early Ordovician; (b) Late Ordovician to Silurian; (c) Mid-Devonian; (d) Late Devonian to early Carboniferous; (e) Triassic; (f) Early Tertiary; (g) Mid-Tertiary; (h) present day.

Triassic (c. 210 Ma). The transcurrent faulting depicted in (d) resulted in the above relationships in the Arctic at latest by mid-Carboniferous time (c. 325 Ma). Whereas conditions in the (present) Arctic lands may have remained relatively stable until about 100 Ma (mid-Cretaceous time), a span of nearly 250 million years the Upper Paleozoic geosyncline in the Appalachians and central Europe was compressed in late Carboniferous and Permian time. This area (dashed) had achieved some stability by Triassic time. Thereafter it is possible that the Atlantic separation commenced; marine conditions appear to extend through the Arctic zone of potential separation. Extensive (Late Jurassic) dolerite intrudes earlier rocks in Spitsbergen and Canadian Arctic. The Lomonosov Ridge was still part of the Barents Shelf margin.

Early Tertiary (c. 50 Ma). (1) Cretaceous sediments, the oldest identified (marked K on the map), show the proto-Atlantic was already in existence, at least in the south, before Tertiary time. (2) The Brito-Arctic igneous province was active from end-Cretaceous to Early Tertiary time in the present continental margins (crosses). (3) Palaeomagnetic evidence suggests that Greenland moved away from North America (Labrador) in post-Triassic time. (4) Lower Tertiary rocks are folded in the intense orogenic belt of western Spitsbergen, probably in northeast Greenland, and also in the Canadian Arctic Islands (ornamented). This compression resulted from the northward movement of Greenland. (5) Continued northward movement of Greenland further separated the volcanic provinces of the British Isles and East Greenland and also of Disko and Baffin Islands. Sinistral movement on the Wegener Fault between Ellesmere Island and northwest Greenland and dextral movement now inferred in west Spitsbergen, separated Spitsbergen from northeast Greenland along the De Geer line (bold lines). (6) The resultant separation between Spitsbergen and Ellesmere Island accompanied a separation of the Lomonosov Ridge from the Barents Shelf by the formation of new Arctic ocean along a mid-Arctic zone of growth. (7) All of the above movements were accompanied by the growth of new ocean floor (shaded) along the mid-oceanic zones (small dashed lines); older oceanic crust is present in the North Candian Arctic Basin (stipple).

Mid-Tertiary (c. 3 0 - 2 5 Ma). The situation depicted in (f) of a separation of continental masses by the formation of new ocean floor (added along the mid-oceanic zone) continued throughout Tertiary time. Activity continued within the Brito-Arctic volcanic province with the growth of Iceland, Jan Mayen and Faeroe Islands.

.M,~ Fig. 3.11. (continued).

Present configuration of the continents and oceans. The North Canadian (Arctic) basin is the oldest, with the The North Eurasian and Atlantic basins being late Mesozoic to Cenozoic age. The short dashed lines indicate zones of present volcanic and seismic activity, i.e. active spreading zones.

SVALBARD'S GEOLOGICAL FRAME deposits (Harland & Bidgood 1959; Bidgood & Harland 1961; Harland 1964). Later palinspastic continental reconstructions supported this position (e.g. Smith, Hurley & Briden 1980). However, Smith (in press) suggests higher latitudes notwithstanding related halite indicators.

43

detail in Chapter 19 (Section 19.6.3). Jurassic temperatures were recorded as somewhat higher (16-10 ~) than Cretaceous (10-6~ The Early Cretaceous marine temperatures could be compatible with the evidence of the later glacial dropstones of Aptian-Albian becoming more abundant in Paleocene strata (Pickton 1981).

The climatic implications are significant for sedimentation in Svalbard. Harland, Pickton & Wright used the data to illustrate the latitudes of coal formations in Svalbard, from Late Devonian through late Eocene-Oligocene occurrences with at least ten intermediate stages with coal swamps, whenever other environmental factors were appropriate. Steel & Worsley (1984) and Worsley in Aga et al. (1986, pp. 22-23) adapted this same curve to explain other aspects in the sequence of sedimentation such as Bashkirian to Artinskian sabkha environments, at e. 30~ and high organic silica production at c. 40~ The only significant carbonate production in a clastic dominated sequence was in 'later Carboniferous and early Permian time' 'when Svalbard may have lain in the northern arid climatic belt'.

Pchelina (pp. 60-66 in Krasil'shchikov 1996) abstracted unpublished reports on Mesozoic Svalbard. She postulated four sedimentary cycles. (1) Early and Mid-Triassic time when the climate was hot and sufficiently arid so that vegetation cover played an insignificant part in the source area. Deposition took place in warm shelf seas. In postDevonian time high salinity of basin water decreased and transgression peaked in Anisian time with phosphate formation. Late Ladinian uplift took place. (2) Late Triassic and Early-Mid-Jurassic time when hot but intermittently humid climate prevailed. Carnian humid but cooler climate and lagoonal coal accumulation prevailed. (3) Late Jurassic to Berriasia~Barremian time with a humid but cooler climate and coal accumulation. (4) Aptian and Albian stages witnessed cool humid conditions accompanied by extensive transgression.

Renewed palinspastic map sequences by the Chicago group were plotted on a north polar projection (Rowley & Lottes 1988). These figured reconstructions at intervals, only from initial Cretaceous time, show latitudes for mid-Spitsbergen at 75~ rising to 76~ Paleogene time up to 78~ in Neogene time. A longer map series beginning at initial Triassic time by Smith et al. 1994 on a Molleveide equatorial projection has Spitsbergen in a marginal position and not so precisely located. Moreover, throughout Mesozoic time Svalbard was depicted there as separated from North Greenland. By adjusting Svalbard to a more likely position its latitudes (from 31 stage maps) show a rapid northward movement from 45 ~ to 60~ in Triassic time, Jurassic latitudes change from 60~ to 66~ Early Cretaceous 67 ~ to 70~ and Neogene to maximum at 80 and then back to about 78~ as at present.

3.5.4

Differential vertical lithosphere motions

Thickness of strata generally measures subsidence, especially when shallow water facies prevail at least at the beginning and end of the sequence. In a marine succession accumulating during many millions of years, the eustatic changes are probably reflected by changes in facies or gaps in the succession and so may be averaged out. Only by comparing successive isopach maps can the overall pattern of the subsidence be assessed. However, allowing that basins develop in contrast to neighbouring zero subsidence, it is meaningful to compare maximum or typical thickness for comparison through time. These are plotted on a linear time scale in Fig. 3.13 as was first attempted with much less data (Harland 1961). Evidence of deformation for tectonic activity is also indicated, but the older rocks need at least three separate columns for the different terranes and only some better known ones are selected here. It has been argued that at least two components in relative sea level change (in addition to eustatic changes) are necessary, namely subsidence due to lithosphere spreading e.g. in pull-apart basins with local cooling contraction and/or due to regional lithosphere contraction through cooling. A preliminary study of these problems concluded that the very long continued subsidence during Hecla Hoek deposition and in the accumulation of later platform sediments required regional lithospheric cooling. Similarly subsequent differential Late Cretaceous uplift required a thermal expansion mechanism in the mantle (Harland 1969). Figure 3.13 illustrates the contrast in a diagram from which precise quantitative conclusions are not permissible. However, three contrasting orders of magnitude are evident. The long narrow

Direct palaeomagnetic studies of Svalbard rocks (Harland 1959) have generally yielded disappointing results. An extensive sampling of pre-Devonian strata in 1958 seemed to be unrewarding because of later tectonism. Devonian strata were unstable and methods of washing were not then sufficient when Greenland and Norway indicated low latitudes in Vendian-Cambrian time. Watts (1985) investigated Early Carboniferous sandstones. Briden et al. (1988), without Svalbard data, concluded that relative E - W motion between Laurentia and Baltica is not discernible while differences of pre-Carboniferous (N-S) strike slip of more than 1000 km may be entertained but 'later strike-slip on this scale is no longer considered likely'. Watts's conclusions from Early Carboniferous Svalbard data are similar and palaeolatitudes of 14 ~ to 18~ were suggested. Other palaeomagnetic studies have been reported (e.g. Storetvedt 1972; Sandal & Halvorsen 1973; Levlie et al. 1984; Torsvik, Lovlie & Sturt 1985; Jelenska 1987, 1988-1989; Jelenska & Zawandowski 1986; Jelenska & Vincenz 1986). The palaeoclimatic implications of these palaeolatitudes are discussed in some of the historical chapters. Positive palaeotemperature determinations of sea water from stable oxygen and carbon isotopes (180 & ~3C) gave the results for Jurassic and Cretaceous fossils (Ditchfield 1996 et seq.). They are listed in some

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44

CHAPTER 3 CENTRAL BASIN

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vertical strips as in the p r e - D e v o n i a n Eastern terranes and in the Central Basin succession indicate slow subsidence averaging 25 m per million years (c. 0.025 m m a - l ) . This represents the consequence o f long c o n t i n u e d m a n t l e cooling in a stable tectonic environment. The m o r e rapid subsidence, at least 10 times that rate characterises a tectonically m o r e mobile e n v i r o n m e n t possibly with pull-apart basin subsidence. The extreme subsidence evident in the F o r l a n d s u n d e t G r a b e n is a syntectonic p h e n o m e n o n . Uplift is n o t so easy to m o n i t o r , but there is a parallel contrast between, for example, the slow tilting up to the n o r t h in Late Cretaceous time leading to an u n c o n f o r m i t y truncating Albian strata at an angle o f less t h a n 1~ within a time span of perhaps 35 million years a n d the orogenic uplift in a m u c h shorter time interval r e m o v i n g m a n y kilometres o f strata. The former was the result of m a n t l e heating in anticipation o f the thermal break up of L a u r e n t i a and caused Svalbard to rise above sea level at the N W corner of the Barents shelf exposing the strata that continue b e n e a t h the Barents sea.

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Fig. 3.13. Plot of subsidence against time for western, central and eastern areas. The linear time-scale is taken from Fig. 3.7 and is extrapolated. Three pre-Carboniferous terrane and two post Devonian terrane successions are selected and depicted diagrammatically. One square indicates approximate net subsidence of 250 m as measured by stratal thickness and the side of the sequence represents 10 million years. It does not indicate sediment volume. Because shallow water facies recur at intervals average sediment thickness thus represents net subsidence with respect to sea level. The diagram shows differences of an order of magnitude in subsidence rates. Lesser discrimination is not significant because of uncertainties in the time scale, age of sediments and the rough selection and plotting of thickness. A continuous vertical line implies one succession, sketched for this work.

PART 2 Regional descriptions Chapter Chapter Chapter Chapter

4 5 6 7

The Central Basin, 47 Eastern Svalbard platform, 75 Northern Nordaustlandet, 96 Northeastern Spitsbergen, 110

Chapter Chapter Chapter Chapter

8 9 10 11

Northwestern Spitsbergen, 132 Central western Spitsbergen, 155 Southwestern and southern Spitsbergen, 179 Southern Svalbard: Bjornoya and submarine geology, 209

Camp in snow on the southwestern flank of the icefield Lomonsonfjonna. In the distance the glacier Wilsonbreen flows down between Backlundtoppen on the right and Gotitsynfjellet on the left. The cliffs are mainly of late Neoproterozoic carbonates and tillites. Lomonsovfonna is a large snowfield in central Ny Friesland providing access by sledge down the many valley glaciers which it feeds. Photo M. J. Hambrey CSE 1981. (SP. 985a).

View from the icefield Lomonsovfonna, looking north to the high mountains of Ny Friesland from which the glaciers flow westward down to Wijdef]orden. The cliffs expose Proterozoic metamorphic Caledonian basement. Many mountains carry a snow cap resting on an uplifted and exhumed dissected preCarboniferous peneplane. The lone sledger (his companion being the photographer) demonstrates transport on a light-weight, sortie from a main camp. Photo M. J. Hambrey, CSE 1982 (SP 1257).

Typical view in the middle reaches of the glacier, Tryggvebreen, showing present-day transport by (Bombadier) snow scooters. The cliffs are of 'lower Hecla Hock' (Stubendorffbreen Supergroup) Proterozoic Caledonian basement. Snow scooters now provide basic transport, especially in the winter and spring months. In summer they are limited to high snow fields and the upper reaches of the glaciers they feed. Photo M. J. Hambrey, CSE 1982 (SP. 1351).

Cliffs of Akademikerbree dolostone/limestone, at Draken in Olav V Land (SE of Ny Friesland). The eight-wheel, tracked, amphibious vehicle is hauling a train of sledges over hard snow and ice; but it travels not so well in deep snow. It was mainly used for crossing marine mud flats from a supply boat, travelling up braided streams or across rotten bay ice. Routine man-hauling also favoured a train of sledges especially across uneven ground to spread the impact of obstacles. Four men would routinely haul two lightly laden 12 foot Nansen sledges and a pulka, divisible into two independent two-man parties. Photo M. J. Hambrey, CSE 1981 (SP10.70).

Chapter 4 The Central Basin W. B R I A N SIMON

R. A. K E L L Y ,

HARLAND ISOBEL

4.1 4.1.1 4.1.2 4.1.3 4.2 4.2.1 4.2.2 4.2.3 4.2.4 4.3 4.3.1 4.3.2 4.3.3 4.3.4 4.3.5 4.3.6 4.3.7 4.3.8 4.3.9 4.3.10 4.3.11 4.4

Geological frame, 47 Stratal succession, 47 Structural setting, 48 Geomorphology, 48 Van Mijenfjorden Group (Paleogene), 48 History of research, 50 Sedimentary-tectonic interplay, 50 Succession of the main outcrop, 51 Isolated outliers, 52 Adventdalen Group (Cretaceous-Jurassic) (S.R.A.K.), 52 Lithic units, 52 Eastern Nordenski61d Land and southwestern Sabine Land, 53 Sabine Land, 53 Heer Land, 55 Eastern Torell Land, 55 Sorkapp Land, 55 Wedel Jarlsberg Land and western Torell Land, 57 Western Nathorst Land, 57 Western Nordenski61d Land, 58 Central Nordenski61d Land, 58 Oscar II Land, 59 The Kapp Toseana and Sassendalen Groups (Liassic, mainly Triassic) (W.B.H. & I.G), 59 4.4.1 Lithic scheme for Kapp Toscana and Sassendalen groups in the Central Basin, 59

Svalbard rocks conveniently divide into younger and older rocks at about the initial 'Carboniferous' boundary. There are, however, latest Devonian strata in places continuous with Carboniferous sedimentation. The older rocks are tectonically as well as stratigraphically complex. Beginning with the sub-Carboniferous (peneplane) unconformity resting variously on Devonian and preDevonian strata, it expressly excludes any older rocks. The term basin as in Central Basin applied here is used in a structural sense for what amounts to a broad brachysyncline. The accumulated strata were also formed in sedimentary basins with shifting depocentres. The most obvious is the Paleogene sedimentary and structural basin commonly referred to as the Tertiary Basin. The Central Basin excludes the western and southwestern areas (Chapters 9 and 10) where older and younger rocks are caught up in the Paleogene West Spitsbergen Orogeny. It also excludes the areas, mainly in the islands in the east, where subsidence was less marked at first and tectonic platform conditions prevailed. The younger succession, Tournaisian through Paleogene (a span of about 330million years) has suffered only minor diastrophism in contrast to earlier events. Central Basin thus refers to the whole post Devonian cover or platform sequence in this study area. Most mineral prospects of economic interest in Svalbard belong to these younger rocks, from the many coal deposits of which Early Carboniferous and especially Early Paleogene horizons have been exploited. Furthermore, in the search for petroleum, source rocks of Late Carboniferous-Early Permian, Early to Mid-Triassic and Jurassic age have been identified and Late Permian, Late Triassic to Early Jurassic reservoir rocks. Official geological maps were available on three principal scales covering the Central Basin as follows: 1:1 M Series: Bedrock Map of Svalbard and Jan Mayen. Winsnes 1988. Sheet (Temakart No. 3). 1:500000 Series: Sheet 1 G. Spitsbergen, southern part. W. K. Dallmann (1993). 1 : 100 000 Series: Sheets B.7.G. Trekroner B.8.G. St Jonsfjorden. Bergh et al. (1993)

with contributions with

GEDDES

& PAUL

A. D O U B L E D A Y

4.4.2 Sassendalen to Storfjorden (southern Sabine Land), 61 4.4.3 Nordfjorden (S Dickson Land and E Oscar II Land), 62 4.4.4 Western Isfjorden (SW Oscar II Land and NW Nordenski61d Land), 62 4.4.5 Van Keulenfjorden (W Nathorst Land and N Wedel Jarlsberg Land), 62 4.4.6 Wedel Jarisberg Land, mid and southeast, 62 4.4.7 Sorkapp Land, 63 4.4.8 Kongsfjorden, 63 Biinsow Land Supergroup (Permian-Devonian) 4.5 (W.B.H, I.G. & P.A.D.), 63 Tempelfjorden Group (Permian) 4.6 (W.B.H, I.G. & P.A.D.), 63 4.6.1 Kapp Starostin Formation, 63 4.7 Gipsdalen Group (Carboniferous) (W.B.H, I.G. & P.A.D.), 66 4.7.1 Gipshuken Formation (Dickson Land Subgroup), 66 4.7.2 Wordiekammen Formation (Dickson Land Subgroup), 68 4.7.3 Minkinfjellet Formation (Campbellryggen Subgroup), 70 4.7.4 Ebbadalen Formation (Campbellryggen Subgroup), 70 4.7.5 Hultberget Formation (Campbellryggen Subgroup), 71 Billefjorden Group (Early Carboniferous), 71 4.8 4.8.1 Mumien Formation, 72 4.8.2 Horbyebreen Formation, 72 4.9 Structure and development of the Central Basin, 73

B 9.G. B 10.G. B.11.G. B.12.G. C.7.G. C.8.G. C.9.G. C.10.G. C.11.G. C.12.G. C.13.G.

Isfjorden, Ohta et al. (1991) Van Mijenfjorden, Hjelle et al. (1986) Van Keulenfjorden, Dallmann et al. (1990) Torellbreen, Ohta & Dallmann (1992+updated 1996) Dicksonfjorden, Dallmann et al. (1994) Billefjorden, Lauritzen et al. (1989) Adventdalen, Major et al. (1992) Breganzav~tgen, Salvigsen & Winsnes (1989) Kvalvagen, Dallmann (1991) Markhambreen, Birkenmajer et al. (1992) Sorkapp, Winsnes et al. (1993), description Dallmann et al. (1993) D.7.G. (not yet published) D.8.G. Negribreen, Miloslavskiy et al. (1992) D.9.G. Agardhfjellet, Miloslavskiy et al. (1993) Titles of map sheets in bold indicate that text accompanies the published map. Some of the titles were provisional at the date listed. 4.1 4.1.1

Geological frame Stratal succession

The Central Basin includes the main development of Carboniferous to Paleogene strata. The somewhat elliptical Central Tertiary Basin provides its southern focus. The succession may be simplified in seven groups (and two supergroups) as follows. Van Mijenfjorden Group, 2.5+ km (Paleogene) mainly continental clastics with some coal and some marine incursions. Nordenski61d Land Supergroup (defined here by the three groups) Adventdalen Group c. 800 m (Early Cretaceous-Jurassic) mainly marine clastics with continental horizons. Kapp Toscana Group, c. 250+ m (Early Jurassic-Late Triassic and latest Permian) mainly continental sandstones with condensed marine deposits.

48

CHAPTER 4

Sassendalen Group, c. 725 m (Mid- and Early Triassic and latest Permian) mainly marine shales. Biinsow Land Supergroup (defined here by the 3 groups:) Tempelfjorden Group, c. 380 + m (Late Permian) mainly marine shales. Gipsdalen Group, c. 850 m (Early Permian and Late Carboniferous and latest Devonian) marine carbonates and evaporites. Billefjorden Group, 316m (Early Carboniferous and latest Devonian) continental sandstones and shales with coals. It so happens that a major hiatus representing at least all of Late Cretaceous time, followed by a distinctive Van Mijenfjorden Group basal conglomerate, makes the Mesozoic-Cenozoic division easy to identify. Similarly a Late Permian hiatus of uncertain span followed by a dramatic change of facies, from Tempelfjorden Group with hard, pale, siliciclastic and chert facies to Sassendalen Group with soft, dark shales, allows an unusually clear division between traditionally Paleozoic and Mesozoic rocks. In each case the break is marked by only slight angular unconformity, but traces of diastrophism can be inferred. Indeed the whole succession has been referred to as an extensive platform sequence in contrast to the pre-Carboniferous strata and structure, but the Central Basin is distinguished from the Eastern Platform, as the names suggest. It is a region of greater subsidence during which the successive depocentres have moved around. Therefore the whole sequence described here and in later chapters in both basin and platform is referred to as the cover sequence. It overlies the mainly Devonian Liefde Bay Supergroup and the pre-Devonian basement. The classic section through much of the cover sequence is the Festningen profile (Festungs Profil) along the south coast of Isfjorden between Kapp Linn6 and Gronfjorden (Fig. 4.1).

4.1.2

Structural setting

As with most regional chapters here the limits are somewhat artificial, for descriptive convenience. The boundary to the north is simply stratigraphical. The 'postDevonian' platform cover is included here and the 'pre-Carboniferous' Old Red Sandstone and basement are excluded. The north of Svalbard was tilted upwards during Mesozoic time which resulted in the exposure of the older rocks to the north and their preservation in the Central Basin. The low dips result in a topographically controlled outcrop pattern. The western limit is complex with at least two boundaries. The later one is the fold and thrust front of the West Spitsbergen Orogen that postdates almost all the cover sequence. Cover strata are deformed within the fold and thrust belt, but to the west, uplift of the horst graben belt has allowed almost entire removal of the cover. However, the pre-orogenic platform sequence clearly extended westwards and there is some evidence of a NNW-SSE lineament affecting some sedimentation during that long interval. Lineaments have been referred to by various authors which may or may not refer to the same features. (i) Harland & Wright (1979) postulated a strike-slip fault boundary (the Central West Fault Zone) between their western and central provinces in preCarboniferous time, later redefined by Harland, Hambrey & Waddams (1993) as the Kongsfjorden-Hansbreen Fault Zone. Other fault zones with a similar early history, notably the Billefjorden Fault Zone continued intermittent dip-slip movement at least through Jurassic time. (ii) Mork and others (e.g. Mork et al. 1982) argued that the Pretender Fault east of Kongsfjorden extended southwards and became a significant sedimentary control in Triassic time. (iii) The southward extension of the Breibogen Fault has been suggested to exercise a similar, if not identical, control. All three fault proposals in this middle area have no direct observational support. The preference here is for continuing a postulated fault based on quite different and earlier evidence rather than inventing a new one for this function only. Without deciding

this question the lineament may be referred to as the Western Spitsbergen Fault Zone. The eastern boundary is less clear. It has been provisionally taken at the Lomfjorden-Agardbukta Fault Zone, which, while not an obvious boundary between allochthonous terranes, nevertheless continued in activity at least through the cover interval. The southern boundary is at the coastline. Even so this may not be entirely arbitrary because the Central Basin seems to close southwards as indicated by some isopachs and the greater thicknesses of less dense strata may have something to do with this particular elevation. One quite essential and unambiguous feature within the Central Basin is the Billefjorden Fault Zone which can be documented both in pre-Carboniferous rocks and in post-Devonian strata when it continued activity intermittently. Thus we have at least three N-S lineaments that traverse the platform. The Western Spitsbergen Fault Zone, the Billefjorden Fault Zone and the Lomfjorden Fault Zone. These played significant roles during different intervals within the cover sequence. In the nomenclature of this work the Spitsbergen Basin as a whole extended (at times) to the Lomfjorden Fault Zone in the east, east of which is the Svalbard Platform. It may be divided by the Western Spitsbergen and Billefjorden fault zones into the Western, Central and Eastern Basins. It is in this area that the Central Basin is named here and almost coincides with the 'Central Tertiary Basin' of many authors. However, this chapter includes the Eastern Basin as far as the Lomfjorden Fault Zone.

4.1.3

Geomorphology

The most obvious feature as seen on a map is the fjord pattern. Isfjorden from a relatively narrow gateway through the West Spitsbergen Orogen opens eastwards into a large branching sea. Similarly Bellsund divides inland into two large fjords and to a lesser extent Hornsund also. These in part reflect the softer Mesozoic strata dipping to sea level in the basin. On the other hand, the relatively consistent summit heights do not suggest that the Basin structures survived peneplanation in later Cenozoic time. De Geer (1909) and others have argued that the minor fault patterns defined the fjords. In so far as they can be identified this relationship is not obvious.

4.2

Van Mijenfjorden Group (Paleogene)

Paleogene strata are found in three main basin areas. (i) A western offshore wedge of sediment thins from the Knipovich ridge and thickens eastward towards the Hornsund Fault Zone. How much of this submarine succession is Paleogene and how much (probably the major part) is Neogene remains uncertain. This linear wedge extends along to the west of the West Spitsbergen Orogen and was most probably supplied by its erosion. (ii) A zone of graben extends just inshore and parallel to the coastline and appears to have formed within the orogen. Naturally enough it has a long and complex history, being best known in the Forlandsundet Graben and further south in the Calypsobyen outcrop south of Bellsund. Zones (i) and (ii) are treated in their regional context in Chapters 9 and 10. (iii) The Central Basin is the principal onshore outcrop of Paleogene strata and is the subject of this section being the uppermost unit of the Basin: the Van Mijenfjorden Group. Indeed it is this Paleogene group that conspicuously defines the brachysynclinal core of the Central Basin. It is bounded on the west by the West Spitsbergen Orogen which is intimately bound up with the sedimentary sequence. The Van Mijenfjorden Group was originally thicker and extended further west than the present outcrop. However there is one outlier to the northwest, the Ny-Alesund coalfield, exposed just under the thrust front of the orogen where it curves round and is

T H E C E N T R A L BASIN

49

CAROLINEFJELLET FORMATION

Das Festungsprofil (after Hoel & Orvin 1937) GRC)NFJORDEN

HELVETIAFJELLEI FORMATION "t3 .m (1)

(3_ O n," (.9 s

RURIKFJELLET FORMATION

0O I-UJ

Elatidesniveau

._1

uJ

Festning',

LI_

cO ARGARDHFJELLET FORMATION Z < .-)

Festningskjoeret~ "4%

!...

:3

(~.~ ~9,~'~~'~'~

~Festningen

- W I L H E L M O Y A FM

DE GEERDALEN FORMATION

~,~~~

9 o~ ~'~6~'~

BOTNEHEIA FORMATION .,.fee C6e's

CO

STICKY KEEP FORMATION

Ostre

,m !,...

\,o,~e'{~ Vestre

( Tvillingodde

VARDEBUKTA FORMATION

C3 O

E 1,...

(D

co

n

KAPP STAROSTIN FM cO .Q L_

/ N -4

i

Kapp Starostin( 0

500

I

I

1000m

GIPSDALEN AND BILLEFJORDEN GROUPS

I

Fig. 4.1. Reproduction of the Festningen profile as figured by Hoel & Orvin (1937), Das Festungsprofil auf Spitzbergen. Karbon-Kreide. Part 1. Vermessungsresultate. Skrifter om Svalbard og Ishavet 18, Plate 4. The current rock unit names have been added.

50

CHAPTER 4

overthrust towards the north or northeast. This curvature, convex to the NE, separates the Ny-Alesund Basin from the main Central Basin. By its location it is treated in Chapter 9 but it is probably an extension of the Central Basin and most authors include the strata within the Van Mijenfjorden Group.

4.2.1

History of research

Because the principal coalfields of Spitsbergen are Paleocene, as exposed in zones (ii) and (iii) above, the rocks have attracted attention from the earliest days and not least because the N-S basin is truncated by E-W fjords where the coal seams may be seen in cliff sections above sea level near the outer rim of the basin. Therefore even the earliest geological accounts refer to coal. Hoel (1920) wrote the first systematic descriptions of coalfields in Svalbard. The age of the deposits was subject to long-continued uncertainty as is discussed in Chapter 20. The plant remains were correlated with similar floras in the British Isles, Greenland and the Canadian Arctic all of which were first thought to be Miocene (e.g. Heer 1866-1880; Nathorst 1910) and then debated as Eocene and only later this century were correlated by marine fossils as Paleocene (Ravn 1922; Vonderbank 1970). The floras were thus eventually accepted as Paleogene rather than Neogene (e.g. Manum 1954-1966; Manum & Throndsen 1978-1986). For many years the succession of the Central Basin followed the early description given by Nathorst (1910). Indeed the same units were described in those terms by Orvin (1940) under the following heads: (6) (5) (4) (3) (2) (1)

Upper Plant-bearing Sandstone Series Flaggy Sandstone Series Upper Black Shale Series Green Sandstone Series Lower Dark Shale Series Lower Light Sandstone Series.

These six divisions formed the basis of the current lithic scheme with new nomenclature as introduced by the Norsk Polarinstitutt in the early 1960s (Major & Nagy 1964, 1965). Major & Nagy 1972 and largely confirmed by the SKS) (Fig. 4.2). Modifications were introduced from work by Russian geologists especially Livshits (1964-1974). The sequence of nomenclature is discussed in Chapter 19 and adopted in Section 4.2.3 below. The minor differences stem from the different facies as developed, for example, in the east and west of the basin. The tectonic setting, and especially the relationship between the long established Central Tertiary Basin and the newly elucidated West Spitsbergen Orogen was shown to be a product of oblique compression between Greenland and the Barents Shelf as they separated along a dextral shear zone (Harland 1965, 1966, 1969) to which the concept of transtension alternating with transpression was introduced (Harland 1971) and applied to the orogen (Lowell 1972). The West Spitsbergen Orogen itself being defined (Harland & Horsfield 1974), and related to the sedimentation (e.g. Kellogg 1975). The latest phase in these investigations has been the application of sedimentological principles to the successions with the publication of detailed logs from which the interplay of sedimentation source, supply and subsidence was related to the tectonic development of the basin. A series of studies indicated a close correlation between these events and the transtensional, then transpressional phases of the dextral shear zone (Steel 1977; Steel et al. 1981; Nottvedt 1985; Steel & Worsley 1984; Steel et al. 1985). Climatic and palaeolatitudinal considerations have been the subject of further studies as summarized (Harland, Pickton & Wright 1976; Worsley in Aga et al. 1986).

4.2.2

The sedimentary-tectonic interplay

The Central Basin and the West Spitsbergen Orogen provide an excellent example of how regional tectonics can throw light on the

Fig. 4.2. Map of the Paleogene outcrops in the Central Basin. Adapted with permission from SKS proposals for Lithostratigraphical Nomenclature o f the Tertiary Rocks of Svalbard (Dallmann et al. 1995) Figure 1. development of a sedimentary basin, and how in turn the facies within the basin can elucidate the related earth movements. The model proposed by Steel and others follows Harland's transtension-transpression model for the West Spitsbergen Orogen with

THE CENTRAL BASIN detailed sedimentological interpretation. Their conclusions are outlined below (Steel, Dalland et al. 1981; Steel & Worsley 1984; Steel, Gjelberg et al. 1985). The Paleogene succession thickens from 1.5 km in the northeast to 2.5 km in the southwest reflecting the greatest thickness where it is truncated by the orogenic sheared margin. A further 1.5 km of sediment may have accumulated on top of the preserved deposits and eroded as indicated by vitrinite reflectance studies. (i) The initial phase represented by the Paleocene Todalen (coal-bearing) Member, of the (lower) Firkanten Formation, was probably formed in a semi-enclosed embayment. Coal seams are abundant throughout the basin, being exposed above sea level at the rim of the basin where the formation rests unconformably on Early Cretaceous strata. (ii) The succeeding phase is one of transgression reflected by the two facies of the interfingering Endalen and Kalthoffberget members of the Firkanten Formation. This phase concludes with the pro-delta-shelf sandstones and siltstones of the Basilika Formation. The transgressive phase is thus marked by a sequence from coaly, through wave-dominated shelf, to pro-delta environments. Tectonically this was interpreted as a transtensional phase, so deepening the basin, with an axis approximating to the shear zone. This deepening reflected excess of subsidence over sedimentation in the absence of a compressive element that would provide an erosive uplifted source. The excess deepening probably exceeded any eustatic rise of sea level. These two phases were well understood from the thorough investigations of the coal-bearing strata, whereas the later story has less detail to support it. (iii) The following phase was clearly regressive (e.g. Kellogg 1975; Steel et al. 1981). The infill of the basin continued to thicken towards the shear zone, but with some sediment arriving from the direction of the shear zone rather than solely from the northeast. This situation is reflected in the shallow marine sequence of the Grumantbyen Formation to the N W and the offshore Basilika Formation to the SW. Sedimentation probably kept pace with slow subsidence as indicated by extensive bioturbation so heralding the latest Paleocene-Eocene orogenic uplift. (iv) The final phase is dominated by the Eocene transpressive regime which is indicated by upward coarsening successions, the marked and exclusive influx of sedimentation from the west and abundant syn-sedimentary deformation. The Gilsonryggen Formation comprises 2 0 0 - 4 0 0 m of black shales and occasional siltstones giving place to the Battfjellet Formation scenario as indicated above and capped by the Aspelintoppen Formation in which occurs the conspicuous liquefaction and soft-sediment deformation that indicates extreme instability in a coastal deltaic plain. Such observations were also noted by unpublished fieldwork in central Nathorst Land in 1974 (Pickton & Wright CSE).

4.2.3

51

Fig. 4.3. Stratigraphic units of the Van Mijenfjorden Group, with nomenclature recommended by SKS. Redrawn from SKS proposals for the Lithostratigraphical Nomenclature of the Tertiary Rocks o f Svalbard (Dallmann et al. 1995). Figure 2a which was revised from Steel et al. (1985). Central Basin units (CB1-6) are used in this work.

The succession of the main outcrops

The stratigraphic succession as recommended by Dallmann et al. (SKS, 1995) is summarized in Fig. 4.3. Van Mijenfjorden Gp (Major & Nagy 1964, 1972) comprises six formations, modified in detail. (6) Aspelintoppen Fm (Major & Nagy), >1000m (CB6). Poorly sorted sandstones, siltstones, calcareous shales, clay ironstones, thin coals and plant beds, altogether exhibiting soft sediment deformation, occur mainly in hill tops in the centre of the Paleogene basin. (5) Battfjellet Fm (Major & Nagy), 60-300 m (CB5). Well-laminated fissile and cross-bedded alternating grey-green to whitish sandstones interbedded with siltstones and minor black shales, some with marine bivalves. (4) Frysjaodden Fm (Livshits 1967), 200-400m (CB4a). This formation between CB5 the Battfjellet (sandstone) Formation and (CB3) the Grumantbyen (sandstone) Fm exhibits different successions between the NE and SW developments which has caused some confusion between Russian workers in the west and Norwegian in the east. The complex interdigitation of the strata reflects a changing pattern of sedimentation and provenance and the nomenclature has been resolved accordingly by SKS (1995) as follows.

In the NE the original Gilsonryggen Fm (of Major & Nagy 1964) is typically a black silty-shale succession with some chert pebbles and marine bivalves and it should be referred to as the Frysjaodden Fm (SKS 1995). In the SE the Hollendardalen (sandstone) Fm (Livshits 1967), (CB4), is a wedge of sandstone thickening to the SW and dividing the lower part of the Frysjaodden Fm. It was given formation rank because of the history of its name and its significance as indicating the first major sedimentation source in the west. A new name, Marstranderbreen Mbr (SKS 1995), was proposed for the shales of the Frysjaodden Fm beneath the Hollendardalen Fro. The shales above it being referred to as the Gilsonryggen Mbr up to another sandstone wedge from the west: the Bjornsonfjellet Mbr (Steel et al. 1981). The shale between this member and the Battfjellet Fm has no separate name and is presumably a digitation of the Gilsonryggen Mbr. The Sarkofagen Fm (Major & Nagy 1972) corresponding to part of the Hollenderdalen and probably the Morstanderbreen units is relegated to disuse. Hollendardalen Mbr, in the lower part which corresponds to the upper part of the green sandstone of the earlier Sarkofagen Fm. (3) Grumantbyen Fm (Livshits 1964), 200 45 m (CB3). Replaces the lower part of the earlier Sarkofagen Fm as defined further east (Major & Nagy 1964). It is a greenish (glauconitic) bioturbated sandstone.

52

CHAPTER 4

(2) Basilika Fm (Major & Nagy 1964, 1972), 10-350m (CB2). Mainly black and dark grey shales with occasional well-rounded pebbles of quartzite and chert and interbedded siltstones and sandstones near the base. (1) Firkanten Fin (Major & Nagy 1964), 100-170m. A coal-bearing sandstone unit interbedded with marine and non-marine siltstones and shales with a basal conglomerate resting with sub-parallel unconformity on Carolinefjellet Formation members. It has been divided into four members. Endalen Mbr (Steel et al. 1981, SKS), 40-100m (CBI.d) of stacked 4-5m bioturbated sandstone, cliff-forming strata with interbedded thin conglomerates, clay ironstones and minor shales, interfinger with underlying member. Kolthoffberget Mbr (Steel et al., SKS), up to 120 m (CBI.c) is a fine-grained lateral equivalent of the above member comprising organic-rich shales and fine bioturbated sandstones. Todalen Mbr (Steel et al., SKS), 60 m comprises three to five sequences of shale-siltstone-sandstone-coal. Gronfjorden Mbr (SKS), 4.5m is the irregular basal conglomerate with conglomeratic sandstones.

4.2.4

Isolated outliers

Southwest Sorkapp Land Oyrlandet Formation.

This is a poorly exposed sandstone, with some fault contacts, occurring at the southwestern tip of Sorkapp Land. It was regarded by Atkinson as part of the Central Basin succession and was correlated by Livshits (1992) with the Firkanten Formation and so mapped by SKS (fig. l a) and therefore part of the Van Mijenfjorden Group. The above name may be useful unless or until it is established as Firkanten Formation. It occurs well to the west of the main foldbelt which normally defines the western margin of the main Paleogene outcrop, yet it is still within the orogenic zone.

Eastern Outliers.

Whereas the Van Mijenfjorden Group main outcrop is bounded in the west north of Sorkapp Land by the eastern margin of the orogenic fold and thrust belt so forming a sharp, often vertical, limb to the Central Basin, its eastern boundary merges eastwards into the relatively flatlying platform mainly of Mesozoic strata. Consequently the Paleogene strata pass eastwards from the main outcrop into many outliers in the tops of the higher mountains and there is no knowing how far the Paleogene strata extended.

The Ny-,~lesund coalfield.

The outlier of undoubted Paleocene strata (Chapter 9) probably correlates with the one or two of its lower formations. Its Ny-Alesund Subgroup is classed within the Van Mijenfjorden Group of the Central Basin (SKS).

4.3

The Adventdalen Group ( C r e t a c e o u s - J u r a s s i c )

The Adventdalen Group of the Central Basin of Spitsbergen is up to 1800 m thick. Early, Mid- and Late Jurassic, and Early Cretaceous deposits are present. It rests on the Kapp Toscana Group with varying degrees of minor unconformity. In contrast the overlying Firkanten Formation of the Van Mijenfjorden Group, of Paleogene age, rests with increasing unconformity northwards on different members of the Carolinefjellet Formation; parts of the Mid-Albian and the whole of the Late Albian and Late Cretaceous deposits are missing (Nagy 1970). The Adventdalen Group forms a NNW-SSE-striking asymmetric syncline, which plunges gently to the SSE. Dips in the eastern outcrops are at a low angle and in the western outcrops are variable to steep. The main outcrop lies south of Isfjorden,

Sassendalen and Agardhdalen and runs south to Sorkapp Land, with outliers between Agardhbukta and Wichebukta. For convenience the minor outcrops on the north side of Isfjorden, southern Oscar II Land, are also included here.

4.3.1

Lithic units

Jurassic and Cretaceous strata of Svalbard are treated as a whole in Chapter 19. The following outlines the lithic units of the Adventdalen Group of the Central Basin which for this chapter is extended to the west and south to the outcrop limits.

Adventdalen Gp: Bathonian-Mid-Albian (Parker 1967). Carolinefjellet Fm, 1200+m marine shales to sandstones; Aptian to Albian (Parker 1967). Schiinrockfjellet Mbr, 70+ m, sandstones with minor shales and siltstones; Middle Albian (Nagy 1970). Zillerberget Mbr, 375+ m (Nagy 1970), shales and siltstones often with clayironstones and with minor sandstones; Early to Mid-Albian. Langstakken Mbr, 208m (Parker 1967), sandstones with minor siltstones and shales; Early Albian. Innkjegla Mbr (Parker 1967), 430 m mainly shales and siltstones in the upper part with shales and clay-ironstones in the lower part; Aptian-Early Albian. Dalkjegla Mbr (Parker 1967), 131 m laminated to thin bedded sandstones with alternating shales and siltstones; Aptian. HelvetiafjeHet Fm (Parker 1967), 53 m continental sandstones with coals and minor shales; erosive base; Barremian. Glitrefjellet Mbr, 69 m cross-bedded and rippled sandstones, carbonaceous shales, clay-ironstones and thin coals; Barremian (Parker 1967). Festningen Mbr, 30 m massive sandstones, often conglomeratic, with minor shales; Barremian (Parker 1967). Janusfjellet Subgroup, (Parker 1967): marine, predominantly argillaceous; ?Bajocian-Barremian Rurikfjellet Fm (Parker 1967), 176m shales to siltstones; BerriasianBarremian. Ullaberget Mbr (Rozycki 1959), sandy shales and siltstones with clayironstones and local calcareous sandstone; Valanginian?-Hauterivian. Wimanfjellet Mbr (Dypvik et al. 1991), silty shales with sideritic and calcareous concretions; Berriasian-Barremian. At the base in eastern Nordenskioid Land is the Myklegardfjellet Bed (Birkenmajer 1980), a glauconitic plastic clay with erosive base; Berriasian. Disturbed sedimentation has been related to the effects of an impact (Chapter 19.5.2) At the base in western Torell Land is the Polakkfjellet Bed (Birkenmajer 1975), conglomeratic sandstone; Volgian. Agardhfjellet Fm (Parker 1967), 243 m at type locality to 115m to west but > 49 m locally sandy-conglomeratic base. Revidalen, (Lindstromdalen), thickening but otherwise mainly shales to siltstones and fine sandstones; Bathonian Volgian. Slottsmoya Mbr (Dypvik et al. 1991), grey organic-rich shales with dolostone concretions; Kimmeridgian-Volgian. Oppdalshta Mbr (Dypvik et al. 1991), silts to fine sandstones; Oxfordian. Lardyfjellet Mbr (Dypvik et al. 1991), grey organic-rich shales with dolostone concretions; Bathonian-Callovian. Oppdalen Mbr (Dypvik et al. 1991). This basal unit of the Agardhfjellet Fm is generally calcareous and contains coarse clastics with conglomerates, sandstones, and siltstones, and locally phosphoritic and glauconitic, oolites; Bathonian-Callovian. It includes three beds. Dronbreen Bed (Dypvik et al. 1991), fine sands to silts; BathonianCallovian; Marhogda Bed (B/ickstr6m & Nagy 1985), with a maximum thickness of 1.5 m at the type locality near Diabasodden, south of Sassenfjorden. It is a microsparitic limestone, partially dolomitised and seriticized with quartz grains, chert ooids and glauconite. Brentskardhaugen Bed (Parker 1967), is at the very base of the member, with type locality on the south side of Sassendalen. It contains rounded fossiliferous phosphoritic, chert and quartz pebbles in a microsparitic ferruginous dolomitic cement. It reaches a maximum thickness of 1.35m east of Konusdalen, just west of Marhogda (B/ickstr6m & Nagy 1985). The base is erosional but without angular discordance on the Wilhelmoya Fm. The age is Bathonian. The nodules contain a diverse assemblage of bivalves, ammonites, belemnites and vertebrate bones of Toarcian-Aalenian age (B/ickstr6m & Nagy 1985). The erosive base.rests on the Kapp Toscana Group, whose youngest age is Toarcian (see below, 4.4).

THE CENTRAL BASIN The above units are described briefly from eastern Nordenski61d Land through the main outcrop clockwise along the east coast, where the sequence is only mildly deformed, south to Sorkapp Land, and then northwards through more disturbed strata of the western outcrops within, and in the vicinity of, the western deformation zone.

4.3.2

Eastern Nordenski61d Land and southwestern Sabine Land

In eastern Nordenski61d Land, the Adventdalen region and the mountains to its east, including Helvetiafjellet and Janusfjellet, are characterized by subhorizontal strata, with gentle westerly inclination. The original mapping by Major & Nagy (1964) of the area has been substantially revised and reinterpreted (Sheet C9G, Major et al. 1992). The readily weathered Janusfjellet Subgroup occupies the lower gound with a more intact outcrop pattern and the higher ground is characterized by the Helvetiafjellet Formation with Carolinefjellet Formation above, frequently isolated as outliers (Fig. 4.4). Cliff-forming sandstones crop out clearly in the Festningen Member of the lower part of the Helvetiafjellet Formation, and less prominently in the Sch6nrockfjellet, Langstakken and Dalkjegla members of the Carolinefjellet Formation. This pattern of outcrop continues southeastwards through Lardyfjellet in southwest Sabine Land to Rurikfjellet and Kapp Dufferin in northern Heer Land. The higher members of the Carolinefjellet Formation are progressively cut out northwards under the base of the Paleogene Firkanten Formation, which rests on the Langstakken and Zillerberget members; the latter is only represented in the very southeast of Nordenski61d Land. Thrusting from the west penetrates the Adventdalen Group, particularly at Arktowskyfjellet and Juvdalskampen where it affects the shales of the Agardfjellet Formation. The continuation of the Billefjorden and Lomforden lineaments affect especially the Janusfjellet Formation, causing thinning of sediment, and giving anomalous NNW-SSE striking anticlinal axes running under Bergmannhatten and just to the east of Tronfjellet. East of the Billefjorden lineament, the Agardhfjellet Formation is locally absent. Parker (1967) interpreted this as erosional, but it is at least in part due to decollment/thrusting (Parker 1966; Andresen, Haremo & Bergh 1988; Andresen e t al. 1992). A dolerite sill complex penetrates Triassic sediments around Diabasodden.

Carolinefjellet Fm at Langstakken, the type locality, is 768.5m (Nagy 1975), only the Dalkjegla, Innkjegla and part of the Langstakken members are represented and share the same type locality. Immediately under the Firkanten Formation is the: Langstakken Mbr, 208 m with eroded top; Dalkjegla Mbr, 131 m; Innkjegla Mbr, 429.5 m. Heivetiafjellet Fro. At Helvetiafjellet 54m of non-marine sediments (Parker 1967) comprise: Glitrefjellet Mbr, 49m sandstones to shales, thickening to 66m at Carolinefjellet; Festningen Mbr, 4m massive coarse grained to conglomeratic sandstones. Thickens to 14m on Carolinefjellet. Janusfjellet Subgp. The type section on Janusfjellet, 502 m comprises principally shales and siltstones (Parker 1967). It is marine throughout: Rurikfjellet Fro, 342m at Wimanfjellet is mainly argillaceous; contains two members: Ullaberget Mbr, sandstones with shales are thickest and more sandy in the northwest at Janusfjellet, 160m and generally thin to the south west, e.g. Lardyfjellet, 60m although are even thinnner in association with the Billefjorden and Lomfjorden faults (Dypvik et al. 1991). Between one and five coarsening upwards cycles are recognized. Bioturbation is characteristic, with some ammonites and belemnites; bivalves include mainly Buchia. Wimanfjdlet Mbr, grey shales with sideritic and calcite concretions, 182 m thick at the type locality; relatively poor in fossils; the base is formed by the: Myklegardfjellet Bed, thin plastic glauconitic clay crops out in eastern Nordenski61d Land including Lardyfjellet (40cm) and Glitrefjellet (50 cm) (Dypvik, Nagy & Krinsley 1992) and contains rare belemnites and Berriasian foraminifera (Nagy et al. 1990). The base is erosive. Possibly coeval with Mjolnir impact.

53

Agardhfjellet Fm (Parker 1967) is predominatly argillaceous, but two of the four members are sandy. Generally just over 200 m thick at Janusfjellet and Glitrefjellet, but thins to 100 m on the Billefjorden Fault lineament. Slottsmoya Mbr, grey organic-rich shales with siderite concretions (Dypvik et al. 1991), 90 m thick at the type section, siltier units in the upper part are characterized by ammonites, including Dorsoplanites and benthos. Oppdals~ta Mbr, silts to fine sandstones in three coarsening-upward cycles (Dypvik et al. 1991), 28 m thick at the type locality. Lardyfjellet Mbr, 35 m grey particularly organic-rich shales with dolostone concretions (Dypvik et al. 1991) at the type locality, macrofauna occasional. Oppdalen Mbr, 60m is the basal unit of the Agardhfjellet Formation, generally calcareous and containing coarse clastics, but locally oolitic (Dypvik et al. 1991), it includes three beds. Dronbreen Bed of fining upward sandy to silty clay with sideritic horizons, up to 60m thick (Dypvik et al.1991). Marhogda Bed with a maximum thickness of 1.5 m at the type locality near Diabasodden, south of the mouth of Sassenfjorden, a microsparitic calcarous sandstone, partially dolomitized and sideritized, with quartz grains, chert, ooids and glauconite (B~ickstr6m & Nagy 1985). Brentskardhaugen Bed (Parker 1967) forms the base of the member. At the type locality it is 130cm thick. It contains richly fossiliferous reworked phosphoritic concretions with cherts and quartz in a microsparitc ferruginous dolomitic cement (B/~ckstr6m & Nagy 1985). The base is erosional but without angular discordance on the Wilhelmoya Fro.

4.3.3

Sabine Land

The near horizontally bedded outliers northeast of Agardhbukta include the principal exposures on Agardhfjellet, Myklegardfjellet and Holmgardfjellet (Miloslavskiy 1993, D9G), where there is a complete sequence through the Janusfjellet Subgroup, capped with minor sandstone outliers of the Helvetiafjellet and Carolinefjellet formations. Agardhfjellet lies on the axis of a N N E - S S W minor syncline and Holmgardfjellet on a gentle anticline. The easternmost outcrop just east of Eistraryggen shows an overturned N N E - S S W striking syncline adjacent to a normal fault. There are extensive dolerite sills in the lower part of the Janusfjellet Subgroup in the west, north and east (Birkenmajer 1979). The lower part of the Janusfjellet Subgroup is similarly exposed to the north at D o m e n and Krogfjellet (Miloslavskiy e t al. 1993) and also Teistberget (Miloslavskiy 1992, D8G). At the last locality, N - S monoclinal flexuring and W S W - E N E normal faulting occur. The complete sequence from Glitrefjellet Member to Brentskardhaugen Bed (502 m) has been described from Myklegardfjellet (Birkenmajer 1980). His figure is comparable to a value of 555 m by Pchelina (1967) and of 473 m (based on Parker 1967 and additional data) from the same area.

Section at Myklegardfjellet (Birkenmajer 1980) Carolinefjellet Fm basal unit is present only on Agardhfjellet where carbonate-rich Dalkjegla Member crops out (Bjoroy & Vigran 1979). Helvetiafjellet Fm was formerly over 5 5 m thick and represents an overall fining-upward sequence on Myklegardfjdlet (Birkenmajer 1984) comprising: Glitrefjellet Mbr, 32 m comprizes sandstone shale alternations with minor conglomerates, coal shales, thin coal seams, rootlet horizons representing minor distributaries, channel lags, and interdistributary deposits, with a current direction from the northeast; Festningen Mbr, (c. 23 m) containing large-scale cross-bedded quartz sandstones and lag conglomerates with a sharp erosive base. The cross bedding is mainly planar, with planar and occasionally concave erosional surfaces with megaripples and some slumping. Together with current orientations these features indicate a fluvial system with source from the west. Janusfjellet Subgp, 417.5m is well exposed in Myklegardfjellet and contains eight macrofaunal horizons (Birkenmajer, Pugaczewska & Wierzbowski 1982). Rurikfjellet Fm, with type section on Agardhfjellet, 176m (Parker 1967), also on Myklegardfjellet, 203 m (Birkenmajer 1980), is predominatly shales with common sideritic and dolomitic concretions. It has not been subdivided north of Agardbukta. At the base is: Myklegardfjellet Bed plastic clay, 0.5-1.0 m with erosive base.

54

CHAPTER 4

Fig. 4.4. Geological map and cross-section of eastern Nordenski61d Land and Sabine Land, drawn by S. R. A. Kelly, based on Dallmann (1993) Geological Map of Svalbard 1.'500000, Sheet 1G. This legend serves also for Figs 4.5, 4.6, 4.7 & 4.8.

THE CENTRAL BASIN

55

AgardhfjeHet Fm is 245m on Myklegardfjellet (Birkenmajer 1980) and 241.5 m on Agardhfjellet (Parker 1967)). The section of Birkenmajer (1980) can be subdivided according to Dypvik et al.'s (1991) scheme: Slottsmoya Mbr, 110 m grey organic-rich shales with dolostone concretions; contains Fauna 8 including bivalves and the ammonite Pectinatites of Early Volgian age; Oppdalsfita Mbr, 61 m silts to fine sandstones with faunas 4, 6, 7, mainly of bivalves and 5 of belemnites; LardyfjeHet Mbr, 72.5 m return to grey organic-rich shales with Faunas 1 and 2 mainly of ammonites; Oppdalen Mbr shows a fining-up sequence; Dronbreen Bed, 40 m sands and silts overlying Brentskardhaugen Bed, 0.5m containing fossiliferous phosphoritic and quartzitic pebbles in a dark clayey matrix, resting with erosion on the Wilhelm6ya Formation.

4.3.4

Heer Land

A l t h o u g h m u c h o f the inner part of H e e r L a n d is ice covered, Helvetiafjellet a n d Carolinefjellet f o r m a t i o n s crop out extensively and almost horizontally f r o m the coast westwards, just reaching V a n Mijenfjorden, with only a small a m o u n t of Tertiary cover in the west (Salvigsen & W i s n e s 1989, C10G; Steel, Winsnes & Salvigsen 1989, C10G) (Fig. 4.5). The Janusfjellet F o r m a t i o n has a n a r r o w coastal o u t c r o p reaching s o u t h w a r d s to Kv~lv~gen ( D a l l m a n n 1991, C 11G), forming the base of the cliffs w h i c h are c a p p e d by Cretaceous strata. Extensive dolerite sills occur f r o m K a p p Dufferin n o r t h w a r d s , and affect the Janusfjellet Subgroup. Pavlov & P a n o v (1980) s u m m a r i z e d the geology of H e e r L a n d , recognizing some 971 m o f Cretaceous a n d 240 m of Jurassic strata. The V a l a n g i n i a n / H a u t e r i v i a n - A l b i a n sequences of K j e l s t r 6 m d a l e n , originally described by H a g e r m a n n (1925), and Kvalv{tgen and have been described within a biostratigraphic f r a m e w o r k by Pchelina (1967). The s o u t h e r n m o s t effects of the Billefjorden and L o m f j o r d e n F a u l t Z o n e s are seen in K j e l l s t r 6 m d a l e n a n d on Rurikfjellet respectively.

Carolinefjellet Fm reaches its maximum differentiation in southern Heer Land and northern Torell Land and all five members are recognized; the highest, the Sh6nrockfjellet Formation is restricted to this area and is of Mid-Albian age (Nagy 1970). Helvetiafjellet Fm (100 140m) fluvial sandstones of Kvalvfigen are characterized by quartzose lithic arenites with the quartz derived from the west and volcanics showing affinity with those of Kong Karls Land (Edwards 1978). At least four coals exist up to l m thick, of fusainsemifusainous durain (Pavlov & Panov 1980). Dinosaur footprints, attributed to a carnosaur, occur at Boltodden (Edwards, Edwards & Colbert 1978) in emergent point bar sandstones. Festningen Mbr sandstone forms a 20 m thick channel complex of planar to trough cross-bedded sandstones. The junction deposits of the HelvetiafjeHet Fm and the Janusfjellet Subgroup shows the existence of an unstable delta front which is affected by gravitational movement of slide blocks and is spectacularly exposed at Kv~lvagen (Nemec et al. 1988a). Whole blocks up to 80 m across and including both units have broken away from an arcuate scarp and rotated during down-slope movement from a delta-front. Janusfjellet Gp outcrops. Ullaberget Mbr a generally coarsening upwards sequence of shaley mudstones with thin massive, cross and plane bedded sandstones.

4.3.5

Eastern Torell Land

L o w westerly dips in the Helvetiafjellat and Carolinefjellet f o r m a t i o n s continue in eastern Torell L a n d . Janusfjellet S u b g r o u p no longer crops out on the coastal cliffs, whose base is n o w Cretaceous from Kvalvftgen south to H a m b e r g b u k t a . The higher parts of the coast a n d m o s t of the inland o u t c r o p is Paleogene (Birkenmajer, N a g y & D a l l m a n n 1991, C12G) (Fig. 4.6).

Carolinefjellet Fm is fully developed as in southern Heer Land and reaches 810m at Sch6nrockfjellet a near maximum recorded thickness of 840m at Kostinskifjellet and thickens further southwards beneath the Firkanten Formation unconformity (Nagy 1970).

Fig. 4.5. Geological map of the east coast of Spitsbergen from Agardhbukta to Hambergfjellet, drawn by S. R .A. Kelly, based on Dallmann (1993) Geological Map o f Svalbard 1:500 000, Sheet 1G (see Fig. 4.4 for key).

Schiinrockfjellet Mbr, 83m at the type locality on Sch6nrockfjellet, predominantly cliff-forming fine grained sandstones, with rare bivalves and crinoids. Becomes muddier southwards and passes laterally into the Zillerberget Mbr (c. 350 m). Langstakken Mbr, up to c. 50m but passes laterally into Innkjegla or Zillerberget Mbr southwards. Innkjegla Mbr, c. 120 m. Dalkjegla Mbr, c. 50 m. Helvetiaqellet Fro. 4.3.6

Sorkapp Land

The o u t c r o p p a t t e r n in S o r k a p p L a n d increases in complexity s o u t h w a r d s and westwards, whose interpretation is h a m p e r e d by considerable ice cover e.g. in the central S o r k a p p f o n n a (Winsnes et. al. 1993, C 13G). In the northeast, b r o a d N N W - S S E fold axes are

56

CHAPTER 4

Fig. 4.7. Geological map and cross sections of the Adventdalen Group in Sorkapp Land, drawn by S. R. A. Kelly, based on Dallmann (1993) Geological Map o f Svalbard 1: 500000, Sheet IG and Winsnes et al. (1993) Geological Map of Svalbard 1 ."100 000, Sheet C13G.

Fig. 4.6. Geological map and cross sections of the Adventdalen Group in Wedel Jarlsbert Land and western Torell Land, drawn by S. R. A. Kelly, based on Dallmann (1993) Geological Map of Svalbard 1-500 000, Sheet 1G.

seen in Cretaceous rocks, but dips remain low and there is a small a m o u n t of n o r m a l faulting. In the south of Sorkapp L a n d N W - S E normal faulting and associated folding cause disjunct outcrop pattern. At K i k u t o d d e n on the coast and inland on Keilhaufjellet, E-dipping (20-45 ~) Jurassic and Cretaceous rocks are exposed. The top of the Cretaceous rocks crops out on the west and n o r t h flanks of D u m s k o l t e n , where a small synclinal fold again brings the Tertiary to sea level and Cretacous outcrop is interrupted on the coast. The Cretaceous-Jurassic sequence next appears in a comparable situation, although steep and overturned in proximity to a N N E - S S W - s t r i k i n g thrust, from Gideanoyfjellet and Smalegga to the south coast of inner H o r n s u n d at Brepollen (Fig. 4.7).

A series of small outliers is largely controlled by normal faulting in south and central western Sorkapp Land. Janusfjellet F o r m a t i o n outliers resting on K a p p Toscana G r o u p occur on the summit of Kistefjellet, Oyrlandssleira (with Helvetiafjellet Formation), and Stormbukta. In northeast Sorkapp Land, a Cretaceous-Jurassic sequence resting on Triassic, crops out in a series of thrust slices on Lidfjellet. In a largely biostratigraphical account, Pchelina (1967) described the whole Jurassic and Cretaceous sequence, based on a generalized section t h r o u g h eastern Keilhaufjellet, eastern foot of Kistefjellet and shore cliffs at Austerbogen. Only in parts can this be related to m o r e recent lithic schemes.

Carolinefjellet Fm reaches its greatest measured thickness under the Firkanten Formation erosion at Tromsobreen where 850m have been recorded (Nagy 1970). Here the the Zillerberget Member is the highest unit recognized. The sandy Sch6nrockfjellet and Langstakken Members do not reach this far south. Zillerberget-Innkjegla Mbr undifferentiated shales and siltstones, c. 850 m at Havkollen and thins to 630 m at Keilhaufjellet. Dalkjegla Mbr sandy siltstones and argillite alternations thin southwards from c. 40 m to 60 m. Late Aptian heteromorph ammonites occur (Pchelina 1967).

THE CENTRAL BASIN

Helvetiafjellet Fm, 58 m comprises fining-upward cycles at Kikutodden (Edwards 1976). Pchelina (1967) identified macrofloras of Barremian to probable Aptian age. Glitrefjellet Mbr, 33 m two principal sand-mudstone cycles occur representing channel to floodplain deposits. Festningen Mbr, 25 m two alluvial channel sandstone cycles with conglomeratic bases occur, with transport direction principally from the NW and SW-W. Janusfjellet Subgp Rurikfjellet Fm is not clearly divided. Pchelina (1967) recognized three lithofacies in the Hauterivian part: at the top sandy siltstones (c. 45 m), in the middle a carbonate siltstone (c. 15 m) and at the base mudstones (30 m). The middle calcareous unit may well be related to calcareous units at comparable levels in Kong Karls Land and offshore. Clayey siltstone with carbonate concretions occupy c. 175m of Valanginian to Volgian strata. There is possibly a sandy mid-Volgian interval (c. 15 m). Agardhfjellet Fm, c. 170m mudstones to muddy siltstones with early Volgian to Callovian (probably also Bathonian) fossils. It may be possible to recognize a slightly coarser median. Oppdalsfita Mbr, with Oxfordian fossils, of c. 60 m thickness. Brentskardhaugen Bed, 0.2-0.3m (Pchelina 1967) overlies c. 10m of arenacous and conglomeratic Kapp Toscana Group sediments.

4.3.7

Wedei Jarlsberg Land and western Torell Land

J u r a s s i c - C r e t a c e o u s strata strike N N E - S S W f r o m inner H o r n s u n d in western Torell L a n d , to V a n K e u l e n f j o r d e n n o r t h e r n Wedel Jarlsberg L a n d , with o u t c r o p interrupted by ice cover and m a d e complex by N N W - S S E thrust-faulting ( D a l l m a n n et al. 1990a, b B l l G ) . M u c h of the central to n o r t h e r n part o f the area was m a p p e d originally at 1:50000 by Rozycki (1959). The broadest outcrops are of Cretaceous strata at the west flank o f the Central Basin and include Zillerberget at the north. H e r e easterly dips are m o d e r a t e to low. Except in the north, Jurassic outcrops are n a r r o w a n d dips are steep to overturned. A r o u n d P e n k b r e e n and R e i n o d d e n in the north, Jurassic strata are repeated twice because of faulting. The f o r m e r wider distribution of Jurassic outcrops is shown by the outliers west o f P e n k b r e e n and Finsterwalderbreen. The outcrops of n o r t h e r n W e d e l Jarlsberg L a n d are all influenced by thrusting. T h e wide Janusfjellet o u t c r o p is related to the m a i n o u t c r o p of H u m p v a r d e n a n d is caused by a series of folds. The outcrops of Tilaberget a n d Leinbreen are outliers directly affected by thrusting, while the R e i n o d d e n o u t c r o p is a n o r m a l faulted outlier with an o v e r t u r n e d Janusfjellet a n d Helvetiafjellet sequence. Elsewhere dips are n o r m a l l y low a n d only locally are steep to overturned. Small Janusfjellet S u b g r o u p inliers occur west o f Storbreen (Birkenmajer, N a g y & D a l l m a n n 1991) at south Grimfjellet and west M e z e n r y g g e n in gently folded strata c o m p a r a b l e to that o f Cretaceous strata in n o r t h e a s t S o r k a p p Land. Intrusive dolerite dykes occur on the south o f Bellsund (Hauser 1982). General descriptions of the J u r a s s i c - C r e t a c e o u s sequence in southwest Torell L a n d have been given by R o z y c k i (1959) a n d Birkenmaj er (1975).

Carolinef]ellet Fm totals about 700m thickness in northern Wedel Jarlsberg Land (Nagy 1970), with the four lower members represented on Zillerberget. Major sections have not been measured in the south, although the base is recognized at Polakkfjellet where dark arenaceous shales of the Dalkjegla Member occur, and equivalent strata crop out on Blfikettane and Isskiltoppane (Birkenmajer 1975). Zillerberget Mbr, 210 m at the type locality comprizes distal shelf shales and siltstones with minor sandstones and clay-ironstone concretions. The top of the member contains Middle Albian ammonites and is eroded under the Firkanten Formation unconformity. Langstakken Mbr, 40 m but passes laterally into Innkjegla or Zillerberget Member southwards. Innkjegla Mbr, 321m shales to shales with siltstones containing Early Albian ammonites, including Arcthoplites and Freboldiceras faunas. Dalkjegla Member, c. 130m sandy siltstones. Helvetiafjellet Fm comprizes three principal coarsening-upward cycles in western Torell Land (Birkenmajer 1975, 1984).Typical Glitrefjellet and Festningen member lithologies are present in some localities, not so clearly

57

demarcated at Cholmfjellet where thick alluvial channel facies in the upper part of the Formation (as opposed to the base), indicate the proximity of an easterly source for clastics from the Hornsun&Sorkapp High. The base of the Helvetiafjellet Formation is generally marked by erosion and at Bendefjellet the top of the Janusfjellet Subgroup is penetrated by rootlets from above, suggesting subaerial conditions. The basal Helvetiafjellet Formation unit in the area is usually a non-marine shale-sandstone unit. Festningen Mbr where it can be recognized, varies in thickness at Hyrnefjellet (50-60 m), Bendefjellet (45 m) and Polakkfjellet (20 m).

Janusfjellet Subgp Rurikfjellet Fm thickens northwards. There is marked thinning to less than 100m centering on southern Wedel Jarlsberg Land, and forming the Serkapp Hornsund-High. In northern Wedel Jarlsberg Land thicknesses increase to over 200 and over 400 m respectively in these formations. Ullaberget Mbr comprizes regressive sandstones of the Formation. In the southwest at Bendefjellet the member is only 6 m thick, comprising a single unit of bituminous and glauconitic sandstone with plant detritus; at Hyrnfjellet it is 10-20m and 65m at Polakkfjellet. Northwards it reaches c. 150m at Reinodden and 119.5m at Jurakammen. At Bendefjellet it is penetrated by rootlets originating in the Helvetiafjellet Fm. Wimanfjellet Mbr was originally recognized in this area as the Tirolarpasset Mbr (Rozycki 1959), with type section at Jurakammen where it is 187.5m thick. It comprizes uniform siltstones and shales with clay-ironstones. The base of the Member is the: PolakkfjeHet Bed, which is only recognized in Wedel Jarlsberg Land, a conglomerate of clasts of ferruginous sandstones and quartz pebbles, which rests on a significant erosional base. The break probably lies within the Volgian stage or at its base on an eroded Kimmeridgian surface (Birkenmajer 1975; Birkenmajer & Pugaczewska 1975). The bed is 5m thick at Polakkfjellet and stated to be 46.34m in the Jurakammen section (Birkenmajer 1975). Dypvik et al. (1991) correlate this bed with comparable sandstones in the formation below. Agardhfjellet Fm corresponds in this area to the Ingebrigtsenbukta Mbr of Rozycki (1959) with type section at Ingebrigtsenbukta on the south coast of Van Kuelenfjorden. At Jurakammen the unit is 285 m thick comprising shales and siltstones with clay ironstone concretions. It is widely exposed, but thins southwards to Polakkfjellet (150m), Hyrnefjellet (110 m), south Fonnryggen (60 m), Somovfjella and Somovaksla (both 40 m) (Birkenmajer 1975). Although the upper members of the formation have not been identified in the area, the Oppdalen Mbr is recognized at the base. Forming the base of the Agardhfjellet Fm is the Brentskardhaugen Bed which varies locally in lithology: at south Fonnryggen it is a poorly cemented fossiliferous phosphorite pebble concentrate (0.1-0.2 m); at Hyrnefjellet it contains black phosphorite pebbles in black shale matrix or is a wellcemented conglomerate of quartz, fossiliferous phosphorite and ferruginous ooids with siderite, grading up into sandstone (0.2-0.5 m). The latter may indicate existence of the Marhogda bed. At Skiferkammen the Brentskardhaugen Bed shows reverse grading and at Tilasberget in the lower part it is normally graded and in the upper part reverse graded (Maher 1989) with no angular discordance at its base. No positively Jurassic fossils have been reported from this area, (Krajewski 1992).

4.3.8

Western Nathorst Land

In M i d t e r h u k e n , west N a t h o r s t L a n d ( D a l l m a n n et al. 1990, B11G; Hjelle et al. 1985, B10G), a simple, m a i n l y easterly dipping o u t c r o p of A d v e n t d a l e n G r o u p lies between the K a p p T o s c a n a a n d V a n M i j e n f j o r d e n groups with several m i n o r Helvetiafjellet F o r m a t i o n outliers resting on the Janusfjellet Subgroup. The o u t c r o p is u n i n t e r u p t e d between V a n K e u l e n f j o r d e n and V a n Mijenfjorden. The b r o a d JanusfjeUet S u b g r o u p o u t c r o p is caused by strikeparallel N - S fold axes, a syncline o f w h i c h passes t h r o u g h the Helvetiafjellet o u t c r o p on A n n a b e r g e t . M u r o s k o has described dolerite intrusions into b a s e m e n t rocks on the M i d t e r h u k e n peninsula (Fig. 4.8).

Carolinefjellet Fro, although a relatively full sequence of the Dalkjegla to Zillerberget members is represented in western Nathorst Land, the youngest date is Early Albian (Nagy 1970). Helvetiafjellet Fm Festningen Mbr coarse massive sandstones rest sharply on the Janusfjellet Subgroup.

58

CHAPTER 4 ,,,,,,,,,,,,,,,,,,,,

,

Kvaevefjellet III~._~_oldiabukta

t!l!!

// ////

/,, OSCAR I I / / LAND

~ fjellei:ll'~r )

~

Ullaberget Mbr is 151.5m thick at the type locality on Ullaberget, and is at its maximum development. It comprizes regressive sandy shales and siltstones with minor micaceous sandstones. Janusfjellet Subgp Oppdalen Mbr is represented on Midterhuken by over 7m of calcareous sediments with ooliths and is comparable to the Marhogda Bed (Maher 1989) but in the middle of which there is the Brentskardhaugen Bed (1 m), immediately above a stromatolite rich layer. (Krajewski 1990, 1992).

o.e'aof, yal Bohemannesset

yf

~ //

Is fj o r d e n

Sylodden

Van

kk ~

Bellsund

Midterhuken ~ s

%

Western Nordenski61d Land

In western Nordenskiold Land, the Adventdalen Group crops out from between Berzeliusdalen on the north shore of Van Mijenfjorden, where it is largely obscured by drift, northwards to Gronfjorden, with the classic Festningen sequence on the south shore of Isfjorden. To the east the Cretaceous sequence dips at low angle, eastwards under the Tertiary unconformity. To the west the Janusfjellet Subgroup and the Helvetiafjellet Formation dip at moderate to high angle, and include the near vertical sandstones at Festningen itself. The Festningen section is one of the most accessable Jurassic-Cretaceous sections on Svalbard with an almost completely exposed sequence of Adventdalen Group strata exposed in low level coastal cliffs (Frebold 1928; Frebold & Stoll 1937; see Fig. 4.1).

k

A

4.3.9

Erdmanflya

Ramfjellet

Mijenfjorden ~

~ : : . j . . i.~LAN r

A' Erdmannflya 1000

~~l,,fr,1,

....

0m -1000 -2000

Gronfjorden

Carolinefjellet Fm is at its thinnest at Festningsodden, where only 180 m including only the lowermost two members occur under the basal Tertiary erosion surface. Steel, Gjelberg & Haar (1978) interpreted coarsening upwards cycles as of lower delta front facies. Inkjegla Mbr Dalkjegla Mbr Helvetiafjellet Fm non-marine sequence includes: Glitrefjellet Mbr, sands and silts are recessive. Steel, Gjelberg & Haar (1978) demonstrated distributary channel sandstones; Festningen Mbr, crevasse channel sandstones, levees, crevasse splays and interdistributary bays massive sandstones are well exposed in the, 29.5 m at Festningen itself. Frequent conglomerates indicate reworked earlier Jurassic, Permian, Carboniferous and possible Early Paleozoic deposits represented elsewhere on Spitsbergen (Parker 1967). Fossil footprints indicate the presence of a dinosaur, Iguanodon (de Lapparent 1962). Janusfjellet Subgp Agardhfjellet Fm Rurikfjellet Fm Marhogda Bed, 40 cm Brentskardhaugen Bed is only 5 cm thick although it thickens southwards to 45 cm at Vardebreen (B/ickstr6m & Nagy 1985) and crops out on the south coast at Flathaugen (Maher 1989). It occurs above transgressive sandstones of the Wilhelmoya Formation.

g w

1000 Om -1000 -2000

Fig. 4.8. Geological map and cross sections of the Adventdalen Group in Oscar II Land, Nordenski61d Land and Nathorst Land, drawn by S. R. A. Kelly, based on Dallmann (1993) Geological Map of Svalbard 1: 500000, Sheet 1G and for the Ramfjellet section, based on Ohta et al. (1991) Geological Map of Svalbard 1:100 000, Sheet B9G.

4.3.10

Central Nordenski61d Land

The relatively few published records of the sequence from the centre of the Central Basin beneath the Paleogene cover include the sequence of the Grumant borehole which was made on the north side of Colesbukta. Cretaceous to Jurassic rocks were encountered at depths from 4 5 0 m to 2620m and were described from a biostratigraphical basis by Shkola et al. (1980):

Early Cretaceous, 1000 m: Aptian-Albian, 120 m upward-fining sands to argillites. Barremian, 115 m sandstones with coals. Hauterivian, 115 m silts becoming sandier upwards. Valanginian, 220 m argillites. Berriasian, 160 m argillites with siderite. Jurassic, 350 m: Volgian, 165 m argillites Kimmeridgian, 110 m argillites Oxfordian, 45 m Callovian, 30 m sandy silts. Burial palaeotemperatures of the Early Cretaceous and Late Jurassic rocks were of 160-190~

THE CENTRAL BASIN

4.3.11

Oscar II Land

The outliers of Oscar II L a n d represent the relics of the n o r t h e r n closure o f the o u t c r o p o f the A d v e n t d a l e n G r o u p of the Central Basin. Jurassic strata rest on Triassic intermittently exposed from the west side of Y m e r b u k t a , t h r o u g h Ramfjellet and Syltoppen to Y o l d i a b u k t a , a n d is disrupted by faulting. Cretaceous rocks occur at a n d near the coast n o r t h of E r d m a n n f l y a and B o h e m a n n e s s e t a n d on Ramfjellet a n d Syltoppen (faulted) (Ohta et al. 1991, B9G). At B o h e m a n n e s e t coal was m i n e d in the early 1920s. The o u t c r o p p a t t e r n at Sylodden matches that at Festningen, on the south side o f Isfjorden, but is offset by thrust faulting in Isfjorden w h i c h strikes N N E - S S W . Here a complete Janusfjellet S u b g r o u p sequence, capped by Helvetiafjellet sandstones, occupies a syncline striking N N W - S S E , parallel to the b e d d i n g strike. The JurassicCretaceous sequence is repeated in the outliers by several thrust fault slices in the higher part of Ramfjellet, but separated by a thrust fault f r o m S - S E (5-20 ~ dipping Cretaceous, including Helvetiafjellet, sandstones. The most northerly outcrops are B o h e m a n n e s s e t a n d Kv~evefjellet where a low-dipping sequence of Janusfjellet a n d Helvetiafjellet is cut by a series of thrusts exposed on the higher ground.

Helvetiafjellet Fm Glitrefjellet Mbr, at Bohemanesset macroflora is abundant including Elatides, (Sveshnikova & Budantsev 1969) Ginkgo, Podozamites, Pseudotorellia and 'Sciadopitys-like' leaves (Bose & Manum 1990).

Festningen Mbr RurikfjeUet Fm Ullaberget Mbr, 100 m is predominantly sandstone, comprises two coarsening upwards cycles showing hummocky cross-stratification, followed by parallel lamination and intense bioturbation (Dypvik et al. 1991; Hvoslef, Dypvik & Solli 1986; Oxnevad 1985).

Wimanffjellet Mbr Mycklegardfjellet Bed is present (Dypvik et al. 1991). Agardhfjellet Fm is well exposed at Bohemanflya where it is particularly thick (260 m), Dypvik et al. (1991) gave the following sequence: Slottsmoya Mbr, 75 m upward-fining sands shales; Oppdalshta Mbr, 95 m paper shales and a 30 m thick organic-rich muddy sandstone; the latter generally macrofossil-rich, including bivalves, ammonites and belemnites; Lardyfjellet Mbr, 20 m paper shales; Oppdalen Mbr, 60m reaches its maximum thickness at Syltoppen, mainly Dronbreen Bed, sandy shales, becoming sandier upwards; and at the base, the Brentskardhaugen Bed, rests with erosion on the Wilhelmoya Formation.

4.4

The Kapp Toscana and Sassendalen Groups (Liassic, mainly Triassic)

Strata of the K a p p T o s c a n a a n d Sassendalen groups crop out extensively in S v a l b a r d - the larger area being in the east where they are described in C h a p t e r 5. H o w e v e r , the Central Basin contains the type sections for all except the u p p e r m o s t (Wilhelm o y a ) formations. W i t h the exception o f part of this f o r m a t i o n , w h i c h ranges up to T o a r c i a n age, the two groups are wholly Triassic in age. T h e n o m e n c l a t u r e a n d classification o f lithic units are discussed m o r e fully in C h a p t e r 18 a n d the f a v o u r e d scheme is a d o p t e d here. Place names are s h o w n on Fig. 18.1.

4.4.1

Lithic scheme for Kapp Toscana and Sassendalen Groups in the Central Basin

The distribution of rock units is s h o w n in the fence d i a g r a m (Fig. 4.9).

Kapp Toseana Group. This unit was originally defined as a formation with two members (Buchan et al. 1965) and they were raised in rank to

59

group (Harland et al. 1974) so that the Group was constituted by the two formations: De Geerdalen and Tschermakfjellet from which a third formation (Wilhelmoya) was distinguished at the top (Worsley 1973). The fence diagram (Fig. 4.9) shows the uniform strata throughout. Plant remains are common everywhere. Ammonites, bivalves and some gastropods occur in marine beds where also fish and reptile remains and trace fossils (Rhizocorallium and Diplocraterion) are found. Ages from Late Ladinian for the Tschermakfjellet Formation through Norian and Rhaetian for the Wilhelmoya Formation are indicated. Wilhelmnya Formation (Worsley 1973). Worsley included the Brentskardhaugen Bed at the top of his formation. It is not, however, described in the type section nor is it evident in the main development of the formation in the Eastern Platform (Chapter 5). Moreover that 'Lias conglomerate' was originally included in the Janusfjellet Formation (Parker 1966) and although subsequently taken within the De Geerdalen Formation (e.g. Buchan et al. 1965), it has latterly resumed its position as a basal conglomerate of the Janusfjellet Subgroup (e.g. Dypvik et al. 1991) and that is adopted here. The consequence is that whereas the restricted Wilhehnoya Formation is well developed in the Eastern platform and the Brentskardhaugen Bed is traceable through the Central Basin, the beds below it in the Central basin are not so easily distinguished lithologically in the Central Basin from the body of the de Geerdalen Formation as originally described. The age range of the Wilhelmoya Formation is probably Norian-Toarcian (Worsley 1973; Bjaerke & Dypvik 1977; B~ickstr6m & Nagy 1985). The Wilhelmoya Formation differs in its terriginous fraction from the rocks below being more mature in its sandstone content. It it much thicker in the Eastern Platform (Chapter 5). In the Central Basin its maximum thicknesses is in the south. It is much thicker in the Eastern Platform (Chapter 5). In the Central Basin its maximum thickness is in the south. De Geerdalen Formation (Buchan et al. 1965). Originally defined as a member this unit is largely a non-marine sequence of fine- to mediumgrained grey-green plant-bearing sandstones, weathering greenish and brown, laminated to massive, interbedded with varying amounts of grey silty shales, shaly siltstones and harder calcareous siltstones. It includes the Plateau flags of Gregory (1921) and possibly the Fosse Sandstone of Hoel & Orvin (1937). It was named from the valley (De Geerdalen) to the west of Botneheia. The composition is generally of immature sandstones with 50% or less quartz, 33% feldspar and up to 30% of rock fragments (Pchelina 1965a; Lock et al. 1978). Mork, Knarud & Worsley (1982) reported that the predominantly sandy De Geerdalen Formation consists of recurrent small and large scale sequences, upward coarsening from grey shale to very coarse grained sandstone, where at the top they were reworked by waves and bioturbated. They show channelling, hummocky and herringbone cross-bedding with many erosive contacts. Most types of ripples occur as well as lenticular, wavy and flazer bedding. A high energy environment is indicated by protective burrows and mud clasts. In the lower sandstones, cementing is by interstitial clay minerals. Tschermakfjeilet Formation (Buchan et al. 1965). Similarly, at first a Member of the Kapp Toscana Formation, this unit is distinctive but not uniformly extensive. It included the Oozy Mound Beds and Upper Nodule Bed of Gregory (1921), the Upper Daonella layers of Wiman (1910a). The upper part included the Halobia shales of Stolley (1911), his Nathorstites Niveau and his Lingula Sandstone. It is the upper Saurian Niveau of Wiman (1910b) and the Lindstroemi Sandstone of Frebold (1930b). This formation is indeed a richly fossiliferous unit with an age range from Late Ladinian to (Late) Carnian. This unit is recognized in the eastern and southern outcrops of the Central Basin and further east in the Eastern Platform. The dark shales, siltstones and fine sandstones are distinguished by their small red-weathering clay ironstone concretions which contain a rich ammonite and bivalve fauna. The unit is overlain by the lowest hard sandstone of the De Geerdalen Formation. It is underlain by the siliceous siltstone marker at the top of the Botneheia Formation. The unit also appears in southern Spitsbergen (shown as such in sections by Mork & Worsley 1979) and was then named the Austjokelen Formation by Mork et al. 1982). These southern facies differ in having fewer siderite nodules and occasionally none. It is noteably absent in the western fold belt where the thicker and sandier facies dominate. Sassendalen Group (Buchan et al. 1965). The Sassendalen Group was defined as comprising three formations: Botneheia, Sticky Keep and Vardebukta all from the Central Basin. The two upper formations comprised the Kongressfjellet Subgroup; but this is not often used. It is a clearly defined unit between the Kapp Toscana Group above and the

60

CHAPTER 4

Fig. 4.9. Fence diagram showing the distribution and thickness variation of the Sassendalen and Kapp Toscana groups, based on Buchan et al. (1965) except for section south of Kapp Lee. Tempelfjorden Group below except where there is a lithological gradation upwards into the Tschermakfjellet Formation. The three formations have been recognized satisfactorily throughout the Central Basin as was demonstrated by Mork & Worsley (1979). However, Mork, Knarud & Worsley (1982), in the course of a systematic sedimentological analysis, while adopting the same threefold classification, changed the nomenclature significantly, some aspects of which are not followed here. For example, because in Barentsoya and Edgeoya, where the three formations are not readily distinguishable and where Lock et al. (1978) for this reason introduced a single Barentsoya Formation (Section 5.7) Mork et al. (1982) reduced the three original formations to members within

the Barentsoya Formation which then became in effect the Sassendalen Group. The seven new names that were introduced for the other outcrops of the Sassendalen Group will be mentioned in the description of the three original Formations which defined the Group. Kongressfjellet Subgroup. The Subgroup comprises the Botneheia and Sticky Keep formations. Botneheia Formation, 157m (Buchan et al. 1965). The type section was measured at Vikinghogda and is well exposed to the west on Botneheia. The formation is traceable throughout Spitsbergen except that it is not so distinctive in the northeast (Section 5) and in Sorkapp Land. It is a dark grey shale sequence weathering blue black and dark grey.

THE CENTRAL BASIN The upper part is of papery, laminated, bituminous (2-11% TOC) shales or occasionally concretions of grey silty limestone (Daonellenkalk of Mojsisovics 1886). They form a distinctive escarpment (Escarpment Shales of Gregory 1921). They are equivalent to the Oil Shale Series in Edgeoya (Falcon 1928), and the Ptychites beds of Spath (1921). The lower part is of softer shales with siltstone interbeds and small phosphatic concretions, generally less than 2 cm diameter, weathering blue black, these increase to 50% of the rock at the base. Mork et al. refer to the upper part as Blanknuten Beds i.e Blanknuten Member of the formation. On the west coast they refer to the formation as the Bravaisberget Formation with an upper Somovbreen Member and a lower Passhatten Member. Their Bravaisberget Formation appears to be mainly represented by their Karentoppen Member. Bivalves are especially common and the age range would be Anisian to Early Ladinian. Sticky Keep Formation, 121 m (Buchan et al. 1965). In the type section on Vikinghogda and to the east in Sticky Keep this formation is distinguished from the softer Botneheia beds above by a cliff-forming yellow-weathering topographical ledge of siltstone. Septarian concretions (10cm to l m diameter) are common in the lower part. Ammonoids, bivalves and bone fragments occur throughout. A Smithian-Spathian age is thereby indicated. The formation includes the Posidonomya layers of Nathorst (1910) the same as the Posidonomya limestone of Mojsisovics (1886), the Fish Niveau of Wiman (1910, Arctoceras layers of Stolley (1911), the lower Posidonomya shales of Spath (1921), the Arctoceras horizon of Frebold (1930a) The upper part contains the lower Saurian Niveau and Grippia Niveau ofWiman (1910a) and (1928), and the Saurian Bed and the lower part of the Upper Posidonomya Shales of Spath (1921). The lower part contains the lowest Nodule Bed of Gregory (1921), the Anasibirites horizon of Spath (1921) and the Goniodiscus nodosus horizon of Frebold (1930a). There are thickness variations over the Billefjorden Fault zone. In the west coastal sections Buchan et al. (1965) distinguished two members at Iskletten in Oscar II Land. However two such members can be traced through most of the Central Basin though not into the Eastern Platform. Kaosfjellet Member, 76 m is named from the chevron folding at lskletten and fi'om Kaosfjellet. It is of laminated shaly siltstones alternating between softer yellow-weathering and harder grey-weathering. Iskletten Member, 154 m is the lower uniform shaly part of the Sticky Keep Formation and is characterized i.a. by grey septarian limestone concretions especially in the upper part. Fossils are not common except in the concretions. The Sticky Keep Formation is readily distinguished in the Festningen section at the south western entrance to Isfjorden, however, Mork et al. (1982) have used a local name for it (the Tvillingodden Formation). Above the Hornsun&Sorkapp High they gave a further name: the Kistefjellet Formation. The extra nomenclature was introduced to match their sedimentological interpretations of the sequence. Vardebukta Formation, 253.5m (Buchan et al. 1965). The lowest formation of the Sassendalen Group (and below the Kongressfjellet Subgroup) is best exposed at Vardebukta in the Festningen section to the west of the basin where the type section was described. It is characterised by sandstones with interbedded siltstones and shales. Similar lithologies are evident in Sassendalen and Dickson Land but the sections are often obscured by scree and float, from which a similar stratigraphy can be deduced. The best exposure in the east may be at Deltadalen which name Mork et al. introduced for a parastratotype section and named it there as a unit (member) in place of the original Vardebukta Formation as mapped there. The Vardebukta Formation has been divided into two members: Siksaken and Selmaneset. Siksaken Member, 104 m (Buchan et al. 1965) is named from Siksaken with its sharp folds in Oscar II Land and described from Iskletten composite section. The member consists of alternating grey calcareous, silty limestone, calcarenite, light grey and white sandstone, hard siltstones and calcareous shales. Fossils are common. It is distinguished by its contrasting hardness from the more shaly member below. The member includes the Pseudomonotis shale and Retzia limestone of Lundgren (1887) and the synonymous Hustedia limestone of Nathorst (1910). Selmaneset Member, 136m (Buchan et al. 1965) is named from the eastern promontory at the entrance to Trygghamna in Oscar II Land. It is of dark grey often calcareous silty shales and distinguished from the overlying member by its lesser resistance to weathering. Fossils are not common, however, the member was thought by Buchan et al. to include the Myalina Shale of Lundgren (1883) and the Claraia zone of Frebold (1936).

61

The Vardebukta Formation if present on the Hornsundet-Sorkapp High is very thin (28 m Worsley & Mork 1978) and may be represented by the Brevassfjellet Bed of Mork et al. (1982). In the following regional outline the lithologies as described above are sufficiently c o n s t a n t for the principal f o r m a t i o n s as described above to be recognized t h r o u g h o u t m o s t of Spitsbergen as d e m o n s t r a t e d by B u c h a n et al. (1965) a n d M o r k & Worsley (1979). C o n s e q u e n t l y to s u m m a r i z e the lithologies in each of the following areas w o u l d involve m i n o r variations on basic characteristics so similar as to confuse rather t h a n to clarify. There is, of course, far m o r e i n f o r m a t i o n in the original description of each section. B u c h a n et al. (1965) described the lithologies and the positions of fossil collected. M o r k & Worsley (1979) and M o r k et al. 1982 logged detailed sedimentary characters for sedimentological interpretations. The thickness estimates of each unit are derived from the published s e c t i o n s - the B u c h a n et al. values as recorded are in italics. The other values have generally been estimated f r o m the published sections.

4.4.2

Sassendalen to Storfjorden (southern Sabine Land)

F r o m Sassenfjorden along the cliffs and slopes of the m o u n t a i n s south of Sassendalen and t h r o u g h to A g a r d h b u k t a in S t o r f j o r d e n is the belt of outcrops w h e r i n the strata between the P e r m i a n K a p p Starostin a n d the Jurasssic A g a r d b u k t a f o r m a t i o n s are well displayed. T h e y are nearly fiat-lying and tectonically have suffered relatively m i n o r disturbances. M o r e o v e r their fossiliferous facies has c o n t r i b u t e d to this being a classic area of Triassic studies. In these circumstances it was n a t u r a l to establish the lithic scheme of rock units here as described above. In the stratigraphic history of Svalbard the Mesozoic interval was a time of relative tectonic stability with the result that the same lithic units can be m a p p e d t h r o u g h o u t Svalbard with only m i n o r variations. The Sassendalen G r o u p strata rest with slight disc o r d a n c e on the T e m p e l f j o r d e n G r o u p b e n e a t h a n d the K a p p T o s c a n a G r o u p strata are c o n c o r d a n t with the overlying Adventdalen G r o u p albeit with a distinctive n o n s e q u e n c e between them. These rocks crop out in a wide b a n d t o w a r d s the n o r t h e a s t (see Fig. 18.1). T h e y are less well k n o w n there except at W i l h e l m o y a and Hellwaldfjellet where the u p p e r part of the K a p p T o s c a n a G r o u p is especially well represented with the type section of the W i l h e m o y a F o r m a t i o n . But this is treated in the following chapter (5) as part o f the Eastern Platform. In addition to earlier investigations as by G a r w o o d & G r e g o r y (1896) and G r e g o r y (1921) there have been m a n y biostratigraphical and palaeontological studies, for example: the saurian w o r k s o f W i m a n (1910-1933), the a m m o n o i d studies o f L e h m a n n a n d colleagues (Weitschat 1986; Weitschat & L e h m a n n 1978, 1983; Weitschat & D a g y s 1989), and the bivalve studies of C a m p b e l l (1994) (see C h a p t e r 18). The following notes especially the thicknesses are based largely on the w o r k o f B u c h a n et al. (1965), M o r k & W o r s l e y (1979) a n d M o r k et al. (1982). F r o m these sources the succession in this Sassendalen to S t o r f j o r d e n sector is a p p r o x i m a t e l y as follows: Adventdalen Gp Kapp Toscana Gp Wilhelmoya Fm, in area c. 120 Tumlingodden Mbr, 60 m Transitional Mbr, 33 m Bjornbogen Mbr, 19 m Basal Mbr, 7 m De Geerdalen Fm, c. 380 m (at Wilhelmoya) 190m (at Botneheia) Tschermakfjellet Fro, c. 93 m at Vikinghoda, c. 63 m at Botneheia Sassendalen Group Botneheia Fm, 170-146 m at Sticky Keep, 157 m at Vikinghogda, 129 m at Botneheia Sticky Keep Fin, 120m to ?150m at Sticky Keep, 121 m at Vikinghogda, 70 m at Stensi6fjellet

62

CHAPTER 4

Vardebukta Fro, (Deltadalen Mbr of Mork et al.), 130m at Deltadalen, 115 m at Vikinghogda, 125 m at Stensi6fjellet, 129 m at Sticky Keep (102+m at Botneheia) Tempelfjorden Group. Kapp Starostin Formation

4.4.3

Nordfjorden (S Dickson Land and E Oscar II Land)

Successions thin over the old Nordfjorden Block as compared with both east and west. They are seen best to the east in the extensive and accessible outcrops of southern Dickson Land as at the classic Kongressfjellet section Tschermakfjellet and Rotundafjella but also to the west in eastern Oscar II Land at Bertilryggen and Sveaneset. In each case the regional southerly dip has the effect that the De Geerdalen strata have been mostly removed where they dipped into Isfjorden. Kapp Toseana Gp De Geerdalen Fm Tschermakfjellet Fm, 50 m at Tschermakfjellet, 70 m at Kongsressfjellet Sassendalen Group Botneheia Fro, 129 m at Tschermakfjellet, 126 m at Kongressfjellet Sticky Keep Fro, 133m at Rotundafjellet, 120 m at Tschermakfjellet, 112m at Kongressfjellet Vardebukta Fro, 61 m at Tschermakfjellet, 101m at Rotundafjellet, ?70m at Kongressfjellet Tempelfjorden Gp Kapp Starosfin Fro.

4.4.4

Western lsfjorden (SW Oscar II Land and N W Nordenskiiild Land)

West of the Nordfjorden area is the West Spitsbergen orogenic foldbelt which runs parallel to the coast from Kongsfjorden to Hornsund. In this the whole Late Paleozoic-Mesozoic successions are steeply dipping and so of narrow linear/',IS outcrop. Whereas this gives the opportunity in E - W coastal section often to traverse near-vertical strata there are also likely to be structural complications. Of these the section at the southern entrance to Isfjorden, the Festningen section (Hoel & Orvin 1937), is perhaps the best known stratigraphic profile in Svalbard with near-vertical mid-Carboniferous to Paleocene strata. The Triassic rocks being less competent than those below and to the west have therefore been somewhat thrust so that precise correlation and thickness are in question. A further consideration is the fact that the Paleogene orogen coincides approximately with a significant thickening and coarsening of the Triassic strata to the west so that the western margin of the basin has been uplifted and eroded. The fence diagram (Fig. 4.9) demonstrates this thickening with resumption of the Kapp Toscana succession at the top. It could be argued that the postulated Kongsfjorden-Hansbreen Fault which bounds the Nordfjorden High on its west has something to do with this thickening.That fault would have a long pre-Carboniferous history and possibly locate the eastern margin of the Paleogene Orogen. M o r k e t al., on the other hand, postulated an extension southwards of the Pretender Fault which extension seems to have no other supporting evidence. Indeed, there is no need for a fault to mark the thickening. The distance between the two contrasting stratal thicknesses used by M o r k e t al. is 40 or 50 km which, with a thickness difference of up to 500 m represents a maximum cumulative gradient of 1% (less than one degree). The slope could be increased by aligning the fault more closely to the two isopach points but then it would not align with the proposed faults. Moreover, M o r k e t al. did not use the southern Oscar II Land data of Buchan e t al. These gave intermediate thicknesses, i.e. not so thick values as at Festningen. Adventdalen Gp Kapp Toscana Gp. Formations are not distinguished. The group thickness at the northern entrance to Isfjorden is 207m (i.e in southern Oscar II Land) and at the southern entrance (Festningen section) is 327.5 m.

Sassendalen Gp Botnieheia Fm (= Bravaisberget Fm at Festningen of Mork et al.) Somovbreen Mbr is 262m at northern entrance and 243.5m at southern entrance to Isfjorden. Sticky Keep Fm (= Tvillingodden Formation at Festningen of Mork et al.) with a Skilisen Bed near the middle): 130 to 230m at northern entrance, 300.5 m at southern entrance to Isjforden. At the northern entrance two members were defined by Buchan et al. Kaosfjellet Mbr, 76m in N 122m in S Iskletten Mbr, 154m in N 178.5m in S Vardebukta Fin (Buchan et al. and Mork et al.), 233 m in the N 253.5 m in S. Two members were distiguished by Buchan et al. in southern Oscar II Land. Siksaken Mbr, 104m at Iskletten in N; 95.5m in S Selmaneset Mbr, 129m at Selmaneset in N; 158m in S.

4.4.5

Van Keulenfjorden (W Nathorst Land and N Wedel Jarlsberg Land)

The outcrops at the entrance to the two fjords branching eastwards from Bellsund similarly show thick successions within the foldbelt. In Western Nathorst Land at Bravaisberget north of Van Keulenfjorden is a key section measured by both Buchan e t al. and M o r k e t al. as follows and Buchan e t al. combined it with the section south of the fjord at Kapp Toscana. Adventdalen Gp Kapp Toscana Gp, 200 m Wilhelmoya Fm, c. 7 m De Geerdalen Fro, 193 m (Tschermakfjellet Fm not distinguished) Sassendalen Gp Botneheia Fm (= Bravaisberget Fm, Mork et al.), 215 m. Sticky Keep Fm 312m (Tvillingodden Fm of Mork et al. c. 280m). Kaosfjollet Mbr, 92 m Iskletten Mbr, 220 m Vardebukta Fro, 142-160m Siksaken Mbr, 62 m Selmaneset Mbr, 80 m

Tempelfjorden Gp. In northern Wedel Jarlsberg Land the cliff sections at Reinodden and at Ahlstrandodden were described in lithic and biostratigraphic terms by Nakazawa e t al. (1990). They followed and amplified in detail the Sassendalen units of Buchan et al. (1965). In broad outline the succession was given thus: Kapp Toscana Gp Sassendalen Gp Botneheia Fro, 175 m Sticky Keep Fm Kaosfjellet Mbr, 268 m Iskletten Mbr, 85 m Vardebukta Fm Siksaken Mbr, 68 m Selmaneset Mbr, 35 m Tempelfjorden Gp.

4.4.6

Wedel Jarlsberg Land, mid and southeast

The same strip of deformed Triassic strata continues parallel to the orogen. Sections were logged by Rozyicki (1959) at Passhatten and by M o r k & Worsley at Somovfjella and Tvittopane, both in mid Wedel Jarlsberg Land. Treskelen sections, north of inner Hornsund, have been available to many scientists in the Treskelodden promontory to the north of inner Hornsund. In mid Wedel Jarlsberg Land, the sequence from Rozycki (in Buchan e t al. 1965) follows. Kapp Toscana Gp, Rozicki c. 204 m Wilhelmoya Fm, c. 40 m (estimated) De Geerdalen Fro, c. 100 m

THE CENTRAL BASIN

Sassendalen Gp Botneheia Fm, 220m Sticky Keep Fm, ?83 m Vardebukta Fm, 65 m At Treskelen Kapp Toscana Gp, 150-160 m Wilhelmoya Fin, c. 23 m De Geerdalen Fro, c. 103 m Tschermakfjellet Fro, c. 34 Sassendalen Gp Botneheia Fro, 111 m or 105 m Sticky Keep Fin (85 m or 110 m) Vardebukta Fin (101 m or 80 m) Sticky Keep and Vardebukta Fms combined, 190 m

4.4.7

Sorkapp Land

Sorkapp Land contains interesting contrasts which may be summarised in four zones in all of which Sassendalen Group strata appear, it not being easy to ascertain whether or where Kapp Toscana rocks may occur. (i) In the eastern zone the Sassendalen Group rests on Tempelfjorden Group strata within the foldbelt as to the north. That is continuing the Treskelodden relationship to the SSE within the foldbelt. (ii) In the central zone relatively flatlying Sassendalen Group strata rest with sharp angular unconformity on deformed Precambrian to Early Paleozoic rocks. This zone has been referred to as the Hornsund High. (iii) In the west similarly flatlying strata rest with only minor discordance on similarly flatlying Billefjorden Group rocks. However this western zone did not escape Paleogene deformation because there are Klippen of relatively horizontal Mesozoic strata as illustrated in the Sorkapp Land map C13G (Winsnes et al. 1992). (iv) In Sorkappoya, the island south of Sorkapp Land Sassendalen Group strata are infolded in a steep syncline with Tempelfjorden Group rocks trending N W to N N W . If extended this fold belt would pass offshore west of Sorkapp Land as it parallels the West Spitsbergen Orogen. Zone (i) continues with that at Treskelen to the north with sections at Smalegga just south of Hornsund and at Austjokeltinden about 13 km south of Hornsund. Wilhelmoya Fm, c. 25 m at both localities De Geerdalen Fro, c. 40 m at Smelegga and 55 m at Ausjokeltinden Tschermakfjellet Fm( = Austjokelen Formation of Mork et al.) Sticky Keep Fm Vardebukta Fro. In zone (ii) two sections are available from Karentoppen and Kistefjellet

Kapp Toscana Gp, c. 60 m Wilhelmoya Fm at Kistefjellet, c. 35 m De Geerdalen Fin at Kistefjellet, c. 31 m Tschermakfjellet Fm at Kistefjellet, c. 16m Sassendalen Gp c. 100 m Botneheia Fm at Karentoppen, 65 m Kistefjellet 75 m Kistefjellet Fm (=Sticky Keep and part of Vardebukta) 50m at Karentoppen, 35 m at Kistefjellet. In zone (iii) No measured sections are recorded here. In zone (iv) in Sorkappoya the succession is upper strata lost to erosion Botneheia Fm, c. 60 m Sticky Keep Fro, c. 90 m Vardebukta Fro, c. 60 m Tempelfjorden Gp Kapp Starostin Fro.

4.4.8

Kongsfjorden

The coalfield at Ny-Alesund is described in Chapter 9. The Bottom Shale of Orvin (1934), beneath the coal-bearing Paleogene strata,

63

was correlated by Challinor (1967) with the Vardebukta Formation. This unit thins from 50 m at the SE of the coalfield to zero at the southwest which demonstrates the limit of Mesozoic strata of the Central Basin in that direction.

4.5

Biinsow Land Supergroup

Comprising Tempelfjorden, Gipsdalen and Billefjorden groups: Permian, Carboniferous, and latest Devonian. The cliff sections from Billefjorden through to Tempelfjorden provide excellent exposures of the whole Carboniferous through Permian succession (Fig. 4.10), and have become the type sections for central Spitsbergen, hence the Biinsow Land Supergroup. The sequence was deposited in the Billefjorden Trough, mainly situated to the east of the Billefjorden Fault zone, and an active basin from Tournaisian through Moscovian time. To the west of the fault zone lay the Nordfjorden Block/High, where sedimentary rocks of those ages are absent. Following Moscovian time, subsidence was regional and most formations are represented across both sides of the fault zone and throughout the central area. Early investigations on the succession focussed on the Billefjorden-Tempelfjorden region (Nathorst 1910). The first systematic description resulted from a measured study at the now classic Festningen section, located at the southern entrance to Isfjorden (Hoel & Orvin 1937, Fig. 4.1). Brief contemporary surveys were carried out and described by Frebold (1935) and Orvin (1940). In 1938 and from 1948 onwards many groups from Cambridge studied the exposures (for example: Gee, Harland & McWhae 1953; Forbes, Harland & Hughes 1958). Exploration by Amoseas (an industrial consortium, jointly with Cambridge University geologists in the 1960s and in consultation with Norsk Polarinstitutt, resulted in reclassification of the strata throughout Svalbard (Cutbill & Challinor 1965), using nomenclature in accordance with the N o r t h American Stratigraphic Code which was being widely adopted at that time. Several changes have been suggested since then, primarily to the Svenbreen and Nordenski61dbreen formations (Dallmann et al., SKS 1996). These and the scheme used here are shown in Fig. 4.11.

4.6

Tempelfjorden Group (Permian)

The Tempelfjorden Group in Spitsbergen comprises the Kapp Starostin Formation. It was defined by this and the Miseryfjellet Formation of Bjornoya.

4.6.1

Kapp Starostin Formation

The Kapp Starostin Formation is the main unit of the Tempelfjorden Group in central and western Spitsbergen. It consists of a thick siliceous sequence which is resistant to weathering, and hence is well exposed and a distinctive marker horizon throughout Spitsbergen, having softer Gipsdalen Group dolostones below and Triassic shales above. The type section is at Kapp Starostin (Festningen), Nordenski61d Land, where the formation is 380 m thick (Fig. 4.1). The formation mainly contains limestones, lutites, arenites and cherts, generally with sponge spicules. Sandstones are commonly cross-bedded, bioturbated and glauconite-bearing. The sequence is transgressive overall, with deposition occurring in a shallow shelf environment where shoals and reefs were present. An abundant fauna of brachiopods, bivalves, corals and others indicate a Kungurian-Ufimian age.

64

CHAPTER 4

Fig. 4.10. Geological map of Bansow Land showing the distribution of Permo-Carboniferous formations (Bfinsow Land Supergroup), adapted with permission from SKS proposals for Lithostratigraphical Nomenclature of the Upper Paleozoic rocks of SvaIbard, Part I (Dallmann et al. 1996, fig. 3d). White areas indicate fjords or (on land) supergroups younger (? Nordenski61d Land - mainly Mesozoic) or older Devonian (Liefdebay Supergroup) to the NW or pre-Devonian Hecla Hoek Complex to the NE. Place names are selected for their relevance to stratigraphic nomenclature in this classic area of north-central Spitsbergen. Those given by numbers are as follows: (1) Birger Johnsonfjellet; (2) Brucebyen; (3) Cadellfjellet; (4) Campbellryggen; (5) Carronelva; (6) Citadellet; (7) Ebbadalen; (8) Finlayfjellet; (9) Fortet; (10) Gerritbreen; (11) Gerritelva; (12) Gipshuken; (13) Hoelbreen; (14) H ultberget; (15) Minkinbreen; (16) M umien; (17) Odellfjellet; (18) Pyefjellet; (19) Pyramiden; (20) Sporehogda; (21) Svenbreen; (22) Templet; (23) Terrierfjellet; (24) Trikolorfjellet; (25) Triungen; (26) Tyrrellfjellet; (27) Wordiekammen. Definition: The formation was defined by Cutbill & Challinor (1965) and is the exact equivalent of the Brachiopod Cherts of Gee et al. (1953; Fig. 4.11). It is exposed along the west coast and extensively across northern Spitsbergen to Nordaustlandet. Small outcrops have been described from Barentsoya (Klubov 1965) and Edgeoya (Pchelina 1977). lsopachs for the formation (Cutbill & Challinor 1965) show that deposition was in the large Central Basin with thickest sedimentation in western Nordenski61d Land where up to 450 m are preserved. There appears to be a secondary centre of deposition in the Tempelfjorden area, which may, however, be due to differential pre-Triassic erosion. The formation thins rapidly onto the Hornsund High in the south. This was a positive feature during deposition and a site of pre-Triassic erosion. Southwest of the Hornsund High, Late Permian sediments are preserved in a somewhat separate basin. The top of the formation is a distinctive marker horizon, with the resistant siliceous deposits of the Hovtinden Member lying below soft shales of Early Triassic age. The base is also distinct, defined as a disconformity, overlying the less resistant gypsums, dolostones and calcretes of the Gipshuken Formation. Through many areas of Svalbard, the base is marked by a sandy bioclastic limestone, the Voringen Member, which rests with a sharp and erosive contact on the underlying Gipshuken Formation. A distinctive fauna of large thick-shelled spiriferid brachiopods gave this unit the name 'Spirifer Limestone'. It represents the transgression of a barrier sequence over the restricted marine platform and sabkha facies of the underlying group (Aga et al. 1986) and marks a clear change in environment (see below). Lithologies: The formation shows a variable development of tithofacies but in general four main lithologies are recognized: limestones, lutites,

arenites and cherts. Silicification of the limestones, shales and siltstones is characteristic and there is a continuous gradation into pure cherts, which are estimated to constitute about 50% of the rock. Indeed a distinctive feature of later Permian sediments is their high silica content and cherty rocks are the dominant lithology of the Tempelfjorden Group. About 50% of the cherts are of a massive type interbedded with shales. These consist of massive layers of dark grey or black, very hard rock, composed of sponge spicules, quartz grains and fossil fragments in a brown groundmass of authigenic silica. The sponge spicules may be calcified on diagenesis, and their axial canals are commonly filled with glauconite or silica. The brown colour of the chalcedony cement is probably due to the presence of carbonaceous matter. Finely divided hydromicas are also present. Finely crystalline cherts, consisting mainly of brown chalcedony with minor terrigenous quartz 'dust' (<0.03mm), hydromicas and carbonates, also occur, commonly containing a high proportion of glauconite in the form of rounded grains approximately 0.15 m m in diameter. Some beds are almost pure spiculite, consisting of closely packed and cemented light brown, chalcedonic sponge spicules. Much of the so-called massive chert is calcareous, suggesting that it may be diagenetic, replacing carbonate. Limestones form a marginal facies and make up about 25% of the formation. They occur in the northeast in the Hovtinden Member and in the north and south in the Svenskeega Member, while the basal Voringen Member is composed entirely of a white, brachiopod-bryozoan coquina. The limestones are usually calcarenites/biosparites with silica and calcite cement. They are invariably highly fossiliferous, with abundant silicified brachiopods and bryozoans. Chert bands and nodules also occur, which commonly show replacement structures of the original limestones and this

THE CENTRAL BASIN

Gee, Harland & McWhae (1953) Forbes, Harland & Hughes (1958) co

Cutbill & Challinor (1965) Holliday & Cutbill (1972)

Upper

z ~

Hovtinden Mbr

Lower

n" ~

Svenskeegga Mbr

Limestone A

~

Voringen Mbr

..z

,,z

m

UPPER GYPSIFEROUS SERIES

KAPP STAROSTIN FM

~; n. ,,c_ F-,,"

SKS Recommendations (Dallmann et el., 1996) adopted here

Dallmann (1993) McCann & Dallmann (1995)

Johannessen & Steel (1992)

Middle

"'

65

,,2 KAPP STAROSTIN

FM

~o

~-Z

Ho~indeo Mbr

~

nLU~ w w--.

n" ~ ~

I--LE

nO-

I--LC

~

GIPSHUKEN FM

GIPSHUKEN F M

GIPSHUKEN F M

~ 3~ n. u.I--.

Svenskeegga Mbr Veringen Mbr GIPSHUKEN F M

o Zn

Limestone B Upper

z

~ u,~

Middle

P3

~ .~ --~

L. . . .

~VLL = (,9 ~

Black Crag

z QO w J'

z

z

~ uJ

Cadellf]ellet Mbr

~

z

ca ._j ~7

~

m

_~

70

70

Trikolor~elIet

Mbr O<

~ ~VU. =

Cadellfjeltet Mbr

i

z

I Teltf]ellet

I

Odellf]ellet Mbr Tdkolorf]eUetMbr "~

~ u.I

I Sandstone Mbr

Ebbaelva Mbr

I

BILLEFJORDEN SANDSTONES (CULM)

z Cadellfjellet Mbr

Tyrrellf]ellet Mbr

u~z ~ ~

Z

J

Cadellf]ellet Mbr

~: D

~ Fortet Mbr AnsuivikaMbr Carronelva Mbr

~ ~ _~ ~ ,,~ :; ,7?

Ferret Mbr Terrie~ellet Mbr Carronelva Mbr

~

OdellfJelletMbr

z

:~

,~ ~ ~ uJ

Trikolo~ellet Mbr

a< ~ ~

~ O

(~

z QQs m~'_J

Trikolorf]ellet Mbr

Ebbaelva Mbr

:~z

Hultberget Mbr ww~ > ~ ~=

Tyrretl~ellet Mbr

Mbr

Ebbaelva I Gerritelva Mbr

~" L~ ~ ~ ~ 3; ~

Minkinfjellet Mbr

Minkinf]ellet Mbr

LOWER GYPSIFEROUS SERIES

Tyrrell~ellet Mbr

z

7~

Passage Beds

(=Pyramiden Conglomerate)

TyrerrelfJellet Mbr

Hultberget Mbr

Sporhogda Mbr

Cl wZ 8 ~ m~ ~J ~>m

u~ z >" w

Hoelbreen Mbr

"~' ~'

~ ~ LL

Triungen Mbr

Sporhogda Mbr

HORBYEBREEN FM

w w ..~

Sporhegda Mbr

~ O ~ ~,

Hultberget Mbr

~ z ~.~.m un~- tu nm~

Hoetbreen Mbr Triungen Mbr

HULTBERGET FM

~

MUMIEN FM

O

u~z

~

>'ILl mwmu_

~

~ =

Birger Johnsont]ellet Mbr Sporhegda Mbr Heelbreen Mbr

z O

~_ Triungen Mbr

,

Fig. 4.11. Summary of the stratigraphic schemes for Central Spitsbergen since 1950. For earlier schemes see review in Cutbill & Challinor (1965).

process has resulted in the formation of massive calcareous cherts. These are bituminous on Edgeoya (Pchelina 1977) Fine- to coarse-grained quartz sandstones are less important (about 18% of the formation). They occur in a widespread littoral facies in the Hovtinden Member and also in the Svenskeega Member. They contain cross-bedding and are commonly calcareous and bioclastic, with calcite or silica cement and are usually greenish coloured owing to the presence of appreciable quantities of glauconite (up to 3%). Porosity is generally low. These bioclastic sands, common in the middle of the group over eastern areas of Spitsbergen, can be distinguished from the major 60 m thick clastic wedge which is only seen in northwestern areas uppermost in this formation. These latter sandstones are immature and commonly contain 10-30% glauconite. Heavy bioturbation has destroyed primary bedding features. Shales and siltstones showing little or no silicification make up only 7% of the formation, occurring as thin interbeds between the limestones on the margins of the basin. They are commonly calcareous and pass laterally into limestones or arenites in the upper part of the formation. Silicification generally increases towards the centre of the basin with a gradation into cherts. Division: Cutbill & Challinor (1965) defined three members within the formation in the main Triassic outcrop of the Central Basin (Fig. 4.11): the Hovtinden Member; the Svenskeega Member; and the Voringen Member. Russian workers distinguished a separate, arenaceous 'Selander Suite' (Selanderneset Mbr), lying unconfomably above the 'Starostin Suite' in the northern sections (Burov et el. 1965). The Selander Suite is probably equivalent to the sandstone-limestone facies of the Hovtinden Member (see below), which pass laterally into shales, siltstones and cherts in Oscar II Land.

Hovtinden Mbr. This member, 203m thick in the Festningen section is present from Hornsund to Nordaustlandet though it is made up of a variety of complexly interdigitating facies. In northeastern and southern outcrops of Spitsbergen, this member lies directly on the Gipshuken Formation, the Voringen Member facies being absent. It is transgressive in southern Spitsbergen, overlapping progressively older rocks southwards towards the Hornsund High. In general, it consists of a central basinal facies of finely crystalline cherts, shales and siltstones, with arenaceous rocks and carbonates to north and south at the basin margins. The shale-chert facies in some sections is split by a limestone horizon and in north and central Spitsbergen, cross-bedded sandstones and arenaceous cherts also appear.

Svenskeegga Mbr. This member, 156m thick in the Festningen section, shows a similar facies pattern. The top is marked by the Jemtlandryggen Beds, made up of a yellow-weathering silicified limestone containing a prolific brachiopod-bryozoan fauna which is a distinctive marker horizon. Silicification locally results in true chert. There is also a sandstone or lutite interbed. Below are the Tornefjellet Beds, cherts with rare lutites, occurring in the central part of the Isfjorden Basin and Nordaustlandet. They pass both laterally and vertically into a more or less silicified limestone facies known as the Garwoodtoppen Beds which are widely developed in northern and southern Spitsbergen. The limestones are dark grey, weathering yellow, and commonly cyclically interbedded with lutites. A 10m thick breccia is present 20 m above the top of the Voringen Member of Bjorndalen (Sassenfjorden). It consists of nodular orange cherts which are commonly bioturbated and form lenticular blocks a few metres across. Bedding varies from horizontal to contorted and overturned. The basal contact of the breccia is erosive and marked by a shaly band. Voringen Mbr. This consists of 22-39 m of distinctive, light-coloured, coarse fragmental limestone with silicified brachiopods and bryozoans. It occurs at the base of the Kapp Starostin Formation from Bellsund to St Jonsfjorden and Nordaustlandet but is absent south of Bellsund and from most of Oscar II Land and is replaced by calcareous sandstones in Ny Friesland and southwest Nordaustlandet. It is the Spirifer Limestone and Brachiopod Limestone of previous authors and 'Limestone A ' of Gee et el. (1953) and is a useful marker horizon. Coal fragments are present in the lower part south of Sassenfjorden and in Nordaustlandet (Lauritzen 1981); this is probably an indication of erosion of the top of the Gipshuken Formation, as coaly shales are present in the topmost Gipshuken Formation in Nordaustlandet. The basal contact is erosive in Bellsund also, with clasts of micrite from the underlying Gipshuken Formation, which is extensively bored. Elsewhere on Svalbard, the contact is poorly exposed, owing to the susceptibility of the Gipshuken Formation to erosion, but there is further evidence for a disconlbrmity in the phosphatic nodule beds found at the base of the formation on the south side of Sassenfjorden. These may have been eroded from the underlying strata. Some were associated with glauconitic sands, a combination characteristic of episodes of slow sedimentation/non-deposition.

PNaeontology and age: The formation contains an abundant fauna, predominantly of silicified brachiopods, but also of bryozoans, bivalves, corals, sponge spicules, echinoderms, gastropods and foraminifers. Trace fossils abound, with Zoophycos, Teichichnus and Chondrites.

66

CHAPTER 4

Szaniawski & Malkowski (1979) distinguished two time-equivalent fossil associations which represent different depths: the bioclastic limestone facies of near-shore, shallow water, high energy thicker-shelled species and an offshore, low-energy, deeper water fauna dominated by sponges, with more fragile brachiopods and bryozoans, which occurs in the siliceous rocks associated with in-situ glauconite and pyrite. The brachiopod fauna is broadly comparable with the later Early Permian and Late Permian assemblages of Russia (Tschernyschew 1898, 1902). However, many of the species have long time ranges and show considerable intraspecific variation which has caused confusion over correlation. Biernat & Birkenmajer (1981) found that at the base of the Kapp Starostin Formation in Torell Land, two brachiopod species were the same as those in SakmarianEarly Kungurian rocks of Inner Isfjorden. Many species are closely related to the Artinskian or Kungurian species of the Soviet Union, but several genera characteristic of Late Permian also occur (Gobbett 1963). Ustritskiy (1962) and Burov et al. (1965) distinguished two separate faunas, both belonging to the Ufimian stage, in the 'Starostin Suite' (= Svenskeega/Voringen Members) and 'Selander Suite' (= Hovtinden Member), the latter being distinguishedby the presence of Cancrinelloides and Sowerbyna. These assemblages have not yet been recognized throughout Spitsbergen. A Kungurian age has been confirmed for the lowerpart of the formation (Nysaether 1977; Ustritskiy 1979) and a Ufimian age is indicated by the foraminifera for the small Permian inliers of Edgeoya, which are of the glauconitic chert facies (Pchelina 1977). The upper part contains brachiopods which extend into the Kazanian stage (Ustritskiy 1979) and Ustritskiy assigned the 'Starostin' (= the Voringen and Svenskeegga Members) and 'Selander' (= the Hovtinden Member) 'Formations' to Boreal stages (Paykhoyian and Early Novozeml'ian) which correlate with the Kungurian-Ufimian and Kazanian-?basal Tatarian respectively. Conodont assemblages also confirm a Kungurian-Ufimian age as they correspond stratigraphically to the Late Leonardian/Early Roadian of the USA (Szaniawskij & Malkowski 1979). As the formation is transgressive, lithological boundaries must be diachronous until open-sea cherty facies occur everywhere, i.e. at the top of the formation (Malkowski 1982). There is a stratigraphic gap in the Hornsund region, where the Voringen and Svenskeegga Members of the Isfjorden area are absent.

4.7

Gipsdalen Group (Permian-Carboniferous)

Cutbill & Challinor (1965) originally defined the Gipsdalen Group within the Billefjorden area to contain the Gipshuken, Nordenski61dbreen and Ebbadalen formations. However, the Nordenski61dbreen F m has been replaced by the Wordiekammen and Minkinfjellet formations. Hence now the group comprises the Gipshuken, Wordiekammen, Minkinfjellet and Ebbadalen formations. These four formations are (Dallmann 1996 SKS) combined in two subgroups thus: Gipsdalen Group (Cutbill & Challinor, 1965) Dickson Land Subgroup (SKS) Gipshuken Formation (Cutbill & Challinor, 1965) Wordiekammen Formation (Gee et al. 1952, SKS) Campbellryggen Subgroup (Forbes, Harland & Hughes 1958, SKS) Minkinfjellet Formation (Cutbill & Challinor 1965) Ebbadalen Formation (Cutbill & Challinor 1965) The upper subgroup extends from Btinsow Land to the west across Dickson Land. The lower one is confined approximately to the Billefjorden Trough. As elsewhere in Svalbard, the base of the group is marked by the appearance of red-beds; these pass upwards through terrestrial and marine restricted-basin deposits into platform carbonate sequences with increasing quantities of evaporites. Deposition of the group and the underlying Billefjorden Group occurred initially within distinct, small basins defined by faults (Fig. 4.12). Later deposits, however, blanketed the entire region. Each formation is described below.

4.7.1 Gipshuken Formation (Dickson Land Subgroup) Present across much of western and central Spitsbergen, the Gipshuken Formation is 150-250m thick, consisting mainly of carbonates and evaporites with minor quantities of sandstone.

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Fig. 4.12. Schematic west-east stratigraphic profile showing lateral variations and structural controls on Carboniferous stratigraphy. Simplified, and modified with later SKS nomenclature, from Cutbill & Challinor (1965) with permission of Cambridge University Press.

THE CENTRAL BASIN R h y t h m i c d e p o s i t i o n a l sequences o f l i m e s t o n e / d o l o m i t e a n d g y p s u m / a n h y d r i t e are c o m m o n , especially in central exposures. T h e f o r m a t i o n was d e p o s i t e d in w a r m , shallow seas a n d tidal flats w i t h restricted c i r c u l a t i o n t h a t allowed high salinity to develop. In general, the evaporites, w h i c h represent arid l a g o o n a l , tidal flat a n d s u p r a - t i d a l s a b k h a deposits, are m a i n l y f o u n d in central Spitsbergen. E a s t w a r d s they are replaced by limestones a n d d o l o m i t e s . Fossils are scarce, b u t those t h a t are p r e s e n t indicate an A r t i n s k i a n age. Definition: These strata were included in the Cyathophyllum Limestone of early authors (Nathorst 1910), but were distinguished as a separate unit in the Billefjorden region by Gee et al. (1953), whose upper Gypsiferous Series is an exact equivalent. The formation was defined by Cutbill & Challinor (1965) in Billefjorden, where the formation is 210 m thick. Lauritzen (1981) proposed a hypostratotype for the formation at Trollfuglfjella on Dicksonfjorden, where the formation is exceptionally well exposed. It is thickest in western Isfjorden (up to 350 m), but over much of the outcrop, it is between 150 and 2 5 1 m . It thins northwards, nearer the Northern Block and southwards towards the Hornsund High (about 70 m at Drevbreen in Torell Land). in the Hornsund area it is absent, where the Kapp Starostin Formation lies disconformably on the Carboniferous Treskelodden Beds, which were formerly correlated with the Gipshuken Formation (Cutbill & Challinor 1965). The present outcrop of the formation is largely confined to two belts. Along the west coast of Spitsbergen, outcrop is sporadic and largely controlled by the structure of the West Spitsbergen Orogen. The strata in central Spitsbergen are mainly flat-lying and relatively well exposed. The formation also crops out in eastern Ny Friesland and Nordaustlandet, bordering Hinlopenstretet, and to the south on Bjornoya. It is present beneath the younger strata of central Spitsbergen. The upper boundary of the Gipshuken Formation is mapped at the base of the distinctive siliceous deposits of the Kapp Starostin Formation. Some erosion of the top of the Gipshuken Formation took place before deposition of the Kapp Starostin Formation in marginal areas, hence its absence in the south. The base of the Kapp Starostin Formation is a marker recognized throughout Spitsbergen. The lower boundary is transitional with the underlying Wordiekammen Formation, where the formation is preserved from pre-Kungurian erosion. The base is therefore defined by the appearance of gypsum, where present, or by the widespread and distinctive Kloten Breccia Member. Where both are absent, the top of the underlying Tyrrellfjellet Member is marked by the distinctive cliff-forming 'Limestone B' (Finlayfjellet Beds). Lithologies: The formation is a major regressive sequence characterised by highly variable lithologies, dominated by carbonates and evaporites, of which approximately 60% are carbonates, 30% gypsum and 10% arenites. In the central part of the Isfjorden Basin, rhythmic deposition of dolostone/limestone and gypsum/anhydrite continued throughout the formation. The central zone of sulphate deposition is surrounded by a broad zone in which only the dolomite/limestone part of the evaporite cycle was deposited. These rocks consist predominantly of algal-laminated, locally gypsiferous, silt-textured dolostone (about 35% of the formation) formed by the trapping of lime-mud by mucilagenous green algae. Thin interbeds of silt-textured limestone occur locally. Some of the dolostones within the anhydrite zones of the lower part of the sequence in Torell Land are rich in quartz sand. Dolomitised ooids and pelloids occur with micritic dolomites in Dickson Land and Torell Land, where anhydrite nodules and cement are common in the anhydritic zones of the lower part. The gypsum/anhydrite horizons are locally massive and form relatively thick, continuous beds parallel or sub-parallel to the bedding. Elsewhere, the sulphate is laminated or finely interbanded with dolostone or rare limestone. It may also occur as nodules up to 1 m in diameter, separate crystals or infillings of cracks, fissures and stylolites (Lauritzen 1977). The gypsiferous deposits pass laterally into continuous dolostone. Laminated shales occur in units up to 2 m thick between the anhydrite beds. About 30 rhythms with anhydrite have been recognised in the Dicksonfjorden area by Lauritzen (1981), varying in thickness from 0.6 to about 9.5m. Each rhythm starts with a carbonate unit, which may contain ripples and cross-bedding or oolitic beds, followed by carbonates with anhydrite nodules, ending with chicken-wire anhydrite and commonly terminated upwards by a sharp, erosive contact with the base of the next cycle. Karstic surfaces have been observed in the anhydrite (Lauritzen 1983). Dolomitization is almost complete in this cyclic succession and is thought to be early diagenetic. Locally, in west Spitsbergen, dedolomitisa-

67

tion is well developed, with corroded clasts of yellow-weathering dolomicrite in a grey calcite matrix passing into uniformly grey calcitised rock. In the lower part of the formation, is a widespread group of carbonate breccias up to 30 m thick which make up about 13% of the formation. Two distinct types can be recognized- a hard, massive variety and a soft, porous, cellular type. The massive breccia is of rather limited occurrence in the northwest of the outcrop area, where it forms a resistant marker horizon. It consists of a complex of grey, laminated, silt-textured dolostone or limestone blocks, up to several metres in diameter, in a dolostone or limestone matrix. The dolostone weathers yellow and the limestone grey, but the unit is very hard and individual fragments are difficult to identify on unweathered surfaces. The fragments commonly show contorted lamination, indicating slumping prior to brecciation. In some cases dolomite is seen replacing calcite across fragment boundaries, whilst others show a sharp contact. Patches of dolomite crystals give a mottled effect in places. The cellular breccia has a wider distribution, and consists of brecciated silttextured limestone and dolostone. The interstices between the individual fragments may be filled by dolomite or calcite cement and calcite veining commonly gives a honeycomb structure. In places cement may be completely or partially absent, giving the rock a high porosity and permeability. Its cellular appearance is due to the variable weathering properties of calcite and dolomite. The breccias appear to pass laterally by way of sandy limestones and dolomites into arenites. In Bellsund, minor breccias are present in the upper parts of the Gipshuken Formation, where laminated dolomicrites occur with thin sandy interbeds, the relationships of which suggest that brecciation occurred prior to full lithification of the sand. Fossiliferous limestones, consisting of calcilutite and calcarenite, interdigitate with the dolostones in the upper part of the formation, making up about 8% of the sequence. In Torell Land they form the upper third of the formation and show a general increase in coarseness towards the top from dark grey micrites to grey-black biosparites. The darkening in the biosparites probably reflects increasing contents of organic matter. Fine laminations and small-scale ripple-marks and convolute bedding have been recorded (Nysaether 1977). Fossils are not common, but brachiopods do occur. Division: Gipshuken Formation deposits show a variation in facies, but only the distinctive breccias have been defined as members where they appear (see below). In Spitsbergen, in a general way, the sequence can be divided into: (5) The upper dolostone-limestone zone consisting of interdigitating dolostones and limestones. In Torell Land there is only limestone. (4) The upper gypsum zone comprising the evaporite deposits occurring in the centre of the basin, particularly on the west coast. North of Isfjorden, there are only nodules and thin beds of evaporites in a predominantly dolomicrite sequence. (3) The Kloten Breccia Mbr (Cutbill & Challinor 1965) containing the various types of limestone/dolostone breccia described above. It forms a conspicuous marker horizon 88 m thick in the type section at Scheteligfjellet in the northeast of Spitsbergen and similar breccias occur eastwards to Tempelfjorden and also in Ny Friesland and Nordaustlandet. The latter outcrop was named the Zeipelodden Mbr by Lauritzen (1981). (2) The lower dolostone zone consisting of dolostones transitional between the Kloten Breccia Member and the lower gypsum zone below. It is only recognisable in the area of northwest Spitsbergen (Colletthogda) where true brecciation has not taken place, but contortion and slumping has occurred. (1) The lower gypsum zone consisting of the evaporites occurring in the lower part of the formation, mainly in the Billefjorden and Nordfjorden regions. The zone is rather restricted in western Spitsbergen. The Zeipelodden Mbr is 8 m thick and contains a mixture of lithologies, limestone breccias occurring together with finely laminated algal limestones, one passing into the other. Irregularly bedded horizons are weathered into distinctive caverns up to I m high. Hemispheroids of algal build-ups 2-3 m across, algal mats and crusts have been identified. A mixture of white chert and calcite is found within some of the hollows of the rock. The rocks are highly porous and dominantly calcitic, with clear evidence of dedolomitisation. This unit is, however, best considered in Chapter 5. Palaeontology and age: The bulk of the Gipshuken Formation appears to be unfossiliferous. Dolomitization has destroyed much of the evidence of fauna but algal lamination is extremely common in the micrites, caused by mucilaginous blue-green algae (Lauritzen 1981). Another prominent feature observed in thin-sections from the upper part of the succession (Lauritzen 1981) is Microeodium which has been described from palaeosols (Klappa 1978).

68

CHAPTER 4

Fossiliferous beds do occur in various places. Gastropods, especially bellerophontids, and bivalves have been recorded by Lauritzen in the Dicksonfjorden area as well as a little bioturbation. In addition, CSE 1985 found echinoids, crinoids and bryozoa in Nordaustlandet. A few productid brachiopods have been found in the upper part of the formation in Nordaustlandet, Kopernikusfjellet and at Trygghamna which indicate a correlation with the Hambergfjellet Formation of Bjornoya; (the latter contains Artinskian fusulinids). Cancrinella koninkiana which was found in the Gipshuken Formation by Ustritskiy (Burov et al. 1965) is typical of the Artinskian stage and Sossipatrova (1967) discovered the Frondieularia multicamerata assemblage in the middle of the formation in Bunsow Land and correlated it with the Artinskian deposits of the Urals and north Timan.

4.7.2

Wordiekammen Formation (Diekson Land Subgroup)

T h e W o r d i e k a m m e n L i m e s t o n e o f G e e et al. (1953) was redefined (SKS, D a l l m a n n et al. 1996) to take in the u p p e r t w o m e m b e r s (Tyrrellfjellet a n d Cadellfjellet) o f the N o r d e n s k i t l d b r e e n F o r m a tion o f Cutbill & C h a l l i n o r (1965). W i t h the G i p s h u k e n F o r m a t i o n it c o m p r i s e s the D i c k s o n L a n d S u b g r o u p , the characteristic o f w h i c h is a relatively u n i f o r m s p r e a d o f facies t h r o u g h o u t m o s t o f Spitsbergen. In this respect the D i c k s o n L a n d S u b g r o u p contrasts w i t h the u n d e r l y i n g C a m p b e l l r y g g e n S u b g r o u p w h i c h is s e p a r a t e d into distinct basins.

Tyrrellfjellet Member is a widely d e v e l o p e d c a r b o n a t e sequence o f Early P e r m i a n ( A s s e l i a n - S a k m a r i a n ) age, o c c u r r i n g at the t o p o f the o t h e r w i s e C a r b o n i f e r o u s W o r d i e k a m m e n F o r m a t i o n . T h e type section is at Tyrrellfjellet, Billefjorden, w h e r e it is 1 6 0 m thick; elsewhere its thickness is variable f r o m 1 0 0 - 1 6 0 m . It c o n t a i n s limestone, d o l o s t o n e a n d arenites, with local gypsiferous units, widely d e v e l o p e d cherts, a n d P a l e o a p l y s i n a b i o h e r m a l m o u n d s . T h e f o r m a t i o n was d e p o s i t e d in l a g o o n a l a n d o p e n m a r i n e basin e n v i r o n m e n t s . It is highly fossiliferous with a varied fauna.

Definition: The member was defined by Cutbill & Challinor (1965). These limestones form the middle part of the Cyathophyllum Limestone of early workers (Nathorst, 1910); they are equivalent to the Mid- and Upper Wordiekammen Limestones described by Gee, Harland & McWhae (1953) in the Billefjorden area. It is thickest in the west (243 m at Orustdalen); over most of Spitsbergen it is 100 150m thick. The formation thickens slightly across the Billefjorden Trough, and thins slowly to the east across Ny Friesland. In Nordaustlandet it is replaced by the similar Idunfjellet Member and in southern Spitsbergen by the Treskelodden and Reinodden formations. The formation lies conformably beneath the dolostones and evaporites of the Gipshuken Formation. The highest beds of the Tyrrellfjellet Formation are transitional, containing dolostones, but the boundary can be mapped by the distinctive facies attributed to the Gipshuken Formation (see above) and by the occurrence of the distinctive cliff-forming 'Limestone B' at the top in the Billefjorden area (see below). The lower boundary of the formation represents a widespread marine transgression in Spitsbergen, which approximates the initial Permian boundary. In the west and south, the formation rests on various Carboniferous horizons, but throughout the northern outcrop it overlies Late Carboniferous shelf carbonates. However, near the base, the Brucebyen Beds form a marker horizon which can be recognised over much of the area. A thin sandy horizon, locally conglomeratic, occurs a few metres below the Brucebyen Beds which marks the basal disconformity or non-sequence in this area and can be recognized when outcrop is sufficiently good. Lithologies: The Tyrrellfjellet Member is made up of limestones (c. 85%), dolomites (c. 5%) and arenites (c. 10%). Fossiliferous relatively shallow-water shelf limestones, consisting of calc-lutite and calcarenite with subordinate dolostone occur over large areas of Spitsbergen in the lower part of the formation. They contain abundant corals, brachiopods and fusulinids. Similar shelf carbonates occur in the upper part of the formation, but are more commonly dolomitic, much less fossiliferous and pass laterally into dolostones. Close examination of the sequence has revealed the presence in the lower part of the sequence of biohermal structures (Skaug et al. 1982). The bioherm horizons are separated by fusulinid-rich wackestones and packstones which are dolomitized or bituminous as in the Brucebyen Beds (see below), which is a bituminous fusuline coquina.

Intraformational conglomerates occur locally above the bioherms, as do desiccation cracks. The bioherms are up to 2500 m 2 in area and their original calcite mudstone is dolomitized to some extent. Examination of thin sections (CSE 1985) revealed two types of dolostones, fine and coarse. The finer dolomicrite variety suggests early 'penecontemporaneous' replacement, possibly by evaporitively modified brines, since these solutions tend to have a considerable potential to dolomitize and hence are likely to alter calcium carbonate very rapidly, producing fine-grained dolomite; the presence of nodular gypsum locally provides evidence of an evaporative environment. The coarse dolostone is probably late-diagenetic as high-magnesium calcite crinoid and echinoid fragments, which should have been preferentially altered have not been dolomitized, suggesting that they were stabilized to low-magnesium calcite prior to replacement. All bioherms show good primary growth-framework porosity which is enhanced by secondary porosity associated with the dissolution of skeletal grains during dolomitization. In places porosity has been reduced by the crystallization of gypsum in pore spaces. Dolostones occur mainly in the upper part of the formation and largely in the northwestern outcrop area. They consist of very thinly bedded or laminated silt-textured dolostones with rare limestones, locally gypsiferous, and pass laterally into shelf carbonates. In the dolostone interbeds of the lower part, pseudomorphs after ?evaporite crystals have been noted, in places filled by length-slow chalcedony, calcite or dolomite; others are darkstained with a high kerogen and pyrite concentration (Skaug et al. 1982). Chert, generally occurring as nodules or rarely as bands, is locally widely developed, though not on the scale of the Tempelfjorden Group. The nodules, preserving bioclastic remains, are found within secondary dolostones in which sedimentary fabric has otherwise been destroyed. Sedimentary laminae are commonly deformed around the chert nodules, pointing to early diagenetic silicification, prior to complete compaction. Stylolites, which skirt around the nodules, support the latter observation. Calcareous sandstones, locally silty, are found as thin layers or lenses in the shelf limestones. They occur in the north, and in Ny Friesland where they are fine to medium-grained and interbedded with limestones. Crossbedding indicates currents from the southeast. On the Hornsund High, the limestones pass laterally into the commonly calcareous sandstones of the Hyrnefjellet Formation (Chapter 10). At the base of the formation is a thin sandstone horizon with a locally developed basal conglomerate. Division: The upper part consists of carbonates, commonly dolomitic, occurring throughout much of northern and eastern Spitsbergen. To the east and north they pass laterally into calcareous sandstones, and in the northwest into the dolomitic Ki~rfjellet Beds. Defined by Cutbill & Challinor (1965), the Kiaerfjellet Beds are thinly-bedded soft dolostones 96m thick developed at the top of the Tyrrellfjellet Member in the northwest of Spitsbergen. In eastern Svalbard and in the type section on Tyrrellfjellet, there is a cliff-forming calc-lutite forming the upper part of the member named 'Limestone B' by Gee et al. (1953, fig. 4.7) and Finlayfjellet Bed (SKS, Dallmann et al. 1996). The limestone is a 38 m thick cliff-forming micrite which makes a useful marker at the top of the Tyrrellfjellet Member in Btinsow Land. The lower part of the Tyrrellfjellet Member on Spitsbergen consists of fusuline limestones, locally biohermal, underlain by the bituminous micrudite Brncebyen Beds which are themselves underlain by up to 10m of dolostone, again locally biohermal, then a thin basal sandstone horizon with a locally developed conglomerate. The Brucebyen Beds, (Cutbill & Challinor 1965), consist of 2-20 m of distinct dark grey bituminous fusuline limestone coquina or biomicrite with a gradational top and base, 5-10m above the base of the Tyrrellfjellet Member. The fusulinids lack wall structures and their body chambers are infilled with dolomite. This is an excellent marker horizon over large areas of Spitsbergen. These beds occur within or below the palaeoaplysinid biohermal structures. In some areas eg. Gerardfjella, the carbonates are completely replaced by dolomicrite; nodular gypsum is also present here. Palaeontology and age: The formation is highly fossiliferous, with brachiopods, corals, bryozoans, echinoderms, bivalves, gastropods, sponges and foraminifera, of which fusulinids are particularly important as zone fossils where they occur, which is in the lower part only. Plant remains including algae, Microcodium and rootlets are also found. Skaug et al. (1982) described localised bioherms with Palaeoaplysina which are developed over the Billefjorden Fault Zone and elsewhere. There may be an algal contribution to the development of these structures. They are generally discoid and made up of subparallel to undulating plates up to 40 cm across which

THE CENTRAL BASIN may be closely packed or may enclose and bind pockets of bioclastic mudstone or wackestone containing all the above-mentioned fossils. They consist of small isolated dome structures up to 6 m high, tabular units up to 15m high, or offlapping sequences with one bioherm draping over the adjacent one to form structures up to 2500 m 2 in area. Their basal surfaces are sharp and usually planar to slightly undulating; most tops are sharply defined but some are gradational to overlying bedded carbonates. Studies of the abundant faunas found in the Tyrrellfjellet Member limestones by Forbes et al. (1958), Forbes (1960), Gobbett (1964), Cutbill & Challinor (1965) and Cutbill (1968) indicate an Early Permian age for these rocks. Gobbett distinguished two distinct brachiopod faunas in the Gipsdalen Group. The younger fauna, found in both the Tyrrellfjellet Member and also the Hambergfjellet Member on Bjornoya indicates a correlation with the Early Permian (Asselian/Sakmarian) faunas of Russia. Studies of fusulinids (Ross 1965; Cutbill & Challinor 1965) are in agreement with these ages. The lower part of the Tyrrellfjellet Member contains Asselian species of the Schwagerina anderssoni zone which compares with the Lower Wolfcampian fauna of Ross (1963) in North America. A poorly known assemblage from the middle of the formation belongs to the Monodiexodina zone which compares with the Early Sakmarian faunas of the Urals and Upper Wolfcampian faunas of North America (Ross 1963). The small foraminifers have received less study and stratigraphic conclusions based on them are less certain. Sosipatrova (1967) described a foraminiferal assemblage from the Tyrrellfjellet Member which helps to confirm the Asselia~Sakmarian age since Protonodosaria rauserae and Nodosaria parva are foraminifers diagnostic of the Boreal Sezymian stage (Asselian-Sakmarian). The Brucebyen Beds have a nearly identical fauna to the lower fusulinid-rich limestone within the palaeoaplysinid biohermal dolomites of the Kapp Dun6r Formation of Bjornoya.

Cadellfjellet, Kapitol and Morebreen Members.

The Cadellfjellet

M e m b e r , with equivalent Kapitol and Morebreen m e m b e r s to the west, consists o f a sequence o f late C a r b o n i f e r o u s limestones (locally dolomitic), occurring widely across Oscar II L a n d , James I Land, D i c k s o n L a n d and Btinsow Land. It reaches 200 m thickness in the Billefjorden area. The c a r b o n a t e s locally c o n t a i n gypsiferous layers and chert nodules. C a l c a r e o u s sandstones a n d s a n d y limestones f o r m a m i n o r p a r t o f the sequence. T h e f o r m a t i o n represents a stable m a r i n e shelf e n v i r o n m e n t , with sabkas present locally in coastal areas. F a u n a are sparse, but fusulinids suggest a late C a r b o n i f e r o u s ( K a s i m o v i a n - G z e l i a n ) age, possibly extending back to M o s c o v i a n .

Definition: Below the Tyrrellfjellet Member in central and western Spitsbergen lies a sequence of mainly limestones and dolostones. They are thickest in the Billefjorden Trough, where the type section lies; and thin westwards onto the Nordfjorden Block (the Kapitol Member), and then thicken again slightly into the St Jonsfjorden Trough in Oscar II Land (the Morebreen Member). The third is described in Chapter 9; the first two are described below. To the east in Ny Friesland, it is much thinner (40 m) and more arenaceous (see Chapter 7). The Cadellfjellet Formation is the lowest unit that can be identified across the Nordfjorden Block; below it deposits are restricted to the isolated basins of the St. Jonsfjorden and Billefjorden troughs. The Cadellfjellet strata were included in the Cyathophyllum Limestone of early workers and are equivalent to all but the uppermost part of the Lower Wordiekammen Limestones of Forbes, Harland & Hughes (1958). The unit was defined as a member within the Billefjorden area only, by Cutbill & Challinor (1965), equivalent to and laterally continuous with the Kapitol Member. (Nordfjorden area) and Morebreen Member. The top of the Cadellfjellet Member is marked by the widespread disconformity at the base of the Permian Tyrretlfjellet Member, which can be difficult to recognise in the carbonate sequence of this region. However, there is a thin, sandy, locally conglomeratic horizon at the bottom of the Tyrrellfjellet Member, and a few metres below, the distinctive bituminous fusulinid limestone coquina of the Brucebyen Beds In the Billefjorden Trough, the lower boundary is taken at the base of a black limestone horizon known as the 'Black Crag' (see below). Everywhere, the base is also defined by the appearance of Waeringella usvae zone fusulinids. The Kapitol Member is only about 50m thick thinning westwards across the East Dickson Land Axis from the 200m Cadellfjellet Member east of the Billefjorden Fault Zone.

69

Over the Nordfjorden Block, the Kapitol Member replaces the Cadellfjellet Member. The lower boundary is a strongly developed unconformity, below which Devonian sandstones occur. To the west of the Billefjorden Fault zone at Kapitol (type section of the member), the Cadellfjellet Member passes almost entirely into carbonates with very little horizontal or vertical variation. Limestones, mainly biomicrites and biosparites, form 70% of the sequence there. They are rather pure, grey and buff-weathering, with a high biogenic constituent. They commonly have a siliceous cement and horizons with abundant chert nodules occur. The remainder of the sequence is formed by primary dolomite as in the Mathewbreen Beds, which are largely uninterrupted in the east of the area but are interbedded with the limestones in the west. The Morebreen Mbr further west in the St Johnsfjorden Trough is thicker but not so easy to distinguish from the rest of the Wordiekammen Formation. It is described in Chapter 9.

Litbologies: The type section of the member is on Cadellfjellet, where it is thickest. There it consists predominantly (95%) of limestones, locally dolomitic, and rare gypsiferous layers. The limestones are grey, mainly massive micrites, becoming coarser-grained to the east. Calcareous sandstones and sandy limestones constitute the remaining 5% of the sequence. In the northeast (Ny Friesland), they occur in the upper part of the formation, commonly interbedded with gypsum layers and sedimentary breccias. In places, the lower 10-20 m of the basal limestones are brecciated. This was originally thought to be a result of collapse, following solution of evaporites in the underlying Minkinfjellet Formation (McWhae 1953). However, small-scale thrusts have also been observed forming an imbricated structure in the underlying beds, and suggesting at least a tectonic component. In southeast James I Land there is a thin conglomerate at the basal unconformity (Bates & Schwarzacher 1958). The clasts are generally small (5-10mm) and consist mainly of Devonian quartz sandstones and older quartzites in a reddish sandy matrix. In exposure east of Billefjorden, a distinctive, dark-grey micritic bed over 50 m thick occurs at the base (the 'Black Crag'; see below). Division: The Cadellfjellet Member is subdivided regionally into three as described above, with the type section in the Billefjorden area in the east, becoming the Kapitol Member in the central region and the Morebreen Member in the west. However, the main lithological subdivisions are the 'Beds' originally defined by Cutbill & Challinor (1965) - the Mathewbreen, Gerritbreen and Jotunfonna beds. The Mathewbreen Beds comprise the dolomitic limestones and dolomites of the formation. They are 34 m thick on Cadellfjeltet, but pass eastwards into arenites. In eastern Dickson Land they are up to 39 m thick, and occur as a thin outlier further west. They contain the Rugofusulina arctica zone fusulinid assemblage. They are not known west of Dickson Land. The distribution of these beds indicates some slight erosion at their top (prior to the Permian transgression) and in the west, the base is slightly unconformable on the underlying Gerritbreen Beds which have undergone some erosion (see below). The Gerritbreen Beds are limestones, mainly massive micrites and sparites, with a Waeringella usvae zone fusulinid assemblage. The beds occur right across the Nordfjorden Block where they are 30-50 m thick, with a marked thinning over the East Dickson Land Axis. A slight unconformity occurs at the top where the upper part of the W. usvae zone is locally absent and at the base where the underlying Jotunfonna Beds are also locally missing. In the east at Cadellfjellet they are 67 m thick. The Jotnnfonna Beds are grey bedded limestones and interbedded buff dolomites, with a Wedekindellina zone fusulinid fauna. A thin basal conglomerate occurs locally. On Kolosseum, the bottom 5-10m contain a Profusulinella zone fauna and are the oldest Middle Carboniferous beds so far found on the Nordfjorden Block. The beds are 50 m thick on the west side of Billefjorden, 30-50 m thick across the Nordfjorden Block, but are locally absent along the East Dickson Land Axis. They are not recognised on the east side of Billefjorden. The 'Black Crag' is a distinctive bed of massive dark grey micrite, over 50 m thick, found in the Adolfbukta region of Billefjorden. The lower 10-20m are commonly brecciated and it forms an excellent marker horizon in that area (Gee et al. 1953), but elsewhere it is much coarser-grained and cannot be distinguished from the rest of the formation. The Pyefjellet Beds occur to the east and in part replace the Black Crag (Pickard et al. 1996). Palaeontology and age: The formation contains a rather sparse fauna, of which brachiopods, molluscs, corals, trilobites, bryozoans and fusulines have

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been described (Gobbett 1964; Forbes et al. 1958; Cutbill 1968). No macrofauna was recorded across the Nordfjorden Block except for a few brachiopods reported by Gobbett (1964): Krotovia? sp.; ?Chaoiella cf. taiyuanfuensis (Chao); Choristites sp.; and Spiriferina sp. These may, however, come from the overlying formation, although fossils do undoubtedly occur in the Cadellfjellet Formation there. The coral, bryozoan and brachiopod faunas in eastern areas imply a Late Carboniferous age, and the strata were first assigned to the Triticites zone (Forbes et al. 1958). The fusulinids are abundant, Cutbill's work on them defined two zones. The upper Rugofusulina arctica zone correlates with the latest Carboniferous (Gzelian) of the Russian Platform, and is found in the Mathewbreen Beds. The lower Waeringella usvae zone correlates with the Gzelian and Kasimovian stages and occurs in the Gerritbreen Beds. At Kolosseum, the basal 5-10 m contain a Profusulinella zone (Early Moscovian) fauna, and the 'Black Crag' contains Wedekindellina sp. and the coral Bothrophyllum conicum, both of which indicate a latest Moscovian age (Wedekindellina zone). Thus the formation has a Kasimovian-Gzelian age, except for these local Moscovian units.

4.7.3

Minkinfjellet Formation (Campbellryggen Subgroup)

T h e Minkinfjellet Formation is p r e s e n t in the Billefjorden area only. It is a u n i t with steep lateral a n d vertical facies variations. It has a thickness o f 3 0 0 - 4 0 0 m with its m a x i m u m a d j a c e n t to the Billef j o r d e n F a u l t zone (Fig. 4.12) w h i c h c o n t r o l l e d d e p o s i t i o n . It consists m a i n l y o f c a r b o n a t e s , s a n d s t o n e s a n d evaporites, with red c o n g l o m e r a t e s in places. D e p o s i t i o n o c c u r r e d d u r i n g M o s c o v i a n time, p r o b a b l y in fluvial fans b u i l d i n g o u t into a m a r i n e basin. S a b k h a s a n d l a g o o n s d e v e l o p e d o n the fan b u t were subject to r a p i d base-level changes.

Definition: The Minkinfjellet Fm consists of a variable sequence of carbonates, sandstones and evaporites which occur mainly within the Billefjorden Trough, below the massive limestones of the Cadellfjellet Member. The sequence was first described by Scottish Spitsbergen Syndicate geologists, who introduced the term 'Passage Beds' in unpublished reports (Tyrrell 1919; Wordie 1919). Gee, Harland & McWhae (1953) gave further stratigraphic details, including the strata in the Campbellryggen Group. The unit was defined as a member within the Nordenski61dbreen Fm by Cutbill & Challinor (1965) and raised in rank by Dallmann (1993). It is thickest (300-400m) within the Billefjorden Trough adjacent to the Billefjorden Fault Zone, becoming thinner to the southeast. The Jotunfonna Beds at the base of the Cadellfjellet Formation (see above) occur on the west side of Billefjorden interleaved with the formation, but have not been identified to the east. The upper boundary is conformable and is marked in the Adolfbukta area by the overlying 'Black Crag' of the Cadellfjellet Mbr (see above). Elsewhere the top is marked only by the appearance of W. usvae zone fusulinids in the overlying strata. The base is apparently conformable within the trough, at the base of the Carronelva Beds, although this contact is probably disconformable (Dallmann 1993), as in the eastern area those beds overlap the Ebbadalen Formation and rest unconformably on pre-Devonian basement. On the western edge of the Billefjorden Trough, the formation overlaps the Billefjorden Fault zone and lies with distinct unconformity on various horizons of the Billefjorden Group. The formation is variable in thickness from 50m to 350m (Dallmann 1993). Lithologies: The type section is at Minkinfjellet. The formation is characterized by facies variation. It is dominated by carbonates, with dolostone, limestone, sandy limestone, marly limestone, limestone conglomerate and limestone breccias present. Coarse clastic rocks, generally yellowish or greenish in colour, are interbedded with the carbonates in places, as are thin beds of gypsum which also lines vugs in limestones. Limestone/dolostone breccias occur in the middle of the formation. Lateral variability is common within the formation. In places, grey, fossiliferous limestones (biomicrites and biosparites) are commonly interbedded with dolostones. In eastern Ny Friesland, the limestones become arenaceous and pass laterally into calcareous sandstones. Buff-coloured, micritic dolostones occur associated with evaporites and pass eastwards into limestones. A laterally restricted gypsum-anhydrite facies occurs in the central part of the trough. The evaporites are interbedded with dolostones which they pass into eastwards. To the west, towards the Billefjorden Fault Zone, they pass into clastic rocks.

Immediately adjacent to the fault zone, thick red and variegated conglomerates and sandstones occur in considerable thicknesses, comprising the whole formation. The red colouration may in part be secondary as the conglomerates are commonly derived from Devonian red-beds to the west. Division: In view of the lateral facies variation, widespread lithostratigraphic subdivision and correlation of the formation is difficult. Cutbill & Challinor (1965) originally recognized four u n i t s - the Carronelva, Elsabreen, Pyramiden and Anservika beds. However, Dallmann (1993), after Norsk Polarinstitutt remapping of the area, thought that the Pyramiden Beds and Elsabreen Beds were in fact the same unit. Furthermore, he thought that they are the lateral continuation of the Ebbadalen Formation to the south. He retained the Carronelva and Anservika beds but upgraded them to member status, and introduced a new unit, the Fortet Mbr, to the formation. The Anservika beds were indeed the equivalent of the Terrierfjellet beds (SKS). The Carronelva Mbr forms the lower part of the formation in central and northern areas. It is 41 m thick at its type locality, increasing to over 100 m in Ebbadalen and Ragnardalen. The base of the member is normally coarsegrained, either in the form of red conglomerates and other clastic lithologies or yellowish polymict conglomerates and sandstones. Yellowish sandstones continue through the middle of the member and are sulphurous in places. The upper strata consist of shales, marls, limestones and sandy limestones with some gypsum vugs. The member interfingers with the Anservika Mbr in its upper levels, and is overlain by either carbonates of that member or by breccias of the Fortet Member. The Terrierfjellet Mbr: The member is mainly exposed in eastern and southern parts of the Billefjorden Trough, but it is also present in the upper levels of the formation in central and northern areas. It consists of limestones and dolostones, interbedded with minor marls and marly limestones. Flint concretions and layers occur in the west of the outcrop, as also do rare gypsum layers. The thickness of the member varies from 33 m thick at the type section to 250-300 m in the central part of the outcrop. The Fortet Mbr: This member was defned by Dallmann (1993) for the intraformational carbonate breccias and conglomerates that are abundant in the upper part of the formation around the head of Billefjorden. The rocks overlie or replace (in the north) the carbonates of the Anservika Member. The breccias are probably of both in-situ brecciation and transported origin; grain- and matrix-supported varieties occur, with unsorted angular clasts up to 10cm in diameter. Dallmann estimated the member to be thickest at its type locality (approx. 240m).

Palaeontology and age: Limestones from the formation contain a marine fauna of which brachiopods, bivalves, corals and foraminifera have been described. The brachiopod assemblage compares with that of the Middle Carboniferous of the Moscow Basin (Gobbett 1964) and Cutbill's (CSE) Wedekindellina and Profusulinella zones are represented which correlate with the Moscovian stage. Crinoids were reported by Dallmann (1993).

4.7.4

Ebbadalen Formation (Campbellryggen Subgroup)

T h e E b b a d a l e n F o r m a t i o n is o n e o f the best k n o w n lithostratig r a p h i c units o f Svalbard. Like overlying units its d e p o s i t i o n was c o n t r o l l e d by its p r o x i m i t y to the Billefjorden F a u l t zone; it is t h e r e f o r e also laterally variable with wedges t h i n n i n g a w a y f r o m the fault in a h a l f graben. It is c h a r a c t e r i s e d by alluvial fan red-beds at the base a n d a d j a c e n t to the fault, which die o u t a w a y f r o m it a n d pass into two m e m b e r s . In the u p p e r p a r t o f the m a i n basin sequence are c a r b o n a t e s a n d evaporites; in the lower p a r t fluvial s a n d s t o n e s a n d shales. T h e total t h i c k n e s s o f the f o r m a t i o n is in the o r d e r o f 750 m b u t this decreases to the east a w a y f r o m the fault to zero. T h e f o r m a t i o n c o n t a i n s a variety o f f a u n a that indicate a B a s h k i r i a n age.

Definition: The Ebbadalen Formation is equivalent to the Lower Gypsiferous Series of Gee, Harland & McWhae (1953) but excludes the lateral equivalents of the Minkinfjellet Formation. The formation occurs only in the BiUefjorden Trough, and like the overlying Minkinfjellet and Cadellfjellet units is thickest adjacent to the fault zone on the western margin of the trough, where up to 750m are preserved. It thins rapidly to the east and pinches out about 25kin east of Billefjorden. The type section is at Ebbadalen with reference sections at Cadellfjellet, Odellfjellet and elsewhere. The formation was defined by Cutbill & Challinor (1965) and has been described by Holliday & Cutbill (1972) and Johannessen & Steel (1992).

THE CENTRAL BASIN The upper boundary of the formation is marked by the appearance of the sandstones of the overlying Carronelva Beds, above which cherty carbonates occur and evaporites are rare. The lower boundary is above the red beds of the Hultberget Formation which overlies the coal-bearing sequences of the Billefjorden Group. Lithologies: Facies are extremely variable as Gypsum-anhydrite rocks are an important constituent of the upper part of the formation especially, and are widely developed in the central part of the Billefjorden Trough. They are of the nodular type and formed during early diagenesis in soft sediments (Holliday 1967, 1968). Gypsum was the primary sulphate mineral deposit, while anhydrite formed by solution and reprecipitation. Sandstones form a major constituent of the lower part of the formation. They are light coloured, white, red and green, generally fine-medium grained with horizontal and both large and small-scale cross-stratification. In the central part of the basin they are commonly interbedded with carbonates and shales. Black shales occur with the sandstones in the lower part of the formation; in Ebbadalen, the shales form a thick, clearly defined horizon (the Ebbadalen Shale Beds). Red sandstones, conglomerates and shales occur interbedded in the upper part of the formation adjacent to the fault belt. Conglomerates and sandstones also occur in the east of the basin, e.g. at Cadellfjellet, where they form the Margaretbreen Conglomerate facies. Red beds also occur across the area at the base of the formation. Skeletal calcarenites, commonly oolitic, with sparry calcite cement and little or no lime mud, occur in the east and as thin horizons elsewhere. Locally, a limestone breccia (the Ragnarbreen Breccia of McWhae 1953) is developed at the top of the Ebbadalen Formation. As there is no evidence of tectonism and it occurs in abnormally thin sections lacking sulphates, it is thought to be a solution breccia, resulting from the removal of sulphates. Division: Holliday & Cutbill (1972) examined the complex lateral facies variations within the formation and defined a number of local members, beds and 'facies'. Detailed mapping of key limestone horizons allowed correlation of the different facies. Johannessen & Steel (1992) defined a further member within the formation, and redefined the base to include the red beds of the Hultberget Member, which had previously been assigned to the underlying Svenbreen Formation. The Odellfjellet Mbr: Johannessen & Steel (1992) introduced the member for alluvial fan and related deposits that occur adjacent to the Billefjorden Fault zone. These deposits were originally referred to as the Lower and Upper Red Bed Facies of the Trikolorfjellet Member by Holliday & Cutbill (1972). They consist of red, grey and yellow conglomerates and sandstones, red shales (with gypsum nodules in places) and yellow dolostones. In the lower red beds, conglomerate clasts are mainly quartzose, sorting is poor, stratification irregular and there is rapid lateral variation. The member is up to 400 m thick adjacent to the fault, but to the east it thins considerably and interdigitates with the Trikolorfjellet Member. On the west side of Billefjorden, the 'Pyramiden Conglomerate' (= Pyramiden Beds and equivalent to Elsabreen Beds of Cutbill & Challinor 1965; Dallmann 1993) consists of a group of rudites adjacent to the Billefjorden Fault zone, where they comprise the entire formation and are 300-400m thick. Originally placed in the Minkinfjellet Fm they are now considered to be equivalent to the Odellfjellet Mbr and are placed within it (Dallmann 1993). The Trikolorfjellet Mbr: The type section of the member is in Ebbadalen where it is 186 m thick, although it is thickest (326 m) at Trikolorfjellet from where it is named (Holliday & Cutbill 1972). The member is laterally variable in facies and lithologies; it mainly contains gypsum-anhydrite rocks with interbedded carbonates, but the evaporites are replaced to the west by red shales and then by sandstones and conglomerates of the Odellfjellet Mbr, with which it is equivalent. Thin black limestones and dolostone interbeds are common throughout. A basal sandy fossiliferous limestone is incised as much as 40 m into the underlying strata. Elsewhere, the base is conformable and defined at the bottom of the red beds. In some areas (e.g. at Trikolorfjellet), the Odellfjellet and Trikolorfjellet members interdigitate to the extent that red and white coloured lithologies appear to be cyclic (each cycle typically 15-30m thick), consisting of upward-coarsening red sandstones and conglomerates capped by a white quartzitic sandstone, which is in turn overlain by dolostone (fossiliferous at some levels). Holliday & Cutbill (1972) introduced the term Teltfjellet Mbr for the eastern lateral equivalent of the Trikolorfjellet Mbr. However, this term has fallen into disuse, as the two members may be difficult to distinguish, and therefore the strata are included within the Trikolorfjellet Mbr. The type section of the Teltfjellet Mbr was on Cadellfjellet, where evaporites occur with the same widespread limestone beds as to the west. The carbonates thicken to the east in the upper part of the member in north Biinsow Land and finally form the continuous Urmstonfjellet Limestone Bed. The base of the

71

member is unconformable in the east, where it oversteps onto the Ebbaelva Mbr (Gerritelva Sandstone Mbr of Holliday & Cutbill; see below), the Llulberget and Mumlen fms and the Hecla Hoek basement. The Ebbaelva Mbr: This member comprises grey and yellow sandstones interbedded with grey-green shales. They occur in discontinuous upwardfining cycles in the central and northern parts of the area. Thin black dolomites and white nodular gypsum and anhydrite are interbedded towards the top of the member. In the Ebbadalen area, Holliday & Cutbill identified two sub-units- the upper Ebbabreen Shale Beds and lower Ebbabreen Sandstone Beds, although it is unclear whether they can be traced further than the local area and the names have not been used in later literature. Holliday & Cutbill also introduced the Gerritelva Member. As with the Teltfjellet Member, the name has fallen into disuse, with the strata included in the Ebbaelva Mbr (e.g. Johannessen & Steel 1992) as they are probably the lateral equivalent of the Ebbabreen Sandstone Beds. The Gerritelva Mbr was defined to include 0-70 m of sandstones occurring east of Adolfbukta, containing both horizontal and large-scale cross-bedding and some pebble horizons. The beds are flaggy to massive and commonly gypsum-cemented. Palaeontology and age: Once thought to be unfossiliferous, the Ebbadalen Formation is now known to contain a wide variety of fossils including crinoids, corals, brachiopods and fusulinids. Only the latter two groups have been described to date. These occur mainly in dolostones and shales of the Ebbaelva Member. The brachiopods described by Gobbett (1964) and Holliday (pers. comm.) are on the whole too wide-ranging for an accurate age correlation. However, the occurrence of Striatifera sp. in dolostones high in the Ebbaelva Member and in the basal limestones of the Trikolorfjellet Member may be significant as this genus has previously been regarded as restricted to the Early Carboniferous epoch (Muir-Wood & Cooper, 1960). Fusulinids from the upper part of the formation belong to the P. antiqua zone of Cutbill and correlate with the Bashkirian stage of Russia. No Moscovian species occur below the Minkinfjellet Member, and the top of the Ebbadalen Formation probably corresponds to the Bashkirian/Moscovian boundary. The formation is therefore of Bashkirian age.

4.7.5

Hultberget Formation (CampbeHryggen Subgroup)

This u n i t was originally the (upper) H u l t b e r g e t M e m b e r o f the S v e n b r e e n F o r m a t i o n o f the Billefjorden G r o u p (Cutbill & C h a l l i n o r 1965), the lower S v e n b r e e n U n i t being the S p o r e h o g d a M e m b e r . H o w e v e r the N o r s k P o l a r i n s t i t u t t m a p p e d a b r e a k b e t w e e n the t w o m e m b e r s a n d t h e H u l t b e r g e t u n i t h a d m o r e affinity with the overlying strata because o f its red beds. T h e S v e n b r e e n F o r m a t i o n was t h u s d i s c o n t i n u e d as a useful m a p p i n g u n i t a n d divided b e t w e e n C a m p b e l l r y g g e n S u b g r o u p a n d the Billefjorden G r o u p . T h e H u l t b e r g e t M e m b e r o f Cutbill & C h a l l i n o r was described as 7 9 m thick w i t h a coal s e a m at the base a n d overlain by grey to red shales a n d s a n d s t o n e s . T h e coal s e a m has m o r e affinity w i t h the newly defined M u m i e n F o r m a t i o n below. T h e f o r m a t i o n consists o f red a n d p u r p l e shales, m u d s t o n e s , siltstones, s a n d s t o n e s a n d thin i r o n s t o n e b a n d s w h i c h m a y be recystallized l i m o n i t i c m u d s . L i m e s t o n e n o d u l e s m a y also o c c u r in s o m e o f the shale beds. M o s t beds are parallel l a m i n a t e d or crossb e d d e d ; s a n d s t o n e s are fine to m e d i u m grained. N o r t h w e s t o f Elsabreen, c o n g l o m e r a t e layers are present. T h e strata p r o b a b l y r e p r e s e n t s t r e a m a n d o v e r b a n k d e p o s i t s w i t h i n a n d a d j a c e n t to alluvial fans at the base o f the fault.

4.8

BiHefjorden Group (Early Carboniferous)

I n the c u r r e n t s c h e m e the Billefjorden G r o u p in the type area is n o w defined by the t w o c o n s t i t u e n t f o r m a t i o n s : M u m i e n a n d H o r b y e b r e e n (SKS, D a l l m a n n et al. 1996). This r e a r r a n g e m e n t resulted f r o m the division o f the S v e n b r e e n F o r m a t i o n o f Cutbill & C h a l l i n o r (1965) into its u p p e r H u l t b e r g e t M e m b e r , d i s t i n g u i s h e d by red beds, to b e c o m e the lowest f o r m a t i o n o f the G i p s d a l e n G r o u p a n d the lower S p o r e h o g d a M e m b e r to be redefined as the newly n a m e d M u m i e n F o r m a t i o n .

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CHAPTER 4 unconformably on the Hecla Hoek metamorphic basement with a thin basal conglomerate of locally-derived pebbles. Lithologies: Two lithofacies can be distinguished in the formation constituting the two members. The upper member consists of dark grey or black carbonaceous shales, associated with thin coals and some sandstones. The lower member in Dickson Land is characterized by massive, lightcoloured, thick-bedded, coarse sandstones (Johannessen & Steel 1992).

Since the C a m b r i d g e w o r k , m o s t s e d i m e n t o l o g y a n d stratigrap h y has been carried o u t either by g r o u p s f r o m the University o f Bergen (Gjelberg & Steel 1981; Gjelberg 1987; J o h a n n e s s e n & Steel 1992) or the N o r s k P o l a r i n s t i t u t t , w h o have recently r e - m a p p e d the area ( L a u r i t z e n et al. 1989, C 8 G ; D a l l m a n n 1993; D a l l m a n n et al. 1994, C7G). B o r e h o l e a n d seismic d a t a have also been collected by oil c o m p a n i e s interested in the area, s o m e o f w h i c h have been p u b l i s h e d ( Y e v d o k i m o v a , V o r o k h o v s k a y a & B i r y u k o v 1986).

4.8.1

The Birger JohnsonqeUet Mbr: This is the coal-bearing part of the formation, made up of small cycles of shale and siltstone which are locally carbonaceous and pass into coaly shale and coal. Plant remains are common. Up to 18 coal seams are present, from 0.1-1.45 m in thickness. Underlying root horizons or soil profiles are absent, although root horizons do occur elsewhere in the member (Abdullah et al. 1988). There is considerable lateral facies variation and also thickness variation (7-57 m) within the member. The base is defined as the first thick sequence of coal seams. The Sporeh~gda Mbr: This member consists mainly of massive white, thickbedded, coarse sandstones 20-76m thick. The whole unit shows crossbedding, wash-outs and rapid lateral changes in thickness of individual beds. Allochthonous plant debris and coaly clasts are common. Sandstones in the lower part contain large carbonaceous fragments and moulds of Lepidodendron stems. Towards the east, shales occur between the sandstone units. In the Ebbadalen area, the facies is fine-grained and contains several thin coals, which are usually associated with carbonaceous black shales containing plant remains, into which they pass laterally and vertically. Only rarely, e.g. at Hultberget, north of Ebbadalen, do the coals lie on a rootlet horizon. Although the individual seams have little lateral continuity, the coals fall into three recognisable horizons, two of which can be traced over quite a wide area. In places the shales contain ironstone concretions, but they are not as abundant as in the overlying Birger Johnsonfjellet Mbr. There is a thin basal conglomerate of locally-derived pebbles where the sandstones rest directly on basement rocks, which is absent elsewhere. Otherwise, medium and coarse conglomerates are rare. Yevdokimova et al. (1986) correlated the upper part of this coal-bearing facies in their section, only a small distance to the south, with that of the Birger Johnsonfjellet Mbr west of Billefjorden.

Mumien Formation

This f o r m a t i o n is the lower p a r t o f the original S v e n b r e e n F o r m a t i o n , its u p p e r b o u n d a r y being below the lowest red beds o f the H u l t b e r g e t F o r m a t i o n . It is a t e r r i g e n o u s u n i t p r e s e n t in the Billefjorden area, with a thickness o f u p to 230 m. It c o n t a i n s two m e m b e r s - Birger J o h n s o n f j e l l e t a n d S p o r e h o g d a . T h e S p o r e h o g d a M e m b e r c o n t a i n s massive coarse s a n d s t o n e s w i t h m i n o r shales a n d a l l o c h t h o n o u s coal, w h e r e a s the Birger J o h n s o n f j e l l e t M e m b e r c o n t a i n s n u m e r o u s coal seams w i t h i n a p r e d o m i n a n t l y shale a n d siltstone sequence (Fig. 4.13). T h e f o r m a t i o n is i n t e r p r e t a t e d as a terrestrial unit, with dep o s i t i o n w i t h i n a large fluvial system for the S p o r e h o g d a M e m b e r b u t c h a n g i n g to lacustrine a n d v e g e t a t e d f l o o d p l a i n e n v i r o n m e n t s for the Birger J o h n s o n f j e l l e t M e m b e r . D e p o s i t i o n o c c u r r e d d u r i n g Visean a n d possibly into S e r p u k h o v i a n time.

Definition: The Svenbreen Fm was defined by Cutbill & Challinor (1965) as 'the upper coarse sandstone series' of the Billefjorden Gp which crops out only in the East Spitsbergen Basin. The Mumien Fm was introduced (SKS, Dallmann et al. 1996) for the lower member of the Svenbreen Fm. The type section is on Birger Johnsonfjellet. Thicknesses are greatest to the east of the Billefjorden Fault Zone, with a maximum of 230m at the northern end of Billefjorden. The formation thins rapidly to the west and east and is absent west of the East Dickson Land Axis and in central and eastern Olav V Land. The upper boundary is here redefined as the base of the alluvial red bed sequence of the Hultberget Fm (Campbellryggen Subgroup), which locally rests on the coal-bearing strata below (Cutbill & Challinor 1965). In most of Dickson Land the Cambpellryggen Subgp is absent and the Mumien clastic rocks are overlain by limestones of the Dickson Land Subgp. The basal sandstones of the Mumien Fm in the west are concordant on the upper shales of the Horbyebreen Fm below, though there may be a disconformity, as in the east the lower formation is absent and the Mumien Formation rests

Rock units 13_

Thin-bedded sandstones and shales, commonly red

Red-beds, sandstones and conglomerates

Gjelberg & S t e e l (1981)

O n(3 Z I.U -J < a (f) 13_

Gjelberg (1987)

Abdullah et al. (1988); Michelsen & Khorasani (1991)

Johannessen & Steel (1992)

Dallmann (1993); McCann & Dallmann SKS and this work (1995)

EBBADALEN FORMATION

Hultberget Mbr

Hultberget Mbr

SVENBREEN FM

HULTBERGET FM

13_ O n~ (_9 Z LU J < a co

13. m (~

Hultberget Mbr

Coal-bearing siltstone / shale sequence

s :~ O r~ (.9

Massive thick-bedded sandstones

Z Ill r'~ I:::E O ii UJ "J ._]

Siltstones, shales and coal

Cutbill & Challinor (1965)

Palaeontology and age The formation contains a plentiful Early Carboniferous macro-flora (Forbes et al. 1958) and micro-flora (Playford 1962/1963), described in Chapter 17. In general it is difficult to separate the Mumien and Horbyebreen formations on palaeontological grounds, as no stratigraphically separate assemblages are apparent in the macro-flora. However, Playford (1962/1963) recognized his Aurita microspore assemblage in the Mumien Formation and upper Horbyebreen Fm, concluding that these strata have a Visean age, possibly extending to earliest Serpukhovian. There is some statistical evidence that this assemblage can

SVENBREEN FORMATION

Birger Johnsonfjellet Mbr

Birger Johnsonfjellet Mbr Sporehegda Mbr (Herbyebreen Fm)

Sporeh~gda Mbr

Fig. 4.13. Stratigraphic schemes for the Billefjorden Group.

MUMIEN FM

Z

Sporehegda Mbr

HORBYEBREEN FORMATION Hoelbreen Mbr Triungen Mbr

13_ O r~ (3 UJ a n," O ii Ill ._A .,,A m

THE CENTRAL BASIN be subdivided at the junction betweenthe Mumien and Herbyebreen fms (Cutbill & Challinor, 1965) and that this may approximate the ViseanSerpukhovian boundary. Retiolites radforthii Staplin, is found only in the Mumien Fm. In this case, the Mumien Fm would be entirely Serpukhovian.

4.8.2

Harbyebreen Formation

The H e r b y e b r e e n F o r m a t i o n lies u n c o n f o r m a b l y on Proterozoic basement rocks in D i c k s o n L a n d and s o u t h e r n N y Friesland. It is variable in thickness f r o m 57 to 2 0 0 m thinning to the west. It contains sandstone, conglomerate, shale a n d coal, c o m m o n l y occurring in cyclic sequences. The lower part of the f o r m a t i o n is d o m i n a t e d by the coarser-grained lithologies a n d assigned m e m b e r status (Triungen Member); the u p p e r part contains most o f the shales and coals and forms the H o e l b r e e n M e m b e r . Deposition is t h o u g h t to have been in a continental setting within a small and restricted basin. It was p r o b a b l y f a u l t - b o u n d e d to the east, a n d the sediment source was also probably in that direction. Facies show large lateral variations. The T r i u n g e n M e m b e r was mainly deposited by westward-flowing braided streams with o v e r b a n k deposits; the H o e l b r e e n M e m b e r by n o r t h w a r d - f l o w i n g m e a n d e r i n g streams in a s w a m p y floodplain environment. The f o r m a t i o n is o f T o u r n a i s i a n and possibly of Late F a m e n n i a n a n d / o r Visean ages on the basis o f microflora.

Definition: The unit was defined by Cutbill & Challinor (1965) as the lower formation of the Billefjorden Gp. It is restricted in outcrop to central Dickson Land and southern Ny Friesland. The upper boundary may be a disconformity in view of the basal Mumien Fm overstep to the east, but sandstones of the Mumien Fm concordantly overlie the shales at the top of the Herbyebreen Fm. The base is unconformable on preCarboniferous rocks. Lithologies and division: The formation consists of a cyclic sequence of shales, coals, sandstones and conglomerates from 57-200m thick. Fine sediments and coals predominate in the upper part, while the lower part consists entirely of sandstones and conglomerates. This has led to a division into two members: the Hoelbreen and Triungen Mbrs. Hoelbreen Mbr: The type section for the Hoelbreen Member is on Birger Johnsonfjellet where it is 146m thick. The member thins markedly to the west, e.g. at Gonvillebreen it is only 54 m thick. Within this upper member, thinly bedded, cyclic and laterally persistent coal-bearing carbonaceous shales and siltstones predominate. The siltstones show occasional low-angle cross-bedding, though it is usually flat or wavy. Dark grey, shaly, micaceous argillites, 0.5m thick usually occur above the coal seams. Fine-grained sandstone interbeds up to 2 m thick and showing some cross-bedding occur, especially in the east, in the lower part of the sequence, but they are locally developed and laterally impersistent. 10-15 cycles of sand-silt-clay-coal have been recognised. 10% of the member is sandstone; 50% is dark grey siltstone containing plant remains; 20% is made up of argillites and 20% of coal. The coals are generally quite thin and die out laterally, but they are more extensively developed in two well-defined horizons in the south-east of the outcrop, seams varying in thickness from 0.66-7.4 m. In the region of Pyramiden, the coals are sufficiently thick (up to 9m) to be mined. Transported plant remains are common in all lithologies, but are generally poorly preserved. In-situ plant fossils are rare and there is generally a lack of seat-earths, indicating that the coals are mainly allochthonous. However, seat-earths and rootlet beds are present locally. Triungen Mbr: The type section of this lower member is beside Gonvillebreen where it is 99 m on Odellfjellet. There is a general reduction in coal and carbonaceous material towards the west. Thicknesses are irregular, from 5-100m due to lateral facies variations. The dominant lithologies are thick-bedded sandstones and almost uncemented heterogeneous conglomerates. The latter show coarse cross-bedding and contain a variety of pebbles, including white, pink and purple quartzites, black and grey chert and rare mica-schist. The upper 20m are less conglomeratic, and there is a transition into the carbonaceous sandstones and shales of the Hoelbreen Mbr. The upper boundary is at the top of the highest thickbedded sandstone. The conglomerates around the Billefjorden Fault Zone, e.g. at Birger Johnsonfjellet, are noticeably coarser than further west, e.g. at Gonvillebreen.

73

Palaeontology and age: There is an abundant macroflora in the Mumien and Horbyebreen Formations, though no stratigraphically separate assemblages have been recognized. However, the microflora has proved more useful. Playford (1962/63) recognized his two distinct assemblages in these strata, defining the Aurita and Rarituberculatus zones, which indicate a Visean and Tournaisian age. The lower Rarituberculatus (Tournaisian) assemblage is restricted to the Horbyebreen Fm. However, the lower member does not yield a microflora, except in its uppermost part. The upper Hoelbreen Mbr contains the Rarituberculatus assemblage for more than half its thickness. There is then a break, and the overlying strata contain the Aurita assemblage. This break is not marked by any lithological change. The Aurita assemblage is also present in the overlying Mumien Formation but there is some evidence that the Aurita assemblage can be subdivided at the disconformity between the Mumien and Horbyebreen fms which may mark the Visean/Serpukhovian boundary (Cutbill & Challinor 1965).The assemblage, according to Playford, could possibly extend to Early Serpukhovian time. The Horbyebreen Fm is thus of Tournaisian and Visean age. However, given the rarity of preserved palynomorphs from most of the Triungen Member, it is possible that the lowest part may have a Famennian age, and this appears to have been confirmed (van Veen, pers. comm.).

4.9

The structure and development of the Central Basin

The Basin is d o m i n a t e d by three kinds of Paleogene structure. (i) The eastern front o f the thrust a n d fold belt of the West Spitsbergen O r o g e n m a r k s a distinct b o u n d a r y w h e t h e r a steep m o n o c l i n e or an eastward verging thrust front. (ii) In line of the fault, the Billefjorden a n d L o m f j o r d e n fault zones, thrust structures have c o n c e n t r a t e d also with easterly vergence resulting in some thickening. These structures a p p e a r to have been generated t h r o u g h the Paleogene strata or to the n o r t h t h r o u g h decollement zones in Mesozoic and Paleozoic strata. The G i p s h u k e n F o r m a t i o n contains examples o f such bedding-shear as m o n i t o r e d in the ellipsoidal a n h y d r i t e - g y p s u m concretions. Similar facies in the lower gypsiferous strata in the Billefjorden t r o u g h were protected by the N o r d f j o r d e n H i g h ( H a r l a n d , M a n n & T o w n s e n d 1988). The result was d e f o r m a t i o n c o n c e n t r a t e d in the older fault zones (Fig. 4.14; Andresen, H a r e m o & Bergh 1988). (iii) T h e m o s t obvious feature of the Central Basin is the oval shaped o u t c r o p o f the Paleogene strata in which the d e p o c e n t r e shifted s o u t h w e s t w a r d s so that at places, w h e r e the strata are

WEST

EAST

I Tp --'~ f-I (a)FLOWERDALEN-MARMIERFJELLET

Sea level 1000 metres

i

5OO

1'.0

2.0

kilometres of Festningen sandstone

__f••.base ~

f- I

~

-

-

-

-

~

T#r_- - _ ..-,,/.,-I KT ....

~

~

~_._..---..~ KT

s

~'Sea level

(b) A D V E N T D A L E N - ESKERDALEN (north side)

base of C r e t a c e o u s shale

~ f-I (c) REINDALEN (south side)

~ ~t'"-base of Festningen sandstone

Abbreviations: T - Tertiary Ju - Upper part of the Janusfjellet Subgroup JI - Lower part of the Janusfjellet Subgroup

Sea level

KT - Kapp Toscana Formation S - Sassendalen group TP - Tempelfjorden group f-I - fault line

Fig. 4.14. Simplified structural cross-sections of the Central Basin (from Parker, 1966) to show deformation and tectonic thickening above the southern extension of the Billefjorden Fault Zone, f-1 in sections (a), (b) and (e), and the anticline thrust structure diverging to the east, south of the fault in Nordenski61d Land.

74

CHAPTER 4

thickest, they are truncated by faulting (probably transpressive) along the west Spitsbergen orogenic front (e.g. Steel et al. 1981). The structure has been further delineated by seismic studies of the Polish group (Guterch et al. 1978; Guterch, Pajchal & Perchuc 1982; Guterch & Perchuc 1990). It is not so obvious to what extent a Mesozoic basin structure coincided with the Central Basin. Because the basal Paleogene Firkanten Formation unconformably oversteps northwards successive members of Early Cretaceous Carolinefjellet Formation in a seemingly plane erosion surface which itself was followed by southward tilting of Spitsbergen. Late Triassic strata thicken eastwards and Early Triassic strata possibly westwards away from a delta source, so that there is an incipient differential Sassendalen Group subsidence in the west along the orogen. Late Paleozoic structures are best seen emerging northwards, and Early Carboniferous strata reflect the Devonian fault pattern. West of the Billefjorden Fault Zone (BFZ) was the Nordfjorden High bounded on the West by the West Spitsbergen Fault Zone beyond which the St Jonsfjorden Trough is considered in Chapter 9. The Billefjorden Trough east of the BFZ and a similar less pronounced trough further east related to the Lomfjorden Fault Zone accumulated sediments in isolated basins before Wordiekammen Limestone times. It is suggested here that three successive groups of factors operated.

(1) During Carboniferous time especially, but right through Jurassic time at least, the three mentioned fault zones were intermittently reactivated but not in a strike-slip sense. (Chapters 17 and 18). (2) Upward tilting to the north was demonstrably active in late Cretaceous time with the elimination of Mesozoic strata beneath the Paleogene strata at around the latitude of Kongsfjorden so giving the characteristic outcrop pattern with the older rocks in the north. Just prior to this differential uplift was a marked Albian differential subsidence to develop a rapidly increasing thickening of the Carolinefjellet Formation. These two evidences may point to a single tilting operation in which differential mantle heating in the north replaced the long period of slow cooling platform subsidence. (3) The marked localisation of the Central Basin into the Central Tertiary Basin could well have a Paleogene strike-slip component as a partial pull-apart (transtensile) basin in its initial stages. When, by Late Palaeocene and Eocene time transpression, dominated the West Spitsbergen Orogeny compressive stresses were effective throughout the basin area as seen in structures localised especially near the old fault zones. Such compression could have contributed to a final downward buckling to depress the basin further in which sedimentation from the uprising welt filled the space available (Chapter 20).

Chapter 5 Eastern Svalbard Platform W . B. H A R L A N D 5.1 5.2 5.3 5.4 5.4.1 5.4.2 5.4.3 5.4.4 5.4.5 5.5 5.5.1 5.5.2 5.6

with a contribution by SIMON

Platform strata, 75 Igneous rocks, 76 Submarine outcrops, 76 Northeastern Spitsbergen, Wilhelmuya and Hinlopenstretet, 77 Northeastern Spitsbergen: Permo-Carboniferous terrane, 77 Northeastern Spitsbergen: Triassic terrane, 77 Wilhelmoya and Hellwaldfjellet, 77 Islands of Hinlopenstretet, 79 The structure, 79 Southwestern Nordaustlandet, 80 Earlier work, 80 Stratal succession, 81 Kong Karls Land (W.B.H. & S.R.A.K.), 83

The Platform sequence (of younger rocks) i.e. latest Devonian, Carboniferous/Tournasian through Albian (and excluding Tertiary strata on land at least) appears once to have extended east of Spitsbergen in one sheet of which little now remains above sea level. It comprises two supergroups: Bfinsow Land and Nordenski61d Land. The map (Fig. 5.1) illustrates that each of the islands rests on a much larger shelf, no deeper than 100 m and that with the exception

o~

5.6.1 5.6.2 5.7 5.7.1 5.7.2 5.7.3 5.7.4 5.7.5 5.8 5.8.1 5.8.2 5.8.3 5.9

Fig. 5.1. Map of the eastern platform area of Svalbard showing the main place names and principal bathymetric features (adapted from 1:2 000 000 bathymetry chart of the Western Barents Sea, Norsk Polarinstitutt, Oslo 1989; compiled by Kristoffersen, Sand, Beskow & Ohta).

Earlier work, 83 Stratal succession, 83 Barentsoya, Edgeoya and Tusenoyane, 86 Earlier work, 86 Stratal succession, 87 Sub-surface stratigraphy, 89 Biostratigraphy/age estimates, 89 Structure and igneous bodies, 91 Hopeu, 91 Earlier work, 92 Succession from outcrop, 93 Subsurface succession, 93 Correlation of four exploratory wells: Edgeoya and Hopeu, 93

of the outlying islands of Kong Karls Land and Hopen the 100m isobath contains them within the Spitsbergen shallows. In these circumstances, it would appear to be somewhat fortuitous as to what strata are preserved above sea level and it is perhaps remarkable that, if relatively thin strata with a maximum combined and exposed thickness in the area from (Tournaisian) through ?Barremian of c. 2 km, some representatives occur on each island with neither younger nor older rocks. If we plot the TriassicJurassic boundary, say the Rhaetian stage, it occurs at the top of the east Spitsbergen, south Nordaustlandet and south Edgeoya outcrops at heights respectively of about 550, 350 and 500 m a.s.l., at about 0-100 m at Kong Karls Land and at 370-300 m in Hopen. Thus departures from sea level over distances of 350 km N to S and 200 km E to W hardly exceed 500m with average gradients of perhaps 300m in 300 k m - about half a degree. It is therefore reasonable on present evidence exposed above sea level to refer to this as a platform. On the other hand local dips may be very much steeper. One might speculate that the highly resistant Kapp Starostin Formation may be in part responsible for the wide extent of the shallow water around the islands. One striking feature which distinguishes eastern from western Svalbard is the greater degree of Late Jurassic Early Cretaceous basic igneous activity, mainly evident in sills. They are often thick enough to form major topographical features and with evidence of volcanism in the east. Indeed in Kong Karls Land not only do lavas occur but the stratigraphic successions there appear to show more Mesozoic disturbance than elsewhere in Svalbard for this interval.

5.1

H~ y

R. A. K E L L Y

P l a t f o r m strata

In each area discussed the rock units named and employed are explained. The sedimentary (and volcanic) successions as recorded in the separate areas considered here are described in this chapter as follows. Northeast Spitsbergen and Wilhelmoya (Section 5.4) is, for convenience, taken as the area east of the Lomfjorden Fault in which mainly Permian and Triassic strata crop out. Latest Triassic and Jurassic strata are recorded in the tops of the mountains of Hellwaldfjellet and Wilhelmoya. The islands in Hinlopenstretet are mainly basic igneous rocks, presumably late Mesozoic sills and dykes. Southwestern Nordaustlandet (Section 5.5) is in effect an extension of the above mainland area with Permian-Triassic successions but no record of latest Triassic or Jurassic strata. The Paleozoic strata are seen to rest unconformably on Precambrian (Caledonian) basement.

76

CHAPTER 5

Kong Karls Land (Section 5.6) is a small isolated archipelago ranging Late Triassic through Early Cretaceous strata (with lava flows). Jurassic faunas are especially rich. Barentsoya, Edgeoya and Tusenoyane (Section 5.7) is a large, almost exclusively Triassic terrane with three minor Permian inliers but no Rhaetian or younger strata recorded. The two islands are penetrated by late Mesozoic basic sills and such rocks form the thousand islands to the south (Tusenoyane). Two deep wells, Plurdalen-1 and Raddedalen-1 penetrate strata at least well into Early Carboniferous and possibly earlier units. Hopen (Section 5.8) is a singularly linear island again probably exclusively of Late Triassic strata. Two wells (Hopen-1 and Hopen-2) penetrate Early Triassic and Permian to Carboniferous strata. The four wells are compared in Section 5.9.

5.3

Data from the area roughly east of Nordaustlandet, Edgeoya and Hopen and west of longitude 35~ were recorded by Elverhoi & Lauritzen (1984) and yielded a map with predominant Quaternary rock fragments classified mainly as Hecla Hoek in the north around Kvitoya, as chert and silicified limestone (typical of the Tempelfjorden Group) south and east of southern Nordaustlandet and east of Edgeoya, with the remaining larger area yielding mostly sandstones probably Mesozoic. Elverhoi et al. (1989) divided the northwest Barents Sea into six structurally defined elements: 1. 2. 3.

5.2

Igneous rocks

The mainland of Spitsbergen, Nordaustlandet, Kong Karls Land, Barentsoya and Edgeoya are all characterized by basic intrusions. In addition Kong Karls Land exhibits volcanic lavas. The igneous activity spanned ?Kimmeridgian to Barremian time. Evidence also suggests that the rocks belong to one main igneous suite. Some of the characteristics will be mentioned here and not necessarily repeated under subsequent headings. One obvious feature is that the rocks are generally more resistant than their host strata which they protect. They thus crop out in a disproportionally large area for their bulk and often have a significant control of topography. Nearer to sea level the sedimentary rocks have often been removed and many small islands expose only basic rocks. This is typical of the islands in Hinlopenstretet, in Tusenoyane and around Kong Karls Land. It may well be that this is only part of a larger province well exemplified in the less accessible archipelago of Franz Josef Land. The petrology of these basalts, dolerites and occasional gabbros has been studied by relatively few workers because of their relative uniformity and the thorough nature of the early investigations. Historically the rocks were noticed by Nordenski61d with their peculiar 'hyperite' facies. This is softer rock and is not often encountered. Backlund was the first to make a systematic study of these rocks (1907a, b, 1908, 1911, 1920) from the Arc of Meridian Surveys of 1899-1901. The 1907 publication is a monograph on the 'diabases' of eastern Svalbard beginning with a thorough review of previous work, then outlining knowledge of the rocks in Spitsbergen. The principal work is on the Storfjorden rocks and especially those of Edgeoya and Barentsoya with a detailed description of their many occurrences. The main body of the work is petrographic with optical studies of the principal minerals, plagioclase, pyroxene, titano-magnetic, olivine and with notes on apatite and quartz and then with chemical analysis of the rocks including marginal facies. This laboratory work in St Petersburg can hardly be surpassed. The second fascicle (1908) described similar rocks observed in the course of a traverse from Johnstonbukta in Storfjorden to Billefjorden (via the high mountains including Backlundtoppen). Backlund (1907b) had already made a study of the Kong Karls Land and Franz Josef Land material collected on earlier expeditions. A more accessible and convenient study of the dolerite and basalts of Svalbard, and with further chemical analysis (Tyrrell & Sandford 1933) confirms the view of a variety of facies but still with a remarkably uniform character and chemical composition. Analyses compare closely with those from British quartz dolerites and tholeiitic rocks of the British Tertiary Province, with Karoo basalt lavas, Deccan traps and South American Gondwana dolerites. An average composition of four Spitsbergen dolerites was shown as follows: SiO2, 49.2; A1203, 14.4; Fe203, 3.4; FeO, 10.1; MgO, 5.4; CaO, 9.4; Na20, 2.0; K20, 1.0; H20, 1.6; TiO2, 2.9; P20, 0.2; MnO, 0.4; = 100%.

Submarine outcrops

4. 5.

north of Kong Karls Land, gently southward (1-3 ~ dipping strata with main fold south of Kvitoya; Kong Karls Land Structural High with intrusives; south and southeast of Kong Karls Land, structurally disturbed; around Storbanken sediments are flat lying; south of the Olga Basin is a major synform.

The distribution of Jurassic and Cretaceous deposits offshore on the northwest Barents Shelf was initially analysed from grab samples (Dibner 1968; Bjorlykke, Bue & Elverhoi 1978). Much of the shallow bedrock geology has been deduced from the analysis of Mesozoic clasts which occur in Late Quaternary sediments and which are believed to have been locally derived. Subsequently much seismic data has become available as well as information from shallow cores (e.g. Elverhoi & Lauritzen 1984; Gramberg & Pogrebitskiy 1984). The data were reviewed by Elverhoi et al. (1989) and Dowdeswell (1988). Nagy (1973) identified Oxfordian to Hauterivian macrofaunas including buchiid bivalves, belemnites and onychitids in dredged blocks from Svalbardbanken. Edwards (1975) recognized Helvetiafjellet-Carolinefjellet lithologies from blocks from central Svalbardbanken and Janusfjellet Subgroup lithologies on the northeast central part and more widely on the flanks. Bjaerke & Thusu (1976) listed Cretaceous and possible Jurassic palynomorphs from blocks on the south side of Spitsbergenbanken, suggesting the presence of Rurikfjellet and Carolinefjellet formations or their equivalents. Elverhoi et al. (1989) recognized widespread Rurikfjellet Formation especially in fine grained lithologies, although Jurassic and Cretaceous sandstones were more difficult to separate from those of the Wilhelmoya Formation. Early Cretaceous trace- and body fossilrich sandy limestones occurred more distally from the clastic sources, but indicated shallow marine conditions and showed affinities with the Tordenskjoldberget Member of Kong Karls Land. Sideritic cements in the limestones suggested a meteoric water origin of undetermined date. Feldspathic sandstones are comparable to those of the Kong Karls Land Formation and with the Helvetiafjellet Formation of Kvalvgtgen on the east coast of Spitsbergen and are related to the Kong Karls Land volcanics. Dolerites are particularly common northeast of Hopen. ,~rhus et al. (1990) described cored sections from the Bjornoya Basin/east Bjarneland Platform. Here a condensed marine sequence of latest Jurassic to Early Cretaceous (Volgian-Barremian) age was penetrated. Dating of the sequence was by buchiid bivalves which gave latest Volgian to Hauterivian ages (Buchia cf. unschensis, B. cf. volgensis, B. okensis, B. keyserlingi and B. cf. sublaevis) and 47 dinoflagellate taxa which gave Volgian to Barremian ages. Other bivalves, brachiopods, cirripedes and foraminifers were also recognised. Although Late Cretaceous sediments are not recognized in the northwest Barents Shelf, they are present under Cenozoic cover in the Nordkapp Basin, the Tromso Basin/Senja Ridge area, Bjornoy Basin and Hammerfest Basin in the southwest Barents Sea (Faleide, Gudlaugsson & Jacquart 1984). Late Cretaceous sediments are also known from Franz Joseph Land where a Cenomanian transgressive sandstone occurs, and in the northeast Barents Sea (Dibner 1970, 1978). Erratics containing inoceramid bivalves have been brought onshore in southern Novaya Zemlya (Cherkesov & Burdykina 1981).

EASTERN SVALBARD PLATFORM

5.4

Northeastern Spitsbergen, Wilhelmoya and Hinlopenstretet

The Lomfjorden Fault Zone is a convenient western boundary to this area which is considered in three parts (1) the Permian-Carboniferous outcrops east of that fault zone from Lomfjordenhalvoya, through Olav V Land to Akademikerbreen. (2) The Triassic strata of eastern Olav V Land and Wilhelmoya (3) the islands of Hinlopenstretet (and southeast of Wilhelmoya). Much of the mainland is ice-covered and the islands are separated by water. The result is that the three contrasting rock types: Mesozoic dolerites; Mesozoic strata (mostly Triassic); Permo-Carboniferous strata while easy to identify, even from a distance, are hardly anywhere exposed in contact. Moreover, the area is relatively remote and while the rocks were long known in the broad outline indicated above it was only since about 1953 that more detailed studies became available. From the above distribution of three rock types the early maps of this area were constructed e.g. by Nathorst (1910), Frebold (1935), Orvin (1940). The western limit treated in this section approximates the eastern limit of the early Cambridge exploration of Ny Friesland (e.g. Harland & Wilson 1956 and Harland 1959). Indeed the complex fault pattern in Lomfjordenhalvoya with inliers of Hecla Hoek surrounded by Permian and Carboniferous outcrops is separated in this treatment according to age. Hence there are two distinct terranes, Permo-Carboniferous and Triassic separated by wide expanses of ice except west of Hinlopenbreen and at the southwestern head of Negribreen.

5.4.1

Northeastern Spitsbergen: Permo-Carboniferous terrane

The earliest detailed succession is due to Cutbill (1968). His maps of this terrane, largely followed on a smaller scale by Lauritzen & Worsley (1975), are redrawn in Fig. 5.2, based on earlier C.S.E fieldwork and the later work in conjunction with Amoseas. Cutbill's stratigraphic scheme, modified only according to rank of units to be consistent in this volume with SKS recommendations, is as follows. It is based on his measured sections at Polarisbreen, Komarovfjellet and Malte Brunfjellet. Lauritzen & Worsley from work in the Lomfjorden area added further sections at Mjolnerfjellet and Eremitten and revised some of Cutbill's conclusions. The following account is intended to combine and summarise those data from different sections and interests: Cutbill giving biostratigraphic data and Lauritzen & Worsley lithological.

Tempelfjorden Group. As in most of Spitsbergen, the sole representative of the Tempelfjorden Group is the Kapp Starostin Formation. Kapp Starostin Formation, 140+ m (mid to Late Permian). Complete exposure was nowhere recorded; but at Eremitten more intermittent resistant beds comprise about 50% of the succession where a highly siliceous biomicrite bed is overlain by silty shales of presumed Triassic age. Typical lithologies reported are sandy biosparites in which the bioclastic fraction is dominated by brachiopod debris. Glauconite was seen in most specimens suggesting correlation with the Hovtinden Member.

Gipsdalen Group Gipshuken Formation. 140-179 m (Artinskian). Similarly perhaps less than half of the succession is exposed with the harder beds only being described, the most distinctive rock being a brecciated, cavernous dolostone suggestive of evaporites and dolomitic micrites. Wordiekammen Formation. This carbonate unit extends from the Central Basin with similar facies but is somewhat thinner. Tyrrellfjellet Member. 100 to c. 130m. (Asselian & Sakmarian). The upper part is poorly exposed and may be calcareous flaggy sandstone and the main and lower part is of elastic dolostones. Rugofusulina arctica, and Schwagerina anderssoni were recorded at the base. Cadellfjellet Member. c. 40 m (Gzhelian) More of this unit is exposed and largely sandy limestone and biomicrite, the latter containing Quasifusulina longissina and Montiparus montiparus. Malte Brunfjellet Formation. 60-70m (Late Moscovian). Complete sections are exposed and comprise biomicrites in the main upper part with fusiline faunas and calcareous sandstones in the lower part Beedeina

77

rockymontana, Wedekindellina dutkevichi, Pseudostaffella sphaeroidea are characteristic. Cutbill suggested that this, his Minkinfjellet Formation, represents a marine transgression because there appears to be no equivalent to the Ebbadalen Formation here. It does, however, occupy a basin related to the Lomfjorden Fault Zone and is so distinguished from the Minkinfjellet Formation of the Central Basin.

Billefjorden Group Mumien Formation. A basin equivalent of the Mumien Formation is present, but no representative of the lower (Horbyebreen) formation of the Billefjorden Group is recorded so that the succession is not only thinner but less complete than in the Billefjorden trough. Cutbill recorded only about 40 or 50 m of sandstone beneath his Minkinfjellet Formation resting on Hecla Hoek strata and none at Malte Brunfjellet. Lauritzen & Worsley argued for a greater thickness, partly on the basis of observations in the Lomfjorden area and partly by reinterpreting as Mumien Formation the lower part of Cutbill's Minkinfjellet Formation. The argument seems reasonable so that about 100 m is suggested. The formation contains spores of the Aurita zone assemblage (Playford 1962/63) suggesting a Visean (and possibly Serpukhovian) age.

5.4.2

Northeastern Spitsbergen: Triassic terrane

This terrane was originally almost u n k n o w n territory, and previously referred to as Terre Glac6e Russe (see Fig. 1.7), has been included in the relatively newly named Olav V Land. It is largely dominated by an ice sheet with glaciers draining into the sea through Triassic hills at its margins. Its western boundary is the range of high mountains of Hecla Hoek rocks and the strip of Permo-Carboniferous rocks. It so happens that the two highest mountains to the east are at Hellwaldfjellet and Wilhelmoya. These preserve Rhaetian and Jurassic strata in their tops and so have received more attention. Accordingly these two areas are reported in the Section 5.4.3. The southern boundary is at Negribreen, the largest glacier reaching the sea in Spitsbergen. Backlund (1908) traversed the ice from north of Negribreen westwards to Nordenski61dbreen (Storfjorden to Billefjorden) and Holland (1961) reconnoitred the southern margin of Negribreen southwestwards through to Tempelfjorden similarly traversing central Spitsbergen at its narrowest. At northern Hahnfjella, south of the Negribreen outlet, Holland recorded a Triassic succession which, although outside the terrane as defined, may be the only measured section in the general area. Abbreviating somewhat, the succession was recorded thus: 9 m (at summit) thin bedded blue shales with brittle fossiliferous limestone nodules with Arctoceras (cf. A. O'bergi or Flemmingites; Halobia cf. zitteli, Daonella cf. lindstomi etc.; 12m alternating blue shales with concretionary limestones; 12 m paper thin blue shales with occasional iron-stained limestone nodules; 19m blue shale down to limestone shales interbedded with limestone and limestone concretions; 16m thin grey shales; 68 m grey and grey and black shales with Arctoceras sp. and Keyserlingites sp; 46 m thin bedded, grey fawn and grey baked shales to dolerite intrusion about 120m a.s.1. The lithologies and fossil indentifications by L.F. Spath would correlate with the Botneheia and Sticky Keep formations (Sassendalen Group).

5.4.3

Wilhelmoya and Hellwaldfjellet

The importance of Wilhelmoya was perhaps first realised by de Geer (1923) who reported a succession through Early Kimmeridgian, late Lias, latest Triassic and Carnian strata. This was used and discussed by Frebold in his 1935 synthesis and notably Arkell (1956). From a visit by an Oxford party in 1951 Holland (1961) described a sequence of 13 beds. The rocks were described in detail but the fossils identified, mostly bivalves, left the ages indeterminate. The relation between this work, that of De Geer and the opinion of

78

CHAPTER 5

Fig. 5.2. Geological map of eastern Ny Friesland, with representative cross-sections, showing the distribution of Carboniferous and Permian deposits (rearranged after Cutbill 1968).

EASTERN SVALBARD PLATFORM Frebold were discussed. The undoubted Jurassic above Triassic strata here led Sandford to postulate Jurassic rocks at the top of the Triassic succession in Nordaustlandet. In 1961 the section was reconnoitred by a party commissioned by American Overseas Petroleum Limited (Amoseas) and was noted in Buchan et al. (1965, Section JDL21). Klubov (1965) first reported Rhaetian (beds 23-27) in his succession ranging from Carnian to Kimmeridgian rocks from the top of Wilhelmoya. However, his measured succession for the island is not supported by later work possibly because he did not take account of land slips. Worsley (1973), from visits in 1970 and/or 1971, described the uppermost strata and made a case for a new Wilhelm~ya Formation to include similar strata in Hopen and the Brentskardhaugen Bed of Spitsbergen. Smith (1975) described the whole in situ section on the island from a survey with CSE in 1969. He incorporated Worsley's new unit name but as a member within the De Geerdalen Formation which had already been defined to include the Brentskardhaugen Bed at the top. Accordingly in Wilhelmoya and Hellwaldfjellet he named the rest of the De Geerdalen Formation, i.e. above the Tschermakfjellet Formation, as another member (Uleneset) 254 m thick. However, the case is argued by Worsley & Heintz (1977) that the De Geerdalen Formation should be redefined and reduced so as to allow this new formation above it. A consequence is that the reduced De Geerdalen Formation is indeed Smith's Ulaneset Member which no longer needs that name, the Kapp Toscana group thus comprising the rocks as originally defined but in three rather than two formations. Both Worsley and Smith visited similar successions from Wilhelmoya and Hellwaldfjellet on the mainland to the southwest. Smith described the whole sections and Worsley the proposed Wilhelmoya Formation. The following description combines the two.

Wilhelmeya and Hellwaldfjeilet. The Hellwaldfjellet section on the mainland is similar, Hellwaldfjellet being only 35 km to the south, so the description is combined, where there are differences the symbols W and H respectively identify which section is referred to. Smith (1975, pp. 486-487) plotted both sections in full.

Agardhfjellet Fm. Black shales with ammonites of Oxfordian to Kimmeridgian age are separated (W) or capped (H) by a dolerite sill. Ammonites from these (W) include tenuilobatus zone of Arkell (1956, p. 505) and would correlate with middle Agardhfjellet Member to the east (Parker 1967). Klubov (1965a, 1970) reported a bed of clay with belemnites and two foraminiferal assemblages: Bajocian-Bathonian and Callovian. His exposure probably represents a slipped mass amongst others from the Agardhfjellet Formation. The total thickness of sediments above is about 10 m (W) and 35 m (H). Wilhelmoya Fm Turalingodden Mbr, 60m (W) 54m (H), named from the slopes above Tumlingodden, mainly comprises friable fine-grained yellowish grey sandstones. The boundary between the Wilhelmoya and Janusfjellet formation is marked by a thin conglomerate of fine quartz pebbles (H). The top 10 m has pockets of phosphorite nodules including Toarcian fossils similar to those found in the fauna of the Brentskardhaugen Bed. 28m sandstones with a basal pebble bed and winnowed fossils (including belemnites) but absence of plant fossils contrasts with the lower sandstone. A 4 m bed of clay 30 m from the base. Thin black coal lenses and black shales occur within the lower 28 m with tree trunks up to 20cm thick in a metre section are preserved within sandstone concretions. Thin sandstone layers and pockets of quartz and chert pebbles. About 10m from the base is a cliff of well-consolidated sandstone with tabular cross-bedding which indicates westwards sediment transport. Transitional Mbr, 33 m (W) 5 m (H). Dark yellow friable flaggy siltstones with intercalated beds of more resistant cliff-forming olive flags (which weather purple) dominate the upper part and decrease downwards. Harder beds contain mud flake conglomerates, mica and plant debris. The upper boundary is obscured because of the soft overlying beds. Bjornbogen Mbr, 19m (W) 33m (H), named for the bay on the south of Wilhelmoya, is formed of thick dark grey shale which contains winnowed

79

interbeds of plesiosaur bones. Clay ironstones occur with a rich bivalve fauna. Basal Mbr, 7 m (w), is of sandstone. The base of the formation (W only) is marked by a bed with pebbles, sandy limestones, phosphorites and quartzites in a ferruginous silty limestone matrix (W & H). For reference purposes it would have been more convenient to include the Transitional Member as a division in the Tumlingodden Member and the Basal Member as basal beds of the Bjarnbogen Member and this was done later. De Geerflalen Fro, 384 m (W), 401 (H). The thickness includes a 10 to 30 m dolerite sill. The rocks were described by Klubov (1965). They consist predominantly of siltstone and fine-grained sandstone with occasional beds of better-cemented, sometimes calcareous, coarser sandstone. The upper 154 m contains several horizons of shell fragment limestone. Carbonaceous plant material and thin coal seams occur in the lower 200 m. At the base of the Formation is a prominent sandstone bed above the siltstones and shales of the Tschermakfjellet Formation. Invertebrate fossils are rare. Klubov recorded bivalves Lima, Megalodon, Ostrea and Mytilus of shallow marine or non-marine conditions and suggested a Norian-Carnian boundary 221 m from the base of the formation. However, Smith's palynological evidence suggests that the strata are largely Norian. The formation at Hellwaldfjellet is generally sandier, less consolidated and without shell fragments and so less distinct from the Wilhelmoya Fm, (Smith 1975). Of 20 or more samples through the whole succession investigated palynologically in 1961 and 1969 only three gave significant results and these came from the De Geerdalen Formation roughly 337m 166m and 73m from the base of the formation. They were all concluded to be of Norian age (Smith 1975) and to compare with the lower part of the Iversenfjellet Formation of Hopen. Tsehermakfjellet Fm 34+ m to SL (W), ?70 m (H). Siltstones with siderite concretions and Halobia bivalves occur in a disconnected outcrop (H) and from near the base (W) Klubov reported Nathorstites spp. and Halobia zitteli, and higher up Sirenites cf. nanseni, all of which confirm a similar age for the strata. A discussion of these and other finds with conflicting assessments conclude with an Early Carnian estimated age for the formation in Withelmoya (Smith 1975). Botneheia Fro. An exposure of a few metres at the shore by Hellwaldfjellet of silty shale yielded ammonites in 1969: ?Gymnotoceras and ?Hollandites with bivalves indicating an Anisian age (Smith 1975).

5.4.4

Islands of Hinlopenstretet

Whereas Wilhelmoya preserves a Mesozoic succession with incidental dolerite sills, all the other (much smaller) islands, except one between Spitsbergen and Nordaustlandet, have been eroded to the extent that only their igneous rocks are seen. The exception is the largest of the islands, Wahlbergoya where two Permo-Carboniferous outcrops appear on the 1:500 000 map of Hjelle & Lauritzen 3G (1982). Moreover, Korchinskaya (1972a) identified the Arctoceras blomstrandi zone of Spathian age on the island. Tyrrell & Sandford (1933) described many of the known dolerite occurrences and noted that opposite the largest sill in the coast south of Kapp Fanshawe are islands which may well be an extension of it. They suggested that these are fragments of a huge laccolith, possibly of cedar tree type. On and off the Nordaustlandet coast are the massive intrusions at Diabastangen (Hyperite Point) and the Gylden islands. Some dolerite islands further south are surrounded by deep water and form an irregular incomplete ring. This and other arrangements suggest that the islands may be relics of vertically sided intrusions and not irregularly sunken sills (Tyrrell & Sandford 1933, p. 292).

5.4.5

The structure

The dominant feature of this area is the western boundary which is the Lomfjorden (Agardhbukta) Fault Zone and the Hecla Hock

80

CHAPTER 5

synclinorium which is occupied by the strait separating Spitsbergen and Nordaustlandet. Otherwise the platform strata are generally flat-lying.

5.5

Southwestern Nordaustlandet

Nordaustlandet is mostly covered by ice and the exposures are mainly coastal. The platform succession is exposed only in the southwest sector of the island, almost all south of Wahlenbergfjorden. The same three rock types are distinctive from the air namely the black dolerite intrusions, the less resistant dark coloured Triassic strata and the paler harder Permian and Carboniferous strata. Figure 5.3 summarizes the outcrops from a number of independent investigations.

5.5.1

Earlier work

Because it was relatively easy to distinguish Triassic and Permian and/or Carboniferous strata the approximate occurrences were

already plotted as on the maps of Nathorst (1910), Kulling (1934), Frebold (1935) and Orvin (1940). However little was published of the stratigraphy till later. Triassic material from the earliest known outcrops at Torellneset collected in 1931 comprised Saurian remains, bivalves and ammonites (Kulling 1932, 1934). The molluscs were identified by E. T. Tozer and reported briefly by Tozer & Parker (1968) and more fully later (Tozer 1973). These identified late Scythian and Anisian ages. Oxford parties on expeditions to Nordaustlandet in 1923 (Sandford 1926), 1949, 1951 and 1953 described both Hecla Hoek and younger rocks (Thompson 1953; Holland 1961). Of the latter the reports of observations by glaciologists interpreted by Sandford (1963) establish a clear unconformity at Idunfjellet where Late Carboniferous and Permian strata rest on Hecla Hoek rocks. This together with a small outcrop of ?Carboniferous sandstones at Brageneset to the west is the only occurrence of the younger rocks north of Wahlenbergfjorden. South of that fjord and at its mouth De Geer (1923) had reported 200m of Productus Limestone overlying 42 m of Spirifer Limestone. Holland, in a posthumous work edited by Sandford (1961), described Mesozoic and Late Paleozoic rocks in both northeastern Spitsbergen and Nordaustlandet. These Permo-Carboniferous strata

Fig. 5.3. Geological map of southwestern Nordaustlandet showing the known extent of Phanerozoic outcrops. Key to numbered localities: (1) Bodleybukta; (2) Eltonbreen; (3) Ericabreen; (4) Mariebreen; (5) Palanderbreen; (6) Rosenthalbreen; (7) Svartberget; (8) Torellnesfjellet; (9) Winsnesbreen. Compiled from Geological Map of Svalbard 1:500 000 sheets 3G (Hjelle & Lauritzen 1982) and 4G (Lauritzen & Ohta 1984) and from SKS Upper Carboniferous Report Map 3a (Dallman et al. 1996).

EASTERN SVALBARD PLATFORM

Kapp Toscana Grp (?) Wilhelmoya Fro. It is not impossible that this formation is represented at the highest part of the succession at Torrellnesfjellet which was inaccessible to Lowell (1968) owing to ice cover. Sandford in Thompson (1953) and in Holland (1961) suggested the possibility that the highest strata might be Jurassic, on the basis of the presence of black shales at Torellnesfjellet and lithological comparison with samples from Wilhelmoya. If this were so, however, the De Geerdalen Formation might be exceptionally thin. De Geerdalen Fm. 40?+50m. Lowell 1968 described the top of his succession as largely sandstone scree: grey brown, some slightly greenish, faintly limonitic calcareous, finely laminated and platy. Sassendalen Gp Barentsoya Fro. 118 m Lowell 1968 described a uniform sequence of grey shale with thin platy beds of siltstone weathering brown to yellow which are calcareous with 'occasional fontainbleau' structure (i.e. with matrix of larger enveloping calcite crystals). He reported the presence of brachiopods. Cutbill (CSE) had already identified these rocks as belonging to the Sassendalen Group. The name Barentsoya Formation is applied here because, with the exception of some interbedded limestone with chert in the lower 20m the whole was described as undifferentiated. In so far as the three formations, which define the Sassendalen Group in Central Spitsbergen, are not distinctive here, the Barentsoya Formation is applied from Barentsoya and Edgeoya where the three formations also are not readily distinguished. Kulling's collection was from two levels and he suggested that the upper level was the Upper Saurian Niveau. The underlying level 'Daonella Niveau' was exclusively of bivalves (Posidonia arenea Tozer) which is restricted to the later Spathian Zone (Keyserlingites subrobustus zone). This correlates with the Sticky Keep Formation of Spitsbergen. Fossils from Kulling's upper horizon of typical Botneheia facies include nine ammonite species and the ichthyosaur Phalardon nordenskioldi was identified by Stensi6 (Kulling 1932). These give a certain middle Anisian age and possibly an Early Anisian age also. In any case they confirm correlation with the Botneheia Formation in Spitsbergen. Tempelfjorden Gp Kapp Starostin Fm. Lauritzen (1981) distinguished two limestone members in the otherwise siliceous sequence, the basal Voringen Mbr (recognised elsewhere), and the Palanderbukta Mbr (Fig. 5.4). This led to the naming of the remainder of the alternating normal siliceous sequence with the names from central Spitsbergen thus: Hovtinden Mbr: 27 m of yellow and grey cherts at the top with subordinate sandstones; glauconitic. Then predominantly sparitic limestones, in places dolomitized, with chert bands and nodules. Palanderbukta Mbr: 17.5m characterized by glauconitic and fossiliferous limestones, with pure chert beds. Svenskeega Mbr: 37.5m of chert-dominated sequence with relicts of calcareous beds or nodules. Intraformational conglomerates and erosion horizons at the top.

in N o r d a u s t l a n d e t were described f r o m m a n y localities and m a p p e d as such with a large o u t c r o p occupying m o s t of Gustav A d o l f L a n d (south of W a h l e n b e r g f j o r d e n ) and excepting the Triassic o u t c r o p extending eastwards a n d inland f r o m Torellneset. There the succession was described generally as (4)

Upper chert, Marble and Limestone Series with Stenopora ramosa 30+ m (3) The Rough Limestones, with S. ramosa, Spiriferella cf. lita etc. 40 m. (2) The Cliff Limestones, with Spiriferella cf. polaris, etc. 55 m (1) The Calciferous Sandstone Series with Productus (Horridonia) timanicus, 45 m. Base not seen. Fuller descriptions of each of these units was given with fossil lists for each but lacking detailed maps or sections this pioneer reconnaissance is difficult to follow. The Mesozoic results were largely published in T h o m p s o n (1953) with a postscript by Sandford. The next field w o r k was in the early 1960s w h e n CSE c o o p e r a t e d with A m o s e a s using helicopter support. Cutbill extended his study of P e r m i a n and C a r b o n i f e r o u s stratigraphy. H e n o t e d Triassic successions comprising u p p e r m o s t strata which he regarded as K a p p T o s c a n a and a lower 150m of shales as Sassendalen G r o u p above K a p p Starostin (especially Voringen M e m b e r ) overlying the G i p s h u k e n F o r m a t i o n , with basal Hftrb a r d b r e e n M e m b e r (Cutbill & Challinor 1965). Lowell (1968) of A m o s c a s filled in m o r e detail a n d m e a s u r e d two Triassic and P e r m i a n sections as well as giving a m o r e detailed o u t c r o p map. Lauritzen (1981), w o r k i n g f r o m Wahlenbergfj orden, addressed only the Late Paleozoic succession a n d with m o r e m e a s u r e d sections. This resulted i.a. in extending the age of the lower p a r t of the succession back to M o s c o v i a n time. His w o r k was also incorporated in the 1:500 000 geological m a p 4 G (Lauritzen & O h t a 1984). M a n g e r u d & K o n i e c k i (1991), investigating the P e r m i a n rocks of N o r d a u s t l a n d e t palynologically, r e c o r d e d sixty forms ranging mostly in the ?Gipsdalen G r o u p . H o w e v e r , little was a d d e d to previous k n o w l e d g e as to their age. Nevertheless a useful synthesis o f m e a s u r e d sections by M. B. E d w a r d s with those of Lowell & Lauritzen (already m e n t i o n e d ) shows the position of their samples. A t the same time an i m p r o v e d sketch m a p of W a h l e n b e r g e t and P a l a n d e r b u k t a distinguished clearly the T e m p l e f j o r d e n a n d Gipsdalen G r o u p outcrops.

5.5.2

81

Stratal succession

K n o w l e d g e has c o m e s o m e w h a t piecemeal. The succession is s u m m a r i z e d in Fig. 5.4.

Nordaustlandet Cutbill & Challinor (1965) KAPPTOSCANA (?~chermakqtFm)

This work (following SKS 1996)

Lauritzen 1981

Lowell1968

De Geerdalen Fm

KappToscana Fm

Barentsoya Fm

SASSENDALEN GROUP (undifferentiated)

Kapp

Kapp

Starostin

Starostin

Svenskeegga Mbr

Fm

Voringen Mbr

Palanderbukta Mbr

Kapp Starostin

Svenskeegga Mbr

Fm

Gipshuken Fm Zeipelodden Mbr

Carbonate Unit

DICKSON LAND

Idunfjellet Mbr Nordenski61dbreen

H&rbardbreen Mbr

TEMPELFJORDEN GP

Voringen Mbr

Gipshuken Fm Gipshuken Fm

SASSENDALEN GP

Hovtinden Mbr

Hovtinden Mbr

Fm

KAPP TOSCANA GP

Fm

Idunfjellet Fm ]

Wordiekammen Fm

H&rbardbreen H&rbardbreen Mbr L Fm

SUBGP

CAMPBELLRYGGEN SUBGP J

Fig. 5.4. Stratigraphical schemes for Permian and Triassic units of Nordaustlandet.

82

CHAPTER 5

Voringen Mbr: 9 m of sandy biosparite with conglomerate layers. Erosion surfaces, cross-bedding and bioturbation are common. Coal fragments occur at the base, and fossils are abundant. It rests on a clearly eroded surface of Gipshuken Fm. Lauritzen interpreted the Voringen Mbr as a transgressive shallow marine unit, probably near-shore as indicated by erosion surfaces. The change to cherts indicates a switch to an open shelf environment and hence subsidence, but this reverses at the top and into the Palanderbukta Member which is once again a shallow marine unit with periods of erosion. Basin deepening occurred at the transition to the Hovtinden Member with biosparite deposition and then further cherts, which are commonly spiculitic.

Gipsdalen Gp Gipshnken Fro. Cutbill & Challinor (1965) described the Gipshuken Fm with the H~trbardbreen Mbr (Formation) at its base. Lowell (1968) followed this section referring to the rocks between that member and the Kapp Starostin Fm as the Carbonate Unit. This might have merited a separate name had not Lauritzen (1981) shown that biostratigraphically the lower part of the Carbonate Unit belonged to the Nordenski61dbreen Fm (Wordiekammen + Minkinfjellet fms) and named it the Idunfjellet Mbr (see below). Thus the Gipshuken Fm is equivalent only to the upper part of Lowell's Carbonate Unit. Lauritzen (1981) described the formation from Zeipelfjella (Fig. 5.5.2) and Zeipelodden in the Wahlenbergfjorden area. The formation reaches a maximum thickness of 121 m there, with a clearly identifiable member (the Zeipelodden Mbr) at the base. The member is a 8 m thick unit of limestone breccias and laminated algal limestones with algal mats, crusts and chert nodules. The remainder of the formation consists of well-bedded limestones and dolomites with chert nodules. He interpreted the formation as a lagoonal deposits with some tidal influence, especially the basal member which was probably intertidal. Mangerud & Konieczny (1991) investigated the palynology of the formation in the area. Although the middle and upper parts did not yield age diagnostic forms, the lower part was given a Sakmarian to Artinskian age along with the underlying Idunfjellet Fm. Idunfjellet Fm (Lauritzen 1981) Up to 150m thick, the Idunfjellet Fm consists of limestones and dolostones with minor sandstones (Fig. 5.4). It is the northeastern equivalent of the Wordiekammen Fm. The carbonates contain chert nodules; the sandstones cross-bedding and intra-formational conglomerates. The formation was deposited on an open marine shelf, some parts in the inter-tidal zone, with a terrigenous input from a nearby land mass. Periods of non-deposition were common, as the formation represents the entire late Carboniferous to early Permian time-span. Fossils have mostly been destroyed by dolomitization; however some from the base indicate a Moscovian age for that level and palynomorphs indicate a Sakmarian-Artinskian age. The 135.4 m thick type section consists of limestones and dolomites with a quartz content varying from 6 to 21%, especially in the lower l0 m, which are well-bedded sandy dolostones. The sand is the same grain size as in the Hftrbardbreen Fm below. Chert nodules are abundant in some beds, which preserve bioclastic remains. Silicification tends to follow certain horizons and the cherts are sometimes associated with crusts of hematite and thin layers of goethite. Erosive sandstones occur, containing thin intraformational conglomerates and cross-bedded units. Dolomitization has destroyed most fossil fragments, except in some horizons where they are abundant, especially 10m above the base in a distinctive partly dolomitized and silicified biosparite which contains a variety of fossils. Brachiopods, gastropods, echinoderms, cephalopods, foraminifers and ostracodes occur. The biosparite horizon ! 0 m above the base has been dated as Moscovian on the basis of the foraminifera Palaeojusulina trianguliformis and several Bradyina species (Lauritzen 1981). Palynological investigations of the formation indicate a Sakmarian to Artinskian age (Mangerud & Konieczny 1991), and hence it would appear to have a long time span. This is consistent with the common erosion surfaces and intraformational conglomerates, which imply reworking and periods of non-deposition. Also, the overlying Gipshuken and Kapp Starostin fms have been correlated with the same formations in the rest of Svalbard on the basis of lithology. Thus, the Idunfjellet Fm and the basal Hftrbardbreen Fm together appear to represent the Wordiekammen and Minkinfjellet fms respectively. Lowell (1968) described his Carboniferous unit (Idunfjellet and Gipshuken Fro, i.e. above the Dickson Land Subgroup) as being a condensed sequence compared with the much thicker equivalent succession in Central Spitsbergen. This argument is strengthened by the large age span for these rocks as indicated above. However, Lowell followed Cutbill when including these rocks within the Gipsdalen Formation.

Fig. 5.5. Sketch map of Svenskoya, Kongsoya and Abeloya (redrawn with permission of Cambridge University Press from Smith et al. 1976).

H~rbardbreen Fm. This unit at the base of the Permo-Carboniferous sequence in the Nordaustlandet area, was, in the absence of datable fossils, assigned to the base of the Gipshuken Fm by Cutbill & Challinor (1965). Lauritzen (1981) redefined it, after detailed studies, in the section at Idunfjellet on the opposite side of Wahlenbergfjorden from H~rbardbreen. It lies conformably below the Idunfjellet Mbr and its base is a strong angular unconformity with pre-Devonian (Hecla Hoek) rocks. There is evidence that the basal conglomerates are laterally replaced westwards and on the south side of Wahlenbergfjorden by sandstones (e.g. at Hftrbardbreen). The formation is a 15.5 m thick unit, consisting of light, yellowish-grey, fine-medium quartzitic sandstones with some conglomeratic horizons. Crossbedding is locally present and the whole unit becomes finer upwards. There is a basal conglomerate 8m thick which unconformably overlies the preDevonian peneplain surface. The clasts are mostly of dolomitic mudstones,

Fig. 5.6. Sketch map of Svenskoya showing principal topographic features and geology (redrawn with permission of Cambridge University Press from Smith et al. 1976).

EASTERN SVALBARD PLATFORM but also clasts of the underlying red mudstone commonly occur. The conglomerates appear to be locally developed, with lateral replacement by sandstone. The formation has no fossil record, but a Moscovian transgression has been described in Ny Friesland and central Spitsbergen (Cutbill & Challinor 1965) and this unit may therefore be the lateral equivalent of the base of the Campbellryggen Subgroup there.

5.6

Kong Karls Land

Kong Karls Land is a group of three main islands (Fig. 5.5) and many smaller ones and is the easternmost substantial land in the Svalbard archipelago. It is generally surrounded by sea ice even through the summer so that visits have been limited either by ship in favourable seasons or more recently by helicopters from icestrengthened ships. Apart from the ubiquitous Quaternary cover the rocks are entirely Mesozoic. Svenskoya is the westernmost island, 20 km by 6 km (Fig. 5.6). Most of the island is of beach deposits but there is an axial N-S ridge the length of the island rising from Kukenthalfjellet, 180 m in the south to Dun~rfjellet, 250 m in the north. The main island Kongsoya (Fig. 5.7) is central and about 40 by 8 km, but of irregular outline. It divides naturally into five terrains from west to east (1) a western complex of fiat topped hills, (2) a neck of low ground, raised beaches and blown sand, (3) a low lying plain of basalt, (4) a low hilly area of basalt with a small ice cap, Rundisen, and (5) one main hill (Johnsenberget) sloping down from 240 m to low cliffs at the east coast. The eastern irregular island, Abeloya is not more than 4 k m across, mostly less than 5 m above sea level and formed of basalt.

5.6.1

Apart from occasional visits the first, and for many years the only, proper geological investigation was by the Swedish expedition of 1898 led by Nathorst (1901, 1910; Pompeckj 1899; Bliithgen 1936) (Fig. 5.8). This gave a topographic base and a geologic outline. The uppermost strata are basalts and plant beds. These were shown to truncate and overlie three blocks, normally faulted, from west to

KONGSE

east: (1) Eastern Svenskoya of Volgian, Kimmeridgian, Oxfordian strata; (2) A central block (eastern Svenskoya and western Kongsoya) of Callovian over Bathonian strata and (3) the main body of Kongseya of Valanginian, Late and Early Volgian, Kimmeridgian strata. In 1930 the Norwegian expedition to Franz Josef Land in passing confirmed that Abeloya was entirely igneous. A new era in geological exploration of these often ice-bounded islands began with the use of helicopters. In 1969 a Cambridge reconnaissance of the islands of eastern Svalbard was supported by Norske Fina. Sections were recorded at most cliff exposures of Kongs Karls Land and the structure and stratigraphy were described (Smith et al. 1976). Norsk Polarinstitutt geologists visited the islands in 1973 and they found an exposure lower than previously recorded in northwest Kongsoya (Worsley & Heintz 1977). This was supplemented by palynostratigraphy (Bjaerke 1977, Bjaerke & Dypvik 1977). The material collected in 1969 continued to yield results (e.g. Rawson 1982; Doyle 1986, 1987; Doyle & Kelly 1988; Ditchfield, 1997). The rock units of Kong Karls Land were defined by Smith et al. (1976) and related to those of Pompeckj (1899), Nathorst (1901) and Bliithgen (1936), with one addition and one modification proposed by Worsley & Heintz (1977) as shown in Fig. 5.8. Their distribution is shown on the maps of Svenskeya (Fig. 5.6) and Kongseya (Fig. 5.7). The strata were described and measured in 15 or more sections (Smith et al. 1976) Because of the variety of facies including lavas even within one island the units were named independently as members within three distinct units. The Kong Karls Land, Kongseya and Svenskoya formations. However the Wilhelmoya Formation (Worsley 1973) has priority over the name Svenskoya and is applied here.

5.6.2

Earlier work

83

Stratal succession

Adventdalen Group. The correlation of the principal stratigraphic sections of Svenskoya are given in Fig. 5.9 and of Kongsoya in Fig. 5.10. Kong Karls Land Fm. This is the uppermost unit comprising plant bearing sandstones interbedded with lavas. It approximates stratigraphically to the Helvetiafjellet Formation in Spitsbergen which also contains evidence of vulcanicity and has been taken to be of Barremian age (Parker 1967).

A ~

Ose~

Notcl~s~ynlim

Kaoo Otnva

..

0 I

~

5 =

i

10 k m I

, - -

Fig. 5.7. Sketch map of Kongsoya showing principal topographic features and geology (redrawn with permission of Cambridge University Press from Smith et al. 1976).

84

CHAPTER 5

Schemes of rock units Early age estimates

Pompeckj & Nathorst Smith, Harland, Hughes & Picton 1976 with proposals* by Worsley & Heintz 1977 1899 1901 KONG KARLS LAND

SVENSKOYA

Current age estimates

KONGSOYA ~ X,BELWESTERN EASTERN OYA

13 basalt Kong

Member

H&rfagrehaugen Member

Johnsenberget Member

Karls

sandstone

sandstone

sandstone

Land Formation

65.5 m (Beds 10 & 12)

14 m (Beds 10 & 12)

30 m (Bed 10)

K0kenthalfjellet

12 plant bearing layer with Phoenocopsis Neocomian

11 basalt

c0 Barremian

10 plant bearing layer

Late

Volgian I=nrly Early Kimmeridgian

g Bed with Aucella keyserlingi 8 Bed withAucelta fischeriana and A. volg,,ensis eto 7 Bed withA, pallasi 6 Bed with Cardioceras. andAucella sp.

s./.

Tordenskjoldberget Member limestone 30 m (Bed 9)

~" ~ c

Kongs~ya Formation

5 Bed with A. bronni vat. lata Oxfordian Middle & Late 4 Bed with Cadoceras and belemnites Callovian - 3 Bed with Macrocephalites (=Arcticoceras Early arcticus) & belemnite~ Late

Fig. 5.8. Stratigraphic schemes of rock units with age estimates. In this work the units are described as by Smith et al. (1976) and accepted as shown, but with the later proposals by Worsley & Heintz 0977) for the Wilhelmeya Formation (rather than the Svenskoya Fm) and the Kapp Koberg Member.

Bathonian

Bed with Pseudomonotis etc.

sand and sandstone

no fossils

Dunerfjellet Member

upr

shale

Iwr

(upper & lower) 6O m (Beds 3-7)

~ ~

~ ~

~ = "~ ~

~

~

~

Nordaustpynten Member

Kimmeridgian Oxfordian Callovian Bathonian

?50 _m_(_Be_d_ 9_L _ shale

?150 m (Bed 8)

s.I.

Bajocian

Member clay 75 m (Bed 4) Sjergrenfjellet Member

sandstone (Beds 1 & 2)

sandstone

Arnesodden Bed

*Kapp Koberg Member

shale

Hauterivian Valanginian Berriasian Tithonian

Passet

Mohnhegda Member

_

~

Retziusfjellet Member shale 75+ m (Beds 6-7)

Upper part of Kongseya Formation

Aalenian Toarcian Ptiensbachian ?Sinemurian ?Hettangian

Rhaetian

MOHNH~GDA k'0KEI,fI'HALFJELLET

DUNI~RFJELLET

bQsatt

T

?-"v

i

7t i

200 m

-r T

i

u

x

!":" ," ;

:...i/..:.1 K O W - n t ~

9 , -~ oi

Fig. 5.9. Correlation of the principal stratigraphic sections on Svenskaya (redrawn with permission of Cambridge University Press from Smith et al. 1976).

Lend Fm

~

Fm

Member

Fm

;.4

\1

100

KongKor~

Member

5o 0

i

2

3

4

I

I

I

I

I

5kin I

ArnesenoddenBed

It includes units 10 to 13 of Nathorst but there are more lavas than he listed. The three members each represent the entire formation in a particular area. The reference section at Mohnhogda in Svenskoya may be taken as the type for the Formation. Kiikentbalfjellet (sandstone and basalt) Mbr, 65 m at Ktikenthalfjellet the southernmost mountain of Svenskoya comprises a variable sequence of mainly arenaceous sediment with basalt layers which are units 10 and 12 of Nathorst (1910, p. 362). 5.1 m basalt, lava flow, vesicular in the basal 2 m; 6.1 m sandstone with some shale and compressed plant remains; 2 m coal seam with brown clay; 2 m sandstone, fine, weathering brown, with calcareous streaks; 19.6m sandstone, soft and white, with irregular clay laminae; 99 m basalt, massive, probably a sill; 1.4 m brown sandstone; 10.8m sandstone, soft white, with a thick discontinuous body of massive brown weathering medium sandstone probably a channel fill; The sill meets the lava in the west (as was noted by Nathorst). Each of the six intermediate sections measured is different (Smith et al. p. 205). At the northernmost mountain Mohnhogda (20 km to the north) two basaltic

;RA

lava flows, 17.4 and 44m respectively, cap the mountain with 10.3m sandstone between and 7.3 m in sandstone beneath. They are not separated by sandstone to the south at Dun6rfjellet. In each case the topmost lava forms a protective covering to the softer sandstones beneath and only a narrow ridge remains9 Nathorst recorded Cladophlebis sp. Taeniopteris or Anamozamites, Podozamites laneeolatus pichwaldi and Pinus sp. H~rfagrehaugen (sandstone and basalt) Mbr of western Kongsoya. The type section is at Tordenskjoldberget and is confused by several slipped masses, referred to as Belemnitkullarna (belemnite mounds) by Nathorst, with mixed origins. This member comprises 14m mainly of sandstone beneath a thinner basalt lava. Loose to unconsolidated sandstone, (medium to coarse) siltstone and shale make up the sedimentary part. Coal and carbonaceous beds are characteristic and two lava flows (generally in contact) cap the mountain. Compressed plant remains have well preserved cuticles. Petrified wood occurs, several trunks being up to 1 m long just beneath the basalt, and some fragments were found in the basalt shot through with siliceous veins. Such material, probably from here, was described by Gothan (1907) who commented that the excellent preservation could be attributed to the

EASTERN SVALBARD P L A T F O R M PASSEr

SJIZ~.-,RENFJELLET

TORDENSKJOLDBERGET

W

E

..

..

7-" v I basalt

-

Vv

"-,'1 -

v

basal1

I

100

.. Kong Karls Lend Fm

200 m SJcrgrenllellet M e m b e r

-

85

v

_ --__

x ? dolerite X X

Rotzlu,~ot _

blombor

Kono~o Fm

svom~qo Fm

?

/o

0

1

2

3

4

I

I

I

I

I

5 km

I

overriding lava. He identified the following species which included new taxa suggesting at first a Late Jurassic age but later (1910) changed to early Cretaceous: Phyllocladoxylon sp; Xenoxylon phyllocladoides Gothan; Cupressinoxylon cf. mcgeei Knowlton; Cedroxylon cedroides Gothan; Cedroxylon transiens n.sp; Protopiceoxylon exstinctum Gothan. From evidence in Kong Karls Land, a Valanginian or later age is deduced. By lithological analogy with Spitsbergen the age may be Barremian. Johansenberget (sandstone and basalt) Mbr of eastern Kongsoya. At the top of the hill are 30 m of sediment underlying 20 m of basalt. The sediments include Nathorst's bed 10. Sandstones with plant remains are conglomeratic in part. In conclusion, throughout the islands the basalts are better exposed than the sediments and generally at least two lava flows can be traced either in contact with each other or separated by sediment. Reconnaissance investigation of the Kong Karls Land Fm palynomorphs gave three significant results. (i) Rhaeto-Liassic spore and pollen types occur and suggest that erosion of the earlier strata contributed to the sediments. (ii) Lack of angiosperm pollen indicated an age earlier then Albian. (iii) The main flora is of long range species, not older than latest Jurassic, and entirely consistent with Early Cretaceous. All characteristics indicate a non-marine environment for the Kong Karls Land Formation. Kongsoya Fro. This unit is of typically marine facies dominated by shales rather than sandstones. It would thus appear to correspond stratigraphically to the Janusfjellet Subgroup of Spitsbergen. The particularly well-preserved Arcticoceras fauna in the lower part of the formation is of mid-Bathonian age (Rawson 1982). The early record of Arctocephalites arcticus (Newton) in Kong Karls Land was of Early Bathonian age (Pompeckj 1899; Arkell 1956) but has not been collected recently. These Bathonian faunas may be compared with the fuller East Greenland sequence (Callomon 1994). Dnn~rfjeUet (shale) Mbr, 6 3 + m (in Svenskoya). A shale unit, with distinctive upper and lower divisions, but the base is not seen. Upper division, 19m tough shale with bivalves Buchia, ammonites Amoeboceras (Amoebites) of early Kimmeridgian age and fish fragments probably including the new species Leptolepis nathorsti (Woodward 1900). Lower division, 42+ m (bottom not seen) is of weathered dark grey shales with small belemnites and ammonites preserved in pyrite: Cardioceras cf. cordatum (Late Oxfordian) and Arcticoceras and Cadoceras (Late Bathonian or initial Callovian). Facies are variable, even in the small outcrop on Svenskoya, and include northeast of Kiikenthalfjellet a unit 47 m with horizons of clay ironstone, similar to Janusfjellet, where fish fragments characterize the upper part and belemmites and pyritized ammonites the lower part. At Mohnhogda the member is represented by 20 m of dark shale. No macrofossils were recorded there but organic microplankton indicate a marine environment. The thickness was probably reduced here by preKtikenthalfjellet Member erosion. Tordenskjoldberget (limestone) Mbr, 30 m in southwestern Kongsoya. This is of limited extent known only from near the type locality 1.5kin east of Passet and was estimated by Bltithgen (1936, p. 59) to be of Early and Mid-Valanginian age. To the east it is rich in belemnites which weather

;RAI

Fig. 5.10. Correlation of the principal stratigraphic sections on Kongsoya (redrawn with permission of Cambridge University Press from Smith et al. 1976).

out of mounds formed by landslips. To the west it is overstepped by the Kong Karls Land Formation. One of the few occurrences of extrusive igneous rocks below the Kong Karls Land Formation is seen within this member as bright red weathering pumice including fragments of baked sediment. This Valanginian eruption is the earliest evidence of igneous activity in western Kongsoya. Upper division (15m) shales, siltstones with dark brown weathering ironstone nodules and a calcareous horizon, 4 m above the base with bivalves. Lower division (15 m) of white and light yellow loosely cemented calcareous sandstone consisting of inoceramid type fragments. Complete Buchia keyserlingi (Lahusen) are common together with abundant belemnite guards. The solitary coral ?Theococyathus nathorsti (Lindstr6m 1900) was recorded. Retziusfjellet (shale) Mbr, 7 5 + m in western Kongsoya. This member correlates with the upper division of the Dun~rfjellet Member of Svenskoya. At the type section it rests on the thin orange-weathering hardground at the top of the Passet Member. It consists of grey and black shales with occasional horizons of nodules weathering red or yellow. At Retziusfjellet in particular some concretions are large, some septarian, and many with ammonites, belemnites (with phragmocones) and bivalves in full relief. The youngest ammonite fauna consists of Amoeboceras (Amoebites) kitchini and Aulacostephanus (Xenostephanus), probably of Early Kimmeridgian mutabilis zone, and Amoeboceras with Rasenia probably cymadoce zone and flattened Amoeboceras (Hoplocardioceras). Mid- or Late Callovian ages are implied by Longaeviceras? and Quenstedtoceras s.1. (e.g. Eboraciceras) The oldest confirmed fauna is the Arcticoceras fauna dated as early ishmae zone (mid-Bathonian) by Rawson (1982). The Member is overstepped at Passet by the Kong Karls Land Formation. Passet (clay) Member 65+ m in western Kongsoya, is predominantly of clayey beds, generally unconsolidated and including occasional ironstone nodules and beds of sand or sandstone. It is cut out to the west by the Kong Karls Land Fm (Hgtrfagrehaugen Mbr) and is approximately equivalent to the lower divisions of the Dun~rfjellet Mbr of Svenskoya. It includes occasional ironstone nodules and beds of sand or sandstone and a fauna of small belemnites. Nathorst's estimate of this bed 4 was Mid- to Late Callovian. There is a Sinemurian-Toarcian foraminiferal date (Lofaldli & Nagy 1980); Doyle & Kelly (1988) gave an Aalenian (possibly Toarcian) Bajocian age based on belemnites alone. Eastern Kongsoya In the upper slopes of Johnsenberget clays, siltstones, yellow and green sandstones are exposed with belemnites and bivalves and a calcareous sandstone near the top. These belong to the upper part of the Kongsoya Fm. Nathorst's equivalent (Beds 8 & 9) would suggest an early to Middle Valanginian age for the bivalves. Nordaustpynten (shale) Mbr (?150-200 m), is a black shale also placed in the Kongsoya Fm. It occupies the lower slopes and the extreme eastern sea cliffs of Kongsoya where between two basalt layers, probably extrusive, is a horizon with flattened ammonites and bivalves ?Rasenia/Aulacostephanus with cardioceratids indicate an Early Kimmeridgian age. In the southeastern exposures bright red baked shales mark eruptions, probably volcanic.

86

CHAPTER 5

Wilhelmoya (Svenskoya) Fm. This formation comprises an upper continental sandstone division and the upper part of a lower shale division and occurs the length of Svenskoya, but only in western Kongsoya, being in each case the lowest formation above sea level. The sands are unconsolidated (without cemen0 and of high porosity, a facies not reported in Spitsbergen. Nevertheless there is some similarity in facies and position with the original De Geerdalen Fm, particularly its upper unit, Worsley's Wilhelmoya Fm. However, Worsley & Heintz (1977) acknowledged that the De Geerdalen Formation had been defined to include all rocks up to the "Lias conglomerate'. They reported a lower unit, the Kapp Koberg Member, which usefully extends the Kongsoya sequence downwards. They also recommended to drop the name Svenskoya Formation in favour of Wilbelmoya Formation (Worsley I973) accepted here. Mohnhogda (sandstone) Mbr, 197m in northern Svenskoya is thickest at Mohnhogda where the lowest 50m is largely obscured by loose talus from the sands above. It consists mainly of sandstone or loose sand coloured grey, yellow or brown with occasional interbeds of sandstone bearing fragments of fossil wood. Further south thin pebble horizons occur and at the far south a thin gravel conglomerate. Arnesodden (shale) Bed, 5 m to sea level. This Mack shale and siltstone occurs at the base of the steep sandstone slope and represents the lowest beds exposed in Svenskoya. Sjogrent-jellet(sandstone) Mbr, 130+ m possibly 235 m in western Kongsoya corresponds to the Mohnhogda Member in having poorly consolidated fine sandstone with stringers and interbeds of grey and brown clay, and thin coal seams. Beds of harder sandstone, some weathering orange, and pebbly horizons occur. Plant fragments, wood and lignite were noted at Passet where slump structures were seen in the sands. Kapp Koberg Mbr, 36 m in western Kongsoya. Whereas the above units were all described by Smith et aL (I976). This member was newly defined by Worsley & Heintz (1977) and extends the Kong Karls Land sequence downwards. It is a conspicuous in the cliffexposure near sea level, at the base of a cliff and may have been obscured by ice foot in 1969. The member is a shale, coarsening upwards to sandstones of which the lower 13 m consists of poorly consolidated mudstones with silty interbeds. The friable sandstones with cross-bedding indicate N NW to W directed flow, with similar orientation of the plant fragments. The lower 25 m of the whole section contains occasional vertebrate remains in sideritic beds or in small erosive washout structures. One sandy bed contained a large sideritic concretion with a nearly articulated plesiosaur skeleton. It was partially eroded in the cliff section. Parts of which were collected together with the palynomorphs so providing a marine assemblage. WBhehnmya Fm palynomorphs. The palynomorphs from upper and lower horizons in the higher sandstone units of the Svenskoya Formation were investigated by Smith (Smith et al. 1976) from samples from north and south Svenskoya. Preservation is good. The assemblages almost entirely without marine influence except for occasional microplanton but no dinoflagellates. All the taxa have Rhaeto-Liassic ranges. The assemblages from the upper part of the formation in each locality were similar and correlation was suggested tentatively with Orbells" (1973) two zones (based on sections in England, Sweden and Greenland). The lower samples collected near sea level, approximate to his Rhetopollis zone and the remaining preparations to his Heliosporites zone. With several qualifications enumerated by Smith this could indicate a Triassic-Jurassic boundary somewhere within these sandstone members. A late limit of Sinemurian was suggested and the earliest part is probably Rhaetian. This conclusion is consistent with palynological work by Bjaerke (1977), Bjaerke & Dypvik (1977), and Bjaerke & Manum (1977) and makes it almost certain that the Kapp Koberg Mbr is Rhaetian. Smith made comparisons with Hopen (Smith et ai. 1976), confirmed by Bjaerke & Manum (1977), that the lowest shale unit in Kong Kads Land and the overlying sandstone represent a marine followed by a non-marine sequence very similar to the sequences in Hopen and Wilhelmoya and could thus all be coeval. The age of the Arnesodden shale bed remains uncertain. It could be an extension of the Kapp Koberg Member, but it has not been investigated.

5.7

Barentsoya, E d g e o y a and T u s e n e y a n e

Edgeoya, t00 km from north to south, is the third largest island in the Svalbard archipelago after Spitsbergen and Nordaustlandet. It is nearly half covered by ice which tends to occupy the higher ground rather than concentrate in valley glaciers. Barentsoya at perhaps a quarter of the area is the fourth largest.

Pre-Quaternary strata are remarkably uniform throughout both islands on which Triassic outcrops exceed in area the combined Triassic outcrops of the rest of Svalbard. Exceptional Permian inliers give a base to the Triassic succession and the highest mountains in southern Edgeoya are capped by the youngest s t r a t a - probably Rhaetian, possibly Hettangian. Dolerite sills occur extensively and form the 'thousand islands' (Tusenoyane) scattered throughout an area (the size of Barentsoya) to the south o f Edgeoya. It is convenient to treat the two main islands together.

5.7.1

Earlier work

The southern coast of Edgeeya protected by the dangerous Tuseneyane was probably known from the early expeditions o f Barents from 1959 and shown on a map by Plancius in 1612. The name is for Thomas Edge an English whaler whose visit in 1616 may be the first recorded. Barentsoya was not known to be an island separate from Spitsbergen until the middle of the nineteenth century. It had been k n o w n as Barents Land. Fuller details of this early history entailing the (mainly British and Dutch whaling fleets are given in Place Names o f Svalbard (Norsk Polarinstitutt Skrifter N o 80, 1942). The first geological record is by Keilhau in 1827 and the second by Lamont in 1859 with fossils identified by Salter (Lamont 1860). From Nordenskirld's 1864 expedition material was shown to be Triassic (Lindstrrm 1865). The Russo-Swedish Arc of Meridian Expedition 1899-1901 was the first systematic survey of the western parts of the islands from which Wittenburg (1910) described Triassic faunas and Baeklund (1907) described and interpreted (1921) the dolerite intrusions. Arising from the same Swedish work was De Geer's contribution including these islands in his general account of Svalbard (1910). The Scottish Spitsbergen Syndicate was geologically active after the First World War in several parts of Svalbard in support o f mineral claims, giving rise to several useful publications. In the course of work in Storfjorden, Tyrrell (1933) described sections from the west coasts o f Barents~ya and Edgeoya. This interwar period saw the beginnings of Oxford and Cambridge expeditions including one to Edgeeya led by G. Watkins on which Falcon (1928, later Chief Geologist in British Petroleum) proposed a three-fold division of Triassic strata which has continued to this day. He noted the importance o f the lower unit (the oil shales group). Little was done in these islands geologically until the new stimulus of the search for hydrocarbons beginning about 1960 (e.g. Nagy 1965). At this time also there was renewed interest in describing lithic units in which to relate paleontological records so leading to new systematic schemes o f nomenclature. A distinct Soviet contribution in this episode was the description of the three Permian exposures beneath the Triassic strata, one quite easily seen on the north cast coast of Barentsoya and two minute inliers in the interior of Edgeoya (Klubov 1964, 1965a, b, c). The next significant geological exploration of the islands was in 1969 by two independent groups, one from the Norsk Polarinstitutt, Oslo, (Hood, Nagy & Winsnes 1971) and the other from Cambridge Svalbard Exploration (CSE) in cooperation with Norskefina (throughout eastern Svaibard). Both had the benefit of helicopter support from ice-strengthened ships. In each case research continued from that 1969 basis. Flood, Nagy & Winsnes (197I) published their first results on these islands and Hopen. Their paper included a map of the islands to a scale of 1: 500 000. Edwards (1976) noted growth faults in the Late Triassic unit seen from the air in cliffs at Kvalpynten. Much other Norsk Polarinstitutt work has been concerned with topographic survey and Quaternary studies. Two deep wells were drilled in Edgeoya which CSE investigated (Section 5.7.3 below) one interpretation of which has been published (Shvarts 1985).

EASTERN SVALBARD PLATFORM

No overlying unit remains in these islands. The base of the formation is taken at the first prominent sandstone (thicker than 1 cm) above the underlying shales of the Tschermakfjellet Formation. On this basis the boundary is transgressive and presumably correspondingly diachronous. The formation is at least 400 m in Edgeoya and 240 m in Barentsoya. It is of, generally flaggy, sandstones with subordinate siltstones, sandy and silty buff shales with rarer black and grey shales, thin coal seams ironstone and oolitic, micritic and shelly limestone beds. Flood et al. (1971) reported that the sand grains rarely exceed 0.5 mm with an average composition of quartz 40%, rock fragments 30%, cherts 15%, alkali feldspar 10%, other grains (including muscovite and plagioclase) 5%. They regarded euhedral quartz grains as suggesting derivation from the Precambrian quartz-porphyries of Nordaustlandet, but Lock et al. considered the crystal shapes as authigenic. Cement is generally of calcite, often sparry with carbonate mud. Organic remains include fossil plants and some bivalves (including oysters in some beds). Klubov (1965a) recorded a specimen of Nathorstites at the base of the formation at Negerpynten. Echinoderm fragments have also been reported. Falcon recorded a reptilian jaw bone with teeth in the same general locality. The sedimentological model (D.J.A. Piper in Lock et al. 1978) is of a delta complex supplied by rivers from the northeast entering a marine basin. This interpretation is based on seven lithofacies (i) Turbidites (0.01 to 1.Sm thick) with sole marks especially groove casts and Bouma C and BC sequences. (ii) Thick sandstones filling slide scars up to 30 m deep. The sliding units are mostly of turbidite facies. Channel structures and mudstone intraclasts are also observed. (iii) Shallow marine sequences occur as coarsening-upward cycles of silty shales followed by sandstones with bioturbation. The sandstones may be cross-bedded in sets up to 10m thick followed by massive sandstone (Edwards 1976b). They are sometimes capped by a coquina or oyster bed. Marine sequences are more abundant in the lower part of the formation and a shallowing marine or marine environment was suggested. (iv) Mouth bar sequences in the form of sandstones up to 3 m with largescale high angle cross-bedding. Load structures occur in the underlying thinner sandstones. These characters suggest prograding mouth bar facies. (v) Fluvial channel sequences with upward-fining sequences are cha~teristic of the upper part of the formation may be associated with (vi) Fluvial overbank facies of thick dark siltstones and mi'nor silty coals, mudstone intraclasts and plant fossils. (vii) Marginal marine facies of ironstones (some oolitic), sandy stromatolites, thin algal limestones and beds with high concentrations of bivalves,

The CSE work on the surface outcrops was published after an agreed interval (Lock e t al. 1978) in parallel with work on other islands: Wilhelmoya (Smith 1975), Hopen (Smith, Harland & Hughes 1975) and K o n g Karls Land (Smith e t al. 1976). Lock e t al. took previous work into account and made the basis for the present summary. However it could not have noticed the work of Pchelina (1977), who gave more biostratigraphic detail from molluscan faunas which was not in conflict with CSE conclusions. The Norsk Polarinstitutt map: 1:500 000, sheet 2G, Edgeoya (Winsnes 1981) accompanied by a commentary (Winsnes & Worsley 1981) follows almost exactly that in Flood e t al. (1971). The commentary remarks 'The lithostratigraphic units concern with those of Flood e t al. (1971) [see Fig. 5.11], and adopt neither the proposals of Lock e t al. (1978) for Barentsoya and Edgeoya nor those of Smith e t al. (1975) for Hopen are adopted here. It is noted, however, that a revised stratigraphic scheme for Triassic strata of the entire Svalbard will be proposed in the near future' (A. M o r k pers. comm.). This book attempts to assess and synthesize all points of view and so far as Triassic classification and nomenclature is concerned the matter is discussed in the Triassic chapter Section 18.1 and 18.3. The conclusions arrived at there are applied here without further discussion.

5.7.2

Stratal succession

Figure 5.11 shows the relation between the scheme adopted here (and justified in section 18.1.3) and earlier schemes. A generalized geological map of Barentoya and Edgeoya is shown in Fig. 5.12 showing the distribution of the principal formations. Kapp Toscana Gp De Geerdalen Fin (Buchan et al. 1965)= Negerfjellet Fm (Lock et al. 1978) >400m. This is the 'Sandstone Group' of Falcon (1928). It corresponds to the De Geerdalen Formation and perhaps the uppermost part of the Tschermakfjellet Formation of Flood et al. (1971) - units that were defined by Buchan et al. (1965) in Spitsbergen and approximately equivalent in these islands. Lock et al. (1978) based it on a measured type section at Negerfjellet in southwest Edgeoya (op. cit. p. 29) supported by five other sections extending to northwest Barentsoya.

Falcon 1928

Klubov 1965

Sandstone Group

"Sandstone formation" (Upper unit of T3)

Purple (Blue & Purple) shales group or series

"Passage Beds ! (lower formation" | two

Flood etal. 1971 Winsnes & Worsley 1981

s (.9

8 P-

units

"Argillite formation"

/ of ,A T3)

De Geerdalen Formation

v

Tschermakfjjellet Formation

Lock et aL 1978

o (.9

80~ ~2 o. Q. (~

Oil Shales group or series

T 1 and T 2

~) Sticky Keep Member

-~

(/)

(~

(Permian rocks not recognised)

"Selander suite"

~--~~) EE ~ $ eLL vo

Vardebukta Formation

Kapp Starostin

Formation

Mork et al. 1982

This work

Nege~ellet Formation

De Geerdalen Formation

De Geerdalen Formation

s (.9

Edgeoya Formation

Tschermakfjellet Formation

Tschermakfjellet Formation

~r

I

Botneheia Member

87

P3~ Oil shales I Member I ---~) ~ Barentsoya Formation

I

Blauknuten Beds ?

I I

.

.

.

Barentsoya Formation

.

.

Oil shales Member . . . .

I

I I

s

(.9

g

Barentsoya Formation o~ CO

Kapp Ziehen formation

Kapp Starostin Formation

Kapp Starostin Formation with Kapp Ziehen, Raddodalen and Veidebreen units (members?)

Fig. 5.11. Proposed nomenclature for local rock-units on Barentsoya and Edgeoya as used in this work, compared with previous authors' schemes.

.~ =~ (.9 __

88

CHAPTER 5 ironstones. But formal members were not proposed because the boundary is ill-defined (Lock et al. 1978). The lowest beds of the formation are generally characterised by abundant ironstones. But locally by grey shale. The variable thickness appears to result in part from facies variations within the unit and partly from the vagaries of the succeeding deltaic front. The formation is characterised by marine fossils- ammonites and bivalves with a bed rich in N a t h o r s t i t e s 20 to 30m above the base. This Nathorstites band forms a useful marker horizon. Silicified wood also occurs.

Sassendalen Gp Barentsoya Fm, c. 300 m (Lock et al. 1978). This formation, as defined above

Fig. 5.12. Geological map of Barentsoya (to the north) and Edgeoya, combining figs 4 and 5(B) of Lock et al. (1978). generally of a single species. Marine facies may coarsen upwards into dark siltstones or coals. These facies indicate shallow open marine, lagoonal, tidal flat swampy terrestrial environments. In addition, conspicuous rotational faults developed with sedimentation seen in the Negerpynten cliffs. The strata dip up to 20 ~ northwards as a result of the southward slipping rotation. They were noticed by De Geer (1919), Falcon (1928), CSE 1969 and described by Edwards (1976a, b). Abnormally high fluid pore pressure may have facilitated this faulting. It is not unexpected in the above complex that no satisfactory marker horizons have been identified in the formation. Tsehermakfjellet Fm (Buchan et al. 1965)= Edgeoya Fm, (Lock et al. 1978), 125m. This is the purple shale, or blue and purple shale unit of Falcon (1928) and the argillite plus Passage Beds of Klubov (1965a, b). In stratigraphic position it corresponds to the Tschermakfjellet Formation of Spitsbergen. The type section was taken at Veidemannen in southwest Edgeoya (Lock et al. 1928, p. 4). It is clearly distinguishable from the Negerfjellet sandstones above and the cliff forming bituminous shales of the Barentsoya Formation below. The type section is supported by six further measured sections, four in Edgeoya and two in Barentsoya. Thicknesses were plotted at 26 localities in the islands and range from 51 to c. 130 m. The formation is entirely missing at Mistakodden in northwest Barentsoya. The formation consists of shales with subsidiary fine siltstones becoming more abundant towards the top. There are thin red to purple-weathering clay-ironstone beds and thin argillaceous and arenaceous micritic limestones some with cone-in-cone structure. The lowest bed is of yellow-weathering calcareous silts and small nodules. The upper part of the Edgeoya Formation is, as Klubov reported, somewhat transitional to the succeeding deltaic facies and two divisions are thus discernible, the lower one being of shales and red weathering clay

and as followed by Mork et al. (1982), completely represents the Sassendalen Group in these islands, it not being practicable to map divisions within it, whereas the Group is defined by three distinct formations in Spitsbergen. It corresponds to the 'Oil Shales Group' of Falcon 1928, T I + T 2 of Klubov (1965a, b), and the Kongressfjellet and Vardebukta formations of Flood et al. (1971b) which were extended from the mainland of Spitsbergen but without detailed sections. The type section is a composite one near Kapp Ziehen in northeast Barentsoya where it rests directly on the Permian sandstones and limestones of the Tempelfjorden Group. This lower boundary at Kapp Ziehen, not well exposed, was described by Burov et al. (1965) as a pitted erosion surface. The boundaries at the two Permian inliers in Edgeoya are still less visible. The upper boundary is easily observed throughout the outcrops being marked by a sharp change from compact paper shales, often bituminous, to the overlying purple or grey shales with red-weathering concretions. The main and upper part of the formation crops out from northern Barentsoya to southern Edgeoya and was depicted in six representative measured sections (Lock et al. 1978). It is a unit of shales, often bituminous and papery towards the top and with subordinate beds of limestone, septarian nodules, calcareous siltstones and argillaceous sandstones. Septarian concretions often contain liquid bitumen, and phosphatic nodules occur lower down in the succession. At the top a distinctive bed of yellow-weathering argillaceous limestones or calcareous siltstones commonly occurs with ichthyosaur bones. This represents a widespread non-sequence and disconformity with the overlying strata. The cliff forming bituminous shales may be taken as an informal 'Oil Shale Member' in the upper part of the formation. It thins from 100m in the west to 50 m in the east. The lower part of the formation is of limited exposure near the Permian outcrops. Its relationship to the upper-part is not seen. It consists of grey shales and siltstones with a few prominent beds of yellow weathering carbonate-cemented siltstones and silty, clayey limestones. The formation is richly fossiliferous. Abundant ammonoids, often impressions, Daonella, ichthyosaur and plesiosaur bones, and fish remains are characteristic. The fauna is consistent with the euxinic interpretation of the bituminous shales forming in stagnant conditions on the sea bed. Tempelfjorden Gp. Permian strata are known from three localities: (i) at Kapp Ziehen in northeast Barentsoya reported by Burov et al. (1964); (ii) in central Edgeoya and (iii) in central south Edgeoya. Localities (ii)+ (iii) are tiny inliers (each less than 1 km 2) discovered by an Amoseas exploration party in 1963 (King 1964) and mentioned in the synthesis of Cutbill & Challinor (1965) who implied that all three exposures would correlate with the Kapp Starostin Formation of Spitsbergen. Flood et al. (1971) reported Klubov's discovery of Kapp Starostin Formation but no data were provided. Lock et al. (1978) reported on some fieldwork in 1969 at the three localities referring to all the rocks informally as Kapp Ziehen formation, but except for a general similarity with Kapp Starostin strata these occurrences could not be correlated within the two islands. The 1:500 000 geological map and text 2G (Winsnes & Worsley 1981) refers to all three localities as Kapp Starostin Formation. Therefore although correlation between Spitsbergen and these islands is not so good as with the more distant Miseryfjellet Formation of Bjornoya we adopt this nomenclature. Because of the distinct nature of the three occurrences and the convenience to label them for discussion it is proposed here to name them informally as follows: (i) The Kapp Ziehen occurrence to be the Kapp Ziehen member for that outcrop and not for (ii) and (iii) below. (ii) The central Edgeoya occurrence to be the Raddedalen member from the name of the well near that locality and which penetrated the Tempelfjorden Group.

EASTERN SVALBARD PLATFORM (iii) The Central South Edgeoya rocks to be the Veidebreen member from the neighbouring glacier. Kapp Starostin Fm (i) Kapp Ziehen member. The largest outcrop, extending for about 10kin along the northeast coast of Barentsoya described by Klubov (1965c). It is poorly exposed with only intermittent beds recorded dipping gently SSE. The outcrop suggests a thickness of at least 250 m but only the top 28 m are exposed as cherty limestones, dense, dark grey to black, in places transitional organogenic cherty rock. 60-70 m are covered. 1 m light grey shelly limestone with 10 brachiopod species. 10 m covered; 3.5m yellow organogenic cherty ferruginous rock (2 brachiopod species recorded); 10-15 m covered; 1.5 m light cherty, organogenic limestone. (7 species recorded); 10-15 m covered; 1.5 m light grey cherty, organogenic limestone (7 species recorded); 20 m covered; 1 m light grey shelly limestone (11 species recorded) 20 to 30 m covered; 5 m cherty limestone, dense dark grey with light calcite veining, echinoid spines and sponge spicules (10 species recorded); 100 m covered; 0.5 m Calcareous sandstone, green/grey, medium grained, thin-bedded, with glauconite and sponge spicules (2 species); Lower beds obsured. (ii) Raddedalen member. In central Edgeoya is a small outcrop with blocks of richly fossiliferous Permian strata but hardly exposed in situ. In the float the relationships with the overlying rocks cannot be seen. Its position is shown on the map, but it is not easy to locate on the ground. It occurs at the northern end of the pass between Storskavlen and Edgeoyjukelen. About 15 species of brachiopods, pectinid bivalves and bryozoans were collected (Lock et al. 1978). The unit is so named here because it was later the site of the well 'Raddedalen-l' drilled by the Companie Frangaise du Petrole (Total, CFP). The only previously published record was by Schwarts (1985) who, from mud samples exchanged, recorded 202m of Tempelfjorden Group above upper Gipsdalen Group etc. (see below). (iii) Veidebreen member. In Central South Edgeoya is a small outcrop in a complex exposure amongst meltstreams just north of the terminal moraine of Veidebreen. This is about 7 km NNE of the northernmost coastline of Tjuvefjorden. This exposure is of light grey chert with sponge spicules and bryozoa, but no brachiopods were collected. Fossil species were not easily identified. Palynological investigation yielded only one long ranging acritarch genus Micrhystridium.

5.7.3

Sub-surface stratigraphy

Two deep wells were drilled in Edgeoya. One in southwest Edgeoya by Norske Fina: Plurdalen-1, the second already mentioned was: Raddedalen-1 drilled by Compagnie Franqaise du Petrole (CFP). See also Section 5.9.

Raddedalen-1, 22~ 77~ The already published record (Shvarts 1985) concerns Raddedalen-1. The mud samples from this well were obtained from C F P in exchange for material from the Soviet well Grumantskaya-1. It was drilled to a depth below surface of 2823 m. The Cambridge samples were obtained through Norske Fina by exchange for Plurdalen-1 material. Below the 202m of Tempelfjorden Group, Shwarts recorded 205 m of Upper Gipsdalen Group and a Moscovian-Bashkirian boundary just below a depth of 407 m and down a further 306 m through lower Gipsdalen Group rock. Then 161 m of Culm was reported down to an unconformity at 874m. Of the remaining 1949m the upper 945m was interpreted as Early Silurian or Ordovician and the lower 1004m as Ordovician. Independently, and recently released information (courtesy Dragon Oil, was reported to Norske Fina in 1974 and 1975 on material by Cambridge Svalbard Exploration (CSE). The CSE work was primarily a palynological investigation by J. F. Laing,

89

advised by N. F. Hughes and the samples were cuttings etc. The conclusions were that below the more easily identified Permian and Pennsylvanian strata was a succession of about 2000 m of Early Carboniferous (Mississippian) and possibly late Devonian age. The Devonian palynomorphs all had ranges well into Carboniferous time if not younger. The two investigations are plotted side by side in Fig. 5.13. They were of course entirely independent, CSE results transmitted to Fina with little information other than depth in well from CFP. Obviously the C F P conclusions would be more useful. Shvarts with apparently more information on the well from C F P quoted 'foreign geologists' N. Couleau, I. Per6, A. Fedyayesky and D. Somm~ as giving the age of the lowest strata as Silurian?-Devonian. The critical evidence for Ordovician age is the conodont Drepanodus, which, if properly located in the well and properly identified and not a conglomerate clast, might well be conclusive. However, the general account of Shvarts would make this a quite remarkable result for Svalbard geology. He was able to report that the strata were a conformable sequence with dips ranging from 0 to 3 ~ and neither indicating tectonic nor magmatic activity. He suggested that Svalbard east of the Billefjorden Fault Zone was a stable platform escaping Caledonian tectonism. Apart from this conundrum the Russian report gives too much petrographic detail to recount here and generally not related to identified sample depths. The conclusions preferred here are put into context at the end of this Chapter (Section 5.9). Plurdalen-1, 21~ 77~ in southwest Edgeoya, just west of the snout Philippbreen, was drilled by Norske Fina. Cambridge Svalbard Exploration (CSE, mainly C. Croxton) reported palynologically on cuttings and selected cores which it is now possible to publish, courtesy Dragon Oil. The data here merely summarize results from six progress reports in 1973. The actual drilling occasioned widespread comment because of the conspicuous floods of red sediment emanating from the well. Because of this the first CSE study was to identify all red beds in Svalbard from the CSE collection. A summary of the results is plotted in Fig. 5.14. The whole-rock R b - S r determinations by Pringle were invited because the lithology of the red sediments appeared to be similar to the Vendian Nyborg Formation in Finnmarken from which he had obtained a result (1973). As we now know the Nyborg value (668 4-23 Ma) was significantly older than is currently thought likely (c. 600 Ma) and probably because of inherited clay minerals. On this basis the value of 410 M a (Early Devonian) could similarly be too high which could bring it to late Devonian or Early Carboniferous. Samples determined from different depths yielded no significant age differences.

5.7.4

Biostratigraphy[age estimates

?Jurassic strata. The possibility has been considered that the highest strata in the hill tops above Kvalpynten in south west Edgeoya may be earliest Jurassic, but no positive evidence has been forthcoming.

Triassic strata. Barentsoya and Edgeoya have provided rich collections of fossils (Fig. 5.15; from Lock et al. 1978, table 2). In comparison with an earlier similar plot, Flood et al. (1971b) did not emphasise the potential mid-Ladinian nonsequence separating the Barentsoya Formation from the Edgeoya Formation. No positive evidence for Rhaetian strata has been identified and the oldest strata, of which exposures are few, yielded Late (but not yet early) Griesbachian fossils. The recorded fossils, (ammonoids, stage by stage) were discussed by Lock et al. (1978, pp. 36-50).

Permian strata. Of the total of about 27 forms recorded from the Kapp Ziehen rocks by Klubov, most are brachiopods and there

90

CHAPTER 5

EDGEOYA

RADDEDALEN-1

Shvarts 1985 based on samples at 4, 8 and 10 m intervals Biostratigraphic age

W e l l d r i l l e d b y C o m p a g n i e Fran(~aise du P e t r o l e ( T O T A L ) Cambridge Svalbard Exploration (CSE) based on 56 evenly distributed samples or chippings in 4 reports from 1974-1975

Well depth (m) Lithic description

Lithic divisions based partly on recovered well log

Palynology by A.F. Dibner algae by G.P. Sosipatrova and M.F. Solov'eva Conodonts by N,N. Sobolevy 0

Late Permian 202 m

--100--

III

Palynological age, assessment by J.F. Laing advised by N.F. Hughes

Kapp Starostin Fm

Grey mottled chert with spicules

- - Sea level

b

202---200-Early Permian 205 m

-500-Middle Carboniferous 306 m

NO RESULTS

Gipshuken Fm

Approx. Wolfcampian EARLY PERMIAN

--300-- 407----400--

CSE corerlation optirnised by W.B.Harland, J.L. Cutbill and D.J. Gobbett, with unit names updated

NO RESULTS

White, light, medium and dark grey crystalline limestone II with shelly fossils, crnoids, corals, bryozoans and forams

Tyrellt]ellet Mbr Cadellt]ellet Mbr

Wordie Kammen Fm !

BASAL PERMIAN

~-6oo--

NO RESULTS

Minkinflellet Fm Ebbadalen Fm

.

.

.

.

.

Early Carboniferous 161 m

713_ ~ - - - 7 0 0 - ~

NO RESULTS

:T" : i

i: :

~800--

enlc imestones, algae, 674- ~_ 9 0 0 - / )otis, ostracods, echinoderms brachiopods, osl and foram fragments --1000Coral at 1049 m Nuia sibidca at 1054 m - 1092- ~_ 1100 - -

NAMURIAN (=EARLY BASHKIRIAN AND SERPUKHOVIAN)

(Hultberget Fm)

--1200

Early Silurian and Ordovician 945 m

Zoophytogenic limestone with scaps of algae and Giztare#a and fragments of brachiopods, crinoids, ostracods and conodonts

~ 1300-

/

-- 1400---1500--

Id White and light grey crystalline limestone with many beds of coral, pale green often pyritic fine sandstone, red fine sandstone and medium grey mediumgrained sandstone

(Mumien Fm) i

PROBABLY VISe:AN

--1600 -1649M~rophylithiclirnestone with brachiopods, crinoids andcale~rus

--1700

1819,--1800-Zoophytogenic limestone in uniform units with fine-grained limestone with numerous remains of algae in lumps and clots and fragments of brachiopods, crinoids, ostracods, and sponge spicules.

- - 1900 --2000 --2100---2200--

Ordovician 1004 m (on basis of Drepanodus)

Biogenic formations are evenly distributed as calcitic, often dolomitized cracks in limestones with black organic matter. The algae Nuia sibirica and the conodont Drepanodus was recorded

Ir Similar to Id, but mrdium grey mediumgrained sandstone is a more important constituent

H6rbyebreen Fm

--2300---2400 --2500--

Ib Similartolc butgrey sandstone of minor importance

--2600---2700--

Base of well 2823

VISE~AN OR TOURNAISIAN

--2800--

VISI~AN TO LATE DEVONIAN

la Similar to Ib but with appearance of dark grey fine sandstone as a major lithology

Fig. 5.13. Interpretations of Raddedalen-1 well (Edgeoya) by Shvarts (1985) and CSE, first published here, based on reports by J. F. Laing for Norske Fina, courtesy of Dragon Oil plc.

EASTERN SVALBARD PLATFORM

PLURDALEN-1

EDGEOYA

Well drilled by Norske Fina

Epoch

91

Stage

Zone

Well depth (m)

Equivalent Spitsbergen units ( 9 core sample)

_3

Approximate age

Norian Al~v~rrT --

-- 0 1

Barents~ya Fm (Sassendalen Gp)

Early Tdassic

Kapp Starostin Fm

Late Permian

I 3CSilicified

2 Camian 1

2 Asselian

Dolostone 538 Brucebyen Beds Wordie and . . . . . . . . 7 limestnne 555 , i Kamen i - - 602,5 - - 600 -- Cadellfjellet Mbr / Fm Oolitic and bioclastic 3A limestone - 7 0 0 . . . . . . . . . _ __Minkin_fje/letFro_ i --760.5 Quartzmc - 800 - sandston~ - 811 9

J

1

Orenburgian Gzelian

3

Moscovian

Anisian

"Early Carboniferous"

1

,~

--839-

Spathian

Slratigraphic break 9

-

Red beds almost entirely barren

-1100-

~_ I-

Z

Smithian

,~,

~

Dienedan

-1200Red beds

-1400-

_1600_ ~-1586 9 --1640- 9 1645 -1700-

Ii

i Ic. 410 al

Dark purple and red brick siltstones

8

Green beds

"1940 9 -2000spores found ~ No ? Pre-Devonian

-2200 - -2180 9

- 2300 -2344 9 "~Ann

Fig. 5.14. Interpretation of Plurdalen-1 well (Edgeoya), by CSE, first published here, based on reports for Norske Fina by C. A. Croxton, I. Pringle, J. L. Cutbill, D. J. Gobbett & A. B. Reynolds, courtesy of Dragon Oil plc. seems little chance that the faunas recorded would enable independently dating the seven fossiliferous beds so the fauna must be taken as a whole. A CSE collection of bivalves brachiopods and bryozoans from the Radeddalen outcrop was identified by D. J. Gobbett (who had monographed Svalbard Carboniferous and Permian brachiopods, 1963) and 15 brachiopod forms were listed (Lock et al. 1978, p. 18). Of these only four are named in common and another four might be the same with different names. A Ufimian age was in the end favoured (Lock et al., p. 16).

5.7.5

Madeami

wO .1-.LL

,,] I--

Possible

sequence I I[

Daonella trami, Panapopanoceras vemeuili, Ptychites trechlaeformis

Subaspedum Chischa

Gymnotoceras ?laqueatum

Deleeni Varium

? Hollandites Koptoceras

Caurus

Keyserlingffes subrobustus, Posidonia aranea, Svalbardiceras cf. spitzbergense

Subrebustus

"Pseudomonotis" occidentalis, Xenoceltites Arctopdonites nodosus

Tardus Romundefi Sverdrupi

Euflemingites, Posidonia mimer "Pseudomonotis" cf. multiforrnis

Candidus Strioatus Commune Boreale Concavum

Ophiceras (?) sp Claraia stachei

NOnL I I ?

Bivalves, bryozoans and brachiopods: more KAPPTOSCANA than 40 forms recorded by Klubov (1965) and rKappZiehenMbr) 17 brachiopods by Lock et al. (1978)

Fig. 5.15. Edgeoya and Barentsoya Triassic biostratigxaphy, after Flood, Nagy & Winsnes (1991) and Lock et al. (1978).

-1900 -

-2100 -

Guadelupian Kungurian

Rb-Sr 9 age of red beds

- 1 8 0 0 - ~1810 9

7

Halobia zitteli Nathorsites mcconnefli, N. tenuis, N. gibbous, Precladiscites cf. martini

Lopingian

LATE =ERMIAN

-1500-

Green siltstone and red brick argillite

Griesbachian

Unit 5 ? Bashkidan to Late Silurian spores

-1300-

,,'dz ,,?o

Nanseni

Pilaticus

r -1000

~L~

_i

Sirenites sp., Nathorsites gibbous

Meginae Poseidon

Ladinian

3B

- 900 - -

Macrolobatus Welled

Obesum

Tyrellt]ellet Mbr

m~ w~ O0

Dawsoni Kerri

Su~eflandi

- 400 -484.5 - _ 500 --

Meleagdnella antiqua, Lingula cK polads, Pentacrinus (?) sp., Estheria cf. minuta

Dilleri

Eady Permian

Gipshuken Fm 3 Carbonate section --

Palynomorphs and Pterophyllum sp., Macrotaeniopteris sp., Taeniopteris sp., Podozamites sp., Tod/tes sp.,

Magnus 1

- 300 --

Suess Columbianus Rutheffo~i

2

"Shaly Lower Triassic." --100 ---128.5- 2 0 0 --

Formations

Marshi

Rhaetian Descriptive units

Key Fossils (after Flood et al. 1971 & Lock et al. 1978)

Structure and igneous bodies

The large area of the two islands, a distance of > 150 km N-S and 75 km E - W is occupied almost entirely by Triassic outcrops representing a maximum thickness of between 800 and 900 m with a

typical relief of between 400 and 450 m. The strata thus seem to be flat lying. However interest is attached to the detailed structure from the point of view of hydrocarbon exploration. Figure 5.16 shows contours at the top of the Barentsoya Formation from data obtained in 1969 (Lock et al. 1978). There is insufficient control to have confidence in the exact structure but it is clear that there are significant minor basins and swells with a closure of 50-100m and two of the Edgeoya swells were drilled. Sills in the main islands and the basic bodies that constitute the 'thousand islands' (Tusenoyane) were described in considerable petrographic detail by Backlund (1907 et seq.). The distribution of the typical sills in Svalbard was summarized by Tyrrell & Sandford (1933). It is noteworthy that in the two main islands and especially in their western coastal areas. This seems to be part of a zone running the length of Storfjorden and Hinlopenstretet. Their age (?latest Jurassic through to Barremian) is discussed in Chapter 19. They affect the structure locally as might be expected.

5.8

Hopen

Hopen (70~ I'N, 25~ is a straight narrow island trending between N N E - S S W and NE-SW, about 35 km long and 0.5-2.5 km wide, with a mountain plateau around 300m rising to 370 m at Iversenfjellet in the south. The plateau slopes gently to the SE and is bounded by cliffs that fall directly into the sea or to a low raised beach. Shallow waters (largely uncharted shoals) offshore for more than 1 km prevent access by all but small boats and then only at a few favourable landings. At one of these is the radio station on the east coast about 8 km north of Kapp Thor at the southern tip of the island below Iversenfjellet. The plateau is punctuated by about five saddles each corresponding to the narrow necks in the islands plan. These are probably the remains of valleys in a much larger island.

92

CHAPTER 5

Fig. 5.16. Generalized structural map of Barentsoya (to the north) and Edgeoya, with structure contours in metres for the top of the Barentsoya Formation, combining figs 4 and 5(B) of Lock et al. (1978).

The regular elongate shape of the island implies a N E - S W structural control confirmed by lines of offshore submerged rocks; but there is no apparent dip across the island - the sloping plateaux being the result of differential erosion between east and west coasts of the island with stronger seas and currents on the west. Transverse structures cut across the island. Some are anticlinal and correspond with the saddles, some are the result of faulting which let down higher strata in the north; but the dips in the step-faulted blocks are southwesterly. They strike W N W - E S E . The net effect is to displace the marker horizon at the top of the lower formation from 325 m asl in the southwest systematically to 150-160 m at Lyngefjellet and up to 180 m at the northeast tip.

5.8.1

Earlier work

This account is as summarized by Smith, Harland & Hughes (1975) who reviewed earlier researches and gave the most complete account of Hopen geology to date based on 1969 and later fieldwork (Fig. 5.17). The history of geological exploration is brief because of the remoteness and difficulty of landing on the island protected by inshore shallows. Access for drilling in 1972 and 1973 was by means of hovercraft from a ship anchored some distance off-shore. The rocks were taken to be Mesozoic because the dominant sandstone lithology favoured correlation with the Spitsbergen

Fig. 5.17. Geological map of Hopen and a longitudinal section along the island, redrawn with permission of Cambridge University Press from figs 2 and 3 in Smith et al. (1975).

EASTERN SVALBARD PLATFORM succession, but opinion as to their age wavered between Triassic and Cretaceous from the lack of decisive diagnostic fossils afforded by the cursory visits. Nathorst's (1884) study of Paleozoic Arctic floras maps Hopen as Triassic but his 1910 m o n o g r a p h leaves it blank. He failed to land on Hopen in 1889. He later suggested a Jurassic age on the basis of plant fossils collected by the Prince of Monaco's expedition in 1898. Hoeg (1926), from the presence of coal, argued a Cretaceous age. Norwegian expeditions in 1924 & 1926 (Iversen 1926) resulted in some geological observations as well as a topographic map, e.g. Werenski61d (1926) on general geology, Hoel (1925) on fossil plants and Bodylewski (1926). F r o m these Hoeg proposed a late Triassic and the others an early Cretaceous age. Another Norwegian expedition to Franz Josef Land (Horn 1932) collected pieces of coal in passing and a Cretaceous age was suggested. These data were perhaps the only basis for later published estimates, e.g. Frebold (1935, 1951) and Orvin 1940 assumed Cretaceous ages in their review syntheses of the Barents shelf and Spitsbergen respectively. However, Selling (1944, 1945 and 1951) from three studies of Hopen concluded only Late Triassic to Early Cretaceous possible ages. Buchan et al. (1965), with no further evidence, suggested a Triassic correlation, and a Swedish-Finnish expedition in 1965 from observation at sea also suggested a Triassic age. These questions were settled from field work in 1969. Flood, Nagy & Winsnes (1971) who found not only that the lithologies matched those of the De Geerdalen Formation of Barentsoya and Edgeoya, but confirmed this correlation by collecting Pteridophyllum common to both. They also reported Halobia zitteli, a gryphaea, and one ammonoid, probably Arctosirenites. These ruled out a Cretaceous age but were not so specific as to a likely Late Triassic age. However the published report is brief with no section. Russian work in 1966 and 1971 (Pchelina 1972) resulted in a composite stratigraphic succession for the southern part of the island divided into Carnian and Norian stages partly on lithological grounds but with reference to fossil plants, bivalves and phyllopods. She suggested that the north of the island might preserve Jurassic strata. Similarly Worsley (1973) suggested that his proposed Wilhelmoya Formation might occupy the hill tops in the north where there was some evidence of down faulting. Exploratory wells were drilled by Norske Fina and associates in 1971 and 1973. These followed a preliminary study of samples by W B H in 1967 and field work in 1969 by a CSE party. The resulting paper (Smith, Harland & Hughes 1975) summarized available knowledge and reported permissible results from these investigations.Their conclusions are summarized below.

weathering bright red-brown to purplish which tend to follow the coarser horizons. At the bottom is a horizon of brown bioturbated siltstone. Rare ammonoids and abundant bivalves are found in the clay ironstone beds. The member is marine throughout with ammonoids, bivalves, ichthyosaurs, acritarchs and dinoflagellates. The scarcity of ammonoids and the good spore and pollen content suggest a near shore environment. Worsley suggested an Early Jurassic age but the palynological evidence makes a Rhaetian age more likely. Iversenfjeilet (= De Geerdalen) Formation, 325 m down to sea level at type section. This unit forms the greater part, and always the lower part, of Hopen. It consists of alternating sandstones, siltstones and shales in cyclothems of metres or decimetres. Shales or siltstones grade upwards into fine-, medium- or coarse-grained sandstones. The uppermost part is of calcareous, yellow-weathering sandstones with bivalves. The prominent ledge at the top may be Worsley's Basal Member. Lower down, siltstone and shale are the dominant lithologies, nodular ironstones, weathering red-brown are common at the base of the shale beds. Associated shales may be green or red. Siltstones are often bioturbated. The lower 100 150m in the south are often coarse-grained with large channel structures tens of metres across with cross bedding. The sandstones are often calcareous with beds of dolomitic mudstone. The age of the Iversenfjellet unit is probably latest Carnian to Norian and possibly earliest Rhaetian. Stratigraphic section at northeast Lyngefjellet from 290 m down to sea level from Smith et al. (1975).

Wilheimoya Fm Lyngefjellet (sandstone) mbr, 80+ m top of exposure; 15 m medium-bedded white sandstone with dark silty shale interbeds 35m massive quartz sandstones weathering white, thin bedded in part, occasionally pebbly; cross-bedded and ripple marked. 29 m Interbedded fine to medium sandstone and grey siltstone

Flatsalen (shale) mbr, 55 m; 55 m grey silty shales with red-weathering nodular ironstones especially near base. Three prominent beds of interbedded fine sandstone and siltstone. Bioturbated brown-weathering siltstone at base; 1 m prominent bed of yellow-weathering calc siltstone to fine sandstone with thin layers of coarse sand near top.

Iversenfjellet Fm 155 m; 95 m alternating fine to medium sandstone, silty shale and clay ironstone. about 13 cycles in this interval. Sandstones have ripple marks and small scale cross-bedding. Sandstone and siltstone often finely interlaminated. Shaly beds generally thicker (3-4 m) than sandstones (2 m); 60 m alternating sandstones and siltstones; sandstones medium-grained, thin to thick bedded, relatively little shale or siltstone.

5.8.3 5.8.2

Succession from outcrop

F r o m sections measured and collected from north to south three stratigraphic formations were proposed. However, Worsley (1973) proposed the Wilhelmoya Formation which has priority and to which he related the two upper units on lithological grounds. Smith et al. (1975) units are therefore taken as members of the Wilhelmoya Formation.

Wilhelmoya Formation Lyngefjellet (sandstone) Member, 80 m to top of hill is limited to Lyngefjellet and north in the hill tops. It is a white-weathering medium to coarse-grained sandstone mostly of quartz with occasional pebbles, cross bedding and ripple structures in the middle. Carbonized plant fragments are abundant and are often current oriented. The facies suggest fluvial deposition. The age of the member was estimated biostratigraphically as latest Triassic to earliest Jurassic (Rhaetian to Hettangian). It correlates with the Transitional and Tumlingodden Members of the type section of the Wilhelmoya Formation (Worsley 1973). Flatsalen (shale) Member, 55 m. The appearance is similar to the 'Aucella Shales' of the Janusfjellet Formation of Spitsbergen. It crops out as a less resistant unit between the sandstones above and below. Its main outcrop is in the north but three other outcrops cap the hills including Iversenfjellet. The dominant lithology is dark grey silty shale with prominent siltstone and fine sandstone horizons. The shales have beds of nodular clay-ironstone

93

Subsurface succession

The two wells, Hopen-1 and Hopen-2, drilled by Norsk Fina 19711973, were investigated by Cambridge Svalbard Exploration and summarized in Fig. 5.18. Hopen-1, 25~ 76~ near the southern tip of the island was drilled at near sea level to a depth of 908m and penetrated Norian into Anisian strata as estimated palynologically by M. G. Mortimer. Hopen-2, 25~ 76~ was sited on a hill top at the north of the island higher in the succession. J.F. Laing reported on the Triassic palynology. The Kapp Starostin Formation was met at about 1360m and drilling continued to c. 2870 still probably in lower Gipsdalen Group strata. There was little difficulty in correlating the strata with the Spitsbergen succession. Correlation between the two wells and those on Edgeoya as discussed in the Section 5.9.

5.9

Correlation of four exploratory wells: Edgeoya and Hopen

The four exploratory wells noted above (Sections 5.7.3 & 5.8.3) were drilled in the early 1970s namely: Plurdalen-1 and Raddedalen-1 in Edgeoya and Hopen-1 and Hopen-2. Cores and cuttings were made

94

CHAPTER 5

available to Cambridge Svalbard Exploration by Norsk Fina for independent opinions on the ages of the samples. The materials are now part of the Svalbard collection of the University of Cambridge by courtesy of Dragon Oil plc. The 25 biostratigraphic progress reports remained confidential until recently. In due course it would

be sensible to publish the mainly palynological results, and better still to combine all investigations in a comprehensive assessment. Only the broad conclusions of the Cambridge investigations directed by W.B.H. are reported here. The only other known publication was by Shvarts (1985) on Raddedalen-1 drilled by CFP. Some of this

EASTERN SVALBARD PLATFORM

95 Correlation with surface geology of Hopen

HOPEN-2 Approximate correlation with

-

BiUefjorden Trough RADDEDALEN-1

Early Triassic

Tatadan, Kazanian& Kungurian Artinskian Sakmadan& Asselian Kasimovian& Gzelian

- Mcmr Bashkilian

Namurian

•LUO

..........

....

Kapp Starostin Fm Gipshuken Fm

~Q(.

:111:

Svenbreen Fm

2

?__~,~

Lynge~ellet Sandstone Fm Flatsalen Shale Fm

1

i

I

$4.=a

HOPEN-1

: - - ~ ?9- ~ .~. . . . . . . . . . . . . . . I~' 3C

~

3b

, ~

3a

~

Iversenfjellet Fm

i a. o

Rhaetian

'< Norian and Camian

o VI-~ I I /

H

.....

II

.--9--

Cadelff]elletMbr Min~t Mbr~ Ebbadalen Fm

PLURDALEN-1 --lz

?--

Ladinian

t .9"

I

Anisian an( Scythian

Id

IV

Late Permian

Ill

Ic

Ib la

Fig. 5.19. Suggested correlation of the Edgeoya wells (Raddedalen-1 and Plurdalen-1) and Hopen-1 and Hopen-2 wells, based on CSE reports to Norske Fina and especially the final report by J. F. Laing, courtesy of Dragon Oil plc. material was exchanged by Norsk Fina and was added to the Cambridge investigation. The material Shvarts investigated was obtained by exchange for a Russian well, Grumantskaya-1. The preliminary conclusions are reported above: two Edgeoya wells in Section 5.7.3 and two Hopen wells in Section 5.8.2. An attempted correlation is shown in Fig. 5.19. The major problem was the age of the relatively barren red beds low in the Edgeoya wells. It was unexpected that the two Edgeoya wells should appear to be so different; still more unexpected that the two

reports on Raddedalen-1 should differ so much. There is probably a significant geological difference between the two Edgeoya wells suggesting separation by a minor fault. Both Edgeoya successions, according to the CSE interpretation, fit the idea of Svalbardian tectonics, possibly strike slip faulting accompanied by transtension with local subsidence in the typical Billefjorden continental environment. Triassic and possibly late Paleozoic strata appear to thicken systematically towards the southeast.

Chapter 6 Northern Nordaustlandet (and associated Islands Storoya, Kvitoya) W. B R I A N

HARLAND

6.1 6.2 6.2.1 6.2.2 6.2.3 6.2.4 6.3 6.3.1 6.3.2 6.3.3

Early work, 96 Stratal succession, 96

6.4.1 Laponiahalvoya granites, 105 6.4.2 The Rijpfjorden, Rijpdalen and Duvefjorden granites, 106

Hinlopenstretet Supergroup, 99 Murchison Bay Supergroup, 100 Kapp Hansteen Group, 103 Brennevinsfjorden Group, 103

6.5

Subjacent metamorphic complex, 104

6.6 6.7

6.4

Late tectonic plutons, 105

Evolution of ideas, 104 Migmatic and magmatic components, 104 Supracrustal inclusions, 105

Nordaustlandet is the second largest island in the Svalbard archipelago. It has been generally inaccessible by ship because of polar pack ice except for the west coast, or in exceptional summers. Exploration has therefore been limited. The major part of the interior is covered by two large ice caps: Vestfonna and (the large) Austfonna which forms all of the southern coastline in the eastern part of the island. Pre-Devonian, mostly Precambrian outcrops of solid rock extend along the northern and northwestern seaboard. Wahlenbergfjorden divides the west coast with post-Devonian rocks cropping out to the south of it. These have already been referred to in Chapter 5 so that the main object in this chapter is to outline what is known of the older rocks. Because of the ice caps covering the major part of the island, exposures, especially in the north and east, are often isolated on promontories along the highly indented coastline (Fig. 6.1).

6.1

Early work

After the early visit by Parry in 1828 research was largely by Swedish geologists with A.E. Nordenski61d's sledge journeys in 1861, 1866, 1869 and 1873. A Swedish initiative led to the Russo-Swedish Arc of Meridian Survey along both sides of Hinlopenstretet. During the period 1899 to 1902 (De Geer 1923; Nathorst 1910) and later the SwedishNorwegian expedition based at Sveanor in Murchisonfjorden (Kulling 1932) resulted in a thorough study of the Hecla Hock rocks (Kulling 1934). Alongside this were a series ofmultidisciplinary expeditions from Oxford University in 1924, 1935-36 and 1951. Sandford accompanied the 1924 expedition (1926) and since then he interpreted the many careful observations made by non-geologists aided latterly by the use of oblique air-photographs (1950, 1954, 1956, 1963). From their extensive surveys these expeditions for long provided the most reliable maps of Nordaustlandet (e.g. Glen 1937). The above work had depended on ship and sledge; then after sundry visits in 1965 the Norsk Polarinstitutt surveyed the large area of older rocks with helicopter transport. The resulting accounts are the principal sources for this chapter (Flood et al. 1969; Hjelle 1966, 1978a, b; Hjelle, Ohta & Winsnes 1978; Ohta 1978, 1982a, 1985). However, later isotopic studies have further elucidated the tectonostratigraphic history (e.g. Gee et al. 1995) and consolidated the evidence for a major unconformity to divide and so practically eliminate the Botniahalvoya Supergroup. Isotopic ages for all Svalbard included earlier data for Nordaustlandet (e.g. Hamilton & Sandford 1964; Gayer et al. 1966; Edwards 1976; Edwards & Taylor 1976).

Minor igneous bodies, 106

6.5.1 Acid intrusions, 106 6.5.2 Basic layers to northeast, 106 6.5.3 Dolerite sills and dykes, 106 Summary of isotopic ages, 106 Structure of Nordaustlandet, 107

6.7.1 A Barents craton, 108 6.8

The Lomonosov Ridge in relation to Nordaustlandet, 108

Quaternary studies were undertaken but are discussed in Chapter 21 (e.g. Salvigsen 1978). Various geological maps and accompanying descriptions consolidated the information as follows: 1:500 000.3G (Hjelle & Lauritzen 1982) and 4G (Lauritzen & Ohta 1984, and I:IM Bedrock Map (Winsnes 1988). Russian work was included by Krasil'shchikov (1967) and in his Precambrian synthesis (1973). Sundry visits in western Nordaustlandet added miscellaneous observations by Cambridge parties (Knoll 1982a, 1984; Hambrey 1982; Hambrey, Harland & Waddams 1981; Harland, Hambrey & Waddams 1993).

6.2

Stratal succession

Confining the study area in this chapter to the land north of about 79~ t, with few exceptions all the exposures to the north are of preCarboniferous and all to the south are of post-Devonian rocks. The exceptions include dolerite intrusions of probable Cretaceous age and one outcrop of Carboniferous/Permian strata at Idunfjellet, north of Wahlenbergfjorden. It has been convenient to include consideration of these exceptions in (the preceding) Chapter 5. The sequence of strata as worked out by Kulling (1932/4) and by Norsk Polarinstitutt geologists (e.g. Flood et al. 1969; & Ohta 1982), modified by Gee et al. (1995) is compiled in Fig. 6.2. The origin of the names in the evolving scheme is discussed here and adopted for descriptive purposes. (1) On the names. From Kulling's classic work the names Kap Sparre, Murchison Bay, and Kap Hansteen were introduced in 1932 in the first Swedish report using Swedish place name spellings. His full report with definitions was in English (1934) with Cape Sparre, Murchison Bay and Cape Hansteen. The original Swedish names have been generally followed but often mistakenly edited into the Norwegian spelling of Kapp for Kap, whereas the Norwegian place name is Sparreneset. In this work Sparreneset formation is introduced for what is only a part of the original Kap (Cape) Sparre Formation to avoid ambiguity which, unfortunately, was not done by Harland, Hambrey & Waddams (1993). Similarly the revision e.g. by Lauritzen & Ohta (1984) limits radically the meaning of the original Kap Hansteen Formation to a part of it, namely their Kapp Hansteen Formation. The new spelling is intended for the units as they have been revised; but the English form is used in discussion when referring to Kulling's units as he described them. Krasil'shchikov (1967) described the tillite-like rocks of Nordaustlandet with a radical redivision of Kulling's scheme. This was accepted by Harland (1985) and Harland et al. (1993) but with mistaken application of two names that are corrected here. However the major Norsk Polarinstitutt geological exploration of Nordaustlandet carried out in 1965 when published did not take account of Krasil'shchikov's work (Flood et al. 1969). The following notes attempt to clarify a confusing nomenclature in a rapidly developing geological understanding as shown in Fig. 6.2.

N O R T H E R N NORDAUSTLANDET

97

Fig. 6.1. Map of northern Nordaustlandet showing principal topographic features, ice-rock boundaries and major place names. (1) Adlersparrefjoren; (2) Bodleybukta; (3) Botnvika; (4) Bragerbreen; (5) Bragneset; (6) Depotodden; (7) Ekstremhuken; (8) Gimterbreen; (9) Gylde~n6yane; (10) Holmboeodden; (11) ldunneset; (12) Isrundingen; (13) Kapp Fanshawe; (14) Kapp Lady; (15) Kapp Laura; (16) Kapp Lindhagen; (17) Kapp Lord; (18) Krossoya; (19) Langgrunodden; (20) Lindhagenbukta; (21) Maudbreen; (22) Nilsenbreen; (23) Nordporten; (24) Nordre Franklinbreen; (25) Normanbreen; (26) Oxfordhalvoya; (27) Pentavika; (28) Rijpbreen; (29) Ringertz6ya; (30) Schweigardbreen; (31) Selanderneset; (32) Sore Franklinbreen; (33) Svartneset, (34) Zeipelodden.

(i) Kulling's (1932, p. 142) preliminary scheme:

His full scheme with descriptions in 1934:

'Kap Sparre-formationen Sveanor-formationen Murchison bay-formationen Kap Hansteen-formationen Prim~irt liggende Ok/int.' (Primary layers unknown)

Cape Sparre Fm Sveanor Fm Murchison Bay Fm Cape Hansteen Fm

(ii) Hinlopenstretet Supergroup as defined just across the strait in Ny Friesland (see Chapter 7), for the Oslobreen and Polarisbreen groups (Harland, Wallis & Gayer 1966). The upper carbonate part of Kulling's (original Cape Sparre Formation has proved to be the equivalent of the Oslobreen Group with an Early Cambrian Krossoya unit and an Early Ordovician Sparreneset unit (informally introduced here). Krasil'shchikov's (1967) revision distinguished his Gotiahalv~ya Group (equivalent to the Polarisbreen Group) by making three formations that are equivalent to the three formations in the Polarisbreen Group as follows. The Klackbergbukta Formation (the equivalent of the Dracoisen Formation in Ny Friesland comprises the upper pelitic part of Kulling's Cape Sparre Formation. The Sveanor Formation follows Kulling and corresponds to the Wilsonbreen Formation in Ny Friesland The Backaberget Formation of Krasil'shchikov (equivalent to Ny Friesland's Elbobreen Formation) is the lower pelitic part of Kulling's Ryss6 Formation. ('fii) Kulling's (1932) Murchison Bay, rather than Murchisonfjorden of Flood et al. (1969), is retained as the name for this supergroup on the basis that whereas he did not distinguish the Franklinsundet Group formations

(thinking they repeated younger rocks in the opposing limb of an isoclinal fold, he nevertheless did include these rocks in his Murchison Bay unit, a name that has been widely used. (iv) The Cape Hansteen Formation of Kulling was widely used as the name for the rocks older than the Murchison Bay succession. Flood et al. (1969) in effect divided Kulling's Cape Hansteen Formation into two: the Kapp Hansteen Formation with a conspicuous acid volcanic component and the Brennevinsfjorden Formation largely of shales and sandstones. They noted a conglomerate between but were not certain which of the formations was the younger, opting tentatively (but as it proved mistakenly) for the Brennevinsfjorden Formation as the younger. They combined the two formations into the Botniahalvoya Group which was indeed Kulling's Cape Hansteen Unit. However, Ohta (1982) demonstrated that the Kapp Hansteen volcanic sequence rested with angular unconformity above the Brennevinsfjorden siliciclasts. This evidence was presented in more detail by Gee, Johanssen, Ohta et al. (1995) which scheme is followed here. The conclusion is that a significant folding episode divided the Botniahalvoya Group which therefore ceased to be a useful unit and Gee et al. instead transferred the name Botniahalvoya to the unconformity, and so presumably to the diastrophism. (v) Meyerbnkta and Austfonna rocks. There is some difficulty over the correlation of the extensive outcrops around Rijpfjorden and to the east. These were mapped by Flood et al. (1969) as the Austfonna Formation in the south and the Kapp Platen Formation in the north and were included at the top of their Botniahalvoya Group. However, Ohta (1982) in extending downwards the Murchison Bay Supergroup included within the outcrops on L~tgoya his new Meyerbukta Formation at the base. He then appeared to define it as a group by including the three formations of the Austfonna Group which he tabulated (p. 44) within his Murchisonfjorden Supergroup. Lauritzen & Ohta (1984) also

NORDAUSTLANDET Formation

Group

NY FRIESLAND Supergroup

Group

Sparreneset 100 (10-17) Kross~ya (10-17) Klackbergbukta 650 (6) Sveanor* 300 (2) Backaberget 290 (6)

Formation Valhallfonna (8)

Oslobreen 1200 (3)

Kirtonryggen (5) Ditlovtoppen (5)

Hinlopenstretet (11) (5) Gotiahalv~ya (6)

Polarisbreen 9OO (3)

Dracoisen (5) Wilsonbreen (5) Elbobreen (5)

Roaldtoppen (7)

Akademiker -breen 1350-2400 (3)

Backlundtoppen (3) Draken (3) Svanbergfjellet (5) Grusdievbreen (5)

Ryss~* 750 (1-2) Hunnberg* 500 (2)

Oxfordbreen (3)

Raudstup-S~ilodd* 550 (2) Norvik* 340 (2)

Celsiusberget (7)

Flora* 1250 (2)

Murchison Bay* (2)

I.o v t--

o ~0

~, E

Kapp Lord 1000 (7)

Glasgowbreen (5) Veteranen 3800 (3)

0 ..1

Westmanbukta 625 (7)

Kingbreen (5) Franklinsundet (7)

Persberget >150 (7) Meyerbukta (9)//~C~.ntr~" in i^1 / ...... "" J(Innvikhogda) ? j/ 400 m

Basal quartzite (9) -(-Ausffonna in C---

_ 9

Kontaktberget g. (13.) / ~ 1 6 ] Laponiahalv~ya ~ (13) 9 -Rijpdalen Laponiat]ellet g. (13)~ra~it-~s granites (13-16) ~ (16) Quartz porphyry, porphyrite, acid andesite and ~ tholeiite volcanics / / / i n Kapp and intrusive f m s j centre Hansteen inW ~ v " ..ane 2000(7) a J Botnia(16) ~-~-f~.~-~-~ ~/ halv~ya Upper sst. and sh. (9) in W , ~unconf. (13) Middle qtz. and sh. (9) ~ Lower sh. and sst. (9) ~ in centre BrennevinsBasal quartzite// fjorden >3000 (7) ( 9 ) ./ Helvetsflya _ ~ _ (16) _ Migmatites with gneisses and granites of Proterozoic age intrusive into above two groups 1950_10501 (16) Paragneiss and paleosomes in Duvefjorden Complex (12) (=metamorphic complex of Sandford 1956)

Kortbreen (5)

__

Vildadalen (5) Planetfjella 4750 (3) Fl~en(5) "-p ,-, ~ O "~ .o'= ~

i

,

9

r ,- .

Harkerbreen 4150 (3)

.

. ~ ~

.

i

,

(19) (14) Atomfjella Complex (4)

Finnlandveggen 2700 (3) ?,~Jv~,_, ?

~

(18)

Granitoids

~

(15)

Fig. 6.2. Preferred names for rock units in Nordaustlandet and their approximate equivalents in Ny Friesland, with estimated thicknesses in metres, mainly based on Harland (1997, table 2) with permission of Norsk Polarinstitutte. The origin of the names is indicated by the numbers in brackets: (1-2) Nordenski6ld in Kulling (1934); (3) Harland & Wilson (1956); (4) Abakumov (1965); (5) Harland et al. (1966); (6) Krasil'shchikov (1967); (7) Flood et al. (1969); (8) Fortey & Bruton (1973); (9) Ohta (1982); (10) Lauritzen & Yochelson (1982); (11) Lauritzen & Ohta (1984); (12) Gramberg, Krasil'shchikov & Semevskiy (1990); (13) Gee et al. (1995); (14) Johansson, Gee & Larionov (1995); (15) Larionov et al. (1995); (16) Gee & Teben'kov (1996); (17) this work. The Kapp Hansteen Group is defined by two formations in Botniahalvoya: Norgekollen (quartz porphyry) Formation, above and Gerarodden (volcaniclastics) Formation below, and in the Rijpdalen area it would include the Svartrabbane Formation as plotted. *, detrital zircons indicate maximum age of Strata: (18) Gee & Hellman (1996); (19) Hellman et al. (1997).

NORTHERN NORDAUSTLANDET showed the Meyerbukta Group as equivalent to the Austfonna Group in the east. However, already Flood et al. (1969) had shown that the Austfonna Formation was not only intruded by quartz porphyry but also cut by the Rijpfjorden granite. Moreover they had shown it to be continuous with the Brennevinsfjorden Formation, which was, however, then thought to lie above the Kapp Hansteen Formation. The outcome must be that the Austfjorden and Kapp Platen formations are older than the Kapp Hansteen Group and correlate with and belong to the Brennevinsfjorden Group whereas the Meyerbukta Unit is clearly the lowest unit so far recorded within the Murchison Bay Supergroup. It cannot thus be defined by the Innvikhogda, Djevlaflora and quartzite formations of the Austfjorden Group but rather as its own formation which is included here within the Franklinsundet Group as the rocks were originally so included by Flood et al. (1969). This has been clarified by Gee et al. (1995), Larionov et al. (1995) and Gee & Teben'kov as Fig. 6.2. (vi) The Granites. The granites were originally thought to be ancient but the relatively unfoliated and pink rather than grey granites generally appear to have intrusive contacts and would therefore be younger than the adjacent rocks. By analogy with the granites in northwest Spitsbergen which Holtedahl argued were 'Caledonian', it was thought by Kulling, and by most geologists until recently that the late tectonic granites would also be Paleozoic. Indeed isotopic investigations supported this view as shown in the compilations of Gayer et al. (1966) and Ohta (1992). Values consistently averaged around 400 Ma mostly by K - A r and Rb-Sr determinations mainly on biotite, muscovite and whole rock. However, the application of uranium-lead isotopic studies of zircons opened a new window on the problem. Many apparently younger granites are now yielding ancient zircons. Therefore if the zircons represent the age of original cooling of the granites it appears that many Precambrian granites have been subject to later, Paleozoic reheating. Making the assumption that the zircons were not inherited from an older basement we now have the prospect of a radical reinterpretation of the Nordaustlandet granites as Proterozoic (Gee et al. 1995; Larionov et al. 1995; Gee & Teben'kov 1996). (vii) The migmatites. Increasingly eastwards migmatites prevail. They invade older strata of which fragments of a ghost stratigraphy may be interpreted. They are clearly older than, through probably related to, Prins Oscars Land granites and probably the Laponiahalvoya granites. They would thus appear not to be Caledonian migmatites although modified in Paleozoic time, but rather developed from migmatites associated with the Kapp Hansteen magmatic events. (viii) Duvefjorden Complex. This name introduced by Teben'kov (Gramberg, Krasil'shchikov & Semevskiy 1990) usefully signifies the metamorphics, migmatites and granites east of Rijpfjorden, whose age is not established. It probably represents the Precambrian Barents Craton.

6.2.1

Hinlopenstretet Supergroup

This s u p e r g r o u p is set o u t here as c o m p r i s i n g t w o groups.

Oslobreen Group Sparreneset formation (informal) Krossoya formation (informal)

Gotiahalvoya Group Klackbergbukta Formation Sveanor Formation Backaberget Formation T h e H i n l o p e n s t r e t e t S u p e r g r o u p was defined in N y F r i e s l a n d to the west o f H i n l o p e n s t r e t e t ( H a r l a n d , Wallis & G a y e r 1966) c o m p r i s i n g the O s l o b r e e n G r o u p ( C a m b r o - O r d o v i c i a n f o r m a t i o n s ) a n d the P o l a r i s b r e e n G r o u p ( V e n d i a n f o r m a t i o n s i n c l u d i n g tillite horizons). Similarly o u t c r o p s in N o r d a u s t l a n d e t o n the east side o f H i n l o p e n s t r e t e t were described earlier by K u l l i n g as the C a p e Sparre F o r m a t i o n a n d the S v e a n o r F o r m a t i o n respectively. T h e C a p e Sparre F o r m a t i o n (850 m) was divided by K u l l i n g (1934) i n t o six series ( m e m b e r s ) thus: (6) (5) (4) (3) (2) (1)

Upper Upper Upper Lower Lower Lower resting

D o l o m i t e , 140-200 m Quartzite, 110 m Shale 1 3 0 - 1 4 0 m Dolomite 120m Quartzite 30-40 m Shale 250 m. o n the S v e a n o r (tillite) F o r m a t i o n .

99

Winsnes (Flood et al. 1969) redescribed and measured further sections of this unit which he renamed the Kapp Sparre Formation in the same arrangement, but increasing the thickness estimate to 1200 m. This scheme was followed by Lauritzen & Ohta (1984). A more detailed section of the Sveanor Formation was recorded by Edwards (1976). Krasil'shchikov (1967, 1973) had also recorded sections and redivided the succession so that Kapp Sparre Formation was limited to Kulling's division (6) above and the remainder was named Klackbergbukta Formation. This reclassification was followed by Harland (1985) and again by Harland, Hambrey & Waddams (1993), but mistakenly mistranslating the name Klackberget. Krasil'shchikov's Blackaberget Formation (which constitutes the upper pelitic part of Kulling's Rysso dolomite Formation) was also accepted by Harland et al. These revisions have the advantage of distinguishing an upper Early Paleozoic carbonate unit, a Vendian siliciclastic unit and a (mainly) preVendian carbonate unit. The upper two units correlate well with the Oslobreen and Polarisbreen groups in Ny Friesland and so this classification is applied. It is thus appropriate to rename the original Cape Sparre Formation by dividing it into the Sparreneset and the Klackbergbukta formations. Similarly the Ryss6 Formation as defined by Kulling loses its upper part to make the Backaberget Formation. Thus Krasil'shchikov's (1967) three (Vendian) formations combine to define his Gotiahalvoya Group (equivalent to the Polarisbreen Group of Ny Friesland) and so form the lower group of the Hinlopenstretet Supergroup as applied in Nordaustlandet by Lauritzen & Ohta (1984). T h e r e c a n be n o d o u b t as to the c o r r e l a t i o n w i t h N y F r i e s l a n d as s h o w n in F i g u r e 6.2.

Oslobreen Group. This group, named for the Ordovician and Cambrian formations in Ny Friesland as the uppermost of the two groups comprising the Hinlopenstretet Supergroup, is applied here for the time being pending a decision as to whether the equivalent strata in Nordaustlandet require a distinct group name. It is the uppermost unit 6 of Kulling's Cape Sparre Formation. He described this upper dolomite series (140-200 m) thus: at Sparreneset: Black grey dolomitic mudstone, 40 m with trail marks (originally observed by de Geer 1901, and identified as Helminthoidichnites) and inarticulate brachiopods (Lingulella and Obolus) Grey dolostone, 70-100 m. on Krossoya: Grey to dark-grey dolostone, with trail marks in upper part (Planolites) on Depotoya up to 700 m but poorly exposed. All these fossils have long time-ranges so no precise biostratigraphic correlation could be made, though Kulling took the age to be Early Cambrian. Winsnes (in Flood et al. 1969) described a further section north of Br~vika and measured others. At Sparreneset, in 1974, Harland found the contact with the earlier rocks to be faulted (Hambrey, Harland & Waddams 1981). He thought the nearest analogue in Ny Friesland to be the Nordporten Member of the Valhallfonna Formation of demonstrable Arenig a g e - just across Hinlopenstretet. More fossils had been sought in vain by several parties, but outcrops are between tides and of limited extent. He also noted a fault so that two formations could be present there. The difficulty was resolved by Lauritzen & Yokelsen (1982) who recorded Salterella at Sparreneset, and in Krossoya they also found olenellid tribolites so confirming a late Early Cambrian age. Moreover west of Krossoya they reported an Early Ordovician fauna so supporting Harland's suggestion. Until the matter has been taken further the Early Ordovician unit is referred to informally as the Sparreneset unit to distinguish it from the Early Cambrian Krossoya Formation, the names selected where ages are evident. The result is to match still more closely the successions in Nordaustlandet with those in Ny Friesland. Undifferentiated sections were measured by Kulling (1934) as about 500 m at Sparreneset and by Winsnes (Flood et al. 1969 p.20) at over 1100 m north of Br~tvika near the northwest of Storsteinhalvoya. Sparreneset (informal) formation. Lithologically at Sparreneset this would correlate with the Nordporten Member of the Valhallfonna Formation which in Ny Friesland is of late Canadian (Arenig) age. Biostratigraphically Lauritzen & Yochelson (1982, p.5) reported: 'on small islands northwest of Krossoya, an Ordovician fauna has been found indicating a break in the succession from Middle Cambrian to lower Ordovician time...'. The two unnamed islands near to the northwest coast of Krossoya were mapped by Kulling (1934) as part of his Cape Sparre Formation. Sparreneset is where Harland had noted this unit. No measured section has been published.

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Krossoya (informal) formation. This name is chosen for that part of the uppermost three units of Kulling's Cape Sparre Formation because it appears to be best developed there with a thicknesses of 700-800 m and was described there by Kulling and in 1966 by Winsnes (in Flood et al. 1969) and who collected the specimens identified by Yochelson (Lauritzen & Yochelson 1982) as Salterella. Olenellids were also found so that good correlation is established with the Tokammane Formation of Ny Friesland which, together, indicate a late Siberian (Early Cambrian) age i.e., the Bonnia-Holmia zone. At Sparreneset the succession was described by Kulling (1934) as containing Lingulella and Obolus types and with trace fossils: Helminthoidichnites type and estimated at 110 m in difficult circumstances thus (p. 191): 40 m black-grey dolomite mudstone with trail marks and brachiopods 70-100 m grey dolomite 3 m black-grey laminated dolomites. This may well include part of the Sparreneset formation. The section is clearly incomplete dipping west into the sea. Gotiahalvoya Group (Krasil'shchikov 1967) (equivalent to the Polarisbreen Group of Harland & Wilson 1956). The group comprises three formations: Klackbergbukta (top), Sveanor and Backaberget. Krasil'shchikov (1967) recorded the most detailed available petrographic description of these deposits, only some portions of this are added to this account. Klackbergbukta Formation (Krasil'shchikov 1967). This unit comprises the lower five units of Kulling's (1934) Cape Sparre Formation which he described thus: (5) Upper quartzite series, l l 0 m of variously coloured (red, grey, green, white) quartzite and slaty sandstone at Sparreneset and on Krossoya, also with some grey dolomitic mudstone. (4) Upper Shale Series, 130-140m, pink and grey shales with laminated dolostone and bands of chert (a thin middle quartzite occurring only on Krossoya). (3) Lower Dolomite Series, 120m. At Sparreneset, dark and black-grey dolostone also with some dolomitic limestone on Krossoya and Depotoya. (2) Lower Quartzite Series, 30-40m. White quartzite sandstone only at Sparreneset (subjacent rocks are not exposed possibly being tectonically disturbed). (1) Lower Shale Series, 250m. Green grey and red brown shale SW of Sveanor on S Russoya but more carbonaceous with 10 m dolostone at base resting directly on Sveanor tillite. Other outcrops in Murchisonfjorden and Wahlenbergfjorden were outlined by Winsnes (in Flood et al. 1969), Edwards (1976) and summarized by Harland, Hambrey & Waddams (1993). The age of these rocks has been confirmed as probably Vendian (Knoll 1982a). The dolostones of the upper horizons of the formation are characterized by flaggy parting with thin impersistent layering separated by a few mm of dolomitic siltstones. Krasil'shchikov described centimetre-scale 'convective' ruptures in the lamination, forming regular polygons in plan. Limonitized pyrite occurs higher up. The sandstone clasts are 90%, acid plagioclase dominating orthoclase with a wide range of accessory minerals. Below a sharp boundary are light coloured sandstones. Sveanor Formation (Kulling 1934), 100-168 m. At the type locality, south of Murchisonfjorden, is a diamictite which was the first in Svalbard to be identified unequivocally as a tillite and has been described in detail (Kulling 1934; Edwards 1976; Hambrey 1982). Whereas Flood et al. (1969) included part of Kulling's Rysso Formation, Krasil'shchikov (1967) distinguished that part as his Backaberget Formation (below). This classification is adopted here and so Kulling's Sveanor Formation is approximately retained. Within the formation lateral facies changes are m a r k e d - the typical tillite is best seen at Sveanor in Murchisonfjorden and at Aldousbreen in Wahlenbergfjorden. The diamictites, interbedded sporadically with sandstones, shales and carbonates, range in colour from greyish and green to maroon. The stones comprise: dolostone (50%), limestone (20%) and the rest sandstone, siltstone, granite, granite porphyry, aplite, quartz porphyry, syenite, keratophyre, amygdaloidal basalt, tuff, siliceous sericitic schist, garnet schist, gneisses, phyllite, quartzite, basic volcanic rocks and jasperised chert (Kulling 1934). The proportion of stones is about 5-10%. All shapes especially facetted and striated (up to 10%) stones being common. Krasil'shchikov described the stone petrography in detail noting oncolitic concretions and concretions with katagraphs. The facies vary from massive to weakly bedded diamictite, with conglomerate lenses. The environment of formation is interpreted as

lodgement and waterlain till deposit and ice rafted stones in more distal mudstones, all indicating an interplay of subaerial, subglacial, glaciomarine and glaciolacustrine and fluvial environments. The cessation of glacial conditions is marked by the sharp change to the Klackbergbukta Formation (Harland, Hambrey & Waddams 1993). The till facies were described by Chumakov (in Krasil'shchikov 1964) before he had accepted a glacial origin for such deposits. Many pages are filled with meticulous petrographic descriptions with few petrogenetic (environmental) conclusions. Selected from this account is the estimate that the larger intrabasinal clasts (stones) suggest local origin from the underlying formations down only to a maximum of 500 m. They confirmed Kulling's view that the basic volcanism preceded, but not by a long interval, the deposition of the diamictites. These basic igneous products unlike many of the acidic rocks were not metamorphosed. Attempts to deduce provenance of the stones were not productive. Krasil'shchikov and others correlated these Sveanor rocks with the Polarisbreen rocks acknowledging that Harland & Wilson (1956) had inferred a glacial origin for the same correlation as had Kulling for the Sveanor Formation. But having considered a glacial origin they preferred (with Klitin 1965) a purely tectonic origin for all such deposits. Baekaberget Formation (Krasil'shchikov 1967), 220-290m. Krasil'shchikov separated this unit from the top of Kulling's Sveanor Formation. Hambrey, Harland & Waddams (1981) and Harland, Hambrey & Waddams (1993) followed this scheme, partly because it correlated well with the succession to the west in Ny Friesland. The formation, based on Kulling's 1934 units east of Sparreneset comprises (4) 50 m laminated, cream-weathering, grey, partly cross-laminated dolostone with rip-up conglomerate at the top (3) 40m dark-grey quartzose slate (2) 150 m grey-black shale (15-20 m dolerite sill) (1) no exposure.

Langgruneset member. To the north at Langgrunnodden is a diamictiterhythmite-limestone-sandstone sequence included by previous authors in the Sveanor Formation. However, because of its distinctive composition (dolostone 65%, limestone 15%, quartzite 10% etc.), it appeared to correlate well with the Petrovbreen Member of the Elbobreen Formation in Ny Friesland (Hambrey 1982) and so would be the equivalent of the Early Varanger tillite (Smhlfjord). The diamictite is underlain by dark, cherty shaly limestone (10m), several tens of metres of marls, sandy towards the base overlying the Rysso dolostone. Well preserved acritarchs in the shales yielded to Knoll (1982a): Protosphaeridium sp., Trachysphaeridium spp., cf. stictosphaeridium sp., and Bavinella faveolata (Shepeleva) which indicate a Vendian age. Osagia svalbardica and Vermiculites irregularis had also been reported in Soviet literature (Krasil'shchikov, Golovanov & Mil'shtein 1965).

6.2.2

Murchison Bay Supergroup (Kulling 1932, 1934)

This s u p e r g r o u p n o w c o m p r i s e s three g r o u p s defined by their f o r m a t i o n s as follows, a n d illustrated in Fig. 6.3. Roaldtoppen Group Rysso Formation Hunnberg Formation Celsiusberget G r o u p Raudstup-Salodd Formation Norvik Formation Flora Formation Franklinsundet Group Kapp Lord Formation Westmanbukta Formation Persberget F o r m a t i o n Meyerbukta Formation K u l l i n g ' s (1934) M u r c h i s o n Bay f o r m a t i o n was raised in r a n k to a s u p e r g r o u p a n d r e n a m e d M u r c h i s o n f j o r d e n by F l o o d et al. (1969) in w h i c h K u l l i n g ' s original six 'series' were a d o p t e d as five f o r m a t i o n s b u t classified into two g r o u p s . T h r e e m o r e f o r m a t i o n s were defined at the base o f the succession for rocks t h o u g h t by

NORTHERN NORDAUSTLANDET

Fig. 6.3. Geological map of northwestern Nordaustlandet (after Flood et al. 1966; Gee et al. 1995).

101

102

CHAPTER 6

K u l l i n g to be repetitions by folding o f his lower f o r m a t i o n s a n d c o m b i n e d in the F r a n k l i n s u n d e t G r o u p . A f o u r t h unit was i n t r o d u c e d ( O h t a 1982) to a c c o m m o d a t e f u r t h e r strata below the F r a n k l i n s u n d e t G r o u p a n d to include the K a p p P l a t e n a n d A u s t f o n n a f o r m a t i o n s east o f R i j p f j o r d e n also within the s u p e r g r o u p .

Roaldtoppen Group (Flood et al. 1969). Both constituent formations were argued to be late Riphean (Knoll 1982). Rysso Formation (Nordenski61d 1863; Kulling 1934) was modified by Krasil'shchikov (1967) who, as already noted, placed the upper part of Kulling's Rysso Formation in his Backaberget Formation. The essential Ryss6 Formation middle and lower part is of relatively uniform massive dolomitic facies. Only this part was described as the Rysso Formation by Winsnes (Flood et al. 1969). It is one of the earliest formations to be named in Svalbard but not at first defined. It was probably the whole carbonate development of the Roaldtoppen Group and was thought to be Carboniferous (Nordenski61d 1863): 50-140m light grey dolomite 70-140 m dark dolomitic limestone - dolomite 500 m typical Ryss6 - dolomite (conspicuously oolitic and stromatolitic). The lower part contains yellow-weathered chert, further details were given by Winsnes and by Krasil'shchikov. Krasil'shchikov, Golovanov & Mil'shtein (1965), describing the biostratigraphy, recorded Vermiculites irregular& with a range Vendian through Cambrian. Silicified bituminous limestones with pyritic black shales near the top of the Ryss6 Formation contain vase-shaped microfossils which suggest correlation with the Backlundtoppen Formation in Ny Friesland and the upper Eleonore Bay carbonates in East G r e e n l a n d - all in the Sturtian interval (?750 Ma). Silicified carbonates in lower Ryss6 Formation match the biota of the Hunnberg Formation below, but have Chuaria in addition (Knoll 1982). Hunnberg Formation (Kulling 1934) 400-600m. Consists predominantly of grey black and grey limestones and dolomitic limestones, passing into mudstones, with lighter coloured, and subordinately reddish, limestones in the middle part. There are horizons of chert concretions, chert conglomerates and phosphorite concretions. The upper part of the formation is a shallowing-upward carbonate sequence passing upwards into open coastal marine facies with bioherms and columnar stromatolites overlain by laminated mud-cracked dolostones. The cherts contain microfossil assemblages (Knoll 1982). The restricted lagoonal biota is dominated by Myxococcoides cantabrigiensis Knoll (1982a) and Glenobotrydion aenigmatis Schopf (1968). The open coastal assemblage is a rich variety of plankton including: Chuaria circularis Walcott, Protosphaeridium cf flexulosum Timofeev (sensu Vidal 1976a), Kildinella hyperboreica Tim. K. jacutia Tim. Trachysphaeridium levis (Lopukhin) Vidal, Trachysphaeridium timofeevi Vidal, cf Stictosphaeridium, Phanerosphaerops capitans Schopf, Myxococcoides cantabrigiensis Knoll. Trematosphaeridium holtedahlii Tim. (Knoll 1982). This is a typical Late Riphean microfossil assemblage. The lowest first occurrence of pterospermopsimorphid acritarchs and other complex taxa suggest latest Riphean to Early Vendian (sensu Vidal). Knoll suggested 700800 Ma for the age. Organic geochemistry of the Raoldtoppen Group. In a s t u d y o f dispersed organic m a t t e r in P r e c a m b r i a n deposits o f N o r d a u s t l a n d e t , D a n y u s h e v s k a y a et al. (1970) analysed samples f r o m the R o a l d t o p p e n G r o u p a n d f o u n d t h a t clots o f biogenic c a r b o n a c e o u s material t e n d e d to be c o n c e n t r a t e d in stylolitic structures. T h e y also analysed basal (Vendian) K l a c k b e r g b u k t a a n d B a c k a b e r g e t strata f r o m the overlying H i n l o p e n s t r e t e t S u p e r g r o u p . Many data were tabulated including total organic carbon thus: Klackbergbukta Fm Backaberget Fm Ryss6 Fm (upper member) Hunnberget Fm

0.49% 0.54% 1.07% 0.19%

With transmitted light the organic matter is dark grey through brown to black, in reflected light it is whitish yellow to dark brown. UV luminescence studies showed the dark brown to black matter to be inert and surrounded by an inner luminescent dimly green aureole passing outwards to lighter luminescence. The black material was unevenly pyritized.

Spectroscopic analysis with (many detailed spectra reported) indicated abundant aromatic structures with linked carboxylic C = O groups possibly with (?)chione affinity and a significant aliphatic component of CH2 and CH3. The conclusion was that the material had resulted from the transformation of blue-green algae in the first instance in the Ryss6 carbonates and that at a later stage (a Caledonian event was suggested) fractionation with migration of the lighter hydrocarbon components into the overlying Vendian sandstones accounted for much of the TOC in those formations. In a final comment the authors remarked that their'results paralleled those from North America and Greenland.

Celsiusberget Group (Flood et al. 1969) Raudstup-Siilodd Formation (Kulling 1934; Flood et al. 1969). Kulling described two series in Murchisonfjorden (especially the north coast): (upper) Siilodd series (180-260) of greenish-grey dolomitic siltstones or redgrey shale of Ohta 1982; (lower) Raudstup series (300-440m) of reddish brown and green-grey slate partly carbonaceous and also quartzose with horizons of white quartzose sandstone. Flood et al. (1969) combined these two series into one formation because the lithologies are interbedded and there is no clear boundary between them. The formation occupies the core of the major synclinorium and thicknesses vary greatly from 400 to 2200 m (Ohta 1982). Small scale cross-bedding in the sandstones suggests a wave-dominated sub-littoral environment. Four fining-upward cycles were distinguished in the lower less deformed strata. A metaporphyrite stratum, 0.5 m with plagioclase and mafic phenocrysts (?after pyroxene) occurs in the lower part and is either an intrusive sheet or a lava flow. It is too altered to compare with the widespread Mesozoic dolerites (Ohta 1982). Norvik Formation (Kulling 1934) 350 m is of dominant green-grey to grey sandstone and slaty sandstone dolomite. Multicoloured slates and white quartzite also occur. Ohta (1982) described it as a formation of 900m of lithology intermediate between the overlying shale-rich formation and the thick Flora quartzites with two members: (upper) shale and quartzite alternation (300-700m); (lower) shale-dominated succession (200-550m) and with five cyclic sequences, the quartzite being 7-20 m thick at the base of each cycle. Flora Formation (Kulling 1934) 910m was described by Kulling: as the distinctive lower unit of his Murchison Bay succession, comprising white, pink and green-grey quartzose sandstone. 630m were measured at Floraberget in 13 divisions. Ohta (1982) gave a thickness of 910m divided into three members with detailed petrographic descriptions: (upper) white grey banded ortho-quartzite with thin flasers of shale and sandstone 50-150 m (middle) reddish quartzite with shales and slates and red shale fragments (lower) alternations of grey sandstone and reddish-white quartzite with abundant red shale fragments. There is a basal conglomerate Franklinsundet Group (Flood et al. 1969). The strata described here beneath the Flora Formation were included by Kulling in his Murchison Bay rocks, but assumed to be repetition of the younger strata by folding because of their similar facies. He perhaps exaggerated the steepness of dips in his postulated isoclinal folding. Flood et al. distinguished three older formations combined in the new grouping. Still older strata were distinguished by Ohta (1982: his Meyerbukta formation) and included at first in the Franklinsundet Group. However, Lauritzen & Ohta (1984) named a further Meyerbukta Group. These two new groups may total nearly the same thickness as the two upper groups of the Murchison Bay Supergroup. The upper two formations of the Franklinsundet Group are clearly distinguished from the conspicuous quatzites above (Flora) and (Persberget) below and it is not easy to distinguish the upper two formations as their mutual boundary is not well exposed. Kapp Lord Formation, 1000 m, in which a detailed succession of 43 units recorded by Gee (Flood et al.) comprising mudstones (various colours) quartzites, limestones and shales in that order of abundance. Westmanbukta Formation, 625 m is similar to Kapp Lord Fm. but with less limestone and more siltstone and fine sandstone. Persberget Formation is characterized by massive white and grey quartzite with subordinate grey shales and ripple marks and ferruginous spots. No complete section was measured and this may account for the lower part being underestimated (Flood et al.) which was later distinguished as the Meyerbukta Formation. Meyerbukta Formation (Ohta 1982). To the north of Kapp Lord and Westmanbukta, the large island of LAgoya yielded to Ohta (1982) a

NORTHERN NORDAUSTLANDET thickness of shales, east of and below the Persberget quartzites. The shales are in places calcareous and grey limestones occur. Ohta claimed 1400m in total for this Meyerbukta Formation. He also (1982 p. 29) argued for a series of megacycles into which the above successions could be divided. Djevleflota Formation (Ohta 1982; Gee & Teben'kov 1996). In central Nordaustlandet in the outcrops between Austfonna and Vestfonna and south of Rijpfjorden to inner Wahlenbergfjorden, Ohta had described three units: Innvikhogda, Djevleflota and a basal quartzite. The area was mapped in greater detail (Gee & Teben'kov 1996) which resulted in a revised stratigraphic scheme.The Djevleflota Formation was accepted as correlating with Ohta's Meyerbukta Formation in the west and at the base of the Murchison Bay Supergroup. In this area it was seen to rest unconformably on the Svartrabbane Formation correlated with the Kapp Hansteen Group. This formation is essentially the same as the Austfonna Formation originally mapped here (Flood et al. 1969).

6.2.3

Kapp Hansteen Group

Botniahalvoya. (Kulling 1932, 1934; Ohta 1982; Lauritzen & Ohta, 4G, 1984). The group comprises at least the Norgekollen and Gerardodden formations (introduced informally here to define the Kapp Hansteen Group), and probably includes the Svartrabbane Formation (Gee & Teben'kov 1996). Kulling (1934, p. 221) summarized his Cape Hansteen Formation as 'of considerable but little known thickness. Grey-green to green porphyry dominates the formation, but there are also violet-grey to red-grey porphyry, grey quartz-porphyry, greengrey quartz-phyllite (mostly more or less rearranged pyroclastic material), agglomerate, and conglomerate'. He gave detailed descriptions area by area. Flood e t al. (1969) described the petrographic types in the volcanogenic Kapp Hansteen succession. In spite of their uncer tainity as to the relative ages of the Kapp Hansteen and Brennevinsfjorden units they were clear that the magmatic rocks best seen around Norgekollen were later, being intrusive into the fragmental Kapp Hansteen succession. Ohta (1985) described the geochemistry of the igneous rocks in detail. He concluded that 'the porphyrites are calc-alkaline acid andesites and dacites of medium to high KaO type'. Two meta-diabase types are (i) of low K20 and high Fe tholeiite and the main body (ii) are acid andesites. Basic dykes suggest island arc volcanism and all are referred to continental rather than oceanic types.

Norgekollen (quartz porphyry) Formation. This is the large body cropping out at Norgekollen but representative of other quartz porphyry intrusions in the peninsula. Whereas it intrudes the rest of the Kapp Hansteen succession and the Brennevinsfjorden Group it is in turn intruded by the Kontaktberget granite in which it also occurs as xenoliths. The porphyries contain metasedimentary xenoliths. No such intrusions are known in the Murchison Bay Supergroup. Quartz porphyry clasts occur in a basal conglomerate in the Murchison Bay sequence due east of Hansoya. Flood et al. (1969), following Sandford (1950) reported that quartz porphyries are distinguished by smoky coloured quartz (up to 15%) phenocrysts, often corroded, (1-3mm diam) 3-7cm -2 and with sharp contacts. Somewhat larger grey, white and pink feldspar (albite-oligoclase) phenocrysts up to 25% occur in a fine groundmass. The composition is of rhyolitic to dacitic composition and a general potash-calc-alkaline affinity. Derivation from the thick continental crust has been inferred (Gee et al. 1995). Three facies occur; massive, sheared, and folded even within one body so that their regional significance cannot readily be inferred. Ohta (1982) referred to the rocks as phyllitized rhyolite. A later schistosity penetrates all these lithologies (Flood et al. 1969, p. 61). This is consistent with the schistosity being part of the post-Hecla Hock (Caledonian) deformation and not to be confused with the pre-Kapp Hansteen Group deformation to be considered below (and p. 109). The minor upheavals associated with the magmatism would account for the local angular unconformity that follows. No great discordance is evident because of the persistence of the succession from east to west. The age of the quartz-porphyries has been estimated at 766 + 87 Ma by Rb-Sr isochron (Gorochov et al. 1977), and a revised age of 970 Ma is expected from the same authors (Ohta 1992).

103

Gerardodden Formation. The stratified volcaniclastic sequence follows with five formations as outlined by Ohta (Gee et al. 1995). Agglomerate, tuff breccia and lava formation, c. 1 km. These include units 4 to 7 (downwards) as mapped by Ohta: (4) ignimbrite; (5) andesite; (6) porphyrite; (7) tuff, breccia and agglomerate. (8) Shale formation c. 50 m This contains tuffacious laminae and is of intermittent occurrence. Tuff and tuffaceous sandstone c. 10 m. These are finely laminated tufts often graded with sandy intercalations and locally with breccias. (9) Columnar jointed porphyrite c. 10m. This massive grey rock is of rhyodacite composition and appears as a conformable lava fow. (10) Basal conglomerate formation up to 20m. These conglomerates are clast supported with monomict basal beds dominated by quartzite clasts up to 1 m in diameter and well rounded at the base but increasingly angular and polymict upwards. Because of the immense variety of volcanic facies and the fine grain of much material, chemical analysis have been used in preference to petrography to characterise the rocks. Ashes and tufts are abundant and 'many of the non fragmental rocks were interpreted as lava flows' (Flood et al. 1969).

Rijpdalen area in Central Nordaustlandet Svartrabbane Formation. Gee & Teben'kov (1996), from further mapping of the outcrops between Vestfonna and Austfonna, defined a new formation with a basic volcaniclastic content already described by Teben'kov (1983) and Ohta (1985); they are interbedded with phyllites and quartzites. Gee & Teben'kov correlated this new unit within the Kapp Hansteen Group. On mapping it was found to rest unconformably on the Helvetesflya Formation of the Brennevinsfjorden Group.

6.2.4

Brennevinsfjorden Group

The formations of the Brennevinsfjorden Group are distinguished in two main areas. To the west of Laponiahalvoya is the type outcrop on Botniahalvoya and to the east are the outcrops of Rijpfjorden and Prins Oscars Land. To qualify as a group it must be defined by its constituent formations. These are three, as yet unnamed, units in the western outcrop as listed below.

Western outcrops. The unit as described by Flood e t al. 1969, p. 53), comprises a m o n o t o n o u s sequence of interbedded quartzites, siltstones and shales. The quartzites are only rarely more than a metre thick. The bedding dipping steeply to the east in the type area mainly coincides with the cleavage. Ripple marks and crossbedding occasionally signal inversion of strata. The quartz has slight undulatory extinction. Ohta (1982 p. 7) recorded 'a 3000m thick areno-argillaceous succession'; Lauritzen & Ohta (1984) referred to 4500 m in the type area. A narrow and distinct hornfels with large idioblasts of andalusite, poikiloblastic staurolite and garnet develops within 30 m of the contacts with the porphyritic gneiss and granite. Strong cleavages with the metasediments show conformable trends with the margins of the granite-porphyritic gneiss masses. Ohta's (1982) detailed observations in Botniahalvoya are significant both in determining that the group is older and not younger than the Kapp Hansteen Group and in identifying a basal conglomerate between them. Three unnamed formations have been distinguished on Botniehalvoya by Ohta (Gee e t al. 1995): Upper sandstone shale formation Middle quartz shale formation Lower shale sandstone formation

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Rijpdalen area in Central Nordaustlandet Helvetesflya Formation (Gee & Teben'kov 1996). In this area, further mapped by Gee & Teben'kov the lower formations of the Murchison Bay Supergroup, once approximately the Austfonna Formation and now established as the Djevleflota Formation, rests unconformably on the Svartrabbane Formation, which in turn has extensive unconformable contacts with the dominantly phyllitic shale and slate Helvetesflya Formation. This has a penetrative, finegrained sericitic schistosity and a superimposed crenulation in an isoclinally folded sequence. The map suggests that the Helvetesflya and Svartrabbane formations are isoclinally folded together. The Helvetesflya Formation is in contact with extensive outcrops of granitic augen gneiss (at Ringghsdalen). This gneiss as well as the above formation is cut and/or metamorphosed by the Rijpdalen-Winsnesbreen granites which were suspected to be coeval with the Laponiahalvoya granites and confirmed as 'Grenville age' based on U-Pb zircon age data (Johansson in Gee & Teben'kov). This would suggest that the whole of the outcrops from the east would also be Proterozoic basement.

North central Nordaustlandet The Kapp Platen Formation at Kapp Platen was mapped in some detail by Winsnes (Flood et al. 1969). This unit has been variously correlated with the Austfonna rocks but in the map of Gee et al. (1995) it was shown as Brennevinsfjorden Group.

6.3 6.3.1

Subjacent metamorphic complex Evolution of ideas

Parry is credited in 1928 for classifying the granites and gneisses together as 'primitive rocks'. Nordenski61d (1863) listed seven formations from Nordaustlandet of which the lower four were (4) (3) (2) (1)

Ryss6 Formation (which he thought might be Carboniferous) Hecla Hock Formation Crystalline limestone and dolomite Gneiss with granite veins and dykes.

He sampled the lowest unit on extensive sledge journeys along the north coast of Nordaustlandet. These 'crystalline' rocks were regarded as Archean basement and were included as Urgebirge in Nathorst's synthesis (Suess 1888 and Nathorst 1910) though he expressed doubt as to the certainty of this conclusion. De Geer (1909) took the same view. A similar opinion regarding the crystalline complex of north western Spitsbergen prevailed until Holtedahl (1914, 1926), in northwest Spitsbergen,argued that the metamorphism resulted from remobilization during the Caledonian orogeny. The status of the Nordaustlandet complex was then in doubt but it differed from the northwest in having an 'unmetamorphosed stratified cover'. Sandford (1926) inclined to the view that the granites were younger. Kulling, who had access to Nordenski61d's material, in 1932 (p. 132) tabulated beneath his Kap Hansteen formation. 'Prim~irt Liggende Ok~irt' (primary layers unknown). Sandford (1950, 1956) began to suspect, and later postulated, an unconformity between the Cape Hansteen rocks and the subjacent metamorphic complex as did Orvin (1940, p. 8) 'there can be no doubt that the Barents Sea shelf forms a continuation of the Fenno-Scandinavian Archean Shields'). That connexion was later in doubt as the postulated Iapetus ocean divided the two areas (Harland & Gayer 1972); but the concept of a (Laurentian) Barents Craton was not thereby undermined. Hamilton & Sandford (1964) showed that Paleozoic thermal activity was extensive from the earliest isotopic age determinations in Svalbard. Nevertheless the dominant view was for a basement to the Proterozoic strata (e.g. Sokolov, Krasil'shchikov & Livshits

1968a) and an ancient Barents shield was postulated to bound the Hecla Hock Geosyncline to the east. We thus depend on the new series of observations by Norsk Polarinstitutt geologists mainly from helicopter reconnaissance sorties and further work by their colleagues in Sweden and Russia. Flood and Gee (Flood et al. 1969, pp. 97-120) described their sub-'Botniahalvoya' complex as of granitic gneisses and migmatites, clearly post-Botniahalvoya in age from their contrasting relationships and some metasomatism. However their description of the supracrustal inclusions therein refers to occasional extensive stratiform rocks, dominantly pelites through to quartzites, and marbles with associated amphibolites. The amphibolite facies of these inclusions contrasts with the greenschist facies of the overlying Brennevinsfjorden rocks. At that time a Caledonian event was preferred. Gee et al. (1995) mentioned that 'pre-Grenvillian basement' is suggested by U - P b data on biotite schist xenoliths within the Laponiafjellet granite. Also augen gneisses at Fonndalen in central Nordaustlandet gave a zircon age of 1048 4-27 Ma with monazite suggesting metamorphism around 960 Ma and some latest Silurian evidence of 412 Ma. Gee &Teben'kov (1996) mentioned a 'Grenvillian' age for the Rijpdalen granites (communicated by Johansson) which would seem to settle the matter. That is to say that the granites and related migmatites of central (and therefore eastern) Nordaustlandet are essentially coeval with those of western Nordaustlandet in Laponiahalvoya so that the whole complex would be Proterozoic, but rejuvenated in some degree in Paleozoic time. Whereas much of the inclusion material may be Brennevinsfjorden Group paleosome, the amphibolites, some of likely sedimentary or at least stratiform origin and others possibly intrusive, do not match the overlying rocks and so are candidates for preBotniahalvoya, i.e. pre-Brennevinsfjorden rocks.

6.3.2

Migmatic and magmatic components

In the early accounts (e.g. Sandford 1926) emphasis was given to the contrast between grey, foliated granites and gneisses, and pink granites. This sub-section concerns the former which are earlier than the late-tectonic plutons (Section 6.4). This large tract of migmatic rock has been named the Duvefjorden Complex (Teben'kov in Gramberg, Krasil'shchikov & Semevskiy 1990). There are two large outcrop areas of these migmatitic gneisses (Flood et al. 1969). In the west: most eastern Laponiahalvoya and Sjuoyane are so mapped. In the east, from Duvefjorden and eastern Rijpdalen, the whole of the eastern half of the north coast outcrops of Nordaustlandet is similarly mapped. West of Rijpfjorden Hjelle (in Flood et al. 1969, p. 103) generalized their findings as follows: Quartz monzonitic rocks with considerable amounts of supra-crustal inclusions occur and at some places with transitions into migmatic gneiss. The modal composition of the migmatite metatect does not differ from that of the average quartz monzonite. The rocks are coarse-grained, grey, hypidiomorphic to porphyritic texture, with phenocrysts of K-feldspar (often microcline and microperthite). Texture varies from slight to well foliated gneiss. Plagioclase is An20m0 and often there are Rapakivi type rims. Quartz shows undulatory extinction and accessories are biotite, muscovite, titanite, apatite, zircon and iron ores. Whereas to the south the rocks are less foliated, and show facies transitional to the Brennevinsfjorden granite, to the north (Nordkapp and Sjuoyane) gneissic structure is typical. Quartzite inclusions with up 65% quartz, epidote and some titanite obtain; mica schist inclusions comprise quartz, albite, biotite; amphibolite inclusions have quartz, oligoclase to andesine, hornblende; and almandine, calcareous inclusions have quartz, calcite, diopside, wollastonite. The gneisses often contain lenses of tourmaline-bearing muscovite. East of Rijpfjorden, Flood & Gee (in Flood et al. 1969 pp. 105-120) suggested that the exposures from Rijpfjorden through Duvefjorden and to the extreme northeast may be just the northern fringes of a large outcrop area extending beneath the ice at least to Isispynten.

NORTHERN NORDAUSTLANDET At the contacts between the low-grade Botniahalvoya Group and the granites and migmatites there is a sharp transition to biotite- and garnetbearing schists, with hornblende in the more basic facies. For example at Innvika in Duvefjorden chlorite-muscovite assemblages in Austfonna (Meyerbukta Group) rocks occurring at a distance of 500 m from the contact give way to biotite-muscovite schists. Within 100 m garnet develops with feldspathic quartz lenses in the schistosity and in the immediate contact zone are staurolite-andalusite-biotite-muscovite~zluartz assemblages in tightly folded structures in which schistosity penetrates the contact zone as well as pegmatite veins. Where the contact is with homogeneous igneous rocks there is generally cataclastic deformation. The more detailed account (p. 108) favours intrusion of granitic magma during deformation but an envelope of quartz monzonite probably solidified first at the contact. Several other such contact phenomena were described in detail (pp. 108-112). The migmatites, gneisses and syno-orogenic granites show a great variety of facies, ranging from little or no foliation or inclusions to highly foliated gneiss with abundant, often large inclusions. A typical composition is 30% quartz, 30% plagioclase, 30% K-feldspar and 10% micas with apatite and zircon. There is an overall similarity of composition throughout, modified only by the various types of inclusion. Evidence of post-magmatic strains abound from cataclastic textures, strain-shadowed quartz, and augen gneisses (augen being typically microcline).

6.3.3

Supracrustal inclusions

Flood et al. (1969, p. 61) reported that their Botniahalvoya Group 'base is not known, and no evidence of an underlying old preCaledonian basement has been found'. Nevertheless (p. 62) 'observations have confirmed a general occurrence of amphibolites east of Duvefjorden as well as within the Austfonna Formation within the migmatite border' which Flood inclined to indicate, by the abundance also of feldspathites, a possible correlation with Harkerbreen Group in N y Friesland. Whereas feldspathites (i.e. metamorphic rocks with >50% feldspar, Wallis et al. 1968, 1969) abound in all the Lower Hecla Hoek of Ny Friesland (Stubendorffbreen Supergroup) amphibolites do not characterize the Planetfjella Group which is correlated here with the Kapp Hansteen Group. They are however abundant in the underlying Harkerbreen Group of N y Friesland so that it is pertinent to enquire as to the abundance of amphibolites within the sub-'Botniahalvoya' migmatites. Amphibolites were reported as a conspicuous element in the metamorphic complex at Isispynten (Sandford 1954) associated with the grey granites (probably migmatitic) in a sedimentary series. It is noteworthy that there is no match for the gabbro-noriteanothosite of Storoya and Kvitoya (p. 17) which appear to be higher in the sequence and possibly Caledonian (Ohta 1978).

6.4

Late tectonic plutons

Two main areas of granite outcrop have been mapped. I n the west is Laponiahalvoya and in the east, Prins Oscars Land. Laponiahalvoya exposes two adjacent bodies. (1) On the west side (east of Brennevinsfjorden) is the Kontaktberget granite. This was so named by Kulling and by Gee et al. 1995. It was also referred to as the Brennevinsfjorden granite by Flood et al. (1969). Further east is the larger outcrop of the Laponiafjellet granite and migrnatite which also forms the islands to the north. There is an isolated outcrop to the southeast south of Sabinebukta mapped by Flood et al. as a subglacial extension of the Kontaktberget granite round the south of the Laponiafjellet outcrop and northeast into some small islands. This is referred to as the Sabinebukta granite. To the south and adjacent to it is a Sabineberget acid rock, probably a Kapp Hansteen quartz porphyry. (2) The eastern granites crop out in Prins Oscars Land. The main body e x t e n d s along the east coast of Rijpfjorden south of Platenhalvoya and again further south near the head of Walhenbergfjorden. There is a further outcrop to the east south of

105

Duvefjorden. These rocks were all mapped (Flood et al. 1969) as adjacent to and probably penetrating synorogenic granites and migmatites which then develop extensively to the east. Kulling (1934) first noted that the granites were not affected by Caledonian folding. Isotopic ages of the granites are the youngest in the area i.e. 400-350 (Hamilton, Harland & Miller 1962; Krasil'shchikov 1965, Winsnes 1965). However, later isotopic work (Gee et al. 1995) requires a radical reapraisal. Hjelle (Flood et al. 1969, pp. 121-128) described the two postorogenic granites': Brennevinsfjorden in the west and Rijpfjorden in the east. The most frequently observed mineral association is quartz-microcline-plagioclase (albite-oligoclase)-biotite-muscovite. Nordaustlandet granites are more alkaline, less calcic and femic than analogous granites in N y Friesland and Northwest Spitsbergen. This is not surprising with the new evidence that they were not coeval.

6.4.1

Laponiahalvoya granites (Hjelle in Flood et al. 1969; Gee, Johansson, Ohta et al. 1995)

The Kontaktberget granite outcrop, if continued beneath fjord and ice cover, appears as an arc with the Botniahalvoya outcrop on the outside (W and S) and the Laponiafjellet foliated granite and migmatic complex on the inside to the east and north so disposed as a broad antiform plunging to the south. The Kontaktberget granite is light grey to red, medium grained, part porphyric, somewhat foliated and cataclastic. Quartz (30-35%) exhibits undulatory extinction bluish with brittle deformation; K-feldspar (30-35%) occurs mostly in medium grained ground mass but also as phenocrysts up to 3 cm long. It is often perthitic and with microcline twinning. Plagioclase (0-20%) is often sericitized with An from 5 to 15%. Biotite (10%) and muscovite (5%) occur with tourmaline, fluorite, ilmenite, zircon and apatite. Intrusive contacts are observed with Kapp Hansteen Group strata exibiting fine-grained marginal facies. Such relationships seen to the east at Sabineberget contradict Sandford's (1950) unconformity interpretation based on air photographs. Anomalous compositions by assimilation of micaceous and calcareous metasediments occur. An occasional orbicular facies is rich in tourmaline. The Laponiafjellet granite is a coarse porphyrite variety, almost an augen gneiss. The foliation and shearing as seen against the quartzmonzonite of the migmatic complex is related to the final stages of the emplacement orogeny rather than as flow during intrusion. The granites are thus late rather than post-orogenic. The composition is quartz 25-30%, Kfeldspar 25-30%, plagioclase 20-25%, and micas 10-15% and accessory minerals parallel those in the Kontaktberget granite. Whereas the Kontaktberget granite has distinct xenoliths near the margin, the Laponiafjellet granite with larger xenoliths merges into migmatite complex with large paleosome rafts both pelitic and psammitic, and occasional marble. Chemical composition of both granites suggests an origin from melting of upper crustal rocks. The Nordkapp granite. The northernmost island of Svalbard, north of Nordaustlandet was sampled by Hjelle (1966) who classified it with the second of his divisions (i.e. with the late tectonic plutons described above and distinct from those that follow. The structural relationship has not been determined. There is one record of isotopic age. Hamilton & Sandford (1964) by Rb-Sr on feldspar obtained 537 Ma. This leaves the age of the intrusion open. However, by analogy with related granites in Nordaustlandet an early Neoproterozoic origin seems probable with later reheating.

Isotopic ages.

Isotopic ages (recalculated) were by Krasil'shchikov

et al. (1964) K - A r on biotite 388 and 393 M a and on whole rock 413 and 428 M a from the southwestern outcrop and by Gayer et al.

(1966) K - A r on biotite 390-399 M a and on muscovite 443 Ma. On the time scale adopted for this work the biotite ages are Early to Middle Devonian and thus the shearing phase could be Late Devonian (i.e. Svalbardian). However, Johansson & Balashov (in Gee et al. 1995) reported zircon ages in the Kontaktberget granite of 939 + 8 and of the Laponiafjellet granite of 961 4- 17 Ma. This is consistent with the contact evidence that the Laponiafjellet

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rock was earlier than the Kontaktberget granite, but the difference between the apparent ages may not be significant. The implications of these results are far-reaching, if the zircons crystallised with the granites and are not inherited. Because all the other ages are Silurian-Devonian, which would then indicate a major Paleozoic regional thermal event to reset all but the zircon crystals and some R b - S r ratios. If this be the case it calls into question the whole area of granites and migmatites to the east where already several values around 600Ma indicated some Precambrian event in addition to the ubiquitous Silurian early Devonian thermal activity.

6.4.2

The pink or red rock is of normal granitic composition with hypidiomorphic, medium-grained and often shear structures. Post-magmatic strain is evident from the undulatory extinction of quartz. Muscovite exceeds biotite and accessories include iron hydroxides and fluorite. Feldspar margins and fissures are embayed by quartz. The K-feldspar is typically microcline-microperthite, the plagioclase is Ans_~0. Biotite content increases near contacts and xenoliths as does more calcic palgioclase. Intrusive sharp contacts with supracrustal rocks are common, but may be transitional with some migmatites. Xenolith distribution gives the impression of an unroofed batholith. Moreover, the pink granite also intrudes homogeneous grey augen-gneiss approximating to quartz diorite, as do apophyses of aplite and pegmatite. A typical sequence is: (a) supracrustal relicts, (b) synorogenic quartz monzonitic gneisses, (c) late-orogenic Rijpfjorden granite, (d) aplite and pegrnatite dykes. The dykes are occasionally foliated and thus are also late-tectonic. K - A r isotopic determinations by Krasilshchikov et al. 1964 (recalculated) on whole rock gave 362, 362, 347, 352, and 438 Ma, on muscovite 387Ma; and on biotite 377Ma. These are all Silurian-Devonian ages and again suggest final Devonian stability. On the other hand Gee & Teben'kov (1996) reported a 'Grenvillian' age in zircon by Johanssen from the Rijpdalen granite. No zircon determinations are available.

6.5.1

Minor igneous bodies Acid intrusions

The granitic, aplitic and pegmatitic dykes belong to the Late tectonic granitic episode treated above.

6.5.2

6.5.3

Dolerite sills and dykes

Relatively unaltered dolerite dykes and sills abound especially in western Nordaustlandet and Hinlopenstretet. They are most probably part of the Cretaceous igneous episode which was extensive throughout most of eastern Svalbard. They can best be dated where related to lavas in K o n g Karls Land to the south and are discussed in Chapter 5.

The Rijpfjorden, Rijpdalen and Duvefjorden granites

Outcrops of this facies are more complex, extending in a N - S strip from the east of Rijpfjorden south through Rijpdalen and with outliers east of Wahlenbergfjorden and south of Duvefjorden. Contacts are with both Botniahalvoya and younger Meyerbukta formations and with the large eastern migmatite complex (Hjelle in Flood et al. 1969).

6.5

determinations. If they are the product of island arc magmatism of Neoproterozoic or Paleozoic age the Barents Craton concept as including the Duvefjorden Complex is challenged.

Basic layers to northeast

In the northeasternmost corner of this study area (Nordmarka, Storoya and Kvitoya) occur basic igneous complexes which are not matched elsewhere in Svalbard (Hjelle, Ohta & Winsnes 1978, Ohta 1978). Basic stratiform rocks appear to be higher in the sequence than the relatively flat-lying migmatic gneisses. Moreover, structurally and petrographically the basic rocks appear to be syntectonic (with the migmatites). Their calc-alkalic and tholeiitic compositions suggested thick continental terranes that would be consistent with a Caledonian foreland to the east. Ohta (1978) in particular described the detailed mineralogy and geochemistry of the Storoya gabbro-diorite complex. Whether the strata were formed as flows or sills near the surface or as part of 'an island arc setting with a thick continental crust' as Ohta suggested is an open question. He argued for a Caledonian origin in 1978 a view that might be modified in the light of later extensive Proterozoic age

6.6

Summary of isotopic ages

All numerical values in this list are in Ma. Analytical details with estimated errors etc. must be obtained from the original papers. Such early data were abstracted up to that time by Gayer et al. 1966. The values given here have been recalculated as necessary according to 1976 constants. They are plotted on the map (Fig. 6.4) on which the following numbers give the references. (1) Hamilton & Sandford (1964) by Rb-Sr at Oxford: from biotite in gneiss at Isispynten 358, 411, 415; from 'Southern Land' muscovite in granite and aphite 373, 378; from Nordkapp feldspar in granite pegmatite 537; from Rijpdalen schist, biotite 618, muscovite 636, whole rock 581. (2) Krasil'shchikov, Krylov & Aljapysev (1964) by K-At at Vinbukta on the E coast of Rijpfjorden, whole rock grey granite 362, pink granite 362, porphyritic granite 347, granosyenite 352, muscovite in pegmatite 388; Rijpfjorden (Wordiebukta) biotite in biotite gneiss 438; from E coast of Brennevinsfjorden (Zeipelbukta) rapakivi granite whole rock 413, rapakivi granite biotite 388; medium granite biotite 393; granite in coastal gravel whole rock 428. (3) Gayer, Gee, Harland, Miller, Spall, Wallis & Winsnes (1966) compiled previous Svalbard determinations including the above with some analytical data etc., converting Russian to western constants and in addition reported from Nordaustlandet material collected by Winsnes determined by K-Ar from north Laponiahalwya west Beverlysundet on musconvite from granite pegmatite 443; from altered biotites in unfoliated pink granite 399; from head of Wahlenbergfjorden on muscovite from foliated granite 420. (4) Krasil'shchikov (1970) also from head of Wahlenbergfjorden by K-Ar whole rock 376. (5) Edwards & Taylor (1976) from a large granite boulder in the Vendian tillite at Aldousbreen north of Wahlenbergfjorden obtained 1275. (6) Gorochov, Krasil'shchikov, Mel'nikov & Varsavskaja (1977) Reported a whole rc-:k Rb-Sr age of 766 from (probable Kapp Hansteen volcanics in) Botniehalv~ya. Because of the high initial strontium content this was later revised to 970 (see Ohta 1992 and Gee et al. 1995). (7) Ohta (1982) reported a whole rock Rb-Sr determinations in the lower Murchison Bay Supergroup of 520. (8) Lauritzen & Ohta (1984) reported Rb-Sr determination on whole rock from Nordre Repoya of c. 600. (9) Ohta (1992): compiled previous Svalbard data making corrections for 1976 constants as necessary. In addition he reported a whole rock Storoya age by K-Ar of c. 600 and gave a revised age of 970 from the original 786 whole-rock Rb-Sr determination from the ?Kapp Hansteen acid rocks of Botniahalvoya. (10) Gee, Johansson, Ohta, Tebenkov, Krasil'shchikov, Balashov, Larionov, Gannibal & Ryungenen (1995) gave details of new U-Pb and Pb-Pb determinations of zircons, by laboratories in Stockholm and Apatity, with selected ages of the Kontaktberget granite 939+8 and of the Laponiafjellet granite 961-4-17 which in view of uncertainties were taken as c. 950. Also noted were tentative ages by Larionov from migmatite rafts in NE Laponiahalvoya by Pb-Pb indicating a pelitic paleosome at c.1600 and also tentative zircon results from the Brennevinsfjorden Group at c. 1500. (11) Krasil'shchikov, Kuno & Sirsova (1996) reported earlier unpublished age determinations on metagabbros from Storoya c. 677 Ma and for Kapp Laura, 442 Ma. (12) Gee & Teben'kov (1996) reported, without details, on 'Grenvillian' age of the granites of southern Rijpdalen based on U-Pb zircon determinations and plotted on their maps the value 1050Ma.

NORTHERN NORDAUSTLANDET

107

Fig. 6.4. Summary of isotopic ages from Nordaustlandet. Outcrops mainly from Gee et al. (1995), and Gee & Teben'kov (1996). Sources of data indicated by numbers in parentheses are as follows: (1) Hamilton & Sandford (1964); (2) Krasil'shchikov, Krylov & Alpapyshev (1964); (3) Gayer et al. (1966); (4) Krasil'shchikov (1970); (5) Edwards & Taylor (1976); (6) Gorochov et al. (1977); (7) Ohta (1982); (8) Lauritzen & Ohta (1984); (9) Ohta (1992); (10) Gee et al. (1995); (11) Krasil'shchikov et al. (1996); (12) Gee & Teben'kov (1996).

6.7

Structure of Nordaustlandet

From the structural reconnaissance reported by Gee (Flood et al. 1969) it seemed that an igneous-migmatic contact rather than

Earliest maps typically show the few rock types recorded to be separated by faults. The first detailed structural traverse was recorded by Kulling (1934) in which the Murchison Bay strata were steeply f o l d e d - mainly upright but with an eastward-verging recumbent fold rooted at Floraberget. Subsequent work by Ohta (1982) showed that the repetition of strata required for KuUing's isoclinal interpretation was indeed better explained by the downward succession into similar but still older strata. Therefore the easterly vergence cannot be sustained. Sandford (1956), using Kulling's data and interpreting from air-photographs plus his own and other available observations, published the first structural map of northwestern Nordaustlandet (Fig. 6.5). It makes little structural difference whether the sub-jacent complex was formed earlier or later than the Hecla Hoek sequence. Sandford mapped a nearly straight N-S shear zone just west of D u v e f j o r d e n - his 'Dove Bay Fault'. He noted that no Hecla Hoek strata are known east of it. It could certainly fit later hypotheses of strike-slip displacement. It would also be consistent with the evidence ofpost-pluton shear in the granites. However, Gee (in Flood et al. 1969) did not observe any post-migmatite displacement there. There are minor shear zones in which porphyritic granite has developed into augen-gneiss. From further fieldwork Gee et al. (1995) seeking evidence i.a. for terrane boundaries did not report any other major shear zone in Nordaustlandet. Such a Duvefjorden Fault was mapped east of Duvefjorden, trending N N W SSE, by Krasil'shchikov (1973) east of which he mapped a pre-Riphean basement, later referred to as the Duvefjorden Complex. However, Krasil'shchikov et al. (1996) marked only a N-S anticline just east of Duvefjorden within the North East uplift (Fig. 3.10).

an unconformity separates the subjacent complex from the supracrustal strata. However, from the discovery that the westerly granite plutons, at least, yielded early Neoproterozoic zircons a new model appears to emerge (Gee et al. 1995). A Proterozoic migmatic-magmatic invasion of metasediments was somehow subsequently altered thermally so that K - A r and R b - S r ages therein appear to be midPaleozoic. This somewhat enigmatic result, albeit with work still in progress, is addressed in Section 6.8 below. Three east-west sections (Flood et al. 1969, p. 68) show mainly open upright folds without great amplitude so that coeval strata have wide distribution. Many faults plotted on a map (p. 94) were shown as vertical. The faults and fold axes are generally N S or N N W - S S E and are interpreted as strike-slip both dextral and sinistral. The migmatic-magmatic (crystalline) areas tend to be positive and determine the main fold structure which is of broad anticlines plunging south with the youngest strata to the west and south. Gee's syntheses noted that the Nordaustlandet structure is dominated by a Caledonian (post-Canadian/pre-Pridoli) fold system. The cleavage, dipping steeply eastwards, is axial planar to the folds which are asymmetric towards the west i.e. as in Ny Friesland and verging westwards. The Hinlopenstretet synclinorium gives the strata on both sides a similar sequence with the oldest rocks away from it. One group of faults is related to the E - W compression of the Caledonian folding with srike-slip displacement dextrally on W S W - E N E trends and sinistrally on W N W - E S E trends. The youngest strata, the Sparreneset formation, dip steeply west into Hinlopenstretet at both Sparreneset and west of Krossoya. The oldest strata appear east of Lady Franklinfjorden on the western flank of the Vestfonna antiform which plunges south beneath

108

CHAPTER 6

Fig. 6.5. Outline geological map of Nordaustlandet and adjacent areas of Ny Friesland illustrating the major structural featues, mainly from Gee (in Flood et al. 1969). Vestfonna. In its core to the north is the Laponiahalvoya intrusion. Not enough is known of the structure further east. It is possible that an analogous synform could occupy Nordenski61dbukta. Then further east there is the option to continue the gentle fold pattern with a Kapp Platen antiform or to treat that as the western edge of the Duvefjorden Complex-Barents Craton (Fig. 6.5). Other dominantly strike-slip faults trend NNW-SSE and N N E SSW. Carboniferous strata are not thereby displaced so that they may have formed during the Late Devonian Svalbardian movements. The Murchison Bay Supergroup strata were undeformed prior to the Caledonian folding. Gee's (1969) discussion of the relationship with the Botniahalvoya rocks was overtaken by the 1982-1984 stratigraphy already recounted so that there must be an unconformity beneath in the Murchison Bay Supergroup and another break beneath the Kapp Hansteen Group. The E-W sections south of Kapp Platen sketched by Winsnes (Flood et al. 1969, p. 66), show an open (upright) fold structure without sensible vergence and apparently cut by the Rijpfjorden granite. Assuming that the latter is early Neoproterozoic then the folding might be part of the tectonism represented by the Botniahalvoya unconformity. This might confirm the correlation of the Kapp Platen strata within the Brennevinsfjorden Group. Correlation with Ny Friesland is suggested in the Chapter 7 and discussed in Chapters 12, 13 and 14.

6.7.1

A Barents Craton

Throughout the fluctuating interpretations of the role played by Phanerozoic diastrophism in Nordaustlandet, there has been a

persistent opinion that the Duvefjorden Complex could be part of a Precambrian shield. This could be confirmed by further isotopic investigations in eastern Nordaustlandet. If it be so then Barentsia would not be part of Baltica but rather an extension of Laurentia and separated by the ensialic Hecla Hoek aulacogen from the East Greenland part of Laurentia (as discussed further in Chapter 12).

6.8

The Lomonosov Ridge in relation to Nordaustlandet

Little is known of the Lomonosov Ridge except that it is a markedly linear, non-magnetic submarine feature now bordering the Eurasian Ocean basin. This basin opened by Cenozoic spreading along the mid-oceanic Nansen Gakkel Ridge as the northerly terminus of the De Geer transform separating Svalbard from Greenland. The pre-Cenozoic configuration is constrained by simply closing the Eurasian and the Greenland and Norwegian basins. This brings the Lomonosov Ridge adjacent to the northern coasts of Svalbard and perpendicular to the widespread Caledonian grain of Svalbard. From its positive morphology and non-magnetic nature the Ridge would appear to be of continental rather than of oceanic affinity. Indeed such a relict 'orogen' could have focused the Cenozoic thermal fission, so determining the initial location of the NansenGakkel Ridge. That might be as far as speculation should be taken; but it may be worth considering this situation in relation to Nordaustlandet and to the mid-Paleozoic strike-slip model developed in this work. That model (e.g. Harland 1966, 1969) postulated the origin of the Lomonosov Ridge as a compressional feature that formed across the front of the eastern terranes of Svalbard as they progressed from the East Greenland province by strike-slip to

NORTHERN NORDAUSTLANDET their Carboniferous-Cretaceous location north of Greenland and Canada and so adjacent to where the Lomonosov Ridge is now. That northward progression could have been accomplished by the continental foreland of Svalbard's eastern province overriding the intervening Thalassic ocean. The subducted ocean floor would have sunk i.a. beneath northern Nordaustlandet and the ridge would develop from the scrapings of the ocean floor sediments. The above speculation is entered because the later phases of this translation would be Devonian and the later thermal rejuvenation along the E-W northern margin of Nordaustlandet from early radiometric determinations tend to be Devonian.

(3)

(4) (5)

(6)

Conclusion

(7) (8)

A model is suggested for further criticism and testing in which the following events in Nordaustlandet would be accommodated.

(9)

(1) (2)

Early to mid-Proterozoic sedimentation to form the Brennevinsfjorden Group. Early Neoproterozoic migmatism/magmatism (Grenvillian) Kapp Hansteen volcanics and Laponiahalvoya granites.

109

Later Neoproterozoic through Early Paleozoic sedimentation of the relatively unaltered Murchison Bay and Hinlopenstretet supergroups. Silurian (Ny Friesland) orogenic folding in NS axes with EW compression to transpression. Later Silurian through Devonian northward migration of Svalbard with subduction around North Greenland towards Ellesmere Island. Late Devonian accumulated thermal effects of subduction with Lomonosov orogen transverse to progression and hot fluids or magma from buried slab rejuvenating the E-W zone of Early Neoproterozoic granites etc. Late Paleozoic denudation and sedimentary cover. Renewed uplift in Late Cretaceous Cenozoic time as heat accumulated beneath northern Nordaustlandet and the Lomonosov Ridge leading to Spreading of the Eurasian Ocean Basin with the thermal tilting of the pre-Carboniferous basement so that northern Nordaustlandet exposes the deeper roots of the earlier structures whereas Late Paleozoic and Mesozoic platform strata obscure the basement further south.

Chapter 7 Northeastern Spitsbergen W. B R I A N 7.1 7.2 7.2.1 7.2.2 7.2.3 7.3 7.4 7.4.1 7.4.2 7.4.3 7.4.4 7.5 7.6 7.6.1 7.6.2 7.7 7.7.1 7.7.2

Geological frame, 110 Younger (cover) rocks, 112 Cenozoic lava, 112 Mesozoic dolerites, 112 Triassic to Carboniferous Strata, 112 Post-Permian deformation, 112 Ny Friesland plutons, 112 The Chydenius (breen) Batholith, 113 The Lomonosovfonna pluton, 113 Origin of magnos, 113 Lamprophyre dykes, 113 The Hecla Hoek Complex: the continuing debate, 113 Hinlopenstretet Supergroup, 116 Oslobreen Group, 116 Polarisbreen Group, 117 Lomfjorden Supergroup, 118 Akademikerbreen Group, 119 Veteranen Group, 119

The land (area) considered here is bounded on the west by Wijdefjorden and on the east by Hinlopenstretet and Storfjorden. The southern boundary is somewhat indefinite. For descriptive convenience Carboniferous through Triassic stratigraphy is treated in Chapters 4 and 5 and Devonian strata to the northwest in Chapter 8. It makes geological sense for these chapter areas to overlap where they meet. Ny Friesland was the name for most of the area under consideration. However, after the accession of the Norwegian King Olav V in 1957 his name was given to what had previously been a somewhat indefinite territory, mostly ice covered (the Terre Glac6e Russe of some older maps) to the south east of Ny Friesland. Olav V Land was defined to take in some of what had been referred to as Ny Friesland and early accounts should be read with this in mind (Miloslavskiy et al. 1993, map D8G). This chapter thus concerns Ny Friesland and north western Olav V Land and for descriptive economy Ny Friesland will be used for the area where most of the older rocks crop out. Much of the interior is covered by highland ice rather than an ice cap, meaning that the ice is not thick enough for the surface to be independent of the underlying relief. Indeed the ice cover is broken here and there by rocky cliffs of submerged valley glaciers. The three largest areas of continuous ice are Lomonosovfonna, Asg~rdfonna and Valhallfonna. The inland ice flows out along valley glaciers, often to the sea. In Olav V land the second largest glacier in Svalbard, Negribreen, meets the sea in a continuous ice cliff (Fig. 7.1). In addition there are independent valley and corrie glaciers. The two highest mountains in Svalbard (Newtontoppen 1717 m, and Perriertoppen 1712 m), each typically supporting a small ice cap, are not conspicuous in this highest mountainous region. An advantage of the area for geologists is the admirably clear rock surfaces in cliffs and glaciated pavements. When the Cambridge group began a systematic investigation of the geology of Ny Friesland there was no topographic base for most of the interior. Thus a combined survey was necessary in which the position of geological features was fixed by triangulation, thus producing a topographic map at the same time. The contours were plotted by a simple photogrammetric plotting table made for the purpose in Cambridge (Harland & Masson-Smith 1962). The main focus of Cambridge research until about 1965 concerned Ny Friesland, hence the balance of this Chapter may seem one-sided. The early work of Blomstrand (1864), Nathorst (1910), Tyrrell (1922), Odell (1927), Fairbairn (1933), Kulling (1934) and Fleming & Edmonds (1941) formed the basis of these investigations.

HARLAND 7.8 7.8.1 7.8.2 7.8.3 7.9 7.9.1 7.9.2 7.9.3 7.10

7.10.1 7.10.2 7.10.3 7.10.4 7.10.5 7.10.6

7.1

Stubendorffbreen Supergroup: succession, 121 Planetfjella Group, 121 Harkerbreen Group, 122 Finnlandveggen Group, 124 Stubendorffbreen Supergronp: genesis, 125 Petrology, 125 Geochemistry, 126 Isotopic ages, 127 The Hecla Hock Complex: mid-Paleozoic structure and metamorphism, 128 Fold and nappe structure, 128 Fabric and shear zones in the Stubendorffbreen Supergroup, 129 The Billefjorden Fault Zone, 129 Planett~ella schists, 129 Kinematic interpretation of transpressive shear in the Stubendorffbreen Supergroup, 130 Metamorphism, 131

Geological frame

The rocks divide naturally into three: older, younger and 'drift'. The older rocks comprise the Hecla Hoek complex and later batholiths. Unconformably overlying this are the cover strata: the northern extension of the Spitsbergen Basin sequence, being mainly Carboniferous and Permian with conformable softer Triassic rocks above. The youngest rocks are Q u a t e r n a r y - generally Late Quaternary glacial and marine beach deposits of trivial bulk. These three units are separated by two or three surfaces. (1) The older surface is the obvious unconformity which oversteps most of the older rocks. It is continuous in the south where it dips to sea level but occurs in Ny Friesland with small Carboniferous and Permian outliers. Indeed this is an unconformity with both overstep and some overlap. Originally a peneplane, it now emerges, with a southerly dip, from beneath the Central Basin and Eastern Platform to rise with an arched surface: enveloping the summits of the high mountains formed of the older rocks. Indeed Ny Friesland mounts the highest peaks in Svalbard. Towards the margins outliers of Carboniferous strata are perched on the flat unconformity at the mountain tops. More often the flat top is covered by ice or snow. Elsewhere the summits of sharp peaks fall within, or define, the smooth projected unconformity surface. (2) The younger surface is not so obvious because in the higher ground it is postulated to coincide with the older one, i.e. as an exhumed peneplane, or to truncate and cut down into it. It is indeed the present summit height envelope which encompasses all mountain tops whether of older or younger rocks. In this area it is demonstrably post-Triassic; further south it is at least post-Eocene. This is the surface that gives Svalbard a flat-topped appearance when seen from a distance and when the sharp peaks and steep cliffs are not evident. It represents the Late Cenozoic erosion surface that i.a. truncates the West Spitsbergen (Paleogene) Orogen. (3) The youngest surface is the most conspicuous being of latest Neogene or Quaternary dissection of the younger surface and is being actively formed today. It is the surface on which the youngest Quaternary deposits and glaciers rest so giving rise to the present day topography. Each of these surfaces represents a major diastrophic and erosional event. The older surface marks the Ny Friesland (Caledonian) Orogeny and its reduction to a peneplane. The younger surface marks the West Spitsbergen Orogeny and related tectogenesis in this area and its reduction again to a peneplane.

N O R T H E A S T E R N SPITSBERGEN

111

Fig. 7.1. Topographic and place name map of Ny Friesland. Based on Harland & Masson-Smith (1962). Spitsbergen, southern Ny Friesland 1 125 000, Royal Geographical Society and Geological Map of Svalbard 1:5000 000, sheet 3, Norsk Polarinstitutt.

112

CHAPTER 7

The youngest surface marks the relative uplift of that peneplane, in relation to sea level and its dissection to the distinctive relief seen today. The rock units are bounded by faults as well as by unconformities. Faults which displace the relatively flat-lying younger rocks are easy to map. They are demonstrably postPermian and probably belong to the Paleogene diastrophism as the eastern response of the West Spitsbergen Orogeny. Most faults within the older rocks did not continue to be active beyond the N y Friesland Orogeny. However, the Billefjorden Fault Zone (BFZ) was active in Paleozoic and Mesozoic as well as Cenozoic time. It bounds the Hecla Hoek rocks, faulting them against (Devonian) Old Red Sandstone to the west which is lacking in this sector and will be treated in the northwest sector (Chapter 8). The Lomfjorden Fault Zone is demonstrably post-Carboniferous; its earlier history is uncertain. It was certainly active during the Paleogene West Spitsbergen Orogeny. The main part of this chapter concerns the older rocks, i.e. the Hecla Hoek complex with its related intrusions (mainly the large late tectonic granite plutons). However, in conformity with this systematic descriptive approach the rocks are treated from the top down and the story interpreted from oldest to youngest follows in Part 3. This has the advantage of leaving the most difficult problems concerning the possibility and identity of a more ancient basement within the Hecla Hoek Complex till last. The youngest (Quaternary) rocks will not be treated here because there is little to distinguish their nature between the different sectors of Svalbard. Any generalizations belong to Chapters 21 and 22. The older rocks to the northeast pass without significant disconformity across Hinlopenstretet into the Hecla Hoek sequence of Nordaustlandet.

7.2

7.2.3

Sassendalen Group, 316 m (Mid- and Early Triassic). The Sassendalen Group strata mainly, shales and silstones, are as usual less resistent than the underlying Kapp Starostin Formation. The outcrop probably accounts for much of the low-lying ice covered area of Olav V Land and is discussed in Section 5.4. It is best known where it emerges southeast of Sassenfjorden in the type Sassendalen area as described in Chapter 4.4. The rocks are peripheral to the area considered in this chapter. The underlying three groups are also detailed mainly in Chapters 4 and 17 and the eastern outcrops in Chapter 5. Tempelfjorden Group, 381m (Late Permian). In many areas of Svalbard the Kapp Starostin Formation, a siliciclastic to cherty unit is a resistent marker of relatively uniform facies. Gipsdalen Group, 828+m (Early Permian and Pennsylvanian). The Gipsdalen Group of five formations is mainly formed of carbonates and evaporites. Facies vary markedly and are thicker in the Billefjorden Trough. The upper units extend westwards across the Billefjorden Fault Zone (BFZ) on the Nordfjorden High. The lower units thicken to the abrupt margin of the Fault Zone. It is noteworthy that the western margin of the older rocks of the Ny Friesland orogenic structure is also formed by the BFZ which continued active and controlled the western margin of the Carboniferous Billefjorden Trough. Billefjorden Group, 316m (Mississippian). The Billefjorden Group consists of two formations in the Billefjorden Trough. They are largely of continental sandstones with plant beds and some coal. Whereas these strata form the base of the cover or platform succession of the Central Basin (Chapter 4) they are preserved in a series of down-faulted outliers far to the north in western Ny Friesland just east of the BFZ. They may well have covered much of the older surface of western Ny Friesland before erosion. Differences are most evident in the lowest strata of the Billefjorden Group as seen in the map and section (from Cutbill, Henderson & Wright in Harland, Pickton & Wright 1976).

Younger (cover) rocks 7.3

7.2.1

Post-Permian deformation

Cenozoic lava

Teben'kov & Sirotkin (1990) reported the presence of a single small nunatak at the head of Manbreen, on the south side of Valhallfonna in eastern Ny Friesland, that consists of lava overlying Precambrian schists of the Planetfjella Group. The nunatak is only 10-30m high and is at an altitude of 800-820 m. The lower contact of the lava with the schist is subhorizontal. The lava is flaggy with subhorizontal joints and little internal structure; it was interpreted as a single lava flow. The lava is partly vesicular and scoriaceous, especially at the top, and contains phenocrysts, mainly of olivine, but also plagioclase and minor clinopyroxene. By analogy with the Woodfjorden plateau lavas, a mid-Miocene age was suggested, and it may once have covered the whole area. At the same time they rejected correlation with either the Mesozoic dolerites or the Quaternary trachy basalts from Bockfjorden. A non-oceanic magmatic source common with the Miocene lavas with TiO2-KzO-P202 ratios respectively 52.6-54.5%; 37.0 38.6%; 8.3 8.8%.

7.2.2

Triassic to Carboniferous strata

Mesozoic dolerite

A dolerite outcrop beneath the ice cap at Bivrastfonna, west of southern Lomfjorden, was included in the survey of dolerites by Tyrrell & Sandford (1993) and was mapped in more detail by Cutbill (1968) who showed it resting on sandstones of the Billefjorden Group. The ice cap is on a flat-topped mountain of truncated Veteranen Group Hecla Hoek strata and the dolerite is presumed intrusive into the overlying Carboniferous sandstones the upper contact of which is obscured if not removed by the ice. It must now be presumed to belong to the extensive Early Cretaceous magmatic event evident in many other outcrops east of Lomfjorden where black sills in Carboniferous and Permian strata are conspicuous in cliff sections.

The N-S Balliolbreen Fault is the main fault of the BFZ and it is seen best in the cliff north of Alandvatnet where a preCarboniferous reverse high-angle fault juxtaposes Old Red Sandstone on the footwall and metamorphic rocks of the Hecla Hoek complex on the hanging wall. This key exposure, first noted by Vogt in 1923 and later investigated by McWhae (1953) and by Harland in 1953 (1959), has been the subject of detailed structural mapping by Lamar, Reed & Douglass (1986) and Lamar & Douglass (1995). But as their area was predominantly of the Old Red Sandstone rocks, discussion of their work fits better into the following chapter in which the Billefjorden Fault Zone must be addressed from another point of view. In southwest Bfinsow Land not only are the strata folded in a compressive sense, but the upper gypsiferous strata are deformed penetratively so that original anhydrite 'spheres' have been sheared into westward-dipping elongated ellipsoids. The other main N - S fault that cuts the younger rocks is the Lomfjorden Fault, with its associated splays. This is perhaps the most conspicuous fault in the map of Ny Friesland though not so active as the BFZ in pre-Carboniferous time. It also concentrated Paleogene reworking of Mesozoic strata. The two fault zones are associated with normal dip-slip faults which, striking with the older structures, are only evident where the cover rocks are present.

7.4

Ny Friesland plutons

Pre-Carboniferous acid plutons intrude deformed Hecla Hoek strata. The boundaries are generally concealed beneath ice and Carboniferous cover, and so are mainly conjecture on the map except where the thermal aureole can be mapped. Three plutons have been identified, possibly the northern two are connected at depth.

NORTHEASTERN SPITSBERGEN

7.4.1

The Chydenius(breen) Batholith (Odell 1927; Harland 1959; Teben'kov et al. 1996)

This is the largest outcrop and is fairly well delineated by a thermal aureole superimposed on the regional metamorphic zones where the rocks are exposed. It forms the body of the highest mountain, Newtontoppen, which is mostly ice covered. The rock is a porphyritic granite with large rectangular pink orthoclase phenocrysts (not unlike Shap granite of England). The mineral composition from 40 samples ranged from adamellite to granodiorite (Harland 1959). This is typical of late tectonic plutons without noticeable foliation. Where marginal facies can be seen xenoliths and hybrid facies are evidence of stoping. The typical light-coloured coarser facies gave quartz 17%; potash feldspar (mostly microcline, often perthitic; the large phenocysts are typically orthoclase) 25%; plagioclase (oligoclase where determined) 11%; hornblende and occasional augite with associated chlorite 7%; titanite 0.6%; apatite 0.2%; zircon, allanite, muscovite, pyrite and ilmenite total about 0.25% (Harland 1959). It was from this pluton that early K Ar age determinations were made of a few samples, a small exposure on the flank of Newtontoppen at Eplet (Newton's apple). The values recorded by Gayer et al. (1966) are 385, 4 0 1 + 8 , 4024-8, 388+14; 406+15. Early to Mid-Devonian ages are suggested. A minor pluton occurs at Raudberget to the north of lower Chydeniusbreen and may have a subterranean connexion with the Newtontoppen granites. Teben'kov et al. (1996) in a historical introduction to their investigation omitted to mention the above work from the Cambridge reconnaissance which mapped and named most of the area topographically and geologically, the granite outcrops being virtually the same as the more detailed 1996map. They did, however, suggest a change in name to the 'Chydeniusbreen granitoid suite' to conform to the Norwegian Stratigraphic Committee and against the principal of priority and that names should be proposed according to official maps at the time. However, Teben'kov et al. described a more detailed survey of the individual outcrops, their structural features, with petrological and geochemical data. They described the following rock types: 1, melanosomes and dark grey granosyenites; 2, pink-grey granosyenite and pink quartz monzonite; 3, grey granite; 4, granosyenite with aligned K-feldspar phenocrysts; 5, aplitic veins; 6, pegmatites; 7, quartz-feldspar porhyry; 8, lamprophyre, their sequence of emplacement in that order. They concluded that the Newtontoppen granitoids are mainly granite and granosyenite intermediate between alkali-calcic and alkalic as between S and I-type granites. New Rb-Sr age determinations (Teben'kov et al. 1996) by whole-rock apatite isochron method gave 432 + 10 i.e. 30million years older than the earlier K - A r values which they interpreted as a cooling age. An Early Silurian age might challenge the Gee & Page (1994) Early to mid-Silurian age for the main metamorphism to the west, the granites being clearly intruded into already deformed strata as a batholith. Unfortunately the successive intrusive phases were not distinguished isotopically, and the innermost ?latest grey granites may not have been dated.

7.4.2

The Lomonosovfonna pluton

This is exposed only in the upper reaches of Nordenski61dbreen at Terrierfjellet, Ferrierfjellet and Ekkoknausane, but is projected to cover a large area beneath the ice field and so may qualify as a batholith. Evidence for its eastern subglacial extent is seen in granite boulders in the moraines of Tunabreen and Von Postbreen at the head of Sassenfjorden. From morainic specimens in Nordenski61dbreen, Tyrrell (1922) described pegmatites, quartz, veins and a syenitic suite. The syenite was confirmed in situ (Harland 1959). An unfoliated granite boulder from the moraine of Tunabreen at the head of Tempelfjorden yielded a Rb-Sr ?Late Silurian age of 421 + 11 (Gayer et al. 1966). Its most likely source

113

would be from a subglacial outcrop of the eastern extension beneath Lomonosovfonna of the Nordenski61dbreen Batholith. Teben'kov et al. (1996), without further work or reference to Tyrrell, referred to this as the Ekkoknausane group of small intrusives, more likely into the root of the batholith.

7.4.3

Origin of magmas

Harland (1971) suggested that shearing in the Silurian transpressive regime could have raised temperatures in the deeper Stubendorffbreen Supergroup rocks to generate granitic magmas. The Chydenius Batholith, especially, while marked by a thermal aureole extending horizontally to 1 km may have completed its diapiric emplacement in a relatively cool state so as to give the strength to shoulder away the near vertical N-S-striking strata and so causing significant attenuation. The thicknesses are locally reduced to about half. An ensialic origin is assumed. However, the early stages of intrusion truncated the Hecla Hoek strata.

7.4.4

Lamprophyre dykes

Some lamprophyre intrusions, long noted in Ny Friesland, and a monchiquite dyke by Teben'kov et al. (1996), but not investigated fully. They would appear to be related to the late phases of granitic intrusion. The lamprophyre dykes are unlikely be of the same suite as that at Krosspynten (monchiquite and camptonite), on the west side of BFZ, which are possibly of Bashkirian age (Gayer et al. 1966) and in another (allochthonous) terrane.

7.5

The Hecla Hoek Complex: the continuing debate

Hecla Hoek rocks are the core of Ny Friesland. The name, coined by Nordenski61d in 1863, comes from the mountain (now Heclahuken) named after Parry's ship H M S H e c l a that wintered at its foot in Sorgfjorden in 1827-8. Nordenski61d at first used the name for most of the rocks of Svalbard older than the (Carboniferous) Mountain Limestone. He included the ?strongly metamorphosed rocks, on the one hand, and the Old Red Sandstone on the other and all rocks of intermediate age. Nathorst (in Suess 1888) excluded the metamorphics as Archean and the Old Red Sandstone as the Liefde Bay System. His Hecla Hoek in Ny Friesland is equivalent to the upper two of the three supergroups earlier referred to as Upper, Middle and Lower Hecla Hoek. As already argued the use of the name Hecla Hoek for rocks west of the Billefjorden Fault Zone is not recommended. Many, however, still use it for any pre-Devonian rocks in Svalbard, seemingly on the assumption that all basement was Caledonian and then related spatially as now. A recurring question concerns the relationship between (a) the metamorphic rocks of western Ny Friesland i.e. Nathorst's Archean; Tyrrell's (1922) pre-Devonian basement complex; Fairbairn's (1933) 'western schists and gneisses' and (b) the relatively unmetamorphosed strata to the east regarded by all as Hecla Hoek. Such was a common problem in many Caledonian terranes in Europe, Greenland and North America. Three main options were under consideration: (i) that the western metamorphic rocks are basement i.e. much older than the eastern, being separated by a major diastrophic event; (ii) that the western rocks are older but pass relatively conformably up into the eastern; (iii) that the western rocks are the metamorphosed equivalents of the eastern. In both options (ii) and (iii) the age of metamorphism would be later than the age of the eastern rocks. These questions persisted as long as no comprehensive geological maps were available. Until 1955 no fossils had been found in Ny Friesland to give a clue as to the age of the eastern rocks. The problem was addressed over many years by the Cambridge group (from Fairbairn 1933; Harland 1941). This involved surveys:

114

CHAPTER 7

topographical (Harland 1952; Harland & Masson Smith 1962) as well as geological (e.g. Harland 1959; Harland et al. 1992). Annual expeditions from 1949 to 1964mostly by man-hauled sledges and small boats) involved many geologists especially: M. B. Bayly 1951, 1952, 1953; R. A. Gayer 1961, 1962, 1963; D. Gobbett 1958, 1959; W. B. Harland 1938, 1949, 1951, 1953, 1964, 1974, 1981, 1982; J. R. H. McWhae 1949; G. Vallence 1965, 1967; R. H. Wallis 1964, 1965, 1967; C. B. Wilson 1952, 1953, 1955, 1956, 1957. By 1955 the main problem seemed to be solved favouring the second option above: namely that a whole succession of strataabout 18km thick passed down from unmetamorphosed into metamorphosed strata and the age was Precambrian except for the top kilometre of strata which first revealed Early Cambrian S a l t e r e l l a r u g o s a to Wilson in 1955. The whole sequence was first published in outline (Harland & Wilson 1956) and revised with more information and international terminology (Harland, Wallis & Gayer 1966; Harland e t al. 1992) as shown in Figs 7.2 and 7.3. Further research enhanced the value of this succession, modified it, and is recounted in detail in Section 7.6-8. However, the succession as published was not at first challenged. Supporting evidence included: (a) the concordance of the main groups of rocks in similar sequence throughout Ny Friesland except for the lower units; (b) mapping of granitic gneisses as meta-sedimentary strata (volcanic or arkosic) within the succession, with some melting, remobilisation and minor intrusion; (c) the intense transpressive tectonism with bedding strike-slip juxtaposed higher and lower grades of metamorphosed rocks; (d) the chlorite zone boundary transgresses the stratigraphic boundary so that in the north even 'upper' Hecla Hoek rocks are so tectonized; (e) no major unconformity surface had then been identified though such might have been expected to be obscured within the intensely tectonized older rocks. On the other hand Harland (1941) described some of the rock units as nappes with attenuated lower limbs, i.e. thrust sheets. Moreover, Harland & Wilson (1956) admitted that the lowest units were so complex that they could well constitute a basement. It was also realised that with such intense shearing, discordant contacts could be smeared into concordance. It seemed unlikely that any major tectonism punctuated the succession above the lowest group. It was not thought that the overlying apparently regular and concordant sequence could contain a distinct orogenic episode. However, this tentative conclusion depended only on the rapid reconnaissance mapping of the whole area completed about 1965 which is inadequate in detail (e.g. Harland 1959; Harland et al. 1992). The above interpretation has been questioned and so it must be considered provisional. That is because a basement to the regular succession may be distinguished. Abakumov (1965) regarded the two lowest groups as basement, combining them in the Atomfjella Complex. D. G. Gee visited northern Ny Friesland with a view to collecting specimens to demonstrate by isotopic dating that there is indeed an ancient basement. For some time older Proterozoic dates had been rumoured (i.a Gee 1986) and the data when published (Gee et al. 1992) gave evidence for ages of granitoid rocks of 1700 1800Ma, said to be intruding sediments in the Harkerbreen Group. If the zircons analysed were not derived from an arkosic or igneous protolith it must be accepted that at least part of the Harkerbreen Group is Late Paleoproterozoic. Such an age by itself identified a tectonothermal event. But without accompanying structural stratigraphic evidence of a discontinuity in the sequence it need not represent an orogenic episode. This matter was developed by Gee e t al. (1992). One option thus appeared for a sequence without interruption back to at least 1800 Ma. This would not be impossible considering that a likely age for the oldest Veteranen Group rocks probably exceeded 800 Ma (Harland & Gayer 1972; Knoll & Swett 1985) and the underlying Planetfjella Group, first correlated with the Kapp Hansteen Group of Nordaustlandet, which appears to have consistent ages between 900 and 1000 Ma. G. M. Manby in an account (1990) used a structure radically different from that of Harland (1959). Applying an already agreed

Supergroup

Group

Formation

Member and character

Valhallfonna (220 m)

Profilbekken Olenidsletta

(S)

Z Kirtonryggen

(750 m)

S S n," S

S~ 8 Tokammane

(192 m)

Z

Dracoisen (245 m)

s

z

5

(N)

Nordporten Basissletta Spora

Upper Limestone Mbr i Middle Limestone Mbr! I Dolostone Mbr Lower Limestone Mbr

Didovtoppen Topiggane Bl~revbreen

Dolostone Shale Sandstone

Shales

Wilsonbreen (160 m)

6 members

Gropbreen (tillite) Member Middle carbonate Member Ormen (tillite) Member Slangen MacDonaldryggen

Dlostone Dolostones & siltstones

Petrovbreen

1111ite

Elbobreen

(362 rn)

Age Llanvirn Late Arenig

Arenig mremadoc-Arenig mremadoc

Early C a m b r i a n

? Ediacara Late V a r a n g e r

Early V a r a n g e r

Lower carbonate Member Mainly limestone Upper dolostone Backlundtoppen

wZ

Shale Middle dolostone Oolitic limestone

(360-700 m)

U.I~ n" E ~oo v ~ .~ o I~ ~ ~v

Draken (25-300 m) Upper limestone Stromatolitic dolostone Lower limestone Lower dolostone

Svanbergfjellet

(100~625m)

'~

Upper (pale) Member

6 limestone beds

Lower (dark) Member

4 limestone & dolostoee beds

Grusdievbreen (865 m)

Oxfordbreen (550 m)

Fulmarberget shale Enpiggen Upper Greywacke Upper Quartzite Lower Greywacke Lower Quartzite

Glasgowbreen

ilZl•

(540 m)

o

Kingbreen (-1500 m)

>

Cavendishryggen -J-- Rheaninden Beds Quartzite L _ Bl&rinterBeds BogenLimestone 6 divisions Galoistoppen 2 divisions

Kortbreen (1200 m) Vildadalen

(3250 m)

E i o ' O._o v.=_ 8_

Fl&en (1500 m)

Sturtian

Sturtian

Late R i p h e a n

Quartzite Member Limestone Member Ros~nflella (=Eosletta skam zone Manby & Lybeds) Albreen Alryggen T~breen upper Member Middle Member Lower Member

[? 950 Ma]

Sorbreen

(250 m)

o

x

Vassfaret (600 m)

zI.U

Bangenhuk

LLI~

~IT

g

Lower Member

(2000 m)

Femmilsjoen Flatoyrdalen

Rittervatnet

Amphibolites, feldspathites and psammites, with metatillites at the top

Feldspathic bodies

z

Upper Member Middle Member

(350 m)

[c.1750

Ma] (I) (3)

Psammitic pelites with graphite Marble and quartzite

P o l h e m (2000 m) incl. near basal Inastadse~lga conglomerate ' "lnstrumentberget

(5)

.1_

--

-

Granitic gneiss

Smutsbreen

Westbyf]ellet Bohryggen

,~t-e,l v

Ingstadseggaconglomerate

Fl&tan (3)

[< 131 7 Ma] (8) [C.1750

Ma] (3)

[<1190 Ma] (7)

Einsteinfjellet

Eskolabreen

LemstrOm~ellet Malmgrent]ellet

[c. 1750 Ma] (4) [? 2145 Ma] (2)

Sederholm~ellet

Fig. "/.2. Summary of the Hecla Hoek succession of Ny Friesland, based on Harland & Wilson (1956), Harland & Wilson (1966) and Harland et al. (1992), with numerical ages from (1) Gee et al. (1992); (2) Balashov et al. (1993); (3) Johansson et al. (1995); and (4) Larionov et al. (1995). The value of 950 Ma is by suggested correlation with Nordaustlandet; unit (5) introduced by Abakumov (1965); (6) Johansson et al. (1995). The diagram shows the units in their sequence and classification; (7) Gee & Hellman (1997); (8) Hellman et al. (1997).

NORTHEASTERN SPITSBERGEN

115

strike-slip zone within the Planetfjella Group he argued for a major tectonic event between the 'middle' and 'lower' Hecla Hoek, thus going back to option (i) above i.e. in which the basement is the whole Sturbendorffbreen Supergroup. This argument was countered (Harland et al. 1992) then resuscitated (Gee & Page 1995; Manby & Lyberis 1995) and again countered (Harland 1995) on the basis that the only systematic mapping yet done shows a conformable sequence, though admittedly highly sheared (Wilson 1958; Wallis 1969). It was again rejuvenated (Witt-Nilsson, Gee & Hellman 1997). However, Harland (1997) while confirming the concordance and indeed conformable relationship between the Veteranen and Planetfjella groups, noted two lines of evidence for an unconformity between the Planetfjella and Harkerbreen groups. This could mark the hiatus between the two groups but not sufficient to warrant a major orogenic episode, the older strata even though intruded and thrust still mapped out in a fairly consistent sequence. There is as yet no sufficient case to abandon the original description of this remarkable sequence. A further matter concerns the presence of basic igneous material. It is virtually absent from the upper two supergroups and the upper (Planetfjella Group) of the three groups in the lower Supergroup. The middle (Harkerbreen) Group is rich in amphibolite which had mostly been interpreted as volcanic lavas and tufts with some intrusions. The lower group comprises two formations. The upper (Smutsbreen) formation has almost no basic rocks and the lower (Eskolabreen) formation has both acid and basic gneisses and has always been a serious candidate for ancient basement. The question arises that if the Harkerbreen feldspathic rocks were mainly intrusive instead of pyroclastic then it would pose a problem for the underlying Smutsbreen Formation to have escaped conspicuous intrusion if they were originally beneath. There have been still older ages rumoured in the oldest complex which all along has been suspected as basement (Balashov et al. 1993). However, in spite of announcing a much older zircon date they found the sequence to be concordant. Then Larionov et al. (1995) found c. 1770 Ma zircons in these older rocks also uniting the oldest group with the Harkerbreen Group in Abakumov's Atomfjella Complex. Johansson, Gee et al. (1995) reported good isotopic ages (1720 and 1770 Ma) from zircons from granitic bodies at two levels in the Harkerbreen group in northern Ny Friesland. Larionov, Johansson et al. (1995) reported similar (c. 1750 Ma) ages in the lowest group of the Atomfjella complex. The consistency of these results then appeared to establish the Atomfjella Complex as late Paleoproterozoic with a probable gap up to 800 Ma before Planetfjella schists were formed. New data, kindly made available in advance of publication, throw new light on the problem. Gee & Hellman (1997) determined detrital zircon crystal ages by the zircon-lead evaporation method, which gave a wide span of ages from the metasedimentary Smutsbreen Formation, so indicating the original sources of sediments. The youngest two zircons ( l l 9 0 M a ) gave the maximum age for sedimentation. Similarly, Hellman et al. (1997) gave a maximum age of 1317 + 7 Ma for the Polhem Formation quartzites. Witt-Nilsson, Gee & Hellman (1997) using the above data added detail of the Polhem basal conglomerate, with a reinterpretation of the Atomfjella Antiform with consequent stratigraphic adjustments. The interpretation of all the above data may now be reviewed again. (a) First giving primary reference to stratigraphic-structural observations, the following may now be taken as established.

Fig. 7.3. Generalized geological map of Ny Friesland outlining the distribution and subdivision of the Hecla Hoek Complex (adapted with permission of Cambridge University Press from Harland et al. 1992 and Johansson et al. 1995).

(i) All authors from Harland (1941) onwards recognized that the Caledonian deformation involved significant thrusting and nappe formation and, with one exception (Manby 1990; Manby & Lyberis 1995), agree with westerly vergence. (ii) There is general agreement that the intense sinistral Caledonian shear (transpression of Harland 1971) affects the whole structure west of the Veteranen Line.

116

CHAPTER 7

(iii) The Veteranen Line is the boundary between the overlying Veteranen Group and the Planetfjella Group and has been taken as a conformable sequence (Harland & Wilson 1956; Wilson 1958; Harland, Wallis & Gayer 1966; Wallis 1969) on the basis of field observations. Others who have opposed this conclusion have not contradicted the field evidence, but rather argued in support of their speculative terrane boundary. Though admittedly faulted, the succession is taken here as first proposed. (iv) An unconformity, above the Harkerbreen Group must be assumed on the basis of Abakumov's unpublished map showing successive formations of the Harkerbreen Group wedging out northwards against the overstepping and overthrust Planetfjella Group, and the comparison of the Harkerbreen successions from south to north as plotted by Johansson e t al. (1995) and pointed out ( H a r l a n d 1996). (v) An unconformity beneath the Polhem Formation where it rests on the newly established Instrumentberget-Fl5tan granitoid rock with basal conglomerate including granitoids of the same age (Johansson et al. 1995; Helhnan et al. 1997). (vi) Witt-Nilsson, Gee & Hellman (1997) named four nappe units each resting on a thrust of the nappe name. According to (iii) above the uppermost nappe is an integral part of the whole succession above the Harkerbreen Group. Moreover, the four main metasedimentary Harkerbreen formations appear in the succession in the same sequence as originally listed. It might appear that the Caledonian nappes have not significantly disturbed the original stratal sequence. It does, however, show that the Planetfjella Group is thrust over the lower metasedimentary (Polhem) formation of the Harkerbreen Group. (vii) Witt-Nilsson et al. (1997) showed that the Atomfjella Antiform continues from south to north of Ny Friesland and that the northern axis is displaced 3.5km eastwards from the position suggested by Gayer (1969), which simplifies the correlations in the succession and by introducing the Instrumentberget-Flfttan granitoid unit. They found beneath the Polhem Formation and to the north beneath the Instrumentberget granitoid, in the extreme north and in the axis of the antiform, rocks which match the Smutsbreen Formation. This suggests continuity of the relationship between the Harkerbreen and underlying Finnlandveggen groups through a distance of 130 km. (b) To the above field observations the following isotopic age w o r k m a y be s u m m a r i z e d thus. (i) The Caledonian age of the main deformation and metamorphism is confirmed as Silurian (Gayer et al. 1966; Gee & Page 1994). (ii) All the principal granitoid/feldspathite units gave zircon ages clustered around 1750 Ma. (iii) The only two (lowest) sedimentary formations so far investigated suggest that they could not have been formed earlier than 1100 or 1300 Ma (Gee & Hellman 1997; Hellman et al. 1997). (c) F o r interpretation of the above at this early stage only two hypotheses a p p e a r to survive and others m a y well be needed. (i) The granitoids (feldspathites) with consistent zircon ages of about 1750 Ma were at first confidently asserted as intrusive granites into older sedimentary formations (Gee et al. 1992; Johansson et al. 1995), but now the sedimentary units appear to be younger. Witt-Nilsson, Gee & Hellman (1997) and Gee (1996) reinterpreted the granitoids as being basement to the metasediments. Thus each nappe unit comprises granitoid basement beneath a different formation and stacked so as to give the originally recorded stratigraphic sequence, and as mapped by Abakumov to the east. (ii) The original conception based on the appearance of the granitoids/ feldspathites being concordant within the stated succession and so being metavolcanics need not yet be superceded. This explanation would fit the idea of an original stratal sequence, but now with two minor unconformities, whch did not unduly disturb the succession downwards without any major orogenic break. The difficulty with this is to account for the consistent c. 1750 Ma zircon ages of the geochemically cogenetic feldspathites. It just might be that an older granite of that age, say to the north of Ny Friesland, was melted and produced a succession of rhyolites and ignimbrites within the stratal succession. Under intense Caledonian metamorphism, gneisses or even granitoids would be formed, with some mobilization and intrusive contacts. This would account for the 'plutonic' zircons. This p r o b l e m has occupied the a u t h o r off a n d on since field w o r k in 1938 a n d he hopes to survive to learn the answer.

7.6

Hinlopenstretet Supergroup

H i n l o p e n s t r e t e t Supergroup, 1 . 9 k m ( H a r l a n d e t al. 1966; ' u p p e r H e c l a H o e k ' of H a r l a n d & Wilson 1956; H a r l a n d 1960, 1961, 1965). The S u p e r g r o u p crops out t h r o u g h o u t eastern N y Friesland and n o r t h w e s t e r n Olav V L a n d and in n o r t h w e s t e r n N o r d a u s t l a n det. It comprises two groups.

7.6.1 OslobreenGroup ( H a r l a n d & Wilson 1956; G o b b e t t & Wilson 1960) The Oslobreen G r o u p comprises a distinctive Early C a m b r i a n a n d Early to m i d - O r d o v i c i a n (Llanvirn) succession. It is d o m i n a t e d by c a r b o n a t e s of shallow m a r i n e facies. There are seemingly b a r r e n dolostone strata where Mid- and Late C a m b r i a n strata might be expected. The Oslobreen Series was first described in six units from central N y Friesland ( H a r l a n d & Wilson 1956; G o b b e t t & Wilson 1960). (6) (5) (4) (3) (2) (1)

U p p e r Oslobreen Limestone, 500 m M i d d l e Oslobreen Limestone, 220 m K i r t o n r y g g e n Dolomite, 85 m L o w e r Oslobreen Limestone, 160m Oslobreen Dolomite, 200 m Oslobreen Sandstone, 4 5 m

Wilson h a d discovered the first fossils in the N y Friesland Hecla H o e k strata with the Early C a m b r i a n S a l t e r e l l a r u g o s a in units (1) and (2). W h e n H a r l a n d , Wallis & G a y e r (1966) retermed the succession as the Oslobreen G r o u p with two formations, the K i r t o n r y g g e n F o r m a t i o n comprised units (6) to (3) and units (2) and (1) became the T o k a m m a n e F o r m a t i o n . H i g h e r strata were later discovered and n a m e d the Valhallfonna F o r m a t i o n above the K i r t o n r y g g e n F o r m a t i o n and the m o r e complete succession in northeast N y Friesland became the better standard (Fortey & Bruton 1973). The three formations are thus: Valhallfonna F o r m a t i o n (Mid-Ordovician) K i r t o n r y g g e n F o r m a t i o n (Early Ordovician) T o k a m m a n e F o r m a t i o n (Early C a m b r i a n ) Valhallfonna Formation, 220 m (Llanvirn limestones). The formation was set up after discovery on the north eastern coast of Ny Friesland and exposed in the cliffs along Hinlopenstretet of richly fossiliferous strata by CSE in 1965 (Vallance & Fortey 1968). It was described systematically by Fortey & Bruton (1973). The marine fauna has been only partially described, especially its trilobites and graptolites, from collections made first by CSE and later by the Natural History Museum, London and Palaeontological Museums, University of Oslo. From these the following work has arisen making this Llanvirn fauna one of the richest in the world. Whittington 1968, Fortey 1971, 1974a, b, 1975a, b, 1976, 1980; Fortey & Holdsworth 1971; Archer & Fortey 1974; Bockelie & Fortey 1976; Bockelie & Yochlson 1976, 1979; Fortey & Barnes 1976, 1977; Fortey & Whittaker 1976; Morris & Fortey 1976; Bockelie, Bruton & Fortey 1977; Fortey & Morris 1978; Cooper & Fortey 1977; Bockelie 1980; Cooper & Fortey 1982; Peel & Smith 1988; Bergstrom 1989; Smith, Sonderhom & Tull 1989; Cooper & Lindolm 1990). The Valhallfonna Formation was named from the ice cap, to the northeast of which the rocks are exposed along the coast. It was divided into two members as described by Fortey & Bruton (1973). Profilbekken Mbr, l l0m, is of massive limestone beds at the top grading downwards into well-bedded grey limestone strata. The top 5 m comprises grey-green shale. These softer beds may be the level at which higher strata were eroded away. The lower 5 m include beds transitional with the top of the underlying member faunally and lithologically. The base is taken at the occurrence of inarticulate brachiopods and phosphatised trilobites. The member contains an abundant fauna, mainly trilobites, representing at least 13 families and correlated with the middle Table Head Formation of Newfoundland i.e. White Rock Stage of mid- Ordovician age (Llanvirn). Olenidsletta Mbr, 145 m, of black and grey limestones and shales. The uppermost 43 m are of black limestone and shale 27 m of alternating black and grey

NORTHEASTERN SPITSBERGEN crystalline limestone beds. The lower 75 m are of black limestone and shale with an olenid trilobite fauna and a rich earliest Arening graptolite fauna. Kirtonryggen Formation (Harland, Wallis & Gayer 1966). The locality and the formation are named for John Kirton, an undergraduate of Queens College, Cambridge, who lost his life in 1958 on the mountain while collecting Early Ordovician fossils from this newly discovered locality (Harland & Wilson 1956; Harland 1958). His companion subsequently continued the study (Gobbett 1960; Gobbett & Wilson 1960). Four units (members) were described in this part of central Ny Friesland: at the type section in Kirtonryggen. (4) Upper (Oslobreen) Limestone Unit, 500+m, is formed of massive monotonous limestones with partial dolomitization giving a mottled appearance. The lower 200 m is fossiliferous. (3) Middle (Oslobreen) Limestone Unit, 200 m, of massive grey-brown cragforming limestone interbedded every 1-5 m with knobbly flags. It is often recrystallized shelly or oolitic limestone, with fecal pellets and algal nodules with Girvanella and trace fossils. Fossiliferous horizons yielded brachiopods and many trilobite species of Mid- to Late Canadian age. (2) (Kirtonryggen) Dolostone Unit, 70m, close-jointed, yellow-weathering dolomite siltstone interbedded with grey-brown porcellanous limestone, often partly silicified. (1) Lower (Oslobreen) Limestone Unit, 114 m on Kirtonryggen, up to 160 m north of Oslobreen is characterized by three main lithologic facies: (a) 'Knobbly flags', (b) massive fine-grained limestones with veins of white calcite, shell fragments faecal pellets and some stromatolites; (c) partly dolomitized limstones with pink to red patches and beds. Three fossil horizons occur in flaggy limestones in the middle of the unit with an early rugose coral, new species of trilobite Hystricurum wilsoni, the fauna being of Early Canadian age. Its base is marked by a sharp contact with the underlying dolostones. The above four units were named as divisions (members) of the Kirtonryggen Formation (Harland, Wallis & Gayer 1966). In northern Ny Friesland, north of the type locality, but below the Valhallfonna :Formation succession, Fortey & Bruton (1973) described the Kirtonryggen Formation with three members as follows: Nordporteu Mbr, 220 m, is entirely of limestone. The upper, 145m, is of light grey or brown massive limestone with thin bedded limestone intervals often stained black with stylolite surfaces and calcite veining often with hematite staining. The middle, 65m, of massive grey fossiliferous limestone with shaly interbeds The basal, 10 m, is of massive resistant limestone forming a headland. Detailed correlation has not been attempted, but it would appear that the Nordporten Member corresponds with the middle and upper (Oslobreen) Limestones of Central Ny Friesland (units 3 & 4 above). Basissletta Mbr, 250 m, of alternating dolostone or dolomitic limestone to limestone with a variety of facies. The upper 100+ m is only accessible with difficulty at low tide (in which about 40 m are not seen) is of micritic limestones with sparite and oosparite 2 m units, and shales. 50 m is of porcellanous dolostone often pale brown to black interbedded with dolomitic shale, with a variety of distinctive beds. 60 m is of alternating yellow weathering dolostone and grey limestone with stromatolitic horizons, oncolites and intraformational conglomerates. The lower 40 m is of cavernous bright yellow-weathering dolostone. The Basissletta Mbr correlates with the dolostone unit (2) above. Spora Mbr, 20 m, of fossiliferous massive limestone with some dolomite and hematite staining. The trilobite fauna is of Early Canadian age and correlates with unit (1) above. As generally applies in the north Atlantic region (northwest Scotland, East Greenland and Svalbard) Late and Mid-Cambrian faunas are missing and the dolostones between Arenig and Siberian are relatively barren. Swett (1981) noted that Early Ordovician conodonts are found only 160m above the Tokammane Formation so that late and mid-Cambrian time is either represented by the 100 200 m of seemingly barren strata and/ or by a significant time gap at the sharp lithological boundary change between the formations. Recent lower numerical estimates of the age of the Early Cambrian boundaries may reduce significantly the duration of Late and Mid-Cambrian time and hence the scale of the problem. Tokammane Formation. Wilson found cf. Salterella rugosa, (Billings) identified by C. Poulsen, the first Hecla Hoek fossil record in Ny Friesland (Harland & Wilson 1956) and the strata were established as Early Cambrian (Cowie 1974; Harland, Perkins & Smith 1988; Smith 1988). The lower two of the six Oslobreen units originally described were included in this named formation by Harland, Wallis & Gayer (1966).

117

Sedimentological studies followed (Swett 1981; Swett & Crowder 1982; Kidder & Swett 1989) and led to three members being established in Central Ny Friesland: (Swett 1981): The Ditlovtoppen Dolostone Member combines the upper and lower dolostone divisions of Harland & Wilson (1956) and Harland et al. (1966). The Topiggane Shale Member and The Blfirevbreen Sandstone Member is the sandstone division/member in the same two papers. Further palaeontological work was reported (Lauritzen & Yochelson 1982; Knoll & Swett 1987). In northeastern Ny Friesland Fortey & Bruton (1973) described the Tokammane Formation but without division into members. Tokammane Fm, in Central Ny Friesland Ditlovtoppen (dolostone) Mbr, 217 m, (descriptions from Swett 1981) The type section is composite from nunataks at Topiggane, Tokammane and Kirtonryggen. They are correlated on the basis of a Salterella-rich horizon 120m above the base of the member. The upper beds are medium crystalline dolostones weathering medium grey to greyish green with some mottling and stromatolitic structures. Some pebble-flake horizons are imbricated edgewise. Elongate nodules of coarsely crystalline cherts occur near the top of the formation. These may be evidence of former evaporites. Trace fossils (Planolites) occur. The top of the member is clearly distinguished by an abrupt change to the Kirtonryggen Limestone Formation. Salterella occurs in the middle and the top of the dolostone member making the whole of the Tokammane Formation no younger than Early Cambrian. Topiggane (shale) Mbr, 27 m, comprises green (glauconitic) to grey shales interbedded with thin, brownish weathering, glauconitic, phosphatic, and dolomitic sandstones. The unit forms a distinctive saddle between the more resistent members between which it lies. Swett (1981) distinguished this shale member because of its anomalous potash concentration which appeared to match that in the 'Fucoid Beds' of northwest Scotland and similar horizons in East Greenland and Newfoundland. It thus appears to be part of a widely distributed facies representing the weathering products of either volcanic sources or displacement of potash from illitic clays during dolomitization. The wide distribution may favour a cratonic weathering diagenetic origin rather than a volcanic source for which there is no other evidence at this time (Swett 1981). The potassium occurs as finely crystalline authigenic K-felspar (adularia). Kidder & Swett (1989) reported research that the phosphatic clasts in the Topiggane Member are of at least two kinds. Some resulted from diagenetic alteration of glauconite. Some pebbles were reworked concretions. The concretions may have been primary phosphatic deposits characteristic of earliest Cambrian sedimentation throughout the world as a result of oceanic upwelling at a continental shelf. However, in Spitsbergen the deposits are minor and formed apparently in a shallow shelf setting. Salterella occurs in the shale in Central Ny Friesland as well as in the overlying dolostones so indicating an early Cambrian age (Gobbett & Wilson 1960). Salterella has been regarded as belonging to the North American province. In the north an olenellid fragment was found 32 m from the base of the formation in strata probably equivalent to this shale member or to the dolostone member above. No correlation with Central Ny Friesland was attempted by Fortey & Bruton (1973), but their sequence was similar. Bl~revbreen (sandstone) Member, 33 m at south Tokammane appears to thin northwards. The sandstones are typically quartz arenites with 99+% quartz in medium to fine grain sizes and compacted with sutured interpenetration of quartz grains which, with acicular rutile inclusions, indicate a plutonic source. Occasional glauconite grains indicate a marine origin as do trace fossils especially in the north. Current laminations are typically planar. An Early Cambrian age is indicated by trace fossils Diplocraterion, Monocraterion and Scolithus in the northern exposures (Fortey & Bruton 1973) and confirmed by the occurrence of Salterella immediately above the sandstone member.

7.6.2

Polarisbreen Group ( H a r l a n d & Wilson 1956)

The Polarisbreen Group is d o m i n a n t l y o f shales with two tillite horizons o f w h i c h the u p p e r is the m o s t distinctive having exotic in a d d i t i o n to intrabasinal stones. T h e tillites in ' G o r g e Valley' in n o r t h N y Friesland were first identified by F l e m i n g & E d m o n d s

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(1941). Tillites were identified elsewhere in central-eastern N y F r i e s l a n d a n d the n a m e P o l a r i s b r e e n Series was i n t r o d u c e d by H a r l a n d & W i l s o n (1956). T h e P o l a r i s b r e e n G r o u p o f three f o r m a t i o n s : D r a k o i s e n , W i l s o n b r e e n a n d E l b o b r e e n was f o r m a l i z e d by H a r l a n d , Wallis & G a y e r (1966), the m i d d l e f o r m a t i o n being c h a r a c t e r i z e d by the c o n s i p i c o u s tillite: A t t h a t t i m e the o p i n i o n t h a t such tilloids were glacigenic deposits was being c h a l l e n g e d (e.g. K l i t i n 1960, 1964, 1965; C r o w e l l 1964; K r a s i l ' s h c h i k o v 1967; S c h e r m e r h o r n 1974), b u t also s u p p o r t e d ( H a r l a n d 1964; H a r l a n d , H e r o d & Kinsley 1966; H a r l a n d & H e r o d 1975). F u r t h e r C S E fieldwork in 1981 a n d 1982 established the earlier tillite w i t h i n the E l b o b r e e n F o r m a t i o n a n d elsewhere ( H a m b r e y 1982, 1983; F a i r c h i l d & H a m b r e y 1984). O n e o f the genetic p r o b l e m s was the a b u n d a n c e o f c a r b o n a t e s associated w i t h these glacial deposits. It was a d d r e s s e d by isotopic investigations (Fairchild et al. 1989; F a i r c h i l d & Spiro 1987, 1990) a n d a cold w a t e r e n v i r o n m e n t was c o n f i r m e d . A c o m p e h e n s i v e d e s c r i p t i o n o f V e n d i a n strata t h r o u g h o u t S v a l b a r d ( H a r l a n d , H a m b r e y & W a d d a m s 1993) i n c l u d e d a definitive a c c o u n t o f these strata in S v a l b a r d w h i c h is the source o f the following detail. Dracoisen Formation, 525 m, is the upper Polarisbreen Shale of Harland & Wilson. Although no disconformity has been noted at the top, micropalaeontological studies suggest a depositional hiatus spanning the time interval equivalent to the Late Ediacara and early Siberian beds of Eastern Europe (Vidal & Knoll 1982; Knoll & Swett 1987, 1990). Microfossils include Bavinella faveolata, Protosphaeridium sp., thin-walled leiosphaerids and rare acritarchs, which collectively indicate a Vendian age. As the underlying member is probably of Late Varanger age it is reasonable to suggest an Ediacara age for the Dracoisen Formation. The formation reflects a dominantly marine lacustrine environment following abruptly the glacial conditions of the underlying Wilsonbreen Formation. The uppermost of the six members show evidence of drying out and evaporitic minerals: anhydrite/gypsum and halite (Hambrey 1982). (D6) Upper Dolomitie Shale Sandstone Mbr, 150 m, the upper contact is obscured. The member is of a fine-grained dolomitic green sandstone interbedded with highly dolomitic maroon mudstone. Mudstone layers show evidence of atmopheric exposure with desiccation structures and rain pits. Small nodules appear to have originated as anhydrite or gypsum crystals. (D5) Middle Dolostone Mbr, 10m, is of pure cream-weathering, grey laminated dolostone and minor limestone; similarly with desiccation cracks and evaporite pseudomorphs. (D4) Middle Dolomitic Shale Sandstone Mbr, 150 m, is of finely laminated, fissile black, dark-grey and brown-weathering shale. Is not dolomitic and not well exposed. The lower contact is not exposed. (D3) Black Paper Shale Mbr, 150m, is of finely laminated, fissile black-, dark grey-, brown-weathering shale. It is not dolomitic and not well exposed. The lower contact is not exposed. (D2) Impure Carbonate Mbr, 105m, shaly dolostone and limestone with uniform parallel lamination. (DI) Basal Dolostone Mbr, 20m, was the 'third pale band' of Wilson & Harland (1964) and transferred to the Dracoisen Formation (Hambrey 1982). The member is of maroon laminated fissile dolostone, the laminations defined by variation in organic matter, silt or cement content. There is a sharp channelled contact at the base with the underlying formation. Wilsonbreen Formation, 160-170 m, is the Polarisbreen Tillite of Harland & Wilson (1956), Wilson & Harland (1964). It is the principal diamictite in the Polarisbreen Group. Two tillite members are separated by the Middle Carbonate Member (Fairchild et al. 1989) and display ungraded rhythmites alternating sand and carbonate laminae with stromatolites and brecciation related to anhydrite/gypsum relicts. The thickness of the formation is constant over a distance of 55km but the thickness of the individual members varies. The two tilloid members (Gropbreen and Ormen) are rich in both intrabasinal clasts (of underlying Hecla Hoek strata) and up to one third of extra-basinal igneous and metamorphic stones of unknown provenance. Of these, red granites and pink grey gneisses are the most common. The tilloid units have been the subject of detailed investigation, establishing by many features and beyond doubt their glacial origin. The first glacial material was water-lain; striated carbonate stones are common. Ice sheet conditions with transport of subglacial moraine was the major process with intermittent glaciomarine conditions indicated by dropstones. A striated cobble pavement

at Ditlovtoppen and preferred orientation of stones suggested movement from the southeast (Chumakov 1968, 1978; Fairchild & Hambrey 1984). The diamictites rest on pale dolostones with evidence of periglacial environment the isotopic evidence is of a cold water environment. Wilsonbreen Fm (W3) Gropbreen Mbr, 73m, is a diamictite with minor sandstone and siltstone. (W2) Middle Carbonate Mbr, 3-10 m, is a limestone of ungraded rhythmites alternating sands and carbonate laminae with stromatolites. Some distortion and brecciation suggest collapse from evaporite disolution of anhydrite and gypsum. Fairchild et al. (1989) reported oxygen and carbon isotopic studies which concluded that glaciation extended to low latitudes. (W1) Ormen Member, 85 m, is similar to (W3) but has a minor breccia. The top is sharp and there is top of a basal conglomerate on the underlying formation which was already indurated and with frost wedges indicating subaerial exposure. Elbobreen Formation was the Lower Polarisbreen Shales of Wilson & Harland (1964) and was so named by Harland et al. 1966. It was redefined and divided into four members including a further diamictite the Petrovbreen (E2) Member (dolomitic) by Hambrey (1982) and Fairchild & Hambrey (1984). (E4) Slangen Mbr, 14-28 m, is the 'first pale band' of Wilson & Harland (1964) is of cream or white-weathering dolostone and comprises three distinct divisions (Fairchild & Hambrey 1984). The upper division (unit C) is of sub-millimetre laminae of silt and dolomicrite, locally peloidal, oolitic or intraclastic, and stylolitic. The middle division (unit B) is of oolitic dolostones The lower division (unit A) is of well-sorted dolo-arenites with cherts and quartz probably after calcium sulphate. The base is transitional. (E3) MaeDonaldryggen Mbr, 145m, grey, laminated, shaly-muddy dolostones with siltstones and pure dolostones. (E2) Petrovbreen Mbr, 2+ to 42 m, a highly dolomitic diamictite, wacke and mud rock, variable in thickness with a sharp base, sandstones and clayey siltstones. The whole clast content may be matched with the underlying member except for rare volcanic fragments and black limestones. The stones are often striated and flatiron shaped, similar in many respects to those of the Wilsonbreen tillites except for a lack of conspicuous extra-basinal clasts. The unit was described in detail by Fairchild & Hambrey (1984) and environmental conclusions were again summarized by Harland, Hambrey & Waddams (1983) and discussed here in Chapter 13. (El) Lower Carbonate Mbr, 180m, is dominated by bluish black or grey limestone. It was redefined by Hambrey & Fairchild (1984) from the Lower Limestone Member of Hambrey (1982) by including dolostones and sandstones directly beneath the Petrovbreen Member. The upper division, 27m, is represented by pale yellow-weathering stromatolitic dolostone with bioherms up to 3 m (the largest being 10 to 50 m diameter and up to 6 m high) and spaced at 30 to 60 m. Grey dolomitic shales of E2 pass down into dropstone-bearing strata. Anhydrite-bearing silicified dolostones are also common and some rare cherts occur. This division passes down into Quartz arenites, 5 m, with subordinate shale and shaly limestone. Below this division is the main bulk of the member (El) which typically is of uniform bluish grey to black limestone with calcite veining from later deformation. The Polarisbreen Group is thus characterized by the upper (Dracoisen) formation, probably of Later Vendian (Ediacara) age. The middle (Wilsonbreen) formation is certainly of late Varanger age (Mortensnes Stage) and the lower (Elbobreen) formation is of early Varanger age (Sm~lfjord Stage) both early Vendian. It represents a siliciclastic interlude of cold and glacial conditions between the carbonate groups above and below, which formed in warmer environments.

7.7

Lomfjorden Supergroup

(Harland,

Wallis & Gayer

1966)

T h i s is the m i d d l e Hecla H o e k , c. 6 k m , o f H a r l a n d & Wilson (1956). It c o m p r i s e s two g r o u p s (series): A k a d e m i k e r b r e e n a n d V e t e r a n e n , each later defined by f o u r f o r m a t i o n s ( H a r l a n d , Wallis & Gayer, 1966). T h e u p p e r g r o u p is d o m i n a t e d by c a r b o n a t e s a n d the lower g r o u p by siliciclastics. It is o f N e o p r o t e r o z o i c (Late R i p h e a n to Sturtian) age f o r m i n g over a d u r a t i o n o f at least 200 million years a n d m a y r e p r e s e n t the d e v e l o p m e n t o f a subsiding i n t r a c r a t o n i c basin b e g i n n i n g w i t h r a p i d clastic s e d i m e n t a t i o n

N O R T H E A S T E R N SPITSBERGEN (following volcanic strata o f the u n d e r l y i n g g r o u p ) a n d w h i c h c h a n g e d into the stable c a r b o n a t e p l a t f o r m e n v i r o n m e n t o f the upper group.

7.7.1

Akademikerbreen Group ( H a r l a n d & W i l s o n 1956; W i l s o n 1961)

T h e A k a d e m i k e r b r e e n Series was described by H a r l a n d & W i l s o n (1956) with five c o n s t i t u e n t units each with u p to ten divisions. These were described in m o r e detail, p u b l i s h e d p o s t h u m o u s l y (Wilson 1961) w h i c h can h a r d l y be i m p r o v e d . T h e units were f o r m a l i s e d i n t o f o u r f o r m a t i o n s using the same n a m e s ( H a r l a n d , Wallis & G a y e r 1966). T h e g r o u p is very largely f o r m e d o f d o l o s t o n e s a n d limestones. Backlundtoppen Formation Draken (conglomerate) Formation Svanbergfjellet F o r m a t i o n Grusdievbreen Formation. S u b s e q u e n t l y the m a i n d e v e l o p m e n t s have been p a l a e o n t o l o g i cal with R u s s i a n studies o f k a t a g r a p h s , oncolites a n d s t r o m a t o l i t e s a n d by the A m e r i c a n studies o f m i c r o b i a l assemblages p r e s e r v e d in chert. The Russian studies were reported as follows: Raaben (1960, 1967); Golovanov (1967, 1976); Mil'shtein (1967-1976); Golovonov & Raaben (1967); Raaben & Zabrodin (1969); Mil'shtein & Golovanov (1979, 1983); Mikhaylova & Turchenko (1986) and with a study of carbonate in stromatolites (Fairchild 1991). The American studies as follows: Knoll & Calder (1983); Knoll (1984); Knoll et al. 1986; Swett & Knoll (1989); Derry et al. (1989); Knoll & Swett (1990). Bacldnndtoppen Formation, 360-700m, (Harland, Wallis & Gayer 1966). Originally this formation comprised an upper 'Backlundtoppen dolomite' unit with three divisions and a Lower Backlundtoppen oolite with three divisions (Wilson 1961). The formation is now described with the same six units or members, (Harland et al. 1992 confused B1 and B3). (B6) Upper Dolostone Mbr, 6-25 m, massive pale grey dolostone with large convex-downwards stromatolitic structures. These strata and the units below match well the Ryss6 rocks of Nordaustlandet. Wilson referred to this as 'dartboard dolomite'. (B5) Shale Mbr, 16-20m, dark quartzose and multicoloured shales. The shales are sharply distinguished from the dolostones above and below. The thickness is constant and four divisions can be traced extensively. 0.5 m quartzite, fine-grained, weathering orange; 1 2 m paper shales, purple, quartzose non-calcareous; 10 m paper shales green, quartzose non-calcareous; 5.10m mixed beds as above, weathering dark. (B4) Middle Dolostone Mbr, 150-250 m, massive pale grey dolostones. This main unit can be recognized everywhere by its resistant lithology, pale multicoloured weathering and absence of stratification. It is largely composed of massive or separated Collenia colonies with breccia and oolitic matrix. The stromatolitic structures are up 20 cm across and a metre high. There is some replacement by chert. (B3) Oolitic Dolostone Mbr, a dark grey dolomitic limestone, rusty weathering and irregularly bedded. Pale to coloured pisolitic and oolitic dolostones, often silicified, alternate with massive black limestone. (B2) Lower Dolostone Mbr, medium grey, pale-weathering coarsely stratified Dolostone with chert and Collenia. (B1) Oolitic Limestone Mbr, 100-300 m, thickly bedded dark grey to black cherty limestones with numerous oolitic and pisolitic bands, with subordinate flake conglomerates. Pale weathering dolostones also occur 0.5 to 4 m. Knoll, Swett & Burkhardt (1989) reported on biotas from the Backlundtoppen Formation which preserves five distinct microfossil assemblages occurring in distinct sedimentary environments. They noted a possible age range of 700-800 Ma but without explicit correlation (Sturtian on the scale used here). Draken (conglomerate) Formation, 25-300m, cliff-forming shale-like strata, dominantly dolomitic and with stromatolites, oolites and indeed all the lithologies in the Backlundtoppen Formation but with the distinguishing thick conglomeratic facies and the remarkably rich microbial cherts. Wilson (1961) listed 18 distinctive beds and with detailed descriptions especially of the gravelstones and flake conglomerates.

119

The succession may be summarized as follows: The upper 150m is of undifferentiated cherty dolostones, pale grey weathering grey-white, mainly thick bedded with abundant intraformational conglomerates often silicified with patchy or continuous bands of chert up to 1 m. There are also bands of Collenia dolostone, dark grey shale and oolitic or pisolitic facies. The lower 150m is formed of three or four units, similar to the above, separated by a variety of thinner beds. The formation as a whole is laterally variable in thickness and facies. This formation is noteworthy because of the rich microbial biota exquisitely preserved in the chert. (Knoll 1982a, b & c; Swett & Knoll 1985; Maliver, Knoll & Siever 1989, Knoll, Swett & Mark 1991; Fairchild, Knoll & Swett 1991). The key paper by Knoll (1982 in the Journal o f Paleontology) described an intraformational flake conglomerate with well preserved microfossils in silicified shards or microbial (cyanobacterial) mats formed in a lagoonal environment with at least three cyanobacterial benthos and a dozen planktonic taxa. Overall, of 28 taxa described, 8 were new. Knoll (1981) compared the biota with that of Bitter Springs. It is richer and probably of similar age (700-800 Ma). Svanbergfjellet Formation, 100-625m, is of limestone, dolostones, and Collenia strata divided by Wilson (1961) into four members, followed by Harland, Wallis & Gayer (1966) and Harland et al. (1992). It is a sequence of alternate limestones and dolostones. ($4) Upper Limestone Mbr, 3-115m, because there is some similarity with the Draken Formation, and some sections recorded are of doubtful correlation, the type section must be from Akademikerbreen where Wilson recorded seven units from the top: quartzites; black oolitic limestones; limestones and dolomitic flags; siliceous and dolomitic flags; calcareous flags; black oolitic limestones; and limestones and dolomitic flags. ($3) Stromatolitic Dolostone Mbr, 52-230m, this unique 'Svanbergfjellet Collenia' facies is penetrated by large scale stylolites and separated by thinner layers of multicoloured siliceous paper shales. ($2) Lower Limestone Mbr, 15-130 m, this member forms steep cliffs of thick bedded grey to black limestone generally iron stained and referred to by Wilson as 'Bolster Beds'. The base contains ochre-weathering cherty concretions up to 30 m and the upper beds are paler. (S1) Dolostone Mbr, 30-150m, this member of well bedded pale-grey dolostones and dolomitic limestones with black and white chert flattened concretions. The greater thicknesses are in Akademikerbreen which thin greatly in the north to Kluftdalen. More details were given by Wilson (1961). Butterfield, Knoll & Swett (1988 & 1994) reported on the paleobiology of the Neoproterozoic Svanbergfjellet Formation in which exceptional preservations of organisms including sphaeromorphic acritarchs, cyanobacterial sheaths, multicellular algae, complex protistan vesicles and probable heteromorphic bacteria providing an exceptional window on Neoproterozoic peritidal life. Of 63 forms reported 56 were treated taxonomically. These and other Proterozoic biotas are discussed in Chapter 12. Grusdievbreen Formation, 865 m. This unit was a series originally separated from the Akademikerbreen Series which comprised the above three formations as in Harland & Wilson (1956) and Wilson (1961) and included in the Upper Middle Hecla Hoek. Harland, Wallis & Gayer (1966) combined it with the three overlying formations to make the Akademikerbreen Group. The Grusdievbreen Formation (Series) was divided by Wilson (1961) into upper and Lower Limestone members with six and four divisions respectively as in Harland et al. (1992). (G2) Upper Limestone Member, 465 m in Akademikerbreen (6) Limestones banded, pale grey (5) Limestones banded, pale grey-black (4) Limestones banded, pale grey. (3) Limestones banded, pale grey-black. (2) Limestones banded, pale grey with massive base (1) Calcareous flags mainly red-brown. (G1) Lower Dolomific Member, 400 m in Akademikerbreen (4) Dolostone, pale weathering (3) Limestone black (2) Dolomitic Limestone, shales and flags (1) Dolostone, pale weathering.

7.7.2

Veteranen Group ( H a r l a n d & W i l s o n 1956; W i l s o n 1958)

3.8 k m , m a i n l y siliciclastics. T h e V e t e r a n e n Series was established by H a r l a n d & W i l s o n (1956) a n d described in m o r e detail by

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Wilson (1958) as the L o w e r Middle H o e k and divided as follows: Oxfordbreen Series U p p e r Veteranen Series Middle Veteranen Series L o w e r Veteranen Series Whereas this a c c o u n t follows Wilson, the n o m e n c l a t u r e was modified by H a r l a n d , Wallis & G a y e r (1966) and H a r l a n d e t al. (1992), as h e r e u n d e r , m a k i n g the four series into four formations respectively Oxfordbreen, Glasgowbreen, K i n g b r e e n a n d K o r t b reen. Hjelle (1965) c o n t r i b u t e d some additional detail and K n o l l & Swett (1985) reported on further microbial biotas, the oldest k n o w n f r o m Svalbard. H a r l a n d & G a y e r (1972), on the basis of likely sedimentationsubsidence rates in the strata above the Veteranen G r o u p , suggested that the age might well range from a b o u t 875 M a back to 900 or 920 Ma. Milstein & G o l o v a n o v (1979) m a d e the V e t e r a n e n G r o u p as o f late R i p h e a n age, say 670-950 M a on the basis o f s t r o m a t o l i t e s and microphytolites. K n o l l & Swett (1985) c o m b i n i n g their results f r o m material collected f r o m each of the formations with correlative rocks in N o r d a u s t l a n d e t suggested an age between 800 and 900 M a on the basis of acritarchs. The evidence is consistent, but not constraining. O n a likely correlation of the underlying Planetfjella G r o u p and the K a p p H a n s t e e n igneous rocks of N o r d a u s t l a n d e t , of w h i c h the latter has yielded ages in the range of 9 5 0 M a (Gee e t al. 1995), these estimates appear to be reasonable, but not established. M o r e o v e r the m a x i m u m age of the strata three groups below and beneath an u n c o n f o r m i t y appears to be 1190 M a (Gee & H e l l m a n 1997). All the above results are consistent with an age between 800 and 900 M a and the 4 k m of variegated, often shallow water strata could well have spanned that interval. Oxfordbreen Formation, 550 m. The formation, divided into two members, is of distinctive beds of dolomitic shales, quartzites and limestones, so distinguished from the overlying Grusdievbreen F o r m a t i o n dolostones and limestones. It was described by Wilson (1958) from five m a i n areas: Faksevfigen, lower C h y d e n i u s b r e e n , Polarisbreen, O x f o r d b r e e n - G r u s d i e v b r e e n , and T r a n s p a r e n t b r e e n . The following succession was described from Faksevfigen. Fulmarberget Shale Mbr, 210 m, (0.7) 140 m, pale highly dolomitic shales with some pure dolomite-siltstone, with a conglomerate near the top. (0.6) 70 m, interbedded pale and bright red-brown slightly dolomitic shales with layers of pale dolomitic quartzite. Eupiggen Mbr, 450 m, (0.5) dark green-grey shales and brown-weathering pale quartzose flags; (0.4) Passing into blue-black shales and flags. (0.5) & (0.4) non-calcareous and total 210m; (0.3) 90m, dark quartzose flags interbedded with dark limestones, some dolomitic; (0.2) 10m, grey-black bedded limestone-siltstones; (O. 1) 140 m, mixed dark beds. Glasgowbreen Formation, 540 m. Harland & Wilson (1956) referred to this unit as the Upper Veteranen Series, comprising two formations: Glasgowbteen Greywackes and Glasgowbreen Quartzites. Wilson (1958) divided the Glasgowbreen Greywackes into three units: Upper Greywacke, Upper Quartzite and Lower Greywacke the former Quartzite Formation becoming the Lower Quartzite. These four units were followed by Harland, Wallis & Gayer (1966) and listed as members by Harland et al. (1982). The following is from Wilson (1958) who described essentially only two lithological types. (G4) Upper Greywaeke Mbr is of clean greenish-black, fine-grained greywacke, finely laminated with darker and less dark laminae separated by carbonaceous fitness. (G3) Upper Quartzite Mbr is of coarse-grained, thickly bedded, pale pinkish, cross-bedded quartzites of uniform lithology. (G2) Lower Greywaeke Mbr of consistent lithology similar to (G4). (G1) Lower Quartzite Mbr is a prominent consistent unit similar to (G3) without other lithologies and with a sharp lower boundary. Knoll & Swett (1985), while generally confirming Wilson's successions questioned whether greywackes were not mixed tidal sandstones and shales. If so they would be consistent with the environments of formation of the quartzite members. Kingbreen Formation, c. 1500m. These rocks could first have been described by Fairbairn (1933, pp. 451-2) but not in sequence. Harland &

Wilson described the Middle Veteranen Series with three formations: Cavendishryggen Quartzites (300 m), Cavendishryggen Limestone (250 m), Galoistoppen Beds (c. 1000 m). The same rocks were described in considerable detail by Wilson (1958) from observations around Heklahuken, Dun6rbreen, Glintbreen, northern Veteranen, mid Veteranen, lower Chydeniusbreen and south Ny Friesland. He noted that the Middle Veteranen Series differed from the upper and lower series by much greater variety of strata. He divided the Galoistoppen Beds into upper and lower. Harland, Wallis & Gayer (1966) introduced the formation name and further division names, so making three members as listed by Harland et al. (1993) and followed here with Wilson's descriptions. 'Two thin lava bands occur at different horizons and localities. These are the only extrusions known from Ny Friesland in the Middle & Upper Hecla Hoek' (Wilson 1958, p. 313). Kingbreen Fm (K3) Cavendishryggen Quartzite Mbr was described by Wilson in three divisions. Harland, Wallis & Gayer (1966) followed by Harland et al. (1992) in systematising the naming of the units, without further explanation. To clarify the usage it is proposed to apply these two names to Wilson's observations pending further investigations as follows. Rheanuten Beds The upper division (of Wilson 1958) consists largely of 'black-coated' flags and shales with the same greenish quartzites as the middle division; greywackes and calcareous beds are subordinate. 4 m above its base is the 0.5m band of vertically jointed lava altered largely to calcite, chlorite in which the relic phenocrysts can be seen. Blfinuten Beds The Middle division (of Wilson 1958) is of dark uniformly medium-bedded, pale green-grey medium to fine-grained quartzites without other lithologies. The Lower division (of Wilson 1958) is of massive bands of variously tinted cross-bedded pure quartzite with thinner partings of rusty weathering quartzose shales and flags with few layers of dark dolomite limestone. Trail marks are common. (K2) Bogen Limestone Mbr. This unit is the renamed Cavendishryggen Limestone of Wilson (1958) which he described in six divisions (p. 317) only listed here. (6) 35 m, shales (5) 50-70m, calcareous beds (4) 4 35m, quartzose beds (3) 50 70 m, calcareous beds similar to (5) (2) 50 m, quartzose beds (1) 30m, limestones and dolostones. (K1) Galoistoppen Mbr. Following Wilson this is divided in two. Upper division Wilson listed 5 units at Faksevfigen (5) 180in, an assemblage of distinct lithologies including cream bands of cross-bedded fine dolostone with desiccation cracks and trail marks and fine green layers alternating with coarse cross-bedded pink quartzite. (4) 140m, mainly scree-covered mixture of rock types. (3) 30m, brightly coloured paper shales with dolomitic flags and a ferruginous quartzite bed. (2) l i0m, comprising 10m bands of differently brightly coloured noncalcareous paper shales. (1) 9 m, conspicous white quartzite marks the base. Lower division c. 700 m in Glasgowbreen, c. 450 m at Faksevfigen The upper 60m is finely laminated dolostone. The main rock type is of thickly bedded dark medium-grained quartzose greywacke. Two bands of altered lava, about 1 m thick occurred on the south side of Skinfaksebreen snout. One band has a pillowed upper surface and both have chilled margins top and bottom. Kortbreen Formation, 1200 m. This lowest unit of the middle Hecla Hoek, the Lower Veteranen Series was divided by Harland & Wilson (1958) into Veteranen Quartzites, 2150 m, and Veteranen Limestones, 10 350m. With more detailed observations Wilson (1958) described successions at Heclahuken, Dun6rbreen, the Fakse glaciers, northern Veteranen, midVeteranen, and Terrierfjellet and reduced the original estimate of thickness. Two members follow the original division. The Quartzite Mbr is of uniform petrology reflecting typical shallow water deposits. Rich in iron the colour varies, possibly in different tectonic situations. The Limestone Mbr, varies greatly in thickness and structure, but is always present beneath the quartzite member. Best seen by the Fakse glaciers is of dark grey limestone, siltstones, alternating with dolomitized equivalents. There are abundant oolites and some pisolites.

NORTHEASTERN SPITSBERGEN The Lower boundary of the Veteranen Group separates it from the Planetfjella Group in the Stubendroffbreen Supergroup (Section 7.8.1 below) and this boundary referred to (e.g. Harland et al. 1992) as the Veteranen Line has been the subject of some controversy (e.g. Gee et al. 1995; Manby & Lyberis 1995). Wilson (1958) summarized the field evidence from Harland & Wilson (1956) together with further observations. He reported (p. 306) on the boundary in at least six localities - from north to south: Sorgfjorden, Dun~rbreen, Skinfaksebreen, northern Veteranen, midVeteranen, and Terrierfjellet. Only in Terrierfjellet and northern Veteranen is there any evidence of structural irregularity at the contact. However, the stratigraphy corresponds so closely with that of Skinfaksebreen and midVeteranen, where the strata show every sign of conformity that such a fault is not likely to be of great throw. Further 'the metamorphic grade is always transitional across the boundary, though sometimes as in Dun6rbreen the transition appears to be rather rapid'. Further evidence is cited to conclude that the earlier views of Harland & Wilson (1956) are confirmed.

7.8

Stubendorffbreen Supergroup: succession ( o f H a r l a n d e t al. 1966)

This unit is the Archean of Nathorst (Suess 1888), the basement complex of Tyrrell (1922), the Western schists and gneisses of Fairbairn (1933) and the Lower Hecla Hoek of Harland & Wilson (1956) and of Bayly (1957). The whole or part of this unit, estimated at 12 + km thick, was a candidate for a proto-basement complex to the Hecla Hoek then reduced to the Atomfjella Complex (Harland, P o l a r R e s e a r c h 1997). The rocks are entirely metamorphosed and crop out throughout western N y Friesland: unlike the overlying units they have a range of igneous and sedimentary compositions suggestive of episodes of volcanic and related igneous activity almost throughout. Harland & Wilson (1956) distinguished three series: Planetfjella, Harkerbreen, and Finnlandveggen which were simply converted to group status as by Harland, Wallis & Gayer (1966). Abakumov (1965) and Krasil'shchikov (1965) proposed the Atomfjella Complex to combine the Harkerbreen and Finnlandveggen groups, confirmed by Harland (1996) as proto-basement. In anticipation of gravity surveys in Svalbard (Howells 1967); the Stubendorffbreen Supergroup, as an example of Caledonian basement, was sampled for density determinations (Howells, Masson-Smith & M a t o n 1977). F r o m the early sixties the St Petersberg group followed and extended the earlier Cambridge work but their detailed maps have not been published. However the map by Johansson, Gee et al. (1995), although based on Cambridge maps, added detail from Abakumov's unpublished work. This enabled mapping to the east of AsgSrdfonna to delineate the lower boundary of the Planetfjellet Group and in the south with the correlation especially of the Rittervatnet Formation. These revisions are included in the diagrammatic maps (Figs 7.3 and 7.4).

7.8.1

The Planetfjella Group (Harland & Wilson 1956; Harland et al. 1966; Wallis 1969)

The group, 4.7km, is dominated by metasediments with an acid volcanic component which increases downwards. Unlike the underlying groups no basic compositions (amphibolites) have been recorded. A distinctive feature of these feldspathic schists is their foliation and their spindle-shaped feldspathic aggregates. Fig. 7.4. Distribution of the Stubendorffbreen Supergroup in Ny Friesland (after Harland et al. 1992 and Johansson et al. 1995). The contact between the Planetfjella and Harkerbreen groups may have been mapped by Abakumov because the authors do not comment on it. It shows successive thinning and truncation northwards of the Sorbreen, Vassfaret and Bangenhuk formations, which is one of the arguments here for an unconformity without orogeny between the two groups to the east of the Atomfjella Antiform. Northern part revised after Witt-Nelson, Gee & Hellman (1997).

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Others have w o r k e d on these rocks, notably B l o m s t r a n d (1864), Odell (1927), Fleming & E d m o n d s (1941), Bayly (1957), G a y e r (1969) a n d K r a s i l ' s h c h i k o v (1979) w h o r e n a m e d the unit the M o s s e l h a l v o y a G r o u p - a j u n i o r s y n o n y m . M e t a m o r p h i c facies range from chlorite facies at the top to amphibolite facies with garnet, kyanite and staurolite at the base (Witt-Nilsson, Gee & H e l l m a n 1997). The two f o r m a t i o n s presently defining the g r o u p were described in detail in the n o r t h by Wallis (1969) from which paper the following s u m m a r y has been taken.

Vildadalen Formation, c. 3250m. First regarding the upper contact, Blomstrand (1864) in the north recognised the stratigraphically conformable contact with the overlying rocks and the transitional nature of the sedimentary lithologies. Fleming & Edmonds (1941) noted the conformable nature of the boundary in the Gullfaksebreen area and the uniform nature of the uppermost Planetfjella rocks from Sorgfjorden to Veteranen. The conclusions of Harland & Wilson (1956) confirmed by further work by Wilson (1958) as recounted for the overlying formation were further confirmed by detailed studies of Wallis (1969) who divided the formation into four members: Ros~nfjella, ,~lbreen, ,~lryggen and Tfibreen which alternate two lithologies. Whereas Wilson (1958) confirmed the consistency of the succession above the Planetfjella Group in which the lowest limestone unit is almost always present. Wallis (1969) showed that the uppermost (Ros6nfjella) member of the Vildadalen Formation is consistently adjacent to it. These observations in the north confirm Harland's reconnaissance traverses across the boundary (Harland & Wilson 1956). (V.4) Ros~nfjella Mbr, 1500m, is of fine-grained dark grey-green subpelites. The top 20 to 50m may be interbedded with 5m thick brown dolostone layers. 400 m below the top of the member are two further brown to orange dolomitic subpelites 15 m and 30 m apart. Down the succession, that is towards the west, deformation and recrystallization increase from a quart~chlorite-sericite assemblage with some plagioclase and tourmaline to increasing grain size, lightening of colour in which biotite and muscovite dominate. In the lowest 100 m horizons of pale pink feldspar phenocrysts up to 3 mm occur in a fine ground mass. These are the highest horizons in the PlanetfoJella Group with feldspar megacrysts. (V.3) Albreen Mbr, 400m, is distinguished by its contrasting beds of dolomitic and calcareous marble, subpelites, psammites and quartzites of which a 100m unit near the base is massive and persistent. The thicknesses and persistence vary along strike. The subpelites and psammites in particular are intensely folded and exhibit quartz hinges and feldspar megacrysts. (V.2) Alryggeu Mbr, 500 750 m, is of uniform subpelite lithology similar to that of (V.4) though somewhat lighter. Psammitic bands have recrystallized, biotite is the dominant mica, garnets are common and distort the ubiquitous microfolds with detached quartz hinges. The rock thus forms a foliated gneissose rock with quartz tension gashes. A characteristic Planetfjella Group lithology is a crenulated, foliated, megacrystic feldspathic psammite in horizons up to 10m thick with pink potash and grey plagioclase feldspars. Large feldspars up to 5 cm occur in a matrix of quartz-muscovite + plagioclase + biotite. Feldspar may constitute 50% of the rock. (V.1) Tfibreen Mbr, 450-800m, is analogous to the Albreen Member with horizons of marbles and quartzites as well as the characteristic feldspathic Planetfjella lithologies. Wallis (1969) gave three different successions in the north each with 5 - 6 units but varying greatly between them. The most constant feature is the basal marble unit. The distinctive Planetfjella lithologies may constitue half the bulk of the formation. Flfien Formation, 1500 m. The formation is distinguished from that above by the much greater occurrence of feldspar, yet retaining the typical close lamination of the Planetfjella Group. Whereas Harland, Wallis & Gayer (1966) noted three divisions, Harland et al. (1992) followed that paper rather than the later work of Wallis (1969) which is followed here with eight informal divisions. (F8) Upper subpelite division, 120m, of massive garnetiferous subpelites to psammites in which garnets reach 2 cm, with strongly contorted crenulation boudin necks with marked biotite foliation interrupted by the garnets. (F7) Upper variable division, 30-45 m, with marbles, subpelites and craggy feldspathite. Garnet megacrysts reach 4 cm. (F6) Upper felspathic-psammite division, 180m, is a massive craggy greyweathering unit with orthoclase and plagioclase feldspar megacrysts often euhedral, quartz axes produce rodding and there is extensive boudinage. (F5) Middle subpelite division, 40m, dark brown-weathering gneissose, garnet~luartz-subpelite, equigranular and little crenulated.

(F4) Lower felspathie-lrsammite division, 150m, pink-weathering, massive feldspathic psammite well foliated, crenulated with pink microcline megacrysts but mostly equigranular. (F3) Lower subpelite division, 30 m, is transitional from (F4) with increase in pelitic composition (biotite and garnet). (F2) Banded psammite division, 75m, with repetition of units, 0.5-1,0m each, with quartz-psammite base grading upwards into better laminated more pelitic composition. (F1) Lower variable division, 60m, a banded psammite passing downwards into more biotitic psammite in which crenulation produces marked lineation. The genesis of the distinctive rocks of the Planetfjella Group is discussed with problems of the origins of the metamorphic rocks of the whole supergorup in Section 7.9. To anticipate, it is clear that the Planetfjella Group derived much sediment fi'om an acid volcanic source. Wallis (1969) discussed the question in detail and showed, from a plot of four sections through the group from north to south of Mosselhalvoya, that the megacrystic felspathic lithologies thicken northwards so indicating a source in a direction with a northerly component. East-west comparisons are not possible in the steeply dipping strata. The Lower boundary of the Planetfjella Group with the Harkerbreen Group was discussed by Wallis (1969) who referred to the description of the northern outcrops of the Harkerbreen Group by Gayer & Wallis (1966). It is not so well exposed as the upper boundary and has yet to be mapped in detail. The contrast is marked from the laminated semipelitic Planetfjella lithologies to the Harkerbreen pure granular psammites with amphibolites. Moreover, 'the uppermost amphibolite unit seems to occur at the same general horizon' in relation to the boundary. The contact is well exposed for 5km from the NW corner of Mosseldalen where the boundary is taken below a 3 m persistent marble band above pale grey and pink equigranular granulose, slightly felspathic psammites interbanded with amphibolites, apparently concordant. However at many localities the contacts are thrust and indeed the whole complex has suffered intense tectonism. Krasil'shchikov (1973) showed a conformable upper contact, but a major break beneath his Mossel Series (Planetfjella Group). The revisions to the map afforded by Abakumov's mapping (in Johansson et al. 1995) provides clear evidence of discordance whether stratigraphic, tectonic or both, quite contrary to the same mapping which is consistent with a concordant upper contact of the Planetfjella Group. Exposures east of ~,sgfirdfonna show Vassfaret Formation in contact with Planetfjella rocks whereas in northern Ny Friesland the contact is with Rittervatnet and Polhem formations and in southern Ny Friesland with the Sorbreen Formation. Thus there would appear to be a somewhat progressive overstep of Harkerbreen Group Formations northward with a net loss of about 2 kin. Johansson et al. (1995) made this contact a 'major thrust'. This is confirmed by further mapping in the north (Witt-Nilsson e t al. 1997).

7.8.2

The Harkerbreen Group (Harland & Wilson 1956; Bayly 1957; H a r l a n d et al. 1966; G a y e r & Wallis 1966; G a y e r 1969)

The H a r k e r b r e e n G r o u p , 3.5 4.0 km, comprises quartzites, psammites, feldspathic schists and granitic gneisses, with mainly c o n c o r d a n t amphibolites. First described in the south f r o m sledge parties based on Billefjorden ( H a r l a n d & Wilson 1956; Bayly 1957), the T o r d e n r y g g e n rocks are d o m i n a t e d by pink quartzites and the Bleikfjellet by variable compositions. A m o r e detailed, sequence in the n o r t h was a d d e d by G a y e r & Wallis (1966), but it lacks the u p p e r strata of the southern succession. H o w e v e r , the group was defined by H a r l a n d , G a y e r & Wallis (1966) as comprising the Sorbreen, Vassfaret, B a n g e n h u k , Rittervatnet a n d P o l h e m formations. The rocks of this g r o u p have been the subject of studies f r o m the earliest days to recent times including Blomstrand (1864), Tyrrell (1922), Fairbairn (1933), Fleming & E d m o n d s (1941), H a r l a n d (1941) which were essentially disconnected. These were followed by attempts at regional synthesis by H a r l a n d & Wilson (1956), Bayly (1957). A b a k u m o v (1965) and Krasil'shchikov (1965) i n t r o d u c e d the concept of a b a s e m e n t comprising the H a r k e r b r e e n and F i n n l a n d v e g g e n groups u n d e r the n a m e Atomfjella C o m p l e x w h i c h usefully combines the H a r k e r b r e e n a n d F i n n l a n d v e g g e n

NORTHEASTERN SPITSBERGEN groups. Harland, Wallis & Gayer (1966) in a revision of the whole Hecla Hoek sequence discussed especially the Harkerbreen Group facies and associated with further detailed studies by Gayer & Wallis (1966), Gayer et al. (1966) and Gayer (1969). Then, after an interval, a new interest developed partly with improved isotopic age determinations as by Gee, Schouenberg et al. (1992), Gee, Bj6kelund & Stolen (1994), Gee & Page (1994) and renewed speculation by Manby (1990), Harland et al. (1992), Manby & Lyberis (1995), Harland (1995), Johansson et al. (1995), Larionov et al. (1995), Witt-Nilsson et al. (1997), and Hellman et al. (1997). In reviewing the history of investigations of the Harkerbreen Group it may be overlooked that in the middle of Ny Friesland the extensive Asg~trdfonna ice obscured a large part of the lower Planetfjella Group and the upper Harkerbreen Group so that correlation of units between north and south and between east and west may in some cases need to bridge a gap of 50 km. Moreover, when the logistic routine was by pack-carrying or man-hauled sledge from the south or small boats from the north, and after the initial reconnaissance of the fifties, studies in the sixties focused either on the north or south. Thus coherent correlation with detailed mapping remains to be done. Therefore the later (unpublished) work by A b a k u m o v and colleagues is welcome in that it fills part of the previous unknown. The Harkerbreen Group has attracted particular interest because of the interpretation of a variety of facies. The amphibolites have been interpreted as meta-tuffs and lavas with some basic intrusives, and the feldspathites were argued to have originated as meta-tuffs, ignimbrites and arkoses also with some intrusives. This interpretation was based on the stratiform nature of the bodies - their stratigraphic persistence often of quite thin beds over long distances, and occasional gradational compositions (Harland et al. 1966). However, the largest granite-gneiss sheet the Camryggen gneiss in the south and later subsumed in the larger Bangenhuk Formation, seen best in the north, has been regarded as emplaced by thrusting (Gee, Schouenborg et al. 1992; Gee, Bj6rkelund & Stolen 1994; Gee & Page 1994; Johansson et al. 1995) and later as basement (Witt-Nilsson, Gee & Hellman 1997). These papers report on Precambrian isotopic ages in contrast to the earlier determinations compiled by Gayer et al. (1966). Moreover, the geochemistry of the rocks has been applied to interpret the tectonic environment of their formation (Manby 1990; Carlsson, Johansson & Gee 1995), but with somewhat equivocal conclusions. Igneous textures have survived later deformation in the core of some amphibolite bodies and there could be some dykes and sills amongst the greater volume of volcanic basic strata. Gayer & Wallis (1966) proposed a shallow marine environment with volcanic lands to the west. The Rittervatnet Formation contained the upper two psephites (a metatilloid) which served as strain as well as possible climatic indicators (Gayer & Wallis 1966). The lower psephite has been reinterpreted as a basal conglomerate of the Polhem Formation (Hellman et al. 1997). The Atomfjella Arch is a southward plunging antiform which exposed Finnlandveggen Group rocks in its core to the south and so separates the two limbs which, because of structural complications, are not easy to correlate. However, the plunge is variable as the antiform continues to the far north. Moreover, most work on the group has been done either in the north or in the south with less information from middle Ny Friesland concerning the Harkerbreen Group which is exposed mainly in the western limb seen in coastal valleys or east of Asg~trdfonna on the eastern limb. Figure 7.4 follows the formation boundaries as modified from Harland et al. (1992) according to Johansson et al. (1995) which incorporates not

only the new zircon age determinations but also the available improved mapping of Abakumov. However the structural interpretation in that map is speculative. The major fault depicted along the Veteranen Line (Johansson et al.) is not supported by sufficient evidence. Breaks in the Harkerbreen Group successions are marked as thrusts (later named by Witt-Nilsson, Gee & Hellman 1997). These are noted below but have yet to be demonstrated by detailed mapping.

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Stubendorffbreen Supergroup Atomfjella Complex (Krasil'shchikov 1965) Harkerbreen Group Tordenryggen Subgroup, 1 to 2 km. This subgroup was based on the cliff sections in Harkerbreen which expose massive quartzites and psammites of relatively uniform composition dipping E and east of the Atomfjella Antiform. They have not been investigated in detail. Sorbreen Formation. The formation was named for the glacier reaching the sea on the east side of Widefjorden where the shore exposes clean fissile quartzites so that athough it correlates with the lower part of the originally defined Bleikfjellet rocks in the eastern limb, there is no complete measured sequence - a conclusion that is not difficult to entertain after a close study of the Ny Friesland glaciers. Indeed, in the north the contacts are often faulted cutting out the upper Tordenryggen Subgroup or obsecured beneath the fjord to the west. It comprises the Dirksodden Nappe of Witt-Nilsson et al. (1997). The rocks are primarily quartzites and psammites with variable feldspar and other content as described by Gayer & Wallis. Some compositional banding exhibits cross bedding so confirming the sequence. Distinctive feldspathic bands occur as typical meta-tuff which extend much of the length of the Wijdefjorden coast, composed of tabular plagioclase and K-feldspar megacrysts in a feldspar-quartz matrix. Concordant amphibolite horizons occur throughout with thicknesses ranging from 1cm to 30 m. By colour and competence contrast the ubiquitous boudinage is especially evident. Typically with 60-70% blue-green hornblende and 40-30% plagioclase (An20 30) with accessories quartz, biotite, iron ore, titanite and apatite. Often megacryst garnets occur. In some horizons Manby and Harland in 1981 and 82 observed N S bands of mylonite (Manby 1990; Harland 1992). Gayer & Wallis described the lower boundary as transitional. Witt-Nilsson et al. made the lower contact the basal Dirksodden Thrust, with some related granitoid features which gave a 1750Ma zircon age (Larionov in Witt-Nilsson et al. 1997).

Bleikfjellet Subgroup Vassfaret Formation, 600 m, defined just south of Femmilsjoen (Five Mile Lake) of mixed composition with traceable horizons of psammite and feldspathite and where best exposed three divisions are recognizable. (V.3) 320 m, quartz-biotite-polymictite with bands of feldspar psammitcs and calcareous polymictites. Intense folding of foliation has resulted in quartz rods from fold hinges. (V.2) 40 m, of two distinctive units an upper calcareous-hornblende-biotitepolymictite with garnet and a lower banded epidote psammite separated by a sharp boundary. (V. 1) 240 m, predominantly polymictic with calcite epidote concretions and bands of foliated concordant amphibolites. From residual sedimentary structures the concretions are interpreted as syn-sedimentary. The formation is interpereted as formed in shallow water by rapid deposition with contemporary basic pyroclastic input. It would correspond to the top of the Bleikfjellet subgroup in southern Ny Friesland, and has been so mapped by Abakumov. Bangenhuk Formation, 2000m, this unit was first distinguished in the south as the Camryggen gneiss with distinctive spindle shaped feldspars in an intensely lineated massive feldspathite. It is continuous with the Bangenhuk Formation to the north coast where it is divided into two members as seen best in Femmilsjoen. However, it may well correlate with more layers than in the south where the Camryggen gneiss in the eastern limb is much thinner. Femmilsjoen Mbr, 1250m, at the type locality and thins to 500m to the north. It is a markedly lineated gneissose alkali feldspathite. Orthoclase and oligoclase form 50 to 60% with quartz and up to 36% mafic bands of biotite (up to 17%) hornblende (less than 10%), epidote and titanite. Garnet is rare. The section by Gayer & Wallis (1969) shows fine nearly evenly distributed amphibolite horizons within the member. Flatoyrdalen Mbr, 735m, named from the valley south of Royal Societybreen on the west of the arch in middle Ny Friesland, is said to thin to 260 m east of the arch. It is formed of banded lithologies with up to 47% of potash feldspar. It is typically a medium-grained, banded gneissose, quartzose or psammitic feldspathite with mafic bands up to 5 cm of tabular blue-green hornblende. Schistose amphibolites similar to those in the Sorbreen Formation occur throughout with both sharp and gradational contacts. Harland, Wallis & Gayer (1966) concluded that the sedimentary origin of the formation is shown by the compositional banding including psammites of undoubted sedimentary origin and by the amphibolites

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representing basic pyroclastic deposits. This was originally evident in the south where amphibolites of varying thicknesses from a cm to many metres are interbedded with clean quartzites making it likely that amphibolite bands in feldspathites have a similar origin. Early ideas of magmatic or metasomatic origins for the granite gneisses were abandoned. Local evidences of granites were interpreted as a melted volcanic stratum. The matter is for discussion below. Nevertheless a magmatic intrusive origin was postulated by Gee et al. (1992) and subsequently. It seems likely that the Bangenhuk Formation has a greater feldspar content in the north because the typical granite compositions are matched in the south by the much thinner Camryggen gneiss, as seen at the head of Smutsbreen. The corresponding thickness being made up of quartzites. These southern investigations noted that above the 'Camryggen gneiss' was the 'Bottfjellet Band' of similar facies but only about 10 m thick. The latter unit specially exhibited gradational marginal facies from quartzite or psammite, through transitional facies with conspicuous isolated feldspar megacrysts, to a fully feldspathic gneiss. These observations, at the height of the magmatic-metasomatic controversy on the origin of granites, seemed to rule out a magmatic origin and suggested a metasomatic transition (Harland 1959). That was before some of the immense variety of volcanic products was preferred to provide protoliths of the granitic gneiss (Harland, Wallis & Gayer 1966). Zircons from a granite and gneissic granite of the Harkerbreen Group have been analysed by U-Pb and 2~176 single crystal method and have yielded ages of c. 1700-1800Ma. One of these granites intrudes metasediments, indicating [a late Paleoproterozoic] age for at least part of the Harkerbreen Group (Gee et al. 1992). Gee et al. concluded that significant segments of 'pre-Caledonian' crystalline basement are incorporated in the base of the Caledonian pile in northeastern Spitsbergen. The samples analysed were from locations shown on their map at Brennkollen, Femmilsjoen, Flhtan and Rittervatnet. Manby (1990) reported detailed chemical studies: (Section 7.9.2 below). Further determinations consolidating the above conclusions were presented by Johansson et al. (1995) when the zircons were characterized as plutonic rather than volcanic. Volcanic zircons were also identified in some of the meta-tuffs. Petrographic as well as detailed geochemical studies on the granitoids were reported by Carlsson, Johansson & Gee (1995) who noted that the granitic compositions throughout are 'cogenetic members of a single fractionation series'. Because the igneous component of the Bangenhuk Formation, with 1750Ma zircons, was thought to be intrusive in the Vassfaret Formation, Witt-Nilsson et al. (1997) combined both formations into a Bangenhuken Complex as the Nordbreen Nappe. They accounted for the distinction between the two formations as 'extensive shearing resulting in decoupling between the Bangenhuken Complex granites and the Vassfaret Formation metasediments'. Johansson et al. (1995) recorded the boundary between the Bangenhuk and Rittervatnet Formations as a major thrust. Witt-Nilsson et al. named it the Nordbreen Thrust and the Bangenhuken Complex their Nordbreen Nappe. Rittervatnet Formation, 350 m (Gayer & Wallis) up to 500 m (Witt-Nilsson et al.). The formation crops out in the northeast and west of the Atomfjella Arch. Rittervatnet is the lake just north of Femmilsjoen. The variety of distinctive strata enable more reliable structural observations to be made. Three divisions were recognised in the west but are difficult to correlate with different lithologies in the east where psephites are noteworthy. (Gayer & Wallis 1966). (R3) 72m, psammites with subordinate thinly banded (up to l m) psammitic sub-feldspathites, feldspathites, biotite subpelites and concordant amphibolites. Epidote is abundant, up to 30%; hornblende is a largely altered to chlorite. (R2) 160 m, is of uniform graphite-pelite to subpelite with thin marbles and quartzite as well as the usual thin bands of foliated schistose concordant amphibolites. The graphite is distinctive in the pelites which contain up to 60% mica. Quartz may amount to 35% and garnet is always present. The pure marbles contain up to 80% calcite giving a sugary appearance. Quartzite bands up to 0.5 m have sharp boundaries. (RI) 160m, in the west is of four distinct units. A thick foliated garnet amphibolite makes a clear top to (R1) below which is a thick white marble with over 80% sutured quartz. The Rittervatnet Formation in the east, as seen for example on the mountains some 10km southeast of Mosselbukta, is of approximately the same thickness but of different facies. Most notable are the two psephites, one at the top and separated from the lower one by about 300 m of banded

psammite, polymictites, feldspathite and amphibolite and underlain by about 50 m of polymictite has the appearance of a meta-tilloid with a variety of stones in a pelitic matrix. The dolostones being most competent have been squeezed and extended to fish-shaped spindles with axial ratios N-S of 10:1, limestones were flattened to ratios of 20-30:1 Witt-Nillson (1996?) noted conglomerate stones elongated in ratios of 40 : 3 : 1. The pelite matrix presumably attained much higher ratios. These tilloids give a clue as to the degree of deformation suspected throughout the supergroup by the prevailing linear and foliated fabric and indicated positively by the ubiquitous boudinage, all indicating N-S extension and later interpreted as extreme transpression. The original tilloid sedimentation was most likely by dropstones into mud from floating ice in a marine environment. It may be significant that feldspathite stones are rare. The lower horizon stones can be matched with underlying lithologies. The upper horizon contains over 20% that were not matched in Ny Friesland. The overall sedimentary pattern of the Rittervatnet Formation suggests a shallow marine environment in which the banded lithologies appear to have spread from the east. The carbonaceous content must imply significant biogenic activity with anaerobic conditions in local deeper water. Miscorrelation of units across the Atomfjella Antiform has been resolved not only by identifying the distinctly older Instrumentberget Formation (Johansson et al. 1995), but also by reinterpreting a psephite (probably the lower one) of the Rittervatnet Formation as the basal conglomerate of the Polhem Formation (Witt-Nilsson et al.) Polhem Formation, 900+ m (Gayer & Wallis) to 5000m (Witt-Nilsson et al.), named from Nordenski61d's 1872-1873 winter base and the name of his ship, is composed mainly of coarsely banded psammites and amphibolites. Indeed their similarity to those of the Sorbreen Formation and uniform light colour has posed a mapping problem where the succession is not clear. The psammites contain 60% quartz, other minerals vary, the dominant second mineral being oligoclase. Muscovite generally exceeds biotite. Because of its uniformity of facies the formation has not been divided. Gayer & Wallis (1966) gave more mineralogical details. The amphibolite strata range from a few centimetres to 30m and some less altered facies are doleritic with ophitic texture and appear as intrusive bodies. Nevertheless, the dominant impression is of concordant volcanics. The Polhem-Instrumentberget contact is marked by a basal conglomerate, the lngstadsegga conglomerate (member), with large granitoid clasts decreasing upwards and yielding zircon ages identical to the underlying granitoid (Hellman et al. 1997). Instrumentberget (granitoid) Formation. This is a previously unrecorded unit from a small outcrop in northern Mosselhalvoya at Fl5tan (about 5 km south of Verlegenhuken). Johansson et al. (1995) reported granitoid samples with plutonic zircons giving U-Pb ages of 1720-1770 Ma, the least deformed with ages around 1750 Ma. They interpreted these from two sheet-like units. One of these the well known Bangenhuk Formation referred to above and the other newly distinguished as a lower unit beneath the Polhem Formation and exposed at Instrumentberget (southeast of Mosseldalen). The Instrumentberget exposure yielded an age of 1737 +46/-41 Ma suggesting a coeval intrusion time of 1750 Ma. The unit was placed as the lowest of the Harkerbreen Group formations.

Lower boundary of Harkerbreen Group. There is a s h a r p transition f r o m highly q u a r t z o s e a n d feldspathic rocks often with a m p h i b o l i t e s to a distinctive p s a m m i t e with calcareous facies. This b o u n d a r y was m a r k e d as a m a j o r thrust by J o h a n s s o n e t al. (1995). It a p p e a r e d in the core o f the A t o m f j e l l a A n t i f o r m a n d is consistently b o u n d e d on their m a p by R i t t e r v a t n e t a n d P o l h e m f o r m a t i o n s on b o t h E a n d W flanks a n d over a N - S distance o f 6 0 - 8 0 or even 1 2 0 k m . F u r t h e r m a p p i n g in the n o r t h shows the P o l h e m F o r m a t i o n and, f u r t h e r to the n o r t h , the I n s t r u m e n t b e r g e t Fl~ttan F o r m a t i o n each resting directly on rocks o f p s a m m i t i c calcareous facies similar to the S m u t s b r e e n F o r m a t i o n to the south. T h u s there a p p e a r s to be no evidence o f a m a j o r u n c o n f o r m i t y , b u t the base is defined as the R e k v i k a T h r u s t at the base o f the R e k v i k a N a p p e o f W i t t - N i l s s o n e t al. 7.8.3

Finnlandveggen Group ( H a r l a n d & W i l s o n 1956)

W h e r e a s this, the lowest g r o u p , c. 3 k m , in the Hecla H o e k C o m p l e x , is a c o m b i n a t i o n o f t w o quite different f o r m a t i o n s :

NORTHEASTERN SPITSBERGEN Smutsbreen and Eskolabreen, its original distinction as a group stems m o r e from its contrast with the overlying H a r k e r b r e e n G r o u p than f r o m similarity o f its constituents. This contrast applies most particularly with the Smutsbreen F o r m a t i o n which could not be confused with any overlying strata. On the other h a n d the Eskolabreen F o r m a t i o n with its feldspathites and amphibolites could be confused with the H a r k e r b r e e n G r o u p except for their interbedded schists and marbles and their distinct plutonic fabric. The Smutsbreen F o r m a t i o n is clearly a m e t a s e d i m e n t a r y calcareous unit of psammites, semipelites, calc-schists and marbles of a distinctive mauve hue, or brown to orange where the calcschists and marbles have weathered, and exceptionally with amphibolitic bands. The Eskolabreen F o r m a t i o n is a complex of acid and basic gneisses of coarse grain size suggesting a plutonic m e t a m o r p h i c environment. Amphibolitic banding is typical except for some pink gneisses. Whereas the Eskolabreen F o r m a t i o n has from the beginning been suspect basement and possibly confirmed isotopically, the Smutsbreen F o r m a t i o n is a coherent metasedimentary unit overlying it and underlying the H a r k e r b r e e n Group. Nevertheless M a n b y (1990), thinking that m o s t of the H a r k e r b r e e n amphibolites are intrusions, suggested that the general lack o f Smutsbreen basites beneath the H a r k e r b r e e n rocks makes the Smutsbreen F o r m a t i o n younger and so tectonically inverted. It was clear from H a r l a n d ' s (1941) study in Stubendorffbreen that considerable nappe structures are present, nevertheless the overall stratigraphic succession appears to be consistent (e.g. Balashov et al. 1993).

Smutsbreen Formation, c. 1000m, (Harland & Wilson 1956). Smutsbreen Formation is seen in an antiform beneath the Harkerbreen rocks (Fig. 7.8a) especially well in the cliffs north of Stubendorffbreen and it forms the outer core of the Atomfjella Antiform extending through Lemstr6mfjellet to Smutsbreen (Harland 1941). At first sight it is a dark pelite with distinct light marble bands which are valuable as marker horizons. The formation as a whole ranges in composition from a foliated psammite of distinctive mauve tint with quartz stringers, the axes of isoclinal folds, though garnetiferous pelites to calc schists and relatively pure marble in two principal horizons (Harland 1941). The Atomfjella Antiform extends southwards where the formation is more accessible from Billefjorden, but less well exposed along the northern moraine of Nordenski61dbreen. Tyrrell (1922) and Fairbairn (1933). Amphibolite bands do not characterize the Smutsbreen Formation contrary to the impression from Harland & Wilson (1956). Indeed since the early reconnaissance reported there the further work, especially that of Bayly (1957) resulted in a reappraisal by Harland, Wallis & Gayer (1966) as follows: ($2) Westbyfjellet Mbr, c. 500m, includes the Westbyfjellet and Einsteinfjellet marbles of Harland & Wilson (1956) and the upper part of the Stormerfjellet schists of Harland (1959). Five divisions were listed. (5) c. 100 m, dark medium-grained schistose garnetiferous mica semipelite (4) 0-20 m, impersistent marble (3) c. 100m, as (5) (2) c. 100m, massive marble dividing into two or three horizons and associated with highly calcareous pelites. (1) c. 200m, calcareous garnetiferous schistose pelites and semipelites weathering to a fine golden colour. (S1) Bohryggen Mbr, c. 700m, is equivalent to the lower part of the Stormerfjellet schists, and probably the Lemstr6mfjellet schists of Harland & Wilson (1956). It is of uniform coarse-grained, foliated, compositionally laminated, garnetiferous psammite/semipelite characterized by a mauve or purple sheen on fresh surfaces, and sigmoidal quartz fold hinges. It contains rare psammites and exceptional amphibolites (Harland, Wallis & Gayer 1966). Eskolabreen Formation, 2000+ m, Harland & Wilson (1956). The underlying Eskolabreen gneisses are the least understood; the members distinguished may be in stratigraphic sequence or may be digitations of a nappe (Harland 1941; Harland 1959) or separate thrust sheets, e.g. of basement. If there is a pre Hecla Hoek basement, it is likely to have been remobilized and so be obscured in this formation. On the other hand there is a general concordant compositional banding and foliation throughout. The conclusions of Harland (1941), Harland & Wilson (1956) and Bayly (1957) were revised by Harland, Wallis & Gayer (1966) who distinguished four members:

125

(E4) Einsteinfjellet Mbr, c. 100 m, is a massive pink-weathering gneissose feldspathite, associated with coarse-grained semipelites. (E3) Lemstriimfjellet Mbr, c. 700 m, is similar to those of the Einsteinfjellet Member but alternating with coarse amphibolites. (E2) Malmgrenfjellet Mbr, 100~00m, consists of coarse-grained semipelites together with impersistent marble horizons. (El) Sederholmfjellet Mbr, 500+m, is of interbanded feldspathic and amphibolitic layers distinguished by very coarse granite texture suggestive of a plutonic environment. This is the lowest unit exposed beneath ice and Carboniferous cover to the south. Larionov, Johansson et al. (1995) reported U-Pb determinations on zircons from the Eskolabreen Formation as exposed in Stubendorffbreen. A band of muscovite biotite gneiss gave 1770Ma. Two samples of granite gneiss yielded a pooled upper intercept age of 1766+ 10Ma which was taken to date the age of the intrusion of the granite protolith. The lower intercept age of 404+8 and a similar U P b titanite age recorded the Caledonian metamorphic event (?Early Devonian). The consistency of this result with ages from zircons in the Harkerbreen Group in northern Ny Friesland leave little doubt that the feldspathites in the Atomfjella Complex comprising both the Harkerbreen and Finnlandveggen groups were formed at about the same time or derived from a common source. The temptation to correlate the Harkerbreen and Eskolabreen rocks should take into account the marble content only of the lower rocks. Balashov et al. (1993) reported without detail a zircon age of c. 2415 Ma from the Eskolabreen Formation.

7.9 7.9.1

Stubendorffbreen Supergroup: genesis Petrology

In classifying these rock types Bayly (1957) described six m a j o r lithologies: (1) pink quartzites; (2) variable quartzites, (3) granitic gneiss; (4) calc-schist and marble; (5) feldspathic schists and (6) mafic rocks (Fig. 7.5a). Both granite gneisses and mafic rocks have an igneous composition whereas the remainder are of sedimentary origin and often with a variable and significant igneous c o m p o n e n t . The purely igneous compositions presented a problem. In addressing it, and to avoid genetic prejudice, Wallis et al. (1968, 1969) used a working objective classification of m e t a m o r p h i c rocks according to the m a j o r mineral group present: quartzite > 90% quartz; psammites 80-50% quartz; feldspathite > 50% feldspar; marble > 50% carbonate minerals; pelite > 50% alumino-silicates; and amphibolites > 50% pyrobole, hornblende is generally > 60%. The granite gneiss (or feldspathite) compositional range is smaller than in adjacent beds and the main c o m p o s i t i o n is typical o f low-melting-point mixtures so that the 'last consolidation' was probably from a liquid, not f r o m 'detritus'. Bayly preferred a product o f refusion rather than a primary magmatic origin. H a r l a n d et al. (1966) further concluded that magmatic intrusions could not have p r o d u c e d such consistent stratal relations along strike (100km). This required a c o n t e m p o r a r y protolith such as lava, pyroclastics, arkose or combinations. A pyroclastic origin could account for the margins with transitional composition of some units in which lava or ignimbite might constitute the centre. Bayly's m e t a m o r p h i c facies m a p is shown in Fig. 7.5b. Intrusive contacts of the feldspathites have been noted by all authors and typical granitic compositions agreed by all. However, most recent authors have resuscitated an original option that the feldspathites are n o r m a l granitic intrusions into a sedimentary sequence (Gee et al. 1992; Gee, Bj6rkelund & Stolen 1994; J o h a n s s o n et al. 1995; Carlsson et al. 1995), all having zircon ages between 1700-1800 Ma. Subsequently, w h e n it turned out that some metasediments could n o t be older than c. 1190 Ma, the granite was interpreted as basement, and only one f o r m a t i o n (of u n k n o w n age) was intruded, the other granites being basement (Hellman et al. 1997). The alternative hypothesis o f c o n t e m p o r a n e o u s volcanic origin with relict zircons from remelted granite m i g h t take into account

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Fig. 7.5. (a) Petrological character of units in SW Ny Frieslan, after Bayly (1957). The numbers refer to stratigraphic units at that time as follows: (1) Planetfjella schists; (2) Tordenryggen quartzites; (3) Bleikfjellet quartzites; (4) Camryggen gneiss; (5) Smutsbreen schists and marbles; (6) Eskolabreen gneisses; (7) Austfjorden gneiss; (8) Cambridgebreen gneiss; (9) Sorbreen quartzites. (b) Metamorphic character of units in SW Ny Friesland, after Bayly (1957). Reproduced by permission of Cambridge University Press.

the power of ignimbrite flows (e.g. Brannery & Kokelaar 1997). Volcanics can have local intrusive relationships. The mafic rocks ('amphibolite') appear all to be of basic igneous origin. Indeed exceptionally some rock masses retain an igneous texture. Harland & Wilson (1956), Bayly (1957), Harland (1959) and Harland et al. (1966) all preferred a basic volcanic environment with possible tufts, lavas, sills and occasional feeder dykes. Again the banded rocks would be contemporaneous or pene-contemporaneous (contra Manby 1990). Some layers (e.g. a few millimetres thick and tracable some 100m or more) are unequivocally sedimentary. Their sharp contacts with quartzite suggest a direct pyroclastic origin rather than denudation from a basic source rock. A high sedimentation rate in a proximal volcanic environment would explain the sharp contacts. Thicker layers could be lavas and the rare cross-cutting units could be feeder dykes. Exceptional metabasites, often preserving igneous textures, might be of later (Caledonian) origin (Harland et al. 1966; Wallis & Gayer 1969) and if so it might be an igneous episode in a transtensional regime (Harland 1971). Manby (1990) on the other hand favoured all amphibolite bodies to have originated during the

deformation phase. How much this, if any, was Phanerozoic remains to be determined.

7.9.2

Geochemistry

Manby (1990) described the chemistry of the acid gneisses and amphibolites of the Harkerbreen Group. Compositions in terms of most elements were tabulated. Amphibolite. The element abundances are of basaltic calc-alkaline to tholeiitic composition and slight differences do not appear to reflect any genetic differences, for example with regard to concordance or discordance. Interpretative assessments suggest affinities with volcanic arc basalts, transitional volcanic arcs, back-arc basins and mid-oceanic ridge basalts so that no unequivocal matching could be found. Manby concluded (p. 144) that the 'Harkerbreen amphibolites represent basaltic to calc-alkaline magmatism in a rifted basin behind a magmatic arc, above a mature subduction zone'.

N O R T H E A S T E R N SPITSBERGEN Gneiss. W i t h 6 5 - 7 2 % silica the alkali silica A F M plots s p a n the t r a c h y t e - r h y o l i t e - r h y o d a c i t e a n d g r a n o d i o r i t e field. M a j o r , trace a n d rare e a r t h e l e m e n t ratios are b r o a d l y similar to rhyolites a n d have n o t suffered significant c h a n g e s t h r o u g h s u b s e q u e n t m e t a m o r p h i s m . Detailed analytical d a t a were t a b u l a t e d a n d p l o t t e d with the c o n c l u s i o n o f a r h y o d a c i t i c to rhyolitic 'within plate' setting in a possible rifting A t l a n t i c type m a r g i n . T h e c o n c l u s i o n here is t h a t valuable as the d a t a are they d o not actually discriminate b e t w e e n a n y o f the conflicting h y p o t h e s e s .

Bangenhuk

granitoids. C a r l s s o n e t al. (1995) described the g r a n i t o i d c h e m i s t r y a n d a r g u e d t h a t the feldspathic gneisses o f the B a n g e n h u k F o r m a t i o n were d e f o r m e d granites as seen in t r a n s i t i o n a l occurrences. T h e low strain facies c o n t a i n large m e t a s e d i m e n t a r y xenoliths. T h e y c o n c l u d e d t h a t granites a n d g r a n o d i o r i t e s are a m a j o r c o m p o n e n t o f the B a n g e n h u k F o r m a t i o n . T h e y were classified as A - t y p e with respect to m o s t g e o c h e m i c a l p a r a m e t e r s . E l e m e n t d i s t r i b u t i o n has n o t been significantly d i s t u r b e d by t e c t o n o t h e r m a l events. T r a c e e l e m e n t d i s t r i b u t i o n indicates s o m e heterogeneities o f m a g m a source a n d later c o n t a m i n a t i o n . Trace e l e m e n t a b u n d a n c e s , R E E p a t t e r n s a n d N d i s o t o p e characteristics indicate s o m e crustal c o n t r i b u t i o n r a t h e r t h a n direct m a n t l e d e r i v a t i o n . A g e d e t e r m i n a t i o n s suggest a single closely related magmatism.

7.9.3

Isotopic ages

T w o d a t a sets affirm the Silurian age o f the u b i q u i t o u s latest m e t a m o r p h i s m a n d tectogenesis. Krasil'shchikov et al. (1964) reported a whole rock analysis by K - A r on a biotite gneiss from Verlegenhuken (recalculated) 365 Ma, and Gayer et al. (1966) recorded K Ar determinations, especially from biotite in rocks in the NW corner of Ny Friesland. Garnet-mica schist from E end of Instadegga 419 + 5 Ma Paragneiss from E end of Instadegga 434 • 7 Ma Mica schists from N of Mosselbukta 426 + 8 Ma Paragneiss from Femmilsjoen 436 4- 9 Ma North shore of Adolfbukta 422 4- 6 Ma Except for the 365 Ma result all fall within the limits of the Silurian Period as estimated in Harland et al. (1990, 408.5-439.0Ma) and in this work (417-443 Ma). New data by more sophisticated technology confirm the above results, but more precisely as Silurian mainly Middle. Gee & Page (1994) reported 4~ determinations on eight samples. Muscovite from garnet-mica-schist at Rittervatnet 414-t-3 Ma Hornblende from amphibolite at Rittervatnet 428 4-4 Ma Hornblende from amphibolite at Rittervatnet 443 4-5 Ma Hornblende from amphibolite at Rittervatnet 424 + 3 Ma Hornblende from amphibolite at Polhem 421 + 3 Ma Hornblende from amphibolite at Polhem 423 + 4 Ma Hornblende from amphibolite at Polhem 421 + 3 Ma Muscovite from feldspar mica schist at Planetfjella 416 4-3 Ma Harland e l al. (1990) estimated the Wenlock interval at 424 to 430.4 Ma. From the scale adopted in this work one would be Llandovery, two Lochkovian, the rest Wenlock. The above data do not discriminate between the formations or even groups of the Stubendorffbreen Supergroup. Late Paleoproterozoic ages have been obtained as follows. (i) Manby & Lyberis (1991) reported Sm-Nd age determinations on Harkerbreen amphibolites yielding an age of 1757+90. The amphibolites were said to cut schistosities but few structural or stratigraphic details were given. However, analytic data and sample treatments were not provided for an independent check. (ii) Gavrilenko & Kamenskiy (1992) obtained 1.8 Ga from ultramafic rocks in Mosselhalvoya separating the Polhem Formation from the Planetfjella Group. An adjacent biotite rock yielded 500 Ma, both by K-Ar and Ar-Ar methods. Zircons tell a similar story surviving the Caledonian metamorphism and recording c. 1750 Ma events as follows.

127

(iii) Gee, Schouenborg, Peucat, Abakumov, Krasil'shchikov & Teben'kov (1992) recorded from granitic gneisses of northern Ny Friesland seemingly Bangenhuk Formation samples which yielded e. 1750 Ma ages. Two samples one from (a) an aplitic granite on the south side of Femmilsjoen and (b) one from a reddish grey gneissic granite, 100m south of Fl~ten north of Mosselhelvoya yielded zircons, which were carefully sorted. By U - P b analysis: Sample (a) from different fractions gave on upper intercept age: 1809 + 165/- 122 Ma Sample (b) gave zircons with less discordant ages of 1778 + 53/-45 combining all data a range of 1778 4-30 Ma was suggested. (iv) Gavrilenko & Kamenskiy (1992) by K - A r and Ar Ar methods on an ultrabasic body, presumbly stratigraphically below the Planetfjella Group, obtained a range of values through 271,469, 780, 1870Ma. (v) Balashov, Larionov, Gannibal, Sirotkin, Teben'kov, Ryungenen & Ohta (1993) gave an earliest Proterozoic age for zircon in the Eskolabreen gneiss south of Stubendorffbreen. The rock is a coarse-grained, feldspar porphyroblastic, garnethornblende-biotite gneiss with 25-30% plagioclase (An2045), 30-40% K-feldspar, 10% biotite, 1-2% each of hornblende and garnet with accessories of apatite, zircon, monazite and opaques and secondary chlorite, sericite and epidote. U - P b isotopic isochron gave upper intercept of 24154-34Ma. Balashov et al. argued that the Smutsbreen formations are conformable so that this age would apply to the Finnlandveggen Group as a whole. (vi) Johansson, Gee, Bj6rkelund & Witt-Nilsson (1995) gave further U-Pb zircon ages from seven further samples, both north and south, in the Harkerbreen Group. Ranging 1720-1770 Ma they centred on 1750 Ma, the zircons being of plutonic rather volcanic origin and intrusive within the units. From further mapping, two mappable granitoid sheets were distinguished. The Bangenhuk Formation extending the length of Ny Friesland and a lower Instrumentberget Formation exposed at Instrumentberget and already sampled at Fl~tan, both in the north. Moreover, a felsic metavolcanic within the Sorbreen Formation yielded 1750 + 8 Ma by the same method. Johansson, Gee & Larionov (1995) gave further support for an age range between 1720 and 1770Ma of six U - P b zircon results from undeformed granitoids within the Bangenhuk Formation. The seven results were as follows, the numbered localities being shown on Fig. 7.4 and suggested magmatic crystallization events. (1) Brennkollen 1759+ 1 9 / - 1 4 M a 1748 4- 8 Ma (2) Einsteinodden (3) Gyldensk61dholmane 1728 + 2 1 / - 1 8 Ma (4) Reinbokkbreen 1766+43/-35 Ma 1724 + 14 Ma (5) Reinbokkdalen (6) Bangenhuk 1739 + 49/-43 Ma (7) Intrumentberget 1737 + 46/-41 Ma The zircons indicate magmatic crystallization events. Determinations by Rb-Sr from six of the above gave c. 1650 Ma and Sm-Nd analysis indicated a significant crustal contribution to the granite magmas. They concluded that a homogeneous volcanic origin of the quartzofeldspathic gneisses can be discounted. Whether the foliation was Proterozoic or Caledonian is uncertain, but a Caledonian age was preferred. They suggested that the crystalline basement prior to Caledonian cover was subject to Paleoproterozoic or earlier orogenic deformation prior to the 1750 Ma granite intrusions. (vii) Larionov, Johansson, Teben'kov & Sirotkin (1995) dated the Eskolabreen Formation at c. 1770 and 1766Ma. U P b dating of zircons from a band of muscovite biotite gneiss within the Eskolabreen Formation in the Atomfjella Antiform at Stubendorffbreen gave c.1770Ma. Zircons from two samples of granitic gneiss pooled an upper intercept age of 1766+ 10Ma indicating the granite intrusion. A lower intercept age of 404 4- 8 Ma and a similar age by U - P b on titanite, i.e Early Devonian. (viii) Gee & Hellman (1996) using Pb-evaporation determinations of detrital zircons in the Smutsbreen (metasedimentary) Formation from two samples, each with 14 or 15 crystals analysed, obtained the following values: (1) 2 of 1190 Ma; 5 of 1560-1710 Ma; others ranging 990-2570 Ma and (2) 2 of 1200-1300Ma; 2 of 1650Ma, others ranging 1100-1880Ma. From the above they interpeted a major unconformity with a basement-cover relationship. (ix) Hellman, Gee, Johansson & Witt-Nilsson (1997) interpreted basement-cover relationships from three groups of determinations of rocks in one succession using Pb-evaporation methods on zircon crystals.

128

CHAPTER 7 The Instrumentbergetgranitic gneiss from five crystals obtained a mean of 1740+3Ma which, combined with data reported by Johansson et al. (1995) on the same rocks by conventional U Pb work with zircons, gave a mean of 1735 • 13 Ma. The Ingstadsegga Conglomerate resting on the granitic gneiss contained large clasts of similar composition, two samples of which gave respectively three zircon ages of 1739 • 2 Ma and 2 of 1738 • 5 Ma. The overlying quartzites of the Polhem Formation from one sample of seven grains all spanned 1743-2040 Ma; another, also of seven grains, gave the following 1317+7; 14984-6; 1510• 1868• 1971+7; 2712-1-9 and 2716 • 5 Ma. Other crystals gave 1452 • 5; 1999 • 27; 2572 4- 8 and 2805 • 20 Ma. These were all detrital grains sampling the sediment sources then exposed, and the lowest values give a maximum age for the Polhem Formation.

7.10

7.10.1

The Hecla Hock Complex: mid-Paleozoic structure and metamorphism Fold and nappe structure

The overall structure of Ny Friesland comprises fold systems with a dominant N N W - S S E strike with fold axes plunging north or south, generally 10 ~ or less. The fold pattern is modified by the batholiths which both truncate some and deflect other strata. Emplacement by stoping was followed by pushing aside the adjacent strata with attenuation after the igneous body had attained sufficient strength (Fig. 7.6). Otherwise no significant discordant structure has been confirmed except for unconformities at the lower boundary of the Planetfjella Group and the Polhem Formation, and the major thrust in Mosselhalvoya of the Planetfjella Group onto the Polhem Formation. The folds are thus remarkably homoaxial. The possibility remains that earlier discordant structures have been transpressed into concordant attitudes by extreme shear. The long established boundary below the Hinlopenstretet and Lomfjorden supergroups has been referred to as the Veteranen Line. (Harland e t al. 1992). East of it the quartzites, greywackes and carbonates of the Lomfjorden and Hinlopenstretet supergroups have behaved competently except for the shales, mainly Polarisbreen Group, which occur in tightly pinched synclines. The main fold pattern with the minor oblique faults stands out because of the contrasting lithologies of the various rock units. In the north the less competent rocks, especially the Polarisbreen Group rocks, have been tectonized and metamorphosed to chlorite facies which contradicts the view (e.g. M a n b y 1990) that the Veteranen Line delineates the metamorphic rocks. West of this Veteranen Line (VL) all the rocks have been metamorphosed and generally penetratively tectonised. The gross structures may be of recumbent folds probably with attenuated lower limbs. An altogether larger scale structure is the Atomfjella Arch or Ant• a major structure of variable plunge and exposing within it the Finnlandveggen Group rocks the oldest of which occur in the widest outcrops to the south. East of the Atomfjella axis strata dip eastwards, often steeply. To the west westward dips predominate, but not with the same regularity. Recumbent folds or nappes drape over the Arch with an apparent westward vergence. The observed recumbent fold hinges would be anticlines on this interpretation. Manby's cross-section illustrating easterly vergence (1990) depended on the strata in the nose of an eastward verging recumbent fold coinciding with his proposed faulted contact (Veteranen Line) over a distance of 50-100 km and also depended on correlating gneisses of the Harkerbreen Group with gneisses of Finnlandveggen Group, which hardly match the Fig. 7.6. Structural map of Ny Friesland (simplified with permission of Cambridge University Press from Harland et al. 1992). AA, Atomfjella Ant• BP, Raudfjellet Pluton; BFZ, Billefjorden Fault Zone; CP, Chydeninsbreen Pluton; LFZ; Lomfjorden Fault Zone; NP, Lomonesovfonna Pluton; VL, Veteranen Line.

NORTHEASTERN SPITSBERGEN above observations. In any case both large and small near-isoclinal folding is ubiquitous and clearly in need of more than the reconnaissance work on which these speculations are based. Chocolate-tablet boudinage in the flat limbs of the early nappes would be the result first of E - W extension during nappe emplacement and later of more intense N-S extension during transpression. The latter structure is dominant everywhere west of the VNL (Harland 1959; Harland et al. 1992). This N-S extension was first interpreted as escape tectonics responding to indentor compression (e.g. Harland & Bayly 1958; Harland 1959). When this seemed untenable the transpression concept was introduced Harland (1971). The initial collision tectonic phase to the east of the Veteranen Line was one of upright or westerly vergent folding and to the west was one of thrusting and nappe formation, producing a stack of nappes determined to a large extent by the competance contrast of the stratal pile. Because the sequence of strata crops out consistently through the pile of nappes, it is reasonable to suppose that the thrusting hardly disturbed the stratal sequence except in the extreme north. The nappe stack of Witt-Nilsson, Gee & Hellman (1997) below the Planefjella Group overthrust is thus, each on a thrust of the same name. Dirksodden Nappe = Sorbreen Formation Nappe Dirksodden Thrust Nordbreen Nappe

= Bangenhuken Complex = Vassfaret Formation intruded by Bangenhuk Formation Nordbreen Thrust

Rekvika Nappe

= Rittervatnet Formation Polhem Formation Instrumentberget-F15tan Formation Rekvika Thrust Smutsbreen Formation

Sinistral transpression then predominated causing the linear fabric and shear zones referred to below (7.10.2). The stack of thrusted strata was arched into the Atomfjella Antiform, which, because of its N-S continuity, suggests transpressional control. The extreme transpression that developed in a series of N-S shear zones and almost ubiquitous mineral lineation and boudinage, could have displaced sinistrally the rocks along the Veteranen Line some 100km north of the nappe fronts further west. Consequently attempts at E - W cross-sections (for example the structure shown in fig. 3 of Witt-Nilsson et al., with thick nappes and excised roots) may result from 200% E - W structural shortening, but with greater N-S shear. At a late stage in the sequence was the emplacement of the Caledonian batholiths which were also subject to some transpression.

7.10.2

Fabric and shear zones in the Stubendorffbreen Supergroup

The earliest schistose-gneissose textures are related to the largescale recumbent folds with foliation parallel to the bedding and containing quartz feldspathic segregations and then to transpression. Quartz and micas were ductile throughout relative to feldspars, pyroboles, and garnets. Feldspathite gneisses have been more intensely deformed than amphibolites. Porphyroblasts in gneisses exhibit rotation (sinistrally in plan). These contrasting competences have permitted widespread boudinage which is conspicuous with

129

MOSSELBUKTA

MURCHISONFJORDEN

WIJDEFJORDEN ~

HINLOPEN U

w ~ d~L~ WIJDEFJORDEN

. ~ O ~ L ~ , , L7

W4-1 " L2 / AUSTFJORDEN

"- ~

-

_N O ~ K A P P

~ ' ~ t ~ ' ~ T ~~ . ~ ~ r

LS"'" " L9"

VETERANEN M2 "

~I-,~OGEN

MI

E

CHYDENIUSBREEN

.....

E

NEWTONTOPPEN

_

I]~VAI~VAI

Fig. 7.7. Diagrammatic cross-sections across Ny Friesland from Harland's 1954 unpublished Sedgwick Prize Essay. Rock units L1 and L2 were then thought to be the oldest rocks, but are now generally regarded as belonging to the Harkerbreen Group. U, M, L refer to the three Hecla Hoek supergroups.

colour and competency contrast as between pale quartzite and black amphibolites. Boudins may be rectangular (then often rotated) or ductile when quartz, chlorite and/or calcite have grown at the points of rupture. Lesser contrasts have led to a less conspicuous foliation boudinage as indicated by a pervasive mineral lineation. The mineral lineation indicates extension, but cannot quantify the ratios. Boudinage typically suggests at least 1:2 ratios. The Rittervatnet Formation, with the meta-tilloid, contains relatively competent fish-shaped dolomitic marble megaclasts with axial ratios of 1:10. Less competent calc-marble megaclasts string out with ratios of 1:20 or 1:40 and still less competent matrix could thus have effected extensions of at least 1:100. In the schistose horizons a later folding phase is recorded in crenulation and kink zones associated with chloritization of biotite and hornblende. Concordant mylonite zones are found, especially in the Planetfjella Group and in the Harkerbreen Group adjacent to the Billefjorden Fault Zone.

7.10.3

The Billefjorden Fault Zone (BFZ)

The kinematic history of the BFZ is discussed in the next chapter and Chapter 16 where Devonian structures on the west are considered. Evidence of penetrative tectonization east of the main fault is part of the above considerations as they affect Harkerbreen rocks west of the Atomfjella Antiform (Fig. 7.7). In the south, Svenbreen and H6rbyebreen (and north to the west at Zeipeldalen) are exposed up to 3 km E - W of chlorite schists and gneisses bounded westwards by the Balliolbreen Fault and in the east by the Pyramiden Fault. This is named the Cambridgebreen Shear Zone. Pink grey gneisses with concordant chlorite schists appear to have retrograded from amphibolite to green schistfacies. Feldspars have been sericitized and quartz-rich beds tend to mylonitic texture. The chlorite-rich rocks indicate a late (post-Silurian) brittle shear phase, evident also in the (possibly rotated) island of Bjornesholmen off the coast of Austfjorden. Further north along the east of Wijdefjorden, Reinbokkdalen, Dirksodden and Gunvorbukta are exposed extensive green schist facies with retrogressive metamorphism as indicated above. At these localities and further north (e.g. Sorbreen) quartz-feldspathic rocks show fine-grained grey slate-like zones with feldspar megacrysts. These were shown by Manby in 1981 to be mylonites often with sharp margins to pink or grey gneisses. They utilize steep foliation in the folds. Sinistral rotation in the megacrysts is evident in the horizontal plane.

130

CHAPTER 7

Fig. 7.8. Three interpretive west-east sections across Ny Friesland. (a) Harland (1941). The Atomfjella antiform is shown with west verging nappes where A (in the centre) is the upper part of the Eskolabreen Formation and B the Smutsbreen Formation. C is now known to belong to the Harkerbreen Group as, indeed is also A in the east, seen at a distance in 1938 and colour correlated with A. (b) Johansson et al. (1995) shows the same Atomfjella antiform in Northern Ny Friesland with the new Instrumentberget unit between the Rittervatnet and Smutsbreen formations. The boundary between 'Middle Hecla Hoek' and the Planetfjella Group, which is argued here to be conformable, is shown as a fault across which there is no continuity. On the other hand the major unconformity claimed in this work between the Planetfjella Group and Sorbreen Fm is not distinguished here (reproduced with permission of Cambridge University Press). (e) Manby & Lyberis (1995) agree with this work in showing sinistral strike-slip zones at Austfjord and in the Eolusletta shear zone. They show recumbent folds verging eastwards in contrast to (a) and the Planetfjella Group is tectonically concordant with the Lomfjorden Supergroup. The uppermost formation of the former maps concordantly with the lowermost formation of the latter through a distance of nearly 130 kin, so the recumbent anticline is shown in (c) would be unlikely to maintain that juxtaposition for such a great distance (reproduced with permission of Blackwell Science).

7.10.4

PlanetfjeUa schists

West of the Veteranen Line (VL) are the Planetfjella Group gneisses and schists, with a conspicuous sinuous or crenulated foliation. There is also a N - S extension lineation with aligned feldspar megacrysts, and in addition retrogressive zones containing mylonites. These characteristics are explained as a shear zone with horizontal displacement. The zone coincides with favourable steep bedding attitudes so there is no obvious truncation of strata. The VL is simply a stratigraphic boundary between the Lomfjorden and Stubendorffbreen Supergroups. A large part of the three or more kilometres of Planetfjella strata are sheared and effect a significant displacement. This was referred to as the Eolusletta Shear Zone by Manby & Lyberis (1995) (Fig. 7.8) ~Vildadalen Formation. With present evidence of stratigraphic continuity between the Veteranen and Planetfjella Groups the Veteranen Line is not a major terrane boundary nor even a major discontinuity as indicated in the sections of Gee & Page (1994) and of Manby (1990, 1995).

The boundary between the Planetfjella and Harkerbreen groups may well be faulted, but essentially represents an unconformity between the Atomfjella Complex and a relatively unbroken succession- Planetfjella through Oslobreen groups. But it may not be a major unconformity, a great time hiatus, and certainly not a Proterozoic orogenic episode or terrane boundary.

7.10.5

Kinematic interpretation of transpressive shear in the Stubendorffbreen Supergroup

Stratigraphic evidence for considerable sinistral displacement, at least along the Billefjorden Fault Zone will be considered in Chapters 8 and 16. The structures and textures indicated above are consistent with such large scale displacement. Throughout the terrane west of the VL strong lineation fabrics and boudinage or augen gneisses are evident. At first these were thought to be the result of extreme squeezing between vice-like lithosphere blocks (Harland & Bayly 1958; Harland 1959) with lateral escape on a model later

NORTHEASTERN SPITSBERGEN termed indentor (Taponnier et al. 1982) and applied by Manby (1990) and Gee (1986), Ohta (1994) and Gee & Page (1994). On this basis the sheared rocks would result from squeezing out horizontally N and S. However, analysis of the structural evidence replaced this concept by the transpression hypothesis (Harland 1971) in which the whole of the Stubendorffbreeen terrane had suffered extreme oblique compression. It explains the ubiquitous, though not totally consistent, evidence of sinistral shear seen from above. It was suggested that transpression could be an intermediate phase between compression and transcurrence. The later transcurrence or strikeslip being most evident in the Cambridgebreen Shear Zone. Moreover, the shear movements were of at least two generations. The earlier (Silurian) transpressive shear with the main tectogenesis took place forming kyanite etc at depth. The later (Devonian) strike-slip, when much of the overburden had been removed, led by retrogressive metamorphism to chlorite. To anticipate, a case is made that transcurrence (or pure strike-slip continued through Early and Mid-Devonian time along this Cambridgebreen zone and that the Svalbardian (Late Devonian) tectonism was the result of a compressive component (i.e. transpression) leading to final docking of the two terranes. The extraneous evidence for the BFZ suggests displacement of hundreds of km so separating quite distinct terranes. The evidence within Ny Friesland also suggests sinistral displacement along the VL or just west of it, but not of the same, and certainly not of greater magnitude, perhaps only 50 to 100 km. This is because while structural and metamorphic facies are different across the VL the stratigraphy is consistent over at least 100 km of the line mapped in Ny Friesland (e.g. Harland & Wilson 1956; Wilson 1968; Wallis 1969; Harland et al. 1992; Harland 1995).

131

7.10.6 Metamorphism The principal effects of tectonism and deep burial are seen in the metamorphic facies throughout the western part of Ny Friesland. The geosynclinal pile was estimated roughly at 18 km before the Silurian tectogenesis which must have greatly increased the overburden so that even the Polarisbreen strata, originally only about 1 or 2 km from the ?top was sheared and preserved in chlorite facies, whereas the deepest staurolite-kyanite facies was plotted along the Atomfjella Antiform by Bayly (1957) in Figure 7.5b. If some of the thickness is the effect of stacked thrust sheets it hardly affects the calculation. The Caledonian contribution to deep burial would thereby be no less. During the progressive Ny Friesland Orogeny the most intense deformation, with stratal thickening in the west, would have been accompanied and followed by both transpressional attenuation and active erosion. The resulting deposits are not preserved, but may have thickened the overburden of the strata away from the orogenic axis to the east possibly promoting the Polarisbreen Group metamorphism. To the west, according to the strike-slip hypothesis developed in this volume, the site of the orogenic debris would be more than 200 km to the southwest. The preserved Devonian strike-slip along the Billefjorden Fault Zone retrograded amphibolites of the Harkerbreen Group to chlorite schists, the overburden by that time having been greatly reduced. As a preliminary to gravity surveys of Svalbard, Howells & Masson Smith (1977) measured the density of representative metamorphic rocks from Ny Friesland; but the survey, begun by F. J. Vine (CSE) was never completed.

Chapter 8 Northwestern Spitsbergen W. B R I A N

HARLAND

with a contribution with PAUL

A. D O U B L E D A Y

8.1 Cenozoic volcanic rocks of the Woodfjorden area, 133 8.1.1 Pleistocene volcanic rocks, 133 8.1.2 Miocene plateau lavas (Sorlifjellet formation), 134

8.4.6 Conclusion on Krossfjorden Group correlation and deformation, 144 8.4.7 The Richarddalen Complex, 145

8.2

8.5

Structure, 145

8.5.1 8.5.2 8.5.3 8.5.4 8.5.5 8.5.6 8.5.7 8.5.8

The Billefjorden Fault Zone (BFZ), 146 The Andr~e Land-Dickson Land terrane, 147 The Breibogen Fault (BBF), 148 Biskayerfonna-Holtedahlfonna Terrane (BHFT), 148 The Raudfjorden Fault (RFF), 150 Western Northwest Terrane, 150 The Pretender Lineament, 151 Timing of deformations, 151 Offshore geology (W.B.H. & P.A.D.), 152 The Yermak Plateau, 152 Sjubrebanken, 152 Danskoya Basin, 153 Norskebanken, 153

Mesozoic, Permian and Carboniferous cover, 134

8.2.1 Basal B0nsow Land Supergroup unconformity 134 and outliers, 134 8.2.2 Lamprophyres at Krosspynten, 135 8.3

Liefde Bay Supergroup, 135

8.3.1 Andr6e Land Group, 135 8.3.2 The Red Bay Group, 138 8.3.3 Siktefjellet Group, 140 8.4

The 'crystalline' rocks, 142

8.4.1 8.4.2 8.4.3 8.4.4 8.4.5

Early work, 142 Magmatic intrusions, 142 Migmatites and gneisses, 143 The Western Northwest Terrane formations, 144 The Biskayerfonna-Holtedahlfonna Horst formations, 144

Northwestern Spitsbergen is bounded by Billefjorden and Wijdefjorden in the east and by the coastline in the north and west round to the southwest by Kongsfjorden (Fig. 8.1). The southern boundary overlaps with the Central Basin (Chapter 4) and central western sector of Spitsbergen (Chapter 9) along Kongsfjorden and Sveabreen. At this boundary Devonian and older rocks are unconformably overlain, and finally obscured to the south, by the cover of Carboniferous through Paleogene strata. This sector contains Andr6e Land, Albert I Land, Haakon VII Land, James I Land and northern Dickson Land. It is deeply penetrated by fjords and largely covered by ice. Apart from Quaternary sediments and volcanics, Cenozoic plateau lavas and the overlying platform sequence (Carboniferous through Paleogene) to the south, the main consideration here is with Devonian sediments, mid-Paleozoic migmatites and granites, and Precambrian metasediments. The Northwestern sector is bounded and divided by faults. The eastern boundary is delineated by the Billefjorden Fault Zone (BFZ) and the southwestern boundary is the postulated Kongsfjorden Hansbreen Fault Zone (KHFZ). These faults separate the Central Province respectively from the Eastern and Western provinces. Two main N-S oriented faults divide the sector into three terranes: the Raudfjorden Fault (RFF), and the Breibogen Fault (BBF) (Fig. 8.1) as noted by Holtedahl (1914). The three terranes are introduced below. (1) The Andr6e Land-Dickson Land Terrane is a large area of Devonian strata bounded by the Breibogen Fault Zone and the Billefjorden Fault Zone. (2) The Biskayerfonna-Holtedahlfonna Terrane is a N-S belt bounded to the west by the Raudfjorden Fault and to the east by the Breibogen Fault. It is complex of a Precambrian horst and an Old Red Sandstone graben and has been referred to as the Liefdefjorden Terrane and Haakon VII Land Block. (3) The western northwest terrane, situated west of the Raudfjorden Fault Zone, largely comprises Albert I Land and is dominated by crystalline. Precambrian rocks that have suffered a major Caledonian tectonothermal event. This chapter addresses first the rock units (youngest first excepting the ubiquitous glacial and beach deposits) and then the structure of the region as a whole and of the individual terranes.

8.1

C e n o z o i c volcanic rocks o f the W o o d f j o r d e n area

The area around Woodfjorden contains small outcrops of Neogene and Pleistocene volcanic rocks. They form two distinct groups:

8.6

8.6.1 8.6.2 8.6.3 8.6.4

Neogene plateau lavas on the summits of the hills to east and west of Woodfjorden, and Pleistocene volcanic centres along or close to the Breibogen Fault zone. No other Neogene subaereal outcrops are known from Svalbard.

8.1.I

Pleistocene volcanic rocks

Three centres of Quaternary volcanic rocks occur along the trace of the Breibogen Fault zone, to the SE of Bockfjorden in eastern Haakon VII Land. The fault trends N N W - S S E and juxtaposes Precambrian marbles and gneiss to the west against Devonian sedimentary rocks in the east. The presence of hot springs and recent volcanic centres along the trace of the fault was originally noted by Hoel & Holtedahl (1911), Von Post (1912) and Hoel (1914), although further work was not undertaken until the 1960s (Gjelsvik 1963; Burov 1965; Semevskiy 1965). Recent work, from which the following review is collated, has mainly concentrated on detailed petrological and geochemical studies of the rocks (mantle xenoliths in particular) found within them, and their tectonic implications (Fumes, Pedersen & Maaloe 1986; Genshaft & Ilupin 1987; Amundsen, Griffin & O'Reilly 1987; Skjelkvgde et al. 1989; Tuchschmid & Spillmann 1992). Three volcanic centres are located at Sverrefjellet, Sigurdfjellet and Halvdanpiggen (Fig. 8.1). Field relationships. At Sverrefjeilet an eroded strato-volcano 3 km across with a relief of 506 m is exposed. Warm springs occur within 5 km along the line of the Breibogen Fault which separates Precambrian marbles to the west from Liefde Bay strata to the east. Reworked volcanic material forms marine tarraces along the edge of Bockfjorden. The volcano appears to be constructed of about 80% fragmented material including marble and about 20% lava and some rare tufts. All outcrops are shattered by frost action. The cone, into which a cirque has cut, is made largely of pyroclastic layers from 2 cm to several metres thick which contain lapilli and bombs. Lava flows consist of either pahoehoe flows up to 2 m thick, or pillowed flows up to 5 m thick which are commonly interbedded in sequences of up to 15 flows. The pillowed flows have formed high walls, consistent with an interpretation that they were erupted into water in proximity to a glacier wall. Sub-horizontal lava tubes have also been noted. All lavas contain a large proportion of xenoliths, typically constituting 15-20vo1% of the flow but up to 50vo1% at the base of flows. The xenoliths are up to 15 cm in diameter, and consist predominantly of Cr-diopside spinel lherzolites with minor occurrences of basaltic cumulates and granulites.

NORTHWESTERN SPITSBERGEN

BBF Breibogen Fault RFF Raudfjorden Fault

13 M611enfjorden 14 Sigurdfjellet

133

|

Fig. 8.1. Simplified map of NW Spitsbergen, based on various sources including Geological Map of Svalbard 1:500 000 Sheet G3 (Hjelle & Lauritzen 1982), Hjelle (1979) and Harland (1985). The black triangle, locality 6 (Krosspynten) denotes a number of Lamprophyre dykes of possible Carboniferous age.

134

CHAPTER 8

Signrdfjellet is situated 20 km south of Sverrefjellet. The volcanic centre forms a ridge 4.5km long, 200-250m wide and up to 250m high, with a maximum altitude of 1100 m. Eruptions at Sigurdfjellet would have involved fissure-like behaviour. Volcanic deposits comprise breccia, lapillistone, agglomerate, unlayered pyroclastic rocks, and rare lava flows over a topographically varied surface on both sides of the fault. The pyroclastic rocks are commonly ash deposits containing lapilli of vesicular basalt and volcanic bombs. The latter mainly have cores consisting of mantle xenoliths. Agglomerates include large clasts of Precambrian marble and gneiss, and Devonian sandstone. Late stage vents a few metres wide cut across earlier deposits, and contain unlayered pyroclastic rocks. Quaternary volcanic rocks in Halvdandalen occur at three separate localities within the valley. Unlike the localities described above, these lie 5 km east of the Breibogen Fault, over Devonian sedimentary rocks. At Halvdanpiggen there is a 250 m high volcanic neck, containing pyroclastic breccia and basalt. The former consists of 60-70% xenoliths and basaltic blocks with xenoliths within an altered glassy ash matrix. The basalts form multiple intrusions and also contain xenoliths composed of pyroxenite, spinel lherzolite and amphibole megacrysts. A 5m wide volcanic neck found at Olavstfirnet which again consists of basalt with xenoliths. This volcanic neck is cut by two later dykes. At Haraldknattane, three tuff-breccia vents are exposed, each containing xenoliths formed under conditions of high-pressure, and fragments of country rock. This volcanic edifice is also cut by two dykes. The rocks from all three volcanic centres have similar geochemistry, with a small range in major and trace element composition. They all lie close to the nepheline basanite/nepheline hawaiite compositional boundary, and were derived from primitive magmas, typical of intraplate alkaline volcanism. The xenoliths (for details see Furnes, Pedersen & Maaloe 1986; Amundsen, Griffin & O'Reilly 1987) are derived from mantle depths and indicate a rapid rise of the magma through the crust, probably without any residence time in crustal chambers. Amunden, Griffin & O'Reilly (1987) predicted depths of between 27 km and 50 km, wheras Tuchschmid & Spillmann (1992) thought they were probably derived from a depleted garnet-lherzolite mantle at depths greater than 60 km. There has been a general consensus amongst workers on these rocks that they erupted before and during the last major glacial period on Spitsbergen. The early work of Hoel & Holtedahl (1911) and Hoel (1914) considered the volcanoes to be of latest Quaternary age as they saw no evidence for glacial erosion. Semevskiy (1965) thought them to have formed between 4000 and 6500 years ago based on molluscan dating of uplifted marine terraces in Bockfjord that contained volcanic debris. An age of less than 0.7 Ma was proposed for Sverrefjellet and Sigurdfjellet by Halvorsen (1972) based on paleomagnetic dating. SkjelkvAle et al. (1989) evaluated the age of Sverrefjellet as lying between 0.1 Ma and 0.25 Ma based on available information on the timing of glacial maxima in the region. They thought Sigurdfjellet to be the same age, but Halvdandalen to be older due to the greater degree of weathering and its reversed paleomagnetic polarity (Halvorsen 1972). Analysis of the petrological and geochemical characteristics of the volcanic rocks, and particularly the mantle xenoliths, indicates that the crust beneath NW Spitsbergen is 27 km thick. At depths of 17-20km it consists of mafic granulite, below which there is a transition zone of granulites interlayered with pyroxenites and lherzolites. Below 27 km is mantle defined by the dominance of spinel lherzolite. A geotherm, constructed by Amundsen, Griffin & O'Reilly (1987), indicates temperatures significantly higher than those described in other intraplate alkaline provinces, This is consistent with an interpretation that the volcanism was due to the rise of a mantle plume beneath the area, associated with rejuvenation of the Yermak hotspot. 8.1.2

Miocene plateau lavas (Seidfjellet formation)

Exposures of fiat-lying lavas on the summits of some of the hills SE of Bockfjorden and in Andr~e Land were first documented by Hoel

& Holtedahl (1911). They have recently also been reported from a single locality in eastern Ny Friesland (see Chapter 7) (Tebenkov & Sirotkin 1990) which considerably extends the area which they may have originally covered. The several lava flows are taken as members of a single, once extensive unit named informally as the Sorlifjellet, corrected to Seidfjellet, formation after one of the principal mountains where it occurs. No strata are known above it. The flattopped mountains in Dickson Land, capped by lavas, are Tavlefjellet, Sorlifjellet (1036m) Okstindane, Vaktaren (1226m), Svartpiggen (1328m), Risefjella and Paleontologryggen (1200m). Some of these are shown in Figs 1.4. and 21.1. Volcanic lavas overlie Devonian sedimentary rocks at various scattered localities in Andr6e Land (3G Hjelle & Lauritzen 1982) and are interbedded with scoriaceous units in places (e.g., Tavlefjellet), together forming stacks of up to 15 flows. Tuchschmid & Spillmann (1992) described a 150 m thick succession of lava flows from Risefjella 3-5 m thick showing evidence of magma mixing and exhibiting columnar jointing. Elsewhere, Hoel & Holtedahl (1911) reported a 155m thick succession, and Burov & Zagruzina (1976) suggested a total thickness to be up to 275m. There have been no interbedded sedimentary rocks reported, nor any signs of internal erosion, suggesting that the volcanic pile was formed rapidly. The lavas are largely unaltered, and commonly vesicular. They appear to be relicts of extensive flows on a peneplane that has since been dissected. Petrological and geochemical analysis of lavas from Bockfjord area and Andr6e Land by Lussiaa-Berdov-Polue & Vidac (1973), Prestvik (1978) and Tuchschmid & Spillmann (1992) showed that they are largely enriched olivine tholeiites with some olivine basalts. Tuchschmid & Spillmann thought that the magmas probably originated from the upper, spinel-lherzolite dominated part of the mantle, at depths of less than 40-50 km. Phenocrysts (olivine and plagioclase) probably crystallized at low pressures in mid-crustal magma chambers, at depths of less than 15 km. The age of the lavas was widely regarded as postdating Early Cretaceous peneplanation. The first radiometric ages, by Burov & Zagruzina (1976), gave ages of 60 + 25 Ma and 22 + 10 Ma, but due to their large errors and variation were not widely accepted. The following year, Prestvik (1978) presented K-Ar ages of 11.5+ 1.2 Ma and 10.4 4- 1.1 Ma, late Mid-Miocene (Serravallian), for the lavas, which are currently the best data available and have not been questioned by later workers. It is possible that the centre of this igneous activity is related to the Yermak plateau (hot spot) all of which heralded the uplift of Spitsbergen and the Barents shelf especially at its northwest corner (see Chapter 21).

8.2

Mesozoic, Permian and Carboniferous cover

The somewhat artificial southern boundary of the sector in this chapter is taken at a stratigraphic level rather than a simple boundary. The overlying strata to the south are described as for the Central Basin in Chapter 4 and comprise the following: Nordenski61d Land Supergroup (with Triassic strata) Bfinsow Land Supergroup (Permian, Carboniferous and latest Devonian). It is indeed the cover sequence from Paleogene down to latest Devonian or Early Carboniferous strata.

8.2.1

Basal Biinsow Land Supergroup unconformity and outliers

The southern boundary of the pre-Carboniferous Terranes is essentially the unconformable cover sequence of the Central Basin. Being subhorizontal in a glaciated terrain of mountains and nunataks the cover strata appear as outliers to the north before the unconformity dips south below ice and then sea level where the

NORTHWESTERN SPITSBERGEN terrane is entirely of the cover sequence. The cover sequence is described in Chapter 4 and the boundary of this study area is thus a punctuated transition.

8.2.2

Lamprophyres at Krosspynten

Monchiquite (lamprophyre) dykes cut Keltiefjellet division strata (of the Wood Bay Formation). They are conspicuous rocks with large biotite crystals. This cross-cutting relationship indicates a post Early Devonian age which cannot be further constrained by direct stratigraphic relationships. However, an age of 309 + 5 M a by K Ar dating of biotites suggests a Moscovian (mid-Mississippian) emplacement (Gayer et al. 1966, item 76). They appear to be of a generation later than the lamprophyres associated with the late tectonic plutons of N y Friesland which may be early Devonian. The dykes are variable in structure, trending N-S, and thickness not exceeding 2 m. They occur immediately west of the Billefjorden Fault Zone and show some increasing shear structure, with calcite veining, towards it. From specimens CSE collected, 1957-9, J. C. Rucklidge, D. G. Gee with S. O. Agrell noted a fine-grained to glassy green rock (?analcite) with phenocrysts of biotite and xenoliths (some igneous some quartzitic) up to 12cm across and xenocrysts of biotite and pyroxene. Leucocratic ocelli, largely of calcite, suggested amygdaloidal texture. All in all it was concluded from a ghost olivine that a magma of olivinedolerite composition with xenoliths originating in the lower crust (or mantle) had been altered after emplacement by hydrothermal activity in an extensive regime. The titanaugite cores in zoned crystals were out of equilibrium in relation to the final crystallization.

8.3

Liefde Bay Supergroup

Nordenski61d (1866, 1867) included the Devonian strata of N o r t h Spitsbergen within his Hecla Hoek Formation as Red Beach Strata. However, in 1875 he used the name Liefde Bay Formation for these rocks to distinguish them from the Hecla Hoek to the east which he assumed to be Silurian (Kulling 1934, p. 166). Following Nathorst (in Suess 1988) the rocks (as outlined on his map in fig. 2.1) commonly referred to as Old Red Sandstone are thus properly named the Liefde Bay Supergroup. This is defined as comprising the Andr6e Land Group, the Red Bay Group and the Siktefjellet Group. The oldest of these three groups is neither typical 'Old Red' facies nor necessarily Devonian, hence the advantage of a distinct name for the whole package. With the exceptions of the Marietoppen Formation, north and south of Hornsund, and the Roedvika Formation of Bjornoya, the outcrop of the Liefde Bay Supergroup, or indeed Devonian rocks in Svalbard, is confined to northwestern Spitsbergen. The Liefde Bay Supergroup has an estimated maximum stratigraphic thickness of c. 8000 m which comprises three groups as follows. The Andr~e Land Group consists of Mid-Devonian Wijde Bay, and Grey Hoek formations and the Early Devonian Wood Bay Formation. The Mimer Valley Formation is in part a lateral equivalent in the southeast of the area to the above formations, although it continued into Late Devonian time. The group lies unconformably on the Red Bay Group. The Red Bay Group (2500 m) of Early Devonian age comprises the Ben Nevis, Framkelryggen, Andr~ebreen mainly sandstone formations, and the Rivieratoppen (conglomerate) Formation. This group unconformably overlies the Siktefjellet Group and overlaps onto metamorphic basement rocks. The Siktefjellet Group (4500 m + ) of ?late Silurian and/or Early Devonian age consists of the Albertbreen (sandstone) Formation the Lilljeborgfjellet (conglomerate) Formation and the Rabotpasset (conglomerate) Formation. Both conglomerates rest unconformably on metamorphic basement rocks. The Liefde Bay Supergroup facies are fluviatile and marginal marine molasse type deposits following the main phase of the Ny Friesland (Caledonian) Orogeny in Svalbard and the H a a k o n i a n

135

diastrophism. They were affected by earliest Devonian (Haakonian), Early Devonian (Monacobreen Phase) and Late Devonian (Svalbardian) tectonic activity separated by a time of relatively stable sedimentary environment. The Svalbardian movements closed the Caledonian episode. This completed the Basement structure. It was succeeded by the latest Devonian sediments that initiated the cover sequence and belong to the Billefjorden Group of the succeeding Btinsow Land Supergroup. The strata occupy a N-S-trending half-graben, bounded on the east by the Billefjorden Fault Zone, where the youngest rocks occur and the bottom is not seen, and to the west by a narrow horstgraben structure and then by basement rocks overlain unconformably, and repeated in a further zone by faulting. The net dip is thus eastwards. Figure 8.2 summarizes the stratigraphy and nomenclature of the Liefde Bay Supergroup. The names introduced in this work are from Friend et al. (1997), and explained briefly below.

Liefde Bay Supergp From Liefde Bay System of Nordenski61d (1875), as mapped (Nathorst in Suess 1888), the supergroup now refers to all the Old Red Sandstone rocks, of whatever facies, comprising three groups: Andr6e Land with Marietoppen Fro, Red Bay, and Siktefjellet. The Andr~ebreen (sandstone) Fm is redefined in two respects: (a) south of Liefdefjorden the large outcrop mapped as Siktefjellet sandstone by Gee & Moody-Stuart (1966) has been shown to be an extension of the Andr6ebreen Formation by Gjelsvik & Ilyes (1991); (b) further fieldwork by the Cambridge Group (Friend et al. 1997) described the original formation north of Wijdefjorden as comprising three members: Buchananhalvoya,

Princess Alicefjellet and Rabotdalen. Rivieratoppen (conglomerate)Fm. This name is introduced in place of Red Bay conglomerate partly because the name Red Bay is also used for the group that contains it and partly because until 1966 Red Bay Conglomerates included the conglomerates of the Siktefjellet Group as well. It has been redescribed as comprising the Wulffberget (marble conglomerate) Member and the Konglomeratodden Member (Friend et al. 1997). The name was mentioned in a similar sense, but not defined by Mokin & Kolesnick (1996). Albertbreen (sandstone) Fm. This is renamed from the Siktefjellet Sandstone Formation of Gee & Moody Stuart. Firstly, because Siktefjellet has been used for the group which includes this unit and secondly, because the Siktefjellet Sandstone as originally defined now appears to belong to two distinct groups- the northern (type) outcrop in Siktefjellet being of the original Siktefjellet Group and that south of Liefdefjorden belonging to the Red Bay Group being most nearly correlated with the Andr6ebreen Sandstone. Rabotpasset (conglomerate) Member was separated as an older more indurated basement breccia unit from the Lilleborgfjellet Formation (Friend et al. 1997). Friend et al. (1997) stratigraphy was based on field work in 1992 and earlier, and mostly north of Liefdefjorden. Since then the Red Bay Group strata south Liefdefjorden have been investigated by A. McCann working with the Norsk Polarinstitutt (pers. comm.) with further nomenclature which is introduced in Section 8.3.2 and is likely to be accepted by SKS. Observations at the southern margin of the main Devonian outcrop were made in Ekmanfjorden (Dineley 1960) and at Lykta (Birkenmajer 1965).

8.3.1

Andr~e Land Group

The Wijde Bay, Grey Hoek and Wood Bay formations were identified and described by Holtedahl (1914a, b, 1926). The Mimer Valley succession was first described by Vogt (1938, 1941) and by Friend (1961). For a time the latter were given group rank (Allen, Dineley & Friend 1967; Friend 1973 and Murashov & Mokin 1976, 1979), although Harland e t al. (1974) introduced the Andr6e Land Group which now contains the above units and the Mimer Valley strata reduced to formation and member ranks as shown in Fig. 8.2.

Mimer Valley Formation. Known from the detailed palaeontological research of Stensi6 1918a, who listed many beds with vertebrate remains, the unit was recognized and described by Vogt (1938, 1941) and Friend (1961) who systematized the named units.

136

CHAPTER 8

GROUP BILLEFJORDEN

NW ,

I

ANDRleE LAND

BBF

I

SE (Mimerdalen)

AGE

I

Tournaisian Famennian

HORBYEBREEN FM

ORUSTDALEN FM

SVALBARDIAN DIASTROPHISM

MIMER VALLEY WIJDE BAY FM (500-600 m) GREY

ANDREE

FM

LAND

(13001400 m)

3

Estheriahaugen Mbr (100 m) Eifelian

Gjelsvikfjellet Mbr (300 m)

Stj~rdalen Division

GROUP

n

D Frasnian

Givetian

FM

Forkdalen Mbr (630 m) Tavlefjellet Mbr (300 m)

HOEK

Plantekl~fta Mbr (100__m~_ __ Planteryggen Mbr(100 m) Fiskekl~fta Mbr (130 m.)_ __

D

Emsian

BBF

0

n,

(.9

WOOD

n,

U.I 13_ Z) CO

--..........~eltiefjellet, Lykta Division Skjoldkollen ~ ' ~ ~Vaktaren ~.~ (green) Mbr

BAY FM

Austfjerden (sandstone) Mbr

Kapp Kjeldsen Division

(2900+ m) O r s a ~

(SE)

Pragian

D l

M

Q3

y

BBF I

MONACOBREEN DIASTROPHISM LIJ D U_ ILl _1

(NW)

BEN NEVIS FM (900 m)

BBF

I

FR/ENKELRYGGEN FM (600-750 m) RED BAY GROUP

Buchananhalveya Mbr (700 m)(~qq ANDRleEBREEN . . . . . . . FM Princesse Alicefjellet Mbr (500 m) (1400 m)

Rabotdalen Mbr (200 m)

RIVIERATOPPEN FM (500-7(~ m)

SIKTE-

ALBERTBREEN FM

Wulffberget Mbr Konglomeratodden Mbr (3050-1400

Lower part of succession not exposed in the east

Lochkovian

?D

m) (~

?S

FJELLET

LILLJEBORGFJELLET FM (100-400 m)

GROUP RABOTPASSET FM

(?100 m) @

?S

SMEERENBURGIAN TECTOGENESIS KROSSFJORDEN GROUP

BASEMENT

Fig. 8.2. Liefde Bay Supergroup units with tectonic events and age estimates on the right.

Proterozoic

NORTHWESTERN SPITSBERGEN The formation occurs only in Dickson Land (the southeast of the northwest sector), the type section in Mimerdalen is at its eastern margin. Further west the units have not been systematically distinguished because facies vary considerably; although they are distinct from the (red coloured) Wood Bay Formation on which they rest. The faunal assemblage of the Mimer Valley Formation is rich in fish (Heterostraci, Acanthodii Arthrodira, Antiarchi, Crossopterygii and Actinopterygii), ostrocodes and conchostracans. The flora includes plant assemblages and many species of miospores (the Emsian/Eifelian Eximus and the Lochkovian Triangulatus assemblages of Allen (1967, 1973). Four members were distinguished. Planteklnfta Conglomerate Mbr, 100m is bed (m) of Stensi6 (1918a) and Plant Ravine Conglomerate (bed 9) of Vogt 1941. The member consists of pebble conglomerates with boulders up to 35 cm diam. consisting of grey (Devonian?) sandstone and some siltstone. The matrix is grey sandstone and beds of shale with ironstone concretions interbedded with plant-bearing dark green sandstones. Murashov & Mokin (1979) observed the conglomerate resting on different divisions of the Planteryggen (sandstone) Member. They also suggested that the units may be Early Carboniferous on the basis of lycopod remains. However, this review follows Allen (1967) in opining a Mid-Devonian (Givetian) or even early Frasnian (Late Devonian) age from palynomorphs. Planteryggen Sandstone Member, is Stensi6's bed (1) and Vogt's (1941) bed (8), who estimated a thickness of 400 m. It was named by Friend (1961) and consists of multicoloured sandstones and green shales. The uppermost 40 m are composed of red conglomerate with pebbles of quartzite, sandstone and siltstone. The basal sandstone is of sugary texture with large tree trunk fragments. Hoeg (1942), on the basis of plant remains suggested a mid- or Late Devonian age in contrast to Murashov & Mokin (1979) who preferred a later age, i.e. Famennian. Fiskeklofta Mbr, 115 to 145m contains Stensi6's Schiefer der Fischschlucht and other beds (1918a) and Vogt's (1941) beds 6 and 7. The sedimentary succession comprises 100m of green argillaceous sandstone and overlies brown and black shale. Flat ironstone concretions occur throughout and conformably overlie the Estheriahaugen Member. Westoll (1951), Halstead (1969) and Halstead-Tarlo (1973) considered the vertebrate fauna to be Late Givetian which is the strongest evidence for the age of any part of the formation. Vigran (1964), Allen (1967) and Murashov & Mokin (1979) discussed the age with less discriminating material. Estheriahaugen Mbr, 90-130 m in Stensi6's 5K1 to F2 and possibly his bed (e) (1918a) and includes Vogt's (1941) beds (1 5). The member is composed of light and yellowish grey polymictic, quartzitic sandstones interbedded with black shales and ironstone concretions. The lower part consists of shales. Cannel coals and pyrite nodules occur in the mudstones and upper sandstones. The lower contact with the Wood Bay Formation is c o n c o r d a n t whether conformable or tectonic. Spores suggest Givetian to Eifelian age. The lowest division (Vogt's bed 1?) has the Eximus spore assemblage indicating Emsian-Eifelian age. The Triangulatus spore assemblage follows Vogt's bed 1? (Allen 1967). Overall there is a contrast between the eastern and the western to northwestern development. It was formed in fresh water fluvial and lacustrine environments with cannel coal in Mimerdalen (Horn 1941) and oolitic ironstone (Friend pers. comm.) with periodic build-out of delta lobes towards deeper brackish water in the north west. Wijde Bay Formation, 500-600 m (Holtedahl 1914a; Friend 1961). At the top of the succession in Andr6e Land, 500-600 m of light coloured sandstones with siltstones and shales comprise the Wijde Bay Formation. Murashov & Mokin (1979) referred to it as a group with the Tage Nilsson Formation as its only constituent. The base is marked by the appearance of pale quartzitic sandstones interbedded with massive grey fossiliferous siltstone and black shales. Magnetite/hematite occur in joints. The light colour and increased proportions of sandstone distinguish the formation from that below. Fish faunas indicate a Late Mid-Devonian (Late Eifelian~Givetian) age (Nilsson 1941; Foyn & Heintz 1943; Murashov & Mokin 1979). The combined marine molluscan and non-marine fauna suggests a coastal, intertidal, partly brackish water environment. A build-out of sediments into the sea in a NNE direction is suggested. Grey Hoek Formation (c. 1000m). Holtedahl (1914a); Friend (1961), Friend et al. (1966); Murashov & Mokin (1979) originally gave the Grey Hoek unit group status and divided it into three formations which are reduced here to members:

137

Forkdalen Member Tavlefjellet Member and Gjelsvikfjellet Member Skamdalen Division Verdalen Division The Grey Hoek Formation succession consists of dark grey and black siltstones and sandy shales with intercalations of paler grey to green quartzites and dark shelly limestone bands. The lower part may be coarser and lighter in colour. The top is seen by a change of colour to the lighter sequence of the Wijde Bay Formation and the base is at the contrast with the, predominantly red, Wood Bay Formation. The stratigraphic thickness is difficult to determine because of strong folding and lack of marker horizons. Foyn & Heintz (1943) estimated 1000m. Worsley (1972) described the sequence in detail as follows: silty horizons have ripple tops with plant debris in the troughs. Desiccation cracks are abundant locally, as are slump structures and intraformational shales. Nucula sp. assemblages occur with both valves articulated. Massive coarse-grained sandstones have some mud-flake conglomerates at their base and become finer and better sorted upwards. Sandstones exhibit sole structures, sole marks, and cross-bedding, some horizons show slumping. The formation has yielded fish (Lunaspis, Homostius, Heterostius, Porolepis), bivalves, gastropods, ostractodes, trace fossils (Chondrites) and plants including charophytes. With the possible exception of the earlier part of the Gjelsvikfjellet Member (Emsian), fish and bivalve faunas indicate that the Grey Hoek Formation is Eifelian (Quensted 1926; Heintz 1937; Foyn & Heintz 1943; Orvig 1969; Murashov & Mokin 1979). Friend (1961) suggested formation in a marginal marine environment, whereas Worsley (1972) preferred fluvial action in a broad coastal swamp with shallow lagoons. Palaeocurrents (based on sole structures and crossbeddings) indicated predominant flow to the NE and NNE; but with some steeply folded strata there is some doubt. Forkdalen Mbr, 630m of grey and dark grey siltstones, mudstones and polymict sandstones with large carbonate nodules up to 1 m diam. Tavlefjellet Mbr, 300m. The upper part consists of dark grey to black calcareous mudstones with bands of silty carbonaceous nodules up to 0.5m diana. The lower 170m is dark grey to black shaly mudstones with 2 to 3 m bands of lighter calcareous siltstones/silty limestones with carbonate nodules up to 10m in diam. Gjelsvikfjellet Mbr, 60-200 m is formed of two divisions (beds) (members of Murashov & Mokin 1979) which contain almost identical fish assemblages suggesting coeval deposition of different facies. They reported that the upper Skamdalen division, of dark grey, micaceous, calcareous siltstones with black calcareous mudstones at the base rests unconformably on the Verdalen Beds in Andr~e Land and on red beds of the Stjordalen Beds of the Wood Bay Formation in north Dickson Land. The Verdalen division (0-100 m) was considered by Friend et al. (1966) to belong to the Wood Bay Formation. It consists of multicoloured silty limestones. Soft sediment sliding eastwards at Straumtangen on Wijdefjorden has been noted (Horowics 1992). Wood Bay Formation, 3000m, was defined by Holtedahl (1914a) and further described with its constituent parts by Friend (1961, 1965), Moody Stuart (1966) and Friend & Moody Stuart (1972) (Fig. 8.3). This is the main red bed unit of the Liefde Bay Supergroup and has a relatively uniform appearance with upward fining cyclic sandstone siltstone

Fig. 8.3. Faunal divisions and lithological members of the Wood Bay Formation (after Friend & Moody-Stuart 1972).

138

CHAPTER 8

facies and so is difficult to subdivide or to correlate divisions in the field. It is not therefore appropriate to refer to it as a group as did Murashov & Mokin (1979). Five distinct but impersistent facies occur within the dominant red siltstone lithology as illustrated in Fig. 8.3 and have been given member status (Friend et al. 1966). (i) The Verdalen (carbonate) Mbr has been already referred to. It consists of 30 to 40m of yellow and grey limestones and calcareous sandstone. On lithological grounds rather than on age it is reasonable to associate these strata with the Wood Bay Formation. (ii) The Skjoldkollen (carbonate) Mbr occurs locally in the north 100m above the top of the Kapp Kjeldsen faunal division. It is a 40 m thick unit, extending 8 km laterally, with 5 m thick green marlstone cyclothems. (if) The Vaktaren (green) Mbr (the 'Pale Beds' of Foyn & Heintz 1943) occurs at the top of the Kapp Kjeldsen division and extends 15 km laterally. (iv) The Orsabreen (green) Mbr is 600 m below the Vaktaren Member. Both these units are examples of colour-distinct units apparently due mainly to local reduction of iron. (v) The Austfjorden (sandstone) Mbr is a dominantly sandstone facies. It is non-cyclic, grey, green or yellow coloured and occurs mainly in the southeast, passing westwards into typical red beds with silty cyclothems. These five local facies variants do not add up to more than a minor part of the bulk of the formation. On the other hand three divisions, proposed by Foyn & Heintz (1943) and followed by Murashov & Mokin (1979) are faunally but not easily lithologically distinguishable. Though difficult to define precisely or to see at a glance they do constitute the whole of the formation and are more useful for general analysis of the stratigraphy. It is arguable that they should constitute the formal members of the formation if they are distinguished by observable biostratigraphic characters. According to the principle of rock, lithic or local units any observable characters whether colour, composition, elasticity or easily observable fossils may characterize a lithic unit if recognizable in the field. This question is left open. If they are members then the 'members' (i)-(v) above would become beds. Lamar & Douglass (1995), from detailed mapping southeast of Austfjorden, distinguished these three divisions lithologically in the Austfjorden sandstone facies, but did not demonstrate that their sedimentological criteria match the faunal divisions elsewhere. The Stjordalen Division is 400m thick in the north and thins to 50m southwards. The upper boundary being the sharp change to the grey-black beds of the Grey Hoek Formation, and locally the base of the Verdalen Member. The lower boundary is marked by the change from red mudstones and calcareous siltstones with pelletoid structure and has variable but distinct characteristics. The lower boundary is characterized by nectaspids, monaspids, osteostracans, arthrodirans and crossopterygians. The most probable age is Emsian (Murashov & Mokin 1979). The Keltiefjellet or Lykta division (600-900 m) generally comprises coarser grained sediments and thus not so red. It is rich in fossil fish with Doryaspis nathorsti, Arctolepis; but Gigantaspis; and small species of Doryaspis are absent. Fish and plants indicate a Pragian (Siegenian) age. The name Keltiefjellet was proposed by Foyn & Heintz (1943) and was renamed Lykta by Friend et al. (1966) on the basis of the current lithostratigraphic code. It was adapted by Murashov & Mokin (1979) as a formation. The Kapp Kjeldsen division (1000-1500 m) the top of which is marked by the 'pale beds', and the bottom by the change to the grey red rocks of the Ben Nevis Formation. This division is mainly composed of coarse-grained, greenish grey and yellow, cross-bedded and massive, micaceous sandstones and sandy siltstones with lenses and bands of grit and fine pebble conglomerates. The sands and sandy silts pass eastwards into the Austfjorden (sandstone) Mbr with an associated decrease in fossil fish and an increase in plant remains. The division is characterized by Gigantaspis, Arctaspis and small species of Doryaspis and near the top by Doryaspis nathorsti. These suggest a Pragian (Siegenian) age (Murashov & Mokin 1979) although ostracods and miospores indicate a wider age range, extending later to Emsian and Eifelian. The Sigurdfjellet Division was added on faunistic grounds at the base by Goujet (1984). Lamar & Douglass (1995) mapped an area SW of Austfjorden. They described the Wood Bay strata in the above three divisions (their formations) and showed that the Kapp Kjeldsen unit was dominated by channel deposits; Keltiefjellet by minor channel and major lev6e and floodplain sediment; and the Stjordalen without channel deposits. These characteristics may be local and all within Friend's (1965) Austfjorden (sandstone) Member. The original divisions were defined palaeontologically. It remains to be seen to

what extent the Wood Bay Formation is more conveniently divided by these three or four members with the facies variations as beds or vice versa. More significant perhaps is their isopach evidence of thinning of the Keltiefjellet unit from 1600 to 200 m towards Austfjorden, over a distance of little over 8 km. Crusiana are found throughout the t w o lower divisions and Lingula are only found in the Stjordalen division at one locality. Their presence suggests a marine influence. In the southwest (near the mountain Pretender) the Lykta division overlaps the Kapp Kjeldsen division to rest directly on Pre-Devonian metamorphic rocks, whereas to the northwest it rests conformably on the Kapp Kjeldsen division which in turn rests unconformably on the Red Bay strata. Friend & Moody Stuart (1972) suggested an intermontane flood plain environment for the Wood Bay Formation with marine incursions. In the southwest corner of the outcrop the red colour and carbonate concretions (calcretes also reported by Reed 1991) suggest a situation above the water table. It was argued to represent only part of the original basin, truncated by sinistral strike-slip along the Billefjorden Fault Zones (Harland 1969; Friend 1981). Three river systems have been distinguished in the formation and their interpretation is considered in Chapter 16. McCann (1996) demonstrated that the Wood Bay Formation unconformably oversteps in the southwest of the Biskayerfonna-Holtedahlfonna anticline in which Red Bay Group strata are folded (his Monacobreen Phase Diastrophism). A sedimentary transition had long been suggested first by Hoel (1914) south of Liefdefjorden, and at Sigurdfjellet and a third locality was added by Foyn & Heintz (1943) west of Bockfjorden. They wrote (p. 20) 'It is, however, only on Vonbreen (= Hoffnung Glacier) south of Sigurdfjellet that we can state with certainty that the Red Bay Series is normally covered by the Wood Bay Series'. Details of the critical strata were given in which at the base of the Kapp Kjeldsen Division are red sandstones resting conformably on greyish green sandstones with layers of quartz conglomerates at the top. The red beds bear distinctive pteraspids with some Doryaspis characters and other forms which could relate to Ben Nevis or Kapp Kjeldsen forms. The grey beds with fewer fossils include a small Pteraspis and Homaspis which are key elements in the Ben Nevis fauna. These critical units (referred to here as the Vonbreen sandstones) are east of the BBF. It thus seems that the Monacobreen folding may have been confined within the Biskayerfonna-Holtedahlfonna terrane and so reinforces the idea that the antiform may be the product of renewed transpression within that terrane (see Section 8.5.4).

8.3.2

The Red Bay Group ( N o r d e n s k i 6 1 d 1892; H o l t e d a h l 1914a)

This g r o u p is restricted at the surface to the west o f the half-graben (west o f the B r e i b o g e n F a u l t ) w h e r e it rests u n c o n f o r m a b l y o n either the Siktefjellet G r o u p or overlaps o n t o the m e t a m o r p h i c b a s e m e n t . T h e c o n g l o m e r a t e is its m o s t distinctive facies, a n d this was first r e c o r d e d by N o r d e n s k i 6 1 d (1892) in R a u d f j o r d e n a n d defined by H o l t e d a h l (1914a et seq.) (see Fig. 8.4). A. McCann (pers. comm.) has suggested that the conglomeratic sandstones, east of the Biskayerfonna-Holtedahlfonna metamorphic (Krossfjorden Group) horst, could be younger than the typical Ben Nevis Formation. Until the case has been demonstrated for an unconformable relationship above the Ben Nevis Formation they may provisionally be regarded as informal conglomeratic members of that formation. They are, west of the Breibogen Fault, the Fotkoilen sandstones and Lihallet conglomerates north of Liefdefjorden and Brottfjellet and Germaniabekken conglomerates south of Liefdefjorden. However, if significantly younger they might be members of a new formation between the Wood Bay and Ben Nevis formations. This however would appear to conflict with the evidence from the Vonbreen sandstones referred to above. The Ben Nevis Formation, 900 m (Kiaer 1916; Friend et al. 1966) consists of resistant grey-green, cross-bedded, polymict sandstones with grit, siltstone and argillite intercalations. A Late Lockhovian (Gedinnian) to Early Pragian (Siegenian) age has been determined from fish faunas (Heintz 1929; Vogt 1938; White 1956). The Fr~nkelryggen Formation, 600 750 m (Kiaer 1916; Friend 1961) of predominantly red beds is finer grained and more fissile than the Ben Nevis Formation. The red feldspathic sandstones and siltstones contain six intraclast conglomerate horizons rich in fish plates (Kiaer & Heintz 1935).

NORTHWESTERN SPITSBERGEN

139

Fig. 8.4. Geological map of the Raudfjorden/Liefdefjorden area, northwestern Spitsbergen, showing the distribution of the Siktefjellet and Red Bay groups (with permission of Cambridge University Press from Friend, Harland, Rogers, Shape & Thornley 1997).

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There is a welded tuff near the base (Murashov, Pchelina & Semebskiy 1983). An abundant fish fauna indicates a Lockhovian age (Blieck 1983). The Andr~ebreen (sandstone) Formation (Holtedahl 1914a; Friend 1961; Friend et al. 1997). The limitation of Friend's (1961) Formation by Murashov & Mokin (1979) to what is its top member is not followed here. Then formations are taken here as members of the original Andr6ebreen Formation. They stated that the lowest fossil horizon is located at the base of the Fr~enkelryggen Formation (apart from some plant remains) and the Andr+ebreen sandstone was thought to be fossil-free (Kiaer & Heintz 1935; Friend 1961; Blieck, Gonjet & Janvier 1987). However, Gjelsvik & Ilyes (1991) pointed out that the lowest P s a m m o s t e u s horizon is located on the Fr~enkelryggen ridge 550 m above sea level in a yellow-green sandstone of the Andr6ebreen Formation and well below the base of the Fr~enkelryggen Formation (Gee pers. comm.). This is significant because the 'Siktefjellet Sandstone' as mapped by Gee & Moody-Stuart (1966) south of Liefdefjorden, from paleontological evidence could be coeval and, with similar lithology should be considered a part of Andr6ebreen (sandstone) Formation. The matter is under investigation by Gjelsvik and Ilyes and their proposals regarding nomenclature are awaited. Friend et al. (1997) reinvestigated the Raudfjorden area and divided the formation north of Liefdefjorden into three members. Buchananhalvoya (sandstone) Mbr, 700 m (Friend et al. 1997) north of Liefdefjorden. This member is exposed throughout much of Buchananhalvoya as well as north of Andr~ebreen and is provisionally taken to include the main outcrops south of Liefdefjorden. It consists mainly of grey-green fine to medium-grained sandstone with occasional coarse sandstones and small pebbles. To the north the member interdigitates with the Princesse Alice Member and interbeds of conglomerates appear and thicken to the north. Thin (cm to dm) interbeds of dark-grey mudstones occur. The sandstones may be divided into sheet units up to several m thick with common ripple migration and cross-bedding. The sandstones contrast with those of the Siktefjellet Group below, not only because of a marked contrast in attitude of the strata, but also because of the greater abundance of potash feldspars and plagioclase in the Siktefjellet Group. The Buchananhalvoya sandstones carry little feldspar except near the Raudfjorden Fault at the head of Liefdefjorden. Princesse Alicefjellet (conglomerate) Mbr, 500 m (Murashov & Mokin 1979, Friend et al. 1997). This conglomerate contains clasts of red vein quartz, pink and green quartzite and quartz-mica schists It is a lateral equivalent of the Buchananhalvoya Member with which it interdigitates. It is interpreted as deposits of a river system alongside that forming the Buchanenhalvoya deposits to the south but depositing a uniform quartz-pebble breccia interbedded with pebbly sandstones. It is characteristically red but locally yellow or grey. The clasts rarely exceed 5 cm but occasionally reach 15 cm. Vein quartz and psammite constitute 60 90% of clasts with subordinate mica schists, gneiss and carbonate. However, the carbonate clast content increases towards the base near the marble rich Rivieratoppen Formation. The change in clast composition upwards suggests erosion by flash floods of mountainous terrane in which a marble cover was eroded into underlying quartzose strata. Rabotdalen (mudstone) Mbr, 200m. This member is poorly exposed and represents an interval between two conglomerate members (Gee & MoodyStuart 1966) and was recognized by Murashov & Mokin (1979) who estimated its thickness. In the stratigraphic scheme here it underlies the Princess Alice Member and overlies the Wulfberget (marble conglomerate) Member of the Rivieratoppen Formation. Friend et al. established a thickness of between 30 and a maximum of 100m. It does not crop out further south beneath the Buchananhalvoya Member. Known from float it is a fine dark grey, yellow weathering slabby mudstone which alternates with coarse siltsones. The facies appears to be similar to that occurring between conglomerate units within the Rivieratoppen conglomerates. A lake basin environment within the river systems is suggested. South of Liefdefjorden is the outcrop east of the metamorphic horst and west of the Breibogen Fault which was first included in the Siktefjellet Group by Gee & Moody-Stuart (1966) and then shown by Gjelsvik & Ilyes (1991) to be coeval with the Andr6ebreen Formation, but of distinctive facies. This member needs a distinct name. Provisionally it is included in the Buchananhalvoya Member. Gjelsvik & Ilyes (1991) noted that 'peloid'-carbonate conglomerate lenses within the sandstones contain a rich Lochkovian fossil fauna including four orders of fish (including Heterostraci, Placodermi, Acanthodii etc.) in addition to ostracodes, echinoderms, bivalves and gastropods. These strata thus contained the then earliest biostratigraphic evidence of Devonian age.

This marine component indicates a tidal basin mixing a variety of material of different origins. In the main Devonian trough, west of the horst and south of Liefdefjorden, McCann (pers. comm.) found that above the Wulffberget conglomerates the main body of the Red Bay Group is of two facies: the Smgtbreen (sandstone) and the Schivefjellet (conglomerate) members appear to make up his Wideroefjella Formation. This may be coeval with most of the three upper formations of the group. The Rivieratoppen (conglomerate) Formation (Friend et al. 1997). This formation represents the original Red Bay Conglomerate which name has been adopted for the group and which conglomerates also included those in the Siktefjellet Group. It is conspicuous in the eponymous pale coloured cliffs on both sides of Raudfjorden as seen on entering the fjord from the north. Exceptionally fine exposures are seen at Rivieratoppen and Konglomeratodden in Raudfjorden, in the islands of Liefdefjorden and on its north coast near the glacier and moraine of Erikbreen and in the cliffs of Wulffberget west of Hannabreen. Ilyes, Ohta & Guddingsmo (1995) reported heterostracans, both cyathaspidids and pteraspidids in the WulWoerget Member of the Rivieratoppen Formation in Hestekoholmen, the horse-shoe shaped island offshore Hannabreen in Liefdefjorden. Apart from the interest of this earliest fish record this confirms that the whole of the Red Bay Group is Early Devonian, and in this occurrence Lochkovian. Wulffberget (marble conglomerate) Mbr, 30-100m (Murashov & Mokin 1979; Friend et al. 1997) comprises red conglomerates containing large clasts of metamorphic basement rocks, notably marbles. Indeed the source rocks would often appear to correspond with the immediately underlying rocks. It exhibits a thick reddish colouring due to weathering of the marbles and the interstitial material. This member would seem to have local or southerly provenance from the distribution of marble in the basement. Neither granite nor migmatite clasts were observed (Harland 1961) except locally in the underlying member. Contacts with the basement may expose a transition from solid marble through marble with irregular veins of overlying sediment, through shattered marbles still retaining an original orientation, to irregular disoriented breccia with large and small clasts, to a coarse boulder breccia and upwards into a subrounded monomict conglomerate. Although the first appearance of the conglomerates suggests a massive hardly stratified rock, closer inspection reveals discrete units ranging from less than 1 m to about 10m in thickness. The distinction varies and can be due to changes in clast size, composition, general texture, matrix composition or a combination of the above. The typical Wulffberget lithology is of pebble- to boulder-grade clasts of subrounded, often monomict marble. The genesis of the conglomerate with such large boulders must have been local and often by cohesive bulk transport. Megaclasts up to 4 m have been observed and rafts of coherent structure seem to have been carried along. Transport is unlikely to have exceeded 2 or 3 km and the implication is of erosion from extensive and intermittent fault scarps. Manby & Lyberis (1992) figured Rivieratoppen with very large slabs and blocks seemingly cascading down the cliff face but within the conglomerate. Transport again must have been from a quite local scarp. Although the conglomerate constituents cannot have travelled far, they are extraordinarily widespread, not only through the length of the Biskayerfonna-Holtedahlfonna horst but also to the west of the Raudfjorden Fault in the islands of Kongsfjorden and the mainland to the north. This may be further evidence adduced for only one (Silurian) tectogenesis of the basement in that the upper marble formations had retained their superior stratigraphic position. Konglomeratodden (polymict conglomerate) Mbr, 180 m (Friend et al. 1997). Whereas the Wullfberget conglomerate often rests locally on Caledonian basement there is an underlying facies of polymict conglomerate seen at Konglomeratodden, the northern cliffs of Rivieratoppen, at Frankelryggen and overlying Siktefjellet grey sandstones (Albertbreen Formation) west of Siktefjellet. Both mass flow and fluvial genesis have been interpreted for the discrete sheets.

8.3.3

Siktefjellet Group

N o r d e n s k i 6 1 d (1892) first n o t e d c o n g l o m e r a t e s (in his H e c l a H o e k F o r m a t i o n ) in the n o r t h w e s t : H o l t e d a h l (1914, 1926) r e p o r t e d a n d t h e n set u p the O l d R e d S a n d s t o n e f o r m a t i o n s characterized by c o n g l o m e r a t e s a n d s a n d s t o n e s . T h e r e the m a t t e r rested (e.g. F o y n

NORTHWESTERN SPITSBERGEN & Heintz 1943; Friend 1961; Harland 1961) until Gee & MoodyStuart (1966) identified a significant unconformity within these rocks and distinguished an older group of sandstones and conglomerates as the Siktefjellet Group north of Liefdefjorden, especially at Siktefjellet. These older sandstones and conglomerates were more compacted and altered, less red, as well as being discordant with the overlying formations. The unconformity was held to represent a distinct diastrophic episode, which led Gee (1972) to name this 'Caledonian' event as Haakonian i.e. earlier than Svalbardian and later than Ny Friesland events in Svalbard. The age of the overlying Red Bay rocks are (earliest) Devonian, therefore the Siktefjellet rocks could be, in part at least, latest Silurian. Gee & Moody-Stuart (1966) defined the Siktefjellet Group as comprising two formations: the Siktefjellet sandstones (above) and the Lilijeborgfjellet conglomerate. In their map the conglomerate is confined to the outcrop north of Liefdefjorden but may occur on both sides of R a u d f j o r d e n - a convenient exposure being in Rabotdalen, of which a photograph by Holtedahl (1926, p. 1.2) confirms his inclusion of these conglomerates in his Red Bay Conglomerates. The sandstone described by Gee & Moody-Stuart (1966) is shown in a N-S-elongated outcrop south of Liefdefjorden as far as Bockfjorden. It is this outcrop which Gjelsvik & Ilyes (1991) suggested belongs to the Andr~ebreen Sandstone Formation of the Red Bay Group rather than to the Siktefjellet Group. They described these southern rocks as 'grey, grey green or occasionally yellow-green, tough and massive dm to m thick beds of fine to medium-grained sandstone', interpersed with up to 1 m thick lenses of quartzite chip conglomerates and frequent cross-bedding. The sandstones were compared in various aspects with those of the Siktefjellet outcrop. Mineralogically the northern facies had abundant potassium and plagioclase feldspars whereas to the south there was virtually no K-feldspar and little plagioclase. Lenses of peloid conglomerate or breccia in the southern rocks proved to be fossiliferous as noted above. The Siktefjellet Group was redescribed in three formations (Friend e t al. 1997) (Figs 8.4 & 8.5).

Albertbreen (sandstone) Formation (= Siktefjellet sandstone of Gee & Moody-Stuart 1966) north of Liefdefjorden as developed at the type locality

141

Siktefjellet and distinguished from Red Bay rocks by Gee & MoodyStuart (1966) and Gjelsvick & Ilyes (1992). The formation's outcrop area is limited between the Rabotdalen and Breibogen faults and to the south by Liefdefjorden and is therefore only exposed at Siktefjellet, where it is thickest, and then northward at H6geloftet and Fr~enkelryggen after which the Rivieratoppen conglomerate rests directly on the Lilljeborgfjellet conglomerate. The formation is of grey-green fine to coarse polymict feldspar-bearing sandstone with local intercalations of black shale, grit and quartz conglomerates generally fining upwards and cross-bedded. Gee & MoodyStuart estimated 1400m at Siktefjellet whereas Murashov & Mokin (1979) estimated 350m and suggested an age of Lochkovian from plant remains; but to which outcrop these observations refer is not clear. Sandstones or siltstone units may be 20 m thick, the sandstones often being cross-bedded and the siltstones ripple-cross-laminated. Black mudstones are interbedded with the siltstones. Plant fragments occur but are indeterminate. Pebbly quartz sandstones with pebbles up to 1 cm occur. The bulk of the formation is interpreted as fluviatile sands deposited by braided river flow, with the finer deposits forming in overbank areas (Friend et al. 1997). Lilljeborgfjellet (conglomerate) Formation, 100-140 m (Holtedahl 1914a; Gee & Moody-Stuart 1966). This pebble conglomerate contains boulders up to 25 cm diam. of basement rocks including migmatite and gneiss. These include a distinctive garnetiferous quartzo-feldspathic augen-gneiss the source of which is possibly the metamorphic terrane west of the Raudfjorden Fault. The conglomerates (e.g. at Puddingen) show mixed clast composition in contrast to the dominantly marble conglomerate of the Rivieratoppen conglomerates. Gjelsvik (1991) described the conglomerates in detail in terms of clast provenance. In addition to those lithologies which matched the underlying basement and were generally of angular character suggesting only local transport, he noted a minor component of well rounded (fartravelled) quartz porphyry. After detailed comparison with known quartz porphyries in Svalbard (including those at Nordauslandet, Hornsund and Ny Friesland) he ruled them out as probable sources for various reasons. The source of these quartz porphyries remains unknown. If the travelled terrane concept of Harland & Wright (1979) is considered, it may explain why the quartz porphyry clasts cannot be correlated with known quartz porphyries in Svalbard as these areas would not have been juxtaposed then, as they are now. Rabotpasset (conglomerate) Formation (Friend et al. 1997). This unit, included in the Lilleborgfjellet Conglomerate by Gee & Moody-Stuart, was first noted as a distinct lithology by Holtedahl (1914). It was separated, as

Fig. 8.5. Schematic section showing the relationships between the units of the Siktefjellet and Red Bay groups (with permission of Cambridge University Press from Friend et al. 1997).

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here by Friend et al., on the basis that at two localities (the main one is located at Rabotpasset) the rocks are more deformed, more indurated, veined and contain a much larger component of local basement gneiss etc. than the overlying unit. The induration has the effect of making the whole rock look like basement because the clasts and matrix may not at first be easily distinguished. Higher up quartzose and micaeous psammites increase in abundance. It was further suggested that this unit may be separated from the overlying conglomerate by a minor tectonic phase.

8.4 8.4.1

The 'crystalline' rocks Early work

'Crystalline' rocks (in this sense comprising igneous and metamorphic rocks and formed in a medium- to high-temperature environment) of this sector were perhaps first recorded by Scoresby in 1820 and described by Durocher (1840-1850). They distinguished foliated granite, gneiss and unfoliated coarse-grained granite with transitional schists. On Nordenski61d's 1863 expedition, Blomstrand (1864) i.a. described the metamorphic rocks further south in Albert I Land. Nathorst (in Suess 1888) mapped all the crystalline rocks of the northwest sector as Archean and only the southern and eastern part of the Albert I Land High as Hecla Hoek. Further records by Drasche in 1874, Bryant in 1905, and Schetelig in 1912 are of a more detailed petrological nature. These rocks were believed to be ancient until the Isachsen expeditions of 1909 and 1910 and the Hoel-Staxrud expedition of 1911 gave opportunity for Hoel and Holtedahl to show that the northern granites and migmatites post-dated the metasediments. Thus Holtedahl (1914a, b, 1926) claimed the complex as Caledonian. At that time it was generally assumed (as Holtedahl did in Svalbard, and indeed was assumed in Norway) that the Caledonian Orogen comprised mostly Early Paleozoic strata rather than Precambrian. Schenk (1937) described the structure and petrology in more detail. A more recent interpretation of all these rocks was presented by Gee & Hjelle (1966), updated by Ohta (1969) and Hjelle (1979) with the results from continuing Norsk Polarinstitutt fieldwork. The tectonisation and metamorphism of most of the rocks of the northwest were long regarded as of mid-Paleozoic age, it was not until isotopic studies that this could be confirmed. A midPaleozoic age was established for both metamorphism and granitic intrusion (Gayer et al. 1966) but there was insufficient discrimination to establish a petrogenetic time-sequence. Smeerenburgian is a name for this sequence of events whatever their age. North of Liefdefjorden, the Biskayerfonna Horst, was mapped by Gee, and the range of petrologic types encouraged further isotopic dating studies (Ohta, Dallmeyer & Peucat 1989; Peucat et al. 1989; Dallmeyer, Peucat & Ohta 1990). South of Liefdefjorden the principal studies of the older rocks have been by Preston (1959) and Gjelsvik (1979). A suspicion has continued that some elements ofproto-basement may be subsumed within the Caledonian complex. A migmatite complex (the Kollerbreen zone), north of inner Kongsfjorden, was considered as a possible pre-Riphean basement as by Krasil'shchikov (1973) and possibly by Abakumov (1976, 1979). Ravich (1979) examined the Kollerbreen Formation with Abakumov east of Krossfjorden with K-Ar age determinations (430Ma and 380Ma) and concluded (with Holtedahl 1914, Gee & Hjelle 1966, Harland 1978 and others) that they were migmatized (Caledonian) Krossfjorden Group Riphean strata. However the Abakumov interpretation has persisted (e.g. Krasil'shchikov, Abakumov et al. 1996). Balashov et al. (1996), applying Rb-Sr and single grain zircon datings, confirmed mainly Caledonian ages as well as at least one inherited zircon. From a structural point of view the time sequence (not necessarily synchronous throughout the region for each phase) can be established thus: sedimentation then tectonization with metamorphism-migmatization, magmatic intrusions, batholithic emplacement. Although there is just one complex, a Caledonian

one with an older core, the youngest intrusions probably derived from the earlier migmatic and magmatic material. The Precambrian protolith has been reconnoitred throughout the sector and, to anticipate the conclusion here, a succession of three formations distinguished to the west of the Raudfjorden Fault namely Generalfjella (top), Signehamna, and Nissenfjella (Gee & Hjelle 1966) were combined in the Krossfjorden Group (Abakumov 1976; Harland 1985). They are interpreted here as the product of Smeerenburgian (Caledonian) migmatization etc. Their palaeosomes may represent pre-Nissenfjellet Formation units. East of the Raudfjorden Fault and north of Liefdefjorden. Gee (in Harland 1985) distinguished a similar sequence with marbles at the top. Gjelsvik (1979) traced the same marbles south of Liefdefjorden and correlated them with the Generalfjella Formation. Some revisions of Gee's informal nomenclature is necessary because two names should give way to prior named units. It is reasonable to extend the group name to include all these formations but for discussion of correlation (which must be uncertain) to keep east and west formations named distinctly as in Fig. 8.6. The allochthonous Richarddalen Complex is demonstrably older and a well established unit of proto-basement.

8.4.2

Magmatic intrusions

Hjelle (1979) described granitic rocks under three headings: (3) posttectonic red granite (i.e. the Hornemantoppen Batholith); (2) grey granite dykes; (1) weakly foliated granitic rocks. He also remarked that basic dykes are not seen to cut the granite.

(3) The Hornemantoppen Batholith (150 km 2) crops out in a NNW elongate pattern within the migmatite area. The most conspicuous facies is a coarse- to medium-grained red granite. It is a nonfoliated mass of monzonite composition, mostly equigranular passing into porphyritic varieties. Potash and plagioclase feldspars occur equally (the K-feldspar in 2 cm crystals) then quartz (30-35%) and biotite (4-8%) with up to 2.6% chlorite. Plagioclase crystals (zoned from andesine cores to sodic oligoclase rims average An25_30) are often decomposed to sericite and zoisite. Accessories are titanite, apatite, pyrite and magnetite. There are rounded xenoliths (under 0.5cm) within the granites in addition to pink and red aplites and pegmatites. The 700 m erosion relief shows the granite neither to be a sill nor a laccolith. Adjacent foliations dip away from the granite and the granite always cuts across the migmatite gneissic structures with which it is always in contact. An age of the 414 • 10 Ma (Early Devonian or late Silurian) was noted by Hjelle (1979) (see Chapter 15). Balashov et al. (1996) from Rb-Sr and single grain zircon determinations confirmed that result with a value of 413 • 5 Ma (Early Devonian on the time scale in this work).

(2) Grey granite dykes. In some migmatite areas aplite and pegmatite sheets cut metasediments. Discordant sheets appear as an initial stage in the genesis of agmatitic migmatites. Other dykes up to 5 m thick which cut micaschists are folded with the country rock. Most dykes, however, cut both metasediments and migmatites with sharp boundaries and some are transitional to the grey foliated granites. Minor intrusions of a variety of types (Hjelle 1979) are extensive in northwest Spitsbergen. The only dates available are from Danskoya (Krasil'shchikov 1964; Krasil'shchikov, Krylov & Alpapyshev 1964) based on K-Ar ages, and recalculated with 1976 constants (but without analytical data) they indicate Early Ordovician to Early Devonian ages, i.e. 483-392Ma. A leucocratic granite from the flank of Fjortende Julibreen gave an Early Silurian K-Ar age of 430 Ma (Ravich 1979).

NORTHWESTERN SPITSBERGEN

Raudfjorden Fault

(WEST)

LIEFDE

Homemanntoppen (granite) Batholith (3)

BAY

Proterozoic KROSSFJO[~,DEN GROUP (2)(7) [Succession north of Liefdefjorden] (6) Lernereyane (marble) Fm, 1.2-1.5 km (7) Pteraspistoppen (marble) Mbr (6)

Generalfjella Fm (1) (marble with pelites)

0 r~ (.9

lower Krossfjorden Group strata

Erikbreen (pelite) Mbr (6) Hornbaekpollen (marble) Mbr (7)

Z Iii a r~

0

Signehamna Fm, 2-2.5 km (1)

(.9 n"

Nissenfjella Fm, >3 km (1)

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BAY

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GROUP

Montblanc Fm (6)

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Kollerbreen Fm, 6-10 km (2)

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CALEDONIANTECTONISM

13_

Migmatites invading

(EAST)

SUPERGROUP

Various granites

SMEERENBURGIAN (Paleozoic) TECTONO-THERMAL EVENT (9)

143

RICHARDDALEN COMPLEX (8) ? Caledonian (early Neoproterozoic-?Grenvillian and possibly Archean elements in high-pressure metamorphic complex)

thrust from the east

Fig. 8.6. Caledonian basement rocks in northwest Spitsbergen; numbers as follows: (1) Gee & Hjelle 1966; (2) Krossfjorden Group named by Abakumov (1976), defined by three formations of Gee & Hjelle (1966) by Harland (1978, 1985); Smeerenburgfjorden Complex named by Abakumov as underlying and older than Krossfjorden Group and including Kollerbreen and Waggonway formations, applied in this work to migmatic and magmatic products of Krossfjorden Group etc., as also suggested by Ravich (1979); (3) Hjelle (1979) mapped Hornemanntoppen Batholith; (5) Gjelsvik (1979) mapped Caledonian basement south of Liefdefjorden; (6) Gee's earlier survey north of Liefdefjorden with units reported in Harland (1985); (7) two of Gee's units renamed here because names were preoccupied, the Lerneroyane Formation replaces Gee's Liefdefjorden Group which was preoccupied in Suess (1888) and the Hornba~kpollen Mbr replaces Gee's Wulffberget marble-conglomerate, which was preoccupied by the Devonian (marble) conglomerate of Murashov & Mokin (1976); (8) Gee's Richarddalen Complex from his earlier survey referred to in Hjelle & Lauritzen (1982); (9) Smeerenburgian used in this work for migmatic and magmatic events in the western northwest sector.

(1) 'Weakly foliated grey granitic rocks' (of Hjelle 1979). Nearly all such granites are associated with migmatites and often with transitional as well as cross-cutting contacts. They may thus 'be considered as "mature" migmatites with a high metatect/metastar ratio' and tend to follow the migmatite rather than the metasediment attitudes. Several bodies occur within or adjacent to the migmatite area and are faintly foliated in places: (a) (b) (c) (d)

east of Krossfjorden-M611enfjorden - a monzo-granite; a dyke-like granite extending northwestwards from Sjettebreen; the granitoid at the middle and inner part of Magdalenefjorden (a granodiorite to quartz diorite); a plagioclase-porphyroblastic monzo-granite east of Smeerenburgfjorden extending southeastwards from Slaadebukta.

From these grey granitic rocks, Balashov et al. (1996) obtained zircon ages of 423 + 22 Ma (two grain analysis) and 461 + 42 Ma (three grain analysis) and 561 + 93 Ma. However, from one zircon grain in a grey granite an age of 952 Ma was interpreted as inherited from a deeper protolith. There is no conflict here with the Caledonian Orogeny and older ages from other inherited minerals in rocks within the granites and migmatites.

8.4.3

Migmatites and gneisses

Migmatites and gneisses, engulfing the older metamorphic rocks, are characteristic of northwestern Spitsbergen and are extensive throughout the older rocks there. In Albert I Land they range from just northeast of Kongsbreen to the north coast, and in the islands (Amsterdamoya and Danskoya). In H a a k o n VII Land they extend from just south of Liefdefjorden continuously in a wide belt to Holtedahlfonna. Schenk (1937) was the first to describe systematically the various gneiss to migmatite facies. Migmatites on this scale are not recorded east of the Breibogen Fault elsewhere in Spitsbergen, the only other area of such development is in Nordaustlandet which is probably Proterozoic. As these rocks occupy a central position in the metamorphic complexes and are flanked by recognizable metasediments, they were first thought to be the oldest rocks (e.g. Archean of Nathorst in contrast to his Hecla Hoek of the related metasediments). Since Holtedahl (1914a) recognized these rocks, and the related metamorphism and intrusions, as representing a post-Hecla Hoek Caledonian event, the first comprehensive accounts of the Northwestern Complex in Albert I Land were by Gee & Hjelle (1966), Hjelle & Ohta (1974) and Hjelle (1979) with detailed petrological studies by Hjelle (1966), Ohta (1969, 1978) and Ravich (1979).

144

CHAPTER 8

In H a a k o n VII L a n d further i n f o r m a t i o n has been provided by Gjelsvik (1979).

Layered gneisses.

In Albert I Land, Hjelle (1979) distinguished the 'layered gneiss' as an intermediate stage in the d e v e l o p m e n t of migmatites from mica schists (pelitic and psammitic). Typical compositions of layered gneisses in percentages are: Mafic layer, quartz 30, K-feldspar 5 plagioclase 35 (An2o-30), biotite 25, garnet+ cordierite + sillimanite 2; Felsic Layer, quartz 35, K-felspar 15, plagioclase 35 (Anl0-2o) biotite 10. Plagioclase porphyroblasts were a late development in the gneisses. However, composition varies considerably according to that of the protolith. The layered material may be mobilised and penetrated by granitic material concordanfly with the gneissosity. Dark micaceous lenses may be entirely enclosed by granitic material. A hornfelsed gneiss from upper C o n w a y b r e e n gave an early to mid-Silurian K - A r age of 430 (Ravich 1979).

Migmatites.

A further stage in the feldspathization and mobilization is seen in migmatite proper as discordant as well as concordant penetration of schists and gneisses by granitic material and with a total loss of original orientation. The inclusions in the migmatites are pelitic, psammitic, calcareous and amphibolitic. Pelitic types are most c o m m o n especially in the absence of marbles. Amphibolites and marbles tend to be associated. Larger xenoliths m a y have a hornfelsed skin and in some xenoliths, folds and b o u d i n a g e d layers are preserved especially in marble. The migmatites are not uniform in distribut i o n - larger bodies of m e t a m o r p h i c rocks do occur, and it is almost possible to discern a ghost stratigraphy. Overall, the bulk composition is that o f a granite or granodiorite. In H a a k o n VII Land, Gjelsvik (1979) reported that the granitic rocks are similar, in nearly all respects, to the grey granite or migmatite of the northwest corner o f Spitsbergen. He noted occurrences of Fe, Mg, Ca silicates near the a b u n d a n t marble bodies. Mineral assemblages indicated upper amphibolite facies. Retrograde metam o r p h i s m is evident in shear zones. Gjelsvik gave details of occurrences at different locations.

8.4.4

Western Northwestern Terrane formations

The Krossfjorden Group. Gee & Hjelle (1966) proposed a lithostratigraphy for the northwest metamorphic complex (west of the RFF) of three formations together comprising the Krossfjorden Group (Harland 1985). Abakumov (1976, 1979) had excluded a pre-Riphean basement to the Caledonian geosyncline which is an integral part of the lowest of the three formations. These divisions were based on the metasediments around Krossfjorden where the effects of metamorphism have been least severe. The less migmatized rocks were mapped approximately as Hecla Hoek rather than Archean by Nathorst (Suess 1888). The three formations are characterized by distinct lithological associations as follows. (3) The Generalfjella Formation, 2.5 km, is structurally the highest of the three divisions. It crops out in two areas: east of Krossfjorden from M611erfjorden to Blomstrandhalvoya, and west of Krossfjorden in Mitrahalvoya. The formation averages 2 km thick in the east but only the lowest 400 m are preserved in the west. Interbedded marble, pelite and psammite is the characteristic association. This formation is best known for the greyweathering Blomstrandhalvoya (marble) Member where the abortive marble mine/quarry was opened up but not exploited. Chlorite-spinel marbles were reported by Burcher-Nurminen (1981) (2) The Signehamna Formation, 2-2.5km, lies below and to the north of the Generalfjella Formation. Pelitic rocks are dominant with lesser psammites and up to 15 m thick units of conspicuous buff-brown quartzites. A few minor marble and amphibolite lenses were noted by Hjelle. Boundaries are transitional. (1) The Nissenfjella Formation, 2-3 km, lies below the Signehamna Formation and crops out on the west coast between Forstebreen and Sjettebreen. Gee & Hjelle (1966) suggested a thickness of 3 km, whereas Hjelle (1979)

calculated 2 km based on the southward plunge of the fold. The facies are pelites, with _<2m thick conformable amphibolites, psammite units and a variety of feldspathic lithologies, which pass northwards into gneisses and migmatites. In the north Ohta (1969) estimated the thickness of these much altered rocks in a deeper tectonic environment as 4-5 km thick.

8.4.5

The Biskayerfonna-Holtedahl Horst formations (Krossfjorden Group)

(a) North of Liefdefjorden Gee (1966) and Gee (in Harland 1985) described the following sequence north of Liefdefjorden partially renamed and re-ranked as follows (Fig. 8.6). (3) The Lerneroyane Formation, 1.2-1.5km (was Gee's Liefdefjorden Group and named for islands in Liefdefjorden) comprises three members the Pteraspistoppen (marble), the Erikbreen (pelite) and the Hornbaekpollen (marble), which was Gee's Wulffberget marble. (2) The Biskayerfonna Subgroup, 4.5-5km, comprises the same two formations as described by Gee. It is reduced to subgroup rank so that whole succession may be accommodated within the Krossfjorden Group. Biskayerhuken Formation, 3.5+ km, is formed mainly of pelites and is similar to the Signehamna Formation to the west. Montblanc Formation, 0.85-1.0km, is made of pelites, quartzites, foliated amphibolites (and gneiss), analogous to the Nissenfjella Formation to the west. These formations suffered upper amphibolite facies Barrovian metamorphism. Their correlation is speculative, and so justifies distinct nomenclature, although there is sufficient similarity to include them in the same (Krossfjorden) Group. Dallmeyer, Peucat & Ohta (1990) from Montblanc Formation by 4~ on amphibole obtained 429 and 437 Ma cooling ages. Muscovite and biotite recorded 402, 413 and 428 Ma (both by 4~ and Rb-Sr) interpreted as cooling through lower closure temperatures. These are interpreted here as mainly Silurian (417-443 Ma), characteristic of the main Caledonian tectogenesis in Spitsbergen ie. equivalent to the Ny Friesland Orogeny. (1) The Richarddalen Complex treated below (Section 8.4.7) is excluded from the Krossfjorden Group (b) South of Liefdefjorden. Gjelsvik (1979) described the types of m e t a m o r p h i c rocks south of Liefdefjorden without proposing a stratigraphic classification. Granitic rocks, migmatite and gneiss form the central part of the ridge and are flanked, and in part overlain, by a sequence of marbles and pelites. The marble does n o t always rest conformably on the gneiss, the b o u n d a r y being often tectonic. The pelites range from phyllite (green schist facies) to mica schist, and pass transitionally into the underlying gneiss. Psammites occur although quartzites are rare and occur in palaeosomes within the migmatites. The marbles are relatively pure calcitic with some interbedded dolomitic marbles. Most of the marbles are banded or bedded in layers from 1 m m to a few d m thick, some are fine-grained and others are coarse. Organic structures were not observed. Gjelsvik's m a p shows marble outcrops t h r o u g h o u t the horst as a regular envelope. Less than 1 k m o f strata are exposed in total to the south of Liefdefjorden and are disposed in an open antiform trending NNW-SSE. Gjelsvik suggested correlation of the marble with the Generalfjella F o r m a t i o n west of the Raudfjorden Fault. This is accepted here, and as the rocks also correlate north of Liefdefjorden the Lerneoyane F o r m a t i o n n a m e is extended southwards.

8.4.6

Conclusion on Krossfjorden Group correlation and deformation

The lithic scheme in Section 8.4.1 above, and applied here, preserves as far a possible the original names for describing the rocks. It does not assume identity o f formations between east and west but allows discussion of correlation.

NORTHWESTERN SPITSBERGEN

145

The marbles described by Gjelsvik are continuous with the Lerneroyane marbles. These are the highest stratigraphic units both east and west and crop out extensively. It has already been noted that the Red Bay (Rivieratoppen) conglomerates in both the east and west are also extensive and have formed largely from local marbles. It is therefore likely that the marble formations were once much thicker more widespread and were actively eroded in Early Devonian time. It is also significant that this general order of lithic types is observed throughout the northwest in spite of intense tectothermal activity. This coherent stratigraphic succession suggests that it was deformed, and suffered major thermal metamorphism only once in Caledonian times. It is therefore argued that it was not affected by significant pre-Caledonian tectogenesis and is thus not protobasement. The exception to the above is the allocthonous Richarddalen Complex which is certainly proto-basement and is discussed below.

8.4.7

The Richarddalen Complex

The Richarddalen Complex comprises a structurally complex group of varied metamorphic rocks contrasting with the Krossfjorden Group (Fig. 8.7). It was first described by Gee (1966), and Gee & Hjelle (1966). Most show polymetamorphic assemblages indicative of high P & T metamorphism with superimposed regression (Dallmeyer, Peucat & Ohta 1990). Eclogite, mylonitic, metabasic and ultrabasic rocks, various gneisses and marble comprise the principal rocks types. All boundaries to the groups are tectonic. It is imbricated with Biskayerfonna Subgroup rocks of the Krossfjorden Group. The Richarddalen rocks are not described in formations and so are strictly a c o m p l e x rather than a group. Several attempts have been made to obtain Precambrian ages. Recent values were obtained from U - P b on zircons in meta-granites and a gabbro (Peucat, Ohta, Gee & Bernard Griffiths 1989) and the 4~ and Rb-Sr results from Dallmeyer (1989). Peucat et al. (1989) suggested that these rocks were derived from reworking at 965 4-1 Ma of ancient crust 'as old as Archaean' (3234 + 43 Ma). In turn they were reworked by later tectogenesis with age determinations ranging from 661 to 402Ma (Ohta 1992) or 382Ma. It is therefore virtually certain that the Richarddalen Complex is not only Proterozoic (Neoproterozoic) basement but probably in part at least Archean. They commented: 'The high degree of discordancy of the zircon data and their typical magmatic habit strongly suggests that the lower-intercept age of 965 4- 1 Ma corresponds to the crystallisation of zircon from the magmas. The small amount of the ancient radiogenic lead indicates a component of Archean crustal reworking. The age of 3234 + 43 Ma can be the mean age of several populations of zircon of different ages; but strongly suggests derivation from Archaean crust' (Peucat et al. 1989, p. 278). Age determinations from eclogite and a 'late' intrusion (felsic neosome of agmatite) identify a later (the latest?) Proterozoic event. K-Ar methods on hornblende gave ages between 520 and 541 Ma (Gayer et al. 1966). Dallmeyer, Peucat & Ohta (1990) by 4~ on amphiboles obtained ages between 500 and 542 Ma, interpreted as cooling following the initial high pressure metamorphism. Rb-Sr ages recorded by muscovite and biotite are younger (410, 418, 420, 423, 430, 465 Ma). The latter are comparable to those of the interdigitated Biskayerfonna Subgroup results noted above, namely Silurian Ny Friesland Orogeny during which the thrusting would have emplaced the Richardalen Complex within the Krossfjorden Group. The earlier (Cambrian) values were not recorded in the Krossfjorden Group and the sequence of tectonism within the Richardalen Complex extended further back in time. Zircons from the ecologite dated by U-Pb method at 620 Ma suggest a magmatic origin and 620 4-2 Ma was suggested for the time of emplacement of the acidic magmas which are younger than the ecologite. The conflicting data nevertheless suggested a tectonothermal event from 660 through 620 to 540Ma (Peucat et al. 1989), i.e. Vendian to pre-Vendian. Whatever interpretation be preferred, a c. 965Ma magmatic event is established (i.e. proto-basement), with relict of an earlier

Fig. 8.7. Generalized geological map of Biskayerhalvoya, northwest Spitsbergen (after Ohta, Dallmeyer & Peucat 1989; Dallmeyer, Peucat & Ohta 1990 all based on survey by D. G. Gee).

proto-basement (somewhere) of Archean age, and a later (latest Proterozoic or Paleozoic) thermal event of unknown significance and finally Silurian tectonic emplacement with metamorphism. The ultrabasites and gabbros at Botnehaugen described by Abakumov (1983) probably belong to this complex.

8.5

Structure

Following the division of the northwestern sector outlined at the outset in this chapter and already applied stratigraphically, the following three terranes bounded by four faults are described, from east to the west (Fig. 8.8). (Ny Friesland terranes Chapter 7) 8.5.1 Billefjorden Fault Zone (BFZ) 8.5.2 Andr6e Land-Dickson Land Terrane (ADLT) 8.5.3 Breibogen Fault Zone (BBF) 8.5.4 Biskayerfonna-Holtedahlfonna Terrane (BHFT) 8.5.5 Raudfjorden Fault Zone (RFF) 8.5.6 Western Northwest Terrane (WNWT) 8.5.7 Kongsfjorden-Hansbreen Fault Zone (KHFZ) (Central west Spitsbergen terranes, Chapter 9)

146

CHAPTER 8

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probable mid-Devonian transcurrence, in Late Devonian (Svalbardian) transpression. After this, further movements have left little evidence of strike-slip, whereas rejuvenation of the zone occurred with mainly Carboniferous basin formation and Paleogene compression. For Devonian history this was the most active tectonic zone for which we have evidence in this sector. The central part of this zone was redescribed from new mapping by M c C a n n & Dallmann (1995), and detail of a small part by Lamar & Douglas (1995). However, the postulated sinistral strike-slip component has not been accepted by all. The matter is addressed at the end of the Devonian Chapter (16). Here only the structural evidence is outlined. Nearly all are agreed on a compressive component as seen in the deformed Devonian strata. The principal Balliolbreen fault, juxtaposing the Hecla Hoek and Devonian rocks, is seen north of Alandvatnet dipping 60 ~ to the east with Hecla Hoek metamorphics on the hanging wall. It has the appearance of a high-angle thrust (McWhae 1953; Harland 1959). Lamar, Reed & Douglass (1986) recorded some sinistral and some dextral reverse oblique slip and some horizontal dextral reverse slickensides on it. Figure 8.9 summarizes their map. The structure is truncated and covered unconformably by Tournaisian and possibly Late Famennian strata of the Billefjorden Group. However, M a n b y (1990) drew a cross section showing it as a normal dip-slip fault. To the west of the main fault are further thrust faults and folds verging westwards. Lamar et al. (1986) mapped these structures in part of Dickson Land (Fig. 8.9). Further north the exposures of the Andr6e Land Group are separated from the metamorphic rocks by Wijdefjorden which widens northwards. However the rocks are folded, occasionally thrust and exhibit cleavage. Carboniferous strata do not extend to the north

Fig. 8.8. Principal structural elements (mainly Devonian) of northwest Spitsbergen.

Sources applied here are Vogt (1928), Schenk (1937), McWhae (1953), Gee (1966), Gee & Hjelle (1966), Gee & Moody-Stuart (1966), Gee (1972), Burov & Semevskiy (1975), Hjelle (1979), Gjelsvik (1979), Ravich (1979), Harland (1985), Lamar, Reed & Douglass (1986), Lamar & Douglass (1995), Gjelsvik & llyes (1991), Thiedig & Manby (1992, 1994), Piepjohn & Thiedig (1992), Manby & Lyberis (1992), Friend et al. (1997); McCann & Dallmann (1995) and personal communications regarding earlier work by P. F. Friend and by A. McCann.

8.5.1

The Billefjorden Fault Zone (BFZ)

Long recognized as a major lineament running N N W SSE, the Billefjorden Fault Zone forms the trench occupied by Wijdefjorden and crosses a narrow isthmus with several sub-parallel faults to Billefjorden, which it crosses obliquely, and thence south under the Central Basin. The first description was by McWhae (1953). The fault separates the high-grade metamorphic Proterozoic Complex of the lower Hecla Hoek sequence in the west of Ny Friesland from the deformed but little altered Old Red Sandstones of Early to Late Devonian age to the west. The main movements were completed at least by Early Carboniferous time or earlier. They were related to the Svalbardian Folding first identified as Late Devonian by Vogt (1928). However, renewed activity along the fault zone allows it to be traced south into the Central Basin where Carboniferous, Permian, Triassic and Jurassic strata show both some syn-sedimentary movements and extensive later Paleogene tectonism. A comprehensive reconnaissance of the fault zone was made (Harland et al. 1974) which postulated a long history of intermittent sinistral transpression and transcurrence culminating, after

Fig. 8.9. Map of central west Dickson Land, simplified from Lamar, Reed & Douglass (1986).

NORTHWESTERN SPITSBERGEN where the pre-Carboniferous age of the deformation cannot be confirmed, but there is a continuity and similarity with the demonstrable pre-Carboniferous structures in the south. The strike-slip structural component in transpression is generally far less evident than its dip-slip (compressive) component. This is the reason why transpression generally went so long unrecognized even though it was logically necessary as a consequence of the interplay of lithosphere motions. Moreover, it is not often recognized that transpression may be partitioned into strike-slip and dip-slip components (e.g. Harland 1971; Teyssier, Kleinspehn & Pershing 1995). The most obvious structural evidence for transpression is in western Ny Friesland, but that is mainly Silurian including the strike-slip mylonitic components which did not develop in Devonian strata to the west. The evidence for continued Devonian strike-slip lies partly in the sedimentological configuration and in stratigraphic contrasts across the Billefjorden Fault Zone. The main structure resulting from the strike-slip component is seen in the 2-3 km Cambridgebreen Shear Zone of low grade chloritic facies immediately to the east of the main fault. This was formed under much lower tectonic load than was the Silurian deformation. It is arguable that strike-slip without transpression was active through late Early and Mid-Devonian time, causing much of the necessary translation of at least 200 km (say 300 km), but that in the final Late Devonian stage the (Svalbardian) folding resulted in a final transition again from strike-slip via transpression and (on locking) to compression. The transpressive structures in the Andr6e Land Group rocks in Dickson Land are consistent with, but not uniquely constrained from, the pattern of fold and thrust orientations which are often not orthogonal. Similarly further north in Andrbe Land, though further removed from the fault zone, are non parallel (en 6chelon) fold axes consistent with sinistral transpression (e.g. from structural data in Piepjohn & Thiedig 1994). Evident compressive structures cannot rule out an oblique component which may be hidden in strike-slip. The evidence of strike-slip is in the Cambridgebreen Shear Zone. The seismic E - W profile just south of this study area shows Hecla Hoek basement with less than 2 km of cover (Late Paleozoic) to the east of the BFZ against which a wedge 10-11 km thick of mostly Devonian strata abuts the vertical fault and thins westward (Faleide et al. 1991). It would be difficult to explain this crosssection other than by Late Devonian strike-slip.

8.5.2

Following Vogrs (1928) identification of the Svalbardian Folding in the east of the terrane, Schenk (1937) described the whole structure in outline. The next structural study was by Friend in the early fifties in the course of his stratigraphic and sedimentological investigations. These were not published and his block diagram appears here as Fig. 16.8 depicting the structure of the eastern belt. Burov & Semevskiy (1979) gave the first systematic description of the structure of the whole Devonian outcrop; but only in outline. More detailed observations were made by Piepjohn (Piepjohn & Thiedig 1992) on the structures as seen from Woodfjorden. The following account draws on these sources and is interpreted from the author's own visits to most areas over many years. The rocks deformed in this terrane belong almost entirely to the Andr6e Land Group (Early Devonian to early Late Devonian) and the age of folding is at least pre-Carboniferous and therefore late Devonian. The intensity of deformation diminishes westwards so that the most intense folding is seen just west of the Billefjorden Fault Zone. The strata east of the Breibogen Fault (as seen in Reinsdyrflya and west of Bockfjorden) are generally flatlying with minor disturbance. The main deformation is thus seen in Andr6e Land and Dickson Land which probably owe their mountainous nature to the folding which is intense in places. Schenk (1937) showed the above distinction in his cross section of Northwest Spitsbergen with the strata east of the Breibogen Fault dipping gently eastwards and the main body of Andr6e Land strongly folded with upright folds. Burov & Semevskiy divided the area by a main anticlinal axis running due south from Gr~huken, the northern tip of Andr6e Land, nearly to Dickson Land. They distinguished Dickson Land as largely occupied by their Wijdefjorden Fault Zone, which also extends on the northeast coast of Andr6e Land. The northwest coast of Andr6e Land was bounded by their Woodfjorden Fault Zone running N E parallel to the shore. A synclinal axis to the west parallels the anticlinal axis. As with many Russian tectonic interpretations their map is dominated by block faulting. Piepjohn & Thiedig (1992) described some folds in more detail. A cross section (Fig. 8.11) from the main Andr6e Land Anticline westwards shows the style of upright folding in the north deforming Grey Hoek strata. On the eastern flank of the anticline the minor fold axes (with one exception) plunge S to SSW, i.e. oblique to the N N W trend of the BFZ. This supports the impression of early Cambridge parties that (en 6chelon) oblique folding, consistent with sinistral strike-slip in northern Andr6e Land. Only one plotted exception is parallel to the fault zone. To the west of Andr~e Land the folds are somewhat asymmetric and verge westwards which is consistent with the manifest westward thrusting seen further south in Dickson Land. Burov & Semevskiy described three linear belts of intense folding and faulting. Their parallelism with the principal bounding faults and lack of deformation in the intervening areas suggested rejuvenation of activity along buried faults. (i) Along the eastern boundary of the terrane is a zone of deformed Devonian rocks up to 4 k m wide to the west of the Balliolbreen Fault of the (BFZ). This zone and Hecla Hoek

The Andr6e Land-Dickson Land Terrane

This terrane, clearly defined between the BBF and the BFZ, is the exposed repository of Devonian sediments and has generally been referred to as a graben. However, the Billefjorden Fault Zone (BFZ) which defines its eastern margin appears to truncate a once more extensive basin and has a significant post-Liefde Bay Supergroup history. Moreover, there is no clear western boundary fault system to the west.

ALBERT

I LAND

147

HIGH

BISKAYERFONNA

~-r~

HOLTEDAHL, FONNA J BLOCK

I I I

,~,~ 'i

ANDRI~E

LAND

BASIN

Raudfjorden Fault Breibogen Faulll Woodfjorden Andr6e Land Syncline Anticline Hannabreen Fault I SiktefjelletGroup I t ~. RedBay ~, ; / GreyHoekFm Woodfjorden X '~r,... . . . ~, , / ' l . "~'~'~s-'" ~*J. ' ~ " , . L ' ~~. X Group ~

"~

"J Basement

\

+ + + , + ", ,s'.-\ " % / / + + + +l+ + / Basement

4-

Fig. 8.10. Generalized cross-section across northwest Spitsbergen, from the Albert I Land High to the Andr6e Land Basin (modified from Hjelle & Lauritzen 1982).

OL

0

I

5

I

10

115

21

\!

~.~..:J.. ~ bfWoodBayFm ~ i ?unknown

depth to basement?

/Wijde Bay Fm / ijdefjor den

148

CHAPTER 8 Folding, of course, occurred before peneplanation a n d extrusion of Cenozoic lavas. / !/

//

WEST

!

1 km

Transition to the Andree Land Anticline HAST

|

ilryj3 Fig. 8.11. Structural profile across the Andr6e Land anticline between GrAhuken and Mushamna, simplified from Piepjohn & Thiedig (1992, fig. 5). deformation east of the fault constitute the Billefjorden Fault Zone. In northern Dickson Land it is 1.5-4kin wide and termed the Gr5kammen Graben (Burov & Semeviskiy 1979) (Fig. 8.8). Burov, Semevskiy et al. (1996), in describing the structure of south eastern Andr6e Land and especially the faults, referred to 'the eastern boundary zone of faults' (of Livshits 1974) with a total displacement along this zone of 3 - 4 k m . Within the zone the authors recognized a subzone of 'main strike-slip faults' on the east, and a subzone of 'shears and linear folds'. The boundary between the subzones is marked by a narrow (2-2.5km) Gr~kammen Graben. Its eastern margin encompasses a vertical zone of breccia (30-70m wide) cemented with quartz and calcite. The authors related the monchiquite dykes to the faults within the subzone. (ii) The Gronhorgdalen Belt can be traced for about 60 km with a maximum width of about 5 km (Fig. 8.8). The Wood Bay Formation is seen in a series of steeper dipping western limbs of the anticlines which are truncated and overstepped by Carboniferous rocks in the south. The fold axes are parallel to the belt or cut across it in a NNE-SSW direction. Plunges are commonly steep (60 ~ and to the south. Burov & Semevskiy (1979) described the Vestfjorden synclinal immediately to the east of the Gronhorgdalen Belt. (iii) The Orsabreen Belt appears to be a system of symmetric anticlines. Relatively discontinuous deformation can be traced south for 20 km with a width of 1 km. Similar trends and relationships to the Gronhorgdalen Belt are found, although on a smaller scale; but it is cut by a major longitudinal fault with a downthrow of 400-500 m to the west. This fault also affects Carboniferous and Permian rocks to the south with a throw of least 400 m. Further north, strong folding affects the Andr6e Land Group resulting in the broad Andr~e Land Anticline and Woodfjorden Syncline (Figs. 8.8 & 8.10). The Andr6e Land Anticline may be a continuation of the Grenhorgdalen Belt although much broader or, according to Burov & Semevskiy (1979), it could curve into the BFZ near Vestfjorden. The anticline culminates around Kartdalen and its steeper eastern limb (20-25 ~ is referred to as the East Andr6e Land Monocline (Burov & Semevskiy 1979). Small NNE-SSW and E - W trending folds are found in this area. The Woodfjorden syncline (Burov & Semevskiy's Andr6e Land syncline) exposes a number of large and small scale chevron type folds with steep dips and steeper dipping western limbs. They reported that the main syncline dies out to the south, while in the north the axis of the synclinorium is coincident with their Prinstoppen Graben Anticline. The small scale folds plunge north and south, possibly resulting from E - W cross-folding. The folds as a whole indicate that the maximum principal stress was WNW-ESE, consistent with sinistral transpression. Mention should be made of the hypothesis of Chorowics (1992) who proposed that, because some soft sediment deformation identified implies an eastward motion, the basin floor sloped to the east and the sliding sediments left areas of extension in the west with compression, against the Ny Friesland block in the east. It is not clear to what extend he proposed this as a supplementary or as an adequate process to account for the Svalbardian folding.

8.5.3

The Breibogen Fault (BBF)

The BBF parallels the Raudfjorden Fault and similarly is not seen to cut Wood Bay strata south of Holtedahlfonna. Therefore, the principal movements had probably ceased before deposition of the Andr~e Land Group. That is the time of the Monacobreen Diastrophism. The fault is straight and vertical and its trace is distinct across country visible by the contrast of red Wood Bay strata on the east and dark metamorphics on the west. In the cliff at Breibogen the red beds are poorly exposed, but on the other side narrow shear zones with mylonites extend at least 500m to the west and are more concentrated near the fault. A coarse sedimentary Wood Bay Formation breccia occupies much of the shore on the east side, again indicating some contemporaneous activity of the fault. Further east these strata exhibit a gently eastward-dipping regional homocline (5 ~ although dips steepen near the eastward dipping normal fault. Sporadic conglomerates in the Wood Bay strata thicken towards the fault and suggest some activity during deposition. On Fotkollen, immediately to the west of the fault (and NE of Siktefjellet) is a 150 m wide zone of shattered sandstone much coarser than the Wood Bay Formation and suggestive of Red Bay sandstone facies. West of this zone is another zone of shattered pelitic and psammitic schists. Fragments show a marked lineation; but in situ orientation was not seen. Still further west typical psammitic (to pelitic) schists occur. About 2 km to the south, on Siktefjellet, the Wood Bay Formation strata appear to be faulted directly against dense (indurated) Siktefjellet Group quartzites. Some loose blocks show mylonitic texture which is itself brecciated but, as above, in situ structures were not easily accessible. Near the north shore of Liefdefjorden, feature and float mapping suggested that at least two faults juxtapose metamorphic rocks and Siktefjellet Group rocks. With an inferred 2 km offset to the east, the BBF resumes its course from Liefdefjorden to Bockfjorden, separating Wood Bay Formation to the east from the Andr+ebreen Formation to the west. South of Bockfjorden the zone of Quaternary volcanic activity coincides with the BBF. The fault then extends southwards to Holtedahlfonna south of which the Wood Bay Formation, overlain by Late Mississippian strata, appears to cross the line without deflection (Hjelle & Lauritzen 1982, map 3G). Still further south a conceivable continuation in line appears as a fault throwing Triassic rocks down against Carboniferous and Permian - a fault which curves round west of Bohemannflya and Erdmannflya. However, excepting this last deflection in much younger rocks, which may not be related, the fault trace along the Liefdefjorden Belt is so straight as to require a strike-slip origin.

8.5.4

Biskayerfonna-Holtedahlfonna Terrane (BHFT)

This terrane, bounded by two straight and parallel faults (BBF & RFF), is a N N W - S S E strip exposed for 100 km N-S and 10-17 km wide. There are two distinct elements subparallel to the boundaries. (i) a N-S horst of metamorphic rocks of the Krossfjorden Group, capped by marbles and with a core of migmatite, pelitic schist and marbles. This is the Biskayerfonna-Holtedahlfonna Horst; or in this context 'the horst'. (ii) To each side, mainly on the west, are elongated troughs or basins of Red Bay Group (recently mapped by A. McCann, pers. comm.) and some Siktefjellet Group strata. To anticipate, this terrane is interpreted as having suffered intense main Silurian Caledonian tectogenesis with thermal mobilization in which the fault systems developed possibly out of a sinistral transpressive orogeny and between which the latest Silurian early Devonian sedimentation was controlled by continued alternating transtension and transpression. Fault scarps are interpreted

NORTHWESTERN SPITSBERGEN

149

as having provided much of the sediment, the transpression inducing the deformation. These extended Haakonian phase movements ceased during late Red Bay Group time (Friend et al. 1997). The two elements are separated by the oblique Hannabreen Fault which runs NW-SE from midway in the terrane to the north to join the Breibogen Fault south of Liefdefjorden at Bockfjorden.

Because the Hannabreen fault in the north appears with downthrow to the west and in the south with downthrow to the east, it has been suggested as a scissors fault. However it seems more likely to be a strike-slip fault not evident where the scissors' hinge would be, because it was not active after deposition of the overlying upper Red Bay Group strata.

(a) North of Liefdefjorden. To the west is the Raudfjorden Basin, which has long been seen as a synclinal structure occupied (except in the south) entirely by conglomerates, breccias and sandstones of the Red Bay Group. Most of the area is obscured by Raudfjorden itself (Red Bay), by western Liefdefjorden and the glaciers between them. In the south (north of Liefdefjorden) the Red Bay conglomerates rest unconformably on basement composed of marbles and pelites (Lerneroyane Formation). To the east, and occupying the high ground from Biskayerhuken in the north to Siktefjellet in the south, is a complex - the Biskayerfonna H o r s t - in which three distinct components have been identified. (i) The essential core of the horst is formed of metamorphic rocks of the Krossfjorden Group and dominated by schistose pelites in the north (Biskayerhuken Formation) and are underlain by pelites, quartzites, amphibolites and gneiss (Montblanc Formation). (ii) The Richarddalen Complex is a thrust mass of older rocks resting on and in the Biskayerfonna subgroup. It is noteworthy for its eclogites and other high grade rocks of distinctive appearance and its established Proterozoic tectonothermal history in contrast to (i) above which together with (ii) suffered Caledonian tectogenesis. This distinctive complex is not matched elsewhere in the Biskayerfonna-Holtedahlfonna terrane nor in that to the west. It is possible that, being an allochthonous thrust mass, it was transported westward from the Andr6e Land terrane basement in the east where the basement is nowhere exposed. (iii) The Siktefjellet Group of Silurian or Devonian clastics is the oldest of the Liefde Bay Supergroup and exposure is confined to the southern part of the Horst, north of Liefdefjorden. Northerly tectonised basal conglomerates and sandstones are succeeded in the south by conglomerates and sandstones of the lower formations of the Red Bay Group. The stratigraphy, structure and petrogenesis of this horst structure north of the Liefdefjorden were largely worked out by D. G. Gee (Gee 1966; Gee & Hjelle 1966; Gee & Moody-Stuart 1966) with subsequent work by Cambridge, Mtinster and Oslo Groups. Ohta, Gjelsvik & McCann (1995) noted a Horneb~ekpollen thrust zone in Liefdefjorden.

(c) South of Liefdefjorden. Whereas the Rabotdalen Fault appears as a vertical feature with indications of strike-slip the Bockfjorden Fault is a high angle thrust, which dips east with possible low angle thrust masses and klippen of the Andr6ebreen sandstone overlying the metamorphic horst. First mapped as klippen (Gee & MoodyStuart 1966) the possibility of unconformable outliers cannot be ruled out). The fault zone seen near the south of Borebreen has some irregular mylonitic patches consistent with earlier strike-slip later disturbed by dip-slip. The larger southern or Holtedahlfonna segment of the Biskayerfonn~Holtedahlfonna Horst was mapped in some detail by Gjelsvik (1979) and subsequently the Germaniahalvoya area bordering in Liefdefjorden has been worked by a German group (e.g. Piepjohn & Thiedig 1992).

(b) The Hannabreen Fault lineament (Rabotdalen-Bockfjorden Fault). This enigmatic structure runs obliquely between the two boundary faults (BBF and RFF) from north of Rivieratoppen through Hannabreen, across Liefdefjorden to join the Breibogen Fault south of Bockfjorden. It is relatively straight and a controlling feature to the north and the south but not obviously continuous at the surface in the middle tract north of Hannabreen. North of Liefdefjorden it bounds between the Biskayerfonna Horst and the Raudfjorden Basin and between the Biskayerfonna Group metasediments to the east and the Lerneroyane marbles and pelites to the south (HBF on Fig. 8.4). South of Liefdefjorden the main horst of Lerneroyane marbles rests on the lower formations of the Krossfjorden Group, and occupies the high ground to the west of the Hannabreen Fault. To the east are Red Bay Group sandstones of the Andr6ebreen Formation and the enigmatic ?late Ben Nevis Formation rocks distinguished by A. McCann (pers. comm.). The fault is a distinctive feature, probably with an earlier Caledonian strike-slip history rejuvenated differentially with dip-slip displacement in late Red Bay time. It has also been referred to where best seen as the Rabotddalen Fault in the north (Gee & Moody-Stuart 1966) and to the south a less regular trace, but still a major tectonic feature is referred to as the Bockfjorden Fault. Hannabreen unites the two but the fault cannot be seen there.

East of the Hannabreen Lineament (Bockfjorden Fault) is the strip of Andr6ebreen Formation as correlated by Gjelsvik & Ilyes (1991). It had been thought to be part of the Siktefjellet Group rather than Red Bay Group partly because of its intense deformation (Gee & Moody-Stuart 1966). Samples of structural detail in small E - W transects were depicted by Piepjohn & Thiedig (1992, fig. 4). The strata, generally striking N-S, dip steeply both E and W with complex variations including folds and breccia zones. High angle strike faults are mostly normal, others and lower angle faults are reverse. Oblique faults generally trend N E - S W and mostly, but not all, show sinistral strike-slip displacements. The picture is of remarkably complex and intense deformation with a dominant net compressive E-W component and later relaxation, although this cannot be explained without a degree of transpression. Immediately east of the Breibogen Fault the Wood Bay strata are virtually undeformed so making this a Haakonian deformation phase of Gee (1972) not pre-Red Bay (as Gee & Moody-Stuart suggested) but continuing to mid-Red Bay Group time. Coeval diastrophism is evident north of Liefdefjorden but by no means with this degree of tectonism. West of the Breibogen Fault and south of the Hannabreen Fault. The Holtedahlfonna Horst is the core of the terrane south of Liefdefjorden. Piepjohn & Thiedig (1992) recorded the metamorphic Krossfjorden Group succession thus:

marble (Lerneroyane Fro) pelite (Biskayerfonna Subgroup) (gneiss) migmatite Mapped by Gjelsvik (1979), the migmatite and pelite forms the axis of the horst and the marble the outer cover which is disposed anticlinally so as generally to crop out along the flanks. The Sverrefjellet Quaternary volcanic cone formed where the Breibogen Fault joins the Bockfjorden (Hannabreen) fault. The structure seen in the pelites in Germaniahalvoya, and depicted by Piepjohn & Thiedig, shows a complex pattern of bedding foliation with flatlying isoclinal folds and asymmetric overturned folds with low dips to the west and verging eastwards (Fig. 15.4). This is interpreted as the main Caledonian structure which preceded the sedimentation of the Liefde Bay Supergroup rocks. The lineation is N-S and boudinage noticed by the author in the marbles also suggests N-S elongation, in a dominantly compressive regime, possibly verging into a transpressive one and leading to the transcurrent movements as seen in the two bounding faults. These same deformation structures are found in the xenoliths and palaeosomes of the migmatites.

150

CHAPTER 8

The horst plunges northwards about 5~ to 10~ at Liefdefjorden so that the migmatites do not appear north of Liefdefjorden. Preston (1959), who described in some detail the southern end of the horst, noted a NNW-SSE fault between Snofjella and Dovrefjell with downthrow to the east and Red Bay strata flanking each side. Minor marginal normal faults are sympathetic with the antiform. However, along the western part of the ridge there is a system of reverse faults involving both crystalline and Red Bay rocks. The only deformation suspected to be of Paleogene age is seen in the sinistral offsets of all three fault lineaments (Breibogen, Hannabreen and Raudfjorden). One set of offsets of about 2 km each is at the latitude of Liefdefjorden, another further south from Seligerbreen, to B6rrebreen, more at Svertefjellet, and still further south at Sigurdfjellet opposite the head of Wijdefjorden. Seen on the 1:500 000 map of Hjelle & Lauritzen (1982) these displacements could all be the response north of the West Spitsbergen Orogen of its thrust to the NE. A structural study of Red Bay Group strata south of Liefdefjorden by A. McCann (pers. comm.) suggests inter alia that the strike-slip fault running SE from Hornemantoppen swings round into an east-verging thrust along the eastern outcrop of the Red Bay strata east of Monacobreen. This could also be a Paleogene effect, but he did not think so. Indeed he argued that the long straight antiformal horst, which appears truncated south of Holtedahlfonna by relatively undeformed Wood Bay Formation, was deformed in a distinctive Monacobreen Phase, marked by the inferred unconformity between the Red Bay and Andr~e Land groups. It might be added that the straightness of the antiform, parallel to the boundary faults (RFF & BBF) could be a transpressing rejuvenation of those faults.

8.5.5

The Raudfjorden Fault (RFF)

A NNW-SSE-trending fault along Raudfjorden, Monacobreen and Isachsenfonna has appeared on most geological maps since Nathorst's (Suess 1888) map. It follows the tectonic grain of the northwest complex and does not appear to cut either Wood Bay or Carboniferous strata south of Kronebreen. Some maps (e.g. Dallmeyer et al. 1990) connect it with the Pretender Fault which cuts Carboniferous and Devonian rocks (Andresen & Welbon 1991) although the latter is 5-10 km west of the projected southward trace of the straight Raudfjorden Fault. At Konglomeratodden (east of Raudfjorden) metamorphic rocks to the west are faulted against the Konglomeratodden Member to the east, which underlies the Wulffburget Member of the Rivieratoppen (conglomerate) Formation. A straight line can be drawn south separating exposures of metamorphic from Red Bay Group rocks. However, there are few localities where the actual fault contact can be observed as A. McCann (pers. comm.) has reported. With the exception of the minor sinistral offsets which are paralleled in the Breibogen Fault and are of presumed Paleogene age the straight trace implies an origin by strike-slip possibly following transpression. Once formed, such a fundamental fault would be the locus of later displacement.

8.5.6

Western Northwest Terrane

The northwest part of Svalbard, west of the Raudfjorden Fault (RFF) is a unified terrane, comprising mainly pre-Devonian metasediments and related igneous rocks with local occurrences of overlying or in-faulted Devonian deposits. The general trend of both structural fabric and lithological boundaries is N S . The overall structure may be described as an anticlinorium to the west and synclinorium to the east plunging gently to the S and so exposing deeper structural levels successively towards the centre and north.

Hjelle (1979) subdivided this complex into four areas: (i) (ii)

(iii)

(iv)

southern area predominantly of metasediments (the Krossfjorden Group); central and northern gneisses and migmatite area in which high grade metamorphics are intruded by a late tectonic batholith; western transition area (predominantly metasediments at higher grade than area (i) and bounding area (ii) in the west with transitional facies; eastern transition area, similar to (iii) but on the eastern flank.

Polyphase deformation was recognized in the metamorphic rocks to the south by Gee & Hjelle (1966) and Hjelle (1979). Of the three fold facies distinguished, the majority were identified as F2 which is associated with minor thrusting verging to the west. The thrusting was suggested to be related to the main mid-Silurian tectogenesis occurring here in lower to upper amphibolite facies; it could be later. The peak metamorphic conditions (inferred from garnet textures) appear to predate F2 in the south: the F1 event was associated with upper amphibolite facies in the late Proterozoic and early Paleozoic interval. However, evidence of an F2 fabric in the palaeosome of the migmatites indicates that migmatization postdated F2. F3 on the above scheme would be the formation of the anticlinorium and may be associated with faults downthrowing to the west in the west. Emplacement of the Hornemantoppen Batholith occurred during the last phases of ductile deformation. The intrusion was dated at 414-t-10Ma (Rb-Sr) and movement on the major westward directed thrust between Lilleh66kbreen and Smeerenburgfjorden may be related to emplacement of this granite. In the deeper rocks of the Nissenfjella Formation to the north, Ohta (1969) described the gneisses in three stages from fine grained banded gneisss, through layered gneiss to granitic migmatite. Successive fold phases showed a general foliation dip to the east with a gentle southerly component and a consistent N-S lineation. Then the granites were formed: firstly a plagioclase-porphyroblastic granite, then a grey granite and then the Hornemantoppen quartz monzonite. The last two were described as late and posttectonic. Their NW-SE trend cuts obliquely across the earlier N-S fabric. It is consistent with a local sinistral transtensional phase. There seems to be too little evidence from which to distinguish more than one mid-Paleozoic tectonic sequence. Two narrow Devonian graben trending NNW-SSE are superimposed on this in the south at Mitrahalvoya and Blomstrandhalvoya. In both areas extensive red staining at the surface suggests an exhumed Devonian unconformity, but the sediments are only preserved in the graben. Of these the Blomstrandhalvaya-Lov~noyane Basin is the best known in which the pale marbles of the Generalfjella Formation contrast with the overlying red sediments exposed both on the peninsula (now an island) and on the islands scattered in Kongsfjorden. Gjelsvik (1974) first drew attention to these rocks on the islands (which for many years have been bird sanctuaries until 15 August) (Fig. 8.8). The sediments are locally derived red conglomerates and grey green sandstones, shales and pebble conglomerates and resemble the rocks of Raudfjorden in both lithology and setting and are probably equivalent to the Red Bay Group. Russian geologists were said to have found fossils suggesting Early Devonian age. The structural setting is complex. Gjelsvik (1974) suggested a narrow graben bounded by steep faults which are observed as shear zones in two localities. The sheet, 3G of Hjelle & Lauritzen (1982) showed a western fault as a thrust from the west with marble on the hanging wall over Devonian. However, their eastern margins show marble to overthrust the sediments towards the north or northwest. Thiedig & Manby (1992) from the mapping of research students (M. Kempe and U. Nieloff) described the structure of Blomstandhalvoya which, in E-W section through N-S striking faults and folds, shows westwards verging folds and thrusts. This is consistent with either Haakonian or Svalbardian deformation and not

NORTHWESTERN SPITSBERGEN with Paleogene deformation which would be expected to strike N W - S E and verge to the NE. Sediments were all generated by active faulting which would suggest Haakonian transpression as in the Biskayerfonna-Holtedahlfonna terrane.

Mitrahalvoya. An analogous but smaller N S structure (15-18 km W of the above) is evident in Mitrahalvoya, the faults and red staining obtain but no sediments have been recorded.

The Kollerbreen zone. A Kollerbreen Formation has been introduced in the notes to Fig. 8.6. Ravich (1979) not only regarded it as a Caledonian migmatite complex but he drew attention to a narrow zone 2-4 km wide, extending 40 km N-S from Kollerbreen (at the head of the NE branch of Krossfjorden to Kronebreen at the head of Kongsfjorden. Its contacts with other units were described as mainly tectonic. It is indeed a fracture zone and this may have led Abakumov to treat this sheared migmatite as early Proterozoic. Ravich described its petrology in detail. This fracture zone would appear to be another ?Early Devonian strike-slip shear zone. Abakumov & Chaika (1996) described this 'Smeerenburgfjorden Group' as including the highest grade rocks in the area with amphibolite facies metamorphism and relicts of granulite facies.

151

(3) Late Neoproterozoie. The Richarddalen Complex also shows evidence for a thermal event around 620 Ma.

(4) Mid-Silurian: main Caledonian-Smeerenburgian.

The time of deformation and Smeerenburgian magmatism of the Krossfjorden Group strata (and adjacent Richarddalen Complex) is constrained by metamorphic ages, by the age of the late and post-tectonic granites, and by the unconformable cover of both Siktefjellet and Red Bay Group conglomerates which, while deformed, have neither suffered such intense tectogenesis nor recorded any tectonothermal activity.

(5) Late Silurian-Early Devonian: Haakonian. The main structures affecting the Siktefjellet through Lower Red Bay Group formations are constrained within the Biskayerfonna-Holtedahlfonna terrane probably before or during Fr~enkelryggen Formation time. It is thought likely that the sedimentation and structures seen north of Kongsfjorden were also formed in a coeval episode. A late Devonian age is also possible. However, relatively undeformed Wood Bay strata occur to the southeast which makes it less likely that these structures resulted from Svalbardian movements. (6) Early Devonian (post-Red Bay, pre-Andr& Land groups).

8.5.7

The Pretender Lineament

Possibly appropriately named, this lineament has been postulated as extending south from the Pretender Fault east of Ny-Alesund through outer Isfjorden and south beneath the fold belt of the West Spitsbergen Orogen or beneath the Paleogene formations of the Central Basin. It was suggested (Welbon & Andresen 1992) that it may have had a Devonian history by analogy with parallel faults to the east described in the foregoing sections, moreover, that it marked the boundary between the Nordfjorden Block and the St Jonsfjorden Trough. It had been suggested (Mork et al. 1982) that the lineament was active in Triassic time and was the locus of thickening of Triassic strata westwards. However, in Chapters 10 and 18 it is argued that the observed thickening does not require a fault. For these pre-Cenozoic functions other faults might serve as well or even better, such as the Kongsfjorden-Hansbreen Fault postulated as a terrane boundary (Harland & Wright 1979; Harland, Hambrey & Waddams 1993). The visible evidence as described by Welbon & Andresen is of a fault, or fault zone, in the Pretender Mountains with E - W extension, and normal faulting down to the west, and approximately 400 m offset (?apparent dextral). Paleogene deformation structures are cut by these faults which are thus post-Eocene or later. The older displaced rocks appear to show no evidence of syn- or presedimentary faulting so that the earlier history is surmise. However, the opinions expressed in their abstract (Welbon & Andresen 1992) may well be justified when more evidence is published.

8.5.8

Timing of deformations

A summary of conclusions with a discussion of the Paleogene component of deformation follows. (1) Arehean. Zircons in the Richarddalen complex indicate a possible event around 3234 4-43 Ma but it is not related to any recorded structure.

(2) Early Neoproterozoie: 'Grenvillian'. The Richarddalen Complex records clear isotopic evidence of a tectonothermal event around 965 Ma.

Folding of Biskayerfonna-Holtedahlfonna anticline. This was referred to by McCann (pers. comm.) as the Monacobreen Phase. (7) Late Devonian: Svalbardian. The main structures affecting the Andr& Land Group strata are clearly Late Devonian in the south where constrained by an unconformable cover of ?late F a m e n n i a n Tournaisian strata. There is no obvious constraint in the north where there is no Carboniferous outcrop. There was certainly a compressive component. Evidence is also consistent with transpression which has not been disproved. The tectonic sequence could be: transcurrence-~ transpression-+ compression.

(8) Carboniferous: 'Petunian' from Petuniabukta.

To the south of the sector movements in line with the above mentioned faults continued at least through Moscovian time, and appear to have been extensional as in the Billefjorden Trough. An extensional regime would have been consistent with the intrusion of the monchiquite dykes at Krosspynten dated at 3 1 5 + 5 M a (Gayer et al. 1966 recalculated c. Bashkirian) also along the Billefjorden Fault Zone. (9) Paleogene: Spitsbergian. The West Spitsbergen orogeny is known to have deformed strata, conspicuously late Paleogene, but also Mesozoic, as far east as the Lomfjorden Fault Zone. Thrust structures along rejuvenated older fault zones are well established. It would therefore be surprising if such effects did not extend at least a little north of the main Carboniferous outcrops so that the minor deformation of the Krosspynten dykes is consistent with this effect (Manby & Lyberis 1992). On the other hand the main orogeny in the west is conspicuous only a little north of Kongsfjorden (Welbon & Andresen 1992). For example the Lomfjorden Fault Zone which cuts Carboniferous strata well north of the deformation reported by Andresen et al. (1992) appears not to be affected. Therefore there is no reason to attribute any of the main deformation of Devonian or earlier strata to the effects of the West Spitsbergen Orogeny. Moreover, the vergence of the Andr& Land and Dickson Land Devonian structures is westward which is the opposite of all the Paleogene effects. Cleavage in the folded structure in north Andr& Land is argued by Manby & Lyberis (1992) to have required more overburden than would have been supplied by Devonian strata. It is not known what Devonian strata were removed, and in any case the fold structure, claimed by those authors to imply a stratal shortening of

152

CHAPTER 8

not less than 45% might well have built up the necessary overburden. In any case the basal Paleocene unconformity cuts down through cover strata back to Permian at Kongsfjorden and further north erosion had probably removed most post-Devonian cover by Eocene time. Similarly the westward verging structures north of Kongsfjorden do not fit a Paleogene eastward verging model. The most likely Paleogene deformation in the Northwest sector is the sinistral displacement of the two otherwise straight faults (Raudfjorden and Breibogen) and also the related oblique faults, notably one trending ESE, sinistrally displacing the northern part of the Hornemanntoppen Batholith, passing through the head of Liefdefjorden where it displaces the RFZ and possibly bounding the Red Bay Group on the east of Monacobreen as the thrust structure noted by McCann (pers. comm.). While not constrained in age it is eastward verging and so is sympathetic to the kinematics of the West Spitsbergen Orogen. A distinctive deformation belt extends up to 4kin on either side of the Billefjorden fault forming a wide zone with presumed Paleogene displacements as outlined by Harland et al. (1974) and upgraded by McCann & Dallmann (1996).

8.6

Offshore geology

The offshore area to the north of Spitsbergen consists of a shallow, flat region with water depths less than 200m. To the west and northeast, this bank drops off sharply onto the abyssal plain of the Eurasian Basin, with water depths in excess of 1500m. To the northwest the bank drops only slightly to a plateau, with depths about 800 m. The plateau extends to the north and curves round in a hook-shape to the northeast, where it slopes off onto the abyssal plain. This hook-shaped seafloor promontory is the Yermak Plateau (Fig. 8.12). The shallow inshore areas contain several smaller banks and basins. In particular, these are Sjubrebanken, to the west of Albert I Land; Danskoya Basin, to the northwest of Albert I Land; and Norskebanken, to the north of Haakon VII Land and Andr6e Land.

8.6.1

The geology of the plateau has been subject to geophysical surveys (e.g. Feden, Vogt & Fleming 1979; Jackson et al. 1984; Eiken 1993) and by the Ocean Drilling Program (Myrhe, Thiede & Firth 1994). It has generally been proposed that the northern part of the plateau comprises some form of oceanic crust, wheras the southern portion is of continental character similar to Svalbard (Feden, Vogt & Fleming 1979). It has been interpreted by Feden et al. and Jackson et al. as once having lain adjacent to the Morris Jessup Rise, situated off northern Greenland. Together, they may have formed an Iceland-like massif of oceanic crust, with the greatest rate of plateau development occurring between anomaly 18 and anomaly 13 time. The massif split after anomaly 13 time when the North American and Eurasian plates drifted apart. Jackson et al. recorded four seismic profiles. Off the northern flank of the plateau (line 1) lies oceanic crust of the Eurasian basin, with up to 2 km of sediment cover. The oceanic crust within the basin is thin, only 2-3 km. On the plateau itself, line 3 reveals 8 km of crust similar to layer 2 oceanic crust, underlain by a minimum of 10km of crust similar to layer 3 oceanic crust. On line 4 the southern end reveals continental crust similar to that throughout Spitsbergen. Gravity data indicates that the crust off the plateau is only approximately 20 km thick, which for the continental crust represents significant thinning, perhaps by as much as 20%. Seismic data for the southern part of the plateau was provided by Eiken (1993). Over 1 km of well-stratified sediments are present in the area, except for in the vicinity of the Sverdrup Bank which has no basement cover. Three sequences were recognized in the cover strata: YP-1, YP-2 and YP-3. Sequence YP-1 is only observed in the SW-most part of the plateau. It consists of subparallel reflectors, and infills basement topography. Assuming that topography was rift-related, then the sequence is probably of Neogene age. Sequences YP-2 and YP-3 show evidence of working by bottom currents, probably from the West Spitsbergen Current as it flows northwards into the Arctic Ocean. The seismic sections show smooth reflectors from the top of fault blocks, many of which are tilted. Eiken (1993) believed that Tertiary strata were probably present beneath the Sverdrup Bank. Basement rocks were not observed beneath the thick sedimentary cover at Sophie Canyon. West of the Hornsund lineament YP-2 downlaps to the west, and forms an elongate NNW-SSE trending depocentre. The most southwesterly part of the plateau was interpreted by Eiken as being underlain by Tertiary volcanic crust, wheras the southeasternmost plateau is formed by older continental crust, as the seismic velocities and reflection characteristics are more varied. The Ocean Drilling Program investigated the plateau at Sites 910, 911 and 912 (Myhre, Thiede & Firth 1994). Each hole reached approximately 500 m below sea floor (mbsf) predominantly through homogeneous very dark grey silty clays and clayey silts, of Quaternary and Pliocene age. Two subunits were identified at each site on the basis of an uphole increase in dropstone abundance and size. The increase occurred at a depth of 208 mbsf at site 910, 380 mbsf at site 911 and 40 mbsf at site 912. Dropstones were most abundant at site 912 on the shallow SW edge of the plateau. They are mostly of siltstone, sandstone and mudstone composition, but igneous and metamorphic clasts were also present.

8.6.2

Fig. 8.12. Principal bathymetric features off northwest Spitsbergen (simplified from Eiken 1993).

The Yermak Plateau

Sjubrebanken

Sjubrebanken is a submarine bank in less than 200m of water, situated west of Albert I Land and north of Prins Karls Forland. Eiken (1993) presented seismic sections across the area, and identified a possible northward continuation of the Hornsund lineament. To the west of the lineament is a broadly westwarddipping sediment prism, with an approximate width of 140 km in the north and 110 km in the south, overlying volcanic basement. To the east of the lineament lies continental basement with graben structures; there is very little sediment cover in the southern part of the bank, but more in the north.

NORTHWESTERN SPITSBERGEN The seismic profiles reveal three sequences, YP-1, YP-2 and YP-3, all correlated with those on the Yermak Plateau (see above). The upper sequence (YP-3) has a depocentre on the outer shelf, from where it thins and downlaps to the west. YP-2 and YP-3 together are approximately 2 k m thick at their joint depocentre, where they form a 10km wide anticline showing a seismic crestal bright spot suggesting the presence of gas. The two sequences are probably of late Miocene to Plio-Pleistocene age.

8.6.3

Danskoya Basin

North of Sjubrebanken lies the Danskoya Basin. It is a 4-5 km thick trough-like sedimentary basin, oriented N-S and approximately 100 km by 20 km. Four sequences have been identified on seismic sections (Eiken 1993), designated DB-1 to DB-4. The major sequences are DB-1, 2 & 4 all of which onlap southwards. DB-3 contains thin progradational lenses. Most reflectors are truncated:

153

DB-1 by DB-2 to the south; DB-2 and DB-4 by the seafloor. Eiken explains this pattern by syn- and post-depositional uplift of N W Svalbard combined with subsidence of the basin.

8.6.4

Norskebanken

Situated due north of Spitsbergen, Norskebanken is the site of a basin with a 2-4 km thick sedimentary infill. The southern margin of the basin is marked by a north-throwing extensional fault (the Moffen fault), to the south of which lies Paleozoic rocks which continue onto onshore Spitsbergen. Eiken (1993) divided the sequence into a lower megasequences NB-1 and an upper sequence NB-2. NB-1 contains internal unconformities, interpreted by Eiken as the result of Cretaceous and Tertiary pre- and syn-rift movements. The megasequence is truncated at the outer shelf by NB-2, which is thought to consist of Miocene and younger strata. NB-2 was deposited rapidly with a depocentre at the outer shelf, and was related by Eiken to the uplift and glacial erosion of Svalbard.

Chapter 9 Central western Spitsbergen W. B R I A N

9.1 9.1.1 9.1.2 9.2 9.2.1 9.2.2 9.3

9.3.1 9.3.2 9.3.3 9.3.4 9.4 9.4.1 9.4.2 9.5 9.5.1 9.5.2 9.5.3 9.6 9.6.1

HARLAND

with contributions with ISOBEL

Paleogene rocks, 154 Kings Bay Coalfield (Ny-?desund), 154 Forlandsundet Graben, 157 Mesozoic strata of Oscar II Land, 158 Kapp Toscana Group, 158 Sassendalen Group, 159 Late Paleozoic strata of Oscar II Land (Biinsow Land Supergroup) (W.B.H., I.G. & R.A.D.), 159 Tempelfjorden Group, 159 Dickson Land Subgroup (Gipsdalen Group), 159 Charlesbreen Subgroup (Gipsdalen Group), 160 Billefjorden Group, 161 Early Paleozoic rocks, 162 Bullbreen Group, 162 Vestg6tabreen Complex, 164 Proterozoic strata of Oscar 1I Land, 165 Comfortlessbreen Group, 165 St Jonsfjorden Group, 165 Kongsvegen Group, 166 Pre-Carboniferous rocks of Prins Karls Forland, 166 Grampian Group (Early Paleozoic), 167

The West Spitsbergen Orogen extends along the western side of Spitsbergen from Kongsfjorden to Sorkapp. It is the product of the latest main deformation event in Svalbard (Spitsbergian) dated provisionally as Eocene. The deformation is of a compressive or transpressive nature associated with the dextral strike-slip displacement between Svalbard and Greenland through Cenozoic time. Within this fold and thrust belt earlier diastrophism is evident: Minor Late Cretaceous tilting with uplift took place. The main events were mid-Paleozoic. The mid-Paleozoic tectogenesis is commonly referred to as Caledonian. However the age of deformation appears to be mid-Ordovician rather than the typical mid-Silurian of the central and eastern terranes of Svalbard. To avoid confusion this is referred to as the Eidembreen teetogenesis (analogous with the M'Clintock Orogeny of northern Ellesmere Island). Some uncertainty must remain as to whether there was any Silurian diastrophism or more likely, late Devonian-Early Carboniferous tectonism to match the Ellesmerian events of Arctic Canada. The rocks divide naturally into younger (Carboniferous through Eocene) strata, i.e. post-Devonian, and pre-Devonian older rocks, there being no Devonian exposure within the orogen. Whereas the West Spitsbergen Orogeny was Paleogene (treated in Chapter 20) the orogen comprises the whole body of rock whether formed earlier or later. Because of the complex earlier history and variety of strata and structure along its length it is convenient to treat the structure in two parts, north and south of Isfjorden (Chapters 9 and 10 respectively). In this chapter the area treated comprises Oscar II Land and Prins Karls Forland (Figs 9.1 & 9.2). The eastern boundary remains indefinite and will overlap in treatment with chapter 4 because the younger rocks of the Central Basin extend westwards and the structure related to the orogenic compression extends far eastwards. The Carboniferous and Permian (Btinsow Land Supergroup) strata south of Isjforden in Nordenski61d Land are for convenience treated in this Chapter rather than in Chapter 10. Flood (1966) reported on mineralization especially in St Jonsfjorden where in 1919 and 1920 N.E. Co. prospectors set up Copper Camp on the south side of the fjord on the basis of chalcopyrite claims. Mineralization there has, however, not been exploited.

GEDDES

& PAUL

A. D O U B L E D A Y

9.6.2 9.6.3 9.6.4 9.6.5 9.6.6 9.7 9.7.1 9.7.2 9.7.3 9.7.4 9.8 9.8.1 9.8.2 9.8.3 9.8.4 9.8.5 9.9 9.9.1 9.9.2 9.9.3 9.10

Scotia Group (Late Vendian-Ediacara), 167 Peachflya Group, 167 Geikie Group, 167 Ferrier Group, 167 Pinkie Formation, 168 Structure of Oscar II Land (W.B.H. & P.A.D.), 168 Northwest Oscar II Land, 168 Southwest Oscar II Land, 168 Central and eastern Oscar II Land, 170 The St Jonsfjorden area, 171 Structure of Prins Karls Forland, 171 Sequence and age of deformation, 172 Vergence of deformation, 172 Faulting, 172 Metamorphic environments, 174 Conjectural synthesis, 175 Structure of the Forlandsundet Basin (W.B.H. & P.A.D.), 175 Structure of the infill, 175 Palaeostress history of Forlandsundet Basin (phases 1-3), 175 Origin of the Forlandsundet Basin: current models, 176 A tectonic interpretation of the West Spitsbergen Orogen; northern segment, 177

9.1

Paleogene rocks

9.1.!

Kings Bay Coalfield (Ny-~,lesund)

The previous published authority on this coalfield was by Orvin (1934). He described this Tertiary coal field in detail from surface and subsurface data. The rocks were given the name Ny-Alesnnd Formation by Challinor (1967); Orvin's two divisions were then described as members as follows.

(2) Green Sandstone Member (c. 100m). Quartz grains with a diameter of up to 0.5 mm constitute about one third of the rock. In addition grains of quartzite, shales, feldspar and marble occur, and are weathered brown from oxidation of pyrite. Sandy shales are rich in plant fossils- mainly tree leaves. No marine fossils have been recorded. About 35m from the base is the Ragnhild (coal) Seam and at the base is the Josefine Seam.

(1) Grey Sandstone Member (c. 95m). The upper 70m of this member is a pale sandstone, the top 20m of which contain conglomerates. Below this the Agnes Otelie Seam. The remainder of the formation comprises the 'Lower Coal Horizon', which is variable in sequence and thickness with the Advocat Seam at the top; 10 to 30 m below is the Sofie Seam and at the bottom (8-12 m below) is the Ester Seam which rests directly on the bottom shale. Owing to separation from other such strata in the Central Basin to the south, no precise correlation can be attempted. However, there are similarities with the Firkanten Formation (Paleocene) and the overlying Basilika formation of the Central Basin. Palynological and other evidence is consistent with this correlation. The formation overlies the Bottom Shale Formation (in the east of the coalfield) and oversteps it to the west onto the Kapp Starostin Formation. The history of mining and the sequel at Ny-,~lesund has been recorded by H a n o a (1993) with many personal and community details.

CENTRAL WESTERN SPITSBERGEN

155

Fig. 9.1. Topographic and place name map of Oscar II Land and Prins Karls Forland, based on Topographical Map o f Svalbard 1 ."500 000, sheets 1 and 3, Norsk Polarinstitutt.

The current classification of rock units a p p r o v e d by the SKS ( D a l l m a n n et al. 1995) (Fig. 9.3) combines elements o f Orvin (1934), C h a l l i n o r (1967) a n d Livshits (1974) as follows:

Van MijenfjordenGp Ny-Alesund Subgp (Challinor 1967; SKS 1995) BroggerbreenFm (Orvin 1934; SKS 1995) Bayelva Mbr (SKS 1995) Leirhaugen Mbr (SKS 1995) Kongsfjorden Fm (Orvin 1934; Livshits 1973; SKS 1995) TvillingvatnetMbr with M~rebekken conglomerate (SKS 1995) Kolhaugen Mbr (SKS 1995)

The Van Mijenfjorden Group was defined as combining the six Tertiary formations of the Central Basin, the lower two of which appear to correlate with the two of the Ny-Alesund Subgroup in spite of separation by the West Spitsbergen Orogen in Broggerhalvoya. The Ny-~i,lesund Subgroup is Challinor's (1967) Formation raised in rank so that his two members are raised to formation rank. The name Kongsfjorden Formation follows Livshits (1974) and the overlying Broggerbreen Formation was named by Livshits the Ny Alesund Formation but as that was already in use the new name was proposed by SKS (1995). Each pair of members proposed by SKS (1995) was based on unpublished work by Midboe, the only published detail on the coalfield

156

CHAPTER 9

Fig. 9.2. Diagrammatic outcrop map of central west Spitsbergen, based on various data from Harland, Hambrey & Waddams (1993), and SKS (Dallmann et al. 1996, fig. 3c),

CENTRAL WESTERN SPITSBERGEN

157

Fig. 9.3. Geological map and stratigraphic section of the Ny-~Jesund coalfields, redrawn from Orvin (1934) and from Midboe in SKS (Dallmann 1995, figs lb and 2b), with permission. since Orvin. The relevant detail appears in the SKS publication from which the following is taken. Broggerbreen Fm (Orvin 1934; SKS 1995) This is the Green Sandstone of Orvin (1934) and Green Sandstone Member of Challinor (1967) and has been recommended for division into two members by the Committee. It comprises conglomerates, sandstones, shales, coaly shales and coals. Bayelva Mbr, > 160 m the upper surface is truncated by a thrust surface: it consists of alternating conglomerates, sandstones, shales, coaly shales and coal seams of which the Josefine Seam is at the base of the Member with Ragnhild, KBI and KB seams higher up. Leirhaugen Mbr, 5-20 m consists of alternating conglomerates, sandstones, shales, coaly shales and the Agnes-Otelie coal seam at the base. It is distinguished because interpreted as transitional between the overlying continental unit and the underlying marine unit. Kongsfjorden Fm (Orvin 1934; Livshits 1974)= Grey Sandstone of Orvin (1934) and Grey Sandstone Member of Challinor (1967). Similary three members have been proposed. Tvillingvatnet Mbr, 15-70 m (SKS 1995 from Midboe unpublished). It is of coarse and medium grained marine bioturbated sandstone, pebbly sandstones and conglomerates resting with erosional unconformity on the Kolhaugen Mbr in the SE and on the Morebekken Mbr in the NW. Borehole log 38/76 shows only the upper part as conglomeratic and the lower part, sandy, pebbly and contorted. Morebekken Mbr, 10-20m (SKS 1995 from Midboe) consists of mainly coarse conglomerates with thin beds of coarse sandstone. The pebbles are of chert and glauconitic sandstone as from the underlying (Permian) Kapp Starostin Formation. Kolhaugen Mbr, 0-40m (SKS 1995 from Midboe) consists of rapidly alternating fine-grained sandstones, shales, coaly shales and coal with welldeveloped coal seams from the top: Advocaten seam, Sofie seam and Ester seam at the base of the member where the coaly beds rest directly on the (Early Triassic) Vardebukta Formation (Lower shale of Orvin 1934). It thins, as does the Vardebukta Formations to the west of the coalfield. 9.1.2

Forlandsundet Graben

The sedimentary strata appear in a scattered a r r a n g e m e n t dependent on the complex tectonic sequence of the G r a b e n which is

discussed in Chapter 20. The m o s t recent stratigraphic w o r k by RyeLarsen has only been partially published by SKS ( D a l l m a n n et al. 1995), which the notes below follow (Fig. 9.4). Despite the fragmentary nature of the stratigraphic evidence, a composite succession has been established that indicates an apparent thickness of as m u c h as 5 km. A l o n g the eastern and southwestern margins of the basin, alluvial-fan deposits are well d o c u m e n t e d . They are characterised by poorly sorted, unstratified conglomerate beds of debris-flow origin, and are associated with fine-grained, flat- and cross-stratified conglomerates originating as streamflow deposits (Steel et al. 1985). In the southwestern part of the area, the fan deposits apparently grade laterally (basinwards) into possible fandelta and nearshore deposits comprising a sequence of black shales, siltstones and cross-stratified or ripple-laminated sandstones. The northwestern region, with a succession 3 k m or m o r e thick, is

Atkinson1963

Livshits19671

SKS(Dallmannet al. 1995) basl~de?LaWsOrk by

Adoptedin thiswork (a possiblealternative) I KAFFI~YRACOMPLEX

McVitie (McVitiepynten) Fm

Selv~gen (conglomerate) Fm

AberdeenflyaFm MarchaislagunaFm KrokodillenFm ReinhardpyntenFm Sessh~gdaFm

r--

Ii

~ Balanus- SarstangenMbr ~

SarsbuktaMbr

I:Iil I I I

c.~ I ~ [ Kr~176 Fm ! ;~ ~o~-~1ReinhardpyntenFm !

Selv&genFm I! I I ~ ~ r J [ pyntenFm SarsbuktaMbr L /

AberdeenflyaFm

Fig. 9.4. Summary of the Paleogene stratigraphic units in Forlandsundet, modified from Rye-Larsen in SKS (Dallmann 1995, fig. 2c).

158

CHAPTER 9

characterised by black shales; associated turbidite a n d c o n g l o m e r a t e beds interpreted as a submarine-fan association. T h e marginal alluvial-fan sequences (e.g. Selvgtgen, Sarsbukta and Sarstangen formations) are laterally equivalent to the n e a r s h o r e and shallowm a r i n e deposits (Sesshogda, R e i n h a r d p y n t e n , K r o k o d i l l e n and M a r c h a i s l a g u n a formations) and to the s u b m a r i n e - f a n succession (Aberdeenflya F o r m a t i o n ) . The B u c h a n a n i s e n G r o u p was investigated by M a n u m (1962) and Livshits (1965, 1974) and E o c e n e to early Oligocene ages were obtained. M o r e recently, palynological dating on samples from the eastern m a r g i n o f the basin at Sarsbukta by M a n u m & T h r o n d s e n (1986), based on dinoflagellate studies, suggest a Late Eocene age, a l t h o u g h precise age constraints are n o t available (Kleinspehn & Teyssier 1992). C u r r e n t data therefore place the age of the F o r l a n d sundet G r o u p as Late Eocene to Late Oligocene (Feyling-Hanssen & Ulleberg 1984; Steel e t al. 1985).

Buchananisen Group (SKS 1995). This name replaces Forlandsundet Group (Harland 1969) which name is now restricted to the structural graben (Harland 1969). From seismic traverses at sea it is probably about 5 km thick. Balanuspynten Fm (SKS 1995)=Sars Fm (Atkinson 1963). Atkinson's name for the rocks on the east of the sound had priority before the rules for acceptance of names was laid down by the Committee. It conveniently combines the two members. Sarstangen Mbr (SKS 1995 from Rye-Larsen), 1050m in drill holes to metamorphic basement. It comprises fine to coarse-grained sandstones or conglomerates and siltstones. SarsbuktaMbr (SKS 1995 from Rye-Larsen unpublished) 600+ m with faulted contact to east and lower boundary not exposed consists of pebbly to boulder sized multicolored conglomerates with medium to coarse sandstones and rare thin siltstones. Coal and plant fragments are abundant. Feyling-Hanssen & Ulleberg (1984) suggested a mid- to late Oligocene foraminiferal age. Aberdeenflya Fm (SKS 1955 from Rye-Larsen) 2800+ m. Crops out on the northwest of the sound (northeast of the Prins Karls Forland) of alternating polymict, pebble-sized conglomerate and fine to medium-grained sandstones interbedded with siltstones and claystones. Horizontal burrows are common. Its stratigraphic relationships are not exposed. MeVitiepynten Subgp (Atkinson 1963). The following four units were named and described by Livshits (1967 and 1974) as formations and said to be equivalent to Atkinson's McVitiepynten Formation. It crops out on the west of the sound. Marchaislaguna Fm (Marchais Fm of Livshits 1967) 55 to 600+m of alternating polymict, stratified, grey to yellowish, pebble-sized conglomerates and medium-grained sandstones with siltstones and claystones with S k o lithos, Arenicolites and Diplocraterion burrows. There is a sharp, possibly erosive, boundary with the underlying member. Krokodillen Fm, 400+ m of dark silty claystones interbedded with 2 40 m thick light fine grained sandstones rests directly on Selvgtgen Fm to W and contact with the Reinhardpynten Mbr is not exposed. Reinhardpynten Fro, 210+ m of dark clay-stones, with carbonate concretions and quartzite lonestones, coarsening down to very fine sandstones and siltstones with pyrite and siderite concretions. Sesshagda Fm, >120 m of light grey medium to coarse-grained conglomeratic sandstones alternating with siltstones and clay stones in the lower part with sideritic concretions and pyrite in the upper part. The lower boundary is gradational. Selvfigen Fm (Atkinson 1963; Livshits 1972, 1974) 40 170m of pebbly to boulder-size greenish grey to yellow and red conglomerates and breccias near the graben faults from which they thin to the east. Rests with angular unconformity on the Vendian Scotia Group of Prins Karls Forland. Katfiayra Complex. The scattered exposures through much of the eastern flatland of Sarsoyra and the hills to the east, as well as the similar coastal flat of Kaffioyra to the south, have long been a puzzle because of their incoherent and disjointed arrangement. From successive short visits up to 1992 by the Cambridge group a (dextral) strike-slip melange was inferred. However Ohta, Krasil'shchikov e t aL (1995) not only detailed such a strikeslip shear zone but from petrogenetic and geochemical studies identified low-temperature, high-pressure metamorphic rocks. These green-brown dolostones and serpentinites match those of the Vestg6tabreen (?subduction) Complex at Motalafjella to the south. The Motalafjella rocks are described below (Section 4.2) where an Ordovician metamorphic age is generally accepted. The Kaffioyra Complex appears to have been part of the Vestg6tabreen Complex, but involved in Paleogene dextral shear and so forms a shear zone north of Motalafjella and Ankerfjella. The Complex is

thus (Spitsbergian) Paleogene, the original metamorphism was Ordovician, but the protoliths were probably basic volcanics in the Lovliebreen Formation of the St Jonsfjorden Group argued here (as by Harland, Hambrey & Waddams 1993) to be Early Varanger in age. Ohta et al. were of the same opinion except that they stated a middle Proterozoic age for the same rocks. A distinct facies is the green-brown dolostone, which is a magnesite rock with fuchsite, accessory chromite and chromium spinel. They are, as at Motalafjella, associated with tectonic blocks of serpentinite. Geochemical analyses confirm these affinities. Larger units have been juxtaposed in a zone to the east of the Kaffioyra Complex. From the investigations of Ohta et al. (1995), they also correlate with the Ordovician rocks south of St Jonsfjorden. In particular, the Aavatsmarkbreen Formation, taken to lie at the top of the Vendian sequence in the Comfortlessbreen Group, should belong to the Bullbreen Group. The Sarsoyra Formation is exposed as a series of white carbonate hills to the northeast of Sarsoyra. In a conglomerate clast W. T. Horsfield found a rugose coral and Scrutton, Horsfield & Harland (1976) took this to correlate with the Bulltinden Formation of ?Silurian age. Because the poorly preserved coral could equally have been Carboniferous, the age of the Sarsoyra Formation was in doubt and possibly late Paleozoic. However, the Makarjev's work reported by Ohta et al. (1995) confirms the original opinion of Scrutton et al. (1976). The Aavatsmarkbreen and Sarsoyra formations are coherent bodies within the Paleogene transpression complex so in themselves cannot be regarded as Paleogene; but they are integral parts of the graben structure. The Pinkie Formation or Complex, referred to in Section 9.6.6, has been taken as possibly the oldest part of the Prins Karls Forland sequence. It is an allochthonous thrust unit and was thought to have derived from a similar basic volcanic protolith of Early Varanger age (Harland et al. 1993). Ohta et al. (1995) also relate this to the same material, but whether it is related to a Paleogene shear zone is another matter.

9.2

Mesozoic strata of Oscar II Land

Cretaceous and Jurassic outcrops are limited to two areas on the northwest coast o f Isfjorden where they complete the n o r t h e r n frame of the Central Basin underlying the Paleogene elliptical brachysyncline. T h e y are a m a j o r consideration in C h a p t e r 4 and are omitted here. Triassic strata extend from n o r t h to south of Oscar II L a n d and are intimately involved in the fold and thrust belt o f the West Spitsbergen Orogen. The i n c o m p e t e n t Triassic shales o f the Sassendalen G r o u p dramatise the fold and thrust structures with the contrasting c o m p e t e n t K a p p Starostin F o r m a t i o n . Before the Paleogene o r o g e n y the upper Triassic units h a d already been progressively e r o d e d towards the n o r t h so that within a distance o f 100km from Selmaneset in the south to NyAlesund in the north the whole remaining Mesozoic succession was reduced to zero thickness beneath the overstepping Paleocene strata. With the loss of Cretaceous and Jurassic strata just n o r t h of Isfjorden the Triassic succession was reduced to 725m at Iskletten (without the K a p p Starostin G r o u p and the u p p e r m o s t Botneheia F o r m a t i o n ) . Southeast o f N y - A l e s u n d the V a r d e b u k t a F o r m a t i o n (Bottom Shale of Orvin 1934) is only 50 m and to the n o r t h w e s t of the coalfield Paleogene strata rest directly on P e r m i a n rocks. This section of the chapter in effect treats mainly the Sassendalen G r o u p defined by the three formations: Botneheia, Sticky K e e p and V a r d e b u k t a .

9.2.1

Kapp Toscana Group

Occurs only in southern Oscar II L a n d with a m a x i m u m thickness of a b o u t 200 m. The D e G e e r d a l e n F o r m a t i o n is of typical greenish-grey sandstones and siltstones a n d with no Tschermakfjellet F o r m a t i o n facies between it a n d the underlying Botneheia Formation.

CENTRAL WESTERN SPITSBERGEN

9.2.2

Sassendalen Group

T h e g r o u p as a whole thickens westwards a n d s o u t h w a r d s in Oscar II L a n d t o w a r d s a m a x i m u m exposed thickness between Isfjorden and Bellsund (Buchan et al. 1965). The thickening is related to a s o m e w h a t coarser grain size which led M o r k et al. (1982) to p r o p o s e a distinct n o m e n c l a t u r e for the western succession. This was partly based on the a s s u m p t i o n of a sharp increase in thickness to the west o f a postulated N - S fault. H o w e v e r , the intermediate Oscar II L a n d thicknesses of the g r o u p also fit a gradual increase in thicknesses which f r o m Sveaneset to Festningen is a b o u t from 400 to 820 m over a distance of a b o u t 55 k m as seen in the fence d i a g r a m o f B u c h a n et al. whose same three constituent f o r m a t i o n s can be recognized t h r o u g h o u t Spitsbergen as confirmed by Worsley & M o r k (1978). The Botneheia Fm, 262m in southern Oscar II Land, occurs only in southern Oscar II Land. It is characterized by laminated dark shales, often bituminous. The silty to sandy facies may be characterized by phosphatised burrow infills. The coarser facies tend to increase upwards with ripple cross lamination and with both calcareous and phosphatic cement. At Sveaneset it yields Gymnotoceras, Posidonia and Daonella f r a m i which may be more characteristic of the lower horizon. Mork, Knarud & Worsley (1982 et seq) and some later publications refer to this formation by the name Bravaisberget for the somewhat coarser and thicker facies southwest of Isfjorden. The Sticky KeepFm, 230 m at Iskletten, is a coarser unit than the Botneheia Formation. The unit also tends to coarsen upwards. In Oscar II Land this has led to a division into two members of the original Sticky Keep Fm. Kaosfjellet Mbr is a distinctive cliff-forming unit of yellow to brown weathering, laminated, shaly siltstones alternating with harder more calcareous siltstones. This competence contrast may promote small scale chevron folding, hence the name of the unit. Isldetten Mbr is a more shaly unit and typically with grey septarian limestone concretions. The Sticky Keep Fm has been referred to in the west, south of Isfjorden as the Tvillingodden Fm (Mork et al. 1982). The Vardebukta Fm, 253 m. This unit was defined in the Festningen section south of Isfjorden. At Selmaneset it is 258 m. The formation is typical of sandstones to siltstones with interbedded shales. As with the two higher formations the coarser facies predominate in the upper part which has led to the division of the formation into two members (Buchan et al. 1965). Siksaken Mbr, c. 100 m comprises alternating grey calcareous siltstones and silty limestones passing to calcarenite, light grey and white sandstones, hard siltstones and calcareous shales. Selmaneset Mbr, c. 150 m comprises somewhat softer dark grey, often calcareous, silty shales with thin hard calcareous siltstones interbeds, sandier towards the top with clay-ironstone concretions. Fossils are few. The lower boundary with the Permian Kapp Starostin Fm is conspicuous. The Bottom Shale of Orvin (1934) in the Ny-~,lesund coalfield= Vardebukta Fro, 0-50m of Challinor (1967). This formation is thickest in the east of the coalfield, where it underlies the Kongsfjorden Formation. It is overstepped in the west. Exposure is limited to a few gully sections, and the main information derives from drill cores. No fossils have been recorded. The upper part is distinguished by variable green, brown and red shales and claystones with conglomerate. Orvin (1934) suggested that it had been derived by erosion of rocks equivalent to the lower part. The lower part is of more uniform shale and is characterised by basal breccias and limestone. The breccias are clearly derived from the cherts of the underlying (Zechstein) Kapp Starostin Formation. Although Orvin postulated a Cretaceous age, the Early Triassic (Scythian) age accepted here is based on lithological correlation (Challinor 1967) with the Vardebukta Formation of the Central Basin (defined at Festningen). It is also consistent with the generalisation by Challinor (Buchan et al. 1965, p. 50) that in Oscar II Land the Triassic strata progressively lose their higher units from south to north.

9.3

Late Paleozoic strata of Oscar II Land (Biinsow Land Supergroup)

Late Paleozoic rocks in this part of Spitsbergen occur in two belts (Fig. 9.2). The m a i n exposures of P e r m i a n rocks are in Broggerh a l v o y a a n d a line extending southeastwards to E k m a n f j o r d e n and

159

N o r d f j o r d e n . A less extensive zone occurs within the Tertiary folda n d - t h r u s t belt, with exposures of C a r b o n i f e r o u s a n d P e r m i a n rocks trending roughly N-S from the eastern end of St J o n s f j o r d e n south to T r y g g h a m n a / Y m e r b u k t a on the n o r t h side of Isfjorden, a n d thence into Nordenski61d L a n d at Festningen ( K a p p Starostin). T h e section at Festningen affords almost complete exposure o f strata f r o m Early C a r b o n i f e r o u s t h r o u g h Early Cretaceous. A d v a n t a g e of this was taken by earlier workers which resulted in the s t a n d a r d stratigraphic description for those intervals in Svalbard. The section was described a n d m e a s u r e d in great detail by H o e l & Orvin (1937). As the n o m e n c l a t u r e used there is the same as for Oscar II L a n d , but different f r o m that in southern Spitsbergen, the Late Paleozoic rocks o f Nordenski61d L a n d will be treated here r a t h e r t h a n in C h a p t e r 10. T h e lower part o f the Gipsdalen G r o u p (approximately Carboniferous) is k n o w n mainly from B r o g g e r h a l v o y a a n d southwestern Oscar II L a n d (St J o n s f j o r d e n a n d T r y g g h a m n a areas). As n o c o m m o n stratigraphic names have been applied across the region, each area is described separately.

9.3.1

Tempelfjorden Group

Kapp Starostin Formation. This f o r m a t i o n is approximately 200 m thick in Oscar II L a n d (Fig. 9.2), w h e r e it is similar to exposures further east. It contains u n i f o r m siliceous limestones and cherts and a rich b r a c h i o p o d a n d b r y o z o a n fauna. H o w e v e r , it is typically s a n d y a n d glauconitic at the top as elsewhere.

9.3.2

Dickson Land Subgroup (Gipsdalen Group)

This u p p e r part of the Gipsdalen G r o u p as defined in the Central Basin ( C h a p t e r 4) represents a laterally extensive depositional unit covering central a n d western Spitsbergen. Exposures in Oscar II L a n d are b r o a d l y similar to those in central Spitsbergen. It comprises two formations.

Gipshuken Formation. The G i p s h u k e n F o r m a t i o n is approxim a t e l y 146m thick w h e r e it is exposed on B r o g g e r h a l v o y a (Fig. 9.1). T w o m e m b e r s are recognized (at Ny-Alesund): an upper dolostone member (60 m) and a (lower) Kloten Breccia (80 m). The latter is u n i f o r m a n d extensive, and p r o b a b l y resulted f r o m solution collapse at the edge o f a large evaporate basin lying to the southeast, as at G i p s h u k e n itself. W o r d i e k a m m e n Formation. The f o r m a t i o n comprises two m e m bers in Oscar II L a n d (the same u p p e r two m e m b e r s of the replaced Nordenski61dbreen F o r m a t i o n ) . Tyrrellfjellet Mbr, Cutbill & Challinor (1965) described three units in this member. At the top the Ki~rfjelletBeds which are approximately equivalent to limestone B (now Finlayfjellet Beds) of the Central Basin. It is of incompetent thinly-bedded to laminated dolostones. The middle unit is an unnamed dolostone sequence; and the lower unit is the Brucebyen Beds - a bituminous fusuline coquina overlying sandy limestones with a thin conglomerate (up to 8 m) at its base. A local unconformity cuts out the Brucebyen Beds at Scheteligfjellet. The MorebreenMbr 115 140 m of Cutbill & Challinor (1965) is equivalent to the Cadellfjellet Formation. Up to 140 m thick on Broggerhalvoya, it consists equally of interbedded dolostones and limestones. Deposition probably occurred on a quiet marine shelf with high salinity. Although no macro fossils have been recorded, fusulinids indicate a Late Moscovian-Gzelian age. No lithological subdivision is possible, but the Gerritbreen and Jotunfonna beds present to the east can be traced on the basis of fusulinid zonation. The topmost beds contain Waeringella usvae zone fossils of Gzelian age. The dolostone is buff-coloured, generally thick-bedded, blocky and with a micritic or silty texture. It commonly contains nodules of chert. Grey limestones occur interbedded with the dolostones. They are generally fairly pure biomicrites with abundant fusulinids and bryozoans, but no macrofossils. Beds are occasionally sandy at the base and chert nodules are common. Massive beds of grey, poorly bedded, stylolitic micrite occur at the top of the formation in the north of Broggerhalvoya. Faunas and age. Two sets of beds were distinguished on the basis of fusulinid zones further east by Cutbill & Challinor.

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The Gerritbreen Beds. These are carbonates containing the W. usvae zone fauna, occurring at the top of the formation in Broggerhalvoya, where they are about 83 m thick. They pass laterally onto the Nordfjorden Block with some thinning and form part of the Kapitol Member. Within the St Jonsfjorden Trough, the beds are cut out rapidly to the south by the Permian unconformity and at St Jonsfjorden, the Permian Tyrrellfjellet Fm rests directly on the TSrnkanten Fm. The Jotunfonna Beds. These are distinguished by the presence of the earlier Wedekindellina zone fauna and are about 60m thick in Broggerhalvoya. They thin slightly to the east and pass laterally into the Kapitol Mbr. They are also cut out to the south by the basal Permian unconformity. No benthic macrofauna has been recorded, only bryozoans and foraminifers. Cutbill (pers. comm.) listed the following: upper W. usvae zone (Gzelian) species from the top of the formation at Scheteligfjellet: Waeringella usvae, Quasifusulina longissima, Triticites sp. A, 'Schubertella' sp., Montiparus montiparus, Protricitites ovatus, Pseudoendothyra sp. Other species, representative of the lower W. usvae zone (Kasimovian) and the upper Wedekindellina zone (Late Moscovian), occur lower down in the unit. The Morebreen Mbr can therefore be correlated with the Jotunfonna and Gerritbreen beds in Billefjorden, as well as the lower part of the Kapitol Mbr of the Nordfjorden Block. The W. usvae zone correlates with the Gzelian and Kasimovian stages of the Russian Platform, so the unit is of Late Moscovian-Gzelian age.

9.3.3

Charlesbreen Subgroup (Gipsdalen Group)

This c o m p r i s e s the lower f o r m a t i o n s o f the G i p s d a l e n G r o u p in the west (Fig. 9.2) a n d is a p p r o x i m a t e l y e q u i v a l e n t to the C a m p bellryggen S u b g r o u p o f the C e n t r a l Basin. A C h a r l e s b r e e n G r o u p was i n t r o d u c e d by Dineley (1958) for the St J o n s f j o r d e n strata a n d was e x t e n d e d also to include the B r o g g e r h a l v o y a f o r m a t i o n s as a s u b g r o u p by S K S (1996). It c o m p r i s e s two pairs o f e q u i v a l e n t f o r m a t i o n s thus:

St Jonsfjorden and Isfjorden T~rnkanten Fm Petrellskaret F m

Broggerhalvoya Scheteligfjellet F m Broggertinden Fm

Scheteligfjellet Formation. This f o r m a t i o n consists o f c a r b o n a t e s , calcareous s a n d s t o n e s a n d c o n g l o m e r a t e s f o r m i n g sequences u p to 150 m thick (Fig. 9.5). It was d e p o s i t e d in Early to M i d - M o s c o v i a n time, a n d represents a m a r i n e transgression over terrestrial rocks o f the B r o g g e r t i n d e n F o r m a t i o n a n d Billefjorden G r o u p . It c o n t a i n s a varied f a u n a i n c l u d i n g fish remains. Definition. The Scheteligfjellet Fm is a distinctive 150m thick unit recognized only in western Broggerhalvoya. It is cut out eastwards by the Pretender Fault. Gobbett (1963) introduced the term Scheteligfjellet Beds for the Middle Carboniferous strata lying beneath the Cyathophyllum Limestone. Cutbiil & Challinor (1965) redefined the Scheteligfjellet Mbr as part of the Nordenski61dbreen Fm occurring only in Broggerhalvoya and coeval with the T~rnkanten Fm of Central Oscar II Land. Their member is here

Fig. 9.5. Fence diagram show the stratigraphic relationships within the St Jonsfjorden Trough (From Cutbill & Challinor 1965).

upgraded to formation status in line with the replacement of the Nordenski61dbreen Fm. The 'Leinstranda Fm' described by Barbaroux (1968) is probably equivalent to the Scheteligfjellet Fm. The type section is at Scheteligfjellet. The formation lies conformably beneath the Jotunfonna Beds of the Morebreen Mbr, the top being marked by a downward passage from rather pure carbonates to interbedded cherty carbonates, calcareous sandstone and some conglomerates which are red in part. The lower boundary is an unconformity marked by a basal conglomerate. It overlies Billefjorden Gp sediments to the west of the Kvadehuken Fault, and the red clastics of the Broggertinden Fm to its east. Lithologies. The formation comprises a distinctive, but somewhat heterogeneous, unit of carbonates, calcareous sandstones and breccias, with a basal conglomerate. Shelf carbonates make up the bulk of the formation (75%). They are generally grey or dark grey micrites or biomicrites, commonly with interbedded calcareous sandstones. Holliday (1968) noted a ~ 3 m coral biostrome occurring locally above the basal conglomerate: it is almost completely dominated by the species Chaetetes radians Fischer and Campophyllum kiaeri Holtedahl, with rare Syringopora sp., which are usually in positions of growth and built on top of each other (this is the 'coral limestone' of Holtedahl 1913). On Ki~erfjellet and northern Kulmodden, the formation contains breccias up to 50 m thick, comprising fragments of grey and yellow-weathering dolostone and limestone up to 10 cm across. The mass splits into several layers when traced laterally. The breccias are probably of intraformational origin, formed by erosion of the underlying beds, but a solution mechanism cannot be ruled out. Greenish-grey or reddish calcareous sandstone interbeds are the distinctive feature of the formation and occur throughout, making up 15% of the total. Red and green shales and siltstones occur with sandstones near the base of the formation. The base of the formation is marked by a conglomerate 0 8 m thick, that fills in topographic irregularities in the pre-Moscovian surface. It is largely quartzose, but with more variable clasts than the underlying Billefjorden Group conglomerates, with indications of channelling and reworking of sediments. Beds and lenses of black laminated limestones, red shales and red or green sandstones occur. The matrix is calcareous and shows signs of algal binding (Holliday, 1968). Palaeontology and age. The formation contains an abundant marine fauna, including brachiopods, fusulinids, corals, crinoids, bryozoans, gastropods, trilobites and fish. Holtedahl (1911, 1913) first described a rich Moscovian fauna from Braggerhalvaya, collected from limestones and conglomerates at the base of the formation. The brachiopod fauna is of general 'Middle Carboniferous' character and resembles that of the Minkinfjellet Mbr in Billefjorden and the TSrnkanten Fm of St Jonsfjorden (Gobbett 1963). The fusulinids are typical of the Wedekindellina zone in the upper part of the member and the Profusulinella zone lower down as defined by Cutbill & Challinor (1965). This implies an Early to Mid-Moscovian age for the formation, and strongly supports the correlation with the Minkinfjellet Fm.

Braggertinden Formation, 350 m. T h e B r o g g e r t i n d e n F o r m a t i o n is a variable sequence o f s a n d s t o n e s , c o n g l o m e r a t e s a n d c a r b o n a t e s f r o m B r o g g e r h a l v o y a a n d n o r t h e r n Oscar II L a n d (Fig. 9.3). It is correlated with the E b b a d a l e n F o r m a t i o n o f the Billefjorden area (Cutbill & C h a l l i n o r 1965). It occurs only to the east o f the K v a d e h u k e n Fault. T h e s a n d s t o n e s are generally flaggy a n d micaceous, a n d are o f variable c o l o u r f r o m red a n d b r o w n to yellow. I r o n is c o m m o n a l t h o u g h i r o n s t o n e b a n d s are rare. D e p o s i t i o n p r o b a b l y o c c u r r e d in a fluvial e n v i r o n m e n t . N o m a r i n e f a u n a have been r e c o v e r e d a n d the o t h e r f a u n a (including fish remains) are n o t age-diagnostic. H o w e v e r , the f o r m a t i o n is generally r e g a r d e d as being o f B a s h k i r i a n age. Definition. The formation is well exposed at several localities on Broggerhalvoya. The type section is at Broggertinden, where it is 361 m thick. The formation is absent to the west of the Kvadehuken Fault, where Billefjorden Gp sandstones occupy an analogous position. The formation lies concordantly beneath limestones of the Scheteligfjellet Mbr. The boundary is an unconformity marked by the basal conglomerate of the overlying member, dividing the largely carbonate lithologies above from arenaceous ones below. The base is marked by a sharp unconformity, overlying pre-Devonian mica-schists. Nowhere does the formation rest on Early Carboniferous Billefjorden Gp strata, which are present in Broggerhalvoya only to the west of the Kvadehuken Fault.

C E N T R A L WESTERN SPITSBERGEN Two lithological units are present in the type section at Broggertinden. The Upper Mbr, about 185m thick, comprises sandstones with conglomerates and rare limestones, e.g. at Ki~erfjellet. The Lower Mbr consists of about 163 m of conglomerates with few finergrained interbeds. Lithologies. The formation consists predominantly of sandstones (45%) and conglomerates (45%). Fine, medium and coarse-grained sandstones occur throughout the formation, interbedded with the conglomerates. They are commonly flaggy and micaceous, in places shaly. Iron is abundant, and hematite cement occurs in some beds. They are generally red or brown, but white and grey beds are found. Yellow, red and brown conglomerates occur throughout, predominating in the lower part. Clasts are rounded and 2-3 cm across. They consist of quartzite and chert derived either from pre-Devonian rocks or secondarily from the Orustdalen Formation. The matrix is sandy. Red shales occur interbedded with the sandstones and conglomerates. A thin ironstone occurs near the top of the formation at Broggertinden. At Kia~rfjellet, the middle of the upper part contains yellow shaley dolomites, conglomeratic limestones and grey, blocky calcarenite. One such carbonate bed contains rare fossils. Palaeontology and age. Poorly preserved fish fragments were found in the sandstones in the Scheteligfjellet section by Orvin (1934) who first supposed a Devonian age; otherwise the clastic facies appears to be unfossiliferous. The limestones on Kia~rfjellet contain poorly preserved brachiopods, crinoids and fusulinids which are certainly of Carboniferous age. Thiedig (1988) reported mid-Carboniferous microfossils in limestones associated with the red beds. As the formation lies below the Moscovian Scheteligfjellet Member and resembles facies of the Ebbadalen Formation it is assumed to be of Bashkirian age.

Tfirnkanten Formation. P r e s e n t along the I s f j o r d e n c o a s t o f Oscar II L a n d , the Tgtrnkanten F o r m a t i o n is a u n i t u p to 250 m thick o f m a i n l y q u a r t z arenites w i t h m i n o r c o n g l o m e r a t e , shale a n d limestone. C a l c a r e o u s n o d u l e s a n d desiccation cracks c a n be o b s e r v e d in places, a n d the s a n d s t o n e s are c o m m o n l y r e d d e n e d . T h e limestone b a n d s c o n t a i n a varied f a u n a w h i c h indicates Early a n d M i d - M o s c o v i a n ages. D e p o s i t i o n was w i t h i n a c o a s t a l / i n t e r t i d a l e n v i r o n m e n t w i t h b o t h fluvial a n d m a r i n e c o n d i t i o n s represented. Definition. Dineley (1958), in his description of the 'Charlesbreen Group', distinguished the higher red sandstone and conglomerate unit as the Tfirnkanten Sandstone. It was defined as The Tgtrnkanten Fm by Cutbill & Challinor (1965). The formation is the lateral equivalent of the Scheteligfjellet Fm of Broggerhalvoya (see above). The type section is on Tfirnkanten, where the formation is 251 m thick. The sequence reappears in the south of Oscar II Land at Trygghamna and south of Isfjorden at Orustdalen where 253 m are present below the Permian Tyrrellfjellet Mbr. Further south in Bellsund, the formation is cut out by prePermian erosion and the Tyrrellfjellet Mbr limestones rest directly on Early Carboniferous Billefjorden Gp sandstones of the Vegard and Orustdalen fms. The upper boundary is an unconformity beneath the Permian Wordiekammen Fm limestones which appear to cut down into the T~trnkanten Fm sandstones. These have been leached at the top and bright yellow limonite coats the bedding surfaces and joints. The lower boundary is at the base of the lowest massive sandstones under which lie the soft red shales of the Petrelskaret Fro. Lithologies and division. The formation consists of arenites (80%), conglomerates (5%), thin shales (10%) and limestones (5%). Massive, mature quartzose red and white coloured sandstones and grits, which are quartzitic or calcareous in places, form the bulk of the formation. Feldspar is rare. Cross-bedding is common, generally on a small scale, with foresets inclined at a low angle. Asymmetrical and oscillation ripple marks also occur, but there appears to be no preferred orientation. There is syn-sedimentary contortion near the top of some sandstone beds. The sandstones have sharp bases, and commonly grade upwards into finer sediments. The beds are occasionally conglomeratic at the base, with vein-quartz pebbles. Intraformational conglomerates are common, and may also contain rolled fossils. Thin marls or shales of a variety of colours occur regularly interbedded with the sandstones. They often contain small calcareous nodules scattered in bands. Polygonal desiccation cracks commonly affect the thin shales between the sandstone beds, ranging in diameter from 2-30 cm and penetrating downwards for up to 60 cm. There are several bands of thin grey limestone, commonly containing marine fossils, in the middle and upper part of the formation. They contain varying amounts of silt and sand and in places grade into coarse sandstone. Dineley & Garrett (pets. comm.) have recognized three major cyclothems within the formation at St Jonsfjorden, separated by two distinct

161

marine bands. At the base of each are massive quartzites which are overlain by calcareous grits and sandstones, conglomerates and thin shales with a marine band at the top. The latter is several metres thick and consists of poorly sorted sandstone with trace fossils which passes upwards into shale followed by limestone with marine fossils, then more shale then finally finegrained sandstone. The upper cyclothem is incomplete, and is represented by the highest massive and thin-bedded quartzites with thin red and brown shales exposed beneath the Permian unconformity. It has the Tfirnkanten marine band (c. 4 m thick) at its top, below which lie about 21 m of mottled calcareous sandstones and conglomerates containing at least one fossiliferous sandy limestone. These are underlain by a 44 m thick unit of massive red and white quartzose sandstones and quartzites. The lower cyclothem is similar: its top is defined by the fossiliferous Robertsonfjellet marine band (7.5 m), underlain by 20m of calcareous sandstone and 68m of red calcareous and quartzose grits, with massive red and white quartzites at the base. Palaeontology and age. varied marine faunas are common in the limestones, especially in the upper part of the formation. The faunas of the two marine bands are distinctive and consist predominantly of one species of brachiopod (a spiriferid in the Robertsonfjellet marine band and a large chonetid in the T~rnkanten marine band), with other brachiopods, crinoid ossicles, echinoid spines and rare coral fragments, trilobites and molluscs. Other limestone beds yield corals, brachiopods and crinoids. Rare lingulids are present at some horizons and fragmentary plant remains occur locally. The brachiopods compare closely with those of the Scheteligfjellet Formation of Broggerhalvoya (Gobbett 1963; Dineley & Garrett 1950, and CSE), suggesting that the unit is probably of Early and Mid-Moscovian age.

PetreHskaret Formation, 350 m. This f o r m a t i o n consists m a i n l y o f shales a n d m u d s t o n e s , c o m m o n l y p u r p l e in c o l o u r b u t also black a n d even b i t u m i n o u s in places. Also p r e s e n t are t h i n s a n d s t o n e interbeds, i r o n s t o n e b a n d s a n d rare e v a p o r i t e beds. T h e age o f the f o r m a t i o n is e s t i m a t e d as Bashkirian, a l t h o u g h the f a u n a is very sparse. D e p o s i t i o n was o n a coastal alluvial plain, m a i n l y fluvial or lacustrine b u t with a m a r i n e influence, especially early o n w h e n m o s t o f the l i m e s t o n e s a n d evaporites were f o r m e d . Definition. The Petrellskaret Fm is a sequence of shales having limited outcrop in Oscar II Land. It was originally described by Dineley (in Gobbett 1963) from St Jonsfjorden. Cutbill & Challinor (1965) gave it formational status and correlated it with the Broggertinden Formation. The type section is on Petrelskardet, St Jonsfjorden (Fig. 9.5). It is present at Orustdalen south of Isfjorden, but is absent around Bellsund owing to Permian erosion. The upper boundary is conformable, at the base of the massive quartzites of the TArnkanten Fm. The base is conformable and marked by a group of hard sandstones, silicified limestones, shales and evaporites 12.5 m thick, below which are dark shales and grey sandstones of the Vegard Fm (Billefjorden Gp). Lithologies. The bulk of the formation (80%) is composed of shales and laminated mudstones, generally purple, but in places black and bituminous, especially in the upper part, where conspicuous bands of ironstone are found. A remani6 band of ferruginous grit, 23 m thick, containing phosphatic nodules, clay pellets, rare quartz pebbles, fish scales, bones and teeth occurs near the top of the formation. There are thin sandstone interbeds, with rare intraformational conglomerates. The shales are occasionally marly towards the base of the formation and calcareous nodules occur. At the base are grey silicified limestones and evaporites interbedded with hard sandstones and shales. Light-coloured sandstone beds, generally quite thin, occur throughout, forming about 15% of the formation. They are sharply defined, commonly with erosive bases and are irregular in thickness or lenticular. They become finer upwards. Clay intraclasts are locally present in the basal layers. A thick white quartzite occurs 90 m below the top. Evaporites are a minor constituent of the sequence, occurring as thin intercalations at the base and as a gypsum band about 65 m below the top. Palaeontology and age. Fossils are rare in this formation. On Petrellskaret, indeterminate corals, resembling cyathophyllids and ?Syringoporaare found in the limestones near the base, and fish scales, bones and teeth occur in the remani6 grit near the top. As the formation lies below sediments of Moscovian age and above the Serpukhovian Vegard Fm, it is probably of Bashkirian age. 9.3.4

Billefjorden Group

T h e Billefjorden G r o u p in w e s t e r n Spitsbergen consists o f the V e g a r d a n d O r u s t d a l e n f o r m a t i o n s , u p to 1 1 2 0 m thick, d e p o s i t e d

162

CHAPTER 9

in the St J o n s f j o r d e n T r o u g h , w h i c h appears to have been isolated f r o m the rest of Svalbard in Early C a r b o n i f e r o u s time. P r e - P e r m i a n uplift a n d erosion has r e m o v e d some of the V e g a r d F o r m a t i o n and later C a r b o n i f e r o u s sediments in m a n y areas. The full extent of the t r o u g h is not known; but it stretched, at least, f r o m B r o g g e r h a l v o y a to Bellsund The eastern m a r g i n was the N o r d fjorden Block. T w o f o r m a t i o n s were recognized in western Spitsbergen by Cutbill & Challinor (1965) in the Culm of N a t h o r s t (1914; 1920), H o l t e d a h l (1912) and Orvin (1940). These are the (upper) Vegard F o r m a t i o n , consisting of thinly-bedded sandstones and shales; a n d the (lower) O r u s t d a l e n F o r m a t i o n o f coarse sandstones and conglomerates.

Vegard Formation, 358 m. The V e g a r d F o r m a t i o n consists of sandstones with c a r b o n a c e o u s shales a n d subordinate conglomerate. It is a fluvial unit o f p o o r l y constrained age as f a u n a are sparse, but it is generally regarded as Serpukhovian. Definition. This is a formation of sandstones and shales which is 358 m thick in the type section in Orustdalen in Nordenski61d Land. It was first described in Oscar II Land by Dineley (1958), who divided the 'Culm' into two formations. Cutbill & Challinor (1965) extended this upper formation southwards to Nordenski61d Land, where maximum thicknesses occur. The upper boundary in the type section is sharp, but conformable, and is marked by an abrupt upward lithological change from sandstones with interbedded shales to the beds of the basal Petrellskaret Fm (Gipsdalen Gp). The latter consists, at its base, of silicified limestones and evaporites interbedded with hard sandstones and shales (see above). Elsewhere, however, later Carboniferous erosion has resulted in removal of the top of the formation and an unconformity with the Permian Wordiekammen Fm limestones. The base is conformable above massive sandstones of the Orustdalen Fm. Lithologies. Light grey, white and locally reddish, thinly-bedded/flaggy or blocky sandstones are interbedded with dark grey-black carbonaceous shales. The sandstones are generally fine-medium grained, but occasionally coarse-grained, and there are local conglomerate horizons and lenses. Poorly-preserved plant remains are common in both sandstones and shales; the latter may be coaly. Palaeontology and age. Nathorst (1914), in his studies of the Billcfjorden Group, included detailed lists of plants from the 'Culm' of western Spitsbergen. Although the Vegard and Orustdalen fins were not differentiated, on the basis of locality the stratigraphic position of some can be ascertained. He distinguished three separate floras (Nathorst, 1920), of which the uppermost Diabasbukta flora, containing Cardiopteridium nanum, is from the Vegard Fm. However, this flora has not been identified elsewhere. The poor preservation of spores has frustrated palynological studies, and nothing is published on this formation. Hence correlation of the formation is tentative, but if the Orustdalen Fm, below, is of Late Visean to earliest Serpukhovian age (see below), then this formation is probably Serpukhovian. There are lithological similarities, (sandstones and shales with some red beds and thin coals), to the earliest Serpukhovian Hultberget Mbr of the Billefjorden Trough (see Chapter 4), with which it may be contemporaneous (Cutbill & Challinor, 1965). Orustdalen Formation. Sandstones and shales are the predominant constituents of this formation, which varies in thickness up to several h u n d r e d metres. The sandstones are invariably quartz rich but also contain clasts o f m e t a m o r p h i c rock and chert. Plant remains are c o m m o n but coal has only been recorded f r o m a single horizon on Broggerhalvoya where it is k n o w n only west of the K v a d e h u k e n Fault. There are no m a r i n e fossils but the flora indicates a Late Visean or Early S e r p u k h o v i a n age. The f o r m a t i o n represents a fluvial e n v i r o n m e n t on a growing alluvial fan building out from a fault scarp into a m a r i n e basin. Definition. Dineley (1958) divided the 'Culm' in Oscar II Land into two formations. His lower Trygghamna Fm is the equivalent of the Orustdalen Fm of Cutbill & Challinor (1965) which can be traced from Reinodden to Broggerhalvoya. It is 759 m thick in the type section at Orustdalen, thinning to 654 m north of Bellsund and only about 200~50 m at St Jonsfjorden. The upper boundary is conformable with the overlying Vegard Fm. The junction is marked by a change to a thick sandstone sequence with a sudden reduction in shales. The base is marked by an angular unconformity above pre-Devonian schists. Locally there are basal conglomerates. Lithologies. They are generally more arenaceous than the Vegard Fm. Monotonous light grey or white, thickly-massively bedded sandstones are

interbedded with thin, black, red or grey shale horizons (up to 20 cm locally). Sandstones are mainly medium-coarse grained and quartzitic, with common cross-bedding and ripple-marks. Lenses and beds of coarse quartz-conglomerate occur, especially within the bottom 50 m and there is a locally developed basal conglomerate (Orvin 1940; Hjelle 1962) that is rich in hematite in places. The conglomerates contain sub-rounded pebbles, not only of white veinquartz, but also of red and black chert and jasper, feldspars, schist and plant fragments up to 5 cm in diameter. They are associated with interbedded sandstones and shales. Thicker (20-40 cm) shales appear downwards, which are usually dark, but are locally grey or red. Plant remains are very common, though they are generally poorly preserved as carbonaceous impressions. There are no coals, except near the base on Braggerhalvoya, where a 3 m thick unit of poor quality coal (ash content 30%), and carbonaceous shale occurs (Orvin 1934). Fairchild (1982) mentioned a 7 cm in-situ coal seam with a 1 cm underclay in the same area and also another rootlet horizon 100 m further up. Palaeontology and age. Nathorst (1914) listed the flora of the Billefjorden Group, including many species which, by inference, came from the Orustdalen Formation. In addition, he distinguished three distinct floras, the lower two of which must be from the Orustdalen Formation (Nathorst 1920). The Hagerup Haus flora is the younger and contains Sphenopteridium norbergii and Thysanotesta sagittula. It is separated from the Camp Millar flora below by beds containing only Stigmariaficoides. The Camp Millar flora is characterized by Adiantites bellidulus, Lagenospermum arberi and Lepidodendron mirabile. However, these assemblages, which are almost certainly pre-Serpukhovian, have not been identified elsewhere. Forbes, Harland & Hughes (1958) noted the similarity of the Hagerup Haus flora to that found east of Festningen and at Billefjorden in the Svenbreen (or possibly the Horbyebreen) Formation which suggested a possible correlation, confirmed in 1982 by Fairchild (see below). Lepidodendron Nordenskidldii, L. heerii, Sphenopteridium norbergii, Adiantites bellidulus and Cardiopteridium ?spetsbergens, found at Billefjorden in the Svenbreen/ Horbyebreen formations, are also recorded by Nathorst from the Orustdalen Formation and Lepidodendron rhodeanum, Lepidodendron robertii and Sphenopteris bifida are common to both the Svenbreen and Orustdalen formations (Cutbill & Challinor 1965). Earlier attempts to describe the palynology of these strata were frustrated by the very poor preservation of microfossils in this western region, probably a result of the Tertiary orogeny. However, one horizon low in the sequence on Broggerhalvoya has yielded spores which indicate a Visean/earliest Namurian age (Fairchild 1982). Lycospora pusilla and small Densosporites are common. Thus the Orustdalen Formation is probably of Late Visean or possibly Early Serpukhovian age and correlates with the Mumien Formation, a correlation supported by its lithology which resembles that of the lowermost member of the Mumien Formation.

9.4

Early Paleozoic rocks

Early publications on this area were few and include H o l t e d a h l ' s (1913) observations and Orvin's (1934) detailed study o f Broggerhalvoya as part o f a t h o r o u g h description of the N y - A l e s u n d coalfield. Post-war research increased greatly beginning with B i r m i n g h a m University expeditions in 1948, 1957 and 1958 (Baker, Forbes & H o l l a n d 1952; Weiss 1953, 1958; Dineley 1958). Structural studies by B a r b a r o u x (1966a, b) and Challinor (1967) followed. The blueschists of Motalafjella were intensively studied after their discovery by C a m b r i d g e parties in 1961 (Horsfield 1972; O h t a 1979, 1985a, 1992; Ohta, Hiroi & Hirajima 1983; Ohta, H i r a j i m a & Hiroi 1986; K a n a t 1984a, b). Ordovician-Silurian fossils were reported by Scrutton, Horsfield & H a r l a n d (1976) a n d by A r m s t r o n g , N a k r e m & O h t a (1986). The rocks, largley Ordovician are described in two distinct units: the Bullbreen G r o u p and the Vestg6tabreen Complex.

9.4.1

Bullbreen Group (Harland, Horsfield et al. 1979)

Different stratigraphic schemes have been proposed for the rocks, n o w k n o w n to be of Early Paleozoic age a n d occurring mainly as outliers in the area south of St J o n s f j o r d e n (Motalafjella t h r o u g h Holmesletfjella across Bullbreen to Bulltinden) and n o r t h of the

CENTRAL WESTERN SPITSBERGEN fjord at Ankerfjella, Kaffioyra a n d Sarsoyra. T h e successive cont r i b u t i o n s are r e c o u n t e d a n d a unified n o m e n c l a t u r e is p r o p o s e d . Holtedahl (1913, p. 57) reconnoited the southeast shores of St Johnsfjorden and noted a conglomerate with boulders matching, for example, his Alkhorn limestones. This was most probably at Bulltinden, west of Bullbreen. In 1959 from a temporary anchorage at Copper Camp, Harland noted the extensive flysch sequence of calcareous argillites and polymict conglomerates referring them to his Holmesletfjella unit (1960), although mistakenly placed earlier than the Comfortlessbreen Group. Wilson & Harland (1964), Winsnes (1965) and Flood, Nagy & Winsnes, 1G, (1971) related the conglomerate to the Comfortlessbreen tilloids but the stone content did not match. In 1968 Horsfield & Harland suspected fossils from limestone clasts and in 1969 Horsfield collected fossils from the conglomerates in Motalafjella. The fauna was tentativelly identified with late Ordovician or early Silurian forms. In 1971, Harland revisited the locality and made a small collection from a penecontemporaneously slumped limestone within the conglomerate. The two collections together suggested a Wenlock or Ludlow age (Scrutton, Horsfield & Harland 1976) where the scheme in Harland et al. (1979) was used because it had been submitted in 1975. Horsfield (1972) in describing the Vestg6tabreen Complex metamorphism described all the later rocks as the Bulltinden Fm (Harland, Horsfield et al. 1979). As part of a stratigraphic scheme for the whole of Oscar II Land, they made the Bulltinden conglomerate a member within the Homesletfjella Fm, and placed the underlying strata-mainly limestones in another formation the Motalafjella Fm. Ohta (1979) followed Horsfield (1972) his paper being in the same publication as Harland et al. (1979). Ohta, Hiroi & Hirajima (1983) identified the contact between the metamorphic complex and showed it to be an overturned unconformity which they mapped. They used the name Bulltinden Formation for the conglomerate and the older basal limestone above the complex, supposedly following Harland et al. (1979) for this usage. Armstrong, Nakrem & Ohta (1986) reported significant conodont studies which suggested a Caradoc or earlier age for the basal limestone and also for a limestone lens within the overlying sandstone and shale member. The overlying boulder conglomerate with slumped olistostromes were suggested to be of Early Silurian age. These three members were of the Bulltinden Fm. Kanat & Morris (1988) in describing this general succession in the St Jonsfjorden area followed Harland, Horsfield, Manby & Morris (1979) referring to the two formations Holmsletfjella (above) and Motalafjella (below) and comprising the Bullbreen Group. They described the sequence in detail for the first time. Their scheme is followed here except for the Bulltinden conglomerate member. It has proved to be the most conspicuous unit, occasionally of great thickness, has been frequently referred to in the literature, was first noted with fossils, later yielding a distinct fauna. Therefore it was upgraded to formation rank and the two members beneath it were transferred into the Motalafjella Fro. The proposal is thus, details follow.

BuUbreen Gp Holmesletflya Fm (probably Silurian) Bulltinden (conglomerate) Fm (Early Silurian) Motalafjella Fm (Late Ordovician)

HolmesletfjeUa (slate) Formation, first identified as W6, by W i l s o n in 1958, the e p o n y m o u s m o u n t a i n was revisited a n d n a m e d ( H a r l a n d 1960) b u t in m i s t a k e n order, s o m e w h a t rectified by H a r l a n d e t al. (1979). T h r e e m e m b e r s were described ( K a n a t & M o r r i s 1988). Siliceous slate mbr, 20m (BH6 of Kanat & Morris) is best exposed in northern Holmesletfjella, is a friable siliceous slate, upper contact not known. Elongate irregular dark features were interpreted as trace fossils. Lower boundary is sharp and conformable . Sandstone slate mbr, 100m+ (BH5 of Kanat & Morris) exposed in Holmesletfjella and Motalafjella, Bulltinden, Ankerfjella etc. interbedded calcareous sandstones (65%), slates (25%) and immature and impersistent conglomerate horizons (10%) show cross bedding, conspicuous from a distance due to colour-banding (grey to buff) and reveals fiat-lying nearisoclinal folds giving a first impression of much greater thickness. The base is transitional with decrease in conglomerate content. Slate Mbr, 30 m (BH4 of Kanat & Morris) is black, slightly calcareous and of similar extent to the above member. Its base is sharp. Bulltinden (conglomerate) Formation, 10 60 m (BH3 o f K a n a t & M o r r i s ) is m a i n l y a p o l y m i c t c o n g l o m e r a t e with clasts r a n g i n g in

163

size f r o m granules u p w a r d s t h r o u g h b o u l d e r s to s l u m p e d olistost r o m e s , a n d is variably i n t e r - b e d d e d with s a n d s t o n e s a n d slates similar to the Holmesletfjella F o r m a t i o n . It has been described in detail by K a n a t & M o r r i s (1988) with clasts o f l i m e s t o n e 4 0 % , schist 2 5 % , s a n d s t o n e 2 0 % , d o l o s t o n e 10% c o n g l o m e r a t e 5 % , dolerite < 1 % . T h e clast lithologies m a t c h either those o f the Bullbreen G r o u p or the m e t a m o r p h i c s o f the V e s t g 6 t a b r e e n C o m p l e x ; s o m e o f the l i m e s t o n e s m i g h t be V e n d i a n . Fossils were first noted in the limestone clasts and a distinct coral, gastropod, bryozoan, echinoid fauna was collected from a 100+m 3 olistostrome (Scrutton, Horsfield & Harland 1976) estimated to be of late Llandovery to Wenlock age. Work on conodonts confirmed an Early Silurian age (Armstrong, Nakrem & Ohta 1986). Harland's opinion was that this slumped mass, unlike some conglomerate clasts was penecontemporaneous. The base of the formation is a sharp erosive sedimentary contact.

Motalafjella (slate and limestone) Formation, 2 6 0 m ( H a r l a n d , Horsfield e t al. 1979). This f o r m a t i o n newly includes the two lower m e m b e r s f r o m the Holmesletfjella F o r m a t i o n o f K a n a t & M o r r i s w h i c h is d i v i d e d here into t w o units, the lower o f w h i c h was classified by t h e m with the V e s t g 6 t a b r e e n C o m p l e x . T h e r e are t h u s five m e m b e r s . Slate Mbr, 10 m (BH2) a black ferruginous slate (with bands of subhedral pyrite. The base is transitional. Sandstone-slate Mbr, 150m (BH1 of Kanat & Morris) best seen in western Motalafjella, but also Holmesletfjella, Ankerfjella and in Bulltinden, where the upper contact is under the Bulltinden conglomerate. Within the sandstones up to 10% of conglomerates may occur and both sandstone and conglomerate may give way to slate. The carbonate content here is greater than in the Holmesletfjella sandstones. The lower contact is sharp but conformable. Limestone Mbr 100 m (BM1 of Kanat & Morris). This is predominantly of limestone which forms the peak of Motalafjella and is only 3 m at Ankerfjella. a gritty (up to 30% detritus) fossiliferous (crinoid stems and coral fragments) cryptocrystalline grey, buff-weathering, limestone. This limestone seems to be the source of the fossiliferous clasts in the Bulltinden conglomerate. It was also the source of the Caradoc or even Arenig conodonts described by Armstrong, Nakrem & Ohta (1986). The (somewhat tentative) conclusion of their study combined with the macrofossil evidence is for a Caradoc age. Conglomerate slate Mbr (BM1 of Kanat & Morris). A thin member or bed at the base of the limestone is indicative of a basal conglomerate. Dolostone Mbr, 0 - 2 0 m (VOD of Kanat & Morris). This distinctive orange-weathering dolostone is consistently found below the Motalafjella unit (BM1) where it is in contact with the Vestg6tabreen Complex, except at Ankerfjella and Bulltinden where it is in contact with the Comfortlessbreen Group. Ohta, Hiroi & Hirajima (1983) demonstrated a basal unconformity contact with the complex and limestone and metamorphic fragments in the succeeding dolostone. The rock is a coarsely crystalline grey siliceous dolostone with 5% or even 10% of chromium phengite (mariposite) weathering to a distinctive orange. It has the fabric of a thrust breccia in places. The high magnesium, chromium and nickel content suggest a carbonated metasomatized ultrabasic rock, associated with the Vestg6tabreen Complex. The conclusion here is that, from its consistent occurrence at the base of the Motalafjella Formation and from the description of Ohta et al. it belongs to that formation but it has been selected as a thrust horizon. This would reconcile the apparently conflicting observations; but it leaves unresolved the contact at Ankerfjella, which while clearly a thrust contact may yet have been unconformable there also. Some mineralization may well have been selected by the thrust surface. Ferruginous waters pour down from a spring in the scree on northern Motalafjella at about this horizon, east of Copper Camp. The mineralization could well be Paleogene (see Chapter 20). Sarsoyra Formation, 450 m. This f o r m a t i o n is seen in c o n t i n u o u s white cliffs w h i c h b o u n d the S a r s o y r a plain to the east. W i t h i n the S a r s o y r a plain leading o u t to the n a r r o w a n d shallow passage at S a r s t a n g e n are scattered o u t c r o p s with a N - S o r i e n t a t i o n investigated by C S E as follows. C. B. W i l s o n suggested a h o r s t structure, W . T . Horsfield n o t e d s l u m p e d blocks o f the n e i g h b o u r ing T e r t i a r y facies related to it a n d t h a t all were a l l o c h t h o n o u s . H a r l a n d first suggested a step-faulted s t r u c t u r e at the m a r g i n o f the graben, w i t h fault scarps f r o m w h i c h blocks slipped a w a y in a

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CHAPTER 9

rapidly accumulating sedimentary sequence. On this basis some of the larger outcrops would be in s i t u horsts. From further investigation in 1992 he found it difficult to fit the various exposures into a systematic pattern of outcrop or strike. The original idea of strips of rock units could be ruled out, nor did it seem likely that the larger masses could have slipped off fault scarps. They were too large and internally coherent. Nearly every exposure was associated with tectonic breccias. It therefore seemed most likely that the area contains disoriented slices in a large-scale melange strike-slip zone. The lithologies include unsorted clast-supported conglomerates and breccias with pebbles up to 15 cm of white quartzite and vein quartz, finely bedded sandstone to siltstone and psammitic schists. There were also units of dolomitic marble (some of reddish tint) these were generally brecciated. The quartzite and dolostone facies were closely associated. The age of these rocks has been debated as between Carboniferous or Silurian. The earlier age was suggested from a pebble (in a conglomerate in the formation) which contained a lykophyllid coral. The conglomerate was first taken as part o( the Bullbreen Group (see below) by Scrutton et al. (1976). However, C. L. Forbes suggested that a Late Paleozoic age was just as likely. In any case the formation does not have to be the age of its constituent pebbles. Therefore a Carboniferous or possibly Permian age was then preferred. However the new age determination by Makanjev (pers. comm. in Ohta et al. 1995) supports the original opinion of Scrutton et al. (1976).

Aavatsmarkbreen Formation, 600 m. This formation comprises a thick succession of dark grey phyllite, volcanites, psammites and subordinate carbonate. It is isoclinally folded and thickness is difficult to estimate. The lower boundary is not exposed but a transition by alternation with facies of the underlying formation is likely. Three informal divisions have been suggested (Harland, Hambrey & Waddams 1993): (3) c. 300-400 m of highly deformed grey and black phyllite, with thin black marble, white marble, sandy dolostone and quartzite interbeds; (2) 6 - 1 0 0 m of dark green black slate with some quartzite beds At Snippen (south of the Annabreen Formation section) there are soft light green and purple banded shales. (1) c. 400m of dark phyllite and black limestone with thin conglomerate and pink psammite interbeds. Whereas Harland et al. (1993) took this to be the top formation of the Comfortlessbreen Group and of probable Ediacara age, Ohta et al. (1995) with further evidence identified the sequence as belonging to the Bullbreen Group and so of Ordovician to Silurian age. This revision is followed here. 9.4.2

Vestg6tabreen Complex

On Cambridge expeditions in 1958 C. B. Wilson noted high-grade metamorphic rocks in the Eidembreen moraine, D. G. Gee in 1962 located their source showing the presence of glaucophane schists at Motalafjella. Horsfield worked in the area from 1968 (1972) when he showed isotopically that the metamorphism was Paleozoic, probably Ordovician (i.e.c. 470 Ma) and he suggested a subduction zone. These finds led to further mineralogical work e.g. Ohta (1979), Kanat (1984a, b), Ohta, Hirojima & Hiroi (1986) and Kanat & Morris (1988). Age of the Complex. Motalafjella is also noteworthy for its Ordovician and Silurian fossils (see 9.6.1 and 14.4.4) which show the complex to have been metamorphosed not later than Caradoc time and further deformed and thrust in late or post-Silurian time and part at least in Paleogene time. Subduction models have been proposed which if valid would have to reflect an early to midOrdovician Eidembreen event. The age of the protoliths is unknown. The basic igneous composition might match that of the Early Varanger volcanics The limited exposure in only three mountain inliers gives no regional handle to speculate further. These would be from the Lovliebreen Formation suggested by Harland, Hambrey & Waddams (1993) and by Ohta e t al. (1995) which authors differ as to to its age.

Structure of the Complex.

The Vestg6tabreen Complex is closely associated with the Bullbreen Group and crops out in four mountains: Motalafjella, two spurs of Holmesletfjella, north and south of upper Hydrografbreen (formerly Skipperbreen), and Bulltinden. A further outcrop, a distinct klippe of Bullbreen strata occupies the top of Ankerfjella north of St Johnsfjorden. All these outcrops appear to be part of a single folded thrust unit in which the rocks are overturned, so that the OrdovicianSilurian Bullbreen rocks dip beneath the complex in the limbs of a west-dipping overturned syncline seen well in the Bulltinden conglomerates. The Vestg6tabreen-Bullbreen unit has been thrust up and over Vendian rocks from the west or southwest. The contact between the Bullbreen Group and the Varanger groups is not well exposed, but is probably everywhere a thrust surface. It is perhaps best seen north of St Jonsfjorden at Ankerfjella where it is almost horizontal. The nature of the contact between the Complex and the younger Bullbreen Group is critical. Ohta, Hiroi & Hirojima (1983) argued for an unconformity (overturned) on the basis of evidence at seven localities where the Motalafjella limestone contains fragments of an older dolostone which it also penetrates. In addition there are clasts of the metamorphic complex. This conglomeratic zone extended 3 to 5 m from its structural upper surface. The limestone contains gastropods. Moreover, fossil bearing limestone pebbles occur still further from the contact. At one locality the conglomerate layers are cross-bedded and confirm that the strata are inverted. K a n a t & Morris (1988) who surveyed the area, including Ankerfjella, were puzzled by the ochre weathering dolostone (their unit VOD) that occurs nearly everywhere at or near the contact of the complex and the Bullbreen Group, and also at Ankerfjella. They placed it within the Vestg6tabreen Complex and to be subject to thrusting. It is thought here more likely to belong to the basal facies of the Motalafjella Formation of the Bullbreen Group, but agreed that some thrusting has taken place along the unconformity surface. There would thus have been a complex history of successive erosion and deposition phases first of metamorphics, then of dolostone, then of limestone followed or accompanied by folding and thrusting in places along this zone. Lenses of the dolostone are found near the contact with the schists and there are some mylonitic textures. The dolostone itself is often rich in metamorphic clasts similar to those of the complex. On Motalafjella the complex is divided into at least two units by a thrust as depicted by Ohta, Hirajima & Hiroi (1986). Moreover, that the whole complex has been subject to penetrative shearing is evident from the ubiquitous schistosity. The thrusting appears to be a part of the (Eocene) West Spitsbergen Orogeny. Five lines of evidence support this conclusion. (i) The whole of the orogen of which this unit is a part, exhibits eastwards or northeastwards verging overfolding and thrusting, including Paleozoic and Mesozoic rocks. (ii) To the west, as at Farmhamna, fossiliferous Carboniferous strata are seen vertically adjacent to Vestg6tabreen-Bullbreen Varanger strata. (iii) The schistose complex dips beneath glaciers, to the west of which rise Carboniferous mountains. This relationship is easiest to explain by postulating a further arcuate thrust occupying the ice-covered area rather than by an arcuate normal dip-slip fault. (iv) The Vestg6tabreen-Bullbreen thrust mass swings round from eastwards verging in Motalafjella to northwards verging in Bulltinden which is consistent with a dextral transpression. (v) In 1968 Harland showed Horsfield, on the south flank of the spur of Motalafjella north of Skipperbreen, a lens of fossiliferous limestone of Carboniferous facies in an apparent thrust surface. It is not impossible that it could have been Silurian. That possibility was not then in mind. A post-Bullbreen Group pre-Carboniferous tectonic episode might also have taken place.

Succession of the Complex. In view of the complexity of the metamorphic rocks, which all show evidence of shearing, any succession may not relate to an original stratal or thrust sequence. Nevertheless, Kanat & Morris mapped the following sequence, listed here from the (?) thrusted unconformity:

CENTRAL WESTERN SPITSBERGEN their orange weathering dolostone medium grey micaceous marble dark grey micaceous marble mafic schist serpentinite pelite schist greenstone psammite garnet glaucophanite eclogite

(VOD) VM2 VM1 VSH VSP VPE VGT VP3 VGG VEC

up to 20 m 50+ m 50+ m c. 200 m 15 m 10 m 50 m 4m 50+ m 40+ m

Ohta, Hirajima & Hiroi (1986) described two units separated by a west-dipping thrust. The lower unit (structurally is mainly of sericite chlorite phyllites with scattered lenses of dolostone, quartzite, metabasite and serpentinite. The upper unit is of garnet mica schists, schistose limestone and lenses of garnet glaucophanite and eclogite.

Mineralogy and chemistry of the complex.

The blue-schist facies has attracted much research. Horsfield (1972) described glaucophane schists (but did not find lawsonite, aragonite or pumpellyite) in the course of his chemical analysis and isotopic dating of them. Ohta (1979) reported both the bulk chemical composition and that of individual mineral species analysed by a number of workers. Typical mineral assemblages were:

glaucophane schists: garnet-glaucophane schist with muscovite and chlorite; garnet-muscovite-glaucophane schist; garnet-epidote-muscovite-glaucophane schist; eclogitic rocks: schistose glaucophane-garnet-omphacite (up to 90%) eclogite; epidote amphibolites: actinolite-epidote sericite-chlorite-plagioclasequartz schists; epidote calcite-chlorite-actinolite-plagioclase-greenstone; garnet-bearing epidote amphibolites: garnet-epidote-actinolite-chlorite meta-diabase; garnet-epidote-sericite-actinolite schist; garnet-actinoliteepidote-chlorite-sericite-plagioclase schist; garnet-chlorite-sericite-plagioclase-quartz-metagabbro; glaucophane-muscovite-quartz schists: variably with garnet or hematite. Ohta (1979) compared the above with other west-coast basic rocks. But in referring them to Late Riphean he was not aware of the evidence that the basites are intertillite and if so of Varanger age. He concluded for the origin of the Vestg6tabreen complex as follows. 1. Most epidote amphibolites were derived from intermediate differentiates of basaltic magma. 2. Some relatively acidic varieties are not later differentiates of basaltic magma, but mixtures of intermediate differentiates and argillo-siliceous sediments. 3. The muscovite-quartz schists with or without glaucophane were formed from impure argillaceous quartzite. 4. The glaucophane schists are mixtures of early differentiates of the basaltic magma and argillo-siliceous sediments. 5. Na enrichment is not prominent in the glaucophane schists and the original rocks were not typically spilitic. 6. The original volcanic rocks of these basic rocks are unknown, and they have large variation presumably by tectonic stirring. Kanat (1984) described jadeite from the upper member and estimated pressures between 9.9 + 0 . 5 k b as at 300~ and 12.8kb as at 450~ Horsfield's first estimate from the garnet-biotitehornblende assemblages suggested 300~ at peak metamorphism with a palaeogeothermal gradient of 30~ km -1. Ohta, Hirajima & Hiroi (1986) reported i.a. lawsonite and jadeite-quartz-albite assemblages.

9.5

Proterozoic strata of Oscar II Land

The overall stratigraphy of the area was first reconnoitred by C. B. Wilson in 1958 (Harland 1960) and with further work was synthesised by Harland, Horsfield, Manby & Morris (1979), and by Hjelle, Ohta & Winsnes (1979) and by Kanat & Morris (1988) and then by Harland, Hambrey & Waddams (1993). The rocks are described in three groups: Comfortlessbreen; St

Jonsfjorden and Kongsvegen.

9.5.1

165

Comfortlessbreen Group

The group is now defined by the Annabreen and Haaken formations. A meta-tillite was first suspected and the rocks so named (Harland 1960) since when a complex series of reinterpretations of the stratigraphy end with the scheme presented here (Harland, Hambrey & Waddams 1993). In that work, Aavatsmarkbreen was described in detail with four sections plotted from Sarsoyra and Kaffioyra. They regarded it as the highest formation in the Comfortlessbreen Group and possibly Late Vendian (Ediacara) age to correspond to the Scotia Group in Prins Karls Forland. However, from Ohta et al. (1995) the evidence suggests that the formation belongs to the Bullbreen Group where it is treated under Section 9.4.1.

Annabreen Formation (thickness variable, about 2 km). Wilson referred to Annabreen Quartzites and although the eponymous locality Anna Sofiebreen is south of St Jonsfjorden. The best sequence is seen around Aavartsmarkbreen. Cutbill & Challinor (1965) renamed them Irenebreen Quartzites as [?] Carboniferous whereas Hjelle, Ohta & Winsnes (1979) incorporated them in the Bullbreen Group. Harland, Hambrey & Waddams (1993) made it a constituent formation of the Comfortlessbreen Group. The formation comprises quartzites and shows gradational transitions above and below with thin phyllite interbeds above and dispersed dolostone and quartzite pebbles, up to 30 m at Dahltoppen, towards the base. Haaken Formation, 2-3 km (Harland, Hambrey & Waddams 1993). The name Haaken schists was used informally by C.B. Wilson (his horizon 7 in Harland 1960) and is best seen at Engelskbukta. Hjelle et al. 1979 referred to the same unit as tillitic conglomerate. The outcrop width of 6 km of steeply dipping strata was estimated by Waddams (1983) to have been duplicated by folding and thinning to about twice the original thickness. An eastern belt of the same formation is accessible from the head of St Jonsfjorden. The formation consists of stone-bearing orange to grey weathering psammitic schist - or schistose diamictite, interbedded with blue and grey weathering quartz-rich schist and laminated quartzite, the schistose foliation follows approximately the original bedding. The stones, comprising about 10% of the rocks, consist of dolostone, limestone, quartzite and both foliated and unfoliated granitoids up to lm long (the largest seen 2 • 1 • 0.7 m). Whereas the Annabreen facies is of proximal turbidite facies the Haakon facies is of distal turbidite facies, both with ice-rafted stones.

9.5.2

St Jonsfjorden Group

Defined by Harland et al. (1979) as comprising the four following formations, Harland, Hambrey & Waddams (1993) argued that the whole Group is Vendian (early Varanger). Hjelle et al. 1979 made them pre-Vendian, referring to them as Middle Hecla Hoek, and Ohta et al. (1995) implied a Mesoproterozoic age.

Alkhorn Formation 1+ km. The name is from 'Alkhornkalk' of Holtedahl (1913) conspicuous at Alkhornet on the southern cliffs of Oscar II Land where the lower part of the formation is exposed. Independently in north Oscar II Land, Harland (1960) recognized Holtedahl's Alkhornkalk, whereas Wilson used the name Dahlbreen limestone which Harland et al. (1979) regarded as the same unit and so adopted the earlier name. It was also referred to by Hjelle et al. 1979 as the Calc-argillo-volcanic Formation, metavolcanic and intrusive rocks having been recognized mainly in the upper part. A complex succession of facies (Harland, Hambrey & Waddams 1993) may be summarized as an alternating sequence of marble or grey limestone (often oolitic) and a variety of metabasites. Ohta (1984) referred to the igneous assemblage (the rich tholeites) as of oceanic type. Lovliebreen Formation, 1 km. The Formation is named for a glacier south of St Jonsfjorden (Harland et al. 1979). This unit corresponds to the dark quartzites of Holtedahl (1913), the massive quartzite bodies of Weiss (1953) and broadly equivalent to the Quartzite Shale Formation of Hjelle et al. (1979). A modified map (Ohta 1984) plots a broad belt from Loveliebreen to Isfjorden whereas north of St Jonsfjorden there is only a small outcrop. Two members have been distinguished (Harland et al. 1979).

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(2) Upper: massive dark quartzites with intercalated pelites the quartzites, are cut by thin white quartz veins - they are well- sorted fine-grained metasandstones. (1) Lower: foliated dark brown, green and purple volcanic rocks, with amygdaloidal basalts and pyroclastics. Some are reddened suggesting subaerial weathering. Unlike the Alkhorn Fm the igneous facies suggest sodaalkaline lava flows with some pillow structures. Geochemically they are of a non-oceanic type (Ohta 1984). Kanat & Morris (1988) made the Loveliebreen younger and than the Alkhorn units. Harland, Hambrey and Waddams (1993) disagreed believing i.a. that intrusive dolerites and the Loveliebreen volcanics had been confused. The latter may not have seen by Kanat & Morris.

Moefjellet Formation, 500-800m. C. B. Wilson named this massive, uni-form, unfoliated, cream-weathering bluish grey dolostone with a gritty or sandy texture and some cherty layers. Shallow water deposition with algae mats has been suggested. Daudmannsodden Formation (Ohta 1985) of highly sheared dolomitic marble could be a tectonised equivalent of the Moefjellet Formation (Harland, Hambrey & Waddams 1993). Trondheimfjella Formation (1.3 km). This schistose calc-diamictite was so named by Wilson as a conglomerate. His map was available to the Norsk Polarinstitutt who (Hjelle, Ohta & Winsnes 1979) remapped it as part of their Tillitic Conglomerate Formation and near the top of their sequence. Harland e t al. (1979) in the succession followed here, placed it at the bottom of their succession as did Wilson. Waddams (1983) found a tillite facies north of Engelskbukta and identified it with the earlier Varanger tillite (i.a. lacking granitoid stones). This was accepted by Harland, Hambrey & Waddams (1993) as evidence that the overlying formations of the St Jonsfjorden Group lie between the upper and lower tillite horizons and so must all be of Varanger age. Perhaps this realisation encouraged the solution to problem of correlation along the west coast, where, as in Oscar II Land, thick successions, with a basic igneous component, were all formed between or within the two Varanger glacial episodes and so restrict much of the west coast Proterozoic sequence to Vendian age. The meta-diamictites are distinguishable from those of the Haaken Formation by a matrix-rich carbonate rather than a phyllite and by the lack of exotic clasts such as granites and gneisses, the stone content being typically intrabasinal. These characters suggest an origin by ice rafting into a distal turbidite basin. A band of stromatolites near F a r m h a m n a indicates shallow marine carbonate shelf, or proximal environment. Harland e t al. (1979) proposed three members. (3) Marble flags (500 m). (2) Dark phyllitic semi-pelites and psammites with minor quartzites and calcareous beds (300 m). (1) Thin orange-weathering bands of calcareous in conglomerates a sequence of quartzites, psammites and massive dolostones (300 m). The upper contact is transitional and the lower contact faulted. There is no basal conglomerate with clasts matching the underlying formations.

9.5.3

Kongsvegen Group

In his survey of Broggerhalvoya Orvin (1934) set up 11 units of metamorphic rocks as follows, unit 1 at the top: 1-9 10 11

'Quartzite and mica schist series' (2520 m) Steenfjellet Dolomite (270 m) Bogegg Mica Schist (1500 m). The matter proved complex as follows.

Orvin (1934) identified a further unit, 'dolomites and limestones', beneath with his units 1-11 (see below) and Challinor (1967) referred to this as the Bjorvikfjellet Formation. Harland et al. (1979) identified this with the overlying Trondheimfjella Formation (confirmed by Harland, Hambrey & Waddams 1993).

Correlating northwards across Kongsfjorden, Orvin made the Blomstrandhalvoya marble (Genaralfjella Formation) his topmost unit of the Hecla Hock succession above unit 1; the schists of Signehamna Formation (equivalent to his units 1-9), and the Nissenfjella Formation with its feldspathic rocks (migmatites) as the granite of the pre-Hecla Hock basement. Little was then known of other pre-Devonian successions and proceeding with this sequence as seen from the north his scheme was coherent. Wilson's reconnaissance of the rocks of Oscar II Land south of Broggerhalvoya in 1958 led to his reversing the succession with his Trondheimfjella rocks above the Bogegg schists, as reported and followed by Harland (1960). However, when revising the Hecla Hock succession in Ny Friesland, Harland et al. (1966) referred to the Kongsvegen Gp comprising Orvin's three formations and (knowing Challinor's t967 conclusions) followed Orvin's order of succession. Challinor (1967), while not accepting Orvin's correlation north of Kongsfjorden, named Orvin's units 1-9 the Nielsenfjellet Fm (at the top) and Orvin's 'dolomites and limestones of Forlandsundet' as the Bjorvigfjellet Fm at the bottom of the Kongsvegen Gp (Harland et al. 1966) underlying the 'Bogegga Fm' so again following Orvin's order of superposition. However after a reconnaissance survey of the whole of Oscar II Land Harland et al. (1979) concluded that Wilson had been correct in that the Kongsvegen Gp was the oldest in that area (and probably younger than the rocks further north). Nevertheless, it was assumed that the metamorphic grade of the Kongsvegen Gp made it significantly older than that of St Jonsfjorden G p - that, indeed, it was a potential basement to the St Jonsfjorden Gp. They retained Orvin's sequence, adding detail of the Bogegg Fm. Further study of Oscar II Land (Harland, Hambrey & Waddams 1993) led to the view that the Mfillerneset Fm (south of St Johnsfjorden) which was correlated with, and included in, the Kongsvegen Gp might have been conformable (at least concordant) with the Trondheimfjella Fro. In 1992 CSE concluded that, as seen north of Engelskbukta, the Boggegg, Trondheimfjella, and the Moefjellet fms lay in a normal sedimentary sequence with interbedding and transitional facies at the boundaries. No evidence for any major discontinuity (unconformity, thrust or both) was evident locally. Inadavertently they tabulated Orvin's order of the Kongsvegen Gp which they had not investigated. The conclusion here is quite clear in spite of the above confusion. Wilson was correct: the Trondheimfjella Formation at the base of the St Jonsfjorden Group rests concordantly on the Bogegga Formation at the top of the Kongsvegen Gp. In the light of the above complex sequence of opinions the conclusion is summarised below. The apparent differences in metamorphic grade are probably accounted for partly by composition of the protolith and partly by depth in the succession.

Kongsvegen Group North of St Jonsfjorden Bogegg Formation, 1500m, is a varied sequence, dominantly pelitic Member (3), 500 m. Half the bulk is of pelites and semi-pelites of biotite and garnet schists containing quartzo-feldspathic bands and lenses. These are intercalated with orange-weathering marbles and psammites. The other half is of coarse grained marbles Member (2) 500m. Dark feldspathic and garnetiferous semipelite with quartz feldspathic bands and segregations. Member (1) 500m. Gneissic porphyroblastic (augen) feldspathites and semipelites and schistose garnetiferous pelites dominate with bands of dolostone and impersistent concordant amphibolites. Steenfjellet Formation, 270 m a convenient prominent marker formation of grey to cream coloured dolomitic marbles separates the formations above and below. Nielsenfjellet Formation (2+km) (Challinor 1967, Orvin's Quartz Mica Schist Series) of monotonous dark phyllitic semi-pelites interspersed with paler, dolomitic quartzite bands. Orvin's description of these rocks (unit 1-9) applies to the cliffs north of Austre Broggerbreen. The mountains further east - towards Nielsenfjellet yield a variety of schists and gneisses with an igneous component and whose relationships have yet to be determined. South of St Jonsfjorden Miillerneset Formation. Occupying the west coast between St Johnsfjorden (Mfillerneset) and Eidembukta, the Formation consists of phyllitic and schistose pelites interbedded with semipelites and white quartzites (Harland et al. 1979; Hjelle, Ohta & Winsnes 1979; Ague & Morris 1985; Kanat & Morris 1988).

CENTRAL WESTERN SPITSBERGEN North of Eidembukta the strata appear concordant and transitional beneath the Trondheimfjella Formation. The metamorphic contrast which has led to the view of a much older unit may stem from the tectonic juxtaposition of M~illerneset and Comfortlessbreen rocks where the whole intervening St Johnsfjorden Group (>4 km) is not seen.

Oscar II Land an Ordovician to Silurian age. That no fossils have yet been recorded may be the consequence of such a mobile environment. How much and what parts of Early Paleozoic time is represented can only be guessed.

9.6.2 9.6

Pre-Carboniferous rocks of Prins Karls Forland

A p a r t from Q u a t e r n a r y cover no D e v o n i a n or y o u n g e r rocks have been identified on Prins Karls F o r l a n d and an apparently uninterr u p t e d sequence o f strata m a y contain a u n i q u e passage for Svalbard from V e n d i a n t h r o u g h early Paleozoic strata; but with little palaeontological evidence to confirm it (see Fig. 9.8). The island is easily accessible and m u s t have been visited m a n y times. H o w e v e r , the evident lack o f macrofossils m a y have t u r n e d geologists elsewhere until the systematic study by Tyrrell (1924) and later by A t k i n s o n (1956, 1960 and 1962). E x p l o r a t i o n h a d tended to be a British interest since t o p o g r a p h i c surveys u n d e r Bruce's leadership of the Prince of M o n a c o expeditions in 1907, 1908 and 1910, and the attentions of the Scottish Spitsbergen Syndicate (Tyrrell 1924). The rocks were described by M a n b y & Morris (in H a r l a n d et al. 1979) a n d by Hjelle, O h t a & Winsnes (1979). W h e r e a s the second of these gave valuable description of the rocks only the first p a p e r a r g u e d a stratigraphic sequence. H a r l a n d , H a m b r e y & W a d d a m s (1993) in their synthesis followed that sequence. The detailed occurrence and origin of the names is given in the 1979 paper, w h e r e possible names were taken from the previous w o r k o f Tyrrell a n d Atkinson.

9.6.1

Grampian Group (Early Paleozoic)

This g r o u p is typically siliciclastic and flyschoid, it is defined by the following five formations.

Geddesflya Formation >1800m. This upper-most unit occurs in the northern part of the island. It is mainly quartzitic with dolostone banded siltstones, breccias, thin siltstones and slates. Lower down are slate-pebble breccias with banded siltstones. Lower still are thinly bedded quartzites and banded siltstones. Fugelhuk Formation 400-1000 m. Massive bedded quartzites occur in the cliffs at the north of the island. Beds, commonly one metre thick, are interbedded with banded siltstones. They thicken northwards to 1000 m. Barents Formation, 500m. This formation is dominated by siltstones which locally become black to dark grey slates. Below this is a sequence of folded banded siltstones and below again flaggy calcareous sandstones and then green pelitic quartzites with black limestone and pebbly quartzite. The remarkable Sutorfjella Conglomerate is treated by us (as by Atkinson) as a member within this formation although others have regarded it as a younger independent unit such as Devonian (Hoel 1914; Craig 1916) or Tertiary (Tyrrell 1924). They were first reported by Hoel. Krasil'shchikov favoured a Tertiary age. But CSE observed near the shore to the south evidence of interbedding with the Barents slates. The conglomerate contains clasts of underlying formations- mainly brown weathering, pale grey quartzite. Some horizons are rich in green cleaved siltstone, similar to that of the matrix. Another clast type is black mudstone with quartz~lolomite veining. These rock types are sufficiently distinctive to give confidence in this order of superposition. The quartzite boulders show red oxidized skins suggestive of subaerial weathering. The whole assemblage could have formed on a fault scarp. The cleavage of the matrix and of many clasts parallels that of the Barents Formation as a whole. Conqueror Formation, 500-850 m. Transitional with the Barents Formation at the top of the Conqueror Formation is a distinctive sequence of quartzites and slates. Below this are dark grey slates alternating with quartzite. Pebbly calcareous beds then overlie thick slate with more quartzite bands. The formation thickens northwards. Utnes Formation, 80m. This formation is transitional between the Conqueror and the underlying Roysha Formation. The distal turbidite facies, especially of the Barents Formation but also elsewhere in the Grampian Group suggest by litho-correlation with the Hohnsletfjella beds of

167

Scotia Group (Late Vendian-Ediacara)

Tyrrell (1924) and M a j o r , H a r l a n d & Strand (1956) referred to this as the M o u n t Scotia series and A t k i n s o n as the Scotia G r o u p . It is defined by the following three formations.

Roysha Formation c. 400 m. The Roysha Formation is of very soft black carbonaceous slate interbedded with dolomite siltstones. Manby (1986) referred to this unit as the Omondryggen formation. Kaggan Formation c. 300 m. The Kaggan Formation consists of tight isoclinally folded slate phyllonites. The distinctive green and purple striped slates suggest a minor volcanic component metamorphosed with chloritoid. Baklia Formation. Exposed near lake Baklia in a passage downwards from black slates with quartzites to a black carbonaceous slate sequence containing grey-orange dolomitic limestones with inraformational breccias. The lower part of the formation consists of grey, frequently cherty, dolomitic siltstones with black slates. Below this are quartzites, frequently conglomeratic, with green and black slaty laminae and then dolomitic cherty limestones. When the sequence, described here from Prins Karls Forland, was published no fossils had been found in situ on the island. However, the cherts in the Baklia Formation, referred to as the Black Carbonate Pelite (BCP), have yielded microfossils (Knoll & Ohta 1988). The dolostone is oolitic in places. The following taxa were described and figured. Eomycetopsis robusta Schopf, emend. Knoll & Golubic (1979); Eomycetopsis sp.; Siphonophycus inornatum Zhang; Siphonophycus sp.; Myxococcoides sp.; Obruchevella Reitlinger (1959); ?Obruchevella sp. Poorly preserved acritarchs include leiosphaerid-like vesicles and rare spheres with vesicles and with an outward layer of hollow processes, typical of Late Riphean and Vendian strata in Russia; of the Doushantuo Formation of central China and of the Pertatateka Formation of central Australia, these occurrences being of latest Proterozoic age. Knoll & Ohta (1988) concluded that 'the most likely age for the BCP beds is Late V e n d i a n - i.e. post-tilloid but Precambrian in age' and they stressed the uncertainty of this age because Hjelle, Ohta & Winsnes (1979) had placed this unit below the tillite horizon. From their localities on the map Harland, Hambrey & Waddams (1993) matched the lithology with the Baklia Formation. It seems that the BCP of Knoll & Ohta is the Black Shale Formation of Hjelle et al. (1979). It is likely that these units belong to the Scotia Group. Whatever the detailed stratigraphy, Prins Karls Forland thus contains the first Ediacara biota to be recorded in Svalbard. This age fits well the sequence of Harland et al. (1979).

9.6.3

Peachflya Group

These rocks were first n a m e d by Tyrrell the Ferrier Peak Series a n d m a y have been referred to by A t k i n s o n as the K e r r G r o u p . It was defined by four f o r m a t i o n s w h i c h were defined by H a r l a n d et al. (1979) and followed by H a r l a n d , H a m b r e y & W a d d a m s (1993).

Knivodden Formation, 400 m. Incompetent chloritoid phyllites pale grey, dark grey and pale green. Hornnes Formation, 350m. Siliceous-phyllite, sandstone quartzite, limestone alteration. Alasdairhornet Formation, 190m. Volcanic suite- banded and welded tufts with some basic lava flows. Thin carbonate interbeds occur near top and base, marked by reworked volcanogenic and siliciclastic material. Fisherlaguna Formation, 350 m. Incompetent blue phyllites.

9.6.4

Geikie Group

This g r o u p ( H a r l a n d et al. 1979 following Atkinsons, 1960, name) unlike the overlying groups has thrust r a t h e r t h a n sedimentary contacts at the b o t t o m .

Rossbnkta Formation (>300 m) of dark siliceous phyllite which becomes increasingly calcareous towards the base.

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Gorden Formation (>470 m). Calcareous phyllite with 3 to 4m massive dolostone-limestone laminated horizons with intraformational breccias, carbon-rich beds, and pisolitic limestones.

9.6.5

Ferrier Group

The Ferrier Group comprises four formations. All are typically schistose diamictites of biotite grade. They have been interpreted (Harland et al. 1979) as distal flyschoid marine tillites. They dominate the mountains of central Prins Karls Forland south of Selvgtgen.

Neukpiggen Formation (270 m). Consists of calcareous and chloritic schist with discontinuous psammite, marble and conglomerate beds. Dispersed dolostone and quartzite stones occur throughout the schist and phyllite. Granite stones 10 mm to 0.4 m long and marble stones 50-100 mm long were recorded. Small folded psammite blocks suggest slumping, pene-contemporaneous erosion and resedimentation at some horizons. Peterbukta Formation (160m). Comprises pink-, grey-weathering, psammitic schist, grey calcareous schist and dark pelitic schist with discontinuous beds of clear crystalline psammite and dolostone orthoconglomerate, and intraformational conglomerates. Outsize stones occur throughout. Hardiefjenet Formation (120-500m). Upper division of pale, calcareous siliceous schist and lower division of dark green schist. Similar to Neukpiggen Formation but darker in colour and higher metamorphic grade. Isachsen Formation (> 150 m). Consists of dark green quartz chlorite schist with brown interlayers and numerous pressure solution quartz segregations. Thin layers of diamictite occur, but mostly thin-bedded or laminated and somewhat sorted. Beds of tuff 1-2 m thick are disposed through the formation. The base is not exposed. Alfred Larsentoppen Unit. In addition to the main outcrop there is an isolated klippe on Alfred Larsentoppen - the only such diamictite north of Selvgtgenand Scotiadalen. The upper 20 m are of orange weathering, coarse dolomitic psammite with dispersed stones of grey dolostone - more numerous and larger than in the four formations described above. The lower unit is rich in granitoid boulders. Because both of their granitoid content and their stratigraphic position we correlate all these tilloids with the Comfortlessbreen Group; that is the Later Varanger glacial episode (Mortensnes).

9.6.6

Pinkie Formation

The Pinkie Formation occurs as a thrust slice between overlying Conqueror quartzites and underlying Geddesflya siltstones and quartzites. It consists of quartz biotite schist, feldspathic magnetite biotite schist, felsite, and a calcareous brecciated slate rich in biotite. The formation is of higher metamorphic grade than any other rocks recorded on the island and, as it does not match any of them closely in composition, it has been presumed to be a slice of an older complex. Considering the mainland succession, the strata preceding the Comfortlessbreen Group diamictites are rich in basic igneous material. This suggests that the Pinkie Formation was derived by (?Ordovician) metamorphism from the Lovliebreen Formation (Harland, Hambrey Waddams 1993; Ohta et al. 1995) in the St Jonsfjorden Group. So in this work it would be part of the Early Varanger sequence

9.7

Structure of Oscar II L a n d

Triassic through Carboniferous strata crop out extensively in northern and eastern Oscar II Land and their deformation displays the structure of the Paleogene West Spitsbergen Orogen. In Western Oscar II Land the pre-Carboniferous basement was affected by at least one earlier tectonic episode as well as by the Paleogene orogeny. Oscar II Land is a prime region for the study of structures related to the West Spitsbergen Orogeny (e.g. Orvin 1934; Challinor 1967; Maher 1988; Manby 1988; Winsnes & Ohta 1988; Bergh & Andresen 1990; Bergh et al. BSG, 1993; Andresen,

Bergh & Haremo 1994; Bergh, Braathen & Andresen 1997). Localized structural studies have been carried out in three areas: Broggerhalvoya in the northwest, eastern St Jonsfjorden in the centre, and the Lappdalen/Mediumfjellet area in the southeast. Most of the interior has been mapped from aerial photographs, but many western parts have yet to be mapped in detail. Oscar II Land is divided here into four areas: northwest, southwest, centreeast and centre-west (9.7.1-9.7.4).

9.7.1

Northwest Oscar II Land

Broggerhalvoya and Kongsfjorden. Broggerhalvoya is located in the northwest part of Oscar II Land and represents a significant change in the vergence of structures in this orogen, from an essentially easterly to a northerly vergence. This is particularly evident along the southern margin of Kongsfjorden, where structures tend to strike parallel to the coast (Challinor 1967). The area between Broggerhalvoya and Engelskbukta in the northwest part of Svalbard illustrates the involvement of basement (pre-Devonian) in the Paleogene fold-and-thrust belt. The large-scale structure of the area consists of a series of northto northeast-vergent thrust nappes dominated by post-Devonian strata in the northwest part of Broggerhalvoya and by preDevonian strata in the southeast part of the peninsula, Engelskbukta and northern Oscar II Land. A major N-S-trending fault zone in the vicinity of Broggerbreen (referred to as the Scheteligfjellet Fault Zone by Challinor (1967) separates the nappes in the northwest from those to the southeast and south, but does not continue into the structurally higher nappes of the southern part of the area. Manby (1988) interpreted this structure as a transfer zone along which the more northerly displacement of the southeastern nappes has been accommodated by sinistral shear. In northwest Broggerhalvoya, the younger rocks are stacked into three major nappes. The Broggertinden Formation is deformed into broad open folds along the Kongsfjorden coastline indicating that the floor thrust to the lowest exposed thrust nappe is ramping up at this point (Manby 1988). Structures within the Wordiekammen Fm are well exposed in Scheteligfjellet, with the upper duplex considerably more deformed than the lower. The whole of the higher nappe is folded into an overturned, north-vergent, anticline-syncline pair, where a late thrust repeats part of the lower limb of the syncline that carries Gipshuken over Kapp Starostin rocks. The highest of the three nappes in the northwest comprises a pre-Devonian to Early Permian sequence that is floored by a low-angle south- to southwest-dipping thrust, where the high cut-off angle between this thrust and the steeply dipping, overturned hangingwall rocks indicates that overfolding preceded thrusting. According to Manby (1988) a minimum of 12 km of shortening is necessary to account for the deformation in the uppermost nappe, and at least 18 km when taking the whole nappe sequence in northwest Broggerhalvoya into consideration. To the southeast of the Broggerbreen Fault, the lowest nappe contains a sequence of Paleogene to Broggertinden (Bashkirian age) strata that are folded into a broad northwest-plunging syncline which is itself overthrust by the recumbent Zeppelinfjellet syncline. This thrust sheet is characterized by small-scale imbricates, duplex structures and folded thrusts (Challinor, 1967). The pre-Devonian rocks in the overthrust sheet consist of metamorphic rocks of the Kongsvegen Group (Harland et al., 1979), the whole sequence being characterized by a well-developed anisotropy with shear fabrics and mylonitic zones refolded on various scales by north to northeast vergent crenulation-type folds, consistent with Paleogene deformation of the lower nappe. Moefjellet marbles have been strongly deformed into an imbricated sequence above the Trondheimfjelletnappe and are unconformably overlain by a synclinally folded and cleaved sequence possibly of Billefjorden Group at the head of Nordenfjeldskebreen. Waddams (1983) noted that these rocks were subsequently overthrust by the Haaken tillite succession. To the southeast of the col, at the head of Nordenfjeldskebreen, the Haaken and Moefjellet rocks are defined by thrusts in which Alkhorn marbles also became incorporated (Harland et al., 1979). The presence of post-Devonian rocks in the higher nappes and identical vergence directions in both sequences indicate that the deformation of the pre-Devonian rocks is related to the Paleogene West Spitsbergen Orogeny.

CENTRAL WESTERN SPITSBERGEN

Kongsvegen to St Jonsfjorden.

The area between Comfortlessbreen and Sarsoyra is defined by a shallow southwest sheet dip of the Haaken tillites. Along the southern shore of Engleskbukta the Caledonian S1 foliation is refolded by open box-like folds overturned to the northeast, with a characteristic pressure-solution cleavage developed. Interpreting the structure of the pre-Carboniferous basement depends on some knowledge of its stratigraphy. Harland, Hambrey & Waddams (1993, p. 56) outlined a scheme for Oscar II Land with a tentative thrust extending from the snout of Comfortlessbreen southeast through Lovenskioldfonna to make stratigraphic sense; but there are many more faults. Detailed mapping is awaited. On this interpretation the thrust would be consistent with a Paleogene dextral transpressive motion. To the west of Kapp Graarud, Tertiary conglomerates lie above the pre-Devonian strata, with both sequences cut by steep westdipping to vertical faults, striking broadly N-S. The conglomerates show small-scale sinistral and dextral displacements of pebbles that can be related to anastomosing fractures parallel to the faults. Ohta et al. (1995) described the structure of Sarsoyra and Kaffioyra as a complex strike-slip fault system with variable orientations of each domain as evidence of dextral transpression in a deep shear zone.

9.7.2

169

conglomeratic horizons containing clasts showing evidence for a pre-depositional deformation fabric. The immature nature of the Bulltinden Conglomerate suggests rapid deposition from a local source. The presence of the conglomerate indicates that there was a significant uplift phase. The timing of deposition is derived from the late Llandovery to Wenlock ages of the, the Motalafjella Limestone, lowest formation of the Bullbreen Group (Scrutton et al. 1976). Svalbardian (Late Devonian) movements, sinistral transpression according to Harland (1985), was later than deposition of the Bullbreen Group. Kanat (pers. comm.) suggested that the Bullbreen Group should have suffered some degree of deformation. This episode may have been concentrated in the shear zones. Tight small scale sinistral isoclinal folds are conspicuous in the westernmost outcrops of Daudmannsodden in southwest Oscar II Land (Harland, Hambrey & Waddams 1993). This would imply, therefore, that younger sediments deposited on the Bullbreen Group should be in unconformable contact, although this type of contact has not been identified. Weiss (1953) identified an unconformity at the base of the Carboniferous rocks where they were in contact with lithologies associated with the metamorphic complex. However, a sedimentary contact between the Bullbreen Group, of inferred Silurian age, and younger rocks has yet to be recognized. It is unfortunate that the outcrop of Bullbreen strata is limited to so few exposures.

Southwest Oscar II Land

Weiss (1953) identified two deformation phases in the preDevonian basement rocks to the south of St Jonsfjorden. Horsfield (1970) similarly defined two major phases, corresponding to Paleozoic and Paleogene events. More recently, K a n a t & Morris (1988) suggested a more complex tectonic history.

The Eidembreen phase (D1 of Kanat & Morris 1988) of early to mid-Ordovician age. Throughout southwest Oscar II Land, the metamorphic complex, particularly that of the Vestg6tabreen Formation, exhibits evidence of an intense deformational phase; this episode also produced a penetrative cleavage (S1) and related metamorphism. Structures such as folds and boudinage, which have a consistent relationship to S 1, are attributed to D 1. The style and intensity of folding, as well as the development of the S 1 fabric, is inhomogeneous and can be attributed to the largely anisotropic behaviour of the basement rocks. The following is based partly on Kanat (pers. comm.). The penetrative $1 cleavage is variably developed in the preCarboniferous Vestg6tabreen Fm as a mineralogical banding, particularly in the more massive lithotectonic units such as the brecciated dolostone, psammite, eclogite and serpentinite divisions. The S1 fabric has a variable orientation throughout the area to the south of St Jonsfjorden, although in general many of the platy metamorphic minerals are parallel to S1. On the mesoscopic scale the mineralogical banding in the psammite division is correlated with the S1 fabric of the associated divisions of the Vestg6tabreen Fm. SO (bedding) if preserved is expressed as helical inclusion trails in garnet porphyroblasts; in general SO is indistinguishable from S1 within the metamorphic complex, i.e. they are parallel. Inclusion trails within garnets, flattened chloritoid rosettes and the alignment of amphiboles and mica, suggest that metamorphism was pre- to syn-D 1. On the megascopic scale, D1 is associated with metamorphism, uplift of the Vestg6tabreen Fm, and thrusting and folding of the metamorphic complex. The general positions of the main lithological units of the metamorphic complex (i.e. the Comfortlessbreen Gp to the west and the St Jonsfjorden Gp in the eastern part of the St Jonsfjorden area), and the development of the (now) tight asymmetric folds within the metamorphic complex were formed at this time. The vergence of minor folds within the Vestg6tabreen Fm shows no significant correlation with that of the major fold structures (e.g. at Motalafjella) and they are therefore of different ages. Similar structural fabrics to those recognized in the Vestg6tabreen Fm are also found in the Comfortlessbreen and St Jonsfjorden groups. The Bullbreen Group was deposited later (Caradoc to Wenlock). This group has a distinct molasse-type character with major

Tectogenesis of the Eocene West Spitsbergen Orogeny. This second main deformational phase (Spitsbergian) accounts for the present structural pattern in Oscar II Land, with most of the large-scale structures, folds and thrusts so generated (D2 of some authors). This phase may have produced a well-defined cleavage ($2) in the finergrained horizons (fine sands and slates) of the Bullbreen Group. The coarser lithologies of this group (sandstones and conglomerates) are strongly cleaved in some areas, but not in others, although cleavage is generally evident to some extent. Sedimentary structures (e.g. crossbedding, graded bedding, sole markings, flame structures and ball and pillow structures), vergence directions and bedding-cleavage relationships indicate large-scale stratigraphic inversion, particularly along the Skipperbreen-Vestg6tabreen ridge and Motalafjella. F2 folds show gently to moderately dipping axial planes and fairly tight fold geometries, with wavelengths of 0.5-1 kin. Bedding and cleavage are poorly defined in the Motalafjella Limestone, and the orange-weathering dolostone unit lacks any internal structure. The Bullbreen Group was not affected by the mid-Ordovician orogeny (D1). Weiss (1953), in contrast, did not distinguish the Bullbreen Group from the metamorphic complex and therefore suggested that the structures in southwest Oscar II Land were related to a mid-Paleozoic orogeny. Evidence for a mid-Paleogene age for the basement structures attributed to the D2 phase comes from the following observations. (a) Fold wavelengths of deformed Carboniferous rocks at Broggerhalvoya are similar to those in the Bullbreen Group. (b) The orange-weathering dolostone unit may represent a mineralized thrust zone, typical of Paleogene thrusting (Harland et al. 1979). (c) The east-verging emplacement directions are consistent with the regional plate tectonic regime in the North Atlantic and Arctic regions during early Tertiary time (Harland 1965, 1966; Wilson 1965; Horsfield & Maton 1970; Pitman & Talwani 1972; Talwani & Eldholm 1977; Eldholm et aL 1984). (d) Part of the Bullbreen Group is of mid-Silurian age (i.e.) Post-D1. (e) The Bulltinden Conglomerate contains clasts with a pre-depositional deformation fabric. (i.e) post-D1. (f) The Bullbreen Group shows one less deformational fabric than is evident in the metamorphic complex (Morris, 1988) (i.e) Post-D1. (g) Based on fold geometry, dip direction of fault zones and truncations of lithological units of the Bullbreen Group, the emplacement direction of thrust and fold nappes was inferred by Kanat (1985) to be towards the NNE; this is supported by stretching lineation data within the Bullbreen Group (Ratliff, Morris & Dodt 1988). The orange weathering dolostone unit is inferred to have developed along thrust zones during D2 time and forms the

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CHAPTER 9

discordant zone between the Vestg6tabreen Complex and the base of the Bullbreen Group (Ohta et al. 1983; Morris 1988; Kanat & Morris 1988). The rock is commonly brecciated and the interstices are filled with a light grey limestone derived from the Motalafjella Formation. Quartz grains show evidence for strong deformation (deformation bands, deformation lamellae, undulose extinction and a shape fabric). Overall the chemistry and structural and metamorphic styles indicate a close relationship to the Vestg6tabreen Complex. This unit is best developed in the overturned limbs of major folds where the Bullbreen Group is separated from the Vestg6tabreen Fm. It is well exposed at southern Bulltinden, but also occurs at southern Holmesletfjella and Motalafjella. In addition, Ratliff et al. (1988) noted the presence of a heterogeneous mylonitic fabric that indicates a detachment zone for northeasterly directed folding and thrusting of the Bullbreen Group over other basement units (Morris 1988). To the south of St Jonsfjorden the Bullbreen Group and underlying dolostone are folded into a recumbent synformal syncline below the overthrust Vestg6tabreen Complex (Ratcliff, Morris & Dodt 1988). Ratliff et al. (1988) suggested that the Bullbreen Group was deposited within a fault-bounded linear extensional basin related to uplift of the Vestg6tabreen Complex as part of a convergent orogenic wedge. Continued contraction forced both the Bullbreen and Vestg6tabreen units over the underlying pre-Devonian shelf and basin sediments. They argued (p. 341) that the Bullbreen deformation was pre-Carboniferous on the, possibly doubtful, evidence that the Carboniferous rocks (sandstones and conglomerates) to the west of the Bullbreen outcrop do not share the Bullbreen penetrative tectonic fabrics. The structure is conspicuously over-thrust to the N N E (with the Vestg6tabreen Complex), with elongation of pebbles in the conglomerate parallel to the fold axes (WNW-ESE) direction with a shear displacement (transpression) of 4 km. The structures could certainly be D2 on the above system, only the age remains uncertain. If the timing of Ratcliff et al. is correct, a major deformation similar to that of the West Spitsbergen Orogeny occurred after the Eidembreen event (taken by some as D1) and before the Carboniferous Cretaceous succession deformed in the Paleogene West Spitsbergen Orogeny. This could be a Devonian event, but dextral rather than sinistral, and for which no other such intense tectonism is known in the west. Alternatively the structure, which conforms in most respects with those of the West Spitsbergen Orogen (thrust and fold belt) would be Eocene as favoured here. In this case the dextral transpression would match the model of a Paleogene transpressive orogen. Indeed, on this basis the dextral transpressive structure described in detail by Morris (1988) would be Paleogene and not Paleozoic. Moreover two phases are distinguished: (i) a N S compression with concomitant dextral strike-slip and (ii) easterly directed thrusting. A late stage event within the West Spitsbergen Orogeny and associated with the development of N-S normal faults, and also with the development of broadly E-W-trending strike-slip faults (Waddams, 1983) has been distinguished as a later phase within D2. This phase is not easily distinguished from the more evident D2 phase (Manby 1978). Though Kanat (pers. comm.) described a later D4 event, there is only clear evidence for the three principal events discussed here but their age attribution is not altogether reliable. There is a further consideration. At F a r m h a m n a (SW of the snout of Idembreen) the strata are vertical with a NNW-SSE-strike and are clearly tectonized in some degree. However limestones with Carboniferous corals to the west are concordant with Early Varanger tillites to the east over a short distance as seen in cliff sections. This suggests an absence of any regional Vendian through Devonian (Caledonian) orogeny. The most recent available study (Maher et al. 1997) focused on the strip of mainly Carboniferous rocks, within pre-Carboniferous basement, extending parallel to the Spitsbergen Orogen from St Jonsfjorden to Isfjorden, along the eastern margin of the Forlandsundet Graben (their Svartfjella, Eidembukta, Dandmannsodden lineament). It is faulted throughout and clearly belongs to the Spitsbergian tectogenesis. They interpreted a sequence of phases:

1 E N E - W S W contraction; 2 orogen-parallel sinistral motion; 3 dextral orogen-parallel motion. Their study related the three phases to those somewhat different interpretations of graben history by Lepvrier (1990), Gabrielsen, Grunnaleite & Ottesen (1992) and Teyssier, Kleinspehn & Pershing (1995) and of the origin in Nordenski61d Land to the south by Braathen, Bergh & Maher (1995).

9.7.3

Central and eastern Oscar II Land

Structural observations in the interior of Oscar II Land are still mainly based on reconnaissance mapping and on the interpretation of aerial photographs (Challinor 1964; Harland & Horsfield 1974; Maher 1988a, b), although new data on eastern parts have been presented (Bergh et al. 1988a, b; Bergh & Andresen 1990; Bergh et al. 1993; Wennberg et al. 1992, 1994) and demonstrate the typically thin-skinned style of deformation. Maher (1988a, b) compiled a regional structure map of central and eastern parts, and identified three zones of distinctive structural style or geometry as follows. (i) A zone characterized in the north by thrusts with a complex geometry emplacing pre-Devonian rocks into and over the lower cover strata (Broggerhalvoya to St Jonsfjorden). In the south this zone is characterised by a series of stacked monoclinal to overturned folds of Kapp Starostin Formation strata, forming a 'staircase' geometry. (ii) A central zone characterized by folds within upper Kapp Starostin Formation and Triassic strata without obvious major thrusts (displacement greater than 1 km). (iii) A zone with at least two major thrusts that have emplaced Kapp Starostin Formation strata over Triassic strata. Fold geometries may be correlated with fault-bend folds, with angular hinges and flat tops (Suppe, 1985); smaller thrusts are also evident. The apparently regular and consistent orientation of many of the fold structures within the interior parts of Oscar II Land are a direct reflection of underlying fault geometries. The nature of the underlying structure is inferred as ramping in the pre-Devonian rocks, propagating, and flattening out in the weak gypsum horizons of the Gipshuken Formation; all slip would therefore be transferred along this horizon farther east (Harland, Mann & Townsend 1988; Maher 1988b). The central zone of folding displays open to tight folds in Kapp Starostin Formation and Triassic strata, with varying styles from conjugate to more rounded forms. Considering the mechanical competence of Kapp Starostin Formation strata it is unusual to find such tight fold geometries, e.g. to the south and west of Isfjorden (Maher & Welbon 1992). According to Maher (1988b) the folds interpreted from aerial photographs have neutral vergence, with axial planes essentially vertical; numerous small thrusts are likely, but large thrusts (displacements greater than 1 kin) are absent in most areas. The Kapp Starostin Formation upper boundary is identified repeatedly at the surface suggesting a sub-horizontal, envelopment surface for the folds, the implication being an underlying subhorizontal detachment. The gypsum horizons within the Gipshuken Formation form an obvious candidate for the underlying detachment (Harland & Horsfield 1974; Harland, Mann & Townsend 1988), and thus the gypsum horizons promote a zone of thin-skinned deformation. The folds that form above this 9-10 km wide detachment may represent buckle folds (Maher 1988b). Such a simple model, assuming concentric fold geometries, necessarily implies space problems at depth. On the basis of idealised fold geometries, Maher suggested that a perfectly concentric fold geometry provides an upper limit for the shortening estimate, for which estimates lie in the range 14-25% (of original length) with an average linear shortening of 2.2 km (about 20%) across the width of the central zone. The inferred depth to detachment is calculated to be in the range 364-694m and is consistent with a basal detachment within the lower parts of the Kapp Starostin Formation, or more likely within the underlying Gipshuken Formation (Challinor 1967; Maher 1988a, b).

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The Lappdalen-Mediumfjellet segment. The Lappdalen-Mediumfjellet thrust front in east Oscar II Land presents a structural profile through the stack of thrust sheets allowing an interpretation of the geometric relationship between the folding and thrusting; a detailed analysis was given by Bergh & Andresen (1990). Figure 9.6, summarized from that paper, shows the essentials of the structure. They described their traverse under the following heads from east to west.

(a) The Mediumfjellet-Lappdalen thrust front with west dipping stacked and imbricated thrusts with repetition of Sassendalen, Kapp Starostin and Gipshuken units. Incompetent Triassic strata display upright folds but the competent Permian strata form large amplitude chevron and box folds. Decollement zones select the incompetent Gipshuken and Botneheia Formations. (b) The Lappdalen transition zone about 2 km wide separates (a) and (c). (c) The Lappdalen fold and thrust zones. Four distinct thrust or fold structures were described (Bergh & Anderson). They are interpreted as the leading edge in an eastward propagating thrust system, based in a sole thrust within the Gipshuken Formation with advancing piggy-back thrusting. (d) The Mediumfjellet fold and thrust zones also exhibit four thrusts, with box-like disharmonic folds based on the Gipshuken evaporite zone, generally dipping west. Analysis of these profiles extending 10km E-W by balanced sections gave a minimum shortening of 4 km. Blind thrusts, hidden detachments or out-of-sequence thrusts would increase this estimate.

The T r y g g h a m n a - L a p p d a l e n segment. Structural mapping of Paleozoic and Mesozoic rocks in Oscar II Land within the West Spitsbergen Orogen, reveal a system of major asymmetric to overturned, east-vergent folds with NNW-SSE-trending axes, a c o m m o n feature throughout the orogen in this area. In addition the folds are accompanied by complex thrust faults and imbricates with a shallow to moderate southwesterly dip.

Structural studies in the Trygghamna-Lappdalen area of southern Oscar II Land reveal a variation in the geometry of the major folds, from asymmetric with wavelengths of up to 2 km, to typical chevron and box-like geometries. The movement along frontal ramps generated complex folds, stacked imbricate thrusts and associated backthrusts and backfolds within the Mesozoic (Triassic) cover. There is a clear genetic relationship between folding and thrusting where thrusts die out or pass along strike into major folds. Most of the imbricated thrusts developed by forelimb cut-offs of inverted major folds, with the imbrications producing numerous repetitions of sandstone-dominated Triassic formations in the area to the north of Erdmannflya. The Permian layers contain most of the mapped frontal ramps since these units are mechanically more competent, but flatten or sole out in the less-competent shaly Mesozoic formations, e.g. the Botneheia Fm and Janusfjellet Subgp. A major NE-SW-trending and essentially vertical strike-slip fault, the Isfjorden Fault (Challinor 1967; Harland & Horsfield 1974), separates highly deformed Mesozoic rocks to the northwest from the largely flat-lying Cretaceous/Tertiary rocks to the southeast on Erdmannflya and is interpreted as an oblique ramp structure (Bergh et al. 1988). The rocks adjacent to the fault (Cretaceous and Tertiary strata) are characterized by numerous

minor reverse faults, imbricate thrust sequences and tight upright folds with an axial planar cleavage. The throw on this fault is approximately 400 m based on the correlation of the Jurassic-Cretaceous boundary in the hanging-wall and footwall blocks. Bergh & Andresen (1990) proposed a model for the Paleogene structure of Oscar II Land whereby compressional deformation is transferred eastwards by a combination of fault propagation folding and thin-skinned d6collement thrusting. The western area can be considered a buried/blind thrust system. To the northeast the deformation style is typically that of an emergent thrust system with fault propagation folds and thrusts reaching the surface; similar structural styles are observed in Mesozoic rocks of Nordenski61d Land and along the Billefjorden and Lomfjorden fault zones of eastern Spitsbergen (Andresen, Bergh & Haremo 1994; Nottvedt et al. 1988). The implication is that a thin-skinned tectonic model can be applied to the West Spitsbergen Orogen in eastern Oscar II Land, in which orogenic stresses within the main part of the fold-and-thrust belt are transferred eastwards to the more central areas of Spitsbergen by regional d6collement or detachment beneath the Central (Paleogene) Basin (Nottvedt et al. 1988; Bergh & Andresen 1990).

9.7.4

The St Jonsfjorden area

The St Jonsfjorden area of West Spitsbergen lies within the Tertiary fold-and-thrust belt and has been studied by Horsfield, Kanat, Welbon & Maher (1992) and Maher & Welbon (1992). In the eastern part of the St Jonsfjorden area (Wittenburgfjellet to Klampen), Permian Kapp Starostin Formation cherts and limestones and the Triassic Sassendalen Group shales and sandstones form large northeast-vergent, close to tight folds within which smaller thrusts are common. Further west, Kapp Starostin Formation strata and underlying Gipsdalen Group strata are imbricated and form duplexes that underlie large-scale northeast-vergent monoclinal structures. Welbon & Maher (1992) summarized the St Jonsfjorden region, and supplement the earlier work of Horsfield. Mann & Townsend (1989) suggested a simple model whereby the St Jonsfjorden Trough formed in the hanging wall of the west-dipping fault zone, with the southern margin of the basin offset by a major NW-SEtrending transfer fault in Van Keulenfjorden. Vegardfjella and Wittenburgfjella (southeast end of St Jonsfjorden) are on the eastern edge of the basement high that parallels the west coast of Spitsbergen. Mapping (by Challinor & Horsfield, CSE) indicated a northeast-vergent thrust stack involving basement rocks and platform cover strata including Triassic units (Welbon & Maher 1992). Three major thrusts were defined by Maher & Welbon (1992) in the Vegardfjella-Wittenburgfjella area of inner St Jonsfjorden: the Lower Vegardfella Thrust, the Upper Vegardfjella Thrust, and the Vegardbreen Thrust (see also Welbon & Maher, 1992). This is a complex structure with units separated by the three thrusts mapped namely: Lower and Upper Vegardfjella thrust and the Vegardbreen thrust.

172

CHAPTER 9

Vegardbreen Thrust.

The Vegardbreen Thrust is the most prominent structure in the southern part of Oscar II Land. The thrust geometry is complex with significant Wordiekammen and Botheheia formation flats and a truncated, overturned fold limb with numerous minor structures in the eastern hanging-wall. The overall northeast dip is due to rotation above the underlying thrusts. The Vegardbreen Thrust was interpreted by Welbon & Maher (1992) to be the roof thrust with which the Upper Vegardfjella Thrust merged.

The repetition of Permian Kapp Starostin and Triassic strata to the northeast of Wittenburgfjellais mainly due to folding, but with the occasional development of minor thrusts; this is particularly evident at Klampen where six fold pairs are present. This zone of folding is about 8 km wide and was interpreted to have formed above a flat within the underlying Gipshuken Formation gypsum (Harland & Horsfield 1974; Maher 1988; Bergh & Andresen 1990). If this interpretation is correct, the eastern zone is clearly thin-skinned in character, which contrasts with the Vegard thrust stack where basement rocks are involvedin the thrusting and significant thrust ramps exist. Shortening across the Vegardfjella and Wittenburgfjella area was estimated to be about 13 km (Welbon & Maher 1992).

9.8

Structure of Prins Karls Forland

Whereas Oscar II Land exposes pre-Devonian and Carboniferous through Cretaceous strata, and so enables a distinction to be made between pre-Carboniferous and post-Early Cretaceous deformation, Prins Karls Forland lacks post-Silurian strata. Therefore suspected Paleogene deformation cannot be confirmed nor characterized by tectonism in younger strata. As in Oscar II Land, however, a post-Vendian pre-?Silurian tectonism sufficient to produce schistose and phyllitic lithologies, seen in the Sutorfjella conglomerate clasts in a turbidite sequence (Barents Formation), may correspond to the mid-Ordovician (Eidembreen) event in Oscar II Land. The structure of Prins Karls Forland has been investigated by many authors (e.g. Tyrrell 1924; Atkinson 1956, 1960; Harland et al. 1979; Hjelle, Ohta & Winsnes 1979; Morris 1982, 1989; Manby 1983a, b 1986; Dallmann et al. 1993; Lepvrier 1990). The structure reflects the stratigraphy trending and striking generally N N W - S S E parallel to the long axis of the island. Dips are often steep but the thickness of the strata generally yields broad outcrops. Distinct folds may be observed in E-W cliff sections with typical asymmetrical and occasional recumbent folds. Each investigation resulted in a different stratigraphic sequence which affected the structural interpretation and vice-versa. Despite the many uncertainties in Prins Karls Forland geology this author is reasonably confident in the essential correctness of the succession worked out by the Cambridge group as in Section 9.6. However, the ages of most units are uncertain.

9.8.1

Sequence and age of deformation

Because of the prevailing Caledonian deformation in much of Spitsbergen it was natural to assume that strong tectonism in older (unfossiliferous) rocks would probably be Silurian if not older. Atkinson (1956) described his structures as Caledonian without question or evidence. Harland & Horsfield (1974) in establishing the West Spitsbergen Orogen as a Tertiary entity included Prins Karls Forland (with the Pre-Carboniferous rocks of Oscar II Land) as zones (1 and 3) of probably Caledonian basement in which it was difficult to distinguish the effects of the Paleogene Orogeny so evident further east in Oscar II Land. Harland, Horsfield, Manby & Morris (1979) concluded an agreed stratigraphy based on work by Harland and Horsfield in Oscar II Land, then Harland followed by Manby and Morris in Prins Karls Forland. Tectonic interpretation was developed by individual authors.

Hjelle, Ohta & Winsnes (1979) covering the same area (Prins Karls Forland and Oscar II Land) concluded a Tertiary age of deformation of the island in conformity with that of the mainland. Manby (1986) described 'mid-Paleozoic metamorphism and polyphase deformation of the Forland Complex'. He assumed a Caledonian structure interpreted in three phases D1, D2 and D3. He did not distinguish which rock groups exhibited which characteristics nor did he specify the criteria by which D 1 and D2 could be distinguished, they being essentially homoaxial. Whereas D3 was a mild tectonism thought to be Tertiary, the conclusion on D2 was somewhat equivocal. Morris from his (1982) map plotted the en Ochelon Scotiadalen fault zone and concluded (1989) that 'the relatively simple geometrical relationships and the lack of secondary modification of the Scotiadalen fault zone argue against a Paleozoic origin'. The distributed shear zone is well orientated to accommodate shear strain developed during Tertiary time, and probably formed prior to the transitional phase of this deformation (Late Eocene to midOligocene, say 40-30 Ma; Steel et al. 1984; Lepvrier et al. 1988). Lepvrier (1990), possibly following Harland & Horsfield, assumed that his Tertiary graben structure adjoined Caledonian basement. The conclusion here, in conformity with interpretations of other parts of the western terranes is that there is some evidence for an early metamorphic post-Vendian, pre-Silurian phase which could be part of the mid-Ordovician Eidembreen event. It would thus only be seen in four lower groups and not in the Grampian Group and some of the D 1 characters as described by Manby could be of this age. No evidence is available of Silurian tectonism and it is concluded here that the main tectonism was part of the West Spitsbergen Orogeny of Eocene age.

9.8.2

Vergence of deformation

Whereas all agree that the structural trend is NNW-SSE, hence the linear shape of the island, the vergence could be either way towards the ENE or the WSW; it is not immediately obvious. Authors adopted one or other direction to conform with their overall interpretation. Thus Atkinson (1956) and Manby (1986) thinking the structure was Caledonian chose the westward vergence independently of the Paleogene eastwards thrusting on the mainland. On the other hand Hjelle, Ohta & Winsnes (1979), treating the island in conformity with Paleogene structures of the mainland, opted for an eastwards vergence as was followed, without discussion, for the northern part of the island by Dallmann et al. (1993). Figure 9.7 shows somewhat different interpretations of the same structures. Manby's sections show a thin-skinned tectonic d e v e l opment on a floor thrust not far beneath the surface. This author's prejudice has been towards a westward vergence and this need not be inconsistent with a Paleogene age as is discussed in Section 9.10.

9.8.3

Faulting

(a) Sequence of faulting. The Scotiadalen N-S Fault shown on most maps is not a major fault but a zone of minor en ~chelon faults trending N N E which, as Morris (1989) demonstrated, was a late event. A map of pre-Carboniferous groups of southern Prins Karls Forland is shown in Fig. 9.8. The island is crossed by many faults, typically ENE to ESE which appear to cut most structures including the boundary faults of the Paleogene graben. No systematic displacement has been noted. The principal single feature on the island is the boundary between the older deformed strata and the relatively undeformed Paleogene strata of the Buchananisen Group. The boundary appears to be one main fault or a series of stepped faults dipping steeply into the graben. It does, however, differ from north to south. Cliff sections north of

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CHAPTER 9 The re-emergence of the Prins Karls Forland Block was largely the result of extensional displacements along NNW-SSE-trending faults, along which there is also evidence for oblique-slip and pure strike-slip movement (e.g. Lepvrier & Geyssant 1984; Lepvrier 1990). Structural evidence for this is the presence of southeast-plunging folds in the Tertiary rocks of Prins Karls Forland. The generation and orientation of these folds can be explained by a resolved NE-SW principal compression (rl) of the rocks resulting in an overall northward movement of Prins Karls Forland with respect to mainland Oscar II Land. The latest identifiable events on the island are the broad E-W flexuring and ENE-WSW faulting of the Forland Complex and Tertiary infill, which resulted in the displacement of the main NNW-SSE-trending fault (Manby 1986).

(c) Structural units. In the north of the island the major thrusts were used first by Atkinson and then by M a n b y to define (respectively) five and four tectono-stratigraphic sub-areas. The map from M a n b y (1986) in Fig. 9.7 shows the named thrusts and sub-areas numbered. The sections are not altogether consistent with observed stratigraphy on the ground, but the overall style of deformation may well be correct.

Fig. 9.8. Lithostratigraphic formations and geological map of south-central Prins Karls Forland (adapted with permission from Morris 1982, 1989). Selv~tgen show typical normal faulting. However, at the northern tip of the island the boundary, whether or not faulted, shows vertical concordance between Grampian Group strata and indurated Paleogene strata. This indicates certainly that some Paleogene strata were involved in a compressive-transpressive phase and possibly that it is an up-ended parallel unconformity. If the latter, this would be no surprise in so far as mid- or late Paleozoic tectonism has not been established in the western terranes. The main boundary fault, generally steep to ?vertical appears to cut the folds and thrusts of the core of the island. The thrust faults all belong to the same homoaxial folded structure and have not been distinguished by age. The following hypothesis develops from (a) this author's prejudice for westward vergence of the thrusting, (b) the structure south of Scotiadalen according to the map of Morris (1989) and (c) the thin-skinned tectonic interpretation (in principle though not detail) as depicted by M a n b y (1986). It is conjectured here that the lower three groups exposed in the south of the island, being relatively competent, were folded in a simple anticline. The upper two groups were thrust westwards over this arch with d+collement in the incompetent Scotia Group. This would distinguish the thinskinned structures in the north. The break in the plan of the island suggests that the southern anticline might have continued northwards to the east had it not been downfaulted in the graben. (b) Strike-slip components. Dextral displacements in the Scotiadalen fault zone have been noted above (Morris 1989). Hjelle, Ohta & Winsnes (1979) referred to sinistral components but without localities. Possibly they had in mind the strong sinistral shear seen at Daudsmannsodden on the mainland (Harland et al. 1993). On the island some stones in the Ferrier Group tilloids are elongated possibly in the same sense. These and other indications cannot be dated directly. It is, however, generally accepted that the West Spitsbergen Orogeny resulted from Paleogene dextral transpression. Sinistral shear would fit the hypothesis of major Devonian strike-slip faulting which might have operated along the Forlandsundet Graben and so focused the Paleogene shear zone.

The principal feature of Manby's four (northern) units or subareas are as follows from the top down. Sub-area 4. A large part is formed of an uninverted Scotia-Grampian group succession in the upper limb of a large, essentially flat-lying F1 fold, the lower limb and core of which are truncated and replaced by the Northern Grampian Thrust (NGT). Sub-area 3. The central part of northern Prins Karls Forland is occupied by rocks of sub-area 3. In the north, this unit is covered by the Tertiary sediments of the Forlandsundet Basin and in the far north it is overthrust by the Northern Grampian Thrust (NGT). Structurally the rocks (Geikie, Peachflya and Scotia gps) form an inverted sequence in the lower limb of an F1 fold with an essentially fiat-lying anticlinal fold closing to the west; however, further south in the Selv~gen area, the strata around the F1 closure are right way up. Two prominent klippe structures are present to the north of Selvgtgen where they are infolded with Scotia Gp rocks. Sub-area 2. This forms a laterally extensive tectonic unit in north Prins Karls Forland, comprising rocks of the Scotia and Grampian gps. The rocks occur in a southward-plunging synform which verges southwest, with the rocks forming an inverted succession (Manby 1986). Conglomerates, stratigraphically equivalent to those in sub-area 1 have been more intensely deformed when compared with those in sub-area 1 with axial ratios greater than 6:1 aligned parallel to the major fold axis. Sub-area 1. This thrust sheet is the structurally lowest tectonic unit, lying beneath the Western Grampian Thrust (WGT), and largely consists of Grampian Group rocks; Scotia Group rocks are restricted to a small area to the north of this sub-area. The succession is uninverted with no evidence for stratigraphic repetition by minor thrusts. F1 folds range in size from microscopic to large-amplitude structures, e.g. the box or kink-like folds in the south of sub-area 1.

9.8.4

Metamorphic environments

Northern Prins Karls Land. The presence of biotite in the youngest exposed rocks of the Forland Complex indicates that the minimum metamorphic conditions reached were biotite grade (Manby 1983b). The stability of the chlorite-muscovite-quartzchloritoid assemblage in pelites, the absence of staurolite, cordierite or almandine garnet (in strata up to and including the Ferrier Group) suggest that metamorphic conditions remained within the greenschist facies and largely within the biotite grade. There is some evidence for higher temperatures in the Pinkie Group as shown by the higher aluminium content of some amphiboles and the presence of scapolite and oligoclase (Anl7), though this could be compositional; these rocks were also within the greenschist facies. According to M a n b y (1983b) the ambient conditions of prograde metamorphism prior to the start of D1 were within the 380-560~ and 4.0-7.5 kbar range, equivalent to geothermal gradients in the range 18-23~ -1. These are in broad agreement with data published by Ohta (1978) and Morris (1982).

CENTRAL WESTERN SPITSBERGEN Atkinson (1956) discussed chloritoid in the Forland. According to Manby (1986) evidencefor metamorphism occurring before D1 comes from the presence of randomly orientated and rosette clusters of chloritoid and other chloritoid crystals with rotational inclusion trails suggesting some syntectonic growth. However, non-aligned syntectonic mineral growth is not unusual. The phlogopites and chlorites overgrow S1 with minor pressure shadow development in sub-area 3 indicating that metamorphism continued late into D1. Manby (1986) suggested that the formation of the Forland Nappe closely followed the peak of metamorphism, the development of which was facilitated by the elevated temperatures and fluid phase activity.

Southern Prins Karls Forland. Metamorphism was first discussed by Tyrrell (1924) who identified chloritoid and muscovite referring the rocks to the biotite zone and the chloritoid as a stress mineral which Atkinson (1956) amplified as associated with the thrusting. Morris (1982) considered four compositions and described and interpreted their mineral assemblages: carbonates, pelites, psammites and mafics. The metamorphism accompanied or preceded the first recognisable structural event. Subsequent structures were not accompanied by metamorphism. Carbonate lithologies (>60% carbonate minerals) with dominant calcite, dolomite and quartz, with tremolite and epidote related to thermal (contact) metamorphism muscovite and chlorite. Consideration of possible mineral reactions suggest that it was low grade. Pelites (15-50% quartz, >25% Mg-A1-Fe silicates, <60% carbonate). Phyllosilicates (muscovite, biotite, chlorite and occasional chloritoid) are dominant with a variety of accessories and variable quartz. The rocks exhibit green-schist facies assemblages, similarly low grade. Psammites (>50% quartz). After quartz the above assemblages occur as minor constituents. Production of biotite implies a minimum temperature of 300~ Mafies (>15% quartz, >10% carbonates, >75% Mg-A1-Fe silicates) These are essentially found as metavolcanic flows, tufts, other pyroclastics and mixed with other sediments. Temperatures between 380~ (5 kbar) and 520~ (7 kbar) have probably obtained in retrograde metamorphism with degassing. In conclusion, thermal isograds approximately parallel the stratigraphic boundaries. Tectonic depth of metamorphism is, of course, highly relevant; but there is nothing to suggest more than a minor orogenic episode.

9.8.5

Conjectural synthesis

Whereas there is stratigraphic continuity between the northern and southern segments of the island, their structural characteristics are quite different. Of the five groups of formations the upper two are limited to the north, the lower two to the south and only the Peachflya Group is common to both (Fig. 9.8). The major deformation of the whole island is taken here to be part of the Paleogene West Spitsbergen Orogeny. Paleozoic (?Ordovician) tectonic episodes and possibly Devonian sinistral shear zones are probably recorded in the rocks but have yet to be clearly distinguished. The main features of Manby's D1, D2 and D3 would be Paleogene as affecting all groups of strata, whereas the Grampian Group would probably be post-middle Ordovician. Boudinage, rodding and mullion structures seen in the Ferrier Group might reflect the Eidembreen Event or Late Devonian shear. It is provisionally accepted that a westward-vergent Paleogene Orogeny folded the three lower groups in a coherent, competent anticline, with a possible bedding thrust above the oldest Ferrier Group rocks. The Scotia Group strata are conspicuously incompetent and provided for some d~collement over the lower groups. The map suggests that the northern thin-skinned structures slid westwards over the older rocks, but the northern continuation of the southern anticline is cut out by the Paleogene graben. The Scotiadalen shear zone with its mild deformation would have been protected from the overriding transpressive thrusting in the shadow of the lower anticline.

9.9

175

Structure of the Forlandsundet Basin

The structure and evolution of the Tertiary Forlandsundet Basin is not well understood, largely because of its location along the axial zone of the West Spitsbergen fold-and-thrust belt (Gabrielsen et al. 1990; Steel et al. 1990). The dimensions of the basin are approximately 30 km wide and 80 km long. The palaeostress history of the Forlandsundet Basin has been attempted (e.g. Lepvrier & Geyssant 1983, 1985; Lepvrier 1990).

9.9.1

Structure of the infill

Early Paleozoic rocks. The tectonic m~lange exposed in scattered outcrops in Kaffioyra and Sarsoyra has been interpreted as a sheared body of distinctive rock types, with Motalafjellet deep facies affinities (Ohta et al. 1995). The implication is that probable Ordovician rocks have been sheared dextrally northwards in a steeply dipping zone. The dextral shear would indicate a Paleogene transpressive phase probably preceding most of the Paleogene strata whose deformation is the subject of section 20.6.3.

Paleogene strata. In the area of Selvfigen (Prins Karls Forland), on the western side of the basin, Kleinspehn & Teyssier (1992) noted contacts where Palaeogene sediments rest on a pre-Devonian palaeo-regolith. This led them to question the concept of a simple extensional graben with several kilometres of dip-slip offset on the boundary faults (e.g. Manby 1986). The basin fill also shows multiple thrusts, strike-slip faults, open to tight folds, refolded isoclinal folds and foliated shears. Some high-angle fault surfaces display slickenside striations indicating normal slip. The strata show a dominant dip toward the basin axis, but are locally overturned; the age relationship between various structures has not been resolved. Clastic dykes with slickenside striations and softsediment folding were inferred to indicate that deformation was in part coeval with basin subsidence and deposition (Kleinspehn & Teyssier 1992). Other faults studied by them were found to have cut and displaced conglomerate clasts together with the adjacent matrix, indicating a high degree of lithification at the time of displacement. Several generations of cross-cutting brittle deformational structures have been defined from within single exposures, indicating a multiphase deformation history. Kleinspehn & Teyssier (1992) reported widespread evidence of ductile deformation in the Tertiary strata at SelvSgen, Buchananryggen and at Sarsoyra on both sides of the Forlandsundet Basin. It occurs within single exposures indicating multiphase deformation under different tectonic/thermal conditions. Petrographic studies of sandstone samples indicated the development of a foliation and the recrystallisation of micas. Strain is localised along narrow ductile shear zones along which a macroscopic foliation is evident; microstructural work has shown that the foliation is pervasive but poorly developed away from the shear zones. Karen Kleinspehn (in an oral presentation in Oslo in 1990), suggested that the presence of dynamically recrystallized chlorite was evidence of growth at or close to the brittle-ductile transition (i.e. at about 10-15 km depth), the inference being that the Forlandsundet Basin cannot be considered a simple upper crustal graben as previously documented (e.g. Steel et al. 1985). Manby (1990) argued that if the sediments were buried to such great depths then there would be evidence for a thermal event within the pre-Devonian basement rocks and resetting of radiometric ages in Prins Karls Forland. No evidence for such an event is known. Gabrielsen et al. (1992) also demonstrated that the basin-fill has suffered stronger deformation than previously assumed. Syndepositional deformation is inferred to have occurred locally, with the basin-fill affected regionally by mild folding and locally by more intense brittle deformation; two fold sets are defined. High-angle reverse faults are common in some parts of the basin; the basin clearly shows evidence for compressional deformation. Intense

176

CHAPTER 9

d e f o r m a t i o n is localized in areas that are characterized by the r a m p i n g o f thrust faults; several systems of late extensional fractures are developed (Gabrielsen et al. 1990). K l e i n s p e h n & Teyssier (1992) as well as Gabrielsen et al. (1992) confirmed that, f r o m the degree o f lithification, the deposits on the western side o f the basin were buried m o r e deeply than those on the eastern side. Limited vitrinite reflectance d a t a f r o m conglomeratic beds in the Selvgtgen area show significant variations on either side of the F o r l a n d s u n d e t Basin. Vitrinite reflectance values (R0) on the west side of the basin are in the range 2.55-5.50 with an average of R0 = 4.01; in contrast, 20 k m away at Sarsoyra, values o f R0 = 0 . 4 3 - 0 . 4 6 are indicated (Rye-Larsen in SKS 1995). This indicates significant differential subsidence a n d differing thermal histories over relatively short distances, with the Tertiary sediments on the west side of Prins Karls F o r l a n d having been buried to a substantial d e p t h and well b e y o n d the oil w i n d o w (anthracite to m e t a - a n t h r a c i t e coal rank).

9.9.2

Palaeostress history of the Forlandsundet Basin (phases 1-3)

A n analysis o f faults in the F o r l a n d s u n d e t Basin a n d their use in determining the principal palaeostress tensors, has shown a polyphase tectonic d e v e l o p m e n t of the basin (Lepvrier 1990); and c o m p l i m e n t s the w o r k of K l e i n s p e h n & Teyssier (1992), Gabrielsen et al. (1992) a n d N o t t v e d t et al. (1992). The tectonic synthesis o f Lepvrier (1990) led on from earlier studies of the West Spitsbergen O r o g e n (Lepvrier & Geyssant 1984, 1985), w h i c h c o n c e n t r a t e d on n o r t h w e s t Oscar II L a n d and the F o r l a n d s u n d e t Basin area. The later study indicated that the basin has suffered b o t h extensional and compressional phases, the m a i n details of which are summarised below. Still later was the interpretation of the zone o f intense transpressional strike-slip causing scattered exposures on Sarsoyra and Kaffioyra on the east side (Ohta et al. 1995).

Phase 1: transpressional event.

Preserved horizontal fault striations (Steel et al. 1985) relate to a phase of broadly NE-SW compression, the N20 transpressional event of Lepvrier (1990).

Phase 2: E N E - W S W compression. This event gave rise to the basinward dip of the Tertiary strata; it generated a general synformal geometry to the basin. Seismic data across the basin also indicate a general synform structure (Nottvedt et al. 1990). The maximum compressional stress tensor (al) has an azimuth of 070 080 ~. Deformation related to this compressional event can be correlated on both sides of the basin, where rare tight folds or thrust faults, similar to those in the West Spitsbergen Fold Belt, are recognized (Lepvrier 1990). A component of dip-slip movement towards the basin axis can be observed at some localities, conformable with the bedding dip; according to Lepvrier (1990) this demonstrates that strike-slip faulting preceded tilting and represents the earliest stage of deformation under this stress regime. Along the eastern margin of the basin the alluvial fan conglomerates of the Sarsbukta-Sarstangen formations are affected by two sets of strike-slip faults. In the area of Sarsoyra (near Kapp Graarud and Nyflua) a set of dextral (035-070 ~ and sinistral (100-130 ~ faults, steeply dipping to the south and north respectively, are present, with striations indicating a component of normal displacement, caused by the later tilting of the strata. Conglomerate pebbles are cut and display a 1-2cm lateral offset. The faulted contact of the Tertiary strata with the pre-Devonian basement at Kapp Graarud is defined by a sinistral strike-slip fault (130 ~ that was active during this phase. In the Sarsbukta section, similar sets of faults are present, but extension (NW-SE to N-S) is generally dominant and defined by oblique to normal fault striations (e.g. at Sarstangen). The analysis of the dextral shear zone affecting the Kaffioya Ordovician basement (Ohta et al. 1995) confirmed the earlier interpretations. A similar stress pattern is evident on the western side of the basin at several localities, determined as 075 ~ from the existence of two sets of transverse (relative to the basin trend) strike-slip faults; locally some pebbles of the SelvSgen Formation conglomerate are laterally displaced (Lepvrier & Geyssant 1985; Lepvrier 1990).

Fig. 9.9. Simplified structural map and cross-sections of the Forlandsundet Graben (from Gabrielsen et al. 1992).

Phase 3: E S E - W N W and N N W - S S E to N - S extensional phases. Faults related to each of these extensional phases are sometimes difficult to distinguish. However, the final NNW-SSE to N-S extension is well defined by oblique to dip-slip movements on the two sets of earlier strike-slip faults, associated with the ENE-WSW compression; this extension eventually becomes a prominent tectonic event. At Marchaislaguna, faults striking 060-075 ~ and 095-115 ~ cut N W S E to N-S faults and show oblique striations that are inferred to relate to an extension direction trending 167 ~.

9.9.3

Origin of the Forlandsundet Basin: current models

The F o r l a n d s u n d e t Basin presently appears as an asymmetric 'graben-type' structure b o u n d e d by high-angle dip-slip marginal faults (Fig. 9.9). However, the origin of the basin, located within the fold-and-thrust belt of the West Spitsbergen Orogen, is problematic. Several attempts have been m a d e to explain the subsidence of the F o r l a n d s u n d e t Basin within this compressive regime, that was d o m i n a t e d by N N W - S S E strike-slip faulting ( H a r l a n d &

CENTRAL WESTERN SPITSBERGEN

9.10

Fig. 9.10. Schematic diagram of 'flower structure' within a convergent strike-slip fault zone (reproduced with permission from Lowell 1972, fig. 9). Horsfield, 1974; Harland 1979, 1985; Lepvrier & Geyssant 1984, 1985; Steel e t al. 1985; Lepvrier 1990). Harland (1979) proposed a model comprising four tectonic phases to explain the development of the Forlandsundet Basin: (1) transpression; (2) transtension; (3) minor transpression; and (4) minor transtension. The first phase of transpression resulted in the compressional deformation that caused the uplift of the West Spitsbergen Fold Belt further east; this suggests that the extensional phases occurred late in the West Spitsbergen Orogeny. Steeply dipping Palaeogene strata adjacent to the West Forlandsundet Fault in Prins Karls Forland are cited as evidence of a third minor transpressional phase. These predominantly strike-slip episodes were related to horizontal movements along the Spitsbergen Fracture Zone. The palaeostress analysis of Lepvrier & Geyssant (1985), based on faults in the Forlandsundent area suggests that four tectonic regimes can be defined: (1) extension along NW-SE-trending faults related to 'graben' formation; (2) E-W transtension (pre-Oligocene); (3) ENE-WSW compression; and (4) NNW-SSE to N-S extension. They proposed that the graben subsided as a pull-apart basin between two right-stepping dextral strike-slip faults defined by the East and West Forlandsundet faults, shortly after the main Tertiary deformation along the West Spisbergen Fold Belt. It is accepted here that some graben formation preceded the transpression phase of Harland (1979). Steel et al. (1985), in contrast to the above models, proposed that the graben formed partly during and partly after the main phase of deformation along the fold belt, with two possible models suggested. The first model proposes that the basin formed in the lee of a left-stepping restraining bend to the north of Forlandsundet; in the second model the basin is envisaged as a collapse graben in the central part of the uplifted and arched orogenic belt. Additional evidence for the development of the Forlandsundet Basin within a strike-slip regime as a pull-apart basin comes from an analysis of the sedimentary sequences. In an extensional basin the initial rifting phase is normally followed by thermal subsidence giving rise to overlapping unconformities along the basin margins. The 'flower-structure' model as proposed by Lowell (1972) for the West Spitsbergen Orogenic Belt (see Fig. 9.10) has been commonly discounted (Manby 1988; Ohta 1988; Faleide et al. 1988) but deserves reassessment (Section 9.10) in relation to the origin of the Forlandsundet Basin (Steel et al. 1985) and in this work. Kleinspehn & Teyssier (1992) assessed two new hypotheses for the origin of the Forlandsundet Basin: (1) the basin formed as the result of extension and/or transtension followed by orthogonal shortening or strike-slip deformation, and (2) the basin originated in a compressional regime, piggy-back on top of the eastward-transported thrust sheets that formed the internal part of the orogenic zone. Folding and thrusting of the basin strata occurred first (e.g. Lepvrier 1988, 1990) followed by a period of extension, probably transtension, that generated the 'graben' structure that is observed at present.

177

A tectonic interpretation of the West Spitsbergen Orogen; northern segment

The West Spitsbergen Orogen (Harland & Horsfield 1974) north of Isfjorden is the study area of this chapter. In common with the orogen south of Isfjorden, Paleocene strata (in this study area the Ny-Alesund Subgroup) were deformed by the orogeny which was demonstrably post-Paleocene with an Eocene climax (Harland 1965). The cover sequence (Carboniferous through Albian) with its varied and distinctive strata facilitated, and indeed encouraged, the many structural studies of the thrust and fold belt comprising the eastern zone of the orogen. These studies demonstrated ENEverging thin-skinned thrust and fold structures over the Nordfjorden Block utilising incompetent Triassic shale and Permian evaporites. These same d~collement layers extended over the Billefjorden Trough (e.g. Harland, M a n n & Townsend 1988; Welbon & Maher 1992) and even to the Lomfjorden Fault Zone (Andresen e t al. 1992). The northernmost segment of the orogen swings round from the general N N W - S S E trend to N W - S E trend in Broggerhalvoya with vergence trending from E N E generally to N E and then to northerly thrusting with signicant crustal shortening. The northerly component of the dextral plate suture was thus severely constrained to the north and the simple early transpressive oblique transport was resolved into E N E compression seen in the eastern fold and thrust belt and strike-slip, notably in the Forlandsundet root zone. Much less attention has been paid to the western zones of the orogen where pre-Carboniferous basement prevails. It has been argued that these basement terranes along the west coast of Spitsbergen mostly expose (Precambrian) Varanger or older strata (Harland, Hambrey & Waddams 1993). However, north of Isfjorden Early Paleozoic strata are also exposed. The Early Paleozoic and Proterozoic rocks were all deformed by the Paleogene orogeny. Moreover the Eidembreen event, dated both istopically and biostratigraphically as mid-Ordovician preceded the Bullbreen Group strata in Oscar II Land (Chapter 14). The Grampian Group strata of Prins Karls Forland may correlate approximately with the Bullbreen Group. Both groups contain conglomerate with earlier metamorphosed clasts which could result from the Eidembreen tectonism. Both groups reflect unstable conditions and may be of Late Ordovician to mid-Silurian age. There is no Devonian outcrop in the study area. The main body of Svalbard to the east suffered major Silurian and minor Devonian tectonism, typical of the Caledonides: but so far no decisive evidence has been forthcoming for significant Silurian tectonism. Indeed it would be surprising if there were, because at this time the location of this terrane was probably nearer to that of Pearya in northern Ellesmere Island and far from the Iapetus-Caledonian developments. This accounts for the difficulty in distinguishing a Caledonian event in the detailed study by Morris (1989). This palinspastic arrangement is only part of the hypothesis of Harland & Wright (1979) that makes Svalbard a composite terrrane with this western province being joined by the central and eastern provinces by Silurian and Devonian sinistral strike-slip. The postulated Kongsfjorden-Hansbreen Fault Zone along which this docking took place is obscured by the later Carboniferous sedimentation and the Paleogene orogeny. However, such a fundamental fault may well have located the boundary between the Nordfjorden Block and the St Jonsfjorden Trough and also the subsequent boundary within the West Spitsbergen Orogen between the thrust and fold belt with its thin-skinned structures to the east and the deeper deformation to the west. The above hypothesis is retailed at this point to take account of some enigmatic problems discussed in the three foregoing sections. (a) In Oscar II Land Ratliff, Morris & Dodt (1988), in analysing the structure of the Bullbreen Group, argue for a N W - S E dextral shear zone with E N E verging thrust folds and not easily distinguished from the E N E verging Paleogene structures. Their argument that the structures were pre-Carboniferous is tenuous and, if mistaken, this structure is probably an integral part of the

178

CHAPTER 9

Paleogene orogeny with which the dextral transpression is consistent. Morris (1988) suggested that the later deformation involved northward, followed by easterly, directed thrusting. Thus two Paleogene phases may be distinguished here. (b) In Prins Karls Forland Manby (1986) could not in the end distinguish clearly between his D 1 and D2. He was expecting D 1 to be Caledonian and D2 to be Tertiary. In so far as some D1 structures deform Grampian Group strata it is possible that they should be D2 in his terminology. This would leave D1 for the schistosity and other fabrics in the Scotia and other earlier Groups that occur as pebbles in the Sutor Conglomerate. Making this assumption then the conspicuous D2 structures all verge to the SSW. (c) The Forlandsundet structure is no superficial graben. It has a complex history, with not only relatively porous and coal-beating strata in the later Balanuspynten Formation, but indurated vertical sandstones not easily distinguished from the subjacent Grampian Group strata in the northern cliff section of Prins Karls Forland. This would suggest that pre-orogenic as well as syn- and postorogenic Paleogene strata are preserved. (d) Putting these possibilities together, the model for the West Spitsbergen Orogen proposed by Lowell (1972) may again be considered with an axial-root zone for the orogen with WSW verging structures in Prins Karls Forland and ENE verging structures in eastern Oscar II Land. He also adopted the transpression hypothesis (Harland 1971) (Fig. 9.10) which is consistent with the plate-tectonic motions at that time. This model is consistent with the deep dextral Kaffioyra and Sarsoyra shear zone elucidated by Ohta et al. (1995).

On this basis a NNE-SSW dextral fault zone occupied Forlandsundet. (1) Paleocene transtension would have allowed deposition in a pull-apart basin. (2) During the main orogeny extreme transpression would have generated the steep thrusts along the axis, now mostly covered by water and late Paleogene strata, and pushed the strata outwards on each side to the ENE and WSW. (3) Late orogenic (Late Eocene) strike-slip continued with transtension and the development of the main pull-apart basin. In such a dynamic situation local and/or short term transpression complicated the depositional story. (4) The main dextral strike-slip may have continued without transpression or transtension into Neogene time. It might account for the large low flat area of Prins Karls Forland if it had been opposite Isfjorden when it was a wide valley. This speculation is an optional extra. However, the main dextral strike-slip was entirely taken up in faults west of Prins Karls Forland. The location of this Forlandsundet axis of the Orogen need be no surprise because of the location of the intense sinistral shearing of Vendian strata seen both in western Oscar II Land at Daudmannsodden, and in eastern Prins Karls Forland in the deformation of the tillite stones. That could have been part of the Eidembreen event but a Devonian age is preferred here. It is a fundamental fault zone with a long history. It fits the 'Tertiary orogen-parallel motion in the crystalline hinterland of Spitsbergen's fold-thrust belt' of Maher et al. (1997).

Chapter 10 Southwestern and Southern Spitsbergen W. B R I A N 10.1 10.1.1 10.1.2 10.2 10.2.1 10.2.2 10.3

HARLAND

with contributions with PAUL

Paleogene strata, 180

10.7.1

Calypsostranda Basin, 180 Oyrlandet Basin, 180

10.7.2 10.7.3

A. D O U B L E D A Y

Mesozoic strata in southwest Sarkapp Land, 182

Adventdalen Group, 182 Kapp Toscana and Sassendalen groups, 182 Permian and Carboniferous strata of southern Spitsbergen,

(W.B.H. & I.G.) 183 10.3.1 Kapp Starostin Formation (Tempelfjorden Group), 184 10.3.2 Tokrossoya Formation (Tempelfjorden Group), 184 10.3.3 Treskelodden (Reinodden) Formation (Treskelen Subgroup, Gipsdalen Group), 184 10.3.4 Hyrnefjellet Formation (Treskelen Subgroup, Gipsdalen Group), 186 10.3.5 Sergeijevfjellet Formation (Billefjorden Group), 186 10.3.6 Hornsundneset Formation (Billefjorden Group), 187 10.3.7 Adriabukta Formation (Billefjorden Group), 187 10.4 Devonian strata, 187 10.5 Proterozoic strata of western Nordenskiiild Land, 188 10.5.1 Sequence of the rock units, 188 10.5.2 Mineralization, 189 10.6 Proterozoic strata of western Nathorst and northwestern Wedel

10.7.4 10.8 10.8.1 10.8.2 10.8.3 10.9 10.10 10.10.1 10.10.2 10.11 10.12

& ISOBEL GEDDES

West of Hansbreen, 192 Early Paleozoic and Proterozoic strata east of Hansbreen, 194 Comparison of stratal schemes for southwest Wedel Jarlsberg Land, 195 Mineralization, 197 Early Paleozoic and Proterozoic strata of Sorkapp Land, 197

Early Paleozoic strata, 197 Neoproterozoic strata, 198 Mineralization around Andvika, 199 Correlation of pre-Devonian through southwest Spitsbergen, 199 Structure of western Nordenskiiild Land, 200

Eastern margin of the fold belt, 200 Main fold belt, 201 Structure of western Natborst Land, 201 Structure of Wedel Jarlsberg Land (W.B.H. & P.A.D.), 201

Neoproterozoic succession of northwestern Wedel Jarlsberg Land, 189 10.6.2 Proterozoic basement, 191 10.7 Early Paleozoic and Proterozoic strata of southwestern Wedel Jarlsberg Land, 191

10.12.1 10.12.2 10.12.3 10.12.4 10.12.5 10.12.6 10.13 10.13.1 10.13.2 10.13.3 10.13.4 10.13.5

This chapter treats that part of the West Spitsbergen Orogen south of Isfjorden (Figs 10.1, 10.2, 10.3). It follows the same pattern as the last in treating the stratigraphy of the area, then the structure. Southwestern differs from central western Spitsbergen in being of greater length, more stratigraphic variety but less pronounced Cenozoic deformation. This appears to decrease in intensity southwards. There is, moreover, a conspicuous contrast south of Isfjorden from a fold belt with many thrusts to one with less evident crustal shortening south of it. This correlates with the Central Basin to the east. The younger rocks vary in facies gradually enough to be treated together. They are, in effect, the western margin of the Central Basin the subject of Chapter 4. They are admirably described in the standard section for Svalbard at Festningen at the northern limit of the area, where the rocks of the cover sequence were overfolded and overthrust at the western limit of the basin in the West Spitsbergen Orogeny. They are seen well exposed in vertical strata in almost uninterrupted sequence. Of the younger rocks only the Calypsostranda Group is described briefly in Section 10.1 and the Oyrlandet Basin in Section 10.2 as they are isolated outcrops in the west. The Cretaceous and Jurassic strata are treated entirely in Chapters 4 and 5 and have no detail here. The Triassic strata may also be seen as an extension of the Central Basin and are so described in Chapter 4. However, the structural peculiarity in the south is worth noting again in this regional context and so has a small section (10.2). The Permian and Carboniferous strata extending beyond the Central Basin are described in Section 10.3. The small outcrops of Devonian strata in the south are described briefly in Section 10.4. The older rocks (pre-Devonian) have suffered three or more major tectonic episodes in Proterozoic, Paleozoic and Cenozoic time and it is often not easy to distinguish these in so far as the latest two, at least in the south, were both overthrust eastwards. The older rocks are also difficult to correlate and have received distinct nomenclature for each of four areas. The difficulty in correlation stems from differences of opinion. To avoid introducing

controversial assumptions at the initial descriptive stage in this investigation further nomenclature was introduced and has been followed to complete the independence of each descriptive area of strata between the areas and so to facilitate discussion of correlation at the end of the chapter. The differences of opinion on correlation present a problem for description of strata. It so happens that, especially in the southwest of the area (southwestern Wedel Jarlsberg Land and Sorkapp Land) the Polish group under the leadership of K. Birkenmajer have done the lion's share of the work and the early scheme established about 1960 has been continued and refined by that group. It has also been largely adopted by Norwegian, Russian and American groups. Therefore the initial description of strata will follow that scheme. However, the Cambridge group working independently and extending their correlation anticlockwise from the northeast of Svalbard came to different conclusions on reaching southwest Spitsbergen. Their interpretations were based in part on the opinion that in pre-Carboniferous time the different once distant terranes could lead to different correlations. Other work has also diverged. Therefore, alternative stratigraphic schemes have been formulated to challenge and modify the established scheme. Discussion of this challenge follows the descriptive sections which are arranged in areas to facilitate comparisons. Discussion of the West Spitsbergen Orogeny fold belt is similarly divided by Van Mijenfjorden, Van Keulenfjorden and Hornsund physically into four a r e a s - namely Nordenski61d Land, Western Nathorst Land, Wedel Jarlsberg Land, and Sorkapp Land. A distinctive feature of this sector of Spitsbergen is the occurrence of metallic sulphide minerals. They have been long known but only since about 1950 have they been considered systematically (e.g. Hjelle 1962; Birkenmajer & Wojciechowski 1964; Flood 1969; Czerny, Plywacz & Szubala 1992; Cerny, Kieres & Manecki 1992). With few exceptions they occur within Precambrian and entirely within pre-Devonian strata (Chapter 3.6.3). The only other economic exploration which resulted in a very limited coal mine was in the late Paleogene strata of Calypsobyen.

Jarlsberg lands, 189

10.6.1

Structure of the West Spitsbergen Orogen, 201 Postulated Silurian-Devonian strike-slip faulting, 204 Caledonian structures, 204 Jarlsbergian diastrophism, 204 Proto-basement deformation, 205 Post-proto-basement deformation of Precambrian rocks, 205 Structure of Surkapp Land (W.B.H. & P.A.D.), 205

The structural units, 205 Proterozoic structures, 205 Paleozoic structures, 206 Mesozoic structures, 207 Paleogene structures, 207

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CHAPTER 10

Key to numbered localities 1 2 3 4 5 6 7 8 9 10 11 12

Adriabukta 13 Barentsburg 14 Bredichinryggen 15 Brepollen 16 Burgerbukta 17 Calypsostranda 18 Elveflya 19 Fannypynten 20 Fridtjovhamna 21 G&shamna 22 Hansvika 23 Hyrne~ellet 24

Isbjornhamna KappMineral Konglomeratfjellet L~gnesbukta Linn60ella Linnevatnet Luciakammen Magnethogda Nottinghambukta Paske~ella Pulkovafjella Recherche~orden

25 26 27 28 29 30 31 32 33 34 35

Revdalen Rochesterpynten Samarinbreen Slyngfjellet Sofiekammen Treskelen Tsjerbysjovfjellet Van Muydenbukta Vimsodden Vrangpeisbreen Werenski61dbreen

Fig. 10.1. Topographic and place name map for Isfjorden to Sorkapp, based on Topographical Map o f Savlbard 1:500 000, sheet 1, Norsk Polarinstitutt.

10.1

Paleogene strata

T h e Paleogene strata belonging to the Central Basin, which b o u n d this study area to the east are treated in C h a p t e r 4. However, there is a faulted outlier, possibly a half-graben, on the coastline near K a p p Lyell. A n a l o g o u s to the F o r l a n d s u n d e t Graben, its stratig r a p h y is quite distinct f r o m that of the Central Basin. A n o t h e r possible half-graben is at Oyrlandet.

I0.I.I

Calypsostranda Basin

Calypsostranda Group (SKS 1995) comprises for the Tertiary strata of Renardodden (Thiedig et al. 1980) near Kap Lyell. Renardodden Fm (Thiedig et al. 1980) >217m. Mainly sandstone with occasional pebbles and coal fragments, some beds with ferruginous concretions. A basal conglomerate which rests on the Skilvika Fm. Skilvika Fm (Livshits 1967; Thiedig et al. 1980) 115.5 m. Mainly siltstones with some shales, thin sandstone beds and coals, also with coal pebbles, plant beds and a basal conglomerate which rests unconformably on the Rochesterpynten Fm. The age of the Renardodden and Skilvika formations had been determined as Oligocene by Livshits (1974) on the bases of pollen and spores and by Head (1984) and Manum & Throndsen (1986) as Late Eocene-Early Oligocene on the basis of dinocysts. Rochesterpynten Fm (Harland, Hambrey & Waddams 1993, p. 100). The description of this unit by Pickton & Harland in 1975 was inadvertently omitted from Thiedig et al. (1980). It comprises a tectono-sedimentary melange, formed largely of derived meta-diamictite blocks from the Kapp Lyell Group some of which are some metres across, probably resulting from collapse and slumping at an active fault scarp. There was possibly some induration event before deposition of the Skilvika Formation. These rocks were also described by Dallmann (1989). He extended an Inner Hornsund Fault Zone through Recherchebreen to make the Calypsostranda graben structure. He also noted the constituents of boulder conglomerates consolidated prior to 'Caledonian' metamorphism. He observed the effects of weathering of these blocks prior to the red-weathering and overlying sandstone horizon.

10.1.2

Oyrlandet Basin

O y r l a n d e t is the lower g r o u n d in s o u t h w e s t e r n m o s t Sorkapp L a n d west of the H o r n s u n d H i g h (e.g. Kistefjellet) at that latitude a n d east of the western fold zone of the West Spitsbergen Orogen at Oyrlandsodden. The only p r e - Q u a t e r n a r y rocks are tiny inliers of Paleogene strata towards the south and Cretaceous strata towards the n o r t h a n d also Paleogene coastal sections on the east side of Sommerfeldtbukta.

SOUTHWESTERN AND SOUTHERN SPITSBERGEN

181

Fig. 10.2. Generalized outcrop map of central and southwestern Spitsbergen, based on Harland, Hambrey & Waddams (1993), and Geological Map of Svalbard 1:100 000 sheets B9, B10, B11, B12 and C13. KHFZ, Kongsfjorden-Hansbreen Fault Zone. The Paleogene strata were regarded by Atkinson (1963) as an extension of the Central Basin. They are however separated structurally by the Hornsund High though Paleogene strata may once have extended throughout the area. It is now a distinct small basin bounded to the southwest by Tempelfjorden Group strata and to the east by a fault so it may be regarded as a half graben or graben. It is based on the diagrammatic map in Dallmann et al. (1993) as the Oyrlandet Graben. The fullest account is by Dallmann et al. (1993) who reported that whereas the Firkanten (Barentsberg) Formation is c. 140150 m thick to the east it may reach 300 m in the Graben. The most complete exposures appear against the eastern fault of the graben on the east coast of Sommerfeldtbukta. It is divided into three members, which are also recognizable in the outcrops to the east, following Kalgraff in Steel et al. (1981). Firkanten Fm ?c. 300. Endalen Mbr, 200+m comprises immature, light grey, porous fine- to medium-grained sandstone with coaly flakes and flazer bedding. Dark grey quartzitic sandstones and silty shales are interbedded. Kolthoffberget Mbr, c. 20+m of black or dark grey silty shales with brownish red-weathering colours and spheroidal cleavage. It weathers characteristically into small steep incised valleys only a few metres deep. Todalen Mbr, c. 30m of bioturbated, occasionally ripple-marked finegrained sandstones with plant remains and occasional coal seams. There is a (?basal) gravel conglomerate.

182

CHAPTER 10

Fig. 10.3. Simplified tectonic map of central and southwestern Spitsbergen.

10.2

Mesozoic strata in southwest Sorkapp Land

The Mesozoic stratigraphy of Svalbard is very largely treated in Chapters 4 and 5 so that the western margin of the Central Basin practically defines the artificial division between Chapters 4 and 10.

10.2.1

Adventdalen Group

The Adventdalen Group (Cretaceous-Jurassic) strata extend in a SSE direction within the main (eastern) fold and thrust belt of the West Spitsbergen Orogen. This reaches the southern shore of Sorkapp Land east of Mathiasbreen and, in effect east of the Hornsund High (see below). On the Hornsund High, at Kistefjellet, Janusffjellet Subgroup strata rest at the summit on Triassic strata which rest directly on folded Precambrian rocks. Further west and occupying low ground corresponding to Sommerfeldtbukta is the Oydandet plain just above sea level and exposing only small patches of pre-Quaternary strata. These include the Oyrlandet Paleogene and some exposures of the Cretaceous Helvetiafjellet Formation. Whether the basin contains a fuller Mesozoic succession is uncertain.

10.2.2

Kapp Toscana and Sassendalen groups

The Kapp Toscana and Sassendalen groups have been described generally in Chapters 4 and 5 as there is sufficient uniformity o f facies throughout the outcrop area in Spitsbergen for the strata most conveniently to be treated together as in Chapter 4. This southwestern sector of Spitsbergen contains contrasting successions between northern and southern Triassic outcrops.

(a) The northern outcrops. From Nordenski61d Land to northern Wedel Jarlsberg Land are exposed the thickest Triassic developments in Svalbard. Their extension to the west has been lost to erosion after the Paleogene folding and uplift. The succession from the Festningen coastline to southern Nordenskirld Land, Nathorst Land and Western Wedel Jarlsberg Land is relatively uniform and is summarized here.

Kapp Toscana Gp Wilhelmoya Fm. The overlying 'Lias' conglomerate (Brentskardhaugen Bed), taken in this work as the base of the Janusfjellet Subgroup of the Adventdalen Group, extends throughout this sector, the underlying Wilhelmoya Fm is generally about 5 to t0m in the northrn development but may thicken in the southern succession to about 25 m and up to 75 m (Worsley & Mork 1978).

SOUTHWESTERN AND SOUTHERN SPITSBERGEN

De Geerdalen Fm. This typical sandstone facies forms the bulk of the main northern development reaching a thickness of 327 m at Festningen and about 200 m at Van Keulenfjorden. Tschermakfjellet Fin. Whereas this distinctive marine facies is established as a formation it is not noticeable in this northern thicker development but develops in the south up to about 25 m (Worsley & Mork 1978). Sassendalen Gp Botneheia Fro, 210 m (thinning south to 8 cm at Kistefjellet). It is from this section at Bravaisberget (in SW Nathorst Land) that Mork, Knarud & Worsley (1982) renamed the Botneheia Fm (Birkenmajer 1977). Worsley & Mork (1978) divided the formation into two members. Somnovbreen Mbr is coarser grained in which silstones dominate shales. Passhatten Mbr is typical of the Botneheia Fm in the Central Basin with soft black, often bituminous shales with thin siltstone interbeds containing phosphatic nodules. Sticky Keep Fro, 220m up to 278m at Bravaisberget and thinning southwards to 110m. Similarly from the section at Festningen, at the southern entrance to Isfjorden, Mork, Knarud & Worsley (1982) renamed the Sticky Keep Fm at Tvillingodden where it also crops out. It is typically a coarsening-upward unit of siltstones and sandstones with shales. In Bellsund brachiopod-bearing limestones (the Retzia Limestone of Lundgren, 1887) are well known and occur near the base of the formation, possibly correlating biostratigraphically with beds in the underlying formation but occurring in the basal shales of the Sticky Keep Fm. Vardebukta Fm, 290 m thinning southward to 70 m. This formation also becomes coarser near the top where sandstones contrast with the overlying shales. At the bottom the top shales may rest on the resistant Kapp Starostin Fm and are typically obscured. The upper sandstones are cross-bedded, often with carbonate cement and with infilled burrows. In the south two members were proposed (Birkenmajer 1977) which may be the equivalent of the lower (Selmaneset) Member established at Isfjorden (Buchan et al. 1965).

(b) The southern outcrops. The s o u t h e r n outcrops f r o m s o u t h e r n W e d e l Jarlsberg L a n d s o u t h w a r d s are distributed over a complex structural terrane in w h i c h four zones f r o m east to west have been recognized. Thicknesses reduce to less t h a n h a l f that at Festningen. (i) The southern extension of the foldbelt. In the east the familiar stratigraphical relationships within the fold belt c o n t i n u e southwards. (ii) T h e Hornsund H i g h is distinguished by relatively flattying Triassic strata resting u n c o n f o r m a b l y on, a n d truncating, d e f o r m e d P r e c a m b r i a n a n d Early Paleozoic strata. T h e earliest Triassic strata are Dienerian a n d the reduced V a r d e b u k t a a n d Sticky K e e p f o r m a t i o n s are distinguishable, b u t n o t so easily. Therefore M o r k , K n a r u d & Worstey (1982) i n t r o d u c e d the n a m e Kistefjellet F o r m a t i o n to c o m b i n e these two units a n d c o n t i n u e d the easily recognisable B o t n e h e i a F o r m a t i o n using their n a m e (Bravaisberget) for the f o r m a t i o n . In s u m m a r y the succession in zone (ii) is:

Kapp Toscana Gp. As indicated in the northern part of this sector where the De Geerdalen Formation comprises almost the whole of the Group in its thicker development these southern successions contain significant thicknesses of all three formations for example at Treskelen in Hornsund and Kistefjellet in southern Sorkapp Land thicknesses respectively are (Worsley & Mork 1978) Willkelmoya Fm, 20 m and 35 m De Geerdalen Fin, t 15 m and 30 m Tschermakfjellet Fin, 250m and 12m Sassendalen Gp Botneheia Fm is an upward-coarsening sequence divided into three members. Somnovbreen Mbr of fine bioturbated sandstones with carbonate cements. Karentopgen Mbr develops locally (up to 43 m) is of coarse-gained planar cross-bedded sandstones, with conglomerates and large channel-fill structures which indicate sediment transport to the east and southeast. Passhatten Mbr is of dark shales with the characteristic phosphatic nodules of the Botneheia Fm with middle Triassic fossils. Kistefjellet Fin, 38 m. This formation combined the Upper Vardebukta and the Sticky Keep fms in this new name by Mork et al. (1982). Mork & Worsley (1979) had redefined the Brevassfjeltet conglomerate of Birkenmajer (1977) which corresponded approximately to the Vardebukta Fm as below.

183

The main body of the formation is of interbedded fossiliferous shales and medium to very fine sandstones which may contain ripples or carbonate cement. This would correspond to the Sticky Keep Fm. The Vardebukta unit is distinguished by conglomerate beds at the top and base. At the top is the Urnetoppen (conglomerate) Mbr and at the base is the Brevassfjdlet (conglomerate) Mbr. This is a basal conglomerate resting on deformed and truncated Precambrian and Early Paleozoic strata on the Hornsund High. It extends to the west, zone (iii), where it rests on Carboniferous strata. Its age is Dienerian to Spathian or even early Anisian (Mork & Worsley 1979). (iii) West of the H o r n s u n d High, a n d west o f the s o u t h e r n extension o f the H a n s b r e e n F a u l t Z o n e is a wide o u t c r o p of C a r b o n i f e r o u s strata, m a i n l y sandstone, which are relatively fiat-lying. O n these rest the Brevassfjellet c o n g l o m e r a t e s with little obvious discordance. H o w e v e r , the w h o l e o f zones (i) to (iv) have suffered Paleogene tectonism and whereas in zone (i) the Triassic overlie Permian, C a r b o n i f e r o u s a n d D e v o n i a n strata a n d are infolded with them, in zone (ii) they have suffered only relatively horizontal bedding thrusts which are still m o r e obvious in zone (iii). (iv) S o r k a p p o y a a n d T o k r o s s o y a are islands to the SSE o f O y r l a n d s o d d e n the s o u t h e r n m o s t tip o f Spitsbergen w h e r e the Triassic strata are steeply infolded with a p p r o x i m a t e l y c o n c o r d a n t K a p p Starostin F o r m a t i o n strata. T h e strike of these structures, extended n o r t h w a r d s , passes in a N N W - S S E direction t h r o u g h T o k r o s s o y a , O y r l a n d s o d d e n tangentially offshore to the rest o f S o r k a p p L a n d a n d Wedel Jarlsberg L a n d a n d so represents a western fold belt in the West Spitsbergen Orogen. Just to the northeast o f this foldbelt is the small g r a b e n basin of O y r l a n d e t already referred to above.

10.3

P e r m i a n and Carboniferous strata o f southern Spitsbergen

In s o u t h e r n Spitsbergen Late Paleozoic strata occur within the Tertiary fold-and-thrust belt. T h e y are exposed in a thin bett trending N N W - S S E f r o m Akseloya across the western tip o f N a t h o r s t L a n d , across eastern Wedel Jarlsberg L a n d into central S o r k a p p L a n d . Exposures also occur in a separate, small, belt at the s o u t h w e s t e r n tip o f S o r k a p p L a n d a n d extend across to Sorkappoya. T h e C a r b o n i f e r o u s evolution o f the region was c o n t r o l l e d by the presence o f t w o b a s e m e n t highs: the W e d e l Jarlsberg L a n d H i g h a n d the S o r k a p p - H o r n s u n d High. O n the n o r t h side o f the f o r m e r lay the St J o n s f j o r d e n T r o u g h extending f r o m O s c a r II L a n d into Nordenski61d L a n d a n d N a t h o r s t L a n d . H e n c e the rocks in those areas share C a r b o n i f e r o u s stratigraphic n o m e n clature a n d are all described in C h a p t e r 9. Between the two b a s e m e n t highs lay the I n n e r H o r n s u n d T r o u g h , c o n t a i n i n g m o s t o f the rocks described in this section. S o u t h o f the S o r k a p p H o m s u n d H i g h there p r o b a b l y lay a n o t h e r basin, but the resultant sediments are n o t well exposed or described. P e r m i a n rocks b l a n k e t e d the region including the highs, such that the K a p p Starostin F o r m a t i o n can be traced into the area. H o w e v e r , it is n a m e d s o u t h o f the H o r n s u n d H i g h as the T o k r o s s o y a Formation. As elsewhere in Svalbard, the rocks fall into the three groups, as follows.

lh?msow Land Supergp Tempelfjorden Gp Kapp Starostin Fin (correlated with the) Tokrossoya Fm Gipsdalen Gp Treskelen Subgp Treskdodden Fin HyrnefjeHet Fin

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CHAPTER 10

Billefjorden Gp Sergeijevfjellet Fm Hornsundneset Fm Adriabukta Fm E a c h is described below.

10.3.1

Kapp Starostin Formation (Tempelfjorden Group)

T h e K a p p S t a r o s t i n F o r m a t i o n (defined in C h a p t e r 4) is best d e v e l o p e d in n o r t h e r n a n d central Spitsbergen, as it thins a n d d i s a p p e a r s s o u t h w a r d s in S o r k a p p L a n d . H o w e v e r , it did f o r m o n the W e d e l Jarlsberg L a n d High, e x t e n d into the I n n e r H o r n s u n d T r o u g h a n d o n to the H o r n s u n d H i g h , s o u t h w e s t o f w h i c h it was named Tokrossoya Formation. From Nathorst Land (Midterhuken) the Kapp Starostin Fm thins from 385 m to 150 m at Zittelberget in Wedel Jarlsberg Land/Torell Land. There, the three main divisions of the formation can be recognized (Dallmann e t al., B11G, 1990) as follows. The upper Hovtinden Mbr, 80-215m of chertified siltstones and very finegrained sandstones with glauconite, as well as pure spiculitic cherts. The Svenskeegga Mbr, 60-160m contains sandy, sparry limestone with abundant fossil remains, interbedded with some sandstones, rounded quartz and chert-pebble conglomerates and pure chert layers. Some of the limestones show cross-bedding which indicates a variety of current directions. There is also a thin lignite horizon interbedded with the limestones at one locality. The lowermost Voringen Mbr is barely distinguishable, containing only 6-12 m in the north of calcitic fossiliferous packstone. In northern Wedel Jarlsberg Land the sections at Reinodden were described with biostratigraphic detail by Nakazawa et al. (1990). In particular the three members of the Kapp Starostin were characterised in successive beds. Of most interest is their uppermost fossil records from the Hovtinden Member which they correlate with the Chinese sequence where late Permian biotas are better represented and argue Late Leonardian and Early Roadian ages (Ufimian into Wordian). This leaves Capitanian and Lopingian time not recorded. Southwards, the lower two of the three members appears to die out towards the Hornsund High, with a notable decrease in thickness. At Treskelodden (Hornsund), the uppermost Hovtinden Mbr lies directly on the Treskelodden Fm, cutting out the entire Gipshuken Fm. Calcareous siltstones are underlain by basal conglomerates which were deposited on different units of the Treskelodden Fm and infill karst surfaces in the limestones. About 12km further south, the Kapp Starostin Fm is even thinner, only 5.5m at Austjokeltinden. There, fossiliferous, glauconitic, calcareous siltstones, sandstones and limestones occur, with repeated conglomerates and lags containing abraded phosphatic steinkerns, lie on the Treskelodden Fro. There appears to be only one possible explanation to the generalization that in Wedel Jarlsberg Land west of Recherchebreen, Paleozoic through Mesozoic strata are not recorded. The exception would be the blocks of Kapp Starostin facies inland of Calypsobyen near the snout of Scottbreen (Kowallis & Craddock 1982). These are few and limited to a small area, but flat-lying and not tectonized. If they are not erratics they might suggest (i) that mid-Permian rested unconformably on Vendian strata and (ii) that the deformation evident in the Kapp Lyell strata was earlier. Neither conclusion can be certain because the Kapp Starostin Formation is remarkably strong.

10.3.2

Tokrossoya Formation (Tempelfjorden Group)

In s o u t h w e s t e r n S o r k a p p L a n d this f o r m a t i o n c o n t i n u e s the K a p p S t a r o s t i n F o r m a t i o n , w i t h w h i c h it has m a n y similarities. It is at least 400 m thick, a l t h o u g h the base a n d t o p are n o t seen. It consists o f cherts, limestones a n d arenites with an a b u n d a n t f a u n a w h i c h indicates a K u n g u r i a n - W o r d i a n age. It coarsens u p w a r d s overall, a n d was p r o b a b l y d e p o s i t e d in a m a r g i n a l m a r i n e e n v i r o n m e n t . This formation, first described by Siedlecki (1964), consists of sandstone, limestone and chert which occurs in the extreme southwest of Sorkapp Land and on the offshore islands. It was the lateral equivalent of the Kapp

Starostin Fm, preserved in a separate basin southwest of the Hornsund High. It is included as a member within the Kapp Starostin Formation by some authors; for example in the map of Sorkapp (Dallmann et al., CI3G, 1993; Winsnes et al. 1993). The formation consists of about 50% cherts, 30% limestones and 20% arenites of essentially the same lithologies as the Kapp Starostin Fm (see above). Two divisions have been recognized. Fossils are plentiful, but few have been described specifically from this formation. Malecki (1968) described bryozoans, and brachiopods also occur. The fauna correlates with the Kapp Starostin Fm (Malecki 1968). In the earlier description (Siedlecki 1964) the sequence was thought to be the other way up, so Siedlecki's Upper Tokrossoya Beds are equivalent to the Lower Mbr described here. Upper Mbr. This consists of over 200 m of interbedded limestones and arenites containing an abundant, but rather restricted fauna of productids and spiriferids, with two distinct bryozoan horizons. Lower Mbr. This is relatively poorly fossiliferous and consists of 200 m of massive, dark-coloured cherts which are resistant to weathering. On purely lithological grounds, the more arencaceous Upper Mbr may correlate with the Hovtinden Mbr and be of Late Ufimian-Wordian age. The Lower Mbr would then correlate with the Svenskeegga and Voringen mbrs and be of Kungurian-Ufimian age.

10.3.3

Treskelodden (Reinodden) Formation (Treskelen Subgroup, Gipsdalen Group)

T h e T r e s k e l o d d e n F o r m a t i o n was defined in the H o r n s u n d n e s e t area, a n d its equivalent, the R e i n o d d e n F o r m a t i o n was described f r o m Bellsund. S K S ( D a l l m a n n e t al. 1996) has ruled t h a t the T r e s k e l o d d e n F o r m a t i o n , h a v i n g priority ( B i r k e n m a j e r 1959) s h o u l d apply to b o t h . T h e rocks at R e i n o d d e n were described as n a m e d by Orvin (1940) a n d b o t h units were described as n a m e d f o r m a t i o n s by Cutbill & C h a l l i n o r (1965) a n d N y s a e t h e r (1977). It c o n t a i n s cyclic sequences o f yellow, red or b r o w n s a n d s t o n e c o m m o n l y c r o s s - b e d d e d , c o n g l o m e r a t e with q u a r t z a n d chert clasts, limestone sparry or sandy, a n d d o l o s t o n e , c o m m o n l y with p l a n t f r a g m e n t s a n d desiccation cracks at the top. Lateral facies v a r i a t i o n is a characteristic o f the unit, with s a n d s t o n e s c h a n g i n g laterally into l i m e s t o n e or c o n g l o m e r a t e which f o r m only a small b u t significant p r o p o r t i o n o f the total, increasing in i m p o r t a n c e to the south. T h e f o r m a t i o n shows evidence o f d e p o s i t i o n in b o t h m a r i n e a n d terrestrial settings, p r o b a b l y in a n alluvial system at the base a n d a fan delta for the r e m a i n d e r . Tidal channel, intertidal, offshore bar a n d l a g o o n a l facies are all represented. There was an increasing m a r i n e influence u p w a r d s t h r o u g h the f o r m a t i o n . T h e limestones c o n t a i n an a b u n d a n t f a u n a , a l t h o u g h the age is n o t tightly defined. It is p r o b a b l y Late C a r b o n i f e r o u s (Gzelian) to Early P e r m i a n ( A s s e l i a n - S a k m a r i a n ) . (a) Hornsund. The Treskelodden Fm consists of rhythmically deposited sandstones, conglomerates, limestones and dolomites. There is rapid facies variation from west to the east which is complicated by overthrusting during Tertiary deformation. The lower 20-50m appear to be unfossiliferous, in contrast to higher levels which are rich in fossils, notably corals. Nysaether (1977) attempted a litho-correlation of the lower unit of his 'Drevbreen beds' with the upper Treskelodden Fm which he considered is their partial lateral equivalent and downward continuation. He correlated the latter lithostratigraphically with his Reinodden Fm. The type section is at Treskelodden, Hornsund, where the sequence is 129 m. The formation has a limited outcrop, largely confined to inner Hornsund, although some outcrops occur inland; in west-central Torell Land it is 185 m at Polakkfjellet where the top of the formation can be seen. It appears to thin rapidly onto the Hornsund High and is only 50 m at Kopernikusfjellet and 70 m at Urnetoppen. South of Hornsund, 280 m of coarse clastics at Bautaen possibly belong to the Treskelodden Fm and the formation appears again further south at Ausjokeltinden where 125 m are exposed (Hellem & Worsley 1978). To the east it is obscured by younger strata and northwards it seems likely that this facies is replaced by carbonate of the Tyrrellfjellet Mbr (Wordiekammen Fm). The upper boundary is the unconformity below the siliceous Hovtinden Mbr of the Kapp Starostin Fm. In the Hornsund area, the Hovtinden Mbr is cut out westward by the Triassic unconformity and locally Triassic shales rest on the Treskelodden Fm. There is evidence of erosion on the top surface

SOUTHWESTERN A N D SOUTHERN SPITSBERGEN of the uppermost beds. However, at Polakkfjellet the top can be seen to be conformable beneath the Gipshuken Fm which has not been eroded here (Birkenmajer 1977, fig. 15). According to Birkenmajer (1984), the lower boundary is unconformable on the red conglomerates and sandstone of the Hyrnefjellet Fro, which is probably of Carboniferous age. Prior to Birkenmajer's detailed account, the lower boundary was considered to be transitional to the Hyrnefjellet Fm, which, except for the colour, is lithologically similar to the lower Treskelodden Fm. Sandstones make up the bulk of the formation (60%). They are commonly calcareous, and in the upper part are closely interbedded with, and pass laterally into, limestones. They are hard, compact, and generally well-sorted, but conglomeratic lenses and layers are common. Large colonial and solitary corals are present. Cement is usually calcite or quartz. In the lower part sandstones pass westwards into conglomerates. There are some ferruginous horizons. South of Hornsund, the sandstones become increasingly conglomeratic and they pass into conglomerates, which make up about 10% of the whole formation. Thin bands of extremely heterogeneous, poorly rounded and sorted conglomerate contain pre-Devonian and possibly Early Carboniferous pebbles. The conglomerate of the lower part of the formation consists of quartz and pre-Devonian pebbles with fair sorting and rounding. In the structural unit south of Hornsund, over 200m of texturally mature, grain-supported, massive quartz conglomerate occurs. Its base is not seen and it is overlain by Early Triassic rocks, (possibly overthrust), so its relationship to the rest of the Permian sequence is not known. Gjelberg & Steel (1981) described it as the 'Bladegga conglomerate', underlying the Hyrnefjellet Fm and considered it to belong to the Carboniferous sequence. Further south still, at Austjokeltinden in Sorkapp Land, 125m of Treskelodden F m are exposed beneath the Kapp Starostin Fm, consisting of conglomerates, sandstones and minor shales. A fossiliferous horizon here is the uppermost shale, which contains corals (Hellem & Worsley 1978). The fossiliferous limestones constitute 25% of the formation and appear in the upper part as thin interbeds in the predominantly arenaceous sequence. They contain large coral colonies, solitary corals and brachiopods. At the top of the formation a thicker limestone occurs. The limestones are generally grey calcarenites and biocalcarenites, and may grade into calcareous sandstone. There are some horizons of dolomite and thin red shale. The rocks are arranged in predominantly upward-fining cycles on both a large and small scale, described in detail by Birkenmajer. Fossiliferous (coral-bearing) conglomerates and biogenic limestone are generally confined to the base of the cycles. They usually show sharply delimited erosional bases and commonly begin as channels cutting into the top part of the preceding cycle. The middle part of the cycle is dominated by calcareous sandstone and quartzite, with large-scale planar cross-bedding and subordinate conglomerates. The tops of many cycles are characterized by fine sediments with plant fragments and desiccation cracks. This part of the cycle is commonly missing in many cases due to intraformational erosion. Some dolomitic limestone or dolomite intercalations, devoid of fossils, occur in the highest parts of the formation, near the evaporites of the overlying Gipshuken Fro. At Svartperla, in the northeast of the area, 200m of deformed limestones were recorded by Birkenmajer (1964). This possibly suggests that there is a gradation into limestones in this direction. Palaeontology and age. The upper two thirds of the formation contains a diverse fauna including abundant brachiopods, and corals as well as trilobites, bryozoans, crinoids, bivalves, gastropods, nautiloids, foraminifers, trace fossils of marine worms, calcareous algae and land plant detritus. The lower part is unfossiliferous, except for indeterminable plant remains. Czerniecki (1969) concluded that the brachiopod assemblage has a Gzelian age although comparison of his species with those listed by Gobbett (1964) shows a much closer comparison with the ~Tyrrellfjellet Mbr (Asselian/Sakmarian) that had already been noted by Gobbett. The limestones in the upper part of the formation contain an abundant redeposited coral fauna, which was described by Fedorowski (1965, 1967) and Birkeumajer & Fedorowski (1980). This fauna is quite different from that of the Carboniferous Cadellfjellet Mbr which is beneath the Tyrrellfjellet Mbr and would seem younger. This supports evidence from the brachiopods. The fauna is dominated by the typically Permian genera Wentzelella and Londaleiastraea, and as Sakmarian species, common to the Tyrrellfjellet Mbr, seem to form a relict group; the age was revised to earlier Permian. The corals resemble Early Permian rugose corals of the Arctic Province. They also show an affinity to those of the Hambergfjellet Fm (Sakmarian-Artinskian; Fedorowski in Simonsen 1987).

185

Of the trilobites present, the Ditomopygae species has a close relative in the Gzelian Stage of Russia. A gastropod reported by Karczewski (1982) is very weak supporting evidence for a Permian age. A number of foraminifers were identified by Liszka (1964). Unfortunately, index fusulinids are lacking, and no direct comparison with the zones of Cutbill & Challinor can be made. The assemblage resembles the Asselian/ Sakmarian Schwagerina and Tastubia zones of the Urals. Nysaether (1977) from a litho-correlation with his Drevbreen beds, made the upper Treskelodden Fm equivalent to the lowermost Drevbreen beds in which he found Late Carboniferous (Gzelian) foraminifers. However, the fossil evidence make it seem more likely that the fossiliferous part of the Treskelodden Fm is laterally equivalent to the middle and upper Drevbreen beds and also the Tyrrellfjellet Mbr which are probably all early Permian in age. The lower, unfossiliferous beds may belong to the Late Carboniferous period. The presence of bioherms in the upper part was mentioned by Birkenmajer (1984); This provides a link with the lower Tyrrellfjellet Mbr and the Kapp Dun6r Formation of Bjornoya.

(b) Bellsund (e.g. at R e i n o d d e n ) The succession consists of alternating sandstones, siltstones, limestones and dolomites with subordinate amounts of conglomerates and shales, of which terrigenous clastics make up about 75% and carbonates 20% (Nysaether 1977). A more or less cyclic pattern is present, starting with carbonate followed by generally upward-coarsening clastics. The formation occurs below the Gipshuken Fm from Bellsund southwards until it is cut by the unconformity below the Hovtinden Mbr of the Kapp Starostin Fm. Nysaether (1977) correlated the formation at Ahlstrandodden with the Drevbreen beds which he described at Drevbreen in Torell Land. The formation is generally about 200 m thick, but on Kopernikusfjellet, only 15km south of Zittelberget, where it is of similar thickness, the formation is represented by only 35 m of conglomerate. Moreover, a similar distance of the south-southeast, the Drevbreen section has 180 m exposed. The top of the formation is marked by a conformable transition from grey carbonate above, belonging to the Gipshuken Fm. The base is unconformable and rests on Early Carboniferous rocks at Reinodden and directly on pre-Devonian basement elsewhere. The formation becomes increasingly conglomeratic towards the south, while north of Bellsund it appears to pass into the carbonates of the Tyrrellfjellet Mbr. The sandstones, which occur throughout, are well sorted, unimodal and fine- to medium-grained, with colours varying from brown to yellow, grey and reddish. They are predominantly quartzose and commonly conglomeratic. Cement is usually calcite or dolomite, occasionally chert. Rock fragments of chert, quartzite and quartz-schist are common. Feldspar is present, but not common, and heavy minerals are rare. The sandstones are thin- to thick-bedded with some cross-stratification. The conglomerates occur as lenses or well-defined thin beds throughout. They are composed of angular and well-rounded quartz, chert and quartzite pebbles which are usually less than 3 cm in diameter. The matrix is generally medium-grained sand. The shales are silty and fairly pale, green to dark grey, and are interbedded with the sandstones, especially in the upper part. The interbedded carbonates are thin to thick-bedded. The limestones are highly fossiliferous, sparry and sandy in the lower part at Drevbreen, though no fossils have been recorded elsewhere. At the top they are micritic, bioturbated, slightly bituminous and contain chert nodules; elsewhere they are of fine texture. Stylolites are common. The dolostones are grey, micritic and sandy, in places silicified and comonly vuggy with silica and dolomitefilled geodes locally. Nysaether (1977) distinguished upper, middle and lower units at Drevbreen on the basis of the type of carbonate present. The topmost 27 m contains only limestone, some of which is slightly bituminous, with chert nodules and a sparse fauna of bivalves and gastropods. The middle unit, 83 m thick, is characterized by dolostones containing corals, limestones being absent. Some of the dolostones are silicified and many are vuggy, with silica and dolomite-filled geodes in the upper part. In the lowermost 70 m exposed, the carbonates are almost exclusively limestone with abundant and varied fossils. Palaeontology and age. Almost the only fossils recorded from this formation are from Drevbreen where corals, brachiopods, crinoids, gastropods, bryozoans and fusulinids have been found in the lower unit (Nysaether 1977). The rich fusulinid fauna is of Late Carboniferous (Gzelian) age except at the top of this unit where there is a possible

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CHAPTER 10

transition to Asselian (Permian) affinities. The middle unit contains only corals, other fossils perhaps having been destroyed by dolomitization, while the upper unit has only a few gastropods and bivalves in the limestones. If the top of the lower unit marks the Carboniferous-Permian boundary, then the higher two units must be earliest Permian. Corals were reported in sands at Ahlstrandodden by a CSE party in 1985. Thus Nysaether's lithocorrelation with the Drevbreen beds is crucial to the dating of the Reinodden Fm. As the Drevbreen beds underlie Gipshuken Fm lithologies at Drevbreen, it seems a logical correlation.

10.3.4

Hyrnefjellet Formation (Treskelen Subgroup, Gipsdalen Group)

Exposed t h r o u g h o u t the H o r n s u n d area, the Hyrnefjellet F o r m a tion (Birkenmajer 1959; Cutbill & Challinor 1965; Siedlecka 1968; B i r k e n m a j e r 1964) is variable in thickness f r o m 30 m to 500 m. It is d o m i n a t e d by r e d - b e d s - m u d s t o n e s , sandstones, c o n g l o m e r a t e s a n d breccias, a l t h o u g h white quartz-rich sandstones and conglomerates b e c o m e increasingly significant t o w a r d s the top. It is also characterized by rapid lateral facies variations. In general there is m o r e c o n g l o m e r a t e in the west and southwest f r o m where the sediment is t h o u g h t to have been derived. The coarser lithologies c o m m o n l y show large-scale cross-stratification, channelization and erosive structures. Clasts include quartzite, limestone, dolostone, schists and red-beds; all are p r o b a b l y derived from a D e v o n i a n source. D e p o s i t i o n o c c u r r e d in a fluvial alluvial fan e n v i r o n m e n t , with channel, overbank, point-bar a n d possibly lacustine deposits present. Evolution o f the basin was controlled by local tectonics, resulting in occasional m a r i n e incursions. N o fauna have been f o u n d in the f o r m a t i o n to date, but it is considered to be of Late C a r b o n i f e r o u s age on the basis of regional correlations. The formation is not widely exposed, seen well at Kopernikusfjellet, and is controlled by Paleogene structures. It consists of 30 m of conglomerates there, 95m at Urnetoppen and about 70m are exposed at Hyrnefjellet. Thicknesses increase rapidly southeastwards to about 270 m at Adriabuka. Gjelberg & Steel (1981) gave a thickness of over 500m. The upper boundary of the formation is an unconformity at the base of the Treskelodden Fm, which separates the predominantly grey deposits of the Treskelodden Fm from the red Hyrnefjellet Fm (Birkenmajer 1984). The formation rests on deeply weathered and eroded shales of the Early Carboniferous Adriabukta Fm on Urnetoppen. It is not known elsewhere. The succession is characterized by repeated upward-coarsening sequences in which texturally immature red clastic sediments (mudstones and sandstones grading up into conglomerates and breccia) are overlain by texturally mature white quartzitic sandstones and thin conglomerates which increase in volume upwards. Three major lithotypes occur, sandstones (60%), conglomerates (30%) and shales (10%), rhythmically interbedded throughout the formation. They show rapid lateral facies variation and become more conglomeratic to the southwest. Red and pink sandstones, fine to coarse-grained and commonly cross-bedded and lenticular, predominate in the section on Hyrnefjellet but are less common to the west, where thicker rudaceous rocks occur. Finer grained rocks are more common to the east and north. The colouration is due to the relative abundance of hematite and ilmenite, which may be partly due to the derivation of these rocks from the ferruginous Devonian deposits. Cementation is commonly siliceousferruginous in the lower part, with the appearance of carbonate and sulphate higher up. Porosity is usually low. In contrast, at the top or base of the sandstone-conglomerate cycles, well-sorted, pale, quartzitic, fine- to medium-grained sandstones occur, showing occasional large-scale crossbedding (wedge, trough-shaped or planar), with white quartz-conglomerate intercalations. The red conglomerates which occur interbedded with the sandstones in the cycles are more predominant in the west. The beds are irregular, commonly lenticular and generally less than 1 m thick. Large-scale crossbedding is a frequent feature and the conglomerates usually fill channels eroded in the siltstones and shales. The conglomerates became finer upwards, passing into sandstones. The topsets of these cross-bedded units are commonly truncated by erosion. The matrix is usually red and arenaceous. Clastics are usually less than 10cm across, but may be up to 3 m. They consist of white or grey rounded quartz and sub-rounded to highly angular red and black sandstones. The clasts consist of white, pink,

grey and yellow quartzites, limestones, dolomites and schists as well as red quartzitic sandstones. The sandstone clasts may be intraformational, or derived from Devonian strata. The other lithologies are almost certainly derived from pre-Devonian rocks. A decrease in sorting and an increase in angularity occurs in a southwesterly direction, with a transition to very poorly sorted, angular breccias. At the base of the formation at Adriabukta and also at Meranpynten to the south, on the strongly weathered top of the Adriabukta Formation, are red medium to coarse breccias/conglomerates with angular to sub-angular fragments of red, yellowish and pink sandstone, 2-60 cm in diameter, and some 1-3 cm diameter rounded quartz pebbles, contained in a similar, but finer matrix. Stratification is absent and the fragments are chaotically arranged, with no imbrication. Horizontally bedded siltstones and shales form a minor constituent of the formation, but become more important to the east. They are red, purple and variegated due to the presence of iron oxides, and in general have the same mineralogy as the sandstones. Clay minerals are almost entirely absent, although muscovite, sericite, biotite and chlorite occur with finely divided quartz. Occasional ripple-marks can be found, some irregular and parallel, others of linguoid form. Casts of irregular large desiccation cracks up to 100cm in diameter occur at the base of the sandstones in places and small cracks are found in the siltstones. Truncated, convolute lamination, associated with fine-grained, laminated sandstones is also present in places. Palaeontology and age. The only recorded fossils are conifer branches found in the highest part of the succession at Treskelen (Birkenmajer 1984). As it is lies beneath the Treskelodden Fm, it may be of Late Carboniferous age. It is possible that it is the lateral equivalent of the lower Reinodden Formation/Drevbreen Beds, which are also cyclic and upward-coarsening. The lower unit of the Drevbreen beds is of Late Carboniferous age (Nysaether 1977). The formation post-dates the Early Carboniferous Adriabukta Fm (Tournaisian/Visean) and the Adriabukta tectonic phase which folded it, so may be Bashkirian to Moscovian in age. Cyclic conglomeratic red-beds are also found interbedded with marine sediments in the Bashkirian Ebbadalen Formation and the Bashkirian-Moscovian Landnordingsvika Fm, which could well be its lateral equivalents in central Spitsbergen and Bjornoya respectively. The Ebbadalen Fm also contains evaporites, which provide another environmental link in view of the sulphatic cement in the higher levels of the Hyrnefjellet Fm. The Moscovian Pyramiden Conglomerates (Minkinfjellet Fm) of central Spitsbergen, which overlie the Ebbadalen Fm are another possible correlative. They also contain conglomeratic red-beds derived from the west, interbedded with evaporites and marine carbonates. Similarly, the Moscovian T~rnkanten Fm of the Isfjorden area has cyclic red beds and marine limestones.

10.3.5

Sergeijevfjellet Formation (Billefjorden Group)

The Sergeijevfjellet F o r m a t i o n (Siedlecki 1960) consists of approximately 180 m of shales with fine-grained sandstones and siltstones. The sandstones are cross-bedded in places, the shales contain a b u n d a n t plant debris, and thin coals are c o m m o n . They were clearly deposited in a fluvial e n v i r o n m e n t with localized flood basins and swamps. T h e r e was no m a r i n e influence. It is of Early C a r b o n i f e r o u s age, p r o b a b l y Serpukhovian, although this is not well-defined. Early Carboniferous deposits in the northern Sorkapp Land-Hornsund area have been known since early investigations (Nathorst 1910; Freebold 1935; Orvin 1940). Siedlecki (1960) originally recognized the Sergeijevfjellet beds as a distinct unit, and they were given formation status by Cutbill & Challinor (1965). This is the youngest formation of the Billefjorden Group in this area. It crops out mainly in northwest Sorkapp Land and has also been recognised further east at Tsjernajafjellet.The formation lies beneath Triassic sandstones in northwest Sorkapp Land, separated by an angular unconformity. Further east, west of Tsjernajafjellet, it appears to be conformably overlain by the Bladegga Conglomerates (?lower Hyrnefjellet Fm: see Gjelberg & Steel 1981). The base of the formation is conformable with the massive sandstones of the Hornsundneset Fm. Siedlecki (1960) described the sequence on Sergeijevfjellet, which may be taken as the type section. The lithology is shaley: lighter grey and yellow to black shales, with intercalation of grey and brown fine-grained sandstone and siltstone. These latter interbeds are generally less than 30 cm thick, except for three major sandstones, 30, 20 and 15 m above the base. Some of the sandstone units are cross-bedded. Plant detritus is found in the shales,

SOUTHWESTERN AND SOUTHERN SPITSBERGEN especially in the upper part of the sequence. A coal seam 0.95-1.0 m thick occurs near the top of the section on Sergeijevfjellet, overlying carbonaceous shale. Additional coals, which are thin and clayey, are found in the black shales at the base of the formation. These shales also contain limonitic concretions. The shales contain plant fragments, including imprints of Stigmaria and stems of Lepidophyta. The formation has yielded abundant miospores (Siedlecki & Turnau, 1964) that indicate an Early Carboniferous age, probably earliest Serpukhovian (though possibly Late Visean-Late Serpukhovian). The assemblages found do not show any clear correlation with those described by Playford (1962, 1963) for the Billefjorden Group of Central Spitsbergen. Turnau suggested that this may be due to the younger age of the Hornsundneset and Sergeijevfjellet Fm.

10.3.6

Hornsundneset Formation (Billefjorden Group)

Originally recognized as a distinct unit by Siedlecki (1960), a n d given f o r m a t i o n status by Cutbill & Challinor (1965) this is the thickest, (750 m) and m o s t coarse-grained unit of the Billefjorden G r o u p in southern Spitsbergen. It is d o m i n a t e d by fine- to m e d i u m grained sandstones, a l t h o u g h granular a n d pebbly sandstones also occur. Clasts are derived f r o m P r e c a m b r i a n basement. Plant remains are c o m m o n a n d thin coal seams are present in places. It was deposited in the Early C a r b o n i f e r o u s (probably late Visean to early Serpukhovian) within an alluvial system, p r o b a b l y by braided streams. There is no evidence of a m a r i n e influence. The Hornsundneset Fm is a sequence of largely arenaceous around 700-750 m thick in the type area of northwest Sorkapp Land. It has been noted in inner Hornsund where it is 500-700 m. The formation lies conformably below the Sergeijevfjellet Formation. The lower boundary is a 60 cm quartzitic conglomerate lying unconformably on pre-Devonian basement in the type area. However, in inner Hornsund it overlies the Adriabukta Formation, apparently conformably (Gjelberg & Steel 1981). Siedlecki & Turnau (1964) and Birkenmajer (1964, 1979) showed the formation to consist predominantly of light grey, light yellow and brown quartzose sandstones, which are generally fine- to medium-grained although grain-size ranges up to 5 ram. They are thick-bedded (0.25-2.0 m), blocky and commonly contain large-scale cross-bedding (10-100 cm sets) which are generally indicative of eastward-flowing currents. The cement is siliceous, clayey or sideritic. Locally, plant impressions are common. Pebble-lag conglomerates occur occasionally at the base of the sandstone units in the lower part of the sequence and at the base, where it lies on pre-Devonian basement. They are slightly imbricated, and pebbles consist of rounded quartz and angular local Precambrian basement fragments. Inter-bedded layers up to 1 m thick of dark-grey, fine-grained sandstone, siltstone and shale occur in places, especially at the base. The dark colouration is due to the presence of carbonised plant remains and there are local coal seams. Plant remains have a widespread occurrence: Stigmaria and Lepidophyta (probably Cordaitales) have been found in the sandstones which indicate an Early Carboniferous age. Miospores have been investigated (Siedlecki & Turnau 1964) and, although not abundant, also indicate an Early Carboniferous age, probably earliest Serpukhovian, although possibly Late Visean.

10.3.7

Adriabukta Formation (Billefjorden Group)

U n c o n f o r m a b l y overlying D e v o n i a n basement, the A d r i a b u k t a F o r m a t i o n (Birkenmajer & T u r n a u 1962; Cutbill & Challinor 1965) consists of black, d a r k grey a n d green 'unfossiliferous' shales. Some thin sandstone interbeds and c o n g l o m e r a t e lenses are present. The unit was deposited in a shallow near-shore m a r i n e e n v i r o n m e n t , in a basin that b e c a m e increasingly restricted and possibly a n a e r o b i c later in the deposition of the formation. Plant imprints are quite c o m m o n and a p o o r l y preserved bivalve f a u n a has been found. As in the overlying two formations, the age is poorly defined but is p r o b a b l y T o u r n a i s i a n to Early Visean. The Adriabukta Fm crops out in the inner Hornsund area and Sorkapp Land, south of Treskelodden. It is absent in northwest Sorkapp Land,

187

where the Hornsundneset Fm lies directly on basement. This incompetent formation suffered severe deformation as a thrust horizon during the Paleogene West Spitsbergen Orogeny. Thicknesses are thus difficult to measure, but at least 500 m are present in central Sorkapp Land, thinning to about 300m in Adriabukta. The formation appears to lie conformably beneath the Hornsundneset Fm on Hyrnefjellet and in Sorkapp Land, but mid-Carboniferous uplift has, however, caused erosion of the top of the formation in places, where it is overlain by Triassic strata and the Hyrnefjellet Fro. It has a basal angular unconformity (of 10-20 ~ on both Devonian and pre-Devonian basement. The formation, which is about 300 m thick in the type section, consists predominantly of black, dark-grey and dark-green unfossiliferous shales. Thin arenaceous intercalations are quite common, these are generally poorly sorted, fine-grained sandstones which are usually less than 15 cm, but may be up to 50 cm thick. Graded bedding has been observed in some of these sands. Conglomerate lenses and layers, up to 2 m thick, also occur in the lower half of the sequence. They consist of angular and sub-angular quartz pebbles 0.5-5.0cm in diameter, contained in a sandy matrix. North of Adriabukta, there are basal conglomerates 2-3 m thick, lying unconformably on Devonian sandstones. The bottom 25m of the formation at Adriabukta is more arenaceous. It consists of grey, fine-, medium- or coarsegrained sandstones in beds 2-50cm thick, alternating with subordinate black arenaceous shales and conglomerates. The sandstones show crossbedding and the bottom of some beds contain groove- and prod-casts. A poorly preserved assemblage of unidentifiable concentrically-ribbed bivalves was reported by Birkenmajer (1964) from the basal arenaceous beds on Marietoppen (north of Adriabukta). The basal beds also contain frequent plant imprints, generally Lepidophyta, including Stigmaria 2-3 cm wide and up to 50 cm in length (Birkenmajer & Turnau 1962). Miospores (Birkenmajer & Turnau 1962) indicate an Early Carboniferous age. The occurrence of Velosporites echinatus in one of the lowermost samples (Sample A1) may indicate a Tournaisian age for this assemblage while Turnau stated that the presence of Densosporites cf. granulosus Kosanke in the lower sample (Sample A2) suggested a Visean age. However, a Tournaisian/Early Visean age for the lower samples (A1 & A2) is quite consistent with other palynological data. The sample taken from higher up in the shale sequence (Sample A3), yielded a much wider variety of miospores which indicate an Early Visean age.

10.4

Devonian strata

D e v o n i a n strata, so well developed in n o r t h e r n Spitsbergen (Chapter 8), a p p e a r n o r t h of H o r n s u n d a n d south in S o r k a p p L a n d as one f o r m a t i o n . The n o r t h e r n o u t c r o p has been described by B i r k e n m a j e r (1964) a n d the s o u t h e r n by D a l l m a n n et al. (C13G, 1993). B i r k e n m a j e r noted early historical events with the discovery o f the o u t c r o p by de Geer in 1899 a n d soon confirmed as D e v o n i a n (1910) a n d reported by N a t h o r s t (1910). T h e y were m o r e fully described by H o e l (1922, 1929) a n d included in the general a c c o u n t by Orvin (1940). Monaspis fragments (Heintz 1929) a n d ostracodes (Solle 1935) m a t c h e d the W o o d Bay F o r m a t i o n in the north. Orvin t h o u g h t that bivalves resembled G r e y H o e k F o r m a t i o n forms a n d suggested that the lower 150 m of red beds, limestones and c o n g l o m e r a t e s m i g h t correlate with W o o d Bay and the u p p e r d a r k 200 m unit with Grey H o e k strata, both m i d d l e D e v o n i a n . Sandstones and shales were taken as G r e y H o e k . Orvin postulated a substantial D e v o n i a n thickness south of the m a i n basin, to the north. T h e r e m a y have been a further 650 m as estimated, by B i r k e n m a j e r a n d possibly of W i j d e f j o r d e n F o r m a t i o n age with d a r k grey a n d black clastics.

Marietoppen Fm. Birkenmajer (1964) introduced the name Marietoppen for these rocks now referred to as a formation and described it as follows. Upper Mbr, 150-200m of green, grey-green or black shales cleaved and slightly phyllitized. Undetermined bivalves were collected (F6yn & Heintz 1943). Fish were found in 1960 (tuberculated arthrodire bones, Porolepis plates, holoptychiid scales and crossopterygian teeth). Only the lower part of the Grey Hoek Formation may be represented here. This is suggested by the bivalve ?Myalina formed in the Forkdalen Member of the Grey Hoek Fm. Murashov & Mokin (1979) correlated it with the Wijde Bay Fm.

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Middle Mbr, 550m of alternating green and red, often variegated arenaceous shales in layers 0.1-1 m intercalated with thin, yellow and pink, silty limestones of which the three uppermost yielded indeterminate ostracods, fish plates and teeth. There are no outcrops of this member north of Marietoppen but south of Hornsund the member probably occurs. Various (some problematic) finds of fossils led Birkenmajer to conclude that the member correlates with the Wood Bay Formation. Murashov & Mokin (1979) suggested Grey Hoek Fm age. Plant remains suggested Givetian age. Lower Mbr, 300-350 m of typically red (hematite) fine-grained sandstones, siltstones and arenaceous shales as well as calcareous sandstones and arenaceous limestones, the latter two facies are often nodular. There are also some variegated sandstones and quartzite with current bedding. Sedimentary breccias occur and may contain Porolepis type fragments. Fossil fish in the lower part of this Middle Division may correlate with the upper Wood Bay (i.e. Stjordalen Division). This is the most reliable biostratigraphic age estimate. At the base is a quartz conglomerate or sedimentary breccia with fragments of limestones and cherts from the underlying strata beneath an unconformity surface. Correlation of this unit is most likely with the Wood Bay Formation except that the Lower Wood Bay strata are not represented here. Birkenmajer (1964) gave detailed sections and profiles of this member in different localities. The later publication (Dallmann et al. 1993) concerns the outcrops in narrow strips on both sides of Samarinbreen south of Hornsund. The structure here is probably synclinal, the axis being occupied by the glacier and appears to have formed in Late Devonian or Early Carboniferous t i m e - probably Late Devonian Svalbardian diastrophism. Beyond this syncline erosion has removed Devonian strata. South of Hornsund the thickness of the Marietoppen Fm is about 800 m with possibly more beneath the glacier, compared with 1000m to the north. The lower contact is a distinct angular unconformity on metamorphic basement often with a weathered horizon and local basal polymict conglomerate or breccia with boulders up to 1 m.

With its descriptive text it addressed this problem thoroughly with extensive structural observations (Hjelle, Lauritzen, Salvigsen & Winsnes 1986). In the meantime Russian geologists had made general and geochemical observations (Turchenko et al. 1983). Hjelle had already noted the similarity between the metabasites and those of Chamberlindalen in north Wedel Jarlsberg Land and Turchenko extended this comparison with the basites in southwest Wedel Jarlsberg Land. Krasil'shchikov & Kovaleva (1979) made a different and comprehensive scheme for the whole of the west c o a s t depending heavily on the Polish work, extending it from the south. Barkhatov (1985) argued for a Vendian Complex with tillite and an older complex, but not mapped. The main difference between the above and a later interpretation (Harland, Hambrey & Waddams 1993) is that whereas the earlier authors agree that the tilloids at Kapp Linn6 in the north are Varanger glacial deposits (being rich in granitoid stones), Harland e t al. identified them with the Later Varanger glacial epoch. They correlated the diamictites and conglomerates in the south of Nordenski61dkysten with the earlier Varanger tillite horizon partly because they lack granitoids and are closely associated with basites. It was then postulated that most of the other rock units were found between the two tillite horizons and therefore that almost the whole outcrop of older rocks is of Early Vendian, i.e. Varanger age. As stated by Harland e t al. confidence in their interpretation here is less than that either north of Isfjorden or south of Bellsund. It is to a large extent influenced by comparison with these adjacent areas. Nevertheless this hypothesis was applied to describe the succession, while commenting on alternatives. The interpretation entails one major thrust fault from eastern Van Muydenbukta northwest and out to the sea north of Orustosen. This displaces the successions on either side and makes a feasible succession from the map.

10.5

10.5.1

Proterozoic strata of western Nordenski61d Land

Western Nordenski61d Land (west of Gronfjorden) boasts the classic Festningen section along the Isfjorden coast where Paleogene down to early Carboniferous strata are displayed in a sequence younging eastwards. The Orustdalen Formation rests with steep angular unconformity on the older rocks, which occupy a wide strandflat west of the mountains along which this unconformity is exposed south to Bellsund. To the west of this line, this strandflat, rarely exceeding 50 m in height above sea level, is named Nordenski61dkysten and is entirely occupied by Proterozoic rocks, save for at least two infaulted outliers of Carboniferous rocks. This line marks the western edge of the Central Basin. A convenient limit to our study area for this section is Gronfjorden to the north and Fridtjovbreen draining down into Fridtjovhamna in the south. This is approximately along the line of strike of the rocks which, continuing southwards across Van Mijenfjorden, include the remarkably linear Akseloya in our area and the western tip of Nathorst Land further south. So the area is neatly divided by the N - S unconformity into the Precambrian outcrop of Nordenski61dkysten, with the tip of Nathorst Land in the west and the obvious foldbelt with Carboniferous through Cretaceous rocks occupying the mountain front. Following the primary survey by Nathorst (1910), the principal investigations of this area have been carried out by Norsk Polarinstitutt geologists resulting in the following publications. Orvin's (1940) outline of Spitsbergen Geology paid particular attention to the western foldbelt and the basites which characterise the older rocks in the western coast. A planned series of investigations led to the definitive description of younger rocks at the Festningen section (Hoel & Orvin 1937). A general idea of the presence of tilloids and conglomerate at Kapp Linn6 and in the south at Kapp Martin was familiar. However, the first systematic survey of the whole of Nordenski61dkysten was by (Hjelle 1962, 1969) who took into account earlier Norwegian work. This work was later consolidated in the 1 : 100 000 geological maps with descriptions and, in particular, sheet B10G.

Sequence of the rock units

Kapp Linn6 Fm, 1+ km. Hjelle (1962) named the northern diamictite the 'Kapp Linn6 Tillite Series'. The top of the formation is not preserved being synclinal. The rock is stone-rich in an orange to grey-weathering psammitic schist, with thin greenish grey-weathering schist and sandy dolostone interbeds. Alternation with thicker more quartzitic layers up to 15 mm thick gives a visible banding. The stones are mainly quartzites, dolostones and granites. The base of the formation is at B~todden (B~todden member). Linn6fjella fro/unit, 1.2+ km. The outcrop in fig. 37 of Harland et al. (1993) is taken from Hjelle et al., B10G, (1986) and numbered '5?' and '3-4'. Hjelle (1962) proposed the name Linn~fjella for this thick conformable sequence of phyllite and quartzite with limestone beds. Malmberget unit/fm. Below the Linn&jella strata the map (B10G) shows three numbered units (3) limestone marble as at Malmberget; (2) phyllite; (1) quartzite as at Jainbreen. Hjelle et al. regarded this succession as comprising the lowest units in the area because they equated diamictites and conglomerates both north and south of the strandflat. For this unit the name: Malmberget fm with the three members 1 2 and 3 is tentatively suggested. L~gnesbukta Gp. Four formations are grouped here (Harland, Hambrey & Waddams 1993) and altogether are correlated with the Earlier Varanger glacial episode. L~gneset Fro. This is the Lfigneset tillite of Hjelle (1962, 1969) and is unit 10 of Hjelle et al. (1986). It is included in the Vendian tillite conglomerates of Turchenko et al. (1983) - their unit 8. It is well displayed at six localities other than L~gneset and includes the diamict formation at Slettneset and at Millarodden. At Lfigneset two N-S bands 70-90 m thick are separated by 100-125m of calcareous phyllite, white marble, oolitic limestone and pale green chloritic schistose diamictite. The two bands cropping out may be repeated by folding or faulting. The stones are mostly dolostone, quartzite and limestone with diameters typically 20-100 ram. Sedimentation was probably by ice rafting into a shallow carbonate sea with clastic and basic tuff input. The diamictite at Millarodden is correlated with this unit.

SOUTHWESTERN AND SOUTHERN SPITSBERGEN Diabaspynten is dominated by dark green amphibolite, probably lava flows and related tufts. They were noted by Orvin (1940) as gabbros along the west coast. Gravsjoen unit/division. This unit of varied facies is dominantly phyllites with metavolcanics and quartzites associated with massive basites. Thinner beds of dolostone and limestone are also present. Hjelle et al. mapped these rocks as units, 7, 6 and 9. From their map the unit would underlie the L~tgneset Formation. L~gnesrabbane Fro, 1-2 km. Following Hjelle (1969), his LSgnesrabbane calcareous beds are placed above the Kapp Martin conglomerates. The formation comprises two members. Upper (limestone) Mbr (light grey, laminated, partly oolitic interbedded with calc phyllite, black phyllite, white crystalline marble and minor conglomerates. Lower (dolostone) Mbr, 600 m, is a thick stone-free dolostone 600 m thick forming the rocky headlands west of Kapp Martin. Kapp Martin Fro, 800 m. This formation is dominated by massive polymict conglomerate occurring in beds 0.05-4 m thick in an assemblage of phyllites coarsely crystalline black limestone and subsidiary quartzite and dolostone. Waddams (1983) suggested deposition from sediment flows from material released by ice on an unstable slope.

10.5.2

Mineralization

Mineral occurrences, mainly of sulphides, invited mining that proved uneconomic. They occur by the coast at the northern and southern limits of the area. The rocks in between may also repay further investigation (Hjelle 1962). In the north at Kapp Mineral 2.5 km east of Isfjordradio Flood (1969) reported on the early workings where galena and some sphalerite occur in intensively brecciated rock in a zone a few metres wide near a fault zone. Further investigation showed the presence also of pyrite and chalcopyrite. However, continuation at depth was disproved. In the south 3 km west of the mining camp at Millarodden is a small island, Sinkholmen, which may be the richest exposed mineral deposit in Svalbard where 240 tons were mined mainly of sphalerite. Sulphides occurring in the breccia are sphalerite, galena and pyrite and in the associated calcite mass Flood (1969) recorded sphalerite, pyrite, chalcopyrite, bornite, idaite, chalcocite, neodigenite and covellite. Tetrahedrite occurred in both hosts; the gangue was fluorite and quartz in the breccia. The occurrences according to the above stratigraphy would be hosted in Late Varanger carbonates in the north and early Varanger in the south. Detailed stratigraphy was not recorded.

10.6

Proterozoic strata of western Nathorst Land and northwestern Wedel Jarlsberg Land

Observations in 1838 and 1839 were made from the ship L a R e c h e r c h e when interest was shown in mineral and coal occurrences. (Nissan 1941). Garwood & Gregory (1898), on Conway's expedition, first noted an ancient boulder bed thought to be equivalent to Reusch's Moraine in N o r t h Norway (Varangerhalvoya). The general outcrop pattern was established by Orvin (1940). This was supplemented by further mapping of the younger rocks by the Polish group about 1938 (Rozycki 1959). Much of the area of older rocks was surveyed systematically by the Wisconsin group led by Craddock (Kowallis & Craddock 1984; Craddock et al. 1985; Bjornerud 1990, 1992). All these observations were compiled in the 1:100 000 map sheet ( B l l G ) with the accompanying memoir (Dallmann et al. 1990). CSE stratigraphic traverses enabled the above results to be related to those from other areas in Svalbard (with respect to the older rocks) (Harland 1978; Hambrey & Waddams 1981; Waddams 1983; Harland, Hambrey & Waddams 1993). The main feature of the area is a northward-plunging open syncline which concentrates the youngest rocks at the north in the Kapp Lyell area. Older rocks then occur successively in a V outcrop

189

pattern. The variety of facies is such that correlation between one limb and the other is not at first obvious, but is confirmed by continuous mapping round the southern corner of the V. Thus even within this small area a duel nomenclature developed between the east and the west limbs (e.g. Dallmann et al. 1990; Bjornerud 1990; Harland et al. 1993). As in Oscar II Land, formations were assigned to two groups by Harland, Hambrey & Waddams (1993) for the rocks which were interpreted as Vendian and which overlie unconformably an older basement. There is general agreement on the mapping of sheet B 11G (Van Keulenfjorden). It is a key area in interpreting and correlating the strata to the north and south of the sheet. This general problem is reserved for discussion in Section 10.9 below.

10.6.1

Neoproterozoic succession of northwestern Wedel Jarlsberg Land

The following succession is based on early CSE work (Harland 1978; Hambrey & Waddams 1981; Waddams 1983), on University of Wisconsin work (Kowallis & Craddock 1984; Craddock et al. 1985) synthesized by Norsk Polarinstitutt mapping (e.g. Hjelle 1969; Dallmann et al. 1990, B l l G ) and followed with some reinterpretation by Harland, Hambrey & Waddams (1993) which forms the basis of the succession below and recounts how it came about (Fig. 10.4).

Kapp Lyeil Gp. This group comprises map units 27-31 of Dallmann et al. and three formations with ten members as listed below.

Lyellstranda Fm, 1.3kin. This formation was first described with two divisions by Waddams (1983b), the upper division (Lyellstranda) and the lower (Kolvebekken). He described the upper division, 3.0 km, as graded polymict conglomerate and buff-weathering dolomite psammite with occasional slate and calcareous phyllite containing dispersed dolostone and quartzite boulders up to 1.6m. He mapped six units by stone content and described the lower unit, 0.7 kin, as grey laminated quartzite and psammite with rare beds of conglomerate and occupying the coastal plain north of Longnedalen. It was not identified on the eastern limb of the syncline. However, the work by Craddock and colleagues was more detailed and their divisions are followed here with five members (unnamed). Mbr 5, Upper dolostone clast unit Mbr 4, Upper no dominant clast unit Mbr 3, Middle dolostone clast unit Mbr 2, Upper quartzite clast unit Mbr 1, Lower no dominant clast unit. Harland et al. (1993) concluded that the Lyellstranda Fm was influenced by a variety of glacially related processes. Good indications are dropstones in the psammitic diamictites formed by ice-rafting in a proximal glacio-marine environment. More distal glacio-marine conditions give phyllites with dispersed stones. The conglomerates are of similar material to the diamictites and probably formed from reworking of glacial deposits by gravity-driven sediment flows, as postulated from the older Kapp Martin Conglomerates (Waddams 1983b). Loading of the underlying bed is also evident. Logna Fro, c. 200 m. This is a soft, finely laminated dark grey phyllite with isoclinal folds parallel to the bedding. Dundrabeisen Fro, c. 1.4 km. This variable formation consists of alternating beds of psammite and phyllite, often with dispersed stones, conglomerate, and stone-rich diamictite. The stones (up to 1 m diameter) are mainly dolostone and quartzite with a minority of limestones and granites. Genesis was similar to the Lyellstranda Fm but reworking of till by subaqueous flows was less significant. Four members are listed following Craddock et al. as above. Mbr 4, Limestone clast unit Mbr 3, Lower dolostone clast unit Mbr 2, Lower quartzite clast unit Mbr 1, clast-poor unit Konglomeraffjellet Gp. This group was defined by four main formations in the east (Harland, Hambrey & Waddams 1993) following Hjelle (1969), Harland (1978) and Waddams (1983), and additional basal formation in the west above the unconformity. Different nomenclature has been applied to coeval rock units in east and west limbs of the syncline.

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CHAPTER 10

Fig. 10.4. Vendian geology of northwest Wedel Jarlsberg Land (redrawn from Harland et al. 1993).

Vestervfigen Fro, c. 340m in the east. Massive grey quarzites are interbedded with quartzitic slate and soft phyllite. It is equivalent to HjeUe's (1969) Konglomeratfjellet shale and quartzite beds. It is recorded only in the east and is similar to the rocks above, except for the absence of stones. Chamberlindalen Fm, about 1-2 km, in the east was described from the eastern outcrop (Harland 1978) where the succession is thicker, more varied and better exposed, but tectonically divided by thrust faults. The outcrops occupy the two broad valleys Chamberlindalen in the east and Dunderdalen in the west. Upper mbr, exposed southwest of Vestervfigen, is of grey slate with calcareous concretions, thin amygdaloidat lava flows and calcareous pyroclastic rocks. Middle mbr comprises well-bedded grey limestone, with dolostone clasts, above cream weathering dolostone, grey oolitic limestone and dark amygdaloidal basalt. Interbedded phyllites are not so well exposed. (Lower) Asbestodden Mbr is of basic lavas (some pillow tavas), pyroclastics and small intrusions interbedded with pelites and carbonates. At Asbestodden the basites have been altered to an asbestos-beating assemblage. Turchenko et aL (1983) described the igneous rocks as porphyritic picrites, both porphyritic and amygdaloidal basalts, andesites with myrmekites (up to 25% quartz), ophitic porphyritic gabbro-dolerites and volcanogenic sediments (e.g. green phyllites). All belong chemically to a single tholeiitic basalt-trachy-andesitic series.

Dunderdalen Fin, 1.9 kin, map unit 35 of Dallmann et al., is the western facies of the Chamberlindalen Fm. The outcrop was mapped by Orvin (1940) as a thick succession of pelite with discontinuous quartzites. Flood et al. (1978) and Harland (1978) suspected a pelitic schist and phyllite up to 1 km thick, and Bjornerud (t990) named it. Within a dominantly pelitic unit, quartzite and carbonate units, sometimes brecciated, often isolated, were interpreted as olistoliths. Whereas exposure is limited in the north, easy access is afforded from Storvika through Orvindalen or Tunsfjodalen in the south of the west limb of the syncline where way-up and relation to underlying strata is well confirmed. Sollwgda Fro, 300+ m in the east. Cliffs of carbonate units are conspicuous in the hills to the east of Chamberlindalen and with many, but minor, tectonic complications, lie beneath the Chamberlindalen Formation. Three members are easily distinguishable at a distance by colour; Upper mbr mainly bedded grey limestone and dolostone, Middle mbr yellow-weathering dolomitic marble and black bituminous limestone. Lower mbr pale yellow-weathering dolomite marbles with dark volcanics and silts. Slettfjelld~den Fin, 50-100 m. In the west this was referred to informally by Bjornerud (pers. comm.) as the Slettfjelldaten F m of dolostones and limestones with sedimentary breccias, digitate stromatolites and chert beds.

SOUTHWESTERN AND SOUTHERN SPITSBERGEN In the south, (at the head of Chamberlindalen) on the flanks of Konglomeratfjellet a substantial thickness of dolostone breccia/conglomerate with clasts up to 0.5 m long occurs at the base of the formation. In the southwest Hambrey estimated 285 m (ofCSE informal Orvindalen formation) suggesting offshore distal turbidites (phyllites) to shallow marine tidal facies, with oolitic and channeled stromatolitic dolostones. The dolostone diamictite could be a shallow marine deposit with some ice rafting. Fluykalven Fin (in the west). At Floykalven, south of Dunderbukta, is a diamictite rich in quartzite and carbonate stones the latter with occasional oncolites and stromatolites typical of the lower tillite facies already described north of Bellsund and Isfjorden. Bjornerud divided her equivalent Konglomeratfjellet Fm into two divisions: upper green-coloured, 500 m and lower brown-coloured, 400 m. East of Storvika in the south, two divisions were observed by CSE in 1983. Upper division, 330 m, dark grey phyllite with dispersed stones (dolostones, quartzite and vein quartz up to 0.35 m long, but no granitoids), which may be concentrated locally in a matrix of silty carbonate with chlorite in the foliation. Lower division (160m) light brown-weathering dolostone with dispersed clasts locally concentrated to a dolostone-quartzite conglomerate. In many respects this formation resembles the Trondheimfjetla Fm of Oscar II Land. Gaimardtuppen Fm (in the east). This name is applied to the lower of the three divisions which Hjelle (1969) included in his Konglomeratfjellet unit. Two members are distinguished after Harland et al. (1993). Upper mbr (= Gaimardtoppen division of Harland 1978) and phyllite limestone of the Wisconsin group (about 0.5km) is a dark calcareous sequence of psammites and pelites with dispersed stones; some facies are pebbly. A distal turbidite with dropstones is suggested. Lower mbr is the Konglomeratfjellet conglomerate beds of Hjelle (1969), Foldnutane division of Harland 1978, and Conglomeratfjellet Fm of Bjornerud (pers. comm.). Bjornerud (1990) noted that about 5% of the stones are granitic or gneissic and suggested that they could be derived from the Magnethogda sequence a few km to the east. ThiLq'jdlet Fro, 0-50m. This is a black, pyritic, phyllitic limestone (50-100m), with isolated beds of quartz pebble conglomerate. Below is the basal gritstone conglomerate 0-50m with dolomitic matrix resting on the unconformity seen only in the west (Bjornerud 1990). This unconformity is the base of the above which Harland, Hambrey & Waddams (1993) interpreted as the Varanger (Early Vendian) succession in the area with a total thickness of about 6 km.

10.6.2

Proterozoic basement

A m a j o r u n c o n f o r m i t y was m a p p e d in the west by the Wisconsin G r o u p ( B j o r n e r u d 1991) with little overlap b u t m a r k e d overstep, the underlying rocks h a v i n g suffered a m a j o r phase o f d e f o r m a t i o n before V e n d i a n time. I n the east where such an u n c o n f o r m i t y m i g h t also be expected the rocks are obscured by the wide R e c h e r c h e b teen a n d R e c h e r c h e f j o r d e n .

Nordlmkta Group (Proterozoic basement) in the west (Fig. 10.4). A sequence of eight formations was described by Bjornerud in her unpublished map, of which CSE observed the two lower formations in 1983 referred to as the Storvika formation. Not mapping the area CSE did not identify the unconformity in the two traverses made. The whole sequence mapped, and totalling 3.3 km consists largely of dolomitic marbles, phyUites and quartzites not much different from the overlying rocks, but with a distinctive structure. The succession below follows Bjornerud as printed by Harland et al. (1993, p. 102). (8) Dordalen Fro, 150m of heterogeneous dolostone and phyllite. (7) Thiisdalen Fro, 200 m of red brown phyllite and quartzite. (6) Trinutane Fm Ferroan doiostone and pink marble members, 150 m Resinous phyllite member, 30 m Pink cross-bedded quartzite member, 200m (5) SeljehaugfjeHet Fm Grey dolostone member, 150 m Black limestone member, 50 m (4) Botnedalen Fro, 300 m of platy limestone, dolostone and phyllite. (3) Peder Kokkfjeilet Fro, 600 m of sandy dolostone. (2) Evafjellet Fro, ?1 kin, of quartzite and phyllite. (1) Kapp Berg Fm, ?1 km, of phyllite and quartzite.

191

Magnethugda Group (the sequence to the east). East of Recherchebreen and Recherchefjorden is a sequence first referred to by the above name (Harland 1978) (Fig. 10.4). From Bjornerud's ms map and earlier work it seemed possible to correlate these rocks with the Nordbukta sequence so connecting the basal Vendian unconformity in the eastern limb of the syncline. Harland (1978) had noted also a possible similarity between the feldspathic rocks of Magnethogda and those gneissic bodies in the SkSlfjeUet Formation. However, further observations of critical localities in 1992 in the south from Isbjornhamna, Vimsodden, east of Recherchefjorden at MartinfjeUa and Berzeliustinden, supported the view that the Magnethogda does not easily correlate with any other sequence and that most likely the boundary between the central and western terranes of Harland & Wright (1979) passes through Recherchefjorden and Recherchebreen. The account of Dallmann et aL (1990) also implied doubt as to the Nordbukta correlation. Whereas the massive dolomitic marble (map unit 50 of Dallmann et al.) is extensive and might conceivably match one or more of the dolostones in the Nordbukta sequence, there is no match to the feldspathic rocks (map unit 49 augen gneiss and feldspathic quartzite). These rocks amongst so many dolostones, phyllite and quartzite are conspicuously pink. The outcrop area of map unit 49 beside Recherchefjorden is somewhat exaggerated: there is very little feldspathite along the foothills beside the fjord, it is mostly dolomitic marble. However, in the foothills of Berzeliustinden massive gneisses occur without interbeds of non-feldspathic facies though the facies do vary from feldspathic psammitic schists to augen schists and even coarse granitic gneisses. The rocks are intensely foliated and lineated. Rare specimens along the side of Recherchefjorden are almost mylonitic. No associated basic rocks were seen. Thus, the minor feldspathic development in the dominantly basic Sk~dfjellet Fm further south bears no comparison with the Magnethogda rock. Indeed no similar facies have been recorded in the south of Spitsbergen or in the West Spitsbergen Orogen. It is concluded that these feldspathic rocks, with their associated marbles, quartzites, phyllites and schists may belong to a different, once distant, terrane. The Van Keulenfjorden sheet B11G (Dallmann et al. 1990) maps a close association of units 49 (feldspathic rocks) and 50 (massive dolostone). Outcrops of Unit 49 extend about 7 km on each side of Antoniabreen and Unit 50 crops out intermittently for 20 km to the south. In the southern part of the sheet it is associated with units 51 to 55 described as carbonates, phyllites and quartzites. However, the adjoining preliminary sheet to the south, B12G (Ohta & Dallmann 1992), with slight overlap, maps the phyUites as G~shamna Formation and associated carbonates units 50 & 51 (to 14 N) as Hrferpynten Formation. The authors admit that their research is unfinished. It would also be affected by alternative interpretations of the succession to the south (as discussed below in Section 10.9)

Westernmost Nathorst Land. T h e small o u t c r o p of marbles a n d quartzites on the p r o m o n t o r y of M i d t e r h u k e n belong to the M a g n e t h o g d a sequence (as also m a p p e d by D a l l m a n n e t al. 1990)

10.7

Early Paleozoic and Proterozoic strata of southwestern Wedel Jarlsberg Land

This area lies south o f Torellbreen a n d n o r t h of H o r n s u n d a n d east as far as H a n s b r e e n , penetrating the s o u t h e r n part of the Central Basin. F o r descriptive convenience it is distinguished f r o m the area just treated (Section 10.6) because f r o m the Polish base at I s b j o r n h a m n a it has been intensively investigated by Polish geologists since that base was o p e n e d a b o u t 1957 as a c o n t r i b u t i o n to the I n t e r n a t i o n a l G e o p h y s i c a l Year. The base facilitated research in m a n y disciplines, especially Q u a t e r n a r y , and latterly seismic. F o r the p u r p o s e here, the bed-rock geology was comprehensively surveyed u n d e r the leadership o f K. B i r k e n m a j e r and published d u r i n g the years 1958 to 1994. W h a t e v e r was d o n e before has been superseded by Birkenmajer's t e a m so that their accounts f o r m the basis o f this section. M a n y others have visited the area, not least the I n t e r n a t i o n a l Geological Congress excursion in 1960. The Cambridge g r o u p f r o m visits on several occasions was able to f o r m i n d e p e n d e n t opinions on some questions which a p p e a r e d to be controversial. Latterly the N o r s k Polarinstitutt has c o l l a b o r a t e d in m a p p i n g the area: 1:100 000 sheet B12G (Ohta & D a l l m a n n 1992).

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Birkenmajer consolidated the results of the Polish Group north of Hornsund with those of the Norsk Polarinstitutt south of the fjord in a unified stratigraphic scheme developed over the years but essentially the same as that issued to the International Congress in 1960. This scheme in its latest available version is listed below but only down to formation rank. It has the advantage of a single tidy scheme for a large and complex area to which most maps have been related and it has been largely followed by Russian and Norwegian groups (e.g. Krasil'shchikov & Kovaleva 1979, Sheet C13G; Dallmann et al. 1993). The scheme has, however, been challenged (e.g. Harland 1978; Harland, Hambrey & Waddams 1993) on the grounds that stratigraphic units north and south of Hornsund and given the same name, do not necessarily correlate and that a major N-S terrane boundary along Hansbreen and west of H6ferpynten would mean that correlation east and west of that line is also suspect. The assumption that distant units correlate and so receive the same name leads to definitions that may not serve discussion well and possible reappraisal. It may be safer to introduce additional names and eliminate them if and when identity is established. A second cause for discrepancy between Birkenmajer's scheme and that adopted here is that formations are the primary rock units and their combination into groups may reflect different opinions as to their relationships whereas Birkenmajer defined groups and divided them into formations. Birkenmajer's scheme has priority and will be described first. However, the possibly different terranes will be described separately so as to enable discussion of correlation in Section 10.9. Birkenmajer's correlation of his units with those of Ny Friesland and Nordaustlandet are also in question because he assumed a relatively fixistic palinspastic relationship. Birkenmajer throughout indicated that the main groups were separated by diastrophic events which are inserted in the following table in upper case lettering.

*Brattegga (amphibolite) Fm, 300-500m *Angellfjellet (amphibolite) Fm, 0-200 m *Gangpasset (migmatite) Fm, 0-100 m *Torbjornsenfjellet (amphibolite) Fm, 350-600m Steinvikskardet Fm, 100-250 m Gulliksenfjellet (quartzites) Fm, 500-850 m Isbjornhamna Gp Revdalen Fro, 250-350m Ariekammen Fm, 500-1500 m Skoddefjellet Fro, 1000+ m These older rocks, listed above, generally have been referred to as Hecla Hoek. However, on the basis of not assuming correlation until it has been satisfactorily demonstrated this name is avoided here preferring the more descriptive 'pre-Devonian' or 'basement' attribute. Moreover, around eastern Hornsund overlying Devonian strata have been mapped and dated palaeontologically. The successions are described below, west and then east of Hansbreen.

Stratigraphic scheme from Birkenmajer 1978 and 1992

Duneyane Fro, 750m. A dolomitic rock forms much of Dunoyane. It is of light dolostones interbedded with dolomitic oolites and pisolites with Collenia. A t Storoya off Dunoyane it appears to pass upwards into black quartzite and quartzite schist. It has been correlated with Winsnes' Oolitic Limestone Member of the H6ferpynten Formation south of Hornsund which Birkenmajer named as the Dunoyane Member. There it is only 40m thick and was also correlated with the 25m north of Hornsund at Fannytoppen. A distinct name is preferred so as not at first to assume identity. According to Birkenmajer this would be the youngest formation in the Vimsodden-Isbjornhamna terrane, younger than the SlyngfjeUet Conglomerate. It is an isolated island outcrop with no direct evidence as to its relationship with the other rocks of our terrane. The nearest mainland rocks belong to the Vimsodden Subgroup. Projection of local dips suggest that it may be older than the Vimsodden Subgroup. Both formations have similarities with the Akademikerbreen Group of Ny Friesland and have been so correlated. If this be correct the Dunoyane Formation would be pre-Vendian and Late Sturtian or Riphean. Slyngfjellet (conglomerate) Fro. This distinctive formation is the uppermost in the succession both in Birkenmajer's description and his map. The fullest descriptions were given by Birkenmajer (1990, 1991, 1992). At the type locality, Slyngfjellet, the formation may be 500m in this area and divides into two informal members. Upper mbr. Green meta-conglomerate with subordinate sandstone with siltstone and shale intercalations of yellow/brown conglomerate. The unit at the type locality is a green meta-conglomerate with 70 to 80% light green/ yellow lenticular or tabular sharp-edged, sometimes subrounded, homogeneous or laminated quartzite clasts 1-30 cm in diameter; some quartzite slabs <50• 50x 10cm, dolostone slabs 10 to 20cm• and 'red shale' 5-10 cm diameter. The whole is supported by 20-30% green chloriterich schistose matrix. Passing northwards the stones are less tectonized being typically subrounded and in a matrix, often black slate rather than chlorite schist. WBH notes that this facies compares closely with the Gaimardtoppen Fm further north. Lower mbr. Yellow/brown meta-conglomerate. Jens Erikfjellet contains an apparently conformable bed within the Jens Erikfjellet Fm (below the Deilegga Group) which Birkenmajer listed as representing the lower

NY FRIESLAND OROGENY (of Harland 1959) Hornsund Supergp (two groups) Sorkapp Land Gp (Ordovician) Hornsundtind (limestone) Fm Tsjebysjovfjellet (limestone) Mbr, 400 m Rasstupet (limestone) Mbr, 80 m Nigerbreen (limestone) Fm, 120 m Dusken (limestone) Fm, 100 m Luciapynten (dolostone) Fm, 400 m Weiderfjellet (quartzite) Fm, 300 m HORNSUNDIAN DIASTROPHISM Sofiekammen Gp (Cambrian) Nordstetinden (dolostone) Fm, 150 m Gn~lberget (marble) Fro, 250-300 m Slaklidalen (limestone) Fm, 10-120 m Vardepiggen Formation, 130-215 m Bfftstertoppen (dolostone) Fro, 100-150m JARLSBERGIAN DIASTROPHISM Sofiebogen Gp (Proterozoic) G~shamna (phyllite) Fm, 1500-2500 m H6ferpynten (dolostone) Fm, 120-710m Slyngfjellet (conglomerate) Fro, 10-500m TORELLIAN DIASTROPHISM Torellbreen Supergp (three groups) Deilegga Gp Bergskardet Fm, 500+ m Bergnova Fro, 1800m Tonedalen Fm 1200+ m WERENSKIOLDIAN DIASTROPHISM Eimfjellet Gp (two subgroups plus two formations) Vimsodden Subgp (three formations, Birkenmajer 1993) Jens Erikfjellet Fm, 1100m Elveflya Fro, 200 m Nottinghambukta Fm, 1550m Skgdfjellet Subgp (four formations*)

10.7.1

West of Hansbreen

West of Hansbreen and north to Torellbreen there is a well exposed terrane which, in spite of intense tectonism, with many thrust units and few continuous sections, has yielded a coherent stratigraphy described in many papers from Birkenmajer (1958) to Birkenmajer (1993). His 1991 papers describe the earlier work with valuable detail hitherto not generally available. This immense contribution is accepted here with only minor comment. The scheme has been broadly accepted by the Norsk Polarinstitutt in their l:100 000 map C12G (Ohta & Dallmann 1992) and also by the Russian geologists under the leadership o f Krasil'shchikov who have independently worked there. This particular area is referred to here as the Vimsoddenlsbjornhamna Terrane. The succession is summarized as follows, except the Dunoyane Formation is probably not the youngest (see Fig. 10.5).

SOUTHWESTERN AND SOUTHERN SPITSBERGEN

193

Fig. 10.5. Stratigraphic schemes for the Precambrian succession of southern Wedel Jarlsberg Land.

member. From these observations and without knowing the distribution of the Deilegga divisions it was probably mistakenly concluded (Harland, Hambrey & Waddams 1993) that the Slyngfjellet Fm was older than the Deilegga rocks. It now appears that the Slyngfjellet facies may not be limited to one horizon. Deilegga Gp. Little had been written about the three formations in his Deilegga Gp until Birkenmajer (1992, 1993) described them as follows. Bergskardet Fm >500m. This is a green phyllite-slate and chlorite complex with light quartzite intercalations Bergnova Fro, 1800m. This was the middle Deilegga unit prior to Birkenmajer (1975). Green to black, yellow weathering phyllite and chlorite slates with intercalations of thin dolostone, limestone with pyritiferous shale and secondary gypsum. Birkenmajer (1960) referred to alum shales in this division. Tonedalen Fro, 1200m. The following three-fold division was formally defined by Birkenmajer (1993). Iskantelva Mbr, 100-1100m green and black (yellowish weathering) phyUites, slates and chlorite schists with thin dolostone and quartzite intercalations in the lower part and in the upper 300m pink-white quartzites. Czerny et al. (1993a, b) compared the lithology with that of the G~shamna Fm but correlation was rejected by Birkenmajer because of the stratigraphic order. On the other hand the map B12G (1992 edition) mapped this unit as G~shamna; but see discussion in section 10.9 Nannbreen Mbr, c. 50m is a sequence of carbonates, arenaceous and phyllitic rocks. Lipertoppen Mbr, c. 150m thins to 10m to NW is a quartzite metaconglomerate unit of mainly calcareous quartzite clasts with a minority of black marble and pink rhyolite volcanic clasts. Eimfjellet Gp, c. 4.3km (Birkemaaajer 1958, 1992). The group comprises the Vimsodden and Sk~lfjellet subgps and two formations beneath them: Steinvikskardet and Gulliksenfjellet (from official place name spelling Gullichsenfjellet). In 1991 Birkenmajer correlated the Skalfjellet

Subgroup with the two lower members of the lower (Nottinghambukta) formation of the Vimsodden Subgroup (Fig. 10.5). Vimsodden Subgp, c. 3.3 km. The Vimsodden 'series' was introduced as the lateral equivalent of the Sk~lfjellet 'Series' in the upper part of the Eimfjellet Fro. It consists of phyllites and slates intercalated with amphibolites, limestones, and varved quartz schists containing quartzite boulders first thought to be a marine tillite (Birkenmajer 1958, 1960). It was redefined and reinterpreted (e.g. Birkenmajer 1991, 1993). There were two constituent formations Elveflya and Nottinghambukta each with three members. In Birkenmajer's (1993) revision the uppermost member was separated as the Jens Erikfjellet Fm leaving the Elveflya Fm with the two lower members. Jens Erikfjellet Fm (Czerny et al. 1992; Birkenmajer 1993 raised from Member rank), c. 1100m consists mainly of metabasites, pillow lavas and tufts with subordinate paragneisses and schists. Rock types include greenstones and greenschists (the bulk of the formation), acid metavolcanics including porphyrites and minor muscovite graphite and quartzite schists with calc-schist intercalations and dolostone or dolomitic limestone lenses. At Elveflya is a green meta-conglomerate, 1-5m of tectonized quartzitic and granitiod clasts. Elveflya Fro, 2000 m (divided by Birkenmajer 1993) Skoddebukta Mbr, l l00m pale quartz-schists and quartz-chlorite schists and some black muscovite-graphite schists with amphibolite and quartz~ albite paragneiss intercalations. Middle Mbr, 300m quartz schists with three grey limestone marble bands. Vimsa Mbr, 600m (Lower member of Birkemnajer 1992). Light bluish quartz- and quartz-muscovite schists with two main meta-tilloid units separated by laminated quartz sericite schists. The metatilloids were first suggested as tillite by Birkenmajer in 1958, an opinion shared after further visits (Harland 1978; Harland, Hambrey & Waddams 1993). Alternative explanations have been suggested such as by tectonic shearing of sandy current ripples in a flaser-bedding association

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(Birkenmajer 1991, p. 44). However, the majority of outsize clasts better fit the hypothesis of ice-rafted s t o n e s - mainly of dolostone with minor amounts of quartzites and at least one observed dropstone structure in a less intensely deformed facies. Flaser structure, although also present, could not account for the composition, sizes and shapes of the stones. The preferred glacial origin need not conflict with Birkenmajer's flaser hypothesis because they relate to different objects. The whole formation is highly compressed and sheared typically producing a crenulated phyllite in which the outsize clasts have been d e f o r m e d - some flattened and some elongated, e.g. 1 5 • 2 1 5 lcm. Nottinghambukta Fro, c. 1.5km (divided Birkenmajer 1993). The formation is well developed at the coast of the eponymous bay. Kvisla Mbr, 700 m varied. Pyttholmen Mbr, 500 m of green muscovite- or chlorite-epidote schists. Kvislodden Mbr, 350 m of slates, paper shales and phyllites. Skhlfjellet Subgp. The subgroup has been described by Birkenmajer & Narebski (1960) Narebski (1960a, b) and Smulikowski (1960a, 1965, 1968). It consists largely of metamorphosed basic magmatic rocks including pillow lavas. This subgroup occupies ground to the south and south east of the Vimsodden Subgroup. Brattegga (amphibolite) Fro, 300-500m. Dark green to black epidote amphibolites with a structure suggestive of pillow lavas. This metavolcanic complex contains thin quartzite intercalations. AngeHfjeHet (amphibolite) Fin, 0-200m. Coarse-grained light green massive epidote amphibolites similar to gabbro in appearance. Gangpasset (migmatite) Fro, 0-100m. Comprises migmatites and granitoid rocks occurring as lenticular body within a predominantly amphibolite complex. It contains a meta-tilloid psephite unit up to 15 m thick. TorbjornsenfjeHet (amphibolite) Fro, 350-600 m. Medium to fine-grained epidote to biotite amphibolites are the major components alternating with fine green to dark green quartz-feldspar-hornblende-mica schist. The Angellfjellet Fm and the 'Gangpasset' (migmatite) Formation appear to be local facies or members of the Brattegga (amphibolite) Formation which correlates best with the Pyttholmen member of the Nottinghambukta Formation. Correlations of the Torbjornsenfjellet Formation with the Kvislodden member is not so obvious. The geochemestry of these rocks has been described by Narebski (1960) and Smulikowski & Kozlowski (1994). The other facies of interest, interspersed within the basic volcanics and gabbro-rich beds of the SkAlfjellet Subgp, are the feldspathic rocks which appear as lenses of granitic gneiss. Krasil'shchikov & Koroleva (1979) suggested an origin as rhyolitic tufts or arkoses. Limited observations by the Cambridge group recorded no evidence of original magmatic structure. Steinvikskardet Fro, 100-250 m (Birkenmajer 1958-1975). Greenish micaquartz and biotite-epidote~luartz-schists in bands 10-50cm thick, alternating with light quartzites and green concordant amphibolites. Transitional boundary at concordant amphibolite. Gulliksenfjellet (quartzite) Fro, 500-850m (Birkenmajer 1958: raised to formation rank 1975) is formed of well-bedded, light coloured, laminated quartzites in beds 0.5-10m alternating with green to black chlorite-biotitemuscovite schists with intercalations of green amphibolites and some albite and microcline-bearing rocks. Gulliksenfjellet Fm rhyolite porphyry clasts in the Pyttholmen Fm gave a zircon magmatic age of 1130 Ma (Balashov e t al. 1995). The contact with the underlying Revdalen Fm is generally tectonic and may have been unconformable, but was mapped concordantly by Czerny e t al. (1992). Isbjornhamna Group, 2-3 km (Birkenmajer 1958-1992; Smulikovski 1960) The Isbjornhamna Gp, comprising the Revdalen (top), Ariekammen, and the Skoddefjellet fms, is the oldest complex of rocks exposed in the Vimsodden-Isbjornhamna terrane. The Revdalen Fm (250-300 m) is of grey greenish to yellowish garnet micaschists (muscovite or bi-mica) and paragneisses without marble or calc-schist intercalations, which distinguish and define the underlying formation. The Ariekammen Fm (500-1500m) consists of psammitic to semipelitic schists alternating with grey marbles, many of the schistose beds are brown and have a recognizable calcite content and may be transitional to the marbles. The Skoddefjellet Fm (> 1000m) consists of grey, green to yellowishweathering garnet mica schists, predominantly with muscovite and paragneisses, with plagioclase and biotite as described by Smulikowski (1960b, 1965).

Isotopic ages have been proposed for these oldest rocks as follows: Gayer e t al. (1966) found a K - A r age for biotite from the lowest formations as 565 and 594 Ma. Peucat, Dallmeyer & Teben'kov (Ohta 1992) from zircons gave tentative ages of 1130 and 1135 Ma. Teben'kov e t al. (in prep) recorded garnet twomica schist with a preliminary metamorphic Rb-Sr age e. 940-950 Ma (text of map C13G, p. 42). An alternative scheme of Czerny e t al. (1992) redefined the Eimfjellet Gp as below. That part of their scheme is favoured here because it distinguishes established early Neoproterozoic strata from the overlying Elveflya Fm. Thus units in Birkenmajer's Vimsodden Subgroup are separated by the major Vimsodden-Kosibapasset Fault (VKF). Eimfjellet Gp (Middle Proterozoic) s e n s u Czerny e t al. Pyttholmen Fin (with acid igneous rocks from which Balashov e t al. (1995), suggested a magmatic age of 1200 Ma, a regional metamorphic age of 930 Ma, and with inherited zircons of 2500 Ma).

GulliksenfjeHet Fm Bratteggdalen Fm Skfilfjellet Fin (in part equivalent to the upper two formations). The Sk~dfjellet rocks yielded Rb-Sr and zircon (magmatic) ages of 1100-1200 Ma (Balashov e t al. 1996b) and detailed petrological data.

Eimfjellbreane Fm Skjerstranda Fm The Eimfjellet Group follows conformably on the Isbjornhamna Group. This reclassification is supported by Birkenmajer's correlation table (1992, p. 29) simplified here Fig. 10.5. In this work the Vimsodden-Kosibapasset Fault is taken as marking a major break in the sequence (i.e. a faulted unconformity) which divides a more restricted Vendian Vimsodden Group above (to the north) from a much older basement comprising a newly defined Eimfjellet Group (Czerny e t al. 1992) and a relatively concordant Isbjornhamna Group below of established mid-Proterozoic age (Balashov e t al. 1995). Formations are the observed stratal units which may (to express an opinion about their relationships) be combined into groups. The opposite procedure to define groups and divide them into formations has led to some of the above confusion and is not an international convention.

10.7.2

Early Paleozoic and Proterozoic strata east of Hansbreen

T h e rocks in this s u b t e r r a n e are described as in B i r k e n m a j e r ' s sequence, a n d m a i n l y with his description, while using s o m e o t h e r n a m e s to a v o i d implicit c o r r e l a t i o n either west o f H a n s b r e e n or south of Hornsund.

Hornsund Supergp Sorkapp Land Gp, 1400 m no fossils have been recorded from Wedel Jarlsberg Land. By correlation with Sorkapp Land fossiliferous units the group is Canadian in age. Birkenmajer (1978) consolidated earlier results from Major & Winsnes (1955) for Ordovician and Cambrian stratigraphy of the Hornsund area (southern Wedel Jarlsberg Land and Sorkapp Land). His accounts were given according to a unified nomenclature for the whole of southern Spitsbergen. Hornsundtind (limestone) Fro, 500 m in Sorkapp Land. The formation is of light to dark grey to black bituminous limestones passing down transitionally into pinkish grey limestones. Whereas this unit is best developed in Sorkapp Land it crops out as the most extensive unit throughout the length of the mountain range (Luciakammen) that extends north from Luciapynten nearly 20 km to the northernmost exposure at Aulrabben with only one small outcrop east of Mfilbacherbreen (Birkenmajer 1978, fig. 2). Two members have been distinguished south of Hornsund and no fauna was described from Wedel Jarlsberg Land. The correlation is lithological with that to the south and the fauna is as described in the south by Major & Winsnes (1955). Nigerbreen (limestone) Fro. The formation occurs only in the southern part of Luciakammen and at Fiskcknatten in the north but appears to wedge out between. It is defined in Sorkapp Land where it is 80 m thick but is probably less in Wedel Jarlsberg Land where it hardly shows on the map (Birkenmajer 1978, fig. 2). Dusken (limestone) Fro, 100m. This thin-bedded, grey, black-laminated limestones with yellow laminae and with black cherts is defined in Wedel Jarlsberg Land. It is thinner in Sorkapp Land (20-30m). It crops out through most of the length of Luciakammen. No fossils have been recorded from the formation.

SOUTHWESTERN AND SOUTHERN SPITSBERGEN

Luciapynten (dolostone) Fm, 400 m. The formation is made of dolostone, calcareous - massive or thick-bedded with black or blue chert intercalations with sponge-like (stromatolitic) structures. It is defined in Wedel Jarlsberg Land at Luciapynten and is exposed through the southern part of Luciakammen, the lower strata being mostly covered by ice. Wiederfjeilet (quartzite) Fro, 150m. This arenaceous, quartzite and dolomitic formation is defined in Sorkapp Land, but extends north into Wedel Jarlsberg Land where an extensive outlier of the lower member rests directly on Sofiekammen Group rocks (Cambrian) at Nordstetinden. Goi~sbreen Mbr (very limited occurrence) in the Sofiekammen range was noted by Birkenmajer and no outcrop is seen on his map (fig. 2). It is of dark grey calcareous shales and thin blue quartzite layers. Paierlbreen Mbr, 150m of dolomitic sandstone with fragments of the underlying Nordstetinden (dolostone) Fro. Sofiekammen Gp, 635-850m (Birkenmajer 1958, 1978) Nordstetinden (dolostone) Fro, 150m (Birkenmayer 1958, 1978) Nordstebreen Mbr, 150m (Birkenmajer 1978), of platy dark grey-black (yellow-weathering) dolostone in three layers, 1-10cm, alternating with yellow mainly dolostone 1-2 cm layers. Hansbreen Mbr, 100m (Birkenmajer 1978) of light or dark grey to bluish (yellow weathering) massive or poorly bedded dolostone. Grey dolostone sometimes alternates with black bituminous dolostone. Gnfilberget (marble) Fro, 250-300m (Birkenmajer 1959, 1978). Massive limestone marble with pink calcite or red jasper veins; no fossils were recorded. Slaklidalen (limestone) Fro, 25-120 m (Birkenmajer 1975, 1978). Black to grey limestone is sometimes dolomitic, bituminous or arenaceous and often thin-bedded; correlated with the richly fossiliferous Slakli Subgp of Late Early Cambrian age (Major & Winsnes 1955), but fossils in Wedel Jarlsberg Land were not specified. Vardepiggen Fro, 110-130 m Flogtoppane Mbr, 30-40 m, yellow dolostone or grey limestone pass down into black to grey graphitic shales often with sedimentary breccias. Midifjellet Mbr, 5 - 5 5 m , black to dark grey limestone, often shaly or phyllite with indeterminate trilobite fragments. Olenellusbreen Mbr, 44-65 m (Birkenmajer 1978) of green to black shale with sedimentary breccias with flattened imprints and exoskeletal fragments of olenellids and anemone burrows Dolopichnus. A late Early Cambrian age was suggested. Blfistertoppen (dolostone) Fro, 100-150m. Blue-black, yellow weathering arenaceous dolomitic rocks passing into pure dolostone or dolomitic limestone. No fossils are recorded from Wedel Jarlsberg Land. A basal conglomerate is said to rest with angular unconformity on the Bogstranda unit which is correlated with the Ggtshamna phyllite Fm (south of Hornsund); but the section at Islova-Lovetanna (Birkenmajer 1978, p. 14) shows a concordant relationship. Sofiebogen Gp. This is part of the Precambrian succession and was described by Birkenmajer (1958 et seq.), as at the beginning of this section, for the whole of south Spitsbergen. However, other names have been introduced here (e.g. from Harland 1978) for this terrane (east of Hansbreen and north of Hornsund) to facilitate discussion of correlation between the terranes. They are distinguished by asterisks. The sequence appears to be continuous and demonstrably younging to the east so that the rocks have been overturned with a steep westerly dip. *Bogstranda unit, 2.0km. This unit has been correlated with the Gfishamna Fm south of Hornsund and a separate formal name may not be necessary except for the purpose of discussion so as not at first to assume identity. The rocks are better developed here and their relation to the older beds is well exposed. The strata are very largely pelitic, intercalated with seven quartzite shale horizons (up to 60m) in the lower 1000 m where some dolostone beds occur up to 5 m. A limestone bed occurs above the quartzite beds. The pelites are phyllites in many shades of green and black. The former probably indicate a volcanic component and the latter a biogenic input in the absence of volcanic material. The quartzite shale horizons, the quartzitic sandstones and/or quartzites are white to rusty brown weathering. Some chert fragments occur at their soles and the associated pelites may be graphitic. At Bogstranda the dolostones may contain silicified ooids. The limestones are reminiscent of Cambrian facies. Although the thickness south of Hornsund may total more than 3 km the lower contact there is faulted and the missing beds there may be represented by the phyllites with some of the seven quartzite horizons at the base of the Bogstranda unit. On the other hand the upper Bogstranda contact is faulted and may have cut out a substantial thickness of relatively uninterrupted phyllites.

195

*Fannytoppen Fm, c. 120m Harland (1978); Harland, Hambrey & Waddams (1993). This unit has always been correlated by Birkenmajer (1958-1972) with the H6ferpynten Fm south of Hornsund, so making the older strata pre-H6ferpynten. This correlation has been questioned (Harland 1978-1985, Harland et al. 1993). Pisolific mbr, 0 - 2 4 m dolostone with fine oncolitic texture. Radwanski & Birkenmajer (1977) described and correlated it with the H6ferpynten Formation south of Hornsund. Dolostone mbr, 14m in which stromatolites were observed with T. S. Winsnes (Harland et al. 1993). Limestone mbr, 80m. This is Birkenmajer's Fannytoppen Mbr of the H6ferpynten Fm of Major & Winsnes (1955) to the south. *Fannypynten Fm (about 500m). The Fannypynten Fm is a polymict reddish diamictite with a great range of stone sizes up to boulder size, and of composition of stones (quartzite 60%, feldspathites (granitoids) 20%, dolostones 15%, limestone 5%). They are either dispersed or in contact. Harland (1978) and Harland et al. (1993) concluded from the thickness, poorly sorted nature, high stone content, remnant lamination that the formation developed in a proximal glaciomarine environment or as waterlain till. This unit is sheared so that many stones and boulders are elongated and flattened. *Unnamed division (about 300 m). A break in the exposure (at the gravel tombolo spit west from Fannytoppen) suggests that less resistant rocks, possibly phyllites, may intervene. Hansvika Fm (about 500 m). Occupying the rocky promontary at the end of the tombolo is a polymict diamictite of tilloid appearance and greyish colour with dispersed dolostone, limestone and quartzite and no feldspathic rocks. The colour contrast with the Fannypynten Formation was commented on by Birkenmajer who referred to both formations as the Slyngfjellet conglomerate at the base of his Sofiebogen Group. His two members upper and lower were, however, probably described from Slyngfjellet, because his upper member was described without feldspathic clasts which are so conspicuous from their colour at Fannypynten. The type Slyngfjellet conglomerate might correlate with the Hansvika but not with the Fannypynten Fm. Harland (1978) and Harland et al. (1993) concluded a similar mode of formation as the Fannypynten Fm. It was referred to informally as the Hansbreen unit (Harland 1978) but Hansbreen Mbr of the Norstetinden Fm was used formally by Birkenmajer (1978a). To avoid confusion, Harland, Hambrey & Waddams (1993) used the only other name available, and Hansvika is appropriate.

10.7.3

Comparison of stratal schemes for southwest Wedel Jarlsberg Land

F i g u r e 10.6 c o m p a r e s five different s t r a t i g r a p h i c schemes. F o u r m a y be culled f r o m the literature a n d were p r o p o s e d at a b o u t the s a m e time a n d t h e fifth is t h a t w h i c h c u r r e n t l y fits the a u t h o r ' s field i m p r e s s i o n s in the light o f recent p u b l i c a t i o n s i n c l u d i n g the i s o t o p i c age d a t a o f B a l a s h o v et al. (1995). E a c h p o s i t i o n c h a n g e s w i t h evolving investigations so n o single p u b l i c a t i o n e n c a p s u l a t e s essential viewpoints. I n o r d e r n o t to a t t r i b u t e an o p i n i o n unfairly to a n y a u t h o r , f o u r initials are u s e d for the i n t e r p r e t a t i o n s s c h e m a t i z e d for their distinctive differences. B refers to an i n t e r p r e t a t i o n o f B i r k e n m a j e r ' s c o n t r i b u t i o n (1958-1993, especially 1992) a n d his 1990 m a p . C refers to his colleagues C z e r n e y et al. (1993) a n d is based o n their detailed m a p o f a critical b u t m u c h smaller area. O refers to the N o r s k P o l a r i n s t i t u t t m a p s , especially to O h t a & D a l l m a n n (1996) B 1 2 G sheet. O h t a has b e e n m o r e c o n c e r n e d w i t h the o l d e r r o c k s t h a n D a l l m a n n . H1 refers to H a r l a n d (1978), H 2 to H a r l a n d , H a m b r e y & W a d d a m s (1993) a n d H3 evolving to this w o r k . B, C & O adopted relatively fixist palaeogeology whereas H invoked significant displacement (e.g. along the Hansbreen Fault. Different traces for this were assumed in H1, H2, and H3. B, C, O & H all agree that the Isbjornhamna Gp is the oldest and with Paleoproterozoic, then Mesoproterozoic isotopic ages. O and H follow the C map as the best authority as to the outcrops of the many lithic units in this small but key area, and which supersedes the pioneer maps of B. But all differ in the interpreted sequence of strata.

196

CHAPTER 10

B

H1-2

Birkenmajer 1992

O

H3

Ohta & Dallmann 1992/1993

This work

C

Harland et al. 1993

Czerny et al. 1993

,

Sorkapp Land Group

S~rkapp Land Group

Sofiekammen Group

Sofiekammen Group

Sofiekammen Group

Sofiebogen Group G&shamna phyllite Fm

G&shamna phyllite Fm

H6ferpynten dst. Fm

Fannytoppen Ist Fm

Slyngf]ellet cgl. Fm

Fannypynten tUloid Fm Hansvika tilloid Fm

A

Deilegga Group Bergskardet Fm

E. of Hansbreen

Bergnova Fm Tonedalen Fm Eimfjellet Group Vimsodden Subgroup Jens Erikfjellet Fm Elveflya Fm

S~rkapp Land Group

Sofiekammnen Group 23-27

Sofiekammnen Group

Elveflya Fm (with dropstones)

G6shamna Fm (inc. 28 Dunderdalen Fm etc)

G~shamna Fm (incl. Tonedalen Fm)

H6ferpynten Fm 29-30

Fannytoppen Fm

Slyngfjellet Fm 31

Fannypynten Fm A

H6ferpynten Fm Jens Erikfjellet Fm

W. o f " - Hansbreen "--

Sorkapp Land Group

Hansvika Fm Jens Erikfjellet Fm 32

Slyngfjellet Fm

Slyngfjellet cgl. units Deilegga Subgroup Vimsodden Subgroup (Elveflya early tillite) A

Nottinghambukta Fm

[Bergskardet and Bergnova Fm] Eimfjellet Group Pytthomen Fm

Sk61fiellet Subgroup 33-38 Vimsodden Subgroup 39-45

Deilegga Group 55-57

E. of Hansbreen

Aust Torellbreen Group" \

Slyngfjellet units and Deilegga Fm

Elveflya Fm

A

Sk~l~ellet Fm

Sk&l~ellet Subgroup

?Dunoyane Fm ?Sk~lfjellet Subgroup

Steinvikskardet Fm Gulliksenfjellet

``

Jens Erikfjellet Fm

Gulliksen~ellet Fm Brattegggalen Fm

A

\ ` ` Magnethegda Group W. of `` Hansbreen

Deilegga Group Werenskioldbreen Group"- ...

G~shamna Fm

Eimfjellbreane Fm Skjerstranda Fm

Magnethegda Group 51

Eimfjellet Group

?Steinvikskardet Fm

Pytthomen Fm

Gulliksenf]ellet Fm

Gulliksen~ellet Fm Bratteggdalen Fm Sk&l~ellet Fm Eimfjellbreane Fm Skjerstranda Fm

Isbjernhamna Group

Isbjernhamna Group

Isbjernhamna Group

Isbjernhamna Group 52-54

Isbj~rnhamna Group

Revdalen Fm

Revdalen Fm

Revdalen Fm

Revdalen Fm

Revdalen Fm

Ariekammen Fm

Ariekammen Fm

Ariekammen Fm

Ariekammen Fm

Ariekammen Fm

Skodde~ellet

Skoddef]ellet

Skoddefjellet

Skoddefjellet

Skoddefjellet

Fig. 10.6. Comparison of stratigraphic schemes for southwest Spitsbergen as discussed in Section 10.9.1.

C maps a critical WNW-ESE nearly straight boundary line between their Isbjornhamna and their Eimfjellet Gp to the south and their Deilegga and younger groups to the north. This is the Vimsodden-Kosibapasset Fault (VKF) accepted by Balashov et al. (1995). It divides the Vimsodden Subgp of B whose lower units are included in the revised Eimfjellet Gp of C. The newly defined Eimfjellet Gp is accepted by H3. Thus C and H3 agree on the basement being Eimfjellet and Isbjornhamna groups. C interprets the (VKF) boundary between the Eimfjellet and Deilegga groups as a northward directed thrust, which it may well be; but H3 considers it also to mark a major unconformity. Overlying it H follows B in taking the oldest unit above the boundary to be formations of the Vimsodden Subgroup followed by the Deilgegga Gp into the Slyngfjellet Fm. H differs from B not as to the sequence but as to the age. H accepts the original Vimsodden tilloid (the Vimsa member of the Elveflya Fm of B) as Early Varanger tillite and most of the succeeding succession as Early Varanger including the Deilegga and Slyngfjellet units. This would break up the Eimfjellet Gp of B, and H3 proposes an Aust Torellbreen group to include this complex. Whereas H (and possibly B) consider the G~shamna F m (east of the Hansbreen Fault) as being late Vendian, C and O correlate it with the lower Deilegga unit and thence north to the Dunderbukta Fm which H is reasonably certain is intertillite, i.e. Early Varanger (Early Vendian) in age. This may be partly because O followed B in correlating the late or post tillite

Fannytoppen Formation as extending the H6ferpynten Fm. Thus O tend to assume that all pelites are GSshamna equivalents. On the other hand Krasil'shchikov (in Gramberg et al. 1990) would appear to support H in this respect. Referring to the Dunderbukta Formation of Krasil'shchikov & Kovoleva 1976 (which is the equivalent of the Dunderdalen Fm) he noted that the Deilegga Fm was a possible equivalent of this unit. B and O are agreed in making much of the Vendian succession of H much older. O follows C in arguing from the Slyngfjellet unconformity above the Deilegga rocks. O follows B in taking the Slyngfjellet Fm as preH6ferpynten Fm (which is probably Sturtian). From this it follows that the Deilegga and Vimsodden rocks would all probably be Mesoproterozoic. H would point out that the Slyngfjellet conglomerates occur also in mid Deilegga succession and could be a conglomeratic facies, nearly coeval. W i t h i n the area c o n c e r n e d (east o f H a n s b r e e n a n d s o u t h o f A u s t Torellbreen) the c u r r e n t l y available evidence is i n d e t e r m i n a t e . Nevertheless in this w o r k the s o l u t i o n here (H3) is suggested as the best fit to available d a t a a n d s t r e n g t h e n e d greatly by c o n s i d e r a t i o n s o f c o r r e l a t i o n elsewhere in Spitsbergen. W i t h o u t f u r t h e r discussion it is a d o p t e d in the c o r r e l a t i o n o f r o c k s t r e a t e d in this c h a p t e r in Fig. 10.7.

SOUTHWESTERN AND SOUTHERN SPITSBERGEN

Nordensk61dkysten

N.W. Wedel Jarlsberg S.W. Wedel Jarlsberg Land Land

Serkapp Land Group Sofiekammen Group Bogstranda Fm Fannytoppen Fm A Fannypynten Fm

o -s ?Ediacara Late Varanger

II III IIIII II III IIIIIIIII IIII Ill l Kapp Lyell Group A

Kapp Linn6 Fm 9 Linn~fjella unit

Konglomeratfjellet Group Aust Torellbreen Group Dunderbukta Fm Slyngfjellet and Deilegga fms Chamberlindalen Fm (B Gaimardtoppen Fm Jens Erikfjellet Fm (B) Fleykalven Fm / ~ Elveflya Fm Thiisfjellet Fm

Malmberget unit Early Varanger

L~gneset Fm (B) Gravsjeen Fm /~ L&gnesrabbane Fm Kapp Martin Fm

IIIIIIIIIII

E. Wedel Jarlsberg Land

III

Sturtian

MesoProterozoic

?Paleoproterozoic

q)

Duneyane Fm

Nordbukta Group Dordalen Fm Thiisdalen Fm Trinutane Fm Seljehaugfjellet Fm Botnedalen Fm Peder Kokkfjellet Fm Evafjellet Fm Kapp Berg Fm

Eimfjellet Group Pyttholmen Fm Gulliksenfjellet Fm Bratteggdalen Fm SkNfjellet Fm Eimfjellbreane Fm Skjerstranda Fm Isbjernhamna Group Revdalen Fm Ariekammen Fm Skoddefjellet Fm

197 S~rkapp Land Serkapp Land Group Sofiekammen Group G&shamna Fm

(unexposed unit)

Hansvika fm / ~

H6ferpynten Fm Quartzite Mbr Oolitic Ist Mbr Wurmbrandegga Mbr Andvika Mbr Kviveodden Mbr

J

Sigfredbogen Fm Magneth~gda Group

J Mefonntoppane units

IIII III Illlllllll

Lyngebreen sequence

ILIIIILIILIJlIILIIhll

Fig. 10.7. Correlation of Pre-Devonian units in southwest Spitsbergen as discussed in Section 10.9.1. Triangles are tillites; B indicates basic rocks; oblique slashes separate unconnected successions.

10.7.4

Mineralization

The only recorded occurrence of sulphide or other metallic minerals in Wedel Jarlsberg Land according to Flood et al. (1969) is at Revdalen where, within the Isbjernhamna and Eimfjellet Groups, Birkenmajer (1960) and Smulikowski (1965) recorded sulphidebearing quartz ankerite veins within amphibolite facies. Wojciechowski (1964) pointed out the sporadic occurrence of sulphides within the veins. The main minerals in Revdalen are pyrite, chalcopyrite, galena, sphalerite and pyrrhotite. Further details were given by Flood. However, the map of Czerny et al. 1992 plots a great number and variety of mineral occurrences between Torellbreen and Hansbreen in almost all formations. The occurrences include disseminated mineralization, concordant ore veins, discordant ore veins, laminated ores, nests and lenses of metasomatic ores, magmatic ultrmafic cummulate ores and pegmatite veins with the occurrence of minerals, each from the following list: pyrite, chalcopyrite, marcasite, sphalerite, galena, magnetite, hematite, imenite, pyrrotite, arsenopyrite, marcasite, cubanite, bornite, tetrahedrite, bournonite, boulangerite, bismuth, bismuthinite, proustite, antimonite, meckinawite, ankerite, dolomite, calcite, siderite, barite, fluorite, microcline, chlorite, epidote, actinolite, tourmaline and stilpnomelane. The problems of these and other mineralizations is addressed as a whole in the Appendix, because it cannot be assumed that they are Proterozoic, Paleozoic or Cenozoic.

10.8

Early Paleozoic and Proterozoic strata of Sorkapp Land

Sorkapp Land is a distinct geographical entity accessible mainly from Hornsund. Geological work has been largely achieved by the Norsk Polarinstitutt culminating in their 1 : 100 000 geological map C 13G (Winsnes, Birkenmajer, Dallmann, Hjelle & Salvigsen 1992) which conveniently covers just this area. The map description accompanying it by Dallmann, Birkenmajer, Hjelle, Merk, Ohta, Salvigsen & Winsnes (1993) is the definitive text. With a dominantly N N W - S S E strike the strata are arranged in broad belts with Van Mijenfjorden and Adventdalen groups in the east, Kapp Toscana and Sassendalen groups in a narrow strip down the centre flanked by Tempelfjorden, Gipsdalen and Billefjorden groups. Then a narrow strip of Precambrian rocks of unknown relationship. The western part of Sorkapp Land comprises a broad belt of 'Hecla Hoek' rock, in this case of Ordovician, Cambrian, and Neoproterozoic rocks flanked on the east by narrow outcrops of Devonian and on the west by flat-lying Early Carboniferous and Triassic strata.

10.8.1

Early Paleozoic strata

A break-through in Hecla Hoek stratigraphy was made by Winsnes (1955) in Major & Winsnes (1955) who established a carbonate

198

C H A P T E R 10

sequence w i t h the first r e c o r d e d O r d o v i c i a n a n d C a m b r i a n fossil finds in m a i n l a n d Spitsbergen. I n all 16 fossil localities were described f r o m scattered o u t c r o p s in c o m p l e x f o l d e d structures. This sequence, a p p r o x i m a t e l y overlying Late P r o t e r o z o i c rocks, was described as below, b u t is n o t seen in a n y o n e succession. W i t h the benefit o f w o r k i n g first n o r t h o f H o r n s u n d a n d later in S o r k a p p L a n d , B i r k e n m a j e r r e a r r a n g e d the s t r a t i g r a p h i c s c h e m e in t w o g r o u p s s e p a r a t e d by u n c o n f o r m i t i e s between, a b o v e a n d below. T h e S o r k a p p L a n d G r o u p was said to be O r d o v i c i a n a n d the S o f i e k a m m e n G r o u p C a m b r i a n . His scheme was t h u s unified for s o u t h Spitsbergen, i.e. for W e d e l Jarlsberg L a n d as well as for S o r k a p p L a n d . W e follow it here w i t h m i n o r m o d i f i c a t i o n s b u t d i s t i n g u i s h only the rocks f o u n d in S o r k a p p L a n d . T h e G r ~ k a l l e n Series o f M a j o r & W i n s n e s (1955) c o m b i n e d Tsjebysjovfjellet, R a s s t u p e t , N i g e r b r e e n a n d H o r n s t u l l o d d e n units as described b e l o w a n d n o t u s e d in this scheme.

Hornsund Supergp Sorkapp Land Gp, 1400+ m (Birkenmajer 1978) Arkfjellet sequence, 200+m. The formation underlies the Devonian unconformity, its base is not seen and its relationship to other units of the group is not clear. In places the succession was inverted before Devonian deposition. The succession appears to be: 70 m at the top of hard, black, quartzite and clayey shales, black oolitic limestone with fossil debris (brachiopods and corals) and grey limestone with laminated algal structures; 55 m dark shaly limestones and calcareous shales; thin conglomerate; 200+ m of folded and crenulated weathered silty shales with phyllitic textures, thin quartzite bands and 'uneven lumps of quartz'. An Ordovician age or younger is indicated by the poorly preserved fossil material. It therefore overlies the other formations of the Sorkapp Land Group or is equivalent to some. Birkenmajer suggested a possible correlation with some Hornstulloden subgp strata. Hornsundtind (limestone) Fm, 500m (Birkenmajer 1978) (relationship not clear). Sjdanovfjellet (limestone) Unit was described by Major & Winsnes with a Late Canadian fauna: g a s t r o p o d s - Hormotoma, Maclurea and Straparollina; nautiloids: Onetoceras loculosum, Beekmantoceras priscum, Bathmoceras, Polygrammoceras. It may be the equivalent of the upper part of the Tsjebysjovfjellet Mbr or a third higher member. Tsjebysjovfjellet (limestone) Mbr, 4 0 0 + m of light grey to black slightly bituminous limestone with some dolomitisation or silicification. Both members may show fine lamination or phyllitization. Rasstupet (limestone) Mbr, 80 m of pinkish- or brownish grey thick bedded limestone. With Late Canadian fauna including gastropod: Maclurea; brachiopod, Diaphelasma; sponge, Receptaculites; nautiloids, Protocycloceras cf. lamarki, Vaginoceras. Nigerbreen (limestone) Fm 80 to 120m of black or grey banded limestone with black chert lenses and dolomitization and a Canadian fauna: gastropods, Ceratopea and Maclurea; nautiloid; Vaginoceras cf. longissimurn Hornstullodden Subgp. This unit, originally a formation, is retained from Major & Winsnes (1955) with three limestone divisions) which, (1) to (3), approximate to Birkenmajer's three formations and none with recorded fossils. (3) Dusken (limestone) Fro, 20 30 m (name from Wedel Jarlsberg Land, (Birkenmajer 1978) is of thin-bedded laminated limestones, grey to black alternating with yellowish laminae and puncuated by irregular cherts. (2) Luciapynten (dolostone) Fro, 100m of varied coloured dolostone passing into dolomitic sandstone and with occasional breccias. (1) Wiederfjellet (quartzite) Fro, 300m is best developed in Wedel Jarlsberg Land with two members. Goi~sbreen Mbr, 270m is the upper member best developed in Sorkapp Land. It is of dark grey to black arenaceous carbonates alternating with sedimentary breccias. Paierlbreeen Mbr appears to be limited to Wedel Jarlsberg Land. The Wiederfjellet Fm oversteps unconformably different units of the underlying Sofiekammen Group. Sofiekammen Gp (max 935 m) in Wedel Jarlsberg Land. The name (Birkenmajer 1958, 1978) is taken from the mountain in Wedel Jarlsberg Land. The Group is predominantly dolostone and limestone with shale and sandstone lower down and of variable facies. The thickness is somewhat less in Sorkapp Land. Nordstetinden (dolostone) Fm (Birkenmajer 1958, 1978) 150m in Wedel Jarlsberg Land with two members.

Nordstebreen Mbr, 50 m of platy dark grey or black dolostone in bands 1 to 10 cm thick alternating with yellow mainly dolostone. Lingulellaferringinea has been recorded.

Hansbreen Mbr, 100m of light or dark grey to bluish massive dolostone, sometimes laminated, with black chert or alternates with dark bituminous laminated dolostone. No fossils were recorded. Gn~lberget (marble) Fro, 200 m (Birkenmajer 1959). This is a massive calcmarble, limestone, and dolomitic limestone with some pink calcite and red jasper veins. No fossils were recorded. It mainly occurs in Wedel Jarlsberg Land with minor occurrences only in Sorkapp Land. Slaldi Subgp. Major & Winsnes (1955) introduced the name Slakli Series for the rocks described below as the Slaklidalen and Vardepiggen formations. This name, familiar in the literature, may be worth preserving as a subgroup. Slaklidalen (limestone) Fro, to 120 m (Birkenmajer 1978). This is unit (1) of Major & Winsnes Slakli Series. It is black to grey limestone, sometimes dolomitic, bituminous or arenaceous with Olenellus cf. thompsoni, Senodiscus bellimarginatus, S. cf. speciosus, Calodiscus lobatus, Pagetia, Hyolithellus cf micans, Hyolythes, Platyceras primaevum, Obolella cf. atlantica. ( : BonniaOlenellus zone of Fritz 1972) of late but not latest Early Cambrian age. Vardepiggen Fro, 420-450 m in Sorkapp Land (formation and member names are from Wedel Jarlsberg Land (Birkenmajer 1978). Flogtoppane Mbr, 10m is of black to grey, often graphitic shales, some sedimentary breccias. Midifjellet Mbr, 20m is similar to Slaklidalen Limestone (no recorded fossils) Olenellusbreen Mbr, 300-350 m is of green to black shale with sedimentary breccias 2 10 m thick with clasts of dolostone, limestone and (G~tshamnatype) phyllite; Olenellid trubolites Nevadella sp., Olenellus svalbardensis. This is the 'Olenellus shale' in the lower part of the Slakli Series of Major & Winsnes (1955). Blfistertoppen (dolostoue) Fro, 95+ m Russepasset Mbr, 25+ m is of black or blue, yellow weathered arenaceous dolostone. Flakfjellet Mbr, 35m of black shale with thin grey limestone and concretions, with Olenellus svalbardenis, O. sculptilis G~sbreen Mbr, 35m is of pure dolostone and dolomitic limestone above yellow arenaceous dolostone below. The basal unconformity was said to be in angular contact with the GAshamna phyllite Formation (see below). However, the section at Slaklidalen to Wiederfjellet (Birkenmajer 1978, fig 15, p. 20) suggests a concordant relationship.

10.8.2

Neoproterozoic strata

Sofiebogen Gp G~shamna Fro, 1.5 km (Winsnes 1955), c. 3 km (Birkenmajer 1992). As described above the lithologies of the Bogstranda unit are similar with dominant green to black (some graphitic) phyllites with intercalated quartzite shale units which may cut through 2kin to the south at Slaklidalen, the top being truncated by Cambrian strata suggesting that an upper 1 km of phyllites may be missing there. Beds of dolostone but not limestone occur. Interbeds are generally persistent over a km or more. Upper division, c. 500 m is of black shales and phyllites exposed near shore. Middle division crops out south of G~sbreen. Lower division is variable with green and grey slate and phyllite; probably equivalent to the lower part of the Bogstranda Fm. The lower boundary is tectonic as first pointed out by Winsnes (1965) and confirmed by CSE in 1977 Hiiferpynten Fm (Winsnes 1955). The formation is superbly well exposed at the eponymous promontory and is divided as below. Winsnes (1955) showed the unit to be thrust over the G~shamna Fm and not in a sedimentary succession. He described it in three parts (3) quartzites, (2) limestone with oolites and (1) dolostones with cherts. It is now divided into six members (Birkenmajer 1972). (6) Quartzite Mbr, 300+ m three prominent ribs of quartzite surounded by phyllite (at sea level) appeared to be conformable with the older strata to the author (Harland 1978) as to Winsnes whereas Birkenmajer has included these rocks in the G~tshamna Formation. Exposure is poor to the east. (5) Oofific Limestone Mbr, 40 m with a conspicuous stromatolite bed at the top. Grey limestone with oolite (Winsnes 1955) and pale-weathering dolomitic oolite and pisolite (Birkenmajer 1972, 1977 and named his Dunoyane Mbr).

SOUTHWESTERN AND SOUTHERN SPITSBERGEN (4) Wurmbrandegga Mbr, 300 m is a massive grey dolostone with occasional current bedding, lacking cherts. (3) Andvika Mbr, 300 m is the lower part of Winsnes' dolostone: it contains grey chert layers which are more continuous near the top. (2) KvivoddenMbr: Upper division, (20 m), is a complex of grey-greenish and yellowish dolostone, distinguished by Birkenmajer as his Fannytoppen Mbr. (1) KvivoddenMbr: Lower division, (10 m), is of deformed lenticular yellow and reddish quartzite pebbles and boulders (2 to 20 cm) within a matrix of deformed quartzite phyllite and interpreted as a silicified intraformational conglomerate, possibly first dolomitized. Harland 0978) incorrectly thought that this was mapped by Birkenmajer (1960) as the Slyngfjellet Conglomerate which unit was identified with apologies as the Sigfredbogen Fm (Harland, Hambrey & Waddams 1993). Sigfredbogen Fro, >300m. This unit was named (Harland et al. 1993) for the highly sheared quartzite-metapsammite forma~tion. It is exposed along the shore west of H6ferpynten and striking N-S with about 10m of metaconglomerate at the eastern end of the outcrop exposed in a small onshore depression. It was concluded that the the psephite and the psammite were joined in a continuous unit, the conglomerate being a local development of the quartzose rock. The psephite was referred to by Birkenmajer (1960, 1972) as his Slyngfjellet Conglomerate (at the eastern end), the psammite as the Bergskardet Fm of the Deilegga Group. However, both facies seemed to differ from those two formations north of Hornsund in both composition and in their higher metamorphic grade. This correlation is doubted and, on the evidence available, no other correlation is offered. If the postulated Kongsfjorden-Hansbreen Fault Zone (Harland, Hambrey & Waddams 1993) is a terrane boundary then the Sigfredbogen Formation would lie to the west of it and so belong to the Western Terrane. The correlation might thus be sought within the Isbjornhamna Group e.g. the Ariekammen Fm. But, because it is probably bounded by faults on east and west sides, and if these are N-S splays of the fault zone, then the Sigfredbogen Fm could have moved to its present position relative to the Isbjornhamna Group from further south.

Other older rocks of Sorkapp Land. There is a strip of older rocks extending south east of Samarinv~gen in Hornsund to Kistefjellet at the southern tip of Sorkapp Land. They were less metamorphosed and tightly folded beneath the Devonian and Carboniferous strata. The 1:100 000 map, C13G (Winsnes e t al. 1992) shows five rock types (map units 34-38). Although in one single belt extending 40 km N - S and 1-7 k m across the outcrops appear as two distinct associations. The northern two thirds of the outcrop belt is occupied by two facies mainly quartzite and garnet schist (map unit 38) in contact (without marked faults) with marble (unit 37), with unit 37 apparantly above unit 38. Each formation is probably at least 1 km thick. These are referred to as Mefonntoppene rocks. Dallmann et al. (1993, p. 18) compared the garnet mica schists with the Skoddefjellet Fm and the marbles with the Ariekammen Fm both of the Isbjornhamna Group north of Hornsund and thought to be at least 970 Ma old (Birkenmajer 1993) or older (Balashov et al. 1995). In addition to the above correlations similarities between some Mefonntoppane rocks and the Gulliksenfjellet and Steinvikskardet fms above the Isbjornhamna Group were suggested. The southern outcrop is less obscured by ice and shows a consistent sequence on the map around the flanks of Kistefjellet referred to here as the Lyngebreen sequence as below: carbonate (unit 34), 1+ km, quartzite (unit 36), 100-200 m phyllite and mica schist with garnets (unit 35) phyllite and mica schist (unit 35), c. 2 km. The carbonate, unit 34, appears in an isolated nunatak (Breskilknausen) between the Mefonntoppene rocks and those at Kistefjellet where the same unit is well developed. Birkenmajer (1993) compared this with the H6ferpynten Formation. These appear in a pre-Triassic anticline plunging NNW. Both rock groups are covered mainly by Triassic strata except at one locality in the centre where Adriabukta rocks (Early Carboniferous) intervene. Long N-S thrust faults bound the strip on each side. To the west the Sorkapp Land Group (Ordovician) strata down to the Hrferpynten Formation (? Late Riphean) are generally uncovered except by Marietoppen (Devonian) strata in the northeast, by scattered Triassic strata generally and by Early Carboniferous rocks in the west.

10.8.3

199

Minerafization around Andvika

Wojciechowski (1964), Birkenmajer & Wojciechowski (1964) and Flood (1969) reported sulphide occurrences at Andvika which are opposite the extensive occurrences north of Hornsund. They are associated with faults and associated sheared breccia zones within the dolomitic facies of the H6ferpynten Formation and have never tempted exploitation. Ankerite and siderite occur as general impregnations whereas the distinctive veins with quartz gangue and geodes are characterized by the sulphides, pyrite, arsenopyrite, sphalerite, galena and chalcopyrite.

10.9

Correlation of pre-Devonian through S W Spitsbergen

With the exception of the Early Cambrian and Early Ordovician strata of eastern Wedel Jarlsberg Land and Sorkapp Land the extensive Precambrian rocks have not yielded determinable fossils to aid correlation. The only significant isotopic ages from the sector are those from the Eimfjellet and Isbjornhamna groups which identify these as Mesoproterozoic. A major correlation tool for Proterozoic correlation has been the two Varanger glacial horizons and the presence of associated basic volcanics with the earlier one. Otherwise we are left with the uncertainties of lithological correlation in a terrane which has undergone at least two orogenic episodes. The difficulties in establishing an agreed sequence have been demonstrated for southwest Wedel Jarlsberg Land (Section 10.7.3). This work attempts to give at least one coherent solution (Fig. 10.7). A major terrane boundary is postulated to trend through Recherchefjorden, Recherchebreen and south to Hansbreen with a possible splay out through Torellbreen (the KHFZ).

Western terranes.

To the west of this postulated KongsfjordenHansbreen Fault are the western terranes which, south of Isfjorden, are entirely Precambrian with one possible exception. The major outcrop area of this has been argued to be of Varanger age i.e. including the two tillite horizons and the strata between. The tillites may be distinguished by their stone content, the later one being characterized by extra-basinal crystalline rocks often distinguished by colour. The earlier tillite is dominated by intrabasinal clasts (stones and matrix) generally softer and less conspicuous. The earlier Varanger rocks are typically associated with basic volcanics. The whole Varanger sequence reflects a tectonically mobile environment with erosion of tills forming conglomerates, with strong current indicators and thicknesses commonly around 10 kin. In Fig. 10.7 columns 1-3 are western terranes. In northwestern Wedel Jarlsberg Land are the (lower) Varanger Konglomeratodden Group and the (upper) Kapp Lyell Group; in the southwest only the equivalent of the lower group is represented by the (newly designated) Aust Torellbreen Group. Where the succession beneath the lower tillite is exposed in each case only thin strata are seen above a major unconformity. In northwestern Wedel Jarlsberg Land this truncates recumbently folded formations of the N o r d b u k t a Group. In the southwest Wedel Jarlsberg Land a faulted unconformity truncates an apparently concordant sequence of Eimfjellet overlying Isbjornhamna Group formations. Both these groups have yielded isotopic ages with a thermal event at c. 950 Ma with igneous strata 1100-1200 Ma old and with indications of some rocks being up to 2200 or 2500 Ma (Balashov e t al. 1995, 1996b). These two half windows show what must be a complex proto-basement in which the exposures have little in common. Possibly between the Vendian and proto-basement would be the Dunoyane Formation (?Sturtian) exposed in offshore islands. The western terranes are all associated with mineralization.

Central terranes.

East of the K H F Z the strata range downwards through Early Ordovician, Early Cambrian, probably Ediacaran phyllites (up to 2500m) and two Varanger glacials (totalling

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1500 m), no volcanics, and minimal mineralization. The K H F Z not only truncates the lower tilloid north of Hornsund, but also the H6ferpynten Formation to the south which, with its characteristic stromatolite and oolitic facies, could be Sturtian in age. To the north of Wedel Jarlsberg Land and east of the postulated fault at Recherchefjorden is the Magnethogda gneissic unit which would seem to be a further and distinct proto-basement unit. The Magnethogda sequence was mapped as units 49 down to 55 in Sheet B11G (Dallmann et al. 1990). However, as they now realise from mapping of the adjacent sheet B12G (Ohta & Dallmann) to the south, that the Ggtshamna Formation (unit 28) to the south overlaps with unit 55 to the north, which at least inverts the sequence to the north - the Magnethogda rocks being undoubtedly older. Thus units 53 and 55, and possibly also 52, could be Vendian, whereas 49 and probably 50 are almost certainly pre-Vendian. A problem remains with the interpretation of the mountain tract between Aust and Vest Torellbreen which has only been reconnoitred. Birkenmajer et al. (1992) reported at Krakkow 'anthracite' similar to the meta-bituminous vugs in the H6ferpynten Formation. Ohta (pers. comm.) reported a possible Cambrian fossil. This sub-terrane may be displaced by faults. Apart from the Magnethogda rocks, mineralization is minimal. Whereas Silurian Caledonian deformation has not been established in the western terranes it is evident as the main episode deforming the Precambrian strata in the inner Hornsund region. The Kongsfjorden-Hansbreen Fault, as a major postulated lineament, possibly an outcome of Caledonian tectonism with sinistral strike-slip completed in Late Devonian time, is generally obscured by ice, water or post-Devonian strata. Sinistral shear structures are seen just west of Hansvika, at least two fault splays are mappable just west to H6ferpynten and south of Magnethogda a mylonitic gneiss is mapped along the possible fault trace. However, there may well be one or more splays out to sea via Torellbreen (as was first thought by Harland & Wright, 1997). In conclusion, there are difficulties yet to be resolved with the above hypothesis. Some could be decisive enough to require a reformulation. Other hypotheses, or nul hypotheses without major strike-slip displacements, seem to the author to encounter greater difficulties. Time will tell and this work is to advance understanding by formulating fallible hypotheses as a challenge.

10.10

Structure of western Nordenski61d Land

Nordenski61d Land exposes the main body of the Central Basin with its Paleogene coalfields. Its western margin comprises two distinct terranes which are parts of the West Spitsbergen Orogen where it is relatively narrow. Bordering the western edge of the Central Basin with relatively flat-lying strata is an abrupt transition to the distinctive fold and thrust belt which deforms Carboniferous through Early Paleocene strata. This is a mountainous zone of visibly complex structures. West of it is the other terrane of Proterozoic basement. It is a low-lying area of slight relief forming an extensive strandflat known as Nordenski61dkysten. To interpret the structure of the basement, whose outcrops are seen mainly in plan, depends on a knowledge of the stratal succession and this has received relatively little attention. The two 1:100 000 map sheets (B9G, Ohta et al. 1992 and B10G, Hjelle et al. 1986) gave one stratigraphic interpretation. Another by Harland et al. (1993) postulated the whole succession from the upper tillite in the north to the lower tillites in the south to be of Varanger age. Narrow faulted inliers of Carboniferous conglomerates and sandstones are conspicuous. Less evident, perhaps is a postulated thrust to the N E trending N W - S E as shown on the map by Harland et al. Clearly many other structures remain to be elucidated. The eastern boundary is well marked by the pale-coloured conglomerates of the cover rocks above the basal Carboniferous unconformity. The unconformity generally dips E in the foothills and demonstrates that the low-lying basement had risen to at least a similar height as the fold belt and appeared to have provided the impetus for the eastward compressive thrusts and folds.

Croxton & Pickton (1976) reported that the extreme western limb of the Paleogene basin with a N W - S E axis is bounded by the fold and thrust belts of the West Spitsbergen Orogen (trends NNW-SSE). Paleogene strata dip steeply to the E and NE, but shallow rapidly eastwards. Around Kolfjellet the strike swings from N N W - S S E to N W - S E with dips up to 20 ~ Their structure contour map of the base of the Firkanten Formation shows this swing and minor normal faults also throw strata down to the east. The underlying Carolinefjellet Formation is not so easy to map structurally, but the Helvetiafjellet Formation below is concordant with the Paleogene structures above. The fold belt is conspicuous and has long been known especially from its E - W cliff sections which truncate the north and south of the belt where cut by Isfjorden and Bellsund respectively. It is also easily accessible from Gronfjorden in the east. The northern cliffs have been described many times most notably in the classic Festningen profile of Hoel & Orvin (1937) where, with steep dips and strikes broadly perpendicular to cliff sections, the standard succession of cover rocks was established with detailed measurements and descriptions (Fig. 4.1.1). With the regular succession in mind the structure was first visualized as a monocline forming the steep to vertical western limb of the Paleogene syncline of the Central Basin (Orvin 1940). However with greater appreciation of the West Spitsbergen Orogen, and this a key part of it, thrusts were identified with other complications in the structure. As part of the CSE programme of E - W traverses a first indication of the nature of the fold belt was evident in A. Challinor's serial sections (made between 1960 and 1969) - a selection of which, through the entire orogen, are first published in this volume in Chapter 20, and include the Nordenski61d Land sector. The structures have invited much attention in recent years. They are easily seen in the mountain cliffs by the lithologies of the strata of the cover rocks notably the Permian Kapp Starostin, palecoloured resistant and competent, marker horizon contrasting with the overlying dark, soft, incompetent siltstones and shales of the Sassendalen Group. The first comprehensive map with cross-sections for the whole belt between Isfjorden and Bellsund was by Maher, Ringset & Dallmann (1989) with eight serial W S W - E N E cross sections, superficially endorsing Orvin's monocline, but with many complications. The section depicted the observed structure in the mountains. A more sophisticated study of the same belt by Braathen, Bergh & Maher (1995) extrapolated the structural logic to the great depth and height (Fig. 10.8). They also attempted a N - S section which is equally complex. This shows a consistent northerly vergence of the thrusts which is consistent with the dextral transpression hypothesis. An interpretation of the required deformation stages was attempted (five at Festningen and four at Bellsund) to result in the postulated structure. A study of Kongressdalen in 1996 showed a SW verging thrust (D. Paton pers. comm.) Most of the details that follow are based on those two papers. It may, however, be generalized that all the structures interpreted by all parties endorse thick- rather than thin-skinned tectonics. This contrasts with the much wider belt north of Isfjorden where the deeper thrusting in thicker strata in the west pushes the strata on d6collement zones into the typical thin-skinned structures over the Nordfjorden Block. At this latitude the Central Basin takes the place of the Nordfjorden Block, the d6collement thrusting passed beneath the mildly folded Paleogene strata and probably occupies the same d6collement zones so as to surface in the older N - S fault zones still further east.

10.10.1

Eastern margin of the fold belt

In the north the transition between the fold belt and the Central Basin is obscured by Gronfjorden. The fjord appears to be eroded into a broad symmetrical anticline with a core of less resistant Jurassic-Cretaceous shales. To the west at Festningen the vertical Cretaceous sandstones with a sliver of Palaeocene Firkanten

SOUTHWESTERN AND SOUTHERN SPITSBERGEN

201

Formation are folded into a tight syncline seen in the northwest coast of Gronfjorden. The eastern flank of the anticline on the east coast of Gronfjorden is of generally easterly dipping Cretaceous sandstones overlain by the coal-bearing Firkanten Formation, mined at Barentsburg. This zone of softer Triassic, Jurassic and Cretaceous strata continues south and divides. In the west is the low-lying glacial cover of Gronfjordenbreane and into Fridtjovbreen and the large natural harbour of Fridtjovhamna. East of this is a ridge of steeply folded Triassic through to the low ground of Berzeliusdalen (with its deep well) underlain by Cretaceous strata and into the low easterly dips at the west of the Central Basin at an old coal working in the Firkanten Formation at Camp Morton.

The structures on Midterhuken can be attributed to the development of a foreland prograding fold- and thrust-belt characterized by east-vergent thrusting in Late Eocene time (Maher et al. 1986, 1988; Ringset 1988). The undeformed strata in the Midterhuken foreland dip 20 ~ towards the east as part of the west limb of the broad Central Spitsbergen Basin. Basement rocks become involved in Tertiary deformation about 8 km to the west even though about 3 km of platform strata are involved. In contrast to most fold-and-thrust belts, stratigraphic repetition occurs along only one Midterhuken fault. In addition, there is little evidence for typical ramp-flat staircase thrust geometry (Maher et al. 1986). Mann (CASP) from eigenvector analysis of the Janusfjellet folds suggested a dextral shear in a N-S-oriented shear zone.

10.10.2

10.12

Main fold belt

The high mountains identify the main fold belt of stratal thickness of about 3 km with the steepest dips. It varies in width from 4 km E-W in the south to 7 km in the north with a N-S length of 40 km. Easterly dips increase from 30 ~ in the W to vertical in the centre and east. Later than Challinor's foray in the early 1960s is the work of Maher et al. (1989), Braathen & Bergh (1995) and Braathen, Bergh & Maher (1995) (Fig. 10.8), Ohta (1988), Kimura, Ohta & Nakamura (1990) and other studies included in the synthesis by Dallmann, Andresen et al. (1993). In the Festningen section Permian to mid-Triassic formations dip east at about 30~ to 50 ~ and later Triassic to Paleocene strata dip 70 ~ to 90 ~ Balanced cross-sections from work by CSE/CASP Townsend & Mann indicated an E-W shortening of 3.25-3.5 km. In addition to truncation of strata by thrusts, Challinor noted that the top of the Vegardfjella Formation and the lowest units of the Gipsdalen Group have been cut out only by a basal Permian unconformity, so that Wordiekammen Formation lies directly on Billefjorden Group clastics. These Permian strata are folded into a series of inclined folds with wave lengths 250 500 m and verging westwards. In the Bellsund sections Botneheia shales, with minor N N W SSE-trending folds, transect cleavages indicating a dextral shear sense. The Janusfjellet Formation forms a detachment and accommodation zone between the Kapp Toscana sandstones and the Helvetiafjellet sandstones. Cambridge geologists including WBH have reconnoitred the area but their results do not contradict what has been published. The structure of this segment of the fold belt is illustrated in Fig. 10.8. The structure is well displayed by the conspicuous outcrops of the competent Kapp Starostin Formation, which underlies the incompetent Sassendalen Group strata, and in turn by the competent Kapp Toscana Group strata. Recent seismic and structural studies (Faleide et al. 1988; Andresen et al. 1988; Bergh et al. 1988; Haremo & Andresen 1988) imply that basement overthrusts occur in the subsurface of Nordenski61d Land (e.g. Ohta 1988). These structures would be necessary for the lateral continuity of the thrust system further east.

10.11

The Structure of western Nathorst Land

Midterhuken is the western tip of Nathorst Land where the two fjords Van Mijenfjorden and Van Keulenfjorden converge to form the wide fjord of Bellsund. To the north is the long straight N-S island, Akseloya, which almost connects the Kapp Starostin Formation with Nordenski61d Land to the north. The structure can be seen well in the cliffs from the sea and is one of the most photographed structural features in Svalbard. It was described by Maher et al. (1986) with seven structural zones west to east (ST 1-7). They are based on the differences in structural response by the various stratigraphic units, in addition to the major fault surfaces. They are illustrated in Fig. 10.9.

The structure of Wedel Jarlsberg Land

Wedel jarlsberg Land is intermediate between the lands to the north and those to the south geologically as well as geographically. From east to west four zones are recognized: (a) the Central Basin Paleogene and Cretaceous outcrops narrow southwards with a western margin which trends NW-SE to NNW-SSE; (b) the West Spitsbergen Orogen Fold belt to the west runs parallel from western Van Keulenfjorden to inner Hornsund; (c) the Hornsund-Sorkapp Basement extends east of Recherchefjorden in the north and Hansbreen; (d) west to the coast is the western basement (Coastal Horst of Harland 1989). The boundary between (a) and (b) is transitional westwards into more intense folding which is certainly of Paleogene age. The boundary between (b) and (c) is less easy to assess. Almost certainly the (Marietoppen Formation) Devonian strata with eastward verging folds and thrusts belong to the Paleogene fold belt (Fig. 10.10). The Hornsund-Sorkapp Basement (c) to the west a basement high exhibits Late Proterozoic to Ordovician strata dipping steeply west and younging eastwards. It is clear from similar structures south of Hornsund that they are pre-Triassic and typically Caledonian from which Devonian conglomerates derived possibly along a boundary fault zone (Gjelberg & Steel 1981). These were admirably depicted in the profiles north and south of Hornsund by Birkenmajer (1960) (redrawn in Fig. 10.10). Within this complex to the north is a probable Proterozoic Basement unit in the Magnehogda rocks. These are highly deformed metamorphosed gneisses in close proximity to metamorphosed CambrianOrdovician strata. It has yet to be isotopically investigated. The Coastal Horst (d) in Wedel Jarlsberg Land has no Phanerozoic strata to constrain the age of deformation excepting the Calypsobyen half graben of Late Eocene to Early Oligocene strata which help little because the main West Spitsbergen Orogeny climaxed in mid-Eocene time. However, the Coastal Horst contains two major structural units which may well be related structurally if not by age. They are (i) the proto-basement of the Nordbukta Group, deformed in recumbent folds and incontravertably unconformably overlain by (Early Varanger) tilloids and (ii) the proto-basement of the Isbjornhamna and Eimfjellet (sensu Czerny et al. 1992) groups with a postulated unconformable tilloid cover, as argued in Section 10.9 above, and with a Paleo- to Neoproterozoic thermal record. It is suggested here that the whole Coastal Horst (proto-basement and Vendian cover) may have suffered some ?Ordovician tectonothermal event, but was mainly a western zone of the Paleogene orogeny.

10.12.1

Structure of the West Spitsbergen Orogen

The latest (Paleogene) Spitsbergian deformation structures are the most conspicuous. The northern transect' south of Van Keulenfjorden has been investigated in some detail (the work of R6zycki 1959, Dallmann 1988a, b and Dallmann et al. 1993). The middle of Wedel Jarlsberg Land to a less extent and the southern outcrops were reconnoitered, but not subjected to similar analysis.

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Fig. 10.8. Structural map and representative cross-sections of Nordenski61d Land, illustrating the structure of Carboniferous to Cretaceous units. Simplified and redrawn from figures in Braathen, Bergh & Maher (1995), with permission. The dotted line markes the ice-rock boundary.

SOUTHWESTERN AND SOUTHERN SPITSBERGEN

203

Fig. 10.9. Simplified structural profile across the Midterhuken Peninsula (after Maher, Craddock & Maher 1986). The northern transect. T h e Berzeliustinden area is located at the o u t c r o p b o u n d a r y between the largely m e t a m o r p h i c H o r s u n d S o r k a p p Basement sequences and the overlying cover sediments o f C a r b o n i f e r o u s to Tertiary age. To the west of this b o u n d a r y , cover rocks preserved on the d o w n - f a u l t e d block at R e i n o d d e n and at R e n a r d o d d e n show that C a r b o n i f e r o u s - P e r m i a n strata extended further west prior to extension in this area ( D a l l m a n n 1988a, 1989). The structure of the Berzeliustinden area has been discussed by a n u m b e r of authors (R6zycki 1959; D a l l m a n n 1988a, b 1989). A lithological a n d stratigraphic s u m m a r y for the late Paleozoic to Cretaceous successions in the area was given by R6zycki (1959). The extensional structures in the area post-date the West Spitsbergen O r o g e n y ( H a r l a n d 1969, 1985; B i r k e n m a j e r 1972).

Dallmann (1988a, b, 1990) divided the area into two main structural units separated by the Berzeliustinden Thrust Fault (BTF), which has an approximate ENE vergence and displacement of about 800 m. The amount of displacement along the BTF has been estimated to be 2 km by Hauser (1982), which approximates with the value obtained if the displacement accommodated by folding in both the upper and lower

tectonic unit is added to the displacement of 800 m along the BTF, projected into the true plane of displacement, giving a total displacement of 1.5 km (Dallmann 1988b). Dallmann (1988a, b) showed that movement on the Foldaksla Thrust Fault (FTF) and d~collement zone caused repetition of part of the succession without stratigraphical inversion. On a west to east profile, sandstones of the Wilhelmoya Formation and Brentskardhaugen Bed are overlain by black shales of the Botneheia Formation; both the Botneheia Formation and the Kapp Toscana Group are structurally repeated and interpreted as a backthrust in front of the Berzeliustinden thrust unit. Formation of the Berzeliustinden structure. Dallmann (1988a, b) inferred a sequence of events for the development of the Berzeliustinden structure based on a thrust wedge propagation model. (1) Uplift of the basement antiform to the west followed by mechanical failure and eastward thrusting along the Berzeliustinden Thrust Fault. The fault may initially have continued into the Botneheia Formation black shale. (2) The development of a backthrust cutting the Botneheia Formation sandstone and the Kapp Toscana Group, giving rise to a ramp structure from the lower Botneheia to the upper Janusfjellet black shale formation.

Fig. 10.10. Schematic structural profiles of northern Sorkapp Land and of southern Wedel Jarlsberg Land (adapted from Birkenmajer 1960 so that both profiles are drawn as interpreted from the south).

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(3) A d6collement zone developed within the Botneheia Formation shale causing the formation of detachment folds in the repeated sequence between the shale formations. The interaction of backthrusting and gravity glide may have provided a mechanism for the generation of eastward and west-vergent structures. (4) The regional folding of the whole area initially generated the basement antiform, but may have continued during or subsequent to the main thrusting event. The low angle of the BTF and the steep orientation of the backthrusts implies eastward rotation and may be explained by regional folding. The geometrical configuration, resulting from the regional folding, permitted further propagation of the thrust wedge. (5) Subsequent thrusting along the BTF was accommodated by faultpropagation folds (i.e. tip-line structures) in the strata in front of the former wedge. Thin-skinned deformation within the Janusfjellet black shales, aided by low shear strength, formed east-vergent thrust systems in the continuation of the BTF and a backthrust at the boundary to the overlying Helvetiafjellet sandstones. The estimated displacement on the BTF of almost 1.5 km is partly accommodated by deformation in the overlying sedimentary cover.

conglomerates and basic volcanics. The terrane to the west is locally rich in a variety of sulphide minerals in contrast to the east. In line with the supposed boundary a N - S mylonitic outcrop is mapped (Ohta & Dallmann 1992) across north of Profilbreen. At Baranowskiodden, immediately west of the glacier cliffs of Hansbreen, which is postulated to conceal the KongsfjordenHansbreen Fault Zone, are clear indications of sinistral shear in a N - S direction. To the east of the promentory are indicators of strata with sinistral strike-slip faults and deformatiom. To the west in the Steinsvikskardet Formation, Birkenmajer (1992, p. 21) depicted a complex of tight folds cut by N - S sinistral faults, similarly at Wilkczeodden, southwest of Isbjornhamna. These structures could represent an initial strike-slip (transpression zone) in the Silurian Caledonian Orogen and end with final Late Devonian docking of the central with the western province.

10.12.3 A middle transect: the structure of the Supanberget area. The Supanberget area is located in the interior of Wedel Jarlsberg Land about 20 km to the south of Van Keulenfjorden, and forms part of the central NW-SE-trending ridge that separates the pre-Carboniferous basement in the southwest from the Late Paleozoic strata in the northeast. The stratigraphic succession of the area is based on the work of R6zycki (1959), Bjornerud (1990), Steel & Worsley (1984) and Nys~ether (1977), and the basement sequences have been reviewed by Harland (1978), Flood et al., Sheet 1G (1971) and more recently by Bjornerud (1987, 1990). Within the Supanberget area, the pre-Carboniferous basement, referred to as Caledonian basement by Dallmann & Maher (1989a, b), comprises the Magnethogda sequence or group (Harland 1978, 1985; Bj ornerud 1990) of possible Mid-Proterozoic age (Flood et al. 1971). The Supanberget Thrust System can be divided into a western zone characterized by significant basement involvement, and an eastern (foreland) zone characterized by high level tectonism (Dallmann & Maher 1989a, b). The minimum estimate of shortening within the Zittelberget--Engadinerberget area, determined using the shortening accommodated by the fold structures above the thrust, is about 500 750 m and must represent the sum of the transport along thrusts and also the shortening by drag folds beneath the thrust. The presence of bedding-parallel thrusts (i.e. detachments) or backthrusts in the foreland area, particularly in the northern part, suggests a much greater amount of shortening especially if such thrusts occurred at deeper levels (Dallmann 1988a, b). In the area between Supanberget and Stanislawskikammen the shortening by thrusting is estimated to be about 1 km with an additional amount accommodated by drag folding.

10.12.2

Postulated Silurian-Devonian strike-slip faulting

The boundary between central and western provinces of Svalbard of Harland & Wright (1979) followed a trace through Recherchefjorden, Recherchebreen in the north and through Hansbreen in the south ofWedel Jarlsberg Land as revised by Harland, Hambrey & Waddams (1993). The terrane boundary has been argued on evidence outside this land, but only evidence from Wedel Jarlsberg Land will be noted here. Correlation of the formations in the eastern and western limbs of the Kapp Lyell syncline is secure by mapping. However, the underlying proto-basement (the Nordbukta Group), which is relatively unmetamorphosed, contrasts with the Magnethogda gneisses to the east of the supposed boundary. The post-proto-basement strata succession to the east of Hansbreen is argued to be of thin lower and upper Varanger tillites about 1.5 km thick (minimum) followed by phyllites (?late Vendian) followed by fossiliferous Early Cambrian and Early Ordovician strata mainly carbonates with no evident metamorphism. To the west the post-proto-basement succession is interpreted as a thick Varanger sequence of mobile facies with tilloids,

Caledonian structures

As already remarked, the Hornsund Sorkapp Basement, zone (c) as defined at the beginning of this chapter, exposes in Hornsund, Ordovician, Cambrian and Vendian strata overturned and dipping steeply west. The structure is easterly verging with associated green-schist facies metamorphism and is truncated by an unconformity overlain by flat-lying Triassic strata to the south. The Marietoppen (Mid-Devonian) strata rest unconformably on the eastern margin of the Hornsund-Sorkapp Basement (Murashov 1976) and so constrain its deformation as probably Silurian (Caledonian). At Van Keulenfjorden Dallmann (1988b) has referred to structures in the same basement as Caledonian The lithological layering in the metamorphic basement is folded in a different style and orientation from cover rocks, and is inferred to relate to a mid-Paleozoic Caledonian deformation (Dallmann & Maher 1989a, b). In addition, folds within the basement are truncated by a Caledonian unconformity in the Supanberget area, with similar relationships defined elsewhere. Dallmann & Maher (1989a, b) suggested that the basement rocks were largely deformed by fracturing, slip along foliation and faulting during the West Spitsbergen Orogeny. The massive dolostones that are present in the basement have a strong controlling effect on the deformation of the adjacent cover rocks. Where the dolostones underlie the unconformity, the cover rocks are gently folded into large open flexures, and may be cut by a single brittle thrust fault. Similar geometries and relationships are defined further to the north of Berzeliustinden (Dallmann 1988b). Where the banded phyllite/quartzite sequence underlies the unconformity, the foliation either controls the thrust direction or is rotated into the transport direction, with tight and overturned folds in the overlying strata. The contrast between the degree of basement anisotropy (phyllite/quartzite versus dolostones) and fabric orientation controls the deformation style in the overlying cover strata. Those areas with strongly developed basement anisotropies (phyllite/ quartzite successions) are likely to show more complex deformation in the cover strata (Dallmann & Maher 1989a, b). However, the contrast in metamorphic facies between the Magnethogda gneisses and Cambro-Ordovician strata within a few kilometres and on the same strike implies that the Magnethogda rocks suffered a pre-Caledonian metamorphism.

10.12.4

Jarlsbergian diastrophism

Birkenmajer argued for a diastrophic episode between his Gfishamna (?Vendian) phyllites and the Early Cambrian carbonates and quartzites. There is little evidence of systematic discordance to produce an unconformity with marked overstep. The contrast in composition from phyllites to carbonates raises a further question.

SOUTHWESTERN AND SOUTHERN SPITSBERGEN Nevertheless, this is a possible unconformity with only one clear exposure reported at Slaklidalen in Sorkapp Land. Therefore some warping rather than tectonism may mark the Jarlsbergian Diastrophism.

10.12.5

Proto-basement deformation

The Nordbukta, Isbjornhamna-Eimfjellet, and Magnethogda rocks have already been referred to. They cannot yet be correlated between them stratigraphically or structurally. However the isotopic ages from the Isbjornhamna Group suggest a c. 2.5 Ga age and from the Eimfjellet Group 930 Ma which may reflect a widespread 950Ma event referred to as Grenvillian. Other ages have been claimed such as 594 and 1130, 1135 and 1200Ma. Work is in progress.

10.12.6

Post-proto-basement deformation of Precambrian rocks

This question refers to the age of manifest deformation of mainly Vendian strata, west of the Kongsfjorden-Hansbreen Fault Zone (i.e. the western terranes and in the Section the Coast Horst). The considerations above leave open several possibilities for deformation episodes affecting the pre-Carboniferous and especially the Proterozoic terranes. In the Vimsodden area of the coastal basement basic dykes are displaced by faulting which Birkenmajer (1986) attributed to post-Cretaceous deformation on the presumed basis of their Cretaceous age. The gently northward plunging wide open symmetric syncline in the Varanger strata of northwestern Wedel Jarlsberg Land could be Early Cambrian (Jarlsbergen), Ordovician or Silurian (e.g. Dallmann et al. 1990) or Paleogene. In that western provinces to the north there is no firm evidence of other than mid-Ordovician and Paleogene deformation. In these circumstances Paleogene deformation seems the most likely with thick-skinned structures. Similarly Birkenmajer (1986) attributed crenulation fabric and spaced fracture cleavage in phyllites of the Nottinghambukta Formation to Paleogene deformation, but that could be part of the Czerny et al. (1992) Eimfjellet Group and so be a possible pre-Vendian effect. On the other hand the complex fold and thrust structures in the later Vimsodden and Deilegga rocks have the imprint of Paleogene tectonics. This question has not been faced squarely partly because so much depends on the disputed Precambrian stratal sequence. According to the interpretation here it follows that the Late Varanger succession comprises more competent strata than the Early Varanger strata. This would account for the contrast in the wide open plunging syncline in the north and the exceedingly complex structures in the south where incompetent Deilegga pelites predominate.

10.13

Structure of Sorkapp Land

Sorkapp Land (and Tokrossoya), the southernmost area of Spitsbergen while continuing the structure as seen to the north, at the same time reveals more evidence of late Paleozoic diastrophism which is consistent with a position nearer to Europe with its Hercynian tectonism which Svalbard otherwise largely escaped.

10.13.1

205

outcrop nearly 20km E W . The basin is warped into similarly trending anticlines and synclines, five or six pairs, with wavelength averaging 2 km and amplitudes of about 500 m. This demonstrates a less abrupt eastern margin to the Central Fold Belt. (b) The main fold belt deforming Devonian through Jurassic strata is well exposed on both sides of inner Hornsund. (c) The Hornsund Sorkapp Basement is delineated by N N W SSE-trending faults obscured by similarly trending glaciers. It comprises Late Proterozoic, Cambrian and Ordovician strata, dipping steeply to the west, younging generally to the east, and with thrusts and folds verging eastwards as shown in the profiles N and W of Hornsund (Birkenmajer et al. 1960). These structures are truncated by relatively flat-lying unconformable Triassic strata so defining the main structures as Caledonian. This became the Hornsund High during Carboniferous through Triassic time. To the east, in Samarinbreen and Samarinv~gen, these older rocks are unconformably overlain by middle Devonian Marietoppen Formation strata involved in the Paleogene fold belt. (d) To the west is a terrane of flat-lying Billefjorden and Sassendalen Group strata with a late Carboniferous and Permian hiatus. This would appear to correspond to the Coastal Basement west of the Hansbreen Fault zone in Wedel Jarlsberg Land. It also contains the uncorrelated Sigfredbogen rocks and a slice of the H6ferpynten Formation. (e) In the southernmost tip in Southwest Sorkapp Land and in Tokrossoya is a further NNW-SSE-trending fold belt deforming Permian and Triassic strata and projecting offshore to the N W and subparallel to the coast. (f) Two further Paleogene outcrops occur with the Oyrlandet plain and hill top east of Sorkappfonna and Vasilievbreen. The northern outcrops referred to in (e) and (f) above together with the Proterozoic through Cretaceous-Paleogene extension of the fold belt are separated by wide ice cover from the Sorkapp Land outcrops to the south. This raises questions as to whether there is lateral displacement between north and south. On reflection such a model is rejected, with the consequence that the fold belt, the Hornsund-Sorkapp Basement, and the coastal basement have all been narrowed southward to less than half the width at the latitude of Hornsund. The definitive map of Sorkapp Land sheet C13G of Dallmann et al. (1993) maps five major faults some of which, being straight, must be suspect strike-slip fault zones. The westernmost of these appears to be the southern continuation of the KongsfjordenHansbreen Fault Zone and throws down to the west. The next zone to the east within the Sorkapp Basement appears as a series of thrusts pushing Cambro-Ordovician rocks eastwards over G~shamna phyllites. A fault, or pair of faults, appears to cut the length of the Cambro-Ordovician strata without noticeable effect on the outcrop pattern. Then the main Samarinbreen Fault, hardly constrained because it is within the glacier, divides folded Devonian on Cambro-Ordovician outcrop to the west through its length from a strip of Proterozoic, Devonian and Carboniferous strata to the east, which is separated from Carboniferous strata through Cretaceous strata by a well-constrained thrust fault. The Samarinbreen Fault is shown approximately in line with the fault to the south separating the Oyrlandet Basin to the west from the Proterozoic Basement covered by Triassic strata. This has structural affinity with the Hornsund Basement except that the Proterozoic rocks appear to have more affinity with those (at Mefonntoppane) east of Samarinbreen.

The structural units 10.13.2

The structural zones of Wedel Jarlsberg Land pass across Hornsund south into Sorkapp Land and with some interesting variations. From east to west they are as follows. (a) The southern tip of the Central Basin may be represented in a Paleogene outlier at the extreme east of Sorkapp Land and underlain by Early Cretaceous strata gently undulating and occupying an

Proterozoic structures

Proterozoic outcrops appear almost entirely within the zone of intense (probably) Silurian deformation. The arguments for intraProterozoic tectonism depend more on stratigraphic correlation elsewhere (e.g. whether the H6ferpynten Formation is protobasement). The main consideration here, as in Wedel Jarlsberg

206

CHAPTER 10

L a n d , concerns Birkenmajer's (1960, 1991) Jarlsbergen diastrophism which should be evidenced in s u b - C a m b r i a n structures. Certainly the G~tshamna phyllites are n o t m a t c h e d in the overlying C a m b r o Ordovician succession w h i c h is m a i n l y carbonate. However, most, if n o t all contacts are f a u l t e d - a result of c o m p e t e n c e contrast. Nevertheless, the m a i n thrust faults are m i n o r c o m p a r e d with stratal thicknesses, a n d everywhere the earliest C a m b r i a n strata follow the G ~ s h a m n a phyllite so that a m a j o r u n c o n f o r m i t y is unlikely.

10.13.3

Paleozoic structures

Birkenmajer's (1975) H o r n s u n d i a n diastrophism separates the (Early C a m b r i a n ) S o f i e k a m m e n a n d (Early Ordovician) Sorkapp L a n d Groups. There is evidence of a gentle tilt to the north, so the hiatus widens s o u t h w a r d . But the hiatus is a widespread p h e n o m e n o n a n d not altogether a tectonic one, with a similar hiatus elsewhere in Svalbard, East G r e e n l a n d a n d in Scotland. There is little d o u b t a b o u t the (Silurian) m a i n C a l e d o n i a n tectonism with its resulting eastward-verging overfolding a n d thrusting. This is responsible for the thick o v e r t u r n e d Proterozoic limb, but also for the detailed structure affecting the thinner Early Paleozoic units. The individual structures, evident in the m o u n t a i n s south of middle H o r n s u n d , are well d o c u m e n t e d by Birkenmajer (1978a, b). The resulting structure forms the H o r n s u n d - S o r k a p p Basement on w h i c h the D e v o n i a n ( M a r i e t o p p e n ) F o r m a t i o n rests u n c o n f o r m a b l y . The C a l e d o n i a n diastrophism could have continued into Early D e v o n i a n time. A c o m p l i c a t i o n is that the later Paleogene tectonism is also eastverging a n d p r o b a b l y c o n t i n u e d some of the C a l e d o n i a n thrust surfaces so that at first sight there is continuity of structures f r o m Proterozoic eastwards t h r o u g h Cretaceous. The G~shamna Formation has been thrust upon a sliver of the Cambrian limestones of the Slaklidalen Formation, which were subsequently thrust upon Sorkapp Land Group limestones; the two thrusts formed a fault zone of interconnecting splays. The Sorkapp Land Group to the east is deformed by more thrusts with a similar strike, but has shallower dips. At Rasstupet, the Hornsundtind and Nigerbreen formations are deformed into tight recumbent folds above a shallow westward-dipping thrust fault. To the east of Samarinbreen, the Ggtshamna Formation is deformed by west-vergent folds, which may be related to a backthrust. Along the eastern margin of the Hornsund-Sorkapp High, the contact between the Sorkapp Land Group limestones and the Devonian and younger rocks of the fold belt is unconformable, with a steep eastward and almost vertical orientation (Townsend & Mann CASP). Late Devonian (Svalbardian) tectonism is evident in Spitsbergen to the north. The youngest Devonian deposits in the Hornsund area, based on marine bivalves, are of Emsian to Eifelian age (Birkenmajer 1964). The Adriabukta Formation unconformably overlies the Devonian sediments and is thought to be of Visean age on the basis of palynomorphs (Birkenmajer & Turnau 1962), although in the type area at Adriabukta the upper part of the formation may be divided by an unconformity. But, there is no evidence at Adriabukta for an angular unconformity (Dallmann 1990, 1992). The Adriabukta Formation unconformably overlies Precambrian basement to the east of Samarinbreen and Olsokbreen. In the southern part of PSskefjella, Devonian sediments are attenuated between two adjacent ridges, which may be explained by the formation of an angular unconformity of at least 8~ or by faulting prior to the onset of Carboniferous sedimentation; this is the only evidence in the area of tectonism at the end of Devonian time. Further evidence of Svalbardian tectonics in the Sorkapp Land area is not known. Although not supported by evidence in Sorkapp Land, the postulated strike-slip fault between the central and western provinces would be at latest Late Devonian and probably initiated in Silurian time. Other relatively straight NNW-SSE faults might have the same early history, Sinistral strike-slip displacement may have led to the contrast west of the Hansbreen Fault suggesting subsidence of the West Sorkapp Land Basin.

Early Carboniferous basin development.

The northeastern part of

the West S o r k a p p L a n d Basin is characterized by extensional

structures that trend parallel to the principal N N W - S S E basinb o u n d i n g faults. There is limited evidence for localized early N a m u r i a n deformation, for example small-scale syn-sedimentary faults are identified in the H o r n s u n d n e s e t F o r m a t i o n on K u l m stranda. Evidence for larger-scale d e f o r m a t i o n in the younger, Early Triassic, rocks is not k n o w n here. Associated with the NNW-SSE and NE-SW-trending faults are a number of roll-over anticlines that suggest that some of the extensional faults may have a listric geometry at depth (Mann, CASP). The largest rollover structure identified is related to a NE-SW fault that cuts the whole of the cover sequence on the northwestern part of Sergeijevfjellet, with the closure extending 2 km northwestwards towards Hohenlohefjellet.

Adriabukta tectonic event.

B i r k e n m a j e r (1964, 1975) defined the ' A d r i a b u k t a Phase' on the basis of an angular u n c o n f o r m i t y between the A d r i a b u k t a a n d overlying Hyrnefjellet formations ( S e r p u k h o v i a n - B a s h k i r i a n ) . H o w e v e r , strong folding of the Adriab u k t a F o r m a t i o n , and (3) the thrusting of basement rocks and overlying A d r i a b u k t a F o r m a t i o n strata west onto the A d r i a b u k t a F o r m a t i o n overlying D e v o n i a n rocks require p o s t - A d r i a b u k t a tectonism. Dallmann (1990, 1992) from the interior of Sorkapp Land, at the nunataks of Lebedevfjellet, RokensAta, Smerudknausen and Eggetoppen suggested that the folding and thrusting may be related to the West Spitsbergen Orogen, although there is uncertainty about the presence of an angular unconformity. Devonian strata are tightly folded and are unconformably overlain by shallow-dipping (about 10~ Triassic strata. Dallmann (1992), concluded that the Samarinbreen Syncline is of post-Visean but pre-Triassic age, with the angular unconformity at Adriabukta indicating a mid-Carboniferous age limit (Birkenmajer 1964). At Haitanna the geometrical relationship of the two angular unconformities (Adriabukta and Hornsundneset formations over Caledonian basement) suggests that the Hornsundneset Formation also unconformably overlies the Samarinbreen Syncline. This further constrains the Adriabukta tectonic event to Serpukhovian. The total areal extent of the Adriabukta deformation is unknown. Dallmann (1992) suggested that strain was concentrated along the Samarinbreen Syncline and thrust faults; other deformed zones to the east or west may have developed but are not exposed. Mann (1989, CSE) found evidence of early Carboniferous compression associated with lower green-schist facies metamorphism in Adriabukta.

Carboniferous block faulting.

The N-S trending faults within the Sorkapp b a s e m e n t cut the u n c o n f o r m a b l y overlying Triassic strata, with the relative displacement of the Carboniferous base being greater than that of the Triassic base. Faults within Carboniferous strata m a y be overlain by u n d e f o r m e d Triassic strata (Steel & Worsley 1984; D a l l m a n n 1990, 1992). The age of the faults c a n n o t be constrained closer than p o s t - S e r p u k h o v i a n and pre-Triassic (Steel & Worsley 1984). The sedimentary facies of the Carboniferous strata and their lateral distribution indicate that the fold belt was affected by syn-sedimentary faulting during Carboniferous time. The localised appearance of a thick, proximal delta or alluvial fan facies of the Adriabukta Formation (Haitanna Member) suggests that the assumed boundary fault to the Adriabukta Formation graben (Steel & Worsley 1984) was active during sedimentation. The Hornsundneset Formation (Namurian) is eroded in many areas as a result of faulting in late or post-Namurian time (Dallmann 1990, 1992). The Bladegga conglomerate represents a local facies within the Middle Carboniferous Hyrnefjellet Formation and has been interpreted as an alluvial fan facies related to an active basin margin (Gjelberg & Steel 1981). Deposition of the Bladegga conglomerate was rapid (Birkenmajer 1964), with a transport direction towards the ENE. The local cut-out of the Late Carboniferous-Early Permian Treskelodden Formation at Bautaen suggests the possible continuation of minor fault activity into Permian time (Dallmann 1992). The Late Permian Kapp Starostin Formation shows a thin unit of nearshore facies (about 6 m) in parts of the fold belt (e.g. Austjokeltinden) that may thicken eastwards; the increase in thickness may be related to activity along the Inner Hornsund Fault Zone during Triassic time (Mork et al. 1982; Dallmann 1992).

SOUTHWESTERN AND SOUTHERN SPITSBERGEN

10.13.4

Mesozoic structures

The H o r n s u n d - S o r k a p p High was covered by a relatively condensed sequence of early Triassic sediments by Dienerian (Early Nammalian) time compared with other areas of Spitsbergen (Worsley & M o r k 1978), e.g. the westward thickening of Triassic sediments offshore (Eiken & Austegard 1987). Evidence for minor tectonic instability during early Triassic time is seen along the eastern margin of the West Sorkapp Land Basin at Kovalevskifjellet and Savitsjtoppen, where the base Triassic unconformity is displaced by several extensional faults, and is overlain by AnisianLadinian (Botneheia Formation) sediments. The tectonic instability occurred before the late Triassic (post-Ladinian) phase of extensional faulting that affects the Sassendalen Group in Van Keulenfjorden (Mann CASP).

10.13.5

Paleogene structures

The West Spitsbergen Orogeny resulted in conspicuous tectogenesis not paralleled since Caledonian events in Svalbard. Probably with an Eocene climax it is reasonable to attribute any major deformation of Carboniferous through Paleocene strata to this event.

Post-Jurassic tectonics in the west. A series of relatively open NNE-SSW-trending folds deform both the Triassic sediments at Lidelva and the Triassic and Jurassic sequence at Roysneset, where a well-developed cleavage is associated with the folds. Offshore seismic data provide some evidence for the compressional reactivation of an extensional fault (e.g. Eiken & Austegard 1987) along which Carboniferous and Mesozoic sediments have been uplifted (Mann, CASP). The fold axes at Roysneset show an anticlockwise transection by cleavage surfaces suggesting that a component of dextral strike-slip may have been involved in the development of these folds. This may reflect localised deformation rather than regional tectonics. F r o m paleostress tensors the Wurmbrandegga Fault was considered to have a dextral offset by Lepvrier, Le Parmentier & Seland (1988) and to be related (reactivatedly) to the West Spitsbergen Orogeny. The Central Fold Belt in Sorkapp Land. The fold belt in Sorkapp Land forms a prominent NNW-SSE-trending lineament, though it is considerably less pronounced when compared with areas further north. The Fold Belt comprises a zone, 5-10 km wide, of folded and thrust Late Paleozoic to Mesozoic strata, with fold trends broadly parallel to the N N W - S S E trend of the lineament. The principal source of information regarding the structure of the fold belt in this area is that of Challinor who mapped an area between Inner Hornsund and Storfjorden at a scale of 1: 25 000. A 1: 100 000 scale map of Hornsund, Sorkapp Land and part of Wedel Jarlsberg Land was compiled by Challinor (CSE) using both published and unpublished data (R6zycki 1959; Birkenmajer 1959, 1960a,b, 1964; Birkenmajer & Narebski 1963; Major & Winsnes 1955; Siedlecki 1960; Nagy 1966) and was partly updated by the structural work of Mann (CASP). The absence of significant compressional structures in this area indicates that the fold belt in Sorkapp Land, in contrast to areas further north, is structurally relatively simple. Challinor constructed a series of cross-sections through Wedel Jarlsberg Land and Sorkapp Land (Fig. 20.8) that illustrate the principal features. He interpreted these cross-sections assuming that the development of folded thrust fault trajectories was the result of competence differences between layers of previously folded strata. Using later techniques, it is found that thrusts were folded subsequent to initial thrust displacement, and that thrust trajectories can be modelled according to ramp and fiat geometries. The original cross-sections of Challinor cannot be balanced, but do contain the elements for producing a balanced cross-section, i.e. ramps, fiats and equal length cut-offs in the hangingwalls and footwalls to thrust faults (Townsend & Mann, CASP). The structural inversion produced east-verging folds and minor thrusts, but without significant stratigraphic repetition (Mann & Townsend 1989).

207

Shortening estimates, based on restored cross-sections for this area compiled from Challinor (1968, CASP), indicate between 4 and 6 km of ENE-WSW shortening. Surface structures that define the fold belt have been mapped for 30 km to the south of Hornsund. In the Sorkapp Land segment, there is a distinct lack of compressional structures along strike (Major & Winsnes 1955; Flood et al. 1971; Orvin 1940; Livshits 1973). Welland (CSE) similarly failed to recognise compressional structures along the projected fold belt line. However, at Oyrlandet in southwest Sorkapp Land, Permian strata exhibit steep to vertical bedding. Assuming that the steep dips at Oyrlandet are the result of Cenozoic compression, and that the fold belt may not be offset by E W or NE-SW dextral strike-slip faults.The explanation may be that some shortening associated with the orogeny transferred from an east to a west zone of folding. Birkenmajer's (1964) section illustrates a sequence ofkilometre-scaletight folds, which are in part overturned. The Kvalfangarbreen Thrust, a westdipping structure beneath Hyrnefjellet, cuts through this folded sequence, with evidence in the eastern part of later extensional reactivation. Dallmann (1988a, b, 1990) suggested a model to explain the Inner Hornsund structure as a result of continuous compressional deformation. The Kvalfangarbreen Thrust was originally a westward-directed backthrust developed above an implied eastward-directed basement-involved thrust at depth, i.e. a wedge type geometry (cf. Dallmann 1988a). The backthrust ramps upward from Carboniferous to Cretaceous strata and is inferred to accommodate a minimum shortening of about 3 km. The backthrust, to the south of Hornsund, is structurally similar to the Berzeliustinden Thrust in Wedel Jarlsberg Land (Dallmann 1988a, b). The Hyrnefjellet section provides a m i n i m u m shortening estimate of about 7 km, or about 10 km if shortening amounts to the west or east of the section are included. Near Sorkapp, 40 k m further south, there is no significant shortening at Keilhaufjellet, though it is unlikely that the fold belt entirely disappears, but rather the shortening is transferred to the west. The root zone of the fold belt appears to follow the Inner Hornsund Fault Zone, with the western area of the Hornsund-Sorkapp High behaving as a stable block. Dallmann (1990) suggested that there is tectonic repetition of Mesozoic strata in the suggested thrust structure at Lidfjellet, forming an east-vergent thrust system that would necessitate another root zone offshore to the west. Down-faulted Late Paleozoic and Triassic strata on Oyrlandet and Sorkappoya show many folds with a similar trend to those of the central fold belt, though again, there is no clear evidence for the age of this deformation.

The fold-and-thrust belt in central Sorkapp Land. The southern part of the Tertiary fold-and-thrust belt structurally overprints the eastern part of the Samarinbreen Syncline and adjacent areas to the east as seen within a distance of 10kin to the north and south of Hornsund where detailed mapping has been concentrated (Birkenmajer 1990; Dallmann 1990, 1992). The following structures are critical to the development of a kinematic model. (i) The east-vergent Braemfjellet Thrust emplaces Vendian basement and overturned Devonian rocks on overturned Triassic strata. (ii) The east-vergent Kvalfangarbreen Thrust emplaces highly deformed Cretaceous and Jurassic rocks on overturned Triassic and Permian strata; the thrust is refolded. (iii) The Hyrnefjellet Antiform and adjacent synform deform both Late Paleozoic and Early Triassic rocks. (iv) The west-vergent Mariekammen Thrust emplaces basement with overlying Lower Carboniferous strata on Lower Carboniferous overlying Devonian strata; the thrust is sub-vertical (Birkenmajer 1964). (v) West-vergent structures and hanging-wall cutoffs in Late Paleozoic strata. (vi) The eastward overturned Strykjernet-Isryggen Fold deforms Cretaceous strata. (vii) The P/~skefjella Thrust emplaces basement on highly deformed Lower Carboniferous strata; this may relate to the Adriabukta tectonic event. The model, favoured by Dallmann (1992), explains the development of the principal structures by continuous compression, incorporating

208

CHAPTER 10

back-thrusting and wedge insertion. Shortening estimates are as follows: (1) the Braemfjellet Thrust (about 500m), (2) recumbent fold (4.5km), and (3) Kvalfangarbreen Thrust (about 3kin) (Birkenmajer 1964, 1977; Dallmann 1992).The minimum amount of total shortening, assuming a back-thrusting model, is 8 km across the structure to the north of Hornsund. The total amount of shortening across the fold belt at Hornsund is about 10-12km or possibly greater assuming further displacements are accommodated further east (Dallmann 1992). The area to the south of Hornsund may represent a lower structural level, where the basal detachment of the tectonic wedge is exposed. Tertiary deformation diminishes to the south through the orogen. In the area around Haitanna, there is probably only a regional flexure which decreases southwards to Keilhaufjellet where only a simple monocline dipping towards the Central Spitsbergen Basin is identified (Dallmann 1990, 1992). At Keilhaufjellet in the south, shortening is estimated at 200-300 m and was caused by minor folding of the Central Spitsbergen Basin strata. Measurements at Haitanna suggest that approximately 700 m of shortening was accommodated by regional flexuring of the Triassic strata; similar estimates indicate a minimum of 1.8km across the southern part of P~skefjella.

area, and are considered to relate to the development of the western Svalbard continental margin during Oligocene time (Dallmann 1990). Some faults may have developed during an Early to MidPaleocene extensional/transtensional phase (Steel & Worsley 1984). Deformed Triassic strata in the H6ferpynten area suggest that the faults formed prior to the main Late Paleocene-Eocene compressional phase (Dallmann 1992). Paleogene reactivation of earlier faults is evident in the H6ferpynten area where the displacement of Early Carboniferous strata is greater than that of Triassic strata. Many of these faults are cross-cut by compressional structures, as evident in the Oyrlandet Graben, Lidfjellet-Oyrlandsodden Fold Zone and the Fold Belt (Dallmann 1992). A major NNW-SSE-trending fault through Inner Hornsund has a maximum downthrow to the northeast of about 1.5 km at Condevintoppen/ Firlingane (Dallmann 1992). At Tsjernajafjellet, south of Hornsund, the displacement is reduced to about 100 m; the lateral extent is not known due to extensive ice cover (Dallmann 1990, 1992).

The Lidfjellet-Oyrlandsodden fold zone. The Paleocene strata on Oyrlandet are down-faulted, but in the limited exposures these strata appear otherwise undeformed. Seismic studies of the Central Spitsbergen Basin indicate that deformation occurred within preTertiary strata, while Tertiary and some Cretaceous strata were uplifted and remained apparently undeformed (Faleide, Myhre & Eldholm 1988). The Lidfjeilet Oyrlandsodden Fault Zone extends south through Sorkappoya from the southernmost point of the main fold-and-thrust belt; however, the lateral extent of this fold zone is not known. This may be an en echelon arrangement of the two fold belt zones (Dallmann 1992). Within the Lidfjellet-Oyrlandsodden Fault Zone, at Lidfjellet, the minimum offset of the Triassic base suggests a minimum thrust displacement of 1.8 km.

Evidence of strike-slip. There is local evidence for strike-slip motion within the fold-and-thrust belt of Sorkapp Land. From an analysis of fold axis rotations Dallmann (1992) proposed that the two motions were decoupled (e.g. Maher & Craddock 1988) with a phase of strike-slip motion along pre-existent ENE-WSW-dipping fault planes. In the area where the Hornsund Sorkapp mobile zone and of Lidfjellet-Oyrlandsodden Fold Zone a further indication of dextral transpressional motion may be the oblique arrangement of several normal faults. It is unclear whether this transtension is of Tertiary or Late Paleozoic age, since the Tertiary movements may simply have reactivated pre-existent structures. Near the Eastern Hornsund Fault at Tsjernajafjellet, large-scale drag folds and faults which show dextral strike-slip and a downthrow to the east occur in strata of Triassic age; the oblique slip is inferred to be of Tertiary age (Dallmann 1992).

Tertiary extensional faulting. Normal faults trending N N W - S S E cross-cut the central and western parts of the Hornsund-Sorkapp

A synthesis of the West Spitsbergen Orogeny is attempted in Chapter 20.

Chapter 11 Southern Svalbard: Bjornoya and submarine geology W. B R I A N 11.1 11.2 11.3 11.3.1 11.3.2 11.4 11.4.1

HARLAND

with contributions with ISOBEL

Early work, 210 Geological frame of Bjornoya, 212 Triassic strata of Bjornoya, 212

The Skuld Formation, 213 The Urd Formation, 213 Late Paleozoic strata of Bjornoya (W.B.H. & I.G.), 213

Miseryfjellet Formation (Tempelfjorde Group), 213 Hambergfjellet Formation (group undecided), 214 Kapp Dun~r Formation (Gipsdalen Group), 214 Kapp Hanna Formation (Gipsdalen Group), 215 11.4.5 Kapp Kfire Formation (Gipsdalen Group), 215 11.4.6 Landnordingsvika Formation (Gipsdalen Group), 216 11.4.7 Nordkapp Formation (Billefjorden Group), 216 11.4.8 Roedvika Formation (Billefjorden Group), 217 Pre-Devonian strata of Bjornoya, 218 11.5 11.4.2 11.4.3 11.4.4

The area south of Spitsbergen (about 76~ to latitude 74~ and between longitudes 10~ and 35~ by which Svalbard was first defined, contains the small island of Bjornoya (Bear Island, B/iren Insel) and the rest is sea (Fig. 11.1). The 500 m isobath conveniently separates the edge of the Barents shelf from the Norwegian Sea Basin which runs south from Spitsbergen between 14 ~ and 16~ To the east, the large shallow area, Spitsbergenbanken, less than 100m deep, supports Bjornoya at its southwestern end, extends northeast to Hopen and joins Edgeoya. It is separated from Spitsbergen to the north by the Storfjordyrenna and to the east by Hopendjupet. These submarine valleys appear to drain westwards into the ocean deep with deltaic fronts convex westwards.

11.5.1 11.5.2 11.6 11.6.1 11.6.2 11.6.3 11.6.4 11.7 11.8 11.8.1 11.8.2 11.8.3 11.8.4 11.8.5

GEDDES

& PAUL.

A. D O U B L E D A Y

Ymerdalen Group, 218 Bjornoya Group, 219 Structural sequence of Bjnrnoya, 219

The basement, 219 The cover sequence, 220 The platform sequence, 222 Post-platform structure, 222 Submarine outcrops, 222 Submarine structure (W.B.H. & PA.D.), 222

Continental margin: Knipovich Ridge to the Hornsund Fault Zone, 222 Vestbakken Volcanic Province, 223 Stappen High, 224 Sorkapp Basin, 224 Crustal structure and a possible Iapetus suture, 224

This chapter focuses first on Bjornoya which though small is a key outcrop in the Barents Sea and distinct in m a n y respects from Spitsbergen being about 250 km distant. The chapter then surveys a little of what is known of the surrounding sub-sea area. Bjornoya (20 km N-S and 15 km E W), as the southern outpost of Svalbard, has long been a key to Svalbard geology since it is generally free all year from tight sea ice. But though its location is convenient, its cliffs generally bar access. Indeed there are very few places where landing by other than inflatable dinghy are feasible. After the island had been claimed by a Norwegian syndicate in 1915 mining of Tournaisian coal began in 1916 and exported over 116 000 tonnes before the work ceased for economic reasons in 1925. The coal was loaded directly off an exposed cliff into the boat's hold.

Fig. 11.1. Bathymetric map of the western Barents Sea around southern Svalbard, with principal bathymetric features named, based on 1 : 2 M bathymetry chart of the Western Barents Sea, Norsk Polarinstitutt, Oslo 1989, compiled by Kristoffersen, Sand, Beskow & Ohta.

210

CHAPTER 11

NATHORST1910 partly from i ANDERSSON 1900 14 i Myophoria 20m * i Sandstein

13

~

i

HOLTEDAHL 19201HORN & ORVIN 1928 i i -I

Schiefer

C

11 i Korallensandst. i 10 i Fusulinenkalk

8

i

io

i i

~ Sandstein ohne Fossilien

Ambigua kalk

i !

i i

i :i i i

Cora Limestone

(1)

HARLAND et al. 1993" S M I T H & ARMSTRONG 1996 1SKS 1996

Skuld Fm

Miseryfjellet

i Alfredfjellet Fm

~: Hambergfjellet

Fm Fm

i

No group designated SKS

i

Yellow Sandstone Ambigua Limestone

Kapp Duner Fm

Kapp Dun6r Fm

I Kapp Hanna Fm

Kapp Hanna Fm

i

Kobbebukta Fm

................................

Red Conglomerate Nordkapp

Fm

i

Ursa

~

Sandstone

i Tetradium Lst 1 i (Black River) 240 i Younger dolomite 1" (Canadian) 400m ~ g

& 1976

LaksvatnetFm

i

O < O -"

iDarkred& greenish grey (2) Slate Light grey quartzite Sandstone (3) grey & red dolomite Tetradium limestone (4)

TEMPELFJORDEN GP

Spirifer Limestone

WORSLEY EDWARDS

Verdande Bed Urd Fm

L~arK tiSSile snaies

Fusuline Limestone

S. :,

Sandstein

1

i i

i

iS" i F ~o

Ursa

2

g

A i

6

3

SkuldFm

i

L Diskordanz

4

i

a' { ~" i z A

7

5

i

i

i

Diskordanz

_

MyophoriaSandstone

.......................................................... Dunke dunsch eft ge cn i . . . . . . g

12 i Spiriferenkalk

9

i i

CUTBILL & K R A S I L ' S H C H I K O V CHALL NOR[ & i 1965 i[ LIVSHITS 1974 ......................... i-

m

r--r- Nordkapp Fm m

Soed-~; vika Fm

I I i I kandnordingsvika Fm

m z

I I

(Uzankian) 400m

3~

Landnerdingsvika Fm Nordkapp Fm

i

i

Slate quartzite "l175m Older dolomite l-

Bogevika Mbr

i

i Ymerdalen Fm t

Kobbebukta Mbr. SKS

Efuglvika Mbr

iIi

i Sorhamna Fm Russehamna Fm

Antarcticfjellet 1 i Fm i YMERDALEN Perleporten 1" ! GROUP Fm i Sorhamna Fm i BJORNOYA* ', GROUP Russehamna Fm

B

Fig. 11.2. Summary of stratigraphic schemes for Bjornoya.

Later the settlement was abandoned and the meteorological and radio station moved to the north coast where there is a better direct landing facility to which supplies are ferried by small boat and raft from vessels standing out to sea. There is no airstrip but long distance helicopters supplement the occasional visits by ship. Sulphide mineralization affected the Ymerdalen Group and possibly older rocks. Galena was mined on a trial scale. A Caledonian age seems likely. For a source of metallic-bearing fluids it is noted later in this chapter that Bjornoya may have long been part of eastern North Greenland. The other mineralization in Svalbard (especially southwest Spitsbergen) which, while probably not Caledonian, nevertheless was associated with basement terrane also closely related to the North Greenland shield (Horn & Orvin 1928; Flood 1969).

11.1

Early work

Bjornoya was noted for its coal from 1609. The first recorded geological visit was by the Norwegian Keilhau in 1827 (1831). The next was probably by Nordenski61d in 1864 (Duner & Nordensk i n d 1867) and in 1868. Material collected on those expeditions continued to provide for paleobotanical studies especially by Heer (1872). Further Swedish expeditions in 1898 and 1899 resulted in several key publications (Lindstr6m 1899 and Andersson 1900) on the older rocks, B6hm on the Triassic rocks (1899, 1903), and Wiman on Late Paleozoic brachiopods (1914). At the same time

reports on the coal potential were made (e.g. M611man 1900). These and other results were synthesised in Nathorst's (1910) monograph. The mining facilitated further Norwegian work with Holtedahl's investigations in 1918 (1920b) of the older rocks. This led to his making a geological map of the whole island (e.g. 1926). A topographical survey to a scale of 1:10000 followed in 1922 and 1923 and, no doubt prompted by the diminishing coal prospects, Horn and Orvin surveyed the whole island in 1924 and 1925 resulting in a report (1928) with a geological map to a scale of 1 : 25 000. This remained the definitive geological monograph on the island until sheet D20G, 1:50000 (Dallmann & Krasil'shchikov 1996). Indeed most subsequent work had used the map units and their boundaries directly from the map of Horn & Orvin with one exception. Krasil'shchikov & Livshits (1974) reported on systematic work on most parts of the island by their Leningrad team. Their map still largely followed that of Horn & Orvin, with a few changes in the boundaries and these have been incorporated in the 1996 map (see Fig. 11.3). In addition, to the mainly structural study of Krasil'shchikov & Livshits a number of investigations have been published specialising especially in further biostratigraphic and sedimentological interpretations. These will be mentioned in the following pages. During these studies contemporary nomenclature has been introduced step by step. The remarkable fact is that the map units resulting from Swedish work and summarized by Nathorst (1910) and refined somewhat by Horn & Orvin (1928) have stood the test of time. Changes in nomenclature are depicted in Fig. 11.2.

Fig. 11.3. Geological map with sections of Bjornoya derived from the map of Horn & Orvin (1928) and using contemporary names for their rock units. Principal lakes identified (numbers in circles): (1) Djunvatnet; (2) Hobethvatnet; (3) Holmvatnet; (4) Kalven; (5) Krokvatnet; (6) Lomvatnet; (7) Lygna; (8) Lysingen; (9) Oyangen; (10) Snelvatnet; (11) Stevatnet; (12) Vomma.

S O U T H E R N SVALBARD: BJORNOYA A N D S U B M A R I N E G E O L O G Y

211

212

11.2

CHAPTER 11

Geological frame of Bjornoya

The geological m a p (Fig. 11.3) based on that of H o r n & Orvin (1928) shows the outcrops of the principal f o r m a t i o n s modified where the m a p of K r a s i l ' s h c h i k o v & Livshits (1974) differs. Figure 11.4 summarizes the seismic and porosity characteristics o f the principal B j e r n o y a formations. In the Sections 11.3 to 11.4 the Triassic, Late Paleozoic and pre-Silurian f o r m a t i o n s respectively are outlined f r o m the top down. The structure o f B j o r n o y a is then treated in Section 11.5 where a different grouping related to the tectonic history is employed n a m e l y basement, cover and p l a t f o r m sequences. A s u m m a r y o f the stratigraphic sequence follows, with early n a m e s in parentheses:

Kapp Toseana Gp Skuld Fro, 140+m (map unit 14) Shales and siltstones.

?Ladinian and Carnian

AGE ~

Tempelfjorden Group Miseryfjellet Fm (Spirifer Limestone), 115-120m (map unit 12). Sandy and partly silicified highly fossiliferous (biosparite) limestone with sandstone at base. KunguriamUfimian UNCONFORMITY [Group not assigned] Hambergfjellet Fm (Cora Limestone), 0.50 m (map unit 11). Limited to SW Bjornoya Limestones and sandstones. Artinskian-Sakmarian UNCONFORMITY

Billefjorden Gp Nordkapp Fm (upper Ursa Sandstone or Cuhn), l l0m in S to 230m subsurface in N (unit 6). Cross-bedded, grey sandstones with occasional conglomerates, shales and thin coals. Visean Tournaisian Roedvika Fm (lower Ursa Sandstone), 100 m in SW to 36 m at Tunheim in NE (unit 5). Sandstones, shales and coals. Famennian Early Tournaisian Tunheim Mbr, 80m grey sandstones, shales, local conglomerates and coal seams (mined at Tunheim). Tournaisian Kapp Levin Mbr, 80 m mainly sandstone. Veselstranda Mbr, 200 m, grey and purple sandstones and shales. Famennian ANGULAR UNCONFORMITY Ymerdalen Gp, 560 57 m Antarcticfjellet Fm (*Tetradium Limestone), 93-240m (unit 4), grey linestones (rich on fossils). Latest Llanvirn-Early Caradoc Perleporten Fm (Younger Dolomite Series), 250 400+ m (unit 3), pale grey dolostones (poor in fossils). ?Canadian UNCONFORMITY (not younger than latest Llanvirn to Early Caradoc)

Bjernoya Gp Sorhamna Fm (Slate Quartzite Series), 175+ m (map unit 2), green and red shales with quartzitic sandstones. Russehamna Fm (Older Dolomite Series), 400+ m (map unit 1). Variegated massive dolostones, partly oolitic, arenaceous in upper part.

10% 20% I

lOO

-

-

MINIMAL NET SUBSIDENCE RATE (mm y )

I

0.01 Miseryfjellet

0.01

Kapp Duner

0.02

-

500

Kapp Hanna -

O i.u u_

Kapp K~re

O

_Landnordingsvika

< O

_

1000

>~ 13

i

\

I

q

0.03

l-/_

\

]

1-

_Nordkapp

0.02

0.03

0.006

0.015

Roedvika

_

u_ _

1500 o

Antarcticfjellet

0~

0.017 O

Gipsdalen Gp Kapp Dun~r Fm (Fusuline Limestone), 75+ m (map unit 10). In western Bjornoya Mainly dolostones and dark limestones with fusulines. Asselian Gzelian Kapp Hanna Fm (Yellow-Sandstone), 150m (map unit 9) in western Bjornoya extending north to south. Is mainly of yellowish calcareous sandstones with shales, limestones, dolostones and conglomerates at base. Kasimovian Moscovian DISCONFORMITY Kapp Kfire Fm (Ambigua Limestone), (map unit 8). Mainly of grey limestone with the brachiopod Composita ambigua. Moscovian Bashkirian. Kobbebukta Mbr (SKS 1996), 8-45m. Carbonate and chert debris flows, conglomerate and marine limestones. Efuglvika Mbr, 80 m, cherty biomicrites. Bogevika Mmbr, 90m limestones, dolostones, sandstones and shales. Landnordingsvika Fm (Red Conglomerate), 145 m in SW and 120+ m in N (unit 7). Red sandstones and conglomerates. Bashkirian

POROSITY

_o

Sassendalen Gp Urd Fm, 65m (map unit 13) Verdande Bed (at top) a conglomeratic remani~ bed of phosphatic concretions. The body of the formation is of dark fissile shale with clay ironstone concretions and thin limestone and interbedded silstones with sandstones at base. Early Triassic (Scythian) to Early Ladinian

FORMATION

SEISMIC VELOCITY (kms') 4 5

~ o

Perleporten _

200C Sorhamna

0.037

R u s s e h a m n a

0.05

250( -

-

i

Fig. I 1.4. Summary plot of seismic velocity, porosity and estimated minimal subsidence rate adapted (except for right-hand column) from Gronlie, Elverhoi & Kristoffersen (1980) who also remarked, with growth of quartz and clay minerals, that silica cementation increases upwards and there is also some calcite dolomite mineralization. They discussed the problem of why at greater depth Roedvika sandstones show much greater porosity. Differential accumulation of core strata may have given lower than expected overburden in Bjornoya. The 1500 m of post-Silurian strata were formed during no more than 150 million years, a net subsidence rate of 0.01 m m a -1. The right-hand column attempts to compare subsidence rates for each lbrmation making crude assumptions. Even so the overall subsidence rate is consistent with a secular contraction of the mantle through cooling (cf. Harland 1969). (Reproduced with kind permission of Elsevier Science, Amsterdam.)

11.3

Triassic strata of Bjornoya

Triassic rocks are the youngest pre-Pleistocene strata in Bjornoya. They occupy the top of the highest m o u n t a i n , Miseryfjellet, on w h i c h three peaks, Skuld, V e r d a n d e a n d U r d have been used for the principal n a m e d Triassic units. The u p p e r f o r m a t i o n (Skuld) belongs to the K a p p T o s c a n a G r o u p of Spitsbergen and the lower f o r m a t i o n (Urd) to the Sassendalen G r o u p on the basis of similar lithologies (as well as age). The V e r d a n d e Bed is a conglomerate at the top of the U r d F o r m a t i o n . The Triassic fauna was first investigated by B o h m (1899, 1903), palynology by M o r k , Vigran &

SOUTHERN SVALBARD: BJORNOYA AND SUBMARINE GEOLOGY

213

Hochuli (1990) and geochemical studies were reported by Bjoroy, Mork, Vigran (1980, 1983, 1987).

A summary of the sequence is given in Section 11.2. Much of the following detail, especially the sedimentology, is from Worsley & Edwards (1976) and Gjelberg & Steel (1981).

11.3.1

11.4.1

The Skuld Formation (>140m)

The Formation was named by Krasil'shchikov & Livshits (1974) and further defined (but not mapped) on Miseryfjellet by Mork, Knarud & Worsley (1982). It is the upper part of the Triassic sequence (above the Verdande Bed) and the lateral equivalent of the lower part of the Kapp Toscana Group, i.e. the Tschermakfjellet and lower De Geerdalen Formation elsewhere on Svalbard. Dark grey shales with red-weathering siderite nodules (cf. the Tschermakfjellet Formation) rest on the phosphatic conglomerates of Verdande Bed at the top of the Sassendalen Group. The top has been removed by recent erosion. There is an upward-coarsening sequence similar to that seen elsewhere with the c o m m o n thin siltstones, becoming thicker, and fine-grained sandstones appearing at the top of the unit (at the highest level preserved) where there are 20 m of plane-laminated sandy siltstones. Marine fossils are present t h r o u g h o u t - bivalves, brachiopods and ammonites, especially in the upper half, while plant fragments appear at the highest levels present. These indicate a Late Ladinian (sutherlandi zone) to Early Carnian age (Pchelina 1972; Tozer 1967; Tozer & Parker 1968). A labyrinthordont was found high up in this succession (Lowy 1949).

11.3.2

The Urd Formation (65 m)

The formation was named by Krasil'shchikov & Livshits (1974) and defined more closely by Mork, Knarud & Worsley (1982) with a section on the southern slope of Urd, the highest peak of Miseryfjellet. It is approximately equivalent to all other units of the Sassendalen Group elsewhere. The Verdande Bed, 20 cm, at the top, is the condensed lateral equivalent of the Botneheia Formation. It is a conglomerate composed of eroded grey phosphate (carbonate-apatite) nodules 2.5 6cm in diameter. It is glauconitic. Phosphate nodules are distinctive constituents of the Middle Triassic throughout Svalbard (in the Botneheia Formation) which are here condensed into the remani~ bed which forms a good marker horizon on Bjornoya. Below are 62 m of alternating thinly bedded grey siltstones and silty shales. Carbonate-rich lenses and minor yellow-weathering dolomitic limestones appear in the upper part. The basal 3 m of the formation consists of fine sandstones which rest with sharp, locally unconformable, contact on Permian limestones. A variety of marine fossils including ammonoids suggests an ?Induan (not proven) Smithian age for the strata below the Verdande Bed (Pchelina 1972). In addition, sponge spicules, echinoderm fragments, fish vertebrae, bivalves and gastropods have been reported, some of which may be derived from the Permian beds below. The Verdande Bed contains various fossil remains of dubious identity and in view of the faunas above and below seems to represent Mid-Triassic (Anisian-Early Ladinian) time. There may be a time gap below the Verdande Bed (as might be expected from its nature), with the top of the Smithian and Spathian substages unrepresented. Arctoceras blomstrandi of Early Smithian age occurs just below the Verdande Bed.

11.4

Late Paleozoic rocks of Byjornoya (I.G. a n d W . B . H . )

Late Paleozoic rocks in Bjornoya occur throughout most of the island (Fig. 11.3). As elsewhere in Svalbard, with one possible exception they are contained within the three groups: Tempelfjorden, Gipsdalen and Billefjorden. The groups (defined in Spitsbergen) we represented in Bjornoya by eight formations as follows.

Miseryfjellet Formation (Tempelfjorden Group)

This formation, 115 m, consists almost entirely of limestone except for sandstones at the base. The latter infills karst structures in underlying limestones, and hence represents a transgression. The limestones represent high energy shallow marine environments, with shoreface, littoral and barrier deposits. The formation is of Kugurian, Ufimian and possibly Wordian age.

Definition. The Miseryfjellet Fm of the Tempelfjorden Group is the youngest late Paleozoic unit of Bjornoya. It was the 'Spirifer Limestone' of Nathorst (1910) and of Horn & Orvin (1928) owing to the abundant brachiopod fauna. Soviet geologists named it the Laksvatnet Formation (Pchelina 1972; Krasil'shchikov & Livshits 1974). Siedlecka (1975) described the petrography. Worsely & Edwards (1976) renamed the unit the Miseryfjellet Fro, as the only complete sections through the formation are on the slopes of Miseryfjellet, where there are approximately 115m of limestones and sandstones. However, the type sections occur at Brettingsdalen and Herwigshamna (Hellem in the IKU 1987 Excursion Guide to Bjornoya). The upper boundary is seen only on Miseryfjellet, where the formation disconformably underlies Triassic shales. The lower boundary is an unconformity, with a local basal conglomerate and calcareous sandstones overlying various older units (successively older units of the Early Carboniferous Nordkapp Fm in the north; Permian and pre-Devonian sequence in the south). Lithologies. Limestones, with a rich brachiopod fauna and partially silicified, make up 90% of the succession in which biosparites and biorudites, generally arenaceous, predominate. They are irregularly bedded, dark grey, highly fossiliferous and commonly partly silicified. Arenites make up about 10% of the sequence. In general, the sandstones are fossiliferous, with calcite, quartz or (rarely) dolomite cement. Porosity and permeability are both low. Some beds of cherty siltstone form the base of the formation, where they are usually 1-3 m thick and locally pebbly to conglomeratic. Medium to fine-grained quartzitic and calcareous sandstones occur in a 12 m bed, 20 m above the base on Miseryfjellet. This bed coarsens upwards and has tabular and lower-angle cross-bedding, directed southeastwards, at the top. On the north coast at the top of the formation, wedgelike sand bodies also appear. At the base are sandstones. Locally they infill 8-10m deep karstic features in the underlying Kapp Dun6r and Kapp K~re fms. In the basal sandstones, marine burrows extend down into the underlying Carboniferous rocks in some localities and Siedlecka (1975) noted moderate to good sorting with a distinctly bimodal size distribution. Conglomerates occur at the base of the formation in places, and also capping the 12 m sandstone on Miseryfjellet described above. The basal conglomerate clasts are derived from the underlying units. Quartz pebbles up to 11 cm in diameter show no preferred orientation. Palaeontology and age. Brachiopods, bivalves, crinoids, bryozoans and some corals occur, with Skolithos burrows in the sandstones (Holtedahl, 1925). Gobbett (1963) described seventeen brachiopod species from the formation, all of which also occur in the Kapp Starostin Fm. There is little doubt that the two formations correlate. Nakrem (1988) began a study of the conspicuous bryozoan element in the Tempelfjorden Group and later monographed the work in (1994). Ustritskiy (1971) and Ustritskiy & Cernjak (1973) assigned the youngest beds to the Ufimian stage, but continue the North American-Arctic sequence into Wordian time. Examination of CSE brachiopod collections (J.B. Waterhouse pets. comm.) suggested a Wordian or Late Kungurian age, though there are no definite Wordian indices. Nakrem (1991) on the basis of conodonts suggested a Kungurian-Ufimian age. The Miseryfjellet Fm is therefore of Kungurian, Ufimian and possibly Wordian age. The basal unconformity is comparable with that at the base of the Kapp Starostin Fm in Spitsbergen, and the fossiliferous biosparites are comparable with those of its Voringen Mbr. 11.4.2

Hambergfjellet Formation (group undecided)

This unit, 100 m is also dominated by limestone except for sandstones at the base. It is characterized by evidence of periods of

214

CHAPTER 11

e m e r g e n c e a n d erosion; its base is an u n c o n f o r m i t y a n d karstification structures (infilled by sandstone), calcretes a n d rootlet horizons are present at several levels t h r o u g h o u t . It is t h e r e f o r e a s h a l l o w - m a r i n e unit but one t h a t was subject to rapid changes in relative sea-levels. It is o f A r t i n s k i a n to ? S a k m a r i a n age based on fusulinid a n d b r a c h i o p o d assemblages.

Definition. The Hambergfjellet Formation is mainly a carbonate sequence between two unconformities. It is confined to the southwest of the island. The formation was named the Cora Limestone by early workers because of the occurrence of the brachiopod Linoproductus dorotheevi, identified then as Productus cora (Anderson 1900). This name was used by Horn & Orvin (1928) and Cutbill & Challinor (1965). It was renamed the Alfredfjellet Formation by Krasil'shchikov & Livshits (1974) and then the Hambergfjellet Formation by Worsley & Edwards (1976). There is no single type section defined, but exposures from two localities, Alfredfjellet and Hambergfjellet, cover the whole section from base to top. The upper boundary is marked by the low angular unconformity at the base of the Miseryfjellet Formation which oversteps it to the south and east. The top is partly silicified and has a micro-karstic surface. The lower boundary is at a clear unconformity representing a period of extensive uplift and erosion. The formation overlies Precambrian, Devonian and Carboniferous strata and at Alfredfjellet it overlies the earlier Permian Kapp Dun& Formation. The Hambergfjellet Formation is currently not included in either the Tempelfjorden or the Gipsdalen group, not primarily because it could be either, but because its submarine extension suggests a much larger development, which might merit its own group if more than one formation is defined. Lithologies. Limestones make up the bulk of the formation (95%). Medium-bedded biomicrites dominate at the top, which contain shaley and sandy partings or interbeds and a diverse brachiopod-crinoid-fusulinid fauna. These are underlain by red-weathering rubbly limestones with brachiopods. Below, the limestones are micritic and sandy, containing transported corals, brachiopods, crinoids, and fusulinids. Lower down there are several horizons with karst features infilled with coarse sandstone (terra rossa). In-situ Microcodium, possible root horizons, laminated stromatolitic limestone, calcrete, fenestrae and chicken-wire structure havc been noted. Here the fauna is poor and restricted with algae, ostracodes and small foraminifers. The sandy limestones pass downwards into homogeneous fine sandstone of variable thickness (up to 30 m). It appears to be unfossiliferous except for well developed root horizons in the middle of the unit. There is a pebbly, dark sandstone at the base of the formation. The thickness variations are possibly a result of the infilling of pre-Hambergfjellet Formation relief. Palaeontology and age. Anderson (1900) listed brachiopods from the upper part of the formation. Horn & Orvin (1928) recorded corals in the lower limestones which show an affinity with those of the Treskelodden Formation (B. T. Simonsen in the 1987 IKU Excursion Guide to Bjornoya ) and a rich brachiopod fauna was described by Gobbett (1963). Simonsen had mentioned the presence of crinoids and fusulinids in the upper beds and a restricted fauna of algae, ostracods and small foraminifera in the lower carbonates as well as root horizons in the basal sandstones. A variety of ages has been assigned to this formation. Fusulinids found in the upper part belong to the Sehwagerinajenkinsi zone which is Early-Middle Artinskian in age (Simonsen). Gobbett recorded a Sakmarian age on the basis of brachiopods, though he compared one brachiopod with an Artinskian species; and Bjoroy, Mork & Vigran (1980) stated that the brachiopod fauna suggests a Late Sakmarian or possibly Artinskian age. After a recent examination of the CSE collection, J.B. Waterhouse concluded that the upper beds contained very late Artinskian or Kungurian brachiopods, while the presence of Arculina in the basal part of the formation suggested an Artinskian or Sakmarian age at the oldest. Nakrem (1991) cofirmed an Artinskian age for the upper part of the formation from his study of conodonts.

1 !.4.3

Kapp Dun6r Formation (Gipsdalen Group)

The K a p p D u n & F o r m a t i o n , 75 m, consists m a i n l y o f dolostones a n d fusulinid-rich limestones. Sandstones a n d c o n g l o m e r a t e s f o r m m i n o r c o m p o n e n t s . In the lower p a r t o f the f o r m a t i o n , dolomitized palaeoaplysinid build-ups c o n t a i n i n g large b r y o z o a n colonies occur. In some places, the limestones show karst structures infilled by

r o o t - b e a r i n g c o n g l o m e r a t e , indicating periods o f sub-aerial erosion. Asselian deposition o f the f o r m a t i o n o c c u r r e d o n a m a r i n e shelf with open to restricted e n v i r o n m e n t s , p u n c t u a t e d by periods o f emergence.

Definition. The Kapp Dun6r Formation is a sequence of dolomites, it crops out on the west coast of the island and offshore to the west. It was described briefly by Horn & Orvin (1928) as the 'Fusuline Limestone'; they also listed the fossil identifications made by Anderson (1900). The term 'Kapp Dun& Formation' was introduced by Krasil'shchikov & Livshits (1974) and was used by Worsley & Edwards (1976). The detailed petrography of these sediments has been described by Folk & Siedlecka (1974) and systematically by Siedlecka (1975). There is no single type section. Several sections have been measured along the coast (Mork 1987), where the unit is up to 75 m thick. Both the upper and lower boundaries are present in a condensed section on Alfredfjellet. The formation lies stratigraphically below the Hambergfjellet Formation and this upper boundary, which is a strong unconformity, is exposed on Alfredfjellet where a condensed sequence of the Kapp Dun6r Formation crops out. The conformable base is taken at the transition from massive dolomites to the arenaceous deposits of the underlying Kapp Hanna Formation (Carboniferous). Lithologies. Massive to well-bedded dolostones with interbedded limestones are typical of this formation. Massive buff-weathering dolostones form 90% of the sequence. The upper part is dominated by dolomitized mudstones and two fusulinid-rich limestones, each with a distinctive fauna which makes them useful marker horizons (Simonsen in 1987, IKU Excursion Guide). Thin sandstone horizons occur in the middle part of the formation, associated with some sandy limestone, forming 4% of the formation. One sandstone is pebbly and upward-fining, lying on a microkarstic surface. Conglomerates are also a minor feature of the sequence. On Alfredfjellet, a coarse conglomerate overlies a karst surface and contains clasts of the underlying limestone which has a rich fauna dominated by fusulinids very similar to that of the upper fusulinid-rich limestone mentioned above. Both conglomerate and limestone contain abundant Microcodium. Three massive lenticular dolostones dominate the lower part of the formation, which are dolomitized palaeoaplysinid build-ups. In describing these reefs as frameworks Lonoy (1988) noted not only their wide extent but that they were related to karst features suggesting that they were at times subaerial. Dolomitization has left only ghosts of the original palaeoaplysinid framework. They contain large coral colonies, bryozoan 'thickets', stromotactic structures and local intraformationa] conglomerates. Stemmerik & Larssen (1993) shared the opinion of fluctuating sea levels with diagenesis leading to high porosity. Another conglomerate, half a metre thick, but wedging out laterally, occurs just above an infilled hollow in a build-up, containing roots. It is composed of a coarse sandy matrix and well-rounded pebbles as well as angular clasts derived from the build-up (Simonsen in IKU 1987). The carbonate build-ups are composite with superimposed structures. They have been sub-aerially exposed at several levels and show vugs and hollows infilled with laminated sediment containing root structures, karst and eroded surfaces. They pass laterally and upward into mudstones (lagoonal) which locally contain mudcrack horizons. At the top of the lower dolomite is a fusulinid-rich limestone with a distinct fauna, different from those of the upper two fusulinid-rich limestones (Simonsen in IKU 1987). Individual thin, highly bituminous beds occur with the porous biohermal structures (Bjoroy, Mork & Vigran 1983), comparable with the Brucebyen Beds of Spitsbergen. Interbedded with the dolostones are thin beds of biomicrite, partly dolomitized, which also appear higher in the section (forming 6% of the formation). They are a distinctive grey and contain fusulinids, corals, brachiopods and gastropods. Karst surfaces and marginal marine clastics are also present at some levels. The formation contains authigenic silica, replacing cement and/or fossils and forming nodules which occur as clusters resembling the chicken-wire fabric of evaporite nodules. In thin section they have a fibrous texture and contain ubiquitous minute sulphate inclusions which indicate that the silica has replaced sulphate (Folk & Siedlecka 1974). Palaeontology and age. Although the formation contains a moderately abundant fauna, including corals, brachiopods, gastropods, echinoderms and fusulinids, very few species have been described. Fusulinids have been useful in dating the formation (Simonsen in IKU 1987): Sphaeroschwagerina vulgaris?, which defined the Permian boundary in Russia and east Asia, is found in the uppermost part of the underlying Kapp Hanna Formation. Fusulinids from the lower fusulinid-rich limestones belong to the

SOUTHERN SVALBARD: BJORNOYA AND S U B M A R I N E GEOLOGY

Schwagerina arctica/Schwagerina (Daixina) sokensis zone. On the Russian platform, this zone is either late Gzelian or lowermost Asselian in age. The upper part of the formation contains distinct horizons with Sphaeroschwagerina mollieri and S. sphaerica, which are characteristic of the Late Asselian stage. The two upper fusulinid-rich limestones belong to the Asselian Schwagerina nathorsti/Schwagerina zone. Some fusulinids in the upper fusulinid-rich limestone indicate a close relationship with Early Sakmarian faunas, but a clear boundary between Asselian and Sakmarian faunas is not evident. Nakrem (1991) from conodonts concluded an Asselian age. The fusulinid-rich limestones at the top of the lower palaeoaplysinid dolomite contains a nearly identical faunas to that of the Brucebyen Beds on Spitsbergen with which it is correlated (Simonsen 1987).

11.4.4

Kapp Hanna Formation (Gipsdalen Group)

In c o n t r a s t to the overlying f o r m a t i o n s , the K a p p H a n n a F o r m a t i o n is a p r e d o m i n a n t l y a r e n a c e o u s unit. S a n d s t o n e s f o r m the b u l k o f the sequence, with smaller a m o u n t s o f i n t e r b e d d e d c o n g l o m e r a t e , d o l o s t o n e a n d shale. S a n d s t o n e s a n d c o n g l o m e r a t e s c o n t a i n rew o r k e d clasts d u e to e r o s i o n o f the u n d e r l y i n g u n i t as well as f r o m older sources. T h e s e d i m e n t o l o g y o f the f o r m a t i o n is c o m p l e x , w i t h variable facies. Overall, it represents m a r i n e , n e a r - s h o r e a n d floodplain e n v i r o n m e n t s , d e p o s i t e d o n an alluvial fan p r o g r a d i n g into a m a r i n e basin. It c o n t a i n s a varied f a u n a , w h i c h defines a K a s i m o v i a n - G z e l i a n age.

Definition. This is a distinctive arenaceous unit, previously known as the Yellow Sandstone (Horn & Orvin 1928; Cutbill & Challinor 1965). The present name was used by Krasil'shchikov & Livshits (1974) followed by Worsley & Edwards (1976). The formation crops out on the north and west coasts of the island, but no single section is typical because of faulting. The formation lies conformably below the massive dolostones of the Kapp Dun6r Fm. The base is erosional and is defined below a coarse conglomerate which marks a slight unconformity, beneath which lie carbonates and clastics of the Kapp Kgtre Fro. Lithologies. The formation consists of laterally variable alternations of conglomerates, sandstones, shales and dolostones. Sandstones form 75% of the sequence. They contain interbedded conglomerates (10%), micritic dolomites (10%) and thin, dark fossiliferous shales (5%). There is a general upward fining and a gradation through interbedded thin sandstone and dolomitic mudstone into the overlying carbonate-dominated Kapp Dun6r Fm. The sandstones are medium-grained, well-sorted, yellow-brown, and calcareous and commonly cross-bedded. Calcite, dolomite and celestine cements occur, generally giving the rocks a low porosity (Fig. 11.4). There is an 8-10 m basal conglomerate, red-brown in colour with clasts of vein quartz derived from pre-Devonian rocks, as well as cherts which are probably from the underlying Kapp KSre Formation. Conglomerates reappear interbedded with the sandstones. Analysis of sandstone mineralogy and conglomerate clast composition shows a well-developed inverse stratigraphy, reflecting progressive erosion of previously deposited sediments (Agdestein 1987). There is a dominance of pre-Devonian clasts in the southwest and Early Carboniferous clasts in northwestern exposures. The succession contains intraformational, erosional unconformities, of up to 5 degrees angular discordance. In addition, they may contain ravinelike channels up to 20 m deep, which are eroded into marine dolostone/shale sequences. These channels are filled with interbedded conglomerates and sandstones, which are partially cross-bedded and commonly have desiccation cracks on the bedding planes. Fissures filled with clastic material are another feature (Worsley et al. 1987). Palaeontology and age. Corals and crinoid stems were found by Holtedahl (1920) while Gobbett (1963) noted Linoproductus 6'19.Federowski (1975) described corals Worsley & Edwards (1976) reported corals, brachiopods and plants, but gave no further details. Agdestein (1987) mentioned corals, brachiopods, bivalves, fusulinids, crinoid fragments, trace fossils and plant debris. Corals in the lowermost conglomerates are the same as in the underlying Kapp Kfire Fm and are probably redeposited. Fusulinids from both parts of the Waeringella usvae zone have been reported by Cutbill and Challinor (pers. comm.) that indicate a KasimovianGzelian age. The Kasimovian-Gzelian age is supported by an Asselian estimate of the age of the overlying Kapp Dun6r Fm and by the underlying Late Moscovian Kapp Kfire Fm.

11.4.5

215

Kapp K~tre Formation (Gipsdalen Group)

T h e K a p p Kfire F o r m a t i o n is a c a r b o n a t e - d o m i n a t e d unit up to 1 7 0 m thick. T h e limestones are pale grey biomicrites, in places d o l o m i t i c a n d cherty. S o m e grey a n d red s a n d s t o n e beds a n d shales are i n t e r b e d d e d in the lower part. T h r e e m e m b e r s h a v e been defined. T h e (upper) Kobbebukta Member c o n t a i n s limestone, chert a n d cong l o m e r a t e c o n t a i n i n g c h a n n e l structures a n d small s y n - s e d i m e n t a r y faults. T h e Efuglvika M e m b e r consists o f c h e r t y biomicrites, a n d c o n t a i n s n u m e r o u s k a r s t surfaces a n d small, a n g u l a r u n c o n f o r m i ties, T h e (lower) Bogevika M e m b e r also s h o w s evidence o f sub-aerial erosion. It c o n t a i n s l i m e s t o n e s with d o l o s t o n e s , s a n d s t o n e s a n d shales. T h e overall d e p o s i t i o n a l setting o f the f o r m a t i o n was tidally influenced m a r g i n a l m a r i n e , affected by very variable relative sealevel c h a n g e s d u e to deltaic p r o g r a d a t i o n a n d subsidence, p r o b a b l y c o n t r o l l e d by local tectonics. Corals, b r a c h i o p o d s , fusulinids a n d o t h e r species m a k e up a rich a n d varied f a u n a a n d t h a t indicates a m a i n l y M o s c o v i a n age, a l t h o u g h a slightly wider t i m e - s p a n is possible as m a n y elements are n o t very age-diagnostic.

Definition. The Kapp Kfire Fm is a thick sequence of carbonates occurring in a fairly wide N-S belt in western Bjornoya. It is about 170m thick. It was originally described as the 'Ambigua Limestone' by Andersson (1900) and Horn & Orvin (1928). It was renamed the Kobbebukta Fm by Krasil'shchikov & Livshits (1974) with the Kapp Kgtre section as a type section, the Kobbebukta section being obscured by faulting. The upper boundary is taken at the thick extraformational conglomerate at the base of the overlying Kapp Hanna Fm which marks a slight unconformity above the intraformational conglomerates of the Kapp Kgtre Fm. The lower conformable boundary is marked by the underlying thick massive conglomerates of the Landnordingsvika Fm which contrasts with the carbonates (with thin intraformational conglomerates) of the Kapp KSre Fro. The formation consists mainly of limestones (85%), which are generally pale grey biomicrites. In the lower part grey and red sandstones and shales are interbedded. Corals and brachiopods are locally abundant and there are several oncolitic horizons. The limestones are dolomitic in places and are commonly cherty, especially towards the top of the formation. Two members were distinguished by Worsley & Edwards (1976), the upper Efuglvika Member and the lower Bogevika Mbr. Bjoroy et al. (1980), following the work of Kirkemo & Mork (1987), divided the Efuglvika Mbr into the Kobbebukta Mbr (upper-most) and Efuglvika Mbr. The Kobbebnkta Mbr thickens from 8 m at Kapp Kgtre in the southwest to about 45 m at the type section in the north. Erosion of the top, at the unconformity with the Kapp Hanna Fm, has caused this variation. It consists of limestones interbedded with massive intraformational conglomerates, containing chert and carbonate clasts. The latter often have channelled bases and show abrupt facies changes laterally. Small-scale syn-sedimentary faulting (along a WSW-ENE-trending scarp) has been observed, draped by the intraformational conglomerates. On the downthrown side, there is a sequence of shales and turbidites, the latter deposited by westward-flowing currents (Worsley et al. 1987). The Efug|vika Mbr is fully exposed at Efuglvika, where it reaches its maximum thickness of 80m, around Kapp KSre (70m) and also at Kobbebukta. It is dominated by thinly to massively bedded cherty biomicrites with an open marine fauna. The abundant chert occurs as nodules and 'dykes' and is of diagenetic origin. There are abundant karst and discontinuity surfaces and local small angular unconformities. Thin biomicrites are associated with the erosion surfaces. The karstic features seem to follow clear NE-SW trending zones of deformation and prominent large chert 'dykes' show the same general trend. The Bogevika Mbr lies conformably below, and in the type section at Landnordingsvika consists of about 90 m of limestones, interbedded with dolostones, sandstones and thin shales. Beds are generally greyish-red and greyish-green in colour, becoming paler and more grey towards the top, with more common biomicrite, in a transition to the overlying member. There are well-developed upward-coarsening rhythmic sequences from limestones to shale and sandstone in 3 - 8 m units. These typically show an upward transition from limestones and shales with a normal marine fauna of corals and brachiopods, to shales containing a more restricted fauna of bivalves, gastropods, ostracodes and plants. The upper contacts are typically sharp and may show either desiccation cracks, calcrete horizons or an erosional surface beneath the limestone or shale of the overlying cycle. Marked karstic and discontinuity surfaces are also relatively common within the limestones. Sandstones become less common upwards.

216

CHAPTER 11

Palaeontology and age. The limestones contain a rich fauna, of which brachiopods, corals and fusulinids have been described. Bivalves, gastropods, including Bellerophon (Anderson 1990), ostracodes and plants have been reported from the shales, but no details are available. Gobbett (1963) suggested, on the basis of brachiopods, a correlation with the Bashkirian/ Moscovian of the Moscow Basin. The fusulinids belong to the Wedekindellina zone implying a late Moscovian age (Cutbill & Challinor 1965). Work on corals from the formation (Fedorowski 1975) suggested that the fauna is transitional between Moscovian and Kasimovian.

11.4.6

Landnordingsvika Formation (Gipsdalen Group)

T h e L a n d n o r d i n g s v i k a F o r m a t i o n , 145-200 m is the lowest p a r t o f the G i p s d a l e n G r o u p in B j o r n o y a , a n d as elsewhere it is m a r k e d a n d i n d e e d characterized by the a p p e a r a n c e o f red-beds. It consists o f m a i n l y c o n g l o m e r a t e a n d s a n d s t o n e w i t h m i n o r m u d s t o n e s , in sequences. M o s t lithologies are r e d d e n e d , except for s o m e grey l i m e s t o n e s in u p p e r parts o f the sequence. T h e limestones c o n t a i n k a r s t surfaces a n d s o l u t i o n breccias, a n d a l o n g with d o l o s t o n e , chert a n d s a n d s t o n e they also a p p e a r as clasts w i t h i n the c o n g l o m e r a t e s . T h e s a n d s t o n e beds c o m m o n l y have erosive bases, a n d are crossb e d d e d a n d b i o t u r b a t e d . M u d s t o n e s o c c u r a b o v e the s a n d s t o n e s , especially lower in the f o r m a t i o n , a n d c o n t a i n desiccation cracks a n d rootlets indicating terrestrial d e p o s i t i o n . H o w e v e r , m a r i n e fossils o c c u r n e a r the t o p o f the f o r m a t i o n . This a n d o t h e r inform a t i o n indicates d e p o s i t i o n in a coastal setting, b u t m a i n l y o n an alluvial plain in semi-arid c o n d i t i o n s . F l o o d p l a i n , tidal-flat, coastal l a g o o n a n d offshore c a r b o n a t e facies are all represented. T h e f o r m a t i o n does n o t c o n t a i n a rich f a u n a a n d forms p r e s e n t d o n o t distinguish it f r o m the overlying f o r m a t i o n , suggesting an Early M o s c o v i a n a n d possibly B a s h k i r i a n age.

Definition. The Landnordingsvika Fm is a conglomeratic sequence up to 200 m thick occurring at the base of the Gipsdalen Gp in Bjornoya. It was named the "Red Conglomerate' by early workers (e.g. Anderson 1900; Holtedahl 1920; Horn & Orvin 1928), the present name being introduced by Krasil'shchikov & Livshits (1974) and adopted by Worsley & Edwards (1976). The type section is at Landnordingsvika. The upper boundary is conformable and transitional to the Kapp Khre Fm above. It is taken at the top of the uppermost distinct conglomerate below the carbonate-bearing sequence of the Kapp Kfire Fm. Carbonates appear almost immediately above. The base of the formation is taken at the boundary between the red beds and the underlying grey sandstones and conglomerates of the Nordkapp Formation (Billefjorden Group). The boundary is concordant but sharp in some localities (e.g. Krasil'shchikov & Livshits 1974), while at Kobbebukta there is a gradual passage over 10 20 m from coarse-grained sandstones of the Nordkapp Formation to finer red beds of the Landnordingsvika Formation. Similarly at Landnordingsvika, there is a transition to red beds over more than 60m (Horn & Orvin 1928). Lithologies. The formation consists of red conglomerates, drab sandstones and red mudstones, normally arranged in upward-fining cycles. Conglomerates form 50% of the section. They first appear about 40 m from the base and are most widespread in the middle part of the formation. They are generally red, of fine pebble to fine cobble grade. Sorting is variable, with a range from poorly sorted, matrix-supported conglomerates to well-sorted and grain-sorted conglomerates. Some show low-angle cross-bedding. Clasts consist of dolomite, limestone, chert and sandstone. The beds are cyclically arranged, commonly lenticular, with erosive bases. They tend to become finer upwards, passing into sandstones and red mudstones. Thick conglomerates are absent in the north. Red sandstones make up 40% of the sequence. Beds up to several metres thick occur throughout the formation in upward-fining cycles. Some beds in the lower part have erosive bases with intraformational conglomerates. The sandstones are moderately sorted, of coarse to very fine grain size and may show planar or cross-bedding. Flaser and lenticular bedding and bioturbation are found in some sequences. Towards the top of the formation, calcareous sandstone beds yield marine fossils. Grey bioclastic and micritic limestones appear also at higher levels, showing herring-bone cross-bedding and shallow channels with lag conglomerates. Karst surfaces with local solution breccias occur at the top of one of the carbonate sequences and the limestone has been strongly recrystallized, probably due to freshwater diagenesis (Gjelberg & Steel 1983).

Blocky, red and in places green mudstones make up 10% of the formation, occurring at the top of the sandstone in the upward-fining cycles, especially in the lower part of the formation, where they are dominant. Concretions, desiccation cracks and plant roots occur in places and marine fossils are absent in this facies. Palaeontology and age. A few fossils are found towards the top of the formation: brachiopods (Composita ambigua and Lingula), bivalve, crinoid and echinoid fragments, foraminifera and trace fossils of the Skolithos assemblage and ?Thalassinoides. These are indistinguishable from those found in the overlying Kapp Kfire Fm (Worsley & Edwards 1976). This fact, and the gradational contact between the two, suggests that the Landnordingsvika Fm is only slightly older, probably of Early Moscovian age, possibly extending to Bashkirian time (Gjelberg & Steel 1981).

11.4.7

Nordkapp Formation (Billefjorden Group)

T h e N o r d k a p p F o r m a t i o n , 2 3 0 m , is the u p p e r m o s t unit o f t h e Billefjorden G r o u p on B j o r n o y a , a n d is generally c o r r e l a t e d with the M u m i e n (Svenbreen) F o r m a t i o n o f the Billefjorden T r o u g h . N o f o r m a l subdivision o f the u n i t exists, but it can be split into an u p p e r a n d a lower unit. T h e u p p e r unit c o n t a i n s i n t e r b e d d e d c o n g l o m e r a t e , s a n d s t o n e a n d coaly shales. A t least three coal seams are also present, b u t they are laterally impersistent. Clasts in the coarser lithologies are quartzite, chert a n d quartzitic s a n d s t o n e . T h e lower unit c o n t a i n s thick c r o s s - b e d d e d s a n d s t o n e s with s u b o r d i n a t e m u d s t o n e a n d siltstone. T h e sandstones f o r m lenticular bodies a n d c o n t a i n s o f t - s e d i m e n t d e f o r m a tion features. It represents a b r a i d e d stream e n v i r o n m e n t within a n alluvial fan in p r o x i m i t y to an active fault. F i n e r - g r a i n e d units o f the u p p e r u n i t indicate the presence o f flood basins a n d lakes w i t h i n the fan. N o m a r i n e m a c r o f a u n a occur in the f o r m a t i o n ; a V i s e a n B a s h k i r i a n age is i n d i c a t e d by fusulinids. H o w e v e r , large depositional b r e a k s p r o b a b l y occurred, particularly at the b o u n d a r y b e t w e e n the u p p e r and lower parts.

Definition. This is the upper unit of the 'Ursa Sandstone' which was discovered when plant fossils of'Culm' (Early Carboniferous) age were found (Antevs & Nathorst 1917), which contrasted with the supposedly Devonian floras of the rest of the succession. It forms a quite distinct lithostratigraphic unit. Cutbill & Challinor (1965) gave the 'Culm' formational status, renaming it the Nordkapp Fm. They correlated it with the Svenbreen (Mumien) Fm in the Billefjorden Gp of Spitsbergen. No complete section exists, but Landnordingsvika provides a type section 120m thick; this increases to 230 m in the north. The formation dips to the west at 10-20 degrees, but in central and northern areas there is complex faulting. The upper boundary with the Landnordingvika Fm is conformable and, in some localities, transitional. It is marked by the upwards appearance of red beds. At Landnordingsvika, Worsley & Edwards (1976) defined the boundary as lying between the grey sandstones and conglomerates of the Nordkapp F m and the overlying red siltstones characteristic of the Landnordingvika Fm. However, Horn & Orvin (1928) and Gjelberg (1981) noted a more gradual passage at Kobbebukta. The lower contact with the Roedvika Fm is concordant, but Gjelberg (1987) noted that faults in the Roedvika Fm are truncated and overlapped by the sandstones of the Nordkapp Fro, which indicates a stratigraphic break. The massive sandstones of the Nordkapp F m can be distinguished and mapped separately from the sandstones with interbedded shales and coals of the Roedvika Fro. The formation consists of cross-bedded grey sandstones with subordinate conglomerates, rare shales and thin coals, which Gjelberg & Steel (1981) divided into two units, the upper containing more conglomerate and mudstone than the lower unit. The upper unit is exposed in the south at Landnordingsvika, where it is 65m thick. Thickness increases towards the northeast (Gjelberg 1981). It consists of intercalated conglomerates, fine- to coarse-grained sandstones and black coaly shales. The conglomerates are mostly matrix-supported and unsorted. Bedding structures are complex, with lenticular bedding, largescale planar trough cross-stratification and low-angle, almost horizontal stratification. Basal erosion surfaces are rare. Clasts are predominantly quartzite (45%), chert (35%) and red and grey quartzitic sandstone (20%). Red beds interfinger in the upper part in a transition to the Landnordingsvika Fro. Coal seams, 10-60cm thick, occur 15-40m below the

SOUTHERN SVALBARD: BJORNOYA A N D SUBMARINE GEOLOGY top, in a sequence of carbonaceous black shales with plant remains and rare pyrite nodules. They are thin and laterally impersistent. The transported plant remains and the absence of true seat-earths suggest that the coals are allochthonous. The lower unit is best exposed at Landnordingsvika in the south. It is dominated by monotonous cross-bedded sandstones with thin interbeds of mudstone and siltstone (1.6%). Sandstones are grey and white and quartzitic, with chert ctasts (more common than in the Roedvika Fm below). Heavy minerals include muscovite, biotite, pyrite, magnetite and ruffle. Ferruginous cement is common. Beds are lenticular, bounded by erosion surfaces and show large-scale, high-angle planar cross-stratification, trough cross-stratification and sub-horizontal stratification. Soft-sediment deformation features are common. Irregular beds and lenses of pebbly sandstone and conglomerate can be found in places. Palaeontology and age. Marine fossils have not been recorded, but the flora has been well documented. Several of the species present occur in, or are allied to, species in the Billefjorden Group of west and central Spitsbergen. They date the Nordkapp Formation as Early Carboniferous. There are six species and fifteen genera in common with the Aurita assemblage of Spitsbergen (Playford 1962, 1963) although some of the common genera, such as Densosporites, are rather wide ranging. Playford's original age-correlation for the Aurita assemblage was Visean and possibly Early Serpukhovian. On the basis of the known distribution of Diatomozonotriletes saetosus in Britain (Smith & Butterworth 1967), which may perhaps be restricted to Late Visean, Kaiser (1971) gave a Late Visean age for his assemblage, also found in the upper part of the formation. The lower part of the formation may span the Tournaisian/Visean boundary as a Late Tournaisian age coal seam crops out south of Ellasjoen, which probably belongs to this formation, though Kaiser (1970) suggested it belonged to the Roedvika Formation. Lack of biostratigraphical control makes age correlations difficult, and the presence of conglomerates may conceal one or more disconformities. Gjelberg (1981) considered that there was a dramatic change in deposition between upper and lower units, which may well reflect a break. As there is a transition to the Moscovian (and possibly Bashkirian) Landnordingsvika Formation above, the Nordkapp Formation may span Visean-Bashkirian time. Worsley & Edwards (1976) suggested a break in deposition at the top of the formation, following Krasil'shchikov & Livshits (1974) in considering the junction to mark an abrupt change in lithology. This seems unlikely in view of the transitional nature of the boundary elsewhere.

11.4.8

217

The upper boundary is concordant with the overlying Nordkapp Fm, but Gjelberg (1987) suggested that the boundary probably represents an unconformity, as Early Carboniferous faults are apparently truncated and overlapped by the Nordkapp Fm. The junction can be mapped at the base of the massive Nordkapp Fm sandstones which overlie interbedded shales, sandstones and coals of the Roedvika Fm. The base is unconformable, lying on metasediments of Late Precambrian to midOrdovician age (Fig. 11.5). The formation consists of shales, sandstones and conglomerates in varying proportions. The thicker northeastern development has been divided into three members (Worsley & Edwards 1976); the upper and lower are coal-bearing and separated by a middle more sandy member. (3) The Tunheim Mbr, 80 m has no complete section exposed, it consists of grey sandstones and shales, with local conglomerates and coals. The sandstones are quartzitic, cross-stratified and flat-bedded. Upward-fining cycles, with sandstones 5 25 m thick are clearly present. Plant fossils, which are abundant, have been reduced to coaly shale and ferrous minerals; underclays are developed. The top of the member is predominantly shale, which contrasts with the base of the Norkapp Formation. Coal-bearing shales appear about 20 30m below the top with three main seams. The lower 'A' seam is the thickest, varying from 90 to 150 cm. The 'B' and 'C' coals are much thinner (40-50 cm) and less persistent than the 'A' seam and may be eroded laterally by channelling at the base of the overlying sandstones. This is especially the case with the 'C' seam. These beds are underlain by a variable sequence of sandstones and shales. The upper shales of this unit thicken northwards and there is visible splitting of the coal seams. The lower 30 m are composed of three or four sandstone sequences, each eroding into the base of the one below. The Rifleodden Conglomerate Bed is a locally developed unit which occurs within approximately 20 m of the base of the member. It makes a useful marker. (2) The Kapp Levin Member, 80 m is of grey cross-stratified sandstones and conglomerates. Shales are rare except for a 10m shale sequence that forms the top of the unit. There are no well-developed coals seams. (1) The Vesalstranda Member, 200 m marks the occurrence of the finegrained lithologies. At the top, the member consists of 6 0 - 8 0 m of black shales and commonly coals, with some sandstone horizons (the Misery Series of Horn & Orvin 1928). The lower 180 200 m consists predominantly of grey and purple sandstones and shales in units up to 25m thick. The shales contain abundant plant fossils, and underclays are developed.

Roedvika Formation (Billefjorden Group)

A t the base o f the Billfjorden G r o u p o n B j o r n o y a , the R o e d v i k a F o r m a t i o n , 360 m, is a clastic sequence. T h e base, a n d possibly also the top, are u n c o n f o r m a b l e ; it rests o n P r e c a m b r i a n a n d O r d o v i c i a n b a s e m e n t , it has b e e n divided into three m e m b e r s , consisting o f s a n d s t o n e s , shales a n d c o n g l o m e r a t e s , w i t h m i n o r coal seams. T h e u p p e r ( T u n h e i m ) a n d m i d d l e ( K a p p Levin) m e m b e r s consist m a i n l y o f c r o s s - b e d d e d s a n d s t o n e s a n d c o n g l o m e r a t e s , a l t h o u g h the u p p e r m e m b e r also c o n t a i n s coal. T h e lower (Vesalstranda) m e m b e r is m a i n l y fine-grained, c o n t a i n i n g coal, a b u n d a n t p l a n t debris a n d also fish scales. T h e f o r m a t i o n was d e p o s i t e d in lacustrine, deltaic a n d fluvial e n v i r o n m e n t s , w i t h channel, crevasse splay, lev6e, f l o o d p l a i n a n d m o u t h - b a r deposits all represented. T h e overall u p w a r d c o a r s e n i n g , at least in the lower h a l f o f the f o r m a t i o n , suggests infilling o f a basin d u e to alluvial fan p r o g r a d a t i o n . P l a n t fossils at the base o f the f o r m a t i o n , t o g e t h e r with m i o s p o r e s , are c o n s i d e r e d typical o f D e v o n i a n flora, a n d d a t e the V e s a l s t r a n d a a n d lower K a p p Levin m e m b e r s as F a m e n n i a n . This is c o n f i r m e d by fish scales p r e s e n t in t h o s e units. T h e rest o f the f o r m a t i o n is o f T o u r n a i s i a n age.

Definition. The lower part of the 'Ursa Sandstone' of Horn & Orvin (1928) was defined as the Roedvika Fm by Cutbill & Challinor (1965), who included it in the Billefjorden Gp. It includes the Tunheim Series, the Flozleere Sandstone Series and the Misery Series of Horn & Orvin (1928) which have been redefined as the Tunheim, Kapp Levin and Vesalstranda mbrs respectively (Worsley & Edwards 1976). It crops out mainly in the east of Bjornoya and is about 360 m thick in total, but there is a general thinning to the south and southwest to only 100 m (which is also seen in the overlying Nordkapp Fro).

Fig. 11.5. Structure contour map of the base of the Roedvika Formation, with diagrammatic profile (from CSE observations),

218

CHAPTER 11

Boulder conglomerates of variable thickness occur locally at the base, which is unconformable on the pre-Devonian basement. Gjelberg (1978) reported a facies analysis of the coal bearing strata. Palaeontology and age. The plant fossils from the Roedvika Formation have been regarded as the typical flora of Late Devonian time. Nathorst (1902) correlated it with the Late Devonian rocks of Ireland and Belgium on the basis, particularly, of the occurrence of Archaeopteris, Roemeriana and Cyclostigma (Bothrodendron) kiltorkense which occur in the Tunheim Member. Sen (1958) reported on Nathorst's Late Devonian megaspores. In a study of the distribution of lycophyte species, Schweitzer (1969) also considered Cyclostigma kiltorkense to be Devonian, but he observed a 'floral break' between the Vesalstranda Member and the Tunheim Member. This is reflected in the detailed studies of miospore assemblages by Kaiser (1970, 1971) which suggest that the Vesalstranda Member and lower Kapp Levin Member are Famennian in age and the upper Kapp Levin and Tunheim Members are Tournaisian. Kaiser (1971) distinguished three distinct, though transitional, microfloral assemblages in the Vesalstranda and Kapp Levin members. He considered these three assemblages to be distinctive, contrasting with the assemblages characterising the overlying Tunheim Member and Nordkapp Formation. By comparisons with North American, Russian and Belgian sections, he showed that they have a Late Famennian age. The Famennian-Tournaisian boundary must be in the unfossiliferous upper part of the Kapp Levin Member. Thus the Kapp Levin Mbr seems to span the Devonian-Carboniferous boundary. Kaiser (1971) recognized three other distinct assemblages of Early Tournaisian, Late Tournaisian and Late Visean age. The two Tournaisian assemblages occur in the Tunheim Mbr and the Visean one occurs in the overlying Norkapp Fm (see above). The only fauna found is from the basal conglomerates of the Vesalstranda Member. It consists of fish scales of Holyptychius nobilissimus AG, H. giganteus AG and H. sp. ~f americanus Leidy, and one form belonging to the Asterolepidae (Holtedahl 1920). The occurrence of Holoptychius indicates a Late Devonian age.

11.5

Pre-Devonian strata of Bjornoya

In the south of the island older rocks are exposed beneath Late D e v o n i a n - E a r l y C a r b o n i f e r o u s cover. They were first noted by Nordenski61d in 1864 (Dun~r & Nordenski61d 1867) w h o correlated the dolostones and limestones with those at M t Hecla. On Nathorst's 1898 expedition Andersson found fossils identified as Ordovician (Lindstrom 1899) who described three members: (3) red and green slates, (2) dolomite and quartzite sandstone, (1) dark limestone with Tetradium. Holtedahl (1920) found Ordovician fossils in the dolostones underlying the Tetradium Limestone and his succession was quoted by Horn and Orvin (1928) thus: (4) Tetradium Limestone (340 m) Ordovician (3) Younger Dolomite Series (2) Slate Quartzite Series. (1) Older Dolomite Series, the upper parts being more arenaceous and lower with oolites, pisolites and stromatolites. In spite of the conspicuous thrusts, the upper (sandy) part of the Older Dolomite Series was reported as transitional to the overlying Slate Quartzite Series. Krasil'shchikov & Mil'shtein (1975) redescribed with 'suite' (formational) names as follows: Ymerdalen Fm Limestone Mbr (mid-Ordovician) Dolomite Mbr (Canadian) TECTONIC CONTACT Sorhamna Fm: Slate Quartzite Series UNCONFORMITY Russehamna Fm: Older Dolomite Series Harland, Hambrey & Waddams (1993) from CSE 1986 and 1987 in particular noted the relations of Sorhamna and Russehamna formations and combined them in a new Bjornoya Group. Armstrong & Smith (in press) from CSE fieldwork in 1986 and based on investigations of conodonts in the Ymerdalen Formation formalized the two original units with new names thus:

Antarcticfjellet Formation (= Tetradium Limestone) Perleporten Formation (= Younger Dolomites) and consequently the Ymerdalen Formation was raised to group rank. The formal classification of p r e - D e v o n i a n strata currently stands as follows.

Ymerdalen Group (Krasil'shchkov Livshits 1974) Antaretiefjellet Formation (Holtedahl 1920; Armstrong & Smith in press) Perleporten Formation (Holtedahl 1920; Smith & Armstrong in press) Bjornoya Group (Harland, Hambrey & Waddams 1993) Sorhamna Formation (Holtedahl 1920; Krasil'shchikov & Livshits 1974) Russehamna Formation (Holtedahl 1920; Krasil'shchikov & Livshits 1974).

11.5.1

Ymerdalen Group

Antareticfjellet Formation ( : T e t r a d i u m Limestone), 93 to 180m. This unit occupies the central part of the outcrops of older rocks and forms the rugged barrier of the blackish hills of Antarcticfjellet. H o r n & Orvin (1928) described the rock as d a r k grey with thin and white calcite veins. Large masses of Iceland spar are f o u n d near faults and east o f Ellasjoen in a vein with barite. The limestone is fine-grained 0.005 to 0.01 ram, and the larger calcite crystals m a y attain a d i a m e t e r of 10cm. The calcite crystals are interlocked. A r m s t r o n g & Smith (in press) n o t e d b u r r o w - m o t t l i n g in the grey fine m u d s t o n e s a n d wackestones. The middle part is thicker bedded, d a r k weathering and rich in crinoid ossicles and gastropods. Fossils are common about 120 m up from the base where Holtedahl (1920) reported a middle Ordovician (Black River) fauna. Tetradium cf. syringoporoides Ulrich, several species of bryozoans, crinoid ossicles, Rafinesquina sp., Maclurites sp., Orthoceras (Kionoceras?) sp., Endoceras (Vaginoceras?) sp., Endoceras? sp., Actinoceras bigsbyi Bronn (= A. tenuifilum Hall?), Gonioceras (occidentale Hall?) sp., Gonioceras nathhorsti u.sp. Armstrong & Smith (in press) added conodont records of low abundance but high diversity and including many unnamed taxa previously known only from Greenland and the Canadian Arctic. The macro- and micro-fauna together indicate that the base of the formation is of earliest Black Riveran (or latest Whiterockian) age and the youngest dated horizon is no younger than Black Riveran (latest Llanvirn or early to mid-Caradoc (Armstrong & Smith in press). The Antarcticfjellet (limestone) Formation appears to pass down conformably into the Perleporten (dolostone) Formation. Precise correlation with sections in N o r t h Greenland, is possible and shows that the f o r m a t i o n is equivalent to the B o r g u m River F o r m a t i o n (M. P. Smith in press). The estimated age of the base of the f o r m a t i o n is earliest Black River (or latest Whiterockian) and the youngest dated horizon is no y o u n g e r than Black River, i.e. latest Llanvirn or early to m i d - C a r a d o c .

Perleporten Formation ( : Y o u n g e r Dolomite), 250 to 400 m. Was described by H o r n & Orvin (1928) as a m o n o t o n o u s sequence of grey dolostone, weathering yellowish and forming steep sea cliffs. Generally it rests horizontally except near overthrusts where dips steepen. It is sandy, in the basal part where it u n c o n f o r m a b l y overlies the S o r h a m n a F o r m a t i o n . The new name is from the opening in the steep cliffs west of the anchorage at Sorhamna; no through section is available (Armstrong & Smith, in press). The upper part contains structureless bedded (1 20 cm) lime mudstones and dolostones. The middle part is poorly exposed. The base of the unit is of buff-weathering sandy dolostones with quartz sandstone beds about a metre thick, with cross lamination. Armstrong & Smith reported dolomicrite rip-up clasts, some being imbricated. Some thicker beds show dewatering structures and the overlying dolostones are not sandy, they contain black chert nodules. Holtedahl found fossils 250 m below the overlying Tetradium limestone including: Calathium, Archaeoscyphia and Piloceras and Ceratopea which date the horizon as Canadian (Early Ordovician). Armstrong & Smith (in press) reported that conodonts were few; only one sample, 60 m from the top, yielded identifiable forms: Paraprioniodus

SOUTHERN SVALBARD: BJORNOYA AND SUBMARINE GEOLOGY (Mound) and 'New Genus 4' of Ethington & Clark (1982, fig. 6), 'indicative of the holodentata-harrisi biozones (latest Early-Middle Whiterockian)' i.e. late Arenig to early Llanvirn. costatus

11.5.2

Bjornoya Group

Sarhamna Formation. This formation contrasts with the competent carbonate units above and below, consisting of red and green slates, often folded with well-developed cleavage, with beds of quartzitic sandstone. The sandstones which are only a minor constituent, are fine-grained (quartz 0.1-0.2mm) some with magnetite cement with cores of pyrite and accessory tourmaline, zircon and rutile. Others show interlocking grains with feldspar, pyrite, apatite, zircon and sericitic mica. (Horn & Orvin 1928). Harland & Wilson (1956) had suggested that the two older formations (Sorhamna and Russehamna) might be correlated respectively with the Polarisbreen and Akademikerbreen groups of Ny Friesland, thus making the Sorhamna Formation Vendian. Harland, Hambrey & Waddams (1993) confirmed that there need be no unconformity beneath the Sorhamna Formation which crops out at Sorhamna, Kvalrossbukta and Roedvika on the coast and inland where it overlies the Russhamna Formation and is unconformably overlain by the Late Devonian Roedvika Formation. They also concluded that the Perleporten Formation (Ymerdalen Group) lies unconformably on the Sorhamna Formation along the poorly exposed contact inland west of Russehamna. The basal Perleporten strata were recorded by A. P. Heafford and P. Smith as sandy and containing large clasts of dolostone. W. B. H noted, on the north cliff of Russelva a large fissure with the overlying formation sediments penetrating the Sorhamna Formation. The southern outcrop has clean wave-worked cliffs at Sorhamna and Kvalrossbukta and in each locality angular carbonate lonestones of 1-2 cm diameter occur within a slaty matrix. The slates are green and patchily red and grey. They could represent marine muds with an ice-rafted component in the grey facies. The red facies are similar to distal turbidites with lamination and load structures.

Russehamna Formation. Holtedahl (1920) had correlated this 'Older Dolomite Series' with the Porsanger Dolomite of northern Norway which, he thought to be Ozarkian or late Cambrian to Early Ordovician. It is a distinctive, somewhat variable unit with five members as described by Krasil'shchikov & Mil'stein (1975). Species of the assemblages are listed in Section 13.3.4 under the heading Vendian biotas. Member (5), 10-20m grey massive sandy dolostone with relict phytolithic texture, in isolated outcrops to the NE (west of Roedvika). Member (4), 150-200 m light grey dolostone with quartz sandstone laminae; transitional to member (3). At the bottom is assemblage IIIa of microphytoliths. Member (3), 80-120m grey fine-grained dolostone with up to 5% quartz grains near top with 'conglomerate texture'. Member (2), 50-80 m alternating units (4 6 m) grey massive dolostone and finely laminated dolostone with iron-stained partings. The bottom 15-20 m is a distinctive marker-bed with assemblage II: Member (1), 150m grey medium-grained dolostone with assemblage I near top. Assemblage IIIb compares with Yudoma assemblages i.e. Vendian and a less identifiable assemblage in Member (5) could be similar. Krasil'shchikov & Mil'shtein argued that assemblages II and IIIa are similar to each other in age and to the upper Riphean of Zhuralev (?Sturtian) and that assemblage I is probably older. Thus the upper part of Member 3 and Members 4 and 5 are probably Vendian. The unconformity postulated above Member 5 would suggest that the Sorhamna rocks are significantly younger, but that break has not been confirmed. On the other hand correlations on such a biota are not accepted as reliable by some authorities (e.g.N. Butterfield pers. comm.).

11.6

219

Structural sequence of Bjarnoya

The sequence of Bjornoya strata divides naturally into three and these three divisions are labelled, for convenience in this section only, as basement, cover and platform. The following discussion is arranged accordingly. Within each of the three sequences are disconformaties and even a marked angular unconformity. In brief: the Platform resting unconformably on a peneplane is hardly deformed being only tilted and cut by minor faults; the cover sequence within it records some mobility in sedimentary environments and is itself folded and cut by faults which appear to be truncated by the Platform unconformity; the basement was folded and thrust-faulted by a more intense (Caledonian) tectonism. These strata are mostly truncated by the cover and exceptionally by the platform sequence. Lepvrier, Leparmentier & Seland (1989) discussed the fault regimes of Bjornoya in relation to those of Svalbard generally.

11.6.1

The basement

Within the basement succession it appears that the Russehamna and Sorhamna strata may be conformable and even transitional. An unconformity is locally evident between the Sorhamna and Perleporten formations but most contacts are tectonic so its nature cannot be established. There would appear to be a Cambrian hiatus. On the other hand, the basement formations were together subject to intense tectonism between early Caradoc and Late Famennian so spanning part of Late Ordovician, all of Silurian and most of Devonian time. By analogy with Spitsbergen, this would exclude affinity with the west Spitsbergen terranes where significant midOrdovician tectonism is evident, but would fit the central and eastern terranes and so may broadly be classed as Caledonian. However, the lack of Cambrian strata as well as the distinctive biotas would appear to distance Bjornoya from the other Svalbard terranes. At the same time the close affinity with successions in eastern North Greenland (Smith & Armstrong 1997) are more promising. The dominant feature of these basement structures is of overthrusting to the west or W N W . This contrasts with the opposite vergence seen in the Hornsund region of south Spitsbergen in the Central Terrane. Since Holtedahl's early work and the geological survey of Bjornoya by H o r n & Orvin (1928) (Fig. 11.6)it is evident that the Older Dolostone Series dip 35 ~ to 40~ at Russehamna, more steeply at Sorhamna and even vertical in M~keholmen, the island marking the eastern barrier to Sorhamna. Seen from the south, the cliff sections show that these more competent older rocks thrust westwards over the younger rocks facilated by the incompetent Sorhamna slates which received their more acute folding and cleavage in this process (Fig. 11.7). Indeed the western boundary of the Russehamna dolostone is generally faulted. The dolostone is traversed by reverse faults that tend to strike N W - S E to N N W - S S E . The Perleporten dolostones are relatively flat-lying except for some folding adjacent to the above overriding thrust masses. Some further structures are listed below. (1) Strong cleavage is noticeable close to the thrust surfaces. The dolostones and limestones have been deformed by numerous fractures and several reverse faults that repeat the sequence. (2) The thrust faults exposed in the Sorhamna and Kvalrossbukta area dip eastwards. One such thrust can be traced from Sorhamna northwards to Kvalrossbukta where it is folded and the dip decreases from 45~ to 20~ consequently the thrust has a sinuous outcrop pattern. (3) Thrust faults have also been recognized in Ymerdalen, deforming the Ymerdalen Formation, and repeating the strata. Although these thrusts are not exposed their eastward dip had been determined on the basis of topographical constraints, but the amount of dip is indeterminable from our present knowledge. Even though the thrusts have a straight mappable trace this does not necessarily indicate a steep dip because of their position in the valley bottom. Other thrust faults are exposed or can be inferred by stratigraphic repetitions where there is good exposure in the river valleys, in particular along Russelva and Orvella.

220

CHAPTER 11 I 18~

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Because only the basement is mineralized it could be argued to be a concomitant effect of the E - W compression with corresponding N - S extension. Alternatively a sinistral Svalbardian strike-slip phase within the same tectonic interval could be responsible. Even Tertiary dextral strike-slip cannot be ruled out. At least one factor must be the composition of the deeper basement which appears to favour an eastern North Greenland connexion.

11.6.2

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STRUCTURAL MAP OF BJORNOYA (Simplified from G. Horn & A.K. Orvin, 1928)

Pre-Devonian strata

Fig. 11.6. Schematic structural map of Bjornoya (simplified from Horn & Orvin 1928). (4) The strata generally have a N-S strike and the bedding generally dips eastwards (except where steeply folded). Greater dips (30~ <') occur in the exposures along the east coast around Sorhamna and Russehamna. Fold axes generally have a N-S to NE-SW trend and their axial planar cleavage generally has a moderate eastward dip, which is consistent with a fold vergence to the west and with sinistral transpression on N S faults. These features are matched in eastern North Greenland. (5) Metamorphism and cleavage development within the slates of the Sorhamna Formation appears to be either contemporaneous with, or earlier than, the thrusting. (6) The difference in structure between the Ymerdalen Formation and the older Sorhamna and Russehamna formations is thought to be due to a competence contrast and was not caused by two tectonic events as suggested by Krasil'shchikov & Livshits (1974). (7) E-W-trending, steeply dipping faults have also deformed the basement strata, these could be described as transfer faults. (8) The eastward dip of the thrust faults and axial planar cleavages suggests that the basement has been overthrust from the east. These structures must thus lie above a detachment surface which dips eastward. However, the reliability of this conclusion is limited by the small area of exposed basement on the island. (9) The evident westward verging Caledonian deformation and the contrast with Spitsbergen terranes favour the opinion of Smith (in press) that Bjornoya then was part of eastern North Greenland. Metamorphism in the presumed Caledonian Orogeny was not sufficiently intense to produce phyllites. Ritter et al. (1996) from zircon fission-track data found that the maximum temperature was less than 290~ Mineralization is evident in the basement. Galena, discovered in 1630 occurs with sphalerite and barite and was mined from 1925 to 1930. 75 tons were shipped in 1926. The veins strike E - W in both Younger and Older Dolomites (Flood 1969).

The cover sequence

This sequence comprises seven formations (from Reedvika to Hambergfjellet) so spanning Late Famennian to Sakmarian time. There is one evident disconformity between the Kapp K5re and Kapp H a n n a formations and a marked angular unconformity beneath the Hambergfjellet formation. These structural indications of instability within the sequence are greatly reinforced by the frequent conglomerates. Lepvrier, Leparmentier & Seland (1989) described the sequence of faulting regimes in three or four phases during this cover sequence. Such evidence of diastrophism is hardly surprising, because the island occupies a position somewhat less remote than Late Paleozoic Spitsbergen from the Hercynian-Appalachian or,genies and yet which hardly affected Spitsbergen which was then north of eastern North Greenland. The basal Roedvika unconformity is non-planar and may indicate that deposition followed the earlier deformation without adequate time for peneplanation. Part of the curvature is, however, a later distortion. It truncates the Caledonian structures and the following four formations appear to be concordant. Nevertheless the successions are punctuated by conglomerates: the Rifleodden Conglomerate within the Tunheim Member of the Roedvika Formation; conglomerates in the Nordkapp and Landnordingsvika formations. Moreover, Gjelberg (1987) noted that faults in the Roedvika Formation are truncated by the Nordkapp Formation basal unconformity. Lepvrier et al. identified an E - W extensional phase related to a N-S-trending half graben during Nordkapp and Landnordingsvika time. The Landnordingsvika Formation comprises 50% conglomerates at about seven intervals in the upper half. Gjelberg (1981) postulated that the conglomerate wedges developed from an intermittently rejuvenated fault scarp so that there was land immediately to the west. This scenario may well have been initiated in Nordkapp time. The Kapp Kgtre Formation, the upper unit in this sequence, is not only conformable but its carbonate facies perhaps indicates more stable conditions (BashkiriamMoscovian time) except in the Kobbebukta member conglomerates. These and the following coarse conglomerate of the Kapp H a n n a Formation resting somewhat unconformably on the Kapp Kglre Formation (with 10% interbedded conglomerates) relate to the second diastrophic episode of Lepvrier et al. This is an E N E - W S W compressional phase corresponding to basinal inversion. This is documented by dextral N E SW and sinistral E W strike-slip faults interpreted as Riedel fractures of the main N S transcurrent fault zone. This was followed by a N N W - S S E to N S dextral transtensional regime, an instability which persisted through Kapp Dun6r Formation time and ceased before deposition of the Hambergfjellet Formation. The Kapp Dun6r Formation follows conformably. It is essentially dolostone indicating relatively more stable conditions. The top of the formation is marked by a strong unconformity, indicating not only erosion but some condensing of the deposits beneath the Hambergfjellet Formation. Indeed the Hambergfjellet Formation elsewhere oversteps with a basal pebbly sandstones almost all earlier formations so marking a distinct diastrophic episode of approximately late Rotliegendes age. The nature of the Hambergfjellet events is known only from its limited outcrop in the southwest of the island so that elsewhere it is not clear how much of the pre-Platform deformation took place in pre-Hambergfjellet times. Its steep dips however indicate that

SOUTHERN SVALBARD: BJORNOYA AND SUBMARINE GEOLOGY

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diastrophism continued into the pre-platform interval. This interval represents approximately (Artinskian) time, say 10 million years9 Its group status is thus delayed. The m o v e m e n t s preceding the platform sequence appear to cut and d e f o r m strata t h r o u g h o u t the island. The structure generally trends N - S . The faulting appears to be consistently extensional (E-W), i.e. seen as n o r m a l dip-slip faults. The most accurate sections

are those by H o r n & Orvin t h r o u g h the T u n h e i m coalfield. After this a nearly continuous sequence of cliff sections as seen from the sea were recorded by a Cambridge party in 1986. Inland the faults are not so easily characterized, with so few g o o d sections 9 Strata dip up to 35 ~ also with N~S strike. At least two of the faults also cut the b a s e m e n t and it is not clear as to whether these were original faults which were rejuvenated and

222

CHAPTER 11

if so it could well apply to others. In this case also such faulting would have post-dated the thrusting episode. On the other hand the faulting could have been initiated in late-cover-pre-platform time. Krasil'shchikov & Livshits (1974) referred to a very broad fold structure as the Bear Swell which was indicated as an anticlinal axis approximating through the maximum N-S length of the island. Supporting this view is the appearance of the basement in the centre south and the eastward younging with dips averaging 50~ The structure whatever its nature must have been peneplaned before the platform sequence. The Swell was said to be bounded by synclinal axes: the Kapp Dun6r Syncline to the west and the Framnes Syncline to the east in each case right on the coast so that little can be seen of the synclinal structures. Mention must be made of the opinion of Krasil'shchikov & Livshits (1974) that the contrasting thicknesses within the Roedvika Formation (100-360m in a distance of less than 12km) must indicate that the cover sequence, as here defined, must have been thrust as a nappe over the basement. No other supporting evidence for this suggestion has been offered. Differential subsidence of 260m in say 10km (a gradient of 2.6% or less than 1~ r) developing over say one million years would give neigbouring subsidence rates of 0.1-0.36 mm a -1. In a deltaic environment with observed local curvature of the base of the formation (as shown in Fig. 11.5) greater contemporaneous differential subsidence could be accommodated.

11.6.3

The platform sequence

The unconformity beneath the Miseryfjellet Formation is marked by a basal conglomerate. However, its typical Kapp Starostin facies indicates that in this later Permian episode Bjornoya shared the stable shelf environment with the rest of northeastern Laurentia, and in contrast to the developing Uralian Orogeny. Also as in Spitsbergen there is only a minor disconformity with the following and contrasting Triassic argillaceous facies. According to the map by Horn & Orvin (1928) and modified by Cambridge work in 1985 and 1986 many faults can be shown to be pre-Miseryfjellet Formation. The presumption is that other similar faults in earlier strata where the platform sequence has been removed by erosion also belong to this pre-Platform faulting episode. The platform evidently followed peneplanation and rests on a uniform, almost plane, surface that dips to the north, so that the unconformity is only just above sea level at Nordkapp, and in the extreme south where it caps the cliff tops. It is at an intermediate height at Miseryfjellet. This indicates a northern dip of about 1~ (to 3~ max) reduced by occasional small E-W faults with downthrow to the north (Horn & Orvin 1928). The unconformity laps on to Kapp Kfire, Landnordnigsvika and Nordkapp formations in the north and in the south onto Roedvika and the basement formations.

1 |.6.4

Post-platform structure

Bjornoya, since Triassic time has been subjected to little deformation. Most conspicuous are land-slips especially at southeast Miseryfjellet and northeast Hambergfjellet which can at first confuse both structural and stratigraphic interpretations. There is no indication of the Paleogene West Spitsbergen Orogeny. The highest temperatures recorded were 160~ in the platform sequence (Ritter et al. 1966).The date of the northward dip and the E W faults with downthrow to the north is uncertain. The maximum eroded overburden was between 2900 and 4200 m (Ritter et al. 1996).

11.7

Submarine outcrops

Elverhoi & Kristoffersen (1978) described Holocene sedimentation to the southeast of Bjornoya which masks the underlying solid outcrop and tends to fill in depressions. Predominantly glacial

sediments, presumably mainly from floating ice, are being winnowed so forming a lag deposit to a depth of about 150 m. Between 150 m and about 480m relatively undisturbed diamictite was dredged. At greater depths, generally in depressions, finer sediments occupied the surface layers. Presumably this finer product of winnowing covered the ubiquitous glaciomarine deposit. In the immediate neighbourhood of Bjornoya the solid outcrop pattern was tentatively extrapolated up to about 8 km by Gronlie, Elverhoi & Kristoffersen (1980). Within this offshore area they measured seismic velocities of the principal rock units of Bjornoya and checked them against some onshore determinations, also obtaining porosity measurements. This work forms the basis of the diagram (Fig. 11.4) which was modified as explained in the caption. Interpretation of seismic data suggested a relatively simple subcrop map to Mork & Fanavoll (in the 1987 Excursion Guide to Bjornoya) with a small area of basement to the southeast. The dominant Bear Swell of Krasil'shchikov & Livshits is marked by an extensive outcrop of Billefjorden Group rocks to the east and north, ringed in roughly oval pattern by successively younger later Paleozoic strata, and complicated by postulated faults to the south. This is consistent with Bjornoya occupying a position on the Stappen High (see below). 'High resolution seismic stratigraphic data from the Bear Island fan' is the subject of a study by Laberg & Vorren (1995). This fan is one of the major submarine features of the western Barents Shelf where much of the area between Spitsbergen and Bjornoya was drained over the continental slope. Late Pleistocene debris flows up to 50m thick, 20kin wide and over 100km long, were probably derived from glacigenic deposits formed during glacial maxima. The hydrocarbon potential of the Bjornoya West Province was outlined by Rasmussen, Skott & Larsen (1995). This work summarised the offshore Tertiary stratigraphy and tectonic sequence, partly based on an exploration well in 1992. Two Paleogene tectonic episodes were identified. The first correlating with Early Eocene opening of the North Atlantic, with extensional NE SW-trending faults and possibly N-S strike-slip faults, accompanied by volcanic activity associated with the young ocean crust. Mid- to Late Eocene erosion of the Stappen High resulted in deposits in the Bjornoya West subsiding basin. The second episode was when Late Eocene to Early Oligocene structural features developed. Neogene and Quaternary thick post-rift deposition on the continental margin followed with the greatest volume being Pliocene through Pleistocene, augmented by glacial activity. All the structural evidence was of normal faulting without any compressive component being recorded.

11.8

Submarine structure

The main structural elements of the area are shown in Fig. 11.8. To the east of Svalbard there are few major structural highs or basins, although between Spitsbergen and Edgeoya lies the Storfjord Basin (see Chapter 5) and its continuation southwards into the Edgeoya Basin. Between Spitsbergen and Bjornoya is the Stappen High, and to the east the Sorkapp Basin and Hopen High. To the west lies the Vestbakken Volcanic Province, which extends as far as the continental margin. The margin itself consists of the Hornsund Fault Zone, to the west of which lies a thick sediment prism extending out to the spreading centre of the Knipovich Ridge. Tertiary erosion of the Barents Shelf left few Tertiary rocks except at the continental margin and in the deeper basins to the east. In this chapter, the continental margin, Vestbakken Volcanic Province, Stappen High and Sorkapp Basin will be described.

11.8.1

Continental margin: Knipovich Ridge to the Hornsund Fault Zone

The ocean-continent boundary west of Spitsbergen is generally considered to be the Hornsund Fault Zone, with uplifted rocks of

SOUTHERN SVALBARD: BJORNOYA AND SUBMARINE GEOLOGY 15

25

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the Svalbard platform to the east and oceanic rocks to the west. Faleide et al. (1991) presented deep seismic data across the zone which appears to confirm that this is the case, although the exact nature of the transition is uncertain as it is masked by volcanic rocks in places. The down-to-the-west step in basement topography across the faulted passive margin is infilled by a thick sequence of syn- and post-rift Tertiary sediments; the only submarine Tertiary sedimentary rocks in the NW Barents Shelf. The sequences reach a total thickness in excess of 7 k m (Myhre, Eldholm & Sundvor 1982). They are described in Section 21.4.3.

223

Seismic data presented by Myrhe, Eldholm & Sundvor (1982) showed that the fault zone varies along strike from a single fault with a step of 4 s (TWT) to a series of stepped faults. They also found that there must be at least three separate segments along the length of the zone - the southern segment from 74 ~ to 74.7~ a central section from 75 ~ to 76.4~ and a northern fault north of 76.5~ There is therefore no overlap between each segment; the northern and southern parts are approximately aligned but the central section is displaced by 40-50 km to the east. Despite accurate imaging on seismic sections, very little is known about the sediments and rocks on and to the west of the continental margin. In the southwestern part of the Barents Shelf, where more seismic data are available, depositional patterns have been well-studied, although age constraints are still very poor. The sediment wedge due west of Svalbard was first examined by Schlfiter & Hinz (1978), who described sections from the shelf edge out across the Knipovich Ridge. They identified three seismic sequences, denoted SPI-I, SPI-II and SPI-III, separated by unconformities U1 and U2. The thickness of the sequences is described in terms of reflection two-way travel time. The uppermost unit, SPI-I, thins westwards from 0.5 s off Bellsund and Isfjorden and off Prins Karls Forland, up to 1.gs. Thinning is due partially to downlapping and erosion. Internal reflectors are subparallel to divergent. Comparison with the nearby DSDP Site 344 suggested to Schliiter & Hinz that the unit consists of turbiditic terrigenous sands, sandy muds and clays, of Pliocene to Pleistocene age. The basal unconformity surface U 1 dips westwards and is hummocky, probably due to the nature of SPI-II. Reflectors in the latter are chaotic and discontinuous, suggesting that the unit may be slumped. Overall it thickens seaward from 0.1 s at the outer shelf to 0.5 s beneath the lower slope, then terminates against basement uplifts of the Knipovich Ridge. Schliiter & Hinz thought the unit to be a result of uplift of the western Barents Shelf and gave it a Pliocene age. The underlying SPI-III contains subparallel, continuous reflectors, although they are disrupted in places by faulting. The unit thins westwards and terminates against the basement highs of the Knipovich Ridge. Reflectors in the upper part are cut by the unconformity surface U2, indicating the latter was erosional. It was interpreted as being of (mid?) Oligocene age on the basis that unconformities of that age have been recognized elsewhere in the area; SPI-III was considered to be broadly Paleogene and to consist of sandstones and shales. Reappraisal of data all along the margin by Myhre & Eldholm (1988) led to different ideas on the age of the sequences. They proposed that SPI-I is of Pliocene age, SPI-II is late Miocene to Pliocene, and SPI-III is Oligocene to Miocene, although it may extend back to the Eocene south of 75~ They placed the age of unconformity U2 at 5.5 Ma, indicating that SPI-I and SPI-II were accumulated very rapidly.

11.8.2

Vestbakken Volcanic Province

The volcanic rocks within the Tertiary successions to the west of Bjornoya were investigated and reviewed by Faleide, Myrhe & Eldholm (1988). They recognized a small amplitude positive gravity anomaly over the Stappen High (near Bjornoya) and high amplitude reflectors on seismic sections in the area, which they interpreted to represent early Eocene volcanic flows. To the west the seismic markers are cut and displaced by extensional faults associated with Atlantic basin opening and passive margin formation, and hence the volcanics were interpreted as having formed during the pre/syn-rift phase in late Paleocene or Eocene times. This is confirmed by the presence of late Paleocene/Eocene tufts in the Hammerfest Basin to the south (Westre 1984) and Paleocene ash layers in the Firkanten Formation of Spitsbergen (Major & Nagy 1972). Also visible on seismic sections are volcanic peaks penetrating the older Tertiary units. They have relief of over 1 km, buried within Neogene sediments. They are probably of Otjgocene age, thought by Faleide et al. to be associated with the major change in relative plate motions at that time.

224

11.8.3

CHAPTER 11

Stappen High

The evolution of the Stappen High has been examined by Wood, Edrich & Hutchison (1989). Vitrinite reflectance data from Bjornoya (Bjoroy, Mork & Vigran 1983) and elsewhere on the western Barents Shelf indicates erosion of a considerable amount of sediment from the region: 3.5km in Bjornoya and up to 1.2kin further east at longitude 23~ This uplift has generally been associated with rift-margin thermal effects. Wood et al. (1989) constructed thermal models for the time at which the uplift is inferred to have occurred, and for the amount of uplift just stated. Their best-fit model indicates 50% lithospheric thinning at the time of rifting, with the effects of the thermal anomaly extending up to 400 km east across the shelf. They said that unpublished heat flow data supported this model, with anomalously high heat flows around the Stappen High. However, in a nearby exploration well, the maximum temperatures recorded indicate that they were set at maximum burial, suggesting that the effects of uplift and erosion had a greater compensatory cooling effect at those levels than the thermal pulse.

11.8.4

Sarkapp Basin

The basin is infilled by up to 3 km of Permian to Triassic strata, overlying older Paleozoic basement (Johansen et al. 1992). Otherwise little is known of the basin, and it is only possible to speculate on the nature of the rocks, by assuming they are similar to the onshore Permian and Triassic rocks of Svalbard. For descriptions of those rocks, see the relevant chapters of this book.

11.8.5

Crustal structure and a possible Iapetus suture

In their deep seismic study of the western margin of the Barents Shelf, Faleide et al. (1991) constructed four E-W transects down to 40km: A at 72~ (Fig. 11.8) shows the structure north of Norway; B and C generalize the structure south and north of Bjornoya; and D at about latitude 78~ running into Isjforden.

The sections plot the Moho and so include the whole crust. In each case the oceanic crust reaches 10 to 15 km of which the lower half is crystalline ocean basement and the upper projected as Cenozoic deposits. On the other hand the continental crust profiles suggests significant differences. South of Bjornoya both sections show the lower boundary of the continental crystalline (Caledonian basement) crust ranging between about 20 and 30 km. The basement thins beneath Mesozoic (mainly Cretaceous) basins down to 15 km depicted as stretching with listric faulting. These basins include the Tromso Basin (in transect A) and the Bjornoya Basin (in transect B). The volcanic province at the continental margin west of Bjornoya extends north and south in a narrow pull-apart strip having subsided about 2 km. North of Bjornoya the crystalline (basement) crust is shown in both transects C and D to be bounded more uniformly at 30 to 35 km. Section C between Bjornoya and Spitsbergen shows only about 5 km of Late Paleozoic and Early Mesozoic strata thickening eastward to 8 km on the Svalbard platform and with N-S lineaments: the Knolegga and Hornsund fault zones respectively 20 and 60 km west of Bjornoya. The Knolegga (or Bjornoya-Sorkapp) Fault Zone defines the western boundary of the Svalbard Platform, and indeed of the continental crust. Section D shows crustal thickening beneath the west Spitsbergen thin-skinned thrust structures down 5km to basement and Late Paleozoic-early Mesozoic strata thickening to 10km W of the Billefjorden Fault Zone and only about 2 km to the east. Both transects C and D reveal dominant N S linear (magnetic) features. It is suggested here that the contrast between north and south crustal characteristics at about the latitude of Bjornoya could suggest/reflect the Iapetus suture that separates Laurentia from Eurasian lithosphere possibly just south of Bjornoya. To the north the evident N-S line structures belong to the East Greenland Caledonian development. To the south the north easterly structures of Finnmark may predominate. This Caledonian collage has been truncated by the Cenozoic dextral shear zone that bounds the Barents Shelf.

PART 3 Historical Synthesis Chapter Chapter Chapter Chapter Chapter Chapter

12 13 14 15 16 17

P r e - V e n d i a n h i s t o r y , 227 V e n d i a n h i s t o r y , 244 C a m b r i a n - O r d o v i c i a n h i s t o r y , 257 S i l u r i a n h i s t o r y , 272 D e v o n i a n h i s t o r y , 289 C a r b o n i f e r o u s - P e r m i a n h i s t o r y , 310

Chapter Chapter Chapter Chapter

18 19 20 21

C h a p t e r 22

T r i a s s i c h i s t o r y , 340 J u r a s s i c - C r e t a c e o u s h i s t o r y , 363 P a l e o g e n e h i s t o r y , 388 Neogene-Quaternary h i s t o r y , 418 M o d e r n glaciers a n d c l i m a t e c h a n g e , 436

Camp on Nordenski61dkysten with mainly Carboniferous mountains in the distance which are resting unconformably on Vendian basement occupying the low ground, the whole being deformed in the Paleogene Spitsbergian Orogeny. The photograph shows a scene near the coast in Svalbard where a former plain of marine denudation is now a typical wide strandflat against the mountain cliffs. Photo P. W. Webb, 1990.

A camp on the coastal raised beaches north of Liefdefjorden. The lower ground extends to the foot of the mountain Siktefjellet (?Silurian). Since the polar bear has been protected it is fearless, inquisitive and liable to ransack any food store. In this camp the cooking tent with rations is in the background separated from the four sleeping tents. The two areas re surrounded by a trip-wire which detonates a small charge when disturbed (mainly by humans). Photo W. B. Harland, CSE 1990.

Motorboat transport was used extensively from 1965 to 1989. Each of three boats accommodates a crew of four, typically two geologists, a captain and an engineer and is dedicated to a particular research project. The boats, in radio contact, give mutual support. Living aboard avoids setting up camp and attendant concern over bears. It enables movements between anchorages when eating and sleeping in watches. This shows the aluminium boat Arctoceras with the standard inflatable dingy aoard for emergency, and the tender which is towed and then used for landing and shore journeys. Photo N. i. Cox, CSE 1983.

Ice-flows, if not densely packed, are negotiable, but subject to wind. Here the motorboat Salterella is being helped along in Hornsund. Photo N. I. Cox, CSE 1988.

Chapter 12 Pre-Vendian history W. B R I A N 12.1 12.2 12.2.1 12.2.2 12.2.3 12.2.4 12.3 12.3.1 12.3.2 12.3.3 12.3.4 12.3.5 12.3.6 12.4 12.4.1

HARLAND

with a contribution by NICHOLAS

Precambrian time scale, 229 Pre-Vendian successions, 229 Eastern terranes, 229 Central terranes, 230 Western terranes, 230 Bjornoya, 231 Pre-Vendian biotas (N.J.B.), 231 Occurrences, 232 Taxonomy, 232 Microbial mats and prokaryotes, 233 Unicellular protists (acritarchs), 234 Multicellular protists (seaweeds) and problematica, 234 Conclusion, 235 Precambrian isotopic ages, 235 Eastern terranes, 235

It so happens that rocks of Vendian age are extensive and are well exposed in Svalbard. This applies especially to early Vendian, i.e. Varanger, with two distinctive glacial horizons as are treated in the Chapter 13. The Early Varanger (Sm~dfjord) episode can be correlated in most sections and so provides a reference horizon which serves approximately to identify pre-Varanger rocks. The preVendian rocks have yet to show such good correlation characters. Therefore in Svalbard it is convenient to consider pre-Vendian successions together. Their distribution is shown in the map (Fig. 12.1). Some pre-Vendian sequences are punctuated by unconformities. Moreover, the sequences contain both high-grade metamorphosed and highly deformed rocks as well as undeformed fossiliferous strata. Therefore it is of interest to determine any Precambrian diastrophism and even tectonothermal events. The term proto-basement was introduced (Harland 1997) to distinguish a Precambrian basement, that formed in (say) Proterozoic time, from the ubiquitous basement formed by Early to mid Paleozoic tectogenesis, but made largely of Precambrian rocks. It is to distinguish proto-basement within the basement underlying Devonian and Carboniferous strata. Protobasement from such a study (structural, stratigraphic, isotopic) is shown in darker ornament in Fig. 12.1 and discussed in Section 12.3. Were the spatial relationships between these localities originally as now, intense tectonism, metamorphism and magmatism would suggest a division of Precambrian history in Svalbard by such events. But Svalbard, small though it is on a global scale, comprises three or more distinct provinces which in Precambrian and early Paleozoic times may have been far distant. Therefore a simple compilation and correlation between the several terranes may make little sense. The boundaries posited here between the three principal terranes are shown in both Figs 12.1 & 12.6. Even the possibility, of a three or four province-terrane hypothesis must limit the value of simple lithological correlation throughout Svalbard. Therefore each terrane is treated in the next section on its own merits. Such treatment does not require acceptance of three distant provinces. It does, however, focus investigation on the independent evidence in each terrane for age estimates. The obvious isotopic path to such thinking is obscured by the ubiquitous Early to Mid-Paleozoic tectono-thermal events. The biostratigraphic route is similarly compromised. Therefore successions from the preceding chapters are summarized and combined, terrane by terrane, before overall discussion of correlation by the meagre biostratigraphic and isotopic data. Those who do not accept these terranes as originally distant have a greater problem in correlating between them. At the same time readers should be reminded that were the Vendian conclusions of Harland, Hambrey & Waddams (1993) shown to be flawed then many rocks taken in this work as Vendian would need to be added to the list of Pre-Vendian strata. Consequently the outcrops of Fig. 12.1 would be enlarged and those of Fig. 13.1 correspondingly reduced.

12.4.2 12.4.3 12.4.4 12.5 12.5.1 12.5.2 12.5.3 12.6 12.6.1 12.6.2 12.7 12.7.1 12.7.2 12.7.3

J. B U T T E R F I E L D

Central terranes, 236 Western terranes, 236 Sequence of Precambrian isotopic ages, 236 Tectonostratigraphic evidence for proto-basement, 236 Eastern terranes (Province), 237 Central terranes, 238 Western terranes (Province), 239 Pre-Vendian correlation, 239 Correlation within Svalbard, 239 Pre-Vendian correlation beyond Svalbard, 240 Palinspastic considerations, 240 Global configurations, 240 Svalbard relationships, 241 An East Greenland aulacogen, 242

Whereas prospects of Precambrian hydrocarbons are commonly ignored some authors have made a case. Danyushevskaya et al. (1970) considered the geochemistry of dispersed organic matter especially within the carbonate facies of the Neoproterozoic Hecla Hoek succession in Nordaustlandet. In the eastern terranes later Neoproterozoic environments generated slow deposition in shelf and lagoonal carbonates. The original bitumen-like material is generally closely related to biogenic sedimentary structures. Birkenmajer, Frankiewicz & Wagner (1992) reported on late Proterozoic anthracite coals from the Hornsund area. These were irregular voids in the H6ferpynten (dolostone) Formation (Andvika Mbr) in Hornsund and at Krakken (in middle west Wedel Jarlsberg Land) filled by bitumen and subsequently coalified in the (?Caledonian) orogeny. Temperatures of over 500~ and pressure of over 20,000 M P a were estimated. All these dolomitic strata could be coeval (at 7750Ma) and certainly were extensive. The two occurrences which have been investigated in detail have similar characteristics. Place and stratal names used for major units in Fig. 12.1 Outcrop Area Russehamna Formation 1. Bjornoya 2. Sorkapp Land Mefonntoppane and Kistefjellet rocks H6ferpynten Formation Sigfredbogen unit 3. Wedel Jarlsberg Land: south western Eimfjellet Group Isbjornhamna Group western Nordbukta Group northern Magnethogda Group 4. Nathorst Land Magnethogda Group 5. Nordenski61d Land Nordenski61dkysten outcrop 6. Oscar II Land: central Vestg6tabreen Complex central west Miillerneset Formation northern Kongsvegen Group Pinkie Formation 7. Prins Karls Forland 8. Albert I Land Krossfjorden Group Biskayerfonna and Lerneroyane groups 9. Haakon VII Land Richarddalen Complex 10. Ny Friesland Stubendorffbreen Supergroup (Western Schists and Gneisses) AtomfjeHa Complex Finnlandveggen Group Eskolabreen Formation 11. Nordaustlandet Brennevinsfjorden Group (and islands to north) Duvefjorden Complex (palaeosomes in migmatites) 12. Storoya and Kvitoya

228

CHAPTER 12

Fig. 12.1. Outcrops of pre-Vendian rocks (mainly Proterozoic). The bold dashed lines mark the general boundaries of the major terranes.

PRE-VENDIAN HISTORY

12.1

Precambrian time scale

For convenience a summary of the Precambrian time scale is tabulated in Fig. 12.2. It is in two disconnected parts. On the right is the internationally agreed chronometric scale. That means that the boundaries have been agreed precisely in years that so define the meanings of the names. On the left is a chronostatic scale not yet agreed internationally because each name would have to be internationally agreed and its boundaries defined at GSSP (golden spikes) in rock successions, a process that will take many years. However, this procedure is well established, has been applied to most Phanerozoic divisions down to the initial Cambrian boundary, is being applied by an international working group on the next earlier (or latest Pre-Cambrian) period, and will be applied successively as earlier stratigraphy is sorted out. The chronometric scale is easy to apply to numerical age data and the chronostratic to the correlation characters in rock sequences such as biostratigraphic, climatic, magnetic, volcanic. Until recently now Precambrian classification was limited to chronometric definition but both scales may apply to all rocks with advantages and disadvantages in particular cases. The chronostratic scale listed in the left hand part of the figure is taken from Harland et al. (1990). The chronometric scale is from the IUGS Subcommission on Precambrian stratigraphy in 1988 (Harland et al. 1990, p. 17) who made it clear that, whereas the names derived from aspects of Earth history, they were not so defined. Thus, even if the names prove to be inappropriate they stand.

12.2

Pre-Vendian successions

In this resum~ of pre-Vendian rocks described in the foregoing chapters, rock units are summarized and they are classified in each

CHRONOSTRATIC AGE

229

of three groups of terranes. This does not necessarily imply that these terranes were once far distant provinces; but it is as convenient as any other arrangement for discussion without prejudice, and more meaningful if the four-terrane hypothesis has substance. The major terranes each may be divided on other evidence into subterranes which are not considered as palinspastically significant on a global scale.

12.2.1

Eastern terranes (Fig. 12.3)

The Nordaustlandet and Ny Friesland successions (Chapters 6 and 7 respectively) are similar to each other and differ from others in Svalbard. An approximate correlation is indicated in Fig. 12.3. The successions are, however, remarkably similar to those in Central East Greenland. In each case they lie conformably, or at least concordantly, beneath the older of the two Varanger tillite horizons. These terrane are bounded in Svalbard on the west by the Billefjorden Fault Zone. To the east of the BFZ a major boundary has not been recognised. However, the Veteranen line (Harland et al. 1992) separates two subterranes in N y Friesland. There may well be further subterranes to the east. The eastern terranes are truncated on their western boundary by the Billefjorden Fault Zone. Some of the depocentres appear near the middle of Ny Friesland. The Lomfjorden and Murchison Bay supergroups are of similar thickness and facies and (as with the Hinlopenstretet Supergroup) they straddle Hinlopenstretet without significant difference. However, the earlier history may differ in that Ny Friesland had a significant c.1750 M a magmatic event and Nordaustlandet at c.950 M a and as discussed in chapters 6 and 7.

B o u n d a r y to be defined in strata (GSSP)

CHRONOMETRIC SCALE .E_ .E--

PHANEROZOIC

Early Cambrian

Nemakit-Daldyn

i

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Poundian

Ediacara

Varanger

Wonokan Mortensnes Sm&lfjord

590 610-

< O UJ

n,' s

O O N O n,'

- 650 -

Cryogenian - 850 -

LU

tO n,'

Karatau Q_

1050

Mesoproterozoic

Yurmatin -1350

Burzian

1650

Animikean

Paleoproterozoic

2200

Huronian

Tonian

13_

-2450

Randian

Stenian Ectosian Calyminian Stathenian Orosinian Rhyreain Siderian

-1000 -1200 -1400 -1600 1800 2050 2300 2500

Neoarchean 2800

2800

Z

<

Swazian

Mesoarchean 3200

UJ

3310

Fig. 12.2. Precambrian timescale comparing chronostratic and chronometric scales, based on Harland et al. (1990) with the initial Phanerozoic boundary calibrated according to Bowring et al. (1993).

Neoproterozoic

i

800 -

z < n*

Neoproterozoic III

580 -

Sturtian

rn

545 -

545

Isuan 3800

-1O n,' <

Paleoarchean 3600

Eoarchean 4000

Hadean Priscoan -456o

230

CHAPTER 12

NY FRIESLAND

NORDAUSTLANDET

HINLOPENSTRETET SUPERGROUP

-s

OSLOBREEN GROUP

V

POLARISBREEN GROUP Dracoisen Fm. Wilsonbreen Frn. Elbobreen Fro. LOMFJORDEN SUPERGROUP AKADEMIKERBREEN GROUP 1250 m Backlundtoppen Formation

GOTIA GROUP KlackbergbuktaFormation Sveanor Formation Baklaberget Formation MURCHISON BAY SUPERGROUP ROALDTOPPEN GROUP 1250 m

CELSIUSBERGET GROUP 2140 m VETERANEN GROUP 3800 m

FRANKLINSUNDET GROUP 3175 m

3TUBENDORFFBREEN SUPERGROU[ 950 Ma

PLANETFJELLAGROUP 4700 m

"1317 Ma

HARKERBREENGROUP 4000m

"1190 Ma

FINNLANDVEGGENGROUP 2700m

,.,.vvv-,.,,v.~ ? LAPONIAHALVOYAGRANITES " / 7 KAPP HANSTEEN GROUP /

ATOMFJE,,A OOMP'EX

/ % Q % ~ ,%to 9_OXSq/ ~-~,~-~.~-~

.z,~O" ~ ' ~ " ~ / _ ~

Fig. 12.3. Correlation of pre-Vendian sequences of Ny Friesland and Nordaustlandet. *Detrital zircons give maximum stratal ages.

12.2.2

Montblanc Fm, 0.5-1.0km, pelites, quartzites, amphibolites, and gneisses.pass down into migmatites Rieharddalen Complex Eclogite, mylonitic metagranites, metabasic and ultrabasic rocks, gneisses and marbles.

Central terranes

There are at least three subterranes: a N o r t h Central Terrane ( = Andr6e L a n d Terrane) is of D e v o n i a n strata; the n o r t h w e s t e r n T e r r a n e is divisible into two subterranes: the western northwest terrane and the B i s k a y e r f o n n a - H o l t e d a h l f o n n a terrane. These cover the whole of northwest Spitsbergen as far south as K o n g s f j o r d e n , including the islands in the fjord (Lov6noyane). A fourth P r e c a m b r i a n subterrane is south o f the Central Basin and seen in South Spitsbergen east of H a n s b r e e n , there is no direct correlation between these terranes, the n o r t h w e s t e r n being older than the southern so the succession will be presented in two parts. They are considered as one main terrane by virtue of their characters which contrast with those to east and west, so from a P r e - V e n d i a n point o f view there is n o t h i n g inherent in these rocks to g r o u p together the n o r t h and south subprovinces. The southern subprovince depends on Vendian and Early Paleozoic characteristics which have no equivalents in the north. However, they are united by similar D e v o n i a n strata.

(a) Northwestern Spitsbergen (i) The Western Northwestern Subterrane may be labelled Albert I Land with the Precambrian Krossfjorden Group, described in Chapter 8 and listed below. Krossfjorden Gp, 6-8 km Generalfjella Fm, 2-2.5 km, marbles and pelites Signehamna Fm, 2-2.5 km, mainly pelites Nissenfjella Fro, 2-3 kin, pelites and amphibolites passing down into migmatites, possibly up to 5 or 6km as estimated by Ohta (1969). (ii) The Biskayerfonna-Holtedahlfonna Sub-terrane. This may also be labelled the Haakon VII Land subterrane. The upper two groups of Gee (in Harland 1985) correspond with the Krossfjorden Group above which is thus extended to include the formations in this subterrane. The Richarddalen Complex may be the oldest in northwestern Spitsbergen. Krossfjorden Gp, 1.2-1.5 km Lerneroyane (marble) Fm Pteraspistoppen (marble) Mbr Erikbreen (pelite) Mbr Horneba~kpollen (marble) Mbr Biskayerfonna Subgp Biskayerhuken (pelite) Fro, 3.5+ km

(b) Southern Spitsbergen. The m a i n outcrops are P h a n e r o z o i c a n d V e n d i a n and the Pre-Vendian o u t c r o p s are somewhat isolated in four areas (i) to (iv). (i) Northern Wedel Jarlsberg Land, east of Recherchefjorden and also the western tip of Nathorst Land. Magnethogda Gp This group or sequence has not yet been defined by its constituent formations which have been so far treated as map units (e.g. Dallmann et al. B l l G , 1990). The following units may in due course be described as formations: banded limestone and white marble; dark phyllite; yellow dolostone; grey green quartzite; feldspathic quartzite and augen gneiss; grey dolostone with hematite; layered quartzite. (ii) South of Hornsund and east of the Hansbreen fault line G~tshamna Fm (?Vendian) Faulted contact H6ferpynten Fm, with six members, dominantly of dolostones. (iii) Northeast of Hornsund Hyrneodden Fm. Probably faulted contact with Devonian strata to east and of uncertain age: Cambrian or Precambrian (iv) Central Sarkapp Land Mefontoppane rocks in north and Kistefjellet rocks in south.

12.2.3

Western terranes (Fig. 12.4)

The unity of this province and contrast with those to the east is seen in the Vendian and Early Paleozoic successions. The P r e - V e n d i a n strata are scattered, a n d not necessarily coeval (Fig. 12.4). They are listed below from n o r t h to south.

(a) Outcrops between Kongsfjorden and Isfjorden (i) Prins Karls Forland Ferrier Gp. Four formations (Late Varanger). Faulted contact ?St Jonsfjorden Gp (Vendian) Pinkie Fm (?Varanger/pre-Varanger) (ii) Oscar II Land: north of St Jonsfjorden (Chapter 9) St Jonsfjorden Gp. Four formations the lowest being the Kongsvegen Gp (Vendian) Bogegg Fro, 1500m. three members, mainly pelitic, but some semipelites, feldspathites and amphibolites Steenfjellet Fm, 270 m Dolomitic marble, a distinct light coloured marker band between dark pelite and psammite formations. Nielsenfjellet Formation, 2540 + m Psammites, pelites and some feldspathites. (iii) Oscar II Land: south of St Jonsfjorden St Jonsfjorden Gp (Vendian) Trondheimfjella Fm is the lowest of four formations in the group. Whereas just south of St Jonsfjorden, the Trondheimfjella Fm is missing so that a presumed tectonic contact with the older rocks is evident by a marked contrast in metamorphic facies, further south there may be a stratigraphic transition, just north of Eidembukta where a concordant relationship is evident. Indeed it is not obvious where the boundary should be drawn between the Trondheimfjella Fm and the underlying Mtillerneset Fm. Kongsvegen Gp (?pre-Vendian) Mfillerneset Fm, 2 + km. Mainly of pelites and semipelites contrast with the formation above by lack of calcareous strata and psephites.

PRE-VENDIAN HISTORY Prins Karls Forland

Fig 12.4. Correlation of pre-Vendian sequences of the western terranes. The three units marked with a dagger (t), and with tectonic contacts, have higher grade metamorphic facies than the surrounding rocks and have been assigned here as separate occurrences of Ordovician metamorphism, probably, of Early Varanger (Vendian) basic volcanic rocks, and so are not pre-Vendian. Only the lowest Vendian units are shown: open triangles, lower tillite; black triangle, upper tillite.

Lower Vendian

Oscar II Land North

231 Oscar II Land South

Trondheimflella Formation

Ferrier Group

Units

? .....

Kongsvegen Group /

? Pinkie unit'l"

/

/

/

.... .....

Kaffioyra Complexl ! Vestg6tabreen Cpx.1"

Pre-

(b) Outcrops between Isfjorden and Bellsund (Chapter 10). Within western Nordenski61d L a n d (i.e. Nordenski61dkysten) all outcropping formations would be Varanger (Early Vendian) in age according to Harland, H a m b r e y & W a d d a m s (1993). The Late Varanger tillite horizons are at the top (in the north) and the Early Varanger tillite horizons at the b o t t o m (in the south) with other formations of intermediate age between. Alternative view points postulates only one tillite horizon and so m u c h of the outcrop would be of pre ?Varanger age.

(c) Northwestern Wedel Jarlsberg Land (Chapter 10). The succession as recorded by several workers was summarized by Harland, H a m b r e y & W a d d a m s (1993) on which this s u m m a r y account depends.

Conglomeraffjenet Gp, with many Vendian formations (Early Varanger). Floykalven Fm, with conspicuous deformed carbonate stones tillite horizon Thiisfjellet Fm (?Early Vendian), black pyritic limestone and base conglomerate; is conformable above and unconformable below; is of variable thickness. Nordbukta Gp, c3300m. This group comprises eight formations mainly of carbonates and phyllites with quartzite formations at the base. The following list of formations is taken from Bjornerud (1990) and map B l l G (Dallmann et al. 1990). (8) Dordalen Fm, 150+ m heterogeneous dolostone and phyllite (7) Thiisdalen Fm, 200 m red-brown phyllite and quartzite (6) Trinutane Fro, 380 m (iii) Ferroan dolostone and pink marble, 150 m (ii) Resinous phyllite, 30m (i) Pink cross-bedded quartzite, 200 m (5) Saljehaugfjellet Fro, 200 m (ii) Grey dolostone, 150 m (i) Black limestone, 50m (4) Botnedalen Fm, 300m platy limestone, dolostone and phyllite

Floykalven Formation

Elveflya Formation

MOllerneset Fm.

.... T-TITT

J~, , , . . i,,,

Nordbukta sequence

Vendian

Vestg6tabreen Complex. A structurally complex association of blue schist facies. Overlain unconformably by mid-Ordovician strata and with isotopic ages suggestive of Llanvirn-Caradoc metamorphism yet with a possible zircon age determination of 2121 Ma. In this respect the thinking here is that such compositions could derive from the basic rocks in the St Jonsjforden Gp and so be originally Vendian with Ordovician tectonism. This author, from sundry visits, concluded that the scattered exposures on Sarsoyra represented a strike-slip m61ange. Ohta et al. (1995) not only came to the same conclusion but identified the peculiar green-brown dolomitic rocks as low temperature-high pressure metamorphics rich in MgO and Cr203 analogous to some Vestg6tabreen rocks. It is a significant advance to relate this belt of (Paleogene) dextrally sheared rocks through Kattioyra and Sarsoyra to the Vestg6tabreen Complex. Ohta et al. agree in relating these rocks within the St Jonsfjorden Group but they regarded that group as Middle Proterozoic whereas it has been argued to be Vendian on the basis of the lower tillite at its base by Harland, Hambrey & Waddams (1993).

WEDEL JAI~LSBERG LAND North [ South

? Dunoyane

Eimq]olletGroup Isbjomhamna Group

(3) Peder Kokkfjellet Fm, 60 m sandy dolostone (2) Evafjellet Fm, 1000? m quartzite and phyllite (1) Kapp Berg Fm, 1000?m phyllite and quartzite.

(d) Southwestern Wedel Jarlsberg Land: south of Torellbreen WerenskiiildGp Deilegga Fm Jens Erikfjellet (volcanic) Fm Elveflya (tillite) Fm (=Vimsodden tillite), with Slyngfjellet Conglomerates (Early Varanger) Unconformity and Vimsodden-Kosibapasset Fault (VKF). Eimfjellet Gp (sensu Czerny et al. 1992). Pyttholmen Fm Gullichsenfjellet Fm Bratteggadalen Fm Skfilfjellet Fm Eimfjellbreane Fm Skjenstranda Fm

IsbjornhamnaGp Revdalen Fm Ariekammen Fm Skoddefjellet Fm The above summary succession for southwestern Wedel Jarlsberg Land is the solution in this work to the conflicting schemes of Birkenmajer (1993), Harland et al. (1993), Czerny et al. (1992) and Balashov et al. (1995) and is argued in more detail in Section 10.7.1. The contention here is that the rocks at least down to the Vimsodden tillite (Elveflya Formation) with the Slyngfjellet Conglomerate are Early Varanger, rather than pre-Vendian. The Eimfjellet and Isbjornhamna groups are certainly proto-basement and appear to be conformable or at least concordant. Alternative viewpoints have been consistently expressed by Birkenmajer from 1957 to 1993, and Balashov et al. as well as Czerny et al. have followed Birkenmajer in regarding the Deilegga rocks as pre-Vendian (see Section 10.7.1)

(e) Sorkapp Land (Chapter 10) Sigfredbogen Formation This unit consists of psephites and psammites. It is not easily related or correlated.

12.2.4

Bjornoya (Chapter 11)

S o r h a m n a F o r m a t i o n (?Late V a r a n g e r - E a r l y Vendian) R u s s e h a m n a F o r m a t i o n , 500 m, is the Older D o l o m i t e Series of Holtedahl. It comprises five divisions of which the upper three are probably Vendian and the lower two m a y be pre-Vendian.

12,3

Pre-Vendian biotas

Until the publication in 1995 o f B a r g h o o r n & Tyler's seminal paper on the microfossils of the early Proterozoic Gunflint Chert, the existence of Precambrian fossils, h a d remained a matter of contention. Since then the field has b u r g e o n e d to become a discipline

232

CHAPTER 12

in its own right with an increasingly detailed record, especially Neoproterozoic, offering stratigraphic and palaeobiological information on a level approaching the Paleozoic record (e.g. Knoll & Butterfield 1989; Schopf & Klein 1992; Bengtson 1994). The preVendian Neoproterozoic (PVN) sedimentary sequences of NE Svalbard have contributed importantly to this recent progress with an exceptional fossil record providing an unprecedented view into the diversity, ecology and evolutionary status of Neoproterozoic life. The most obvious manifestation of Precambrian life is not so much in its fossils per se as in the record of microbially-induced sedimentary structures e.g., stromatolites, oncolites and microphytolites. These 'microbialites' are commonly preserved in the PVN carbonate sequences of Svalbard, and elsewhere, and provide the basis for a broad biostratigraphic zonation/correlation, as well as palaeo-environmental information (Raaben 1960, 1967; Mil'shteyn 1967, 1975; Golovanov 1967, 1976; Golovanov & Raaben 1967; Raaben & Zabrodin 1969, 1972; Mil'shteyn & Golovanov 1976, 1979, 1983; Knoll 1984; Swett & Knoll 1985; Knoll et al. 1989). Indeed, prior to the introduction of a relatively reliable Neoproterozoic acritarch biostratigraphy, and C and Sr chemostratigraphy, they offered the best available, and still valid, age estimate for these successions, i.e. Late Riphean.

12.3.1

Svanbergfjellet Fro: ST, MM, LA, AA, SW, PR (Butterfield, Knoll & Swett 1988, 1994) Grusdievbreen Fm: nil Veteranen Gp (Knoll & Swett 1985) Oxfordbreen Fro: MM, LA (Knoll & Swett 1985) Glasgowbreen Fm: MM, LA (Knoll & Swett 1985) Kingbreen Fm: MM, LA (Knoll & Swett 1985) Kortbreen Fm: MM, LA (Knoll & Swett 1985) Nordaustlandet and L~gaya:

Murchisonfjorden Supergp Roaldtoppen Gp Ryss6 Fro: ST, MM, LA, VS, AA (Knoll & Calder 1983) Hunnberg Fm: ST, MM, LA, AA (Knoll 1984) Celsiusberget Gp (Knoll 1982b) Raudstup Fm: nil Slodd Fm: nil Norvick Fm: LA (Knoll 1982b) Flora Fro: MM, LA (Knoll 1982b) Franklinsundet Gp (Knoll 1982b) Kapp Lord Fm: MM, LA, PR (Knoll 1982b) Westmanbukta Fm: LA (Knoll 1982b) Persberget Fm: nil

Occurrences 12.3.2

Due to their lack of mineralized hard parts, individual organisms of pre-Vendian age are much less readily preserved than their sedimentary traces. In northeast, however, particularly fortuitous combinations of deposition, early diagenesis and geological history have conspired to preserve such fossils in 14 of the 17 formations that comprise the Lomfjorden (Ny Friesland) and Murchison Bay (Nordaustlandet) supergroups. As with other Proterozoic occurrences, these fossils typically occur in one of two preservational modes which represent distinct palaeoenvironements and taphonomic pathways: (1) organic-walled compression fossils/microfossils in fine-grained siliciclastic rocks or (2) three dimensional, silica-permineralized microfossils in clear-water (and/ or supratidal) carbonate facies. The Svalbard succession is notable in that, for both of these taphonomic modes/palaeoenvironments, it hosts some of the most diverse and best preserved Neoproterozoic fossil assemblages yet reported. Exceptionally preserved chert biotas occur in the Svanbergfjellet (Butterfield, Knoll & Swett 1994), Draken Conglomerate (Knoll 1982; Knoll, Swett & Mark 1991) and Backlundtoppen (Knoll et al. 1989) formations of Ny Friesland and the correlative Hunnberg (Knoll 1984) and Ryss6 (Knoll & Calder 1983) formations of Nordaustlandet. Shale-hosted fossils are reported from most of the formations here, but truly exceptional preservation appears limited to the Svanbergfjellet Formation (Butterfield, Knoll & Swett 1988, 1994). Stratigraphy and palaeontology of the pre-Vendian Neoproterozoic in Ny Friesland and Nordaustlandet

Bracketed lower case letters refer to type of fossiliferous lithology (sh, shale; ch, chert; cb, carbonate; ph, phosphate). Upper case letter codes refer to types of fossil present: ST, Stromatolites and/or oncolites; MM, microbial mat biotas (prokaryotic microfossils, filamentous and spheroidal); EN, endolithic biotas (in oolites/pisolites/oncolites); LA, leiosphaerid (unornamented) acritarchs; VS, vase-shaped microfossils (Melanocyrillium); AA, acanthomorphic (ornamented) acritarchs; SW, seaweeds (multicellular algae); PR, problematic large and/or multicellular fossils. Ny Friesland

Lomfjorden Supergp Akademikerbreen Gp Backlundtoppen Fm: ST, EN, LA, VS (Knoll et al. 1989) Draken Conglomerate Fro: ST, MM, LA, VS, AA (Knoll 1982a; Knoll, Swett & Mark 1991)

Taxonomy

With its wealth of well preserved material the PVN of Svalbard has contributed significantly to the primary documentation of Proterozoic fossil diversity. Approximately 150 species/forms have been cited in the eight publications addressing fossil taxonomy to date, including 29 newly named species (n.sp.), 11 new genera (n.gen.), and 11 new combinations (n.comb.) (transfer of a species to a different genus). New fossil taxa named from the Pre-Vendian Neoproterozoic of Svalbard

Reference New taxon Knoll (1982) Salome svalbardensis Synodophycus euthemos *Sphaerophycus wilsonii Eosynechococcus brevis Eosynechococcus depressus Gloeodiniopsis mikros M yxococcoides cantabr(~iensis Myxococcoides ovata Knoll & Calder (1983) Scissilisphaera regularis Knoll (1984) Cymatiosphaeroides kullingii * Trachyhystrichosphaera vidalii Knoll et al. (1989) Eohyella elongata Knoll, Swett & Mark (1991) Coniuntiophycus majorinum Myxococcoides distola Myxococcoides chlorelloidea Siphonophycus robustum Siphonophycus septatum GorgoniaThaeridium maximum Butterfield, Knoll & Swett (1994) Palaeastrum dyptocranum Proterocladus major Proterocladus minor Proterocladus hermannae Pseuclotawuia birenifera Valkyria borealis Cerebrosphaera buickii Osculosphaera hyalina Pseudodendron anteridium Dictyotidium fullerene Germinosphaera jankauskasii

n.gen., n.sp. n.gen., n.sp. n.sp. n.sp. n.sp. n.sp. n.sp. n.sp. n.gen., n.sp. n.gen., n.sp. n.sp. n.sp. n.sp. n.sp. n.sp. n.comb. n.comb. n.comb. n.gen., n.sp. n.gen., n.sp. n.sp. n.sp. n.gen., n.sp. n.gen., n.sp. n.gen., n.sp. n.gen., n.sp. n.gen., n.sp. n.sp. n.sp.

PRE-VENDIAN HISTORY

Trachyhystrichosphaera polaris Siphonophycus thulenema Digitus adumbratus Leiosphaeridia wimanii Eoentophysalis croxfordii Cephalonyx geminatus Oscilliatoriopsis amadeus Siphonophycus typicum Siphonophycus solidum Tortunema wernadskii Germinosphaera fibrilla * now recognized as junior synonyms

n.sp. n.sp. n.sp. n.comb. n.comb. n.comb. n.comb. n.comb. n.comb. n.comb. n.comb.

This, however, is merely an enumeration of names, many of which are clearly illegitimate (e.g. junior synonyms) and/or invalidly published. Recent studies have become much more observant of the ontogenetic, ecologic and taphonomic variation possible within a fossil taxon, resulting in considerably lower, but more realistic estimates of fossil diversity (Butterfield, Knoll & Swett 1994); a major advance came with the recognition that much of the distinction between chert- and shale-hosted microfossils is taphonomic and therefore not applicable in a natural classification (Knoll 1984; Knoll, Swett & Mark 1991; Butterfield, Knoll & Swett 1994). In this light, and with a sceptical eye to the taxonomic inflation associated with smooth-walled 'leiosphaerid' acritarchs and probable pseudofossils such as Bavlinella; it is estimated that the PVN of Svalbard hosts c. 85 well-defined, legitimate fossil species.

12.3.3

Microbial mats and prokaryotes

Populations of benthic micro-organisms are richly represented in both intertidal carbonates and shallow-water shales of the PVN of Svalbard. In both facies they most commonly occur in fragments of ripped-up and redeposited microbial mats; in carbonates these are particularly conspicuous as the organic-rich mat shards are often preferentially silicified in black chert e.g. Draken (conglomerate) Formation. Like their modern cyanobacterial counterparts, these fossil mats display a considerable range of community composit i o n - f r o m monospecific populations of filaments or spheroids to more heterogenous assemblages with various forms dwelling within and/or falling into (plankton) the principal mat-builder. The differences between these various mat communities reflect a range of ecological settings, and therefore palaeoenvironmental conditions (Knoll, Swett & Mark 1991). These microbial mat fossils appear to represent only the uppermost photosynthetic layers of what must have been a much more complex community of autotrophic and heterotrophic bacteria. That the fossils were photosynthetic can be inferred from their shallow-water (and therefore photic-zone) depositional environment and an overall comparison in form and habit with modern photosynthetic microbes, including the occurrence of mat-forming filaments with an alternating horizontal/vertical (diurnal) orientation (Knoll, Swett & Burkhandt 1989, fig. 3.6; Butterfield, Knoll & Swett 1994, fig. 26I)' The case for these simple fossils being true cyanobacteria, however, is often less convincing and most of the constituents of the Svalbard mats, as with Proterozoic mats in general, can be assigned only tentatively to this group. Most species of the important mat builder Siphonophycus, for example, are certainly comparable to the simple filamentous sheaths of modern Lyngbya/Phormidium-type cyanobacteria, but could as well have derived from a flexibacterium such as Chloroflexus. Similarly, septate filaments in the Svanbergfjellet shales may represent an oscillatorian cyanobacterium or Beggiatoa-like sulphur bacteria (Butterfield, Knoll & Swett 1994, pp. 13, 59). The extreme case of such taxonomic uncertainty occurs with the ubiquitous mat dweller (and/or allochthon) Myxococcoides. These 3-35#m diameter spheroidal microfossils are neither too large to be prokaryotes nor too small to be eukaryotes and so cannot be classified with confidence at even the superkingdom/domain level. Some definitive taxonomic assignments nevertheless can be made through a recognition of distinctive patterns of cell division,

233

sheath formation or filament organization. The coiling habit of Obruchevella in the Svanbergfjellet shales, for example, clearly allies it with the living cyanobacterium Spirulina and thus places it within the Oscillatoriales; both Gloeodiniopsis and Eoenophysalis (Svanbergfjellet and Draken cherts) are assignable to the Chroococcales on the basis of cell division patterns and sheaths; while Synodophycus (Draken cherts), Scissilisphaera (Ryss6 cherts), Eohyella (Blacklundtoppen cherts) and Polybessurus (Svanbergfjellet and Draken cherts) all exhibit developmental patterns (e.g. baeocyte formation) diagnostic of the Pleurocapsales. More problematically, a filamentous fossil in the Svanbergfjellet shales, Pseudodendron, appears to have a false branching habit similar to that in modern scytonemataceans (Oscillatoriales). Overall it is clear that representatives of many/most living cyanobacterial groups can be recognized in the PVN of Svalbard. Such identification has contributed importantly to the realization that the cyanobacteria, and indeed the prokaryotes in general, were of more or less modern aspect by at least Neoproterozoic time. Despite their broad range of taxonomic uncertainty, and an evolutionary status that precludes any biostratigraphic applications, these microbial mat biotas can be valuable as high resolution measures of palaeoenvironment, a role to which the Svalbard fossils have been applied with particular success (e.g. Knoll 1984; Knoll, Swett & Mark 1991; Butterfield, Knoll & Swett 1994). Close attention to associations, orientations and overall 'behaviour' can also reveal significant palaeoecological detail, such as the endolithic habit of Eohyella (Knoll, Swett & Burkhandt 1989), the epilithic colonization of microbialite intraclasts by Sphaerophycus (Butterfield et al. 1994) and the crust-forming and vertically migrating Polybessurus (Knoll et al. 1991; Butterfield et al. 1994). Moreover, the occurrence of calcified microbes in Draken stromatolites indicates that biomineralization was not entirely absent prior to the Vendian and has prompted a hypothesis on the nature of calcification through the Precambrian/Cambrian transition (Knoll et al. 1993).

12.3.4

Unicellular protists (acritarchs)

Acritarchs are unicellular organic-walled fossils of unknown taxonomic affinity but generally assumed to be the cysts, spores or vegetative cell walls of eukaryotic algae; other protists, as well as fungi, metazoans, and possibly extinct groups might also be represented. Acritarchs are distinguished from unicellular prokaryotes on the basis of size (modern cyanobacterial cells rarely exceed 15 #m diameter), morphological complexity (essentially absent in unicellular prokaryotes), and/or mode of life (planktic unicellular prokaryotes tend to be extremely small). Unlike the situation with prokaryotes, eukaryotes in the pre-Vendian Neoproterozoic are not at all of modern aspect and appear to have been undergoing significant evolutionary change through this interval. Furthermore, many, though not all, acritarchs appear to have been planktic and are therefore relatively widespread, both palaeoenvironmentally and geographically. Thus, whatever their higher taxonomic relationships, they offer a real potential for a biostratigraphic zonation of Neoproterozoic time. Proterozoic acritarchs are best known from fine-grained siliciclastic facies, but they are also common in subtidal silicified carbonates; indeed, they can be found in all but the most restricted intertidal/supratidal settings. The vast majority of acritarchs in the PVN of Svalbard, as for Neoproterozoic assemblages in general, are relatively thin-walled, unornamented spheroids (leiosphaerids) ranging from less than 10 #m to over 1000 #m diameter. Very little can be done with the taxonomy of such forms other than to identify recurring size frequency distributions and, perhaps, distinguish different wall textures and thicknesses. A crude biostratigraphy based on such forms has been applied to the Svalbard sequences (e.g. Knoll 1982b, 1984; Knoll & Calder 1983; Knoll & Swett 1985). Unfortunately, the difficulty in identifying diagnostic characters in the various 'species,' the probability that much of the reported

234

CHAPTER 12

diversity is intraspecific/taphonomic, and the extreme longevity of leiosphaerid taxa seriously undermine the stratigraphic utility of these fossils. There has been a small renaissance in Neoproterozoic acritarch research over the past two decades with the discovery of an increasingly diverse range of morphologically complex or ornamented acritarchs. The PVN of Svalbard has played a central role in this with 13 distinct forms reported to date (including five new species, two new genera and two new combinations); these can be categorized broadly as either acanthomorphs (spine-bearing) or ornamented sphaeromorphs (including VSMs, vase-shaped microfossils).

Ornamented acritarchs reported from the pre-Vendian Neoproterozoic formations of Svalbard Acanthomorphs

Cymatiosphaeroides kullingii, Svanbergfjellet, Draken, Hunnberg Comasphaeridium sp., Svanbergfjellet Dictyotidium fullerene, Svanbergfjellet Germinosphaera bispinosa, Svanbergfjellet Germinosphaerafibrilla, Svanbergfjellet Germinosphaerajankauskasii, Svanbergfjellet Goniosphaeridium sp., Svanbergfjellet Gorgonisphaeridium maximum, Draken *Gorgonisphaeridium sp. Svanbergfjellet Trachyhystrichosphaera aimika, Svanbergfjellet Trachyhystrichosphaerapolaris, Svanbergfjellet *T. vidalii (= T. aimika), Draken, Hunnberg, Ryss6 Ornamented sphaeromorphs and VSMs Cerebrosphaera buickii, Svanbergfjellet, Draken Melanocyrillium hexodiadema, Backlundtoppen *Melanocyrillium sp., Backlundtoppen Osculosphaera hyalina, Svanbergfjellet *VSMs (=Melanocyrillium), Draken, Ryss6 * junior synonyms or equivalents

With more than 30 legitimate species of pre-Ediacaran ornamented acritarchs currently known there is a potential for resolving Neoproterozoic time on a much finer scale. A precise breakdown of assemblage zones has yet to be worked out, but already a clear distinction between Late Riphean and Vendian assemblages is emerging (Zang & Walter 1992; Knoll 1994). Moreover, there are a few forms that are sufficiently distinctive and widely enough known to serve as reasonably reliable index fossils. Vase-shaped microfossils (= Melanocyrillium), for example, occur world-wide across a broad range of facies and appear to be restricted to the latter part of the Late Riphean. The large acanthomorph Trachyhystrichosphaera aimika is even more widespread, so far reported from at least 15 localities, all with an estimated age of c. 700-900Ma (and possibly 750-850Ma); this biostratigraphic correlation has recently been corroborated by Sr and C chemostratigraphy (Kaufman & Knoll 1995).

chert shale shale shale shale shale shale shale shale shale, chert shale chert shale chert chert chert chert, shale

As with all acritarchs, the higher taxonomic affiliations of these fossils remains obscure; nevertheless, the morphological detail allows both their ready diagnosis and a considerably finer overall assessment than is possible with leiosphaerids. For example, large populations of the acanthomorph Trachyhystrichosphaera aimika in shales and cherts of the Svanbergfjellet Formation document a continuum of form indicating that eight previously named 'species' are merely ontogenetic and/or taphonomic variants of a single biological species (Butterfield et al. 1994). Moreover, in contrast to the conventional view of acritarchs being dormant cysts or spores in the plankton, several of the Svalbard acanthomorphs exhibit morphological features and an overall habit indicative of vegetative growth on or attached to the sediment surface, i.e. they form part of the benthos (e.g., Trachyhystrichosphaera, Cymatiosphaeroides, Germinosphaera). In the case of Germinosphaera, this habit (variable numbers of filamentous primordia originating from a single plane on the central vesicle) is remarkably reminiscent of the germinating zoospores of certain filamentous protists, including the modern xanthophyte alga Vaucheria (Butterfield et al. 1988, 1994). Unlike the abundant ornamented acritarchs of the Paleozoic which tend to measure 550#m in diameter, these pre-Vendian (as well as Vendian) forms tend to be very much larger, most often 100-500#m, and occasionally several millimetres in diameter (e.g. Trachyhystrichosphaera; Knoll, Swett & Mark 1991). As a grade of organization these large ornamented forms largely disappear by late Vendian time, possibly in a major extinction event (Knoll & Butterfield 1989; Knoll 1994). Whatever the cause, this distribution does provide a useful, if coarse biostratigraphic signal for the pre-Ediacaran. Thus, the occurrence of large acanthomorphs in metasedimentary rocks of Prins Karls Forland (western Svalbard) has greatly clarified the pre-Caledonian stratigraphy of that area (Knoll & Ohta 1988; Knoll 1992; Harland, Hambrey & Waddams 1993).

12.3.5

Multicellular protists (seaweeds) and problematica

Eukaryotic multicellularity stands as one of the fundamental innovations in the history of life. It is most commonly associated with Ediacaran and Cambrian radiations of large organisms, but its origins clearly lie well back in the Proterozoic. Svalbard fossils have contributed importantly to this early record, primarily from shallow-water shales of the Svanbergfjellet Formation (Butterfield, Knoll & Swett 1994). Multicellular eukaryotes and problematica reported from the pre-Vendian of Svalbard

Fossil taxon, higher taxonomy, formation Chlorophyta (green algae) Palaeastrum dyptocranum, Chlorococcales, Svanbergfjellet Proterocladus major, Siphonocladales, Svanbergfjellet Proterocladus minor, Siphonocladales, Svanbergfjellet Proterocladus hermannae, Siphonocladales, Svanbergfjellet Multicellular problematica Germinosphaera spp. ?Chromophyta, Svanbergfjellet Valkyria borealis, ?, Svanbergfjellet Macroscopic problematica Pseudotawuia birenifera, ?Metazoa, Svanbergfjellet Tawuia dalensis, ?, Svanbergfjellet, Kapp Lord The simplest Svanbergfjellet fossil that can be considered truly multicellular (as opposed to 'pluricellular' aggregations of unicells) is Palaeastrum, a colonial form in which the individual cells typically bore three to six differentiated intercellular attachment discs, very much in the manner of modern coenobial green algae such as Coelastrum and Pediastrum. Recognition of this cellular detail in the fossils allows their assignment to the chlorococcalean Chlorophyta, despite the absence of preserved pigments. On the same basis, the Svanbergfjellet fossils assigned to Proterocladus can be identified unambiguously as siphonocladalean green algae. These branched uniseriate filaments are characterized by irregular but generally very large (long) cells. In living organisms, such a pattern is characteristic of the multinucleate Siphonocladales (e.g., Cladophoropsis, Cladophora) where a distinctive cell division program known as 'segregative cell division' gives rise to an identical morphology. Proterocladus is divided into three species which are distinguished on the basis of filament diameter and details of septum and branch morphology. Along with Palaeastrum these represent the oldest fossil chlorophytes yet reported and provide a unique datum point for considering protistan, algal and chlorophyte phylogeny (Butterfield et al. 1994). Other multicellular fossils in the Svanbergfjellet Formation are more problematic. The most common and most complex is Valkyria, a large (100-1000 #m long) ornate form comprising at least 6 distinct structures. No convincing modern homologues or analogues have yet been identified, but if each of its separate structures represents a distinct cell-type, then Valkyria can be

PRE-VENDIAN HISTORY considered at least as complex as the most complex living alga or fungus (Butterfield et al. 1994). Moreover, it is not unreasonable to consider some or all of these constituent structures in fact represent tissues or organs, in which case the fossil would represent a grade of organization comparable to that of higher animals or plants. In any event, Valkyria is the most complex fossil yet described from preEdiacaran rocks. Pre-Vendian macroscopic fossils (> 1 mm) are known from both the Svanbergfjellet shales and carbonaceous siltstones of the Kapp Lord Formation on L5goya (Knoll 1982b). Most of these are identified as Tawuia, a large sausage-shaped fossil with a world-wide distribution through the Late Riphean and Vendian. Well-preserved specimens in the Svanbergfjellet show a distinct bi-layered wall construction (Butterfield et al. 1994), but otherwise offer little towards a resolution of their physiology or taxonomy--they might well represent an extinct lineage. Finally, there is a single specimen in the Svanbergfjellet Formation that is both macroscopic and conspicuously differentiated. This 1 cm long fossil, P s e u d o t a w u i a , differs from Tawuia proper in having a much thinner body wall and, at one end, a symmetrical pair of millimetre-long bean-shaped structures. In the absence of additional information the taxonomic affiliations of this fossil must remain speculative, but the possibility that it represents a simple vermiform (worm-like) metazoan is intriguing--fossil metazoans are currently thought to be Ediacaran, some 200 million years later.

12.3.6

Conclusion

In summary, the pre-Vendian Neoproterozoic rocks of Svalbard provide an unusually complete view of life between 700 and 800 Ma. Exceptional fossil preservation in diverse facies has allowed for detailed applications in taxonomy, phylogeny, biostratigraphy, palaeoecology, and palaeoenvironmental analysis, as well as to broad-scale considerations of biogeochemical cycling and Earth history. Closely correlative (and richly fossiliferous) units on East Greenland (Green et al. 1987, 1988, 1989) and Vendian sequences in the Polarisbreen Group of Ny Friesland (Knoll & Swett 1987) and Prince Karls Forland (Knoll & Ohta 1989; Knoll 1992) fill out the picture even further. Along with other benchmark biotas, the Svalbard fossils will continue to play a central role in reconstructing and overall understanding of the Neoproterozoic biosphere. Benchmark pre-Ediacaran Neoproterozoic fossil biotas, their estimated age (to nearest 50 Ma) and representative fossil types (in order of greatest stratigraphic utility; codes as for Subsection 12.3.1). Asterisk signifies Svalbard occurrences. See Schopf & Klein (1992, table 22.3) for references. Ages are approximate. 600 Ma AA, LA, MM *Scotia Gp, W Svalbard (Vendian) 600 Ma AA, PR, LA, MM Doushantuo, S China 600 Ma AA, LA, MM Pertatataka, C Australia 700 Ma AA, LA Biri Conglomerate, S Norway 700 Ma AA, ?VS, LA, MM Tindir, NW Canada *Roaldtoppen Gp, NE Svalbard 750 Ma AA, VS, MM *Akademikerbreen Gp, NE Svalbard 750 Ma AA, VS, PR, SW, LA, MM Eleonore Bay Gp, E Greenland 750 Ma VS, LA, MM 800 Ma AA, PR, LA, MM Wynniatt, NW Canada 800 Ma PR, LA, MM Little Dal, NW Canada 800 Ma PR, AA, ?VS, LA, MM Huainan, N China 850 Ma ?AA, LA, MM Bitter Springs, C Australia 850 MaS, ?AA, MM Chuar, SW USA 850 Ma AA, LA, MM Miroedikha, C Siberia ?950 Ma AA, SW, LA, MM Lakhanda, SE Siberia

12.4

Precambrian isotopic ages

Precambrian isotopic ages are collected here from the foregoing regional chapters where their geological context was explicit. For this particular study, which focuses on Precambrian history of

235

Svalbard, the precision of the numbers is less relevant than the presence or absence of evidence in particular areas for large segments of geologic time. Therefore, the critical petrogenetic and analytical data will not be repeated. Details will be found in the sources referred to if not in the earlier chapters. A dominant feature of isotopic ages in Svalbard is the widespread effects of pre-Carboniferous Paleozoic thermal events accompanying tectonism. These events, commonly referred to as Caldedonian, extend beyond the Caledonides and preceded the Silurian Caledonian climax of the Ny Friesland Orogeny, especially in the western terranes. From this standpoint there are two consequences: (i) earlier isotopic determinations generally by K - A r and R b - S r methods tend to record the latest thermal event to the exclusion of earlier events and (ii) some apparently anomalous early Paleozoic or latest Proterozoic ages appear to be the result of partial modification of still earlier mineral systems. There is thus no clear-cut Precambrian to Cambrian or Vendian gap in the isotopic apparent ages whereas the stratigraphic record suggests a lack of tectonothermal events. Indeed the Vendian record is unusually complete in Svalbard and gives little hint of igneous or metamorphic activity except in the western terranes. Therefore pre-Ordovician apparent ages must be considered as reflecting suspect Pre-Vendian events.

12.4.1

Eastern terranes

Two sectors have been described: northern Nordaustlandet and Ny Friesland (Chapters 6 and 7) and the Precambrian ages described in their stratigraphic context there are summarized here. Northern Nordaustlandet. Hamilton & Sandford (1964), by Rb-Sr, found mostly Paleozoic ages except for a granite pegmatite at Nordkapp in which feldspar was determined at 537 Ma, and from a schist at Rijpdalen, biotite gave 618Ma, Muscovite 636Ma and whole rock 581 Ma. Edwards & Taylor (1976) reported the age of a granite boulder in a Vendian tillite north of Wahlenbergfjorden as 1275 Ma. Goroshov et al. (1977) on Kapp Hansteen volcanics from Botniahalvoya obtained 766Ma later revised, to take account of the initial high Stontium content, to 970 Ma. Ohta (1992) to a compilation of earlier work added a result of c. 600 Ma. Gee, Johansson et al. (1995) gave U - P b and P b - P b zircon ages of c. 950 Ma for granites from Laponiahalvoya.

Ny Friesland. Gavrilenko & Kamenskiy (1992) by K - A r methods on ultramafic rocks separating the Polhem Formation from the Planetfjella Group obtained a value of c. 1.8 Ga, in northern Ny Friesland. Balashshov et al. (1993) by U - P b method in zircons from the Eskolabreen gneisses of southern Ny Friesland determined an age of c. 2.42 Ga, i.e earliest Paleoproterozoic. Gee, Schouenborg et al. (1992) by U - P b and 2~176 ratios on zircons from granitic gneiss, from the Bangenhuk formation of northern Ny Friesland Mesoproterozoic ages of c. 1.75 Ga Johansson et al. (1995) reported from Bangenhuk and Instrumentberget-Flgttan further zircon ages of 1720-1770 M a for gneissic granitic and aplitic rocks and 1737 Ma for gneissic granite, with the conclusion that intrusion took place at about 1750 Ma. Larionov et al. (1995) similarly reported on determinations of zircon ages from granitic gneiss in the Eskolabreen Formation of Ny Friesland, the lowest unit recognised. Values of 1766 4-10 match those of other Atomfjella Complex occurrences and an intercept of 404 + 8 suggests a Caledonian overprint of Siluro-Devonian age. Balashov et al. (1995) reported U - P b zircon ages. The upper intercept ages of zircon show this to be a reworking with inherited zircon of c. 2.5 Ga and of 1200 M a for acid volcanics with a regional metamorphism of e. 950 Ma. This Grenvillian result also fits Rb-Sr

236

CHAPTER 12

whole rock work on the pelites of the Isbjornhamna Group. The earlier 2.42Ga age (Balashov et al. 1993) for the same formation has not been detailed and must be in some doubt. Witt-Nilsson, Gee & Hellman (1997) reported c. 1740 Ma from the Instrumentberget gneiss and its derived boulders in the basal Polhem conglomerate. Gee & Hellman (1996) and Hellman et al. (1997) found the youngest ages from single detrital zircons to be 1190 Ma from the Smutsbreen Formation, and Polhem Formation, 1317 Ma.

WESTERN

CENTRAL

Ma

South

--700--

A

/k

-,,Tmn,4he~m6e"a . v . ~ . , ,j

~

Central north. The Richarddalen Complex in the Biskayerhuken peninsula has yielded a complex sequence of Precambrian ages. Early work on the eclogite reported by Gayer et al. (1966) gave K-Ar ages of clinopyroxenes from different samples of c.790, c. 823, 1399, 1435 and 1937 Ma. Peucat et al. (1989) concluded from U-Pb on zircons an Archean value of 3 2 3 4 + 4 3 M a , the rocks being reworked by later tectogenesis at 965 Ma and by subsequent tectogenesis from 661 to 402 Ma, with a possible 620 Ma emplacement of acidic magmas later than the well-known eclogite.

Pinkie

I

~=

Akademiker-IRoaldtoppe~

Q~

/

?

L ? Ordovician J

I

P~

A

Kongsvegen~

--'~

- - 800 - -

Nordaustlandet

Sofiebogen

A

--600--

/

Central terranes

:~ichardNy dalen Cpx. Friesland

-- 545

r Vestg6tabreen "] 12.4.2

EASTERN

N.V~ IN.W.

i

-o

breen

..S_. '~ Veteranen

-- 900

--

~

?

Kapp

Nordbukta

Hansteen

~ ] -- 1 0 0 0 - -

Regi~

metamorphism Eimfjellet and

_

_

?Planetfjellal _

Isbjornhamna --1100-ri~Isbjornharnna Grou~ (is below)

- 1200 - - ~ 0 ~

Eimfjellet Group Smutsbreen[

max. (is below)

Central northwest. The rocks of the Krossfjorden Group since Holtedahl's time have been regarded as Precambrian strata tectonised, metamorphosed, migmatized and intruded by granite in mid-Paleozoic time. However, an earlier zircon date has been rmnoured but not yet reported.

-1300-Polhem

max. -1400

- 1500

12.4.3

Western terranes

Oscar II Land. The target for determinations has been the Vestg6tabreen Complex, with blue schists, which has generally yielded Early Paleozoic ages. However a value of 2121Ma was obtained by Sm-Nd (Bernard-Griffiths, Peucat & Ohta 1993) but details remain to be reported.

--1600 . . . . . . . . . . . . . . . .

1-- -- -

-1700

Harkerbreen

-1800--

Southwestern Wedel Jarlsberg Land. The Isbjornhamna Group, west of Hansbreen has long been regarded as Precambrian basement and yielded, by K-Ar methods reported in Gayer et al. (1966), 565 and 594Ma. Peucat, Dallmeyer & Tebenkov (in Ohta 1992) have given ages without published details, by zircons of c. 1130-1135Ma. Balashov et al. (1995) reported U-Pb zircon ages. The upper intercept ages show this to be a reworking with inherited zircon of 2.5Ga and of 1200Ma for acid volcanics with a regional metamorphism of c.950Ma. This Grenvillian result also fits Rb-Sr whole-rock work on the pelites of the Isbjornhamna Group.

Finnlandveggen

-1900--

- 2000 inherited in Vestg6tabreen

? [2~0~

- 2500 inherited in

Eimt]ellet - 3000-I I

12.4.4

Sequence of Precambrian isotopic ages

Figure 12.5 presents a summary of Precambrian isotopic ages for western, central and eastern terranes, and shows consistent results at c. 1750Ma and 1700-1800Ma in Ny Friesland, with a possible equivalent age in Nordaustlandet. Reliable 950-960 Ma age have been reported from each of the three contrasting terranes in Svalbard. Some older numbers may be relict zircons from limited outcrops such that generalization is speculative. The younger ages may represent either a widespread event at about 600 Ma or the effects of mid-Paleozoic tectonism on older mineral systems. Ohta (1992) listed the ages naming them in terms of a sequence of orogenic events elsewhere: i.e. Saamian (3234Ma), LadoganBelomorian (2121Ma); Sveco-Karelian (1707-1668Ma); Grenvillian (1275-950 Ma). Thereafter the correlation attempted was with Svalbard events, a problem to be considered in the next section.

Fig. 12.5. Correlation of Precambrian sequences in the western, central and eastern terranes, with some age constraints. The international boundaries between Archean, Paleo-, Meso-, Neoproterozoic and Phanerozoic are drawn at 2500, 1600, 100 and 545 Ma respectively.The linear scales change at 2000 Ma. VKF, Vimsodden Kosibapasset fault.

Figure 12.5 plots some of these data which illustrates the general limitations of terrane comparisons on this basis.

12.5

Tectonostratigraphic evidence for proto-basement

Proto-basement is defined here as the product of Precambrian tectonism which ideally would be identified by a marked angular unconformity overlain by Precambrian strata. The term avoids the ambiguous 'Precambrian basement' which is commonly also

PRE-VENDIAN HISTORY

Fig. 12.6. Map showing the distribution of proto-basement in Svalbard, namely those rocks that were tectonised in some degree in Proterozoic time.

applied to Precambrian rocks tectonised in Phanerozoic time and so forming a basement to Phanerozoic strata (Harland 1997). Within the successions listed above it is pertinent to examine the evidence for Precambrian diastrophic events and in particular to establish any proto-basement that would identify tectogenetic and/ or tectonothermal elements of orogeny. Early this century all high grade metamorphic rocks were regarded as Archean and would have qualified as proto-basement until it was shown by Holtedahl (1914), and then by others, that mid-Paleozoic metamorphism affected most Precambrian successions and so complicates the problem. Each possible candidate for proto-basement is therefore considered on its merits. Conclusions are recounted here following the chronometric data from the previous section and the more detailed arguments of Harland (1997) (Fig. 12.6).

12.5.1

Eastern terranes (Province)

Ny Friesland. The 'Western Schists and Gneisses' of Fairbairn (1933) or the Stubendorffbreen Supergroup of Harland, Wallis & Gayer (1966) taken as a whole is rejected as proto-basement on the grounds that, in spite of some strike-slip faulting between it and the overlying rocks east of the Veteranen Line that divides the Veteranen and Planetfjella groups, they are concordant and to some extent conformable and transitional (Wilson 1958; Wallis 1966). Manby (1990) and Manby & Lyberis (1995) have argued for a major shear zone--the Eolusletta Zone separating the Veteranen Group and younger rocks from basement (i.e. proto-basement) below. It appears that their shear zone coincides with upper Planetfjella Group strata which, nevertheless, retain much of their stratigraphic sequence along strike. There is no doubt about the

237

sinistral shear and there is little doubt about the consistent stratigraphic continuity through the Veteranen and Planetfjella groups. However, within the Stubendorffbreen Supergroup the two lower groups have been referred to as the Atomfjella Complex and claimed by Abakumov (1965), Krasil'shchikov (1979) and Gee et al. (1992) in effect as proto-basement, the latter on the grounds of U-Pb zircon age values of around 1750Ma in the Harkerbreen Group and also in the Finnlandveggen Group (Larionov et al. 1995). As recounted in Chapter 7 the Planetfjella Group overlies the Harkerbreen Group over a N-S distance of about 150 km. In the north some of the upper Harkerbreen rocks are missing which might suggest an unconformable overstep in which perhaps 2.5 km, a 5% slope on the angular unconformity, which would agree with an igneous event, but hardly a major orogeny. Moreover, as pointed out (Harland 1997) the map adapted from Johanssen et al. (1995) (Fig. 7.4), which acknowledges mapping by Abakumov, confirms the above by plotting the upper formations of the Harkerbreen Group as they wedge out northwards against overstepping Planetfjella Group strata. This is conclusive evidence of an unconformity. However, there is sufficient consistency within the Harkerbreen rocks that the same succession is quoted from Harland & Wilson (1956) and Harland, Wallis & Gayer (1986) even by those proposing an orogenic episode to separate the groups into basement and cover, or into discrete thrust sheets. The igneous event could in part be of a different kind without entailing major tectogenesis. The stratiform granitic gneiss could in part be of meta-pyroclastic or ignimbrite origin. An acid lava flow or flows of such extensive stratiform nature or an igneous sill could fit the field observations. However, there are igneous intrusive contacts especially in the north which may either be the result of refusion of the protolith or more likely of associated granitic magma. Zircons could either be inherited in a volcanic source, but were claimed to be magmatic in origin from fusion of the lower crust. If the 1750Ma ages were contemporaneous rather than inherited it would suggest a long hiatus somewhere in the upper part of the Harkerbreen Group, because the overlying Planetfjella Group, with its acid pyroclastic component, seems to correlate well with the Kapp Hansteen volcanic and magmatic episode to the east in Nordaustlandet as was first suggested by Harland & Wilson (1956) and which has now been fairly reliably dated at c. 950Ma (Gorochov et al. 1977; Gee et al. 1995). A further problem concerns the Finnlandveggen Group below the Harkerbreen Group. The two constituent formations appear to continue the succession downwards without obvious discordance but undoubtedly with tectonic contacts. The concordance may stem from the intense Ny Friesland (Silurian) tectogenesis. It was first thought that if there were basement in the Hecla Hoek sequence it would be here. Indeed the Eskolabreen gneisses seemed to be likely candidates. However, the apparent consistency of the succession, as reported in Chapter 7 was to some extent confirmed by Balashov et al. (1993) who remarked on the apparent conformity between the Smutsbreen and Eskolabreen formations. Further data (Johanssen et al. 1995), supporting Gee et al. (1992) and reinforced by Larionov et al. (1995), established that the granitoids in the Atomfjella Complex comprising both the Harkerbreen and Finnlandveggen groups consistently yielded values around 1750 Ma, superimposed by Silurian metamorphism and tectonism and possibly with earlier relicts. The latest available information (Hellman et al. 1997) is that the minimum ages of the detrital zircons in metasedimentary rocks so far determined gave a value of l190Ma for the Smutsbreen Formation and 1317 Ma for the younger Polhem Formation. These are maximum ages of sedimentation. Therefore the sedimentary sequence of the Atomfjella Complex may not be significantly older than the Planetfjella Group and the unconformity between them need not present a major time hiatus. More detrital zircon data are needed from the metasediments. However, the original 'relatively continuous' sequence of Harland & Wilson (1956) has not yet been contradicted. The major problem remains as to the age and nature of the feldspathite layers all yielding c. 1750 Ma zircons and interstratified

238

CHAPTER 12

with the sedimentary sequence. The idea that all the feldspathites represented intrusions into older strata must now be abandoned and this leaves two clear alternatives: (i) as favoured by Helhnan et al. (1997) and Gee (1996) that the feldspathic units: Eskolabreen, Instrumentberget and Bangenhuk (including the associated and intruded Vassfaret Formation) represent one continuous basement with at least three nappes, each with their respective gneissic, basement and the overlying strata in their original order. (ii) as originally favoured by Harland, Wallis & Gayer (1966) that the feldspathites are not primarily intrusive, but metamorphosed ignimbrites etc. within the seemingly continuous sequence. Their metamorphism led to occasional melting and local intrusion. The consistent zircon ages at c. 1750 M a would have to be explained as a volcanic sequence deriving from the melting of a 1750 M a granite that gave rise to the uniform composition and zircon ages of the successive igneous events. Either model is just possible, but each has serious problems so that a third model may yet be needed when new data are available. Nevertheless, the conclusion here is that unconformities have been demonstrated structurally at the base of the Planetfjella Group and sedimentologically at the base of the Polhem Formation. The younger is a regional unconformity with minor diastrophism, but no tectogenesis and the older is demonstrated sedimentologically at only one locality.

Nordaustlandet. In Nordaustlandet the evidence for some basement is now clear. However, the similarities in the two successions are sufficient for their Precambrian proximity to be almost certain. The Murchison Bay Supergroup matches the Lomfjorden Supergroup in N y Friesland and both are apparently conformable below the Hinlopenstretet Supergroup of Early Vendian through Early Ordovician age. Thus, the Murchison Bay succession of about 6.6 km cannot be considered as basement. The Kapp Hansteen Group, already compared to the Planetfjella Group of Ny Friesland, comprises stratified volcanics and porphyry intrusions. These are followed, possibly in the same igneous episode by the Laponiahalvoya granites (Kontaktberget and Laponiafjellet). Altogether these thermal events seem to be well dated at about 950 Ma (Gee et al. 1995). The basal contact of the Murchison Bay strata has not been observed and there is the possibility that it may have been an unconformity following the igneous episode. Nor can the concordance of strata be adequately tested. So the Kapp Hansteen rocks and related granites cannot be ruled out as proto-basement. However, beneath the Kapp Hansteen Group an unconformity has been well established and referred to as the Botniahalvoya Unconformity (Gee et al. 1995). The underlying Brennevinsfjorden Group strata were folded before erosion, but without significant metamorphism. These Brennevinsfjorden strata could be equivalent to the Harkerbreen Group rocks in age but certainly not in facies. They could have been older. They have no obvious igneous component until they pass down into migmatites. These migmatites are related to further granites (east of Rijpfjorden) that postdate them. It remains to be established whether these migmatites and the related granites are Paleozoic (as isotopic data first suggested) or Precambrian for which there are some indications, as yet not tested by zircons. From the above it is concluded that the Kapp Hansteen and Laponiahalvoya groups are probably (Grenvillian) proto-basement and that the Brennevinsfjorden Group strata are certainly basement, possibly within the proto-basement. In other words that an unseen unconformity may separate the Kapp Hansteen Group from the units above it, confirmed by D. G. Gee (pers. comm.). As yet good zircon age determinations are still awaited for the rocks to the east of Rijpfjorden i.e. Duvefjorden Complex. By analogy it seems likely that as with the Laponiahalvoya granites, in spite of a Phanerozoic thermal event, the granites were emplaced around 950 Ma as would be the slightly earlier migmatites. The palaeosomes in the migmatites would thus represent the earlier basement rocks.

A feasible scenario is that, as long held by Russian geologists (e.g. Krasil'shchikov 1979; Turchenko 1987), the crystalline rocks at least of eastern Nordaustlandet are part of a Barents craton. On the above basis this might be a Grenvillian craton, and so the foreland of the Hecla Hock geosyncline to the west. All granites in the north eastern terranes of Svalbard have a continental affinity so that the Duvefjorden Complex (part of 'Barentsia') would be an extraneous projection from Laurentia. This theme is resumed in the next section.

12.5.2

Central terranes

Undoubted proto-basement is seen in the allochthonous thrust Richarddalen Complex of the Biskayer-

N o r t h Central Subterrane.

15--

BISKAYER PENINSULA

~c~ 1 0 v

"3 if}

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? , A t 4 -"-" -'380 Ma

I 400

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Temperature (~ NgVil Fig. 12.7. Pressure-temperature plot for the metamorphic complex of Biskayer Peninsula. Two metamorphic complexes are recognized: (1) the Richarddalen Group comprising garnet-hornblende gneiss, granitic gneiss, metabasic/ultrabasic rocks and garnet-bearing metagranite; and (2) the younger Biskayerfonna Group characterized by garnet biotite schist and interlayered amphibolite. The wide range of ages determined from zircon samples of undeformed granite form two populations, 3234 + 43 Ma and 965 -I- 1 Ma. The different mineral textures identified suggest a polymetamorphic history for the Richarddalen Complex. Similar age data have been defined for zircon from an undeformed metagabbro (955 4- 1 Ma), where these later ages provide evidence for Grenville-age deformation in Svalbard. Zircon age data from eclogite and diorite lenses show upper intercept values of 620-661 Ma and are inferred to represent crystallisation ages, and correlate with the maximum conditions of metamorphism for eclogite formation (vertical ruling). Retrograde alteration of eclogite is evident as a result of initial uplift and/or as a consequence of a later upper amphibolite facies overprint; 4~ data gives ages of 541 and 529 Ma. The uplift trajectory shown here clearly goes from the high-grade eclogite facies to a lower grade, possibly reflecting thermal overprinting. The Biskayerfonna Group indicates only a single metamorphic event dated as 430-380 Ma; no evidence of this is seen in the Richarddalen Group indicating emplacement following the Late Ordovician metamorphism of the Biskayerfonna Group (reproduced with permission from Ohta, Dallmeyer & Peucat 1989).

PRE-VENDIAN HISTORY huken Peninsula. The U-Pb zircon isotopic signature (Peucat et al. 1989) is complex. Prior to Caledonian reworking of the whole region recta-granites preserve an age of 965 + 1 Ma. Eclogites and felsic agmatite indicate latest Proterozoic magmatic or metamorphic events (661 + 2 and 625 + 5 Ma respectively). Subsequent metamorphism gave ages between 620 and 540Ma (Fig. 12.7). Cooling ages of 550 + 530 Ma by K - A r had been obtained (Gayer et al. 1966) and confirmed by A r - A r (Dallmeyer et al. 1990). Moreover, some zircons in a core of metagranite gave ages of 3234 -t- 43 Ma to 965 -t- 1. The conclusion of Peucat et al. is that 'the lower-intercept age of 965 4- 1 Ma corresponds to crystallization of zircon from the margins. The small amount of radiogenic lead indicates a component of Archean crustal reworking'. Several populations of zircons gave a mean Archean age of 3234 4- 43 Ma.

Northwest Subterrane. The major part of the terrane north of Kongsfjorden and (excepting the above complex) west of the Breibogen Fault is undoubtedly of Precambrian strata. Postdepositional thermal events were Caledonian as first claimed by Holtedahl (1914) the latest isotopic confirmation by Balashov et al. (1996). Moreover, the Kongsfjorden Group formations have a coherent correlatable sequence from the west coast to the Breibogen Fault so that any earlier major deformation must be precluded.

South Central Subterrane. The Magnethogda Group of metacarbonates and quartzites contains a distinctive feldspathic gneissose unit. On the terrane model postulated here neighbouring Vendian strata to the south are hardly metamorphosed and would suggest that the contrast probably indicates that this is protobasement. Comparison immediately to the west is across the postulated terrane boundary where Vendian strata are also only slightly altered. No detailed work on these rocks has been published nor is an isotopic age available. In this South Central Subterrane almost all other outcrops are of alleged Vendian age (Harland, Hambrey & Waddams 1993). South of Hornsund there are conceivable candidates which cannot for the present be usefully discussed or confirmed. These are the H6ferpynten Formation (which however seems to be concordant (though faulted) against the GSshamna (Vendian) Formation. Similarly the Mefonntoppane and Kistefjellet units are not obviously proto-basement but cannot be ruled out.

Early Varanger age. The structure and stratigraphy are, however, complex and subject to major differences of opinion as discussed in Section 10.7.1. The Isbjornhamna rocks were first analysed to give isotopic ages around 594 and 565 Ma by K - A r method (Gayer et al. 1966) and 1135-1130 Ma by unpublished determinations on zircons by Peucat, Dallmeyer & Teben'kov (in Ohta 1992). A further determination by Balashov et al. on zircons gave an upper intercept age at 2.5 Ga and by Rb-Sr reworking at 950 Ma. This is clearly pre-Vendian basement. It may well be part of the same complex with the Nordbukta Group only 20 km to the north. No correlation is evident, however, which may not surprise if these be inliers of an ancient and complex orogen. Forming the islands just west of the Eimfjellet Group outcrop is the Dunoyane (dolostone) Formation. This is of similar facies to the H6ferpynten Formation and most probably pre-Vendian. It could be a formation higher than the Pyttholmen Formation within the Eimfjellet Group or between that and the overlying (Vendian) tillites. The Sigfredbogen Formation south of Hornsund and probably west of at least a main splay of the Hansbreen Fault is a highly sheared psammite (and psephite) of limited coastal exposure. No stratigraphic affiliation is proposed here. It could be a fragment of the Eimfjellet-Isbjornhamna succession.

Oscar II Land. According to some opinions (e.g. Ohta et al. 1995) the Vestg6tabreen Complex and the newly interpreted Kaffioyra rocks (and by analogy the Pinkie Formation in Prins Karls Forland) could be regurgitated subducted fragments of Mesoproterozoic volcanics. They would thus be proto-basement thrust-up in Ordovician time. The difference in this work is only that the volcanic protolith, although identified from the same lower succession, is of Vendian rather than of Mesoproterozoic age. The age of the Lovliebreen volcanics was argued by Harland, Hambrey & Waddams (1993) to be early Varanger. This opinion has not been changed by later work so, interesting though these high grade metamorphic rocks are, they are not regarded here as proto-basement in the sense of this work (Harland 1997). It must, however, be mentioned that, along with consistent Ordovician metamorphic data, a zircon age of 2121 Ma was reported from the Vestg6tabreen Complex (Ohta 1992) but no details of that result are available for this work.

12.6 12.5.3

Western Terranes (Province)

Wedel Jarlsberg Land. In the northwest the Nordbukta Group is perhaps the best-established proto-basement in Svalbard in that a described sequence of formations has been folded, as is demonstrated by normal and inverted strata; truncated by a well mapped unconformity surface; and overlain by a thin conglomeraticcarbonate unit and followed by a diamictite, interpreted as the early Varanger tillite (Bjornerud, Craddock & Wills 1990). The Group is thus pre-Vendian but no further information has yet been obtained to constrain its age. The rocks are not conspicuously metamorphosed. In the southwest it is clear that the Eimfjellet Group (sensu Czerny et al. 1992) and the concordantly underlying Ishjornhamna Group at least are proto-basement. Recent isotopic age of acid volcanic clasts in conglomerates in the Pyttholmen Formation at the top of the concordant Eimfjellet Group show a 950 Ma age (Balashov et al. 1995). Similarly Balashov et al. (1996b) reported l l00-1200Ma zircon ages of the Skfilfjellet unit igneous component and that unit is just a bit below the Pythholmen unit in the Eimfjellet Group of Czerny et al. According to the interpretation here, although the contact is faulted the Eimfjellet is probably overlain by the Elveflya Formation (=Vendian tillite) of presumed

239

12.6.1

Pre-Vendian correlation Correlation within Svalbard

Turning now to wider regional correlation, the plot of pre-Vendian rock units (spread out in time according to available estimates) appears in Fig. 12.5. From this it would be difficult to demonstrate any similarity between the sequences in the three groups of terranes other than between the Vendian tillites and the c. 950 Ma thermal event referred to Grenvillian orogeny. On the other hand rather precise correlation is possible between Ny Friesland and Nordaustlandet in the east. In the west the best chance is in Wedel Jarlsberg Land where both in northwestern and southwestern outcrops, separated only by about 20 km, the same pre-Vendian hiatus appears. The established proto-basement is separated in the north by a clear unconformity in truncated folds of the undated Nordbukta Group and in the south by a fault (presumed to follow an unconformity) also from presumed Early Varanger tillites. But there is no obvious correlation between the southern Eimfjellet-Isbjornhamna sequence and the Nordbukta sequence. The hiatus represents a major orogenic episode named first by Birkenmajer (1975) as Werenski61dian. the precise application of this name must be in doubt because the time sequence of strata is not followed here (see Chapter 10) and he made direct correlation with Ny Friesland and Nordaustlandet

240

CHAPTER 12

assuming they were adjacent. His (1975) correlations of Akademikerbreen and H6ferpynten may well be correct as also with the upper Eleonore Bay Supergroup and the Porsanger Dolostone (of north Norway). But his Slyngfjellet-Veteranen, DeileggaPlanetfjella, Eimfjellet-Harkerbreen and Isbjornhamna-Finnlandveggen correlations are not favoured here whatever original distances separated them.

12.6.2

Pre-Vendian correlation beyond Svalbard

There is marked similarity of Late Proterozoic dolomite facies as of the Rysso, Backlundtoppen and H6ferpynten formations within Svalbard and the 'Limestone-dolomite Series' of the upper Eleonore Bay Group in East Greenland and the Porsanger Dolomite rocks of Finnmark. This suggests that at that time (?c. 750 Ma) a stable shelf shallow marine environment obtained in a wide region of similar eustatic and warm climatic conditions. In particular, the above correlation is conspicuous as between Eastern Svalbard and East Greenland, as in the overlying strata (Fig. 12.8). With regard to the proto-basement of Wedel Jarlsberg Land there is a simple comparison between the Svalbard indications of strata formed around 1200 Ma and subject to thermal influence at around 950Ma and the succession I of Trettin's (1987) Pearya terrane for which he reported crystalline basement with ages at 1.1-1.2 Ga. A later determination (Trettin et al. 1992) gave a zircon age for the crystalline basement of 950 + 2 Ma, and inherited zircon gave 2.1-2.2Ga ages. It will be recalled that from the Isbjornhamna Group, Balashov et al. (1993) reported U - P b ages of 2.4-2.5 Ga. These comparisons leave the door open to further work.

Fig. 12.8. Correlation of East Greenland and Ny Friesland Proterozoic sequences.

The above suggestions for external correlations might not by themselves be impressive, they are consistent, however, with similar comparisons in succeeding Vendian, Cambrian-Ordovician and Silurian periods.

12.7 12.7.1

Palinspastic considerations Global configurations

Pre-Vendian time is of such long duration that any attempt at palinspastic reconstruction could only reasonably be adopted for later Neoproterozoic time. Even in well-constrained configurations paleomagnetic APWP curves are fraught with uncertainties which are greater than the requirements to position the Precambrian fragments of Svalbard. The approach, then, is to consider available global reconstructions and it is more likely that Svalbard relationships will serve to refine the larger configurations than to derive help from them. It has generally been held that there was a Neoproterozoic supercontinent. For some time the Piper 1976model (1987) held sway until the SWEAT hypothesis of Moores (1991), Hoffman (1991) and Dalziel (1991) took the field. In each case the relationships between South American and African cratons were assumed throughout. The new development was to place Australia and Antarctica against western Laurentia. This relationship seems now to be well established but has little import for Svalbard. A secondary proposal was to adjoin western South America (Brazilia) against eastern Laurentia (including Greenland). Where Brazilia is made to fit in relation to Greenland it may appear to affect the position of S v a l b a r d - but the Svalbard fragments were in effect part of Greenland. Park (1994) took palaeomagentic data, plus outcrop evidence, into account with respect especially to Baltica and Laurentia. His model is shown in Fig. 12.9. Although this relationship was proposed for 1.9-1.6Ga it could have persisted until the Iapetus separation. The relationship would be consistent with the general conclusions in this work. Brazilia would have to be placed a little south along eastern Laurentia.

Fig. 12.9. Schematic reconstruction of eastern Laurentia and Baltica for the period 1900-1600 Ma, based on paleomagnetic model of Piper (1976), modified to include the northern British Isles and Rockall Bank. Ages in Ga give closest approximation to main tectonic activity. Reproduced with kind permission of Elsevier Science, Amsterdam, from Park (1994, fig. 1).

PRE-VENDIAN HISTORY At this point the application of the SWEAT or a derivative configuration to Vendian time is not accepted. However, preVendian time has too few constraints. Young (1995) argued that the break up of the SWEAT supercontinent took place in at least two stages roughly speaking Sturtian (c. 750Ma) (Fig. 12.10) and Vendian (c. 600Ma). His hypothesis was to account for the dominant distribution of glacial facies at c. 750 and 600 Ma. However, he suggested that the preSturtian supercontinent be named Kanatia and that the subsequent configuration retain the original name Rodinia. Baltica, during a similar time series, has been argued to rotate without reference to the supercontinent (Torsvik et al. 1992) and then in relation to Rodinia (Torsvik et al. 1996) These later reconstructions were initiated by dating the Varanger glaciation at 650653 M a in contrast to the North American Ice Brook glaciation at 575-580 Ma. This led Torsvik et al. to postulate two quite different orientations of Baltica to correspond to the (?coeval) glacials. However, both were at around 600 Ma, certainly with insufficient evidence to separate them. At the same time their A P W P indicated uncertainty for the pre-Ordovician segment. Soper (1994) suggested a further modification of the SWEAT hypothesis which he named BAZL (Baltica, Amazonia and Laurentia). Vendian Baltica was fitted against Greenland and Amazonia with the Torquist Line running parallel to East Greenland. This places northern Baltica a long way from where it might be in late Vendian time and would require a rapid anticlockwise motion which is the opposite of what Torsvik et al. (1996) required. It is suggested here that none of these configurations could reasonably be Vendian but some might work for earlier time. In pre-Vendian time there is little evidence to constrain relations between Svalbard (especially eastern Svalbard) and Baltica except possibly for the similarity of facies as between the Backlundtoppen

Fig. 12.10. Pre-Vendian aulacogen model showing the distribution of the Greenland, Barents and Baltica cratons.

241

and Porsanger carbonates. This would favour Baltica more nearly in a position at 750 M a as indicated in Dalziel's (1991) and Park's (1994) configuration shown here in Figure 12.10. This author, having worked a little in paleomagnetism, sets greater store by observable stratigraphic connexions than by apparent polar wander paths which may be weakly constrained except on a gross scale.

12.7.2

Svalbard relationships

Chapter 3 introduced the hypothesis of four Svalbard preCarboniferous allochthonous terranes, with subterranes, each related to a different original province in Greenland and one province including Ellesmere Island. The following chapters through Chapter 16 will consider this hypothesis in relation to evidence from successive time intervals. The hypothesis relates the eastern terranes of Svalbard to an early East Greenland province; the western terranes to north Greenland and the Pearya terranes of Ellesmere Island, the Central to an intermediate position off the present east of N o r t h East Greenland and, following Smith (in press), the southern terrane (Bjernoya) to a position near to easternmost N o r t h Greenland. It so happened that Precambrian (Vendian & pre-Vendian) stratigraphic comparisons provided the initial impetus to relate the eastern Svalbard successions with those of Central East Greenland. Indeed those who have worked on the stratigraphy of the both areas quickly became convinced of remarkable similarities, for example Kulling (1934) through Harland (1959), Swett (1981), Hambrey (1983), Swett & Knoll (1989). Whereas the Vendian comparisons have been made in some detail the pre-Vendian successions also suggest that they were formed in the same basin (Fig. 12.10). The lithostratigraphic similarities especially of the Lomfjorden and Murchison Bay supergroups in Eastern Svalbard and the Eleonore Bay succession in Eastern Greenland provide one of the several elements to unite the Eastern terranes of Svalbard with the Central East Greenland Province. The strength of the argument for such a connexion is augmented by similarities in subsequent intervals on to Silurian time. This postulated close connexion with East Greenland makes it unreasonable to fit the central and eastern terranes of Svalbard between eastern Svalbard and East Greenland at that time. Pre-Vendian isotopic age determinations of Svalbard rocks, valuable as they are to interpret the local succession, have tempted some scientists to favour such data for terrane comparisons. The data may be used (a) to argue for (or against) and distinguish between (or unite) allochthonous terranes in Svalbard. At the same time (b) the data may be used to test possible associations beyond Svalbard. (a) As already remarked the outcrops of pre-Vendian rocks are scattered and the opportunities to date the strata are limited and limited also by the field and laboratory facilities available which are in turn dictated by particular interests. The search for pre-Vendian tectono-thermal events has dominated the work in an effort to 'see through' the ubiquitous Ordovician and Silurian tectonism. In these circumstances remarkable strides have been made. Gee (1989, 1994) has championed the Grenvillian implications of c. 950 Ma ages. These seem to be relatively widespread so may not serve to discriminate palinspastically; but if and when reconstructions are acceptable then the Grenvillian story will be expanded. The result is a limited scatter of windows into earlier history. For palinspastic purposes age data may be significant, but not their absence. (i) The case for a terrane boundary between eastern and western Ny Friesland (e.g. Manby 1990, 1995; Gee & Page 1994; Gee, Johansson et al. 1995) has been shown to be difficult to sustain on tectonostratigraphic grounds (e.g. Harland et al. 1992; Harland 1995) and isotopic support hardly helps the case. A c. 950 Ma tectonothermal event in Nordaustlandet may well correlate with the Planetfjella group pyroclastic content in Ny Friesland, and the enigmatic 1750 Ma tectonothermal event in Ny Friesland cannot be excluded as related to proto-basement in Nordaustlandet.

242

CHAPTER 12 (e.g. 950-1275Ma of Ohta 1992). Gee (1989, 1995) has claimed this as evidence of a widespread Grenvillian event in Svalbard already known in Greenland. There is further evidence from Biskayerfonna (Richardalen Complex) and from the Eimfjellet Group (sensu Czerny et al. 1992) in southwest Wedel Jarlsberg Land. 'Grenvillian' tectonism may have been as widespread as early to mid Paleozoic tectogenesis in the Caledonides and beyond. The time spans are commensurate: 250-300 million years for GrenviUian events and about 180 million years to span Cambrian through Devonian time for Caledonian. The argument advanced by Gee is that much of Svalbard experienced a thermal event, not necessarily orogenic, and lay in the broad belt extending northwards from the Grenville province of north America. This does not conflict with the three-province hypothesis advanced here and might well support it. That the Grenville orogen triggered the opening of the ocean Iapetus may well be true, but Svalbard appears to have been on the American side of Iapetus and mostly not near its margin. Therefore the Svalbard data do not conflict with the hypothesis that Iapetus opened along that Grenvillian axis, is consistent with it, but hardly supports it. A problem is the long interval (?350 million years) between the events. The main opening of Iapetus was south and southeast of Central East Greenland. (b) The isotopic data may be applied to the three-province hypothesis to test whether ages in Svalbard might match those especially in Greenland or Ellesmere Island. This was considered (Harland 1997) who argued that so far as Central East Greenland is concerned there is such a wide scatter of determinations in East Greenland that at least the eastern terranes data could be matched but also probably many other ages. Strachan, Nutman & Friderichsen (1995) from zircon SHRIMP U-Pb determinations on rocks from the Smallefjord sequence (about latitude 75~ in southern North East Greenland found values in excess of 1000 Ma which they interpreted to be detrital. Values of 955 t 13 Ma were obtained for Grenvillian metamorphism and the beginnings of the multiphase Caledonian orogeny at 445 + 10 Ma (Ashgillian). Thus there is further evidence for the northern extension of Grenvillian metamorphism in a location that could have been parallel to both, and possibly intermediate between, eastern and central provinces of Spitsbergen. The exposed Caledonides in North East Greenland narrow considerably as compared with Central East Greenland, they are also less accessible, so that age data are sparse and hardly provide an adequate basis for comparison. Pearya, in Ellesmere Island, yielded few dates (Trettin 1987; Trettin et al. 1992). They included a Precambrian age: 950 Ma. Therefore it is consistent with the three province hypothesis here but it does not discriminate between the three terranes in Svalbard.

12.7.3

Fig. 12.11. Global palinspastic reconstruction for c. 750 Ma showing rift margins. (a) After Young (1995, by permission of GSA) Kanatia with glacigenic deposits (black triangles) marking the new Cordilleran rift; (b) after Torsvik et al. (1996, by permission of Elsevier Science) with both 750 Ma and 600-500 Ma rift margins shown. (ii) The c. 1750 Ma age of the Atomfjella Complex in Ny Friesland may enhance the comparison with East Greenland rather than North East Greenland where 'Grenvillian' intrusions and latest Proterozoic high P/T tectonothermal activity have been identified (Peucat et al. 1985) (iii) The c. 950 Ma event in Nordaustlandet (eastern terrane) may well match similar age data in Richarddalen (central terrane) and Isbjornhamna (western terrane). This age comes within the 'Grenvillian' time span

An East Greenland aulacogen

W h e n the ocean Iapetus, and especially its n o r t h e r n course, was proposed ( H a r l a n d & G a y e r 1972) the p r o b l e m of pre-Iapetus (Precambrian) geology was addressed. In m i n d was the thick preVendian geosyncline of East G r e e n l a n d and eastern Svalbard, estimated by them to have a c c u m u l a t e d over a time span of say 500 or 600million years. That calculation of sedimentation rates has been later supported by biostratigraphic 'guestimates' of the lower Veteranen formations and by correlation o f the Planetfjella G r o u p with the 9 5 0 M a K a p p H a n s t e e n G r o u p . Assume even a conservative estimate o f 300million years during which time subsidence proceeded at a rate c o m m e n s u r a t e with mantle cooling ( H a r l a n d 1969). W h e t h e r or not the subsidence was initiated by stretching of the crust, that was p r o b a b l y an initial phase a c c o m p a n i e d by acid volcanism. Spreading m a y n o t have continued at a similar (?constant) rate for a n o t h e r 100 million years. This East G r e e n l a n d - N o r t h East G r e e n l a n d basin or t r o u g h was intracontinental (ensialic). If it was a failed ocean, it was a successful geosyncline. This aulacogen rather than the later Iapetus ocean m a y have been a t e m p o r a r y spreading response to the Grenville t e c t o n o t h e r m a l activity. T h e spreading o f Iapetus m a y have been too late to be triggered by that orogeny, but the general heat a c c u m u l a t i o n beneath the Grenvillian crust of the ?supercontinent could still have contributed to Iapetus spreading.

PRE-VENDIAN HISTORY As it turned out Iapetus may have followed the course of the aulacogen to the south; but it departed to the northeast and so did not penetrate the East Greenland trough (Fig. 12.10). From a Svalbard viewpoint there is little to say about the convolutions of Baltica on the far side of Iapetus and, for that

243

matter also, little to constrain it before the opening. Attempts to match Precambrian orogenic belts between Laurentia and Baltica generally suffer too much 'tectonic slop'. Hence the old adage 'more work needs to be done'.

Chapter 13 Vendian History W. B R I A N 13.1 13.2 13.3 13.3.1 13.3.2 13.3.3 13.3.4 13.4 13.4.1 13.4.2 13.4.3 13.4.4

Vendian time scale and correlation, 244 Correlation of Vendian successions in Svalbard, 246 Vendian biotas, 248 Biotas from underlying rocks, 248 Biotas from the Gotia (Polarisbreen) Group in Nordaustlandet, northeast Svalbard, 248 Biotas from the Scotia Group in western Svalbard, 248 Biotas from Bjornoya, 248 Vendian environments, 249 Marine environments, 249 Vendian climates, 249 Glacial environments, 249 Volcanic environments, 251

The Vendian Period, the latest Precambrian division, and the earliest division in which several Phanerozoic methods of correlation can be applied, is a convenient time division for Svalbard. It is separated from the earlier history in which correlation has uncertainties of tens of millions of years if not more. The period is divided here into an early (Varanger) epoch and a late (Ediacara) epoch (Harland et al. 1990). The Varanger Epoch is documented by remarkably rich sequences, correlated throughout (but limited in Prins Karls Forland and Bjornoya) by the two distinctive major glacial episodes: the earlier Smgdfjord Stage and the Mortensnes Stage, with a substantial interglacial record between the diamictite horizons. The Vendian age of these glacigenic sediments is confirmed biostratigraphically. The Ediaeara Epoch is only confirmed from the Scotia Group in Prins Karls Forland, identified by a microbiota. A number of conformable post-glacial successions are plausibly of Ediacara age: the Dracoisen and Klackbergbukta formations in the northeast; the Annabreen Formation in Oscar II Land; the Peachflya and Geikie as well as the Scotia Group in Prins Karls Forland; and the Bogstranda and Ggtshamna Formations in Hornsund. Nevertheless the second part of Vendian time is as yet poorly demonstrated in Svalbard. According to the correlation followed here from Harland, Hambrey & Waddams (1993) based largely on the two glacial episodes, the outcrop area of Vendian strata is not small as shown in Fig. 13.1.

13.1

V e n d i a n t i m e s c a l e and c o r r e l a t i o n

Vendian, as used here, is the latest Precambrian time-interval preceding the Cambrian Period. Whereas Cambrian and other Phanerozoic divisions are internationally recognized and in many cases the boundaries have been standardized, the latest Precambrian division is still the subject of international discussion, as for example by the International Geological Correlation Programme Project No. 320, and there are other related projects. There was a need for CASP to have a series of named time divisions internally consistent and so far as possible internationally agreed (i.e. by IUGS) together with the best estimates of the age in years of the division boundaries. This need led to the participation of CASP with other geologists to produce what set out to be the best contemporary standard geological time scale. The first publication appeared in 1982 and a revised and enlarged work in 1990 (Harland et al. 1990). CASP followed Harland et al. (1990), which is reasonably stable except for the vexed question of the chronometry of the Precambrian-Cambrian boundary. In the 1989 scale it was placed

HARLAND 13.4.5 13.5 13.5.1 13.5.2 13.5.3 13.5.4 13.6 13.6.1 13.6.2 13.6.3 13.6.4 13.6.5 13.6.6

Tectonic environments, 252 Vendian international correlation, 252 Eastern Svalbard and East Greenland, 253 Western Svalbard and Pearya (Ellesmere Island), 253 Northwest Scotland, 253 Vendian relationships between Svalbard and Baltica, 253 Vendian palinspastic discussion, 254 East Greenland Province, 254 North East Greenland Province, 254 North Greenland, Ellesmere Island and Pearya, 255 The east North Greenland Province (Bjornoya), 255 The Iapetus Ocean, 255 Vendian palaeolatitude, 256

quite arbitrarily at 570 M a stating an uncertainty from 530 to 590. It now appears to be well defined. For the initial Cambrian boundary the chronostratic standard has been selected in Newfoundland at a point (GSSP) in a succession at Fortune Head, southeast Newfoundland, where the first record of Phycodes p e d u m occurs. The (pre-Tommotian) Nemakit-Daldyn division has been distinguished as the earliest Cambrian stage and, after many attempts its initial boundary was dated at about 544Ma by combined zircon methods (Bowring et al. 1993), or 545 Ma as used here from Tucker & McKerrow (1995). This result has major repercussions for the time scale in reducing significantly the duration of the Cambrian Period and extending the Vendian interval. There is as yet no reason to revise the initial Vendian boundary as given in 1990 at 610 Ma. Thus, we have a Vendian duration of around 80Ma, commensurate in duration with the Ordovician and Cretaceous periods. The division of Vendian time, and whether it is itself to be designated a period equivalent in rank to Cambrian, remain undecided. In the meantime the convention in Harland et al. 1982 and 1990 is followed (Fig. 13.2). All Pre-Vendian (Precambrian) divisions are less well calibrated and, except for the chronometric scale which has little application, remain to be decided internationally. Vendian, then, is the latest major time division preceding Cambrian time and the latest Proterozoic division, but not identical with Neoproterozoic III which was defined numerically as beginning at 650 Ma (precisely) and not related to any particular geologic events. Both Proterozoic and Neoproterozoic time intervals are defined somewhat anomalously. Their initial boundaries are based chronometrically at exact round numerical values and their terminal boundary is defined chronostratically at the Global Stratotype Section and Point (GSSP) in Newfoundland, currently estimated at around 545 Ma. A framework for a Vendian time scale is suggested in Fig. 13.2. It follows the international classification using priority of names as in the time scales of Harland et al. 1982 and 1990 rather than applying a regional scheme. The approximate Vendian division apportions the whole of the Vendian duration gained from Cambrian time, as a result of the initial 445 M a boundary, to the Ediacara Epoch. This extended time is divided as by Knoll & Walter (1991) with their detailed biostratigraphic and geochemical characterization. Whereas the Svalbard record has little new to offer the Ediacara time scale it is suggested that the Varanger record in Svalbard is probably not surpassed anywhere else. It was the basis for Kulling's (1934) enumeration of some late Precambrian glacial analogues in other parts of the world. More detailed study of the Svalbard Proterozoic glacial deposits and comparison especially with East Greenland and Norway resulted in (i) the confirmation that these diamictites were truly glacial (ii) the impression that they occurred within strata giving indications of hot climatic

VENDIAN HISTORY

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/

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Fig. 13.1. Vendianoutcropsin Svalbard,mainlyfromHarland,Hambrey& Waddams(1993).

,

100

76

246

CHAPTER 13 Era

~3'~ PDB

Period Animal fossils E P i ch

Tr ~ce fo~ ;sil

Acritachs

Glacials

Stage

"'Sr/'"Sr Ma

%0

-5 r t

I

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I

I

I

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Chronometric nomenclature

0.707 0.708 0.709 , I I I

Toyonian Botomian o

~ ~

mO {

~

Atdabanian Tommotian

Nemakit-C

530

--

540

Shelly fauna and

Daldyn (Lontova)

Rovno

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III

?

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.-

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. 3 1. - .

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.

.

.

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A Possible pre-Varanger metazoans

Kudash

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if:

environments (iii) the confirmation by palaeomagnetic reconnaissance that some were indeed low latitude and not the result of rapid polar wander (iv) the discrimination between the two Varanger glacial episodes and other earlier glacial episodes (v) the conjecture that a global glacial epoch prevailed at that time (vi) and consequently that, provided the ice ages could be distinguished by other means, they were valuable correlation horizons especially as between sedimentary successions and tectonized metamorphic terranes. The series of studies on Proterozoic ice ages (Harland 1983) had their inspiration in the well-displayed successions in Svalbard and the conclusion as to relative synchroneity of the two Varanger glacial episodes provide a basis for correlation within Svalbard (Harland & Wilson 1956; Harland 1964a, b; Harland, Herod & Krinsley 1966; Harland & Herod 1975; Harland, Hambrey & Waddams 1981; Hambrey 1983; Harland, Hambrey & Waddams 1993). The approximate age of the two Varanger glacials as between 590 and 610 M a (Harland et al. 1990) was based mainly on recent isotopic data from Newfoundland and accepted provisionally by Knoll & Walter (1991). The 653 M a age of the intertillite Nyborg Formation in North Norway was by whole rock R b - S r (Pringle 1973) and is not reliable because of detrital clay minerals though still applied by Torsvik et al. (1996).

13.2

o

/

Sm&lfjord V

isotopic variations of carbonate rocks (adapted from Knoll & Walter 1992; printed with permission from Nature 1992 Macmillan magazines Ltd).

N

n~ a. O

/ /

(~

O

/

Mortensnes

R

~

/

J

c

Fig. 13.2. Vendian biostragraphy and

2

.

Correlation of Vendian successions in Svalbard

Figure 13.1 shows the distribution of Vendian rocks in Svalbard according to this account. It is supported by the correlation chart (Fig. 13.3) which relates the principal rock units as described in the foregoing regional chapters and which will receive further comment in sections 13.4. and 5. The correlation chart is based on that by Harland, Hambrey & Waddams (1993), but rearanged so as to distinguish the western

Cryogenian

85o - - 900 Tonian - - 950

successions formed in a highly mobile environment, but outside the Caledonide realm, from those formed in a relatively stable environment but subjected later to Caledonian tectonism. The Varanger Epoch is recorded in far more detail than the Ediacara Epoch in spite of the probably much longer duration of the latter. The chart departs from that in Harland et al. because of the further reinterpretation of the succession in southwestern Wedel Jarlsberg Land. The Eimfjellet Group follows the sequence of Czerny et al. (1992) rather than that of Birkenmajer and is here regarded as unequivocally pre-Vendian (Chapter 12) in contrast to the overlying Elveflya Formation (= Vimsodden tillite). It should be cautioned that whereas the eastern sequences are generally accepted the others may well be controversial. There may not have been time for considered critiques by others of the Vendian synthesis of Harland et al. (1993). Within the southwestern Wedel Jarlsberg Land succession Balashov et al. (1995) reported new U-Pb zircon age data that confirm the interpretation applied here. The data are not well constrained but even approximate ages are useful. The detail is discussed in Chapters 10 and 12. The conclusion is that the Eimfjellet Group (of Czerny et al. 1992) includes the Pyttholmen, Gulliksenfjellet, Bratteggdalen Sk~tlfjellet and other formations still lower down. They are all south of the major fault zone (VKF) from Vimsodden to Kosibapasset whereas the Vimsodden, Jens Erikfjellet and Deilegga formations of the Aust Torellbreen Group are to the north of the fault and (here considered to be) much younger. The new age data refer mainly to samples in rhyotite conglomerates in the Pyttholmen Formation from which Balashov et al. Obtained ages of about 930 and 1200Ma. This confirms that the Eimfjellet Group (sensu Czerny et al.) is older, indeed early Neoproterozoic age and with relicts of Mesoproterozoic age. Thus there must be a significant time gap before the unconformable deposition of the Elveflya (Early Vendian) conglomerate. Consequently, as in northern Wedel Jarlsberg Land there was a major hiatus above the Protobasement and very thin Vendian strata beneath the lower tillite. This work follows Harland et al. in regarding the Jens Erikfjellet and

\

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VARANGER EARLIER

LATER VENDIAN

g

248

CHAPTER 13

Deilegga formations as younger than the lower tillite and approximately coeval with the Chamberlindalen and Dunderdalen formations to the north. This much is controversial. Although differing from land to land there is a similarity between them and a contrast with the more easterly successions. Seeking a single unifying name, Harland (1978) suggested the name Holtedahl Geosyncline from his early work in the key area of Oscar II Land. The Aavatsmarkbreen phyllites and schists regarded by Harland, Hambrey & Waddams (1993) as Vendian, may be Ordovician or at least have an Ordovician (Eidembreen) overprint (Ohta et al. 1996).

13.3 Vendian biotas Investigation of biotas from beneath and above the two tillite horizons confirms their Vendian age.

13.3.1

Siphonophycus inornatun, Zhang; Siphonophycus sp.; Myxococcoides spp.; Obruchevella Reitlinger 1959; ?Obruchevella sp. Poorly preserved acritarchs include leiosphaerid-like vesicles with an outward layer of hollow processes as have been described from late Riphean and Vendian strata are similar to Vandalosphaeridium from the Doushantuo Formation of China and Cymatiosphaeroides from the Pertatateka Formation of central Australia; these forms being of latest Proterozoic age. This is discussed more fully by Knoll (1992). From the known ranges of the other taxa 'the most likely age for the BCP beds is Late V e n d i a n - i.e. post-tilloid but preCambrian in age' (Knoll & Ohta 1988). That is an Ediacara age (Harland et al. 1990). Knoll & Butterfield (1989) tentatively suggested that large ornamented acritarchs, such as those in the Scotia Group, disappeared more or less coincidentally with the rise of the Ediacara faunas. Harland et al. (1979) had already placed the Scotia Group as later than the late Varanger tillite and pre-Ordovician or Silurian (the speculative age of the overlying Grampian Group).

Biotas from underlying rocks

Stromatolites and oncolites underlying glacigenic strata in Svalbard had already suggested a Vendian age for tillite deposition (Krasil'shchikov 1970, 1973; Raaben & Zabrodin 1969). Subsequently preliminary results from Precambrian microfossils confirmed this impression of the age of the Ny Friesland tillites (Knoll 1982a). Samples collected immediately below the tillite on Sore Russoya in Murchisonfjorden contained 'Bavlinella faveolata (Shepeleva)' Vidal (a pseudofossil), Trachysphaeridium timofeevi Vidal and Stictosphaeridium sp. in an assemblage nearly identical to that found by Vidal (1979) in shales from the Vendian tillite group in East Greenland. The tillites in East Greenland and northeast Svalbard are similar in many other respects (Knoll 1982). The above results, are consistent with the assumed age of the tillites of northeast Svalbard.

13.3.4

Harland & Wilson (1956) had suggested that the Polarisbreen tillite-bearing rocks might correlate with the Slate Quartzite Series, between the Younger and Older Dolomite Series, of Holtedahl (1920). Krasil'shchikov & Mil'shtein (1975) renamed the unit as the Sorhamna Formation beneath the Ymerdalen Formation (Ordovician) and overlying the Russehamna Formation. Harland, Hambrey and Waddams (1993) described the Sorhamna Formation as bearing small lone-stones (probably drop-stones) so increasing confidence in the 1956 correlation. Moreover, Krasil'shchikov & Mil'shtein (1975) described the underlying Russehamna Formation in five units thus: (5) (4)

13.3.2

Biotas from the Gotia (Polarisbreen) Group in Nordaustlandet, northeast Svalbard

The siliciclastic Backaberget Formation in Nordaustlandet overlies the Rysso dolostone Formation and underlies the Sveanor tillite. It has been correlated with the Elbobreen Formation (which contains the early tillite) in Ny Friesland. Indeed it appears also to contain elements of the early tillite in the (probably coeval) Langgrunneset succession to the north (Harland, Hambrey & Waddams 1993). In the shales Knoll (1982a) identified: Protosphaeridium sp., Trachysphaeridium spp. f stictosphaeridium sp. and Bavlinella the psuedo fossil. These are consistent with a Varanger age, i.e. midVendian sensu Vidal (1979a). Oncolite species Osagia svalbardica and the catagraph Vermiculites irregularis (ex Harland & Wright 1979) also suggested a Vendian age. But these may not be chronostratigraphically significant.

13.3.3

Biotas from the Scotia Group in western Svalbard

Whereas the Neoproterozoic sequence in northeast Svalbard is rich in microfossils and stromatolites, only one Proterozoic biota has been discovered in the west. This is not surprising considering the metamorphic grade of most of the rocks. However, in the Scotia Group of Prins Karls Forland, Knoll & Ohta (1988) and Knoll (1992) reported microbial fossils from chert nodules in a 'Black Carbonate Pelite' BCP which probably corresponds to the lowest of the three formations (i.e. Baklia Formation of Harland et al. 1979). The whole (tectonized incompetent) Scotia Group is in need of revision. The following taxa were described and figured: Eomycetopsis robusta, Schopf emend, Knoll & Golubic (1979); Eomycetopsis sp.;

Biotas from Bjornoya

10-20m grey massive sandy dolostone with relict phytolithic texture. 150-200m light grey dolostone with quartz sandstone laminae; transitional to (3).

At the top of unit (4) is their assemblage IIIB: Asterosphaeroides (?) ruminatus. Zabr.; Vesicularites lobatus, Reite.; V. compositus, Z. Zhur.; V. aft. botrydioformis, (Krasnop.): V. elongatus, Zabr.; V. enigmatus, Zabr.; V. vapolensis, Zabr.; V. Parvus, Zabr. At the bottom is assemblage IIIA of microphytoliths: Osagia maculata, Zabr; O. milsteini, Zabr.; O. pullata Zabr.; Vesicularites elongatus, Zabr.; V. raabenae, Zabre. (3)

80-120 m grey-fine grained dolostone with up to 5% quartz grains near top with 'Coagulation texture'.

(2) 50-80m alternating units (4-6m) grey massive dolostone and finely laminated dolostone with iron-stained partings. The bottom 15-20m is a distinctive marker bed with assemblage II: Osagia crispa, Z. Zhur; O. medwezhiella, Milst. and probably Radiosus aculeatus, Z. Zhur. are associated. (1) 150m grey medium-grained dolostone with assemblage 1 near top: Vesicularites lobatus, Reite. and Nubecularites, Masl. Krasil'shchikov & Mil'shtein argued that assemblages II and IIIA are similar to each other and to the Upper Riphean of Zhuravleva (?Sturtian) and that assemblage I is probably older. Assemblage IIIB compares with Yudoma assemblages, i.e. Vendian, and the less identifiable assemblage in unit 5 could be similar. Thus the upper part of unit 3 and units 4 and 5 are probably Vendian with downward transition. Harland, Hambrey & Waddams (1993) reported that the Ymerdalen Formation rests unconformably on the Sorhamna Formation. They concluded that the Sorhamna Formation is Vendian (Varanger) and that the underlying Russehamna Formation passed down into earlier Varanger, and then to Sturtian age. The biostratigraphic age conclusions from the above biotas, however, may not meet more stringent later criteria.

VENDIAN HISTORY 13.4

Vendian environments

Marine, climatic, glacial, volcanic and tectonic environments are selected for consideration.

13.4.1

249

scale in every case is from - 8 to +8 plotted against thicknesses. The positive values in theory might indicate loss of the lighter isotope to land-based ice. In practice they correspond reasonably to wellknown tillites and so presumably yield a climatic signature. In due course this promises a powerful correlation tool especially in Precambrian successions.

Marine environments

It is virtually certain that strata accumulated in prevailing marine environments rather than in isolated basins. This was on the basis both of the Hecla Hoek sequence in the northeast, which continued with little break for even hundreds of millions of years, and on the lack of near-shore sedimentary patterns (e.g. Harland & Herod 1975). This opinion was later confirmed by the finding that the salinity of the ambient water in which glacigenic sediments formed was similar to that of present-day oceans. High salinities are indicated by local occurrence of anhydrite relicts as in carbonate members of the Elbobreen Formation. High carbonate concentrations are evident from the rock flour derived from thick preceding carbonate formations exposed in a great area of shallow seas (Fairchild 1983). The northeastern Vendian outcrops reflect relatively shallow water with changing sea levels in response to Varanger glacial episodes. The western outcrops give evidence of deeper marine environments. Carbon isotope ratios in marine deposits also yield information on global climatic changes to be discussed (e.g. Knoll et al. 1986; Kaufman & Knoll 1995). Kaufman & Knoll made systematic comparisons of C-isotope values in a number of key Neoproterozoic sections worldwide. This work has already been referred to in the pre-Vendian successions. In each case Svalbard provided significant 613C data which are abstracted here in Fig. 13.4. The

~'~ C

f,f, o

l

100

-

200

-

-

300

-

-

400

-

-

500

-

,-?,;2 I

,0, ,2 , i , ~,, ,8

l

Oracoiserl

- 600 -

-

7oo

-

-

800

-

-

9OO

-

Wilsonbreen

Elbobreen

-lOOO

-

11oo

-

12oo

-

13oo

-

14oo

..~

..~

- 1500 .~ B a c k l u n d t o p p e n

-

1600

-

-

1700

-

-

1800

-

-

1900

-

-

2000

-

-

2100

-

-

2200

-

-

2300

-

-

2400

-

-

25oo

-

-

2800

Draken

S v a n b e r g ~ e l l e t

//

Grusdievbreen

Fig. 13.4. Secular variation in (~13C plotted against stratigraphic depth (m) for the Varanger and Sturtian succession of Spitsbergen (simplified from Kaufman & Knoll 1993 with permission of Elsevier Science, Amsterdam).

13.4.2

Vendian climates

Most palaeolatitudinal studies placed northeast Svalbard in Cambrian time in a near equatorial position as, indeed, applies also to coeval sequences in Central East Greenland, and probably also in northern Norway (e.g Harland & Bidgood 1959; Bidgood & Harland 1961; Harland 1964b). This is consistent with the thick pre- and post-Vendian carbonate sequences. Nevertheless dolostones may have formed in both warm and cold waters (Fairchild & Hambrey 1984). At the same time, the main Vendian outcrops all expose two distinct glacial horizons, named from the original Finnmark succession: Smfilfjord and Mortensnes combined in the Varanger Epoch (Harland & Herod 1975). Such an apparent anomaly led some to doubt the glacial nature of the tilloid deposits and others to doubt their tropical location as by rapid polar wandering. However, the hypothesis of two epochs of severe tropical, nearequatorial marine glacial deposits (Harland 1964a, b) has since been generally acknowledged (e.g. Frakes 1979; Chumakov & Elston 1989; Kirschvink in 1964, 1992). This carries with it the implication of at least two global glacial epochs, but it does not follow that tropical glaciation was synchronous with polar glaciation, especially if the main continental distribution at the time was in low latitudes. An independent isotopic assessment for Svalbard (Fairchild & Spiro 1987) suggested that oxygen isotopes may constrain palaeolatitudes of the Late Proterozoic glaciation. Pleistocene and Late Paleozoic glacials known to be polar give a known measure of 6180 on the basis that modern snow, glacier ice and meltwaters in high latitude are depleted therein. The isotopic compositions of ambient glacial seawater-meltwater maximum has unexpectedly heavy oxygen for a polar environment (Harland, Hambrey & Waddams 1993). Sufficient criteria are now generally accepted for identifying tilloids as truly glacial (formed in a variety of environments). Such tillites are often good marker horizons and may be distinguished even after severe tectonization and metamorphism. However, several other Neoproterozoic glacial horizons are known so that, it is essential to estimate the age proximally by lithocorrelation and distally by biocorrelation. Fortunately in Svalbard both these may be achieved. Moreover, the two tillite horizons in Svalbard may be distinguished by their stone content. The earlier is typically composed of intrabasinal clasts and the later by additional crystalline, often pink granitic, stones along with intrabasinal clasts. It so happens that Svalbard exposes extensive Vendian strata, often largely identified by tillites and tilloids. The correlation principle being that such extreme climatic excursions could not have been local, they must have been regional at least, and most probably global. Therefore correlation by these two glacial episodes does not imply original proximity.

13.4.3

Glacial environments

Svalbard Varanger deposits, especially in the northeast, present a remarkable opportunity to interpret glacial environments (Fig. 13.5). The facies are conspicuously different in the eastern and western outcrops. The latter are more difficult to interpret because of two subsequent tectonic episodes.

250

CHAPTER 13

Early Cambrian

strata. They were consolidated before erosion. Continuous glacial cover is suggested from lack of supraglacial debris. (iii) 'Interglacial' sediments. First a rise of sealevel (MacDonaldryggen Member E3) with offshore sedimentation and then a fall (Slangen Member, E4) are indicated. Oolitic and intraclastic grain stones, teepee structures, with fenestrae and anhydrite inclusions in chert, were observed. Breccia-filled wedges occur at the top.

TokammaneFm.

/ / / / / /'

Dracoisen Fm.

/ / / D6. / / / / / /. / / / / / / / / / .I I .

~

Shallowmarine l .~Emergent

~

Shallowmarine

D5 ~ D4

Ediacara

1Emergent

(iv) Sedimentation during second glacial (Mortensnes) (Wilsonbreen Formation, W1-3). A second major regression marks the onset

~l~Emergent ~ 1 ~ Shallowmarine

--

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9

1

Warm

Offshore

D2 D1

t Shallowmarine

il~

W3

Proximalglaciornarine ~ 1 ~ Groundedice

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Proximalglaciomarine Grounded ice Proximalglaciomarine

t

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.

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Glacial

Emergent

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"

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Elbobreen Fm, E~-.g.~,~-~

J

~ , /, El

Late Riphean

Backlundtoppen Fm.

I--I --I - II I

I--I / /

"qt-~" Distalglaciomarine Proximal glaciomarine ~1 Shallowmarine

} Glacial

] Tidal

, Warm

j

,/

Fig. 13.5. Interpretation of Vendian environments from the successions of Ny Friesland (northeastern Spitsbergen), based on data from Harland, Hambrey & Waddams (1993, table 20).

Eastern outcrops.

of glaciation (W1). The Wilsonbreen Formation exhibits all the glacial features of the first stage, but the scale and intensity were much greater. This formation cannot be overlooked because of the conspicuous exotic stones, often pink granitoids and many other lithologies in contrast to the strictly intrabasinal stones of the lower tillite. Chumakov (1968) described a glacial pavement within the boulder-rich diamictite succession. The Middle Carbonate Member (W2) with stromatolites and rhythmic limestones, interpreted as periglacial, divides the typical till facies into two (Wl and W3). (v) Post-glacial sedimentation (Dracoisen Formation, D). A trangressive succession follows beginning with a basal conglomerate. A surf zone discontinuity followed by shallow, sublittoral wavedominated fine-grained dolostones, D1, fine upwards into offshore mudstones D2 and D3. This is followed by regression with ephemeral lakes, desiccation cracks, silicified anhydrite nodules and halite pseudomorphs. A return to marine conditions is shown by dark shales with acritarchs below the sub-Cambrian discontinuity (A.H. Knoll in Fairchild & Spiro 1987). It is noteworthy that an almost identical sequence occurs in East Greenland (Fairchild & Hambrey 1995).

The evolution of the evolving environment is summarized in Fig. 13.5 based on studies by Hambrey (1982), Fairchild & Hambrey (1984) and Fairchild & Spiro (1987). It was a period of deposition of fine-grained sediment in a slowly subsiding basin or shell punctuated by the influx of coarse material by glacial transport from a distant source. There is no record of tectonic instability nor of volcanic activity. The sequence of events may be summarized in the following five stages (Harland, Hambrey & Waddams 1993) redescribed in sequence stratigraphic terminology by Fairchild & Hambrey (1995). (i) Pre-glacial sedimentation (Elbobreen Formation, El). Through Sturtian to early Vendian time limestones and dolostones predominate and are interbedded with sandstones and mudstones. Stromatolites, dolostones, oolites, pisolites and limestones with shrinkage cracks are widespread.There may then be a hiatus representing Vidal's (1985) early Vendian microflora and the lack of negative 513C values. (ii) Sedimentation during first glacial (Sm~ffjord) stage (Petrovbreen Member E2). Lodgement and waterlain tillites predominate with material mainly from the upper Backlundtoppen Formation and above. A fall in base-level is interpreted to provide erosion of local strata. Features include: glacio-lacustrine rhythmites with dropstones; periglacial wedge fillings; fluvioglacial and debris flow conglomerates; dolostones of rock-flour. Provenance from SE to SW sectors suggests uplift of rocks similar to underlying

Western outcrops.

Although largely tectonized the same two tillite horizons in the sequences, but an order of magnitude thicker, may be distinguished as in the east. The upper one is conspicuous, resistant and often with exotic stones. The lower tillite with stones of calcareous composition similar to the matrix may be overlooked. Nevertheless occasional critical sedimentary structures are preserved to confirm a glacial origin: dropstones at Kapp Martin and Vimsodden; original shapes of lone-stones; fine extensive laminations; outsize stones are dispersed therein; great thickness and extent (Harland, Herod & Krinsley 1966). The stones form a smaller proportion of the total clasts, typically 1-5%, but up to 50%. There are no abraded rock surfaces (as in Ny Friesland). The environment suggests ice rafting into highly mobile distal turbidite facies often with flame structures. Uplift and reworking of till material concentrates and results in fluvial conglomerates. Steep submarine slopes enabled transport of cobbles, the oolitic matrix coming from a shallow marine environment. Study of sediments, as above, may suggest local environments. A regional or global study of coeval strata may give some clue as to the global influences affecting the local environment. A Varanger global glaciation has already been suggested which would most likely require i.a. a reduction in atmospheric CO2. Of alternative and contributing mechanisms Young (1995), while not denying that the Varanger glacials (at about 600 Ma) could be global as indeed also the Sturtian glacials (at about 750 Ma), suggested that the best development of the Varanger glacials occurs along the North Atlantic-Arctic seaboards whereas the Sturtian glacials dominated the western margin of Laurentia and neighbouring Australia as juxtaposed in the SWEAT hypothesis. He argued a break-up of the SWEAT supercontinent in two stages. The earlier assembly (named Kanatia by him) was separated at about 750 Ma by fission between Laurentia and Australia and Antarctica. The later assembly (Rodinia) at about 600 Ma separated Baltica and Amazonia from Laurentia (with Greenland). He suggested that the initial rifting first splitting Kanatia and then Rodinia localised the glacials. He pointed out the long-observed double glacial episodes in each case

VENDIAN HISTORY as though there might be similar tectonic causation which he discussed. His actual maps of Kanatia and Rodinia, however, would not accommodate the palinspastic relationships developed in this work.

13.4.4

Volcanic environments

We have no record of volcanism during the formation of the Polarisbreen Group rocks of northeast Svalbard. Volcanic stones (e.g. amygdaloidal basalt) of unknown age were reported in the Sveanor tillite of Nordaustlandet. On the other hand the west coast successions are conspicuous by their basic igneous component. Orvin (1940) referred i.a. to outcrops of gabbro, along the west coast south of Isfjorden, which on investigation, in spite of later tectonism, could be shown in most instances to be contemporaneous within the succession. All the main outcrop areas of Vendian rocks in the west have a significant volcanic content as follows (e.g. Kovaleva 1983; Turchenko et al. 1983).

Oscar II Land. Within the St Jonsfjorden Group, i.e. well beneath the upper tillite, are two formations with basic components. In the lower part of the Lovliebreen Formation is the conspicuous basic amygdaloidal lava formation. On Gunnar-Knudsenfjella foliated dark brown, green and purple rocks are exposed and also occur extensively in the neighbouring moraine and, indeed, through southern Oscar II Land (Harland et al. 1979). Ohta (1985) referred to these as Trollheimen volcanics, describing their lavas as up to 15 m thick with calcite amygdales, possible pillow structures, and associated with interbedded pyroclastics at Trollslotten in upper Eidembreen. Chemically these rocks are calc-alkaline and Ohta suggested a non-oceanic type, possibly formed in a shallow marine setting in association with shelf-edge sediments. Some pyroclastic rocks are reddened suggesting contemporaneous weathering. Some of the finer metasediments within the formation, typically phyllite, appear to have some basic content. The overlying Alkhorn Formation has a less conspicuous igneous aspect; but contains distinctively Na-alkaline basites, also with pillow structures (Ohta 1985). North of St Jonsfjorden are near-coastal exposures of the Aavatsmarkbreen Formation, at the top of the Comfortlessbreen Group and well above the upper (Haaken) tillite. Between its upper and lower divisions, of grey-black phyllite and marbles, is an incompetent middle division of up to 100 m of dark grey, green and black slate and light green fibrous serpentinite. At Snippen soft, light green and purple banded shales may be seen. A distinctive volcanic component thus characterizes this formation also to some extent in the lower division (Harland, Hambrey & Waddams 1993). Subsequently, Ohta et al. (1995) have shown this to be part of the newly identified Kaffioyra Complex of Ordovician metamorphism and Paleogene shearing, but the correlation here of the protolith as Early Varanger still holds. With such extensive volcanic rocks in the St Jonsfjorden Group it is not unlikely that the Vestg6tabreen Complex represents a Vendian protolith. It is a tectonic slice of blue-schist facies, intensively studied because of the high pressure mineral assemblage. Demonstrated biostratigraphically as pre-Caradoc and isotopically as mid-Paleozoic, it is now suggested that of the pre-Vendian strata known in the west none have been reported with a volcanic component. Therefore it must be considered that the complex may have been (?subducted) rocks of the St Jonsfjorden Group. This could be tested geochemically (contra Harland, Hambrey & Waddams 1993). Prins Karls Forland. The oldest rocks are the up-thrusted metamorphic complex of the Pinkie Formation. The age is uncertain but a case was made for it to correlate with the St Jonsfjorden and equivalent groups further south, not least because of the metavolcanic component (Harland, Hambrey & Waddams 1993).

251

The Alasdairhornet Formation, consisting of banded and welded tufts and some basic lava flows, belongs to the Peachflya Group which is well above the Ferrier Group (with distinctive diamictite, probably Late Varanger). These rocks are difficult to correlate in detail with the Vendian succession in Oscar II Land just across the water. The Kaggeu Formation of the Scotia Group, already distinguished by its Ediacara fossils, is the middle formation, conspicuous for its grey, green-purple and striped slates and phyllites which reflect a fine-grained volcanic component. It was correlated with the Aavatsmarkbreen Formation across Forlandsundet.

Nordenski6ldkysten. The stratigraphic succession in this strandflat has been variously interpreted, e.g. by Turchenko et al. (1983), Hjelle et al. B10G (1986) and Harland, Hambrey & Waddams (1993). Regardless of the succession the older maps show the promontories Diabaspynten and Gronsteinodden on the southwest coast. These are closely associated (interstratified) with tilloids. Whereas Turchenko et al. and Hjelle et al. considered them to belong to the top of the succession, Harland, Hambrey & Waddams, distinguishing two tillite horizons, argued these to be of Early Varanger age. On the second hypothesis they could correlate with the St Jonsfjorden volcanics; but in any case they are of Varanger age. Hjelle (1962) noted the similarity of the basites in Nordenski61d Land and in Chamberlindalen to the south, in northern Wedel Jarlsberg Land. Turchenko et al. (1983a, b) remarked on the geochemical similarity of the same rocks with metabasites at Vimsodden and still further south. They described green schists with basic volcanic derivation, intrusive and extensive gabbro, andesite and andesite-basalt. Harland, Hambrey & Waddams (1993) further noted a similarity with the Lovliebreen rocks to the north in Oscar II Land.

Northwest Wedel Jarlsberg Land. Of the two groups of formations accessible from the coasts east and west of Kapp Lyell the Kapp Lyell Group (Late Varanger) has little or no volcanic component, whereas the underlying Konglomeratfjellet Group includes the Chamberlindalen Formation whose (lower) Asbestodden Member is dominated by basic igneous rocks, including pyroclastics, lavas (some pillow) and small intrusions. Pelites and carbonates are interbedded with the volcanic rocks. The middle and upper members also have a similar though proportionately less conspicuous volcanic component. Turchenko et al. (1983b) described: 1300-1500 m schistose andesite-basalts and tufts; 500-1800 m andesite-basalts and picrites with sills of gabbro and peridotite, and dolostone; 150-200 m marbles with basalt and andesite basalts, transformed into green schists. Also diabase, gabbro and peridotite dykes; some pillow structures. The Chamberlindalen Formation is part of the eastern limb of a northerly gently plunging syncline. Where the strata reappear at the surface to the west they are not so well exposed and have been given a different name (Dunderdalen Formation). Some elements may have been cut out; but more likely (as seen further south) there are sharp east-west changes of facies in a highly mobile environment.

Southwestern Wedel Jarlsberg Land (south of Austre Torellbreen). The considerable differences between authors as to the succession, outlined in Chapter 10, will not be repeated here. The questions are unresolved. Naturally this account follows the conclusion of Harland, Hambrey & Waddams (1993) with some modifications. However, it is possible if desired using the following nomenclature to transpose the rocks described to the different implied time scales. The effect of these differences is that whereas the bulk of the basites described below are taken here as of Early Varanger age, other authors would make them mostly pre-Vendian.

252

CHAPTER 13

The Elveflya (Vimsodden) Formation is rich in green schists, interpreted as tufts and lavas, interbedded with diamictite. They were described by Smulikowski (1968) with further notes by Birkenmajer (1991) and Harland, Hambrey & Waddams (1993). The formation appears to pass upwards (northeastwards) into the Jens Erikfjellet (volcanic) Formation (map unit 32 B12G in Ohta & Dallmann 1991). The SkSlfjellet Formation (subgroup) is made up largely of basic igneous material (Smulikowski 1968). It had been regarded as an eastern lateral equivalent. It is now established as a Mesoproterozoic unit in the Eimfjellet Group of Czerny et al. (1992). Harland, Hambrey & Waddams (1993a) grouped all these rocks together with the overlying Deilegga and Slyngfjellet rocks in a thick and complex Werenski61d Group. On this basis it would be equivalent to the Konglomeratfjellet Group to the north. To avoid confusion, a new name, Austre Torellbreen Group, is preferred here. It may be recalled that the Scotia Group of Prins Karls Forland is of established Ediacara age and is also associated with purple as well as black slates.

strata, even though there may be some hiatus or non sequence. The changes in facies appear to reflect mainly sea level and climatic changes. These circumstances make it reasonable to postulate that the close similarities between the Ny Friesland and East Greenland successions are indeed the result of glacio-eustatic changes keyed in by the ubiquitous double Varanger glacial epochs with their concommitant changes in 613C compositions (e.g. Fairchild & Hambrey 1995). In the west of Svalbard, the contemporary mobility with turbiditic resedimented conglomerates (Waddams 1983) has already been stressed. In northwestern Wedel Jarlsberg Land a Late Varanger sequence of at least 3 km and about 3 km of Early Varanger strata rest with strong angular unconformity on an overfolded sequence. The impression of most observers (e.g. Bjornerud 1990) is that provenance of western deposits was in the east (not then in present-day Svalbard). In Southwest Wedel Jarlsberg Land the Early Varanger strata exceed 7 km in thickness and reflect volcanic facies. It also appears that normal tillites occur in the western outcrops as in the Elveflya Formation, but that only approximately coeval conglomerates (of similar composition) occur in the eastern outcrops and at a higher stratigraphic level. Therefore it would seem that still further to the east the early tills or tillites were uplifted, eroded and transported to be exposed now in the eastern outcrops. The Vendian outcrops east of Hansbreen give the impression of a relatively stable sedimentary environment; but they are not extensive enough to determine a direction of provenance. Thus rapid subsidence (and volcanism) characterises the western terranes in contrast to those in the centre and east.

Sorkapp Land. Winsnes (1955) described the GSshamna (phyllite) Formation as having a volcanic component. It lies beneath fossiliferous Cambrian strata and stratigraphically (with a tectonic break) above the H6ferpynten Formation. The latter is probably pre-Vendian. Harland et al. (1993) agree with Birkenmajer (1960 et seq.) in correlating G5shamna with their Bogstranda Formation to the north which they place above the Fannytoppen and Fannypynten formations (of Late Varanger age). On balance they regarded the GSshamna phyllites as most probably Late Vendian (Ediacara).

13.5

Bjorneya. The green and purple colour of some of the Sorhamna (?Vendian) Formation suggests a small volcanic component.

13.4.5

The Vendian Period is exceptionally well represented in its earlier (Varanger) epoch which reflects the two major glaciations. These enable international correlation, being distinguished from other Neoproterozoic glacial epochs by sufficient biostratigraphic control. Figure 13.6 shows approximate correlations between the various lands surrounding Svalbard. Of these all show a somewhat

Tectonic environments

In the northeast of Svalbard, the Vendian strata reflect a stable tectonic environment, and so do the preceding and succeeding

SPITSBERGEN 1

Vendian international correlation

GREENLAND

FINNMARKEN

, KOLA PENINSULA4 Western

East2

Northeastern

North 3

Paraut~176

(Sredniy Peninsula) i

BULLBREEN

OSLOBREEN

CAMBROORDOVICIAN

5

]

-J

Dracoisen

Spiral Creek Canyon

Wilsonbreen

Storeelv

Region 6

'

Portfjeld

,

CambroOrdovician

~

~

'

Brelvik . . . .

u~ Aavatsmarkbreen

AREA

SOUTHERN NORWAy7

Barents Sea

Berlev~g ." ~

Stappogledde

r

.,,.-~,

WESTERN SCOTLAND 8

Jura Quartzite

~AGE CAMBRIANSILURIAN

Vangsgs

,,,,, Illll

Ekre

Annabreen

Bonahaven Dolomite

O< <

E,

O ~;

Haaken

Moraenese

Mortensnes

Moelv

o

___ _.~, _ z q u_

Alkhorn

me~

Leviiebreen

E" '~

E4

Moefjellet

nO

E3

Trondheimrlella

Arena

Elbobreen E2 /~

?. . . . . M~illerneset + Z Nielsenfjellet < (.9 Steent]ellet .......

~I Z Bogegga

AKADEMIKERBREEN

~

rll

Puman

!

Motka / Kuyukan

conformity

.

-'

.

Z < 5 >

<

if)

Ring ,. ~..

,. " "

Birl Islay Limestone

~

~ ~ ~) 19&20 O ~ ~ ~ ,,, Bed below

z

9 orA Lu 9"r

"~[

15& group

uncomormi v

Port Askaig Tillite

Sm&lfjord

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,,J, ._E,

LOKVIKFJELL (or fm.)

Nyborg

O

Ulvese /~ i

E1

~'I~'I~ . . . . . . . .

Ill

......

~i

--

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Mullach Dubh phyllites

~ Biskop~s

. Inuiteq Se

KILDIN

.

.

.

.

.

TANAFJORD

BARENTS SEA

Br~ttum

Lismore Limestone

Z ~< Cull Bay Slates Ballachulish & Lochaber

Subgroups

*~ ~ -~ LU:~ r Late Riphean Sturtian

[~

Fig. 13.6. Vendian correlation chart for representative successions of Svalbard and adjacent areas of the North Atlantic-Arctic region (redrawn from Harland, Hambrey & Waddams 1993). Triangles are Varanger tillites.

VENDIAN HISTORY EAST GREENLAND Kl~tely Formation

253

NE S V A L B A R D Tokammane Formation

D6 :D5

A

~--~

D4

9 ._~.

~-~

I' I~

\

~

~,

"A~, Svalbard '~~, Terranes

~i

8

D3

o Canyon Formation

?

?

?

D2

o Storeelv

Formatio~ E4

T g

Arena Formation

Ulves~ Formation

E3

E ,?

E2

"Bed-group"19

"Bed-group" 18

Fig. 13.8. Schematic palinspastic model for Vendian time showing the inferred positions of the Svalbard terranes and the Iapetus Ocean. TKFZ, Trollfjord-Komagev Fault Zone. Hiatus

Unconformity

Fig. 13.7. Correlation of the Vendian successions of East Greenland and northeast Svalbard (simplified from Fairchild & Hambrey 1995, with permission of Elsevier Science, Amsterdam).

similar sequence related especially by the tillite horizons. However, the East Greenland-East Svalbard successions reveal an especially close match which is worthy of further consideration (Fig. 13.7).

13.5.1

Eastern Svalbard and East Greenland

Those who have worked on the stratigraphy of both Svalbard and Greenland (e.g. Kulling in the thirties, Harland in the fifties and sixties, Swett, Hambrey and Fairchild in the seventies and eighties) all agreed that the similarity between the successions in Eastern Svalbard and in Central East Greenland, are more than coincidental. The tillite Group has been described by many including Hambrey & Spencer (1987) and Moncrieff (1989). The Vendian sequence in each area is summarised in Fig. 13.6 (From Harland, Hambrey & Waddams 1993). The most detailed comparison was restated by Fairchild & Hambrey (1995). The two sequences must have belonged to one common basin and the thick, mobile and volcanic facies in western Spitsbergen could not then have occupied a position between them. Figure 13.8 shows a palinspastic model for Vendian time, indicating the inferred positions of the Svalbard terranes.

13.5.2

Western Svalbard and Pearya (Ellesmere Island)

The Pearya composite terrane (Trettin 1987)juxtaposes four distinct successions (terranes). Succession I is the crystalline basement with no clear Vendian analogue. Succession II of 'Upper Proterozoic

(?)-Lower Ordovician metasediments and metavolcanics "comprises" five different rock types: (1) a predominant suite of original shelf sediments such as limestones, dolostone, quartzite and mudrock; (2) diamictite and related greywacke and mudrock that are probably glaciogenic; (3) mafic volcanics, analysed samples of which are sub-alkaline basalt; (4) siliceous partly alkaline volcanics and (5) cherts'. The whole is mainly in greenschist facies. Succession II is younger than the crystalline basement (1.0 to 1.1 Ga) and on the top rests Early Ordovician. This matches rather well the western Svalbard Vendian sequence as outlined above. Succession III is clearly Ordovician and is discussed below (Chapter 14) and succession IV is also an Ordovician complex. Taken alone the similarity of facies in succession II and western Svalbard are noteworthy but might not have been noticed were it not for the striking Ordovician similarities. 13.5.3

Northwest Scotland

The correlation chart (Fig. 13.6) shows the Argyll and Appin groups of the Dalradian sequence together spanning more than Vendian time (Anderton 1982). The original Port Askaig Tillite is almost certainly Varanger in age but more precise correlation has not been forthcoming. 13.5.4

Vendian relationships between Svalbard and Baltica

Correlation from the viewpoint of Baltica was surveyed by Nystuen (1985). A convenient summary of the Barents Shelf margins was written by Hambrey (1988). The Varangerfjord region, Filmmark is the classic area where two tillite horizons in the Vestertana Group: Smgdfjord and Mortensnes are found. This Late Proterozoic succession, with some biostratigraphic control and resting on metamorphic basement of the Baltic Shield, has provided the

254

CHAPTER 13

stratotype for the Varanger Epoch. Thence the two tillite horizons are correlated. Whereas these comparisons make time-correlation virtually certain, they tell little about their proximity. The hypothesis of global glaciations at that this time (e.g. Harland 1964a) arose first from the comparisons between Greenland, Norway and Spitsbergen. Widespread refrigeration would be liable to deposit ice rafted stones into a wide variety of host sediments over enormous areas of sea as well as producing ice sheets on land, so that unless the provenance of the stones could be established not much can be said about proximity from such comparisons. Nevertheless the double glacial impact has proved to be a key in correlation between fossiliferous and metamorphic terranes. The Barents Sea Group is the c. 9 km succession north of the E - W Trollfjord-Komagelv Fault Zone in the north of Varangerhalvoya. It has no known stratigraphic base: the top is covered unconformably by the 6.5km Lokvikfjellet Group. Both groups appear to have Vendian or more likely Sturtian isotopic ages. In any case no correlation elswhere seems to be feasible (e.g. Bugge et al. 1995). The Ryhachiy and Sredniy peninsulas in Russia to the east have a similar relationship to the Baltic Shield, but ages are uncertain at Rybachiy. In the Sredniy peninsula the Volokovaya Group is probably Vendian with boulder horizons which might be fluvioglacial. A K - A r age from a basite dyke suggests an age earlier than 580 Ma. The Southeastern White Sea region. Whereas no particular lithic correlation with Svalbard is intended, subsurface material yields one of the richest Ediacara (Late Vendian) biotas anywhere.

13.6

Vendian palinspastic discussion

The two Varanger glacial events are represented in the three distinct terranes that are part of the palinspastic hypothesis developed in this work (see Fig. 13.8). Indeed perhaps the earliest requirement for such a hypothesis was the contrast between the Eastern (Polarisbreen) succession of stable sedimentation totalling less than l km and the coeval western facies with 10km of disturbed sedimentation and volcanics. The latter could not easily fit between Eastern Svalbard and East Greenland. It had to be elsewhere (Harland & Wright 1979). From a Vendian viewpoint the three Svalbard terranes are related to Laurentia as follows.

13.6.1

The East Greenland Province

The stimulus from which the hypothesis began was the perceived similarity between the East Greenland and East Svalbard successions as known personally and confirmed by several others who have known both areas. Degree of proximity may be argued but the unanimity remains. The contrast between the western terranes and East Greenland or eastern Svalbard would make an intermediate Vendian position for western Spitsbergen unlikely. Moreover, within northeastern Svalbard there is Vendian continuity across Hinlopenstretet so that there is no reason to divide this Eastern Province terrane into Vendian sub-terranes.

13.6.2

The North East Greenland Province

In much of North East Greenland the ice sheet approaches the coastline leaving a strip of the exposure narrower than in East Greenland to the south. Two terranes are distinct: the eastern terrane continues the East Greenland Caledonian Orogen and the western terrane is part of the foreland, perhaps representing the edge of the Laurentian craton. The western foreland is the platform onto which the Caledonian thrust sheets advanced from the east. It supports a mainly carbonate succession, late Precambrian through to late Silurian.

That cover succession is better known in North Greenland as part of the same platform succession. In the eastern fragment of the Greenland Caledonides there is some extension of the pre-Vendian Eleonore Bay Supergroup from the south and to the north. The orogen continues into Konprins Christian Land where westward verging thrust sheets contain a Late Precambrian sequence in the Hagen Fjord Group, 4 - 5 k m , with eight units namely: phyllite, marble, greywacke, sandstone, sandstone and ?tillite, limestone, dolostone and sandstone (Henriksen & Higgins 1976). The Ulveberget sandstone, 20-35m, contains 1 m ?tillites. The underlying Rivieradalen sandstone, 1500+ m carries some conglomerates. The Vendian through Ordovician and Devonian succession, so well represented in the eastern part of the East Greenland Caledonides, is thus missing here. It was postulated that the central provinces of Svalbard would have occupied a position in Vendian time east of North East Greenland. It is suggested here that Central Svalbard terranes might be parts of the missing North East Greenland Caledonides. Be that as it may, some aspects of the Svalbard Central Province are reviewed below. Vendian Eastern and Western terranes of Svalbard are distinct enough. However, Harland & Wright (1979) inserted a Central Province between them. Its characteristics are somewhat intermediate. Its boundaries are clear in the east where the Billefjorden Fault Zone separates the Eastern from the Central Terrane. The Central Basin covers the pre-Carboniferous rocks of the Central Terrane dividing into two parts: North Central and South Central. The Vendian story is not constrained in north Spitsbergen where only Devonian (?+latest Silurian), and pre-Vendian rocks are known. Thus in northwestern Spitsbergen any Vendian strata would have been deposited well above the Krossfjorden Group and would have been removed by denudation during the main Caledonian Orogeny. In south Spitsbergen, especially north and south of Hornsund, pre-Vendian through Devonian rocks are displayed. Vendian interest focuses on the outcrops east of Hansbreen and at its snout. The slightly overturned succession there, in the nomenclature preferred here, is as follows. Cambrian formations (east) contact not exposed: presumed faulted unconformity Bogstranda phyllite etc 2500 m Fannytoppen dolostone member 14 m Fannytoppen limestone member 80 m Fannypynten diamictite 500 m unexposed tract at neck of tombolo ?300 m Hansvika diamictite 500+ m 1 km gap at Hansbreen snout representing strike-slip fault Skfilfjellet Subgroup rocks (west) Harland (1978) and Harland, Hambrey & Waddams (1993) followed Birkenmajer (1958 et seq.) in correlating the Bogstranda phyllite with the G~shamna Formation (possibly Ediacara-Late Vendian). But (contra Birkenmajer) they correlated the Fannypynten tectonised diamictite (rich in granitoids) with the later Varanger tillites and the Hansvika diamictite, without granitoids, with the Early Varanger tillites. They are tectonised and, in the eastern exposure of the Skgtlfjellet subgroup rocks at the snout of the glacier, are highly sheared with associated sinistral structures. A major strike-slip fault was postulated to occupy the Hansbreen glacier front in the 1+ km gap between the Skfdfjellet and Hansvika rock exposures. This fault would separate the Varanger tillite and intertillite successions to the east, with a likely thickness of about 1500 m and with no sign of volcanic facies, from the western sequence of at least 7 km of mobile and volcanic facies argued by Harland, Hambrey & Waddams (1993) to be Early Varanger. Harland & Wright (1979), in proposing three terranes (provinces), argued for the existence of a fault, the Central West Fault Zone (CWFZ). It could not generally be seen, not only because major shear zones are rarely exposed, but mainly because

VENDIAN HISTORY the Paleogene West Spitsbergen Orogeny had obscured it by overthrusting from the west. The CWFZ would be traced from Kongsfjorden in the north through Recherchebreen and out to sea at Torellbreen in the south. On that basis all the area south of Torellbreen including the whole of the Werenski61d Group would have belonged to the Central Terrane. However, subsequent work, (Harland, Hambrey & Waddams 1993), argued that the Werenskiold Group (here the Aust Torellbreen Group) and related rocks belonged to the western sequences. They proposed the boundary fault to follow Hansbreen. They renamed it the KongsfjordenHansbreen (hypothetical) Fault Zone (KHFZ). That realignment was proposed largely on the basis of Vendian studies and made the rocks to the west belong to the Western Terranes, related to Pearya. The appearance of the sheet B12G (Ohta & Dallmann), however, has raised a question about the northward trace of this proposed Hansbreen extension of the Kongsfjorden Fault Zone. The exposures in middle Wedel Jarlsberg Land between Austre and Vestre Torellbreen are mapped as Cambrian west of the proposed KHFZ. This is really a Cambrian problem for the next chapter but is mentioned here because the course of the original Central West Fault Zone may well be more complex with splays in both Torellbreen and in Hansbreen and a further offset in middle Wedel Jarlsberg Land. 13.6.3

North Greenland, Ellesmere Island and Pearya

Ellesmere Island. Pearya is the name given to the strip of northern Ellesmere Island by Trettin (1987) for a composite terrane distinct from the rest of Ellesmere Island. Its close similarity to the Oscar II Land terrane in Svalbard has been generally noted and a degree of proximity has been widely accepted. It is hardly controversial except possibly in so far as Harland, Hambrey & Waddams (1993) argued that the whole of the west Svalbard terranes (south of Kongsfjorden) would also belong. Vendian geology is only part of the evidence for proximity as will appear (Chapter 14). For those who may not share the Paleozoic sinistral displacement hypothesis advanced in this work Spitsbergen was in any case agreed to be north of North Greenland before its Cenozoic separation. North Greenland and Ellesmere Island. Pearya occupies a position, striking E-W and north of the rest of the Canadian Arctic Islands and of the North Greenland (Trettin 1991, chapter 4). It is the northern-most element in the Franklinian Mobile Belt south of which is the Clements Markham Fold Belt, a deep-water sedimentary volcanic subprovince mainly Early Cambrian to Late Silurian. The Hazen Fold Belt and then the Central Ellesmere Fold Belt lies further south (see Fig. 16.10). The Sverdrup Basin (Carboniferous through Paleogene) developed on top of the Franklinian Mobile Belt and all rest on Precambrian basement of the Canadian Shield. Discussion of these relationships will recur in Chapters 14 to 16 because the strata are Cambrian through Devonian and lack Vendian. But this later history is consistent with the West SvalbardPearya connexion. Restoring Geenland closer to Canada, by reversing the opening of the Labrador Sea and Baffin Bay, and restoring deformed Ellesmere Island to a pre-Eurekan Orogeny configuration, would simply accentuate this more northerly position of Pearya. Vendian rocks which predominate throughout the Western Province suggest that at least three sub-terranes obtained. A Forlandsundet Fault Zone is, perhaps, an obvious occupant of the sound between Prins Karls Forland and Oscar II Land. The Vendian strata on each side are similar; but differences are more than would be expected from their present proximity. It is now clear that a Paleogene fault zone within the graben separated the two sub-terranes. It is likely that, as elsewhere, the locus of Paleogene dextral movements was determined by pre-Carboniferous sinistral displacement. Strong support for this view is afforded by the extreme sinistral shearing of (probably Moefjellet) dolostones at

255

the southwest promontory of Oscar II Land and the shearing and elongation of tillite stones in eastern Prins Karls Forland. A Torellbreen (splay) Fault Zone is proposed to separate the northwest from the southwest developments of Vendian strata in Wedel Jarlsberg Land. This is the southern part of the original CWFZ. It is probably a fault zone or zones, locating dextral Paleogene activity, but more fundamentally separating the two western outcrops of Vendian strata. In the north west Early Varanger strata rest unconformably on truncated recumbent folds, and in the south Early Varanger strata may well exceed 7 km. Therefore, at least three western sub-terranes are proposed: (i) northwestern (Prins Karls Forland), (ii) central western (Oscar IX Land south to northwestern Wedel Jarlsberg Land) and (iii) southwestern i.e. Wedel Jarlsberg Land between Torellbreen and Hansbreen.

13.6.4

The east North Greenland Province (Bjornoya)

The Vendian exposures of Bjornoya are about 300km south of those in Hornsund. It would not, therefore, be expected to find identity of facies with any of the three terranes of Spitsbergen. On the other hand the thin Vendian succession between younger and older strata of carbonate facies contrast strongly with Western Terrane successions. The Vendian affinity with the central or eastern successions would thus be considered to some extent indeterminate, perhaps closer to the central terranes. However, the Ordovician facies and conodont faunas suggest a close affinity with the sequence in north eastern-most North Greenland (Kronprins Christian Land) and within the Caledonian Belt (Paul Smith in Section 11.5.1).

13.6.5

The Iapetus Ocean

There is considerable affinity between Vendian Svalbard rocks and those of Greenland, but apart from the presence of tillites it has not been suggested that any part of Svalbard was at that time close to Baltica (Fig. 13.9). Cambrian and Ordovician biostratigraphy suggests that an ocean existed between Laurentia and Baltica which closed with the Caledonian orogeny. It would be difficult, if not impossible, to argue that such an ocean separated Greenland and Svalbard. Therefore in formulating the northern continuation of a Paleozoic ocean between the old and new worlds Harland & Gayer (1972) proposed the Iapetus ocean to separate Laurentia with Svalbard (including Bjornoya) from Baltica. Whereas the closure of Iapetus is well-constrained, its opening is not. Harland received funds from the Natural Environment Research Council i.a. to test the presence of such an ocean in Varanger time from the glacial deposits in Ny Friesland. There was evidence that these were formed from grounded ice (e.g. Chumakov 1968) and with a south easterly provenance. If this were established grounded ice could not have crossed an ocean and would suggest that Iapetus did not then separate Svalbard to the southeast. The results of the fieldwork in 1981 and 1982 were not so conclusive because provenance was also indicated from the southwest, but it seemed reasonable to conclude that Iapetus did not then exist and opened later (Hambrey 1983). From consideration of the Scottish Dalradian sequence, Anderton (1982) also concluded that Iapetus could not have opened before the tillites were formed. He preferred an initial Cambrian opening as suggested by the Tayvallich volcanics. Certainly Iapetus seems to be well documented paleontologically in Early Cambrian (Siberian) time (McKerrow, Scotese & Brasier 1992). There was certainly no ocean between Svalbard and Greenland during Neoproterozoic time. The earlier eugeosynclinal phase of the Hecla Hoek development was more likely in an intracratonal aulocogen, or Proto-Iaptus already discussed in Chapter 12. This author concurs with the opinion of McKerrow, Scotese & Brazier (1992) in regarding the palinspastic SWEAT hypothesis as

256

CHAPTER 13 estimated above (Fig. 13.2) at about 50-60 million years, we have little detailed record of events. Indeed this lack of a fuller record may reflect uplift with opening of Iapetus. See also Drinkwater, Pickering & Siedlecka (1996). The discussion above is based on Greenland and Svalbard stratigraphy. However, as a major ocean, Iapetus has figured in global reconstructions from quite different perspectives. Grunov, Hanson & Wilson (1996) argued that the closure (by subduction) of Pan-African deformation belts (sensu lato) opened lapetus between 600 and 500 Ma. This is not a tight constraint, but at least it is not inconsistent with the evidence above. Unrug (1997) outlined a model for the changes from Rodinia to Gondwana which (incidentally) showed Iapetus opening between Greenland & Baltica, and separating these two from Amazonia, between 600 and 500 Ma. The East European Craton is depicted by E U R O P R O B E (Gee & Zeyen 1996) as a Proterozoic basement bounded on the southwest by the Phanerozoic mobile belts (and separated by the Trans-European Suture Zone), on the northwest by the Scandinavian Caledonides, and on the east by the Uralides. It supports the East European Platform and exposes the Precambrian terranes of the Fennoscandian Shield (Baltica) and the Ukranian Shield. E U R O B R I D G E is a planned deep seismic traverse between these two shields which may then confirm that the East European Craton is undivided except by partial rifts. The significance of the above for this work is that Phanerozoic Baltica is in effect the whole East European Craton. But this does not necessarily apply to Precambrian configurations. It must be concluded that for Vendian time sufficient data to constrain the history of the relative positions of Laurentia and Baltica, separated by a wide Iapetus are not yet available.

13.6.6

Vendian palaeolatitude

Attempts were made unsuccessfully to obtain palaeomagnetic latitude from a large collection of Hecla Hoek oriented samples made in 1958 by D.E.T. Bidgood. However, a similar extensive palaeomagnetic operation in East Greenland, courtesy of Lauge Koch in 1957, while in some respects disappointing, did suggest that the East Greenland tillites formed in tropical latitudes (Bidgood & Harland 1964) and this was seemingly confirmed from Varanger tillites in northern and southern Norway (Table 13.1; Harland 1964; Harland & Bidgood 1959). Table 13.1 Vendian palaeolatitudes

East Greenland South Norway North Norway

Fig. 13.9. Global palinspastic reconstruction for c. 600 Ma (Rodinia) time showing the distribution of Varanger glacigenic deposits (black triangles). (a) After Young (1995, by permission of GSA) and (b) After Torsvik et al. (1996, by permission of Elsevier Science).

applied to Baltica and Brasilia in relation to Laurentia as not applicable in Vendian time, whatever its merits may be for preVendian Rodinia. Perhaps equally the Vendian antics of Baltica (e.g. Torsvik 1995) hardly constrain palinspastic models for Laurentia, including the fragment that became Svalbard. It is reasonable to suppose that the Iapetus Ocean opened or began to open in Late Vendian (Ediacara) time or in Early Siberian (Nemakit-Daldyn or Aldanian) time. Certainly in this span between recognizable (Varanger) tillites and (Late Siberian) olenellids,

Present position

Virtual pole position

Palaeolatitude

73~ 61~ 70~

4~ 161~ 18~ 179~ 15~ 5~

8~ 1~ 4.5~

25~ l l~ 30~

These low latitudes were not unexpected because all pre- interand post- tillite sedimentation suggested tropical environments into which the glacial incursions were exceptional. However, most scientists at the time discounted the evidence on the grounds that the tilloids were not glacial, that the determinations were at fault, that the magnetic field at that time was not bipolar, or that extremely rapid polar wandering produced two such anomalous excursions. Whether or not the relatively unsophisticated measurements on an instrument made for the purpose in the Cambridge Department of Geology were reliable, Torsvik et al. (1996) suggested a value of 30~ for the intertillite Nyborg Formation of Finnmark. Low latitude glaciation at that time is now more generally accepted (e.g. Frakes 1979). Even if tropical latitudes for Svalbard prove to be mistaken (Smith et al. 1997) the argument for Vendian tropical glaciation is sustained on sufficient evidence, as in Australia.

Chapter 14 Cambrian-Ordovician history W. BRIAN H A R L A N D 14.1 14.2 14.2.1 14.2.2 14.2.3 14.2.4 14.2.5 14.2.6 14.3 14.3.1 14.3.2 14.3.3 14.3.4

Cambrian-Ordovician time scale, 260 Cambrian-Ordovician biotas and correlation, 260 Bjernoya, 260 South Spitsbergen Cambrian and Ordovician faunas, 260 Northeastern Svalbard, 262 Oscar II Land, 264 Prins Karls Forland, 264 Correlation within Svalbard, 264 Cambrian-Ordovician sedimentary environments, 264 Dominant lithologies, 264 Distinctive Early Cambrian facies, 264 The Mid Late Cambrian non-sequence, 265 Ordovician facies in south Spitsbergen, 265

14.3.5 14.4 14.4.1 14.4.2 14.4.3 14.4.4 14.4.5 14.4.6 14,5 14.5.1 14.5.2 14.5.3

Cambrian-Ordovician history is well documented in Svalbard with late Early Cambrian faunas and a range of Ordovician faunas to provide a basis for correlation. Not so extensive as Vendian, the rocks crop out in four areas: (i) only slightly deformed strata in the youngest Hecla Hoek (Oslobreen) Group in northeastern Svalbard yield especially rich Early to Mid-Ordovician faunas. (ii) The Hornsundian Geosyncline in south Spitsbergen with more variable facies and tectonic complications also exhibits Early Cambrian and Canadian strata. (iii) The Bjornoya succession reveals a marked hiatus between Vendian and Early and Mid-Ordovician strata. (iv) In western Svalbard the lack of Cambrian and Early Ordovician strata marks a distinct Mid Ordovician tectono-thermal event to be followed by ?Late Ordovician and Early Silurian strata. Indeed the above four areas correspond to distinct terranes which, having different affinities especially with areas in Greenland, give evidence

BJORN~YA

OSCAR II LAND

Comparison of Ny Friesland and Hornsund facies, 265 Cambrian-Ordovician tectonic environments, 266 Northeast Spitsbergen, 266 South Spitsbergen, Eidembreen tectonism, 266 Bjernoya, 266 Oscar II Land, 266 Prins Karls Forland, 268 Forlandsundet Graben, 268 Cambrian-Ordovician terranes and palinspastics, 268 Supracrustal comparisons, 265 Tectono-thermal events, 270 Conclusion, 271

of relatively distant areas and environments of formation. Evidence of Cambro-Ordovician volcanism is not recorded. Figure 14.1 lists the successions in the four areas mentioned according to the classification of rock units as abstracted from chapters 6, 7, 8, 9, 10 and 11, where their regional settings may be found. The outcrops are plotted on Fig. 14.2. The northeastern Svalbard strata are separated by Hinlopenstretet. This waterway divides Ny Friesland and Olav V Land in Spitsbergen from northwestern Nordaustlandet and occupies a syncline, but the successions although differently named are essentially continuous. In southern Spitsbergen the fjord Hornsund separates the successions to the south in Sorkapp Land from those in the north in eastern Wedel Jarlsberg Land. The biostratigraphic evidence for correlation is discussed in Section 14.2 and plotted in Fig. 14.4.

SORKAPP LAND & EASTERN WEDEL JARLSBERG LAND

NY FRIESLAND

NORDAUSTLANDET

ANDREELAND GROUP

BILLEFJORDEN GROUP (Late Famennian)

HORNSUNDSUPERGOUP

BONSOW LAND SUPERGROUP

S ~ R I ~ P P L A N D GROUP

BULLBREEN GROUP

Antarcticfjellet Formation Perleporten Formation

Bulltinden Formation Motala~ellaFormation

VESTGOTABREEN COMPLEX

BJORNOYA GROUP (? Vendian)

TECTONIC CONTACT COMFORTLESSBREEN & ST JONSFJORDEN GROUPS

ArkFjellet Formation Hornsundtind Formation

Sjdanovfjellet Member TsjebysjovfjelletMember Rasstupet Member Nigerbreen Formation Dusken Formation Luciapynten Formation Wiederfjellet Formation Goesbreen Member Paierbreen Member SOFIEKAMMEN GROUP Nordstetinden Formation Nordstebreen Member Hansbreen Member Slaklidalen Formation Vardepiggen Formation Flagtoppane Member Midifjellet Member Olenellusbreen Member Bl&stertoppen Formation Russepasset Member Flak~ellet Member GAsbreen Member SOFIEBOGEN GROUP G&shamna Formation

HINLOPENSTRETET SUPERGROUP OSLOBREEN GROUP Valhallfonna Formation Profilbekken Member Olenidsletta Member Kirtonryggen Formation Nordporten Member Basissletta Member

Sparreneset formation

Spora Member

Tokammane Formation

Kross~ya formation

Ditlovtoppen Member TopigganeMember Bl&serbreen Member POLARtSBREEN GROUP

Fig. 14.1. Cambrian and Ordovician rock units in contemporary nomenclature and classification. The successions are carried forward from the more detailed descriptions in the regional chapters 6, 7, 9, 10 and 11.

258

C H A P T E R 14

/12~

/9 ~

~81 o

/15~

121 o

/18 ~

/24 ~

SVALBARD CAMBRIAN ORDOVICIAN OUTCROPS

\27 ~

<3

80~

5

Sparreneset ~80 ~

9~

Profilstranda

-~-

~3 801~ ~Kross~ya ~.;i,,Olenidsletta

9.i"~VaIhaIIfonn~ '

~t

""

r

9:,~i ii,,i ,,:,,

.

.

i "l

L ,,,r : tt

9

..'o

ine

9 .

79 ~

i;'

,J-

i

89

79~

.,'

27~ o

o

a~,,D

~

~gg~---' e 9

s

~78~ ~estgo't~abree 7 8~

~

II

r'

', 9

/o

ss

9

'-;,;

r

i

9 s . m" as /

s

r ~ - -s

a . sS

I,,Ist

Wedel Jarlsb~ 77 ~

,=,

aen *"

Lar

a

77?

S

o~

Q9 Q

o

Serkapp Land -~1 2~~

7~6~ ~

Post. (

- y.

Cambrian & Ordovician

Pre-Cambrian Ymerdalen

[ e ~ ] ~ : ~ I ~v~tr•

/15 ~

/

-

~ ~IL_

Antarcticfjellet 0,

"~9or;~ II

121o

I

I

km 124 ~

I

,

100 76 -~

Fig. 14.2. Map of Svalbard showing the distribution of Cambrian and Ordovician outcrops, with place names from which the principal rock units are named.

CAMBRIAN-ORDOVICIAN HISTORY

British Graptolite Trilobite zones

Chronostratic scale Fortey et al. 1995

Baltoscandian conodont zones

259

Eastern North America

Estimated Ma '

~ .Archaeocyaths I' S1

Rhuddanian

, Lly

0 3

Hirnantian

O)

<

Rawthenian

~ Small shelly fossils

Akidograptus acuminatus G. persculptus extraordinarius pacificus Dicellograptus complexus ancepts

Soudleyan Harnagian

foliaceous Diplograptus (=multidens)

Costonian Aurelucian

03

Velftreyan

Llandeilian I

E

Abereiddian

Fennian

A. superbus

A. ivaerensis

Pygodus amserenus

alobatus g erdae

I I ] I

variabilis

t ~ I I ]-14

lindstroemi robustus reclinatus foleaceus sulcatus gracilis

E. suecilicus

D. hirundo

ozarkodefla E. vadabilifis [ flabellum M. flabellum_parvum Oriqinafis Prioniodus navis-triangulatis

Whitelandian

I

D. nitidus

443

439.5 Richmond

440.1

Maysville

440.6 443

Edenian

444.5 447.1

Sherman

449.7 450 ,457.5 463.2

Kirkfield Rockland Black River

449

464

maegalis

artus (=D. bifidus)

Isograptus g i b b e r u l u s ~

E: <

I t ~

kiekensis

Didymograptus murchisoni

01

, 9 439

Gamach

P. serra

02

Anticosti

Amorphognathus ordivicicus

Nemagraptus gracilis

Glyptograptus teretiusculus

I Bowdng I Tucker & et al. McKerro~ 1993 1995

,i

Distmodus kentuckyensis

Cautleyan Dicellograptus complanatus Pusgillian Pleurograptus linearis Streffordian Onnian Actonian Marshbookian Cheneyan Woolstonian Dicranograptus clingani Longvillian Barrellian

Harland et aL 1990

458 Chazy 486.6

,472.7 Whiterock

i

476

I

470

Cassinian

Depikodus evae

{3 Moridunian Migneintian

D. deflexus Phyllograptoides (appoximatus) sedwickii salopiensis

Prioniodus elegans

Jefferson

Paraoistodus proteus

493 Deming

Drepanoistodus deifier

tenellus Gasconadian

Cressagian 01

D. flabelliformis Dolgelly

Maentwrog

~2 431

~

"O

Menevian

a

Solvan Toyonian

Lenian

Botomian Atdabanian Aldanian Tommotian

s V2 V1

Nemakit-Daldyn Ediacara Varanger

Acercare Leptoplastus Peltina Parabolina Olenus Agnostus pisiformis Paradoxides forschammeri Paradoxides paradoxissimus Eccaparadoxides Plagiura / Pofiella Bennia / Olenellum Nevadella Holmm Fallotaspis Holmia inuistata Dokidoeyathus lenicus D. regularis Nochoroicyathus sunnaginicus Puvella cristata Anabarites trisulaticus / Sabellidites cambricusis Poundian fauna

angulatus 510

485

Croixian 514

517 Albertian

~ 505

530 536

] 518

525

i i

9 526 Waucoban

522

554

525

560

530

~

534

570

I 9 545

58O 590

545

600

,ll~r;l

~4n

Fig. 14.3. Cambrian-Ordovician chronostratic time scale divisions with biostratigraphic correlations and estimated chronometric ages. Standard timescale from Harland et al. (1990), Ordovician scale modified from Fortey et al. (1995) and the Early Cambrian scale from Zhuravlev & Wood (1996). Chronometnc ages from: (1), Harland et al. (1990); (2), Bowring et al. (1993); (3), Tucker & McKerrow (1995). Dots represent tie points from Harland et al.

260

14.1

CHAPTER 14

Cambrian-Ordovician time scale

Available faunas afford good correlation with the global time scale and some isotopic ages are also clearly Ordovician or ?Early Cambrian. It is therefore doubly relevant to consider the best estimates of numerical calibration of the chronostratigraphic scale. In the last few years there have been radical and relatively precise revisions of the Cambrian time scale so that the Early Cambrian sequences as shown Fig. 14.3 presents a significant advance on Cowie & Harland (1989) and Harland et al. (1990). New references justifying the numerical values are given in the caption. The Cambrian chronostratic scale has also been refined, especially the Early Cambrian Epoch, where the divisions and their nomenclature and beginning to settle from investigations in eastern Canada and northern Siberia. The Tommotian stage previously widely regarded as the initial Cambrian interval is now generally agreed to be preceded by a longish interval also characterized by small shelly fossils. This interval has been variously refined as Rovnian, Kotlinian and Manychaian in Siberia, and Etcheminian in Newfoundland; but now American-Russian cooperative investigations have settled on the old name Nemakit-Daldyn. The five stages of Early Cambrian are combined here under the appropriate name Siberian so that we may apply two earlier names to convenient pairs thus: Toyonian + Botomian for late Siberian; Aldanian=Atdabanian +Tommotian, for middle Siberian and the long Early Siberian is the Nemakit-Daldyn. This usage accords with McKerrow et al. (1992). The result is that Early Cambrian divisions now amount to the greater part of Cambrian duration, altogether much reduced from some early estimates. Thus it is not so surprising that so much Cambrian rock turns out to be Early Cambrian. The Ordovician chronostratic scale appears to have been stable for many years, based largely on the Welsh successions. However one revision appears to be necessary in the light of international correlation. The timehonoured Llandeilo division, often characterized by Nemagraptus gracilis as well as Glyptograptus teretiusculus appears to be represented partly in the Llanvirn and partly in the Caradoc as a result of more rigorous studies of type sections (e.g. Fortey et al. 1995). That new scale is incorporated in Fig. 14.3. Nevertheless that proposal is not without detractors (Basset & Owens 1996). New understanding of the extended time scale of earliest Cambrian (Early Siberian) events has led to the realization that the Cambrian record in Svalbard, and indeed in other places, begins with identifiable BonniaHolmia faunas. Thus at least the earlier part of Early Cambrian (Siberian) history (Nemakit Daldyn, Tommotian, Atdabanian and even Early Botomian) is not documented. A eustatic explanation for the widespread Cambrian transgression is certainly relevant. Moreover, the sporadic poor earlier fossil record may, in part, be attributed to anoxia (Zhuravlev & Wood 1996). Anoxia is not argued for Svalbard at this time, but it suggests that 'unfossiliferous' Early Cambrian strata may either not have been recognized or have been confused with Vendian deposits.

14.2

Cambrian-Ordovician biotas and correlation

Apart from occasional stromatolites, oncolites and Girvanella, which seem to occur throughout the stratigraphic column in appropriate facies and which have not been systematically described nor given any chronostratigraphic significance, we have rich faunas of trilobites and nautiloids, also gastropods and brachiopods with rare sponges and an outcrop rich in graptolites and increasingly evident conodont faunas. The outcrops occur in four distinct areas: (i) Bjornoya, (ii) south Spitsbergen (Wedel Jarlsberg Land & Sorkapp Land), (iii) northeast Svalbard (Ny Friesland, centre and northeastern, and the opposite shore in Nordaustlandet) and probably (iv) Oscar II Land in the centre west of Spitsbergen.

14.2.1

Bjornoya

The first connected account of Bjornoya was by Horn & Orvin (1928). The Ymerdalen Formation (of Krasil'shchikov & Livshits 1974), overlies unconformably the Sorhamna Formation of

probable Vendian age and comprises, Holtedahl's (1920) two units: the Younger Dolomite overlain by the Tetradium Limestone. Further work (Armstrong & Smith in press) renamed these units as Perleporten and Antarcticfjellet formations respectively within the Ymerdalen Group. The Perleporten Formation with Calathium, Archaeoscyphia and Piloceras was argued to be (Ozarkian) Canadian age. The Antarcticfjellet Formation, yielded a rich fauna, 120m up from the base, which Holtedahl correlated with the Boreal Black River rocks of the USA correlated above as early Caradoc (Costonian). This included: Tetradium cf. syringoporoides Ulrich; several bryozoan species; crinoid stems; Rafinisquina sp.; Maclurites sp.; Orthoceras (Kionoceras?) sp.; Endoceras (Vaginoceras?) sp.; Actinoceras bigsbyi Bronn. ? = A . Tenuifilum Hall; Gonioceras (occidentale Hall?.) sp.; Gonioceras nathorsti. New conodont investigations (Armstrong & Smith in press) added significantly to the correlation potential. The Perleporten Formation, between 250 and 400m thick, yielded identifiable conodonts, only at 60 m from the top of the underlying dolomitic sequence, with Paraprioniodus costatus (Mound) and new Genus 4 of Ethington & Clark (1982) indicating latest Early-Mid-Whiterockian, i.e. probably Abereiddian (Early Llanvirn). The main body of the formation could be, as Holtedahl estimated, of late Canadian (Arenig age). The overlying Antarcticfjellet Formation was altogether more productive, beginning with a sample, only 1.5 m above its base, with Appalachignathus delicatulus, Phragmodus sp., Drepanoistodus suberectus, and new species of Oulodus, Panderodus, Plectodina and Culumbodina and two species referred to a new genus. At 13m up Trigonodus? appeared; at 57.85m Eraticodon balticus Dzik, and Panderosus feulneri (Glenister), and at 77 m another new Oulodus species and Dapsilodus. Appalachignathus delicatulus and E. balticus together confirm White Rock to Black River age. More precisely, however, the fauna matches closely part of the eastern North Greenland sequence which promises to provide a new conodont standard. The conclusion of the discussion of correlation by Armstrong & Smith is that the base of the Antarcticfjellet Formation is earliest Black River and the youngest dark horizon is mid-Black River or mid inaequalis to gerdae zone, i.e. Early Caradoc. Moreover, the close affinity of the Ymerdalen conodonts to those of eastern North Greenland suggested to Armstrong & Smith a close proximity to be discussed further in Section 14.5.1 below.

14.2.2

South Spitsbergen Cambrian and Ordovician faunas

Although suspected by A. K. Orvin in south Spitsbergen, the first well-defined Spitsbergen Cambrian and Ordovician faunas were described by Major & Winsnes (1955) from Sorkapp Land. Their results have been generally used and not significantly modified since then (Fig. 14.4). Major & Winsnes (pp. 27-28) summarized, their stratigraphic conclusions thus: Arkfjellet Series (no fossils), ?Early Ordovician or younger Sjdanovfjellet Series, Beekmantown fauna, Early Ordovician Gr~tkallen Series (no fossils recorded) Slakli Series, Early Cambrian fauna G~shamna phyllite (no fossils), Lower Cambrian or Eo-Cambrian. (tectonic break equivalent to conglomerates or tillites north of Hornsund-W.B.H.) H6ferpynten Series (equivalent to Older Dolomites of Bjornoya, Murchison Bay strata of Nordaustlandet, and Eleonore Bay Formation of East Greenland). Birkenmajer's work began north of Hornsund in 1957 and in 1958 was extended to the south. The first results (1958) recorded inarticulate brachiopods at Nordstetinden 'probably of Cambrian age' and a rich and well-preserved Early Cambrian (Georgian) tribolite fauna at Vardepiggen, Nordstetinden and Kamkrona. He introduced the names Sofiekammen Formation for the lower strata (including the Cambrian faunas) and Sorkapp Land

CAMBRIAN-ORDOVICIAN HISTORY BJORNOYA

TIMESCALE

S1

Llandove~ Rhuddanian

03 Ashgill -~ m

Caradoc

Hir Raw Can Pus Str Che Bur Aur

~5 O

LIn

I

(?Arkfjellet)

I I

Hornsundtind , Sjdanovfjellet Tsjebysjovfjellet * Rasstupet

I I I I

, Nigerbreen (Hornstullodden sequence) ?Dusken ?Luciapynten ?Wiederfjellet

I

Mig

I I I I

Dolgelly Merioneth "s

Car

I

Perleporten

Cre

O1

I I

Maentwrog

Nordstetinden (Gr&kallen sequence)

I

I

St Davids "~2

NORDAUSTLANDET

I I

Mor Tremadoc

?Barents

NY FRIESLAND & OLAV V LAND

Antarcticfjellet

Fen Whi

Arenig

Bulltinden Sar~oyra

SORKAPP LAND & EASTERN WEDEL JARLSBERG LAND

Ash

Llanvirn

02

PRINS KARLS FORLAND

Aavatsmarkbreen (Grampian Gp) Kaffioyra Pinkie * Motalafjella

Llandeilian Abereiddian

OSCAR II LAND

261

Menevian

I I

Solvan

I

Valhallfonna Fm. , Profilbekken * Olenidsletta Kirtonryggen Fm. (Nordporten) * Basissletta

Sparreneset

(Spora)

Arg

Tre

-e 3 Upper Ditlovtoppen

-6;2

?Gn~lberget

I

Toyonian ~-

I I I

Botomian

I

Atdabanian

* Slaklidalen

Lower Ditlovtoppen

by

Krossoya Bot

Topiggane

I

.t--

co

Slakli A

[ Vardepiggen [ a u n a s T . . _ t I.~.~ B ske. ito..9..p~en .

Nb

r Bl~revbreen

I I

Tommotian

~m

I I

-~1

Nemakit-Daldyn

I

V2 V1

Nk-D

I

Ediacara

I

Varanger

Lovliebreen protolith

?~ Sorhamna

Scotia Group

V2 II~V~

Fig. 14.4. Cambrian Ordovician tentative correlation chart for Svalbard formations. See Section 14.2.6. *Fossiliferons horizons. Formation for the upper strata (including the Ordovician faunas). For the International Geological Congress in 1960 Birkenmajer offered a scheme unifying the results to date from north and south of Hornsund (Fig. 14.4). He offerred the same scheme further modified by changes in rank (Birkenmajer 1975a, b). Birkenmajer (1978a, b) defined in some detail all his proposed lithostratigraphic units and illustrated by sketches their occurrence in the complex mountain structures. However, this work does not follow him in assuming that the groups (Sofiekammen and Sorkapp Land) are precisely Cambrian and Ordovician respectively, because the upper formations of the lower group and the lower ones of the Sorkapp Land Group have yet to yield chronostratically useful fossils. Therefore Major & Winsnes' 'Series' names for this discussion of faunas are retained.

Slakli faunas. At least four fossiliferous horizons have been noted (marked by asterisks in Fig. 14.4). The Slaklidalen (limestone) Formation is said by Birkenmajer to correspond to the Slakli Limestone of Major & Winsnes (1955). There is, however, some uncertainty because Major & Winsnes described: (3) black shale (2) light solid quartzite bed and (1) fossiliferous sandy limestone with intraformational conglomerates Birkenmajer (1960d), however, placed (2) & (3) below (1).

Major & Winsnes described the fauna from localities at Midifjellet and Wiederfjellet as follows: pteropods Hyolithellus cf. micans, Billings Hyolithus sp. gastropod Platyceras primaevum, Billings brachiopod Obolella cf. atlantica, Walcott (see Cowie 1974) trilobites Olenellus cf. thompsoni, Hall (and two or more other species); Serrodiscus bellimarginatus (Shaler & Foerste); S. cf. speciosus (Ford); Calodiscus agnostoides (Kobayashi); Pagetia sp. All the above were matched with Appalachian forms and Hyolithellus with Scotland, Shropshire, East Greenland and western Norway; 'there is therefore no doubt that [they] are of upper Early Cambrian age (Georgian Epoch)' (Major & Winsnes 1955, p. 25). Moreover, the fauna in East Greenland has no species in common with Spitsbergen except for Hyolithes. It suggested to Winsnes a mixed fauna connecting the Olenellus-Callavia sea. and the Redlichia sea. Cowie (1974), however, in reviewing these data, and in a climate favouring plate-tectonics, noted that the Bl~stertoppen Dolomite had yielded species of Olenellus (to be described later, Birkenmajer

262

CHAPTER 14

& Orlowskie 1977). He further noted that Birkenmajer's Olenellus shales (Olenellusbreen Mbr) were characterised by Olenellus svalbardensis (Keilan 1960), but did not concur with the identification of the other find, Nevadella, which specimen he regarded as 'olenellid indet'. The new species (O. svalbardensis), until found elsewhere, helps little with correlation and therefore Cowie (1974) referred the original Slakli faunas to the Pacific Province, but with some Atlantic affinities (because of Serodiscus and Callodiscus). 'The tribolites including the eodiscoids and olenellids indicate the upper part of the Early Cambrian (?Bonnia-Olenellus Zone of Fritz 1972), but the fauna probably does not indicate the youngest part of lower Cambrian times'. The olenellid fauna, found in 1970 from low in the Bl~tstertoppen Fm, led Birkenmajer & Orlowski (1977) to the division of the formation into three members. The 5 m shale, with tribolite-bearing concretions, occurs at the base of the Flakfjellet Mbr 35.5 m above the G{tshamna phyllite. Olenellus svalbardensis Kielen and the new species O. Sculptilis were described. Anemone burrows Dolopichnus sp. were also recorded. In conclusion, Cowie's assessment was not modified by these finds and it may be taken as applying to the whole Slakli fauna which extends downwards to near the base of the Blfistertoppen Fm.

Gr~kallen sequence (GnAlberget to Dusken formations). Within the GnSlberget-Dusken sequence the Nordstebreen Mbr of the Nordstetinden Formation yielded poorly preserved inarticulate brachiopods including Lingulellaferruginea (Salter), which could be of any Cambrian age (or even Ordovician). The Luciapynten Dolostone Formation has sponge-like stromatolite structures and vermicular dolostone bands suggestive of bioturbation.

Sjdanovfjellet faunas. The Nigerbreen Lst (Fm) with vermicular bioturbated structure and chert lenses was reported by Major & Winsnes (1955) to contain gastropods: Ceratopea sp., Maclurea sp., and nautiloid Vaginoceras cf. longissimum (Hall), which they correlated with the Beekmantown Group in North America. The Rasstupet Lst (Mbr) with fossiliferous limestone described by Major & Winsnes (1955) contained: gastropod: Maclurea sp.; brachiopod: Diaphelasma cf. breviseptatum Ulrich & Cooper; sponge: Recaptuculites sp.; nautiloids: Proto~Tcloceras cf. lamarcki(Billings); P. cf. arkansasense, Ulrich, Foerste & Miller; Voginoceras cf. longissimum (Hall); actinoceratid. The overlying Tsebysjovfjellet Limestone yielded to Major & Winsnes: gastropods:

nautiloids:

Hormotoma sp. Maclurea sp. Straparollina aft holtedahli Strand Oneotocerasloculosum (Hall) Beekmanoceras priscum (Ruedemann). Bathmanoceras aft tennessense Ulrich et al. Polygrarnmoceras sp.

The nautiloids, in particular were described and interpreted by Major & W i s n e s (1955). All match North American Early Ordovician faunas. The Protocycloceras (three species), Oneotoceras (two species), Beekrnanoceras, Bathmoceras and Cassinoceras are all typically Canadian, the last named being restricted to Late Canadian and occurs also in Bjornoya, whereas Oneotoceras may be of Early Canadian age. The Vaginoceras was suggested by Major to be younger than Canadian but, if Birkenmajer's (1978b) identification of strata is correct, it was found in the lower of their fossiliferous units. Protocycloceras occurrences extend to the Appalachians and Newfoundland, the Younger Dolomite in Bjornoya and also from Greenland.

The Arkfjellet Formation. The Arkfjellet Formation comprises slates, with a limestone conglomerate in the middle, and in which only indeterminate fossils were found.

14.2.3

Northeastern Svalbard

The northeastern sector of Svalbard is the third area with CambroOrdovician outcrops. All belong to the Hecla Hoek sequence and fossils were found in three main outcrops as follows: Nordaustlandet, central Ny Friesland and northeastern Ny Friesland. The first paleontological evidence from the Hecla Hoek sequence was de Geer's observation in Nordaustlandet of worm tracks in the dolostone of Krossoya, Murchisonfjorden, (De Geer 1901). Following this discovery Kulling (1934, p. 188-190) described this Cape Sparre Formation of which the upper-most unit (our Sparreneset Formation) is a horizon of dolomitic mudstone exposed on the extreme southwest (shore) of Sparreneset in the core of a synclinal fold. The first body-fossils recorded were inarticulate brachiopods Lingulella and Obolus and the previously observed trail marks (fucoids) were referred to Helminthoidichnites. Lauritzen & Yochelson (1982) reported and described Salterella rugosa from Krossoya in westernmost Murchisonfjorden. They discussed its relationship to Volborthella Schmidt also occurring in northeast Svalbard and possibly congeneric.

Ny Friesland. In Central Ny Friesland in 1953 a Cambridge party found the first recorded Hecla Hoek fossils which were identified as Salterella rugosa Billings. This Early Cambrian age confirmed the underlying Hecla Hoek succession as Precambrian (Harland & Wilson 1956; Hallam 1958). Further work on the Oslobreen Group yielded inarticulate brachiopods and Early Ordovician faunas (Gobbett & Wilson 1960), in the collecting of which C.J.B. Kirton lost his life on the mountain named for him, and hence the Kirtonryggen Formation. The Salterella material was re-examined by Lauritzen & Yochelson who failed to note the record. The nomenclature of this succession has been revised more than once (see Chapter 7) and the essentials of the Cambro-Ordovician strata comprising the Oslobreen Group are shown in Fig. 14.4. The lower part of the sequence which thins to the northeast is best exposed in central Ny Friesland. In Northeastern Ny Friesland in 1965 a new Ordovician fauna was discovered by a Cambridge party and was collected systematically in 1967 (Vallance & Fortey 1968; Whittington 1968). This was on the shores of Hinlopenstretet, 10km across the strait from the earliest finds at Sparreneset. The fauna from the upper part of the succession proved to be so rich that a joint study was continued from the British Museum (Natural History), and the Paleontologisk Museum, Oslo (Fortey & Bruton 1973). Work on the fauna had generated at least 25 specialist papers (listed by Harland et al. 1992). The faunas are now outlined formation by formation. Tokammane Formation. In the Oslobreen series of Harland & Wilson (1956) and Gobbett & Wilson (1960) three lower divisions were described beginning with the Oslobreen Sandstones and followed by two divisions of the Oslobreen Dolomites. These Three divisions made the essential Cambrian unit named the Tokommane Formation by Harland et al. (1966). Swett (1981), working principally on this lower unit divided it into a lower Bfftrevbreen (sandstone) Member and an upper Topiggane (shale) Member but combined the dolostones units into one Ditlovtoppen (dolomite) Member.

Blhrevbreen Member, 19.8m. Gobbett & Wilson (1960) noted that, interbedded with the (Oslobreen) sandstones, are siltstones with 'fucoid' markings and some tubes resembling Monocraterion tentaculatum Torrell (Westerg~rd 1931). Swett (1981) from this lowest member reported abundant trace fossils: Diplocraterion, Monocraterion, Scolithus and Planolites.

C A M B R I A N - O R D O V I C I A N HISTORY

Topiggane (shale) Member 22.3 m. This was distinguished by Swett because of its interesting glauconitic, phosphatic potash and dolomitic facies. No faunal information is available. It is not clear whether this Topiggane Member includes Gobbett & Wilson's Bed 1, a unique dolomitic shale, of the succeeding dolomite member. Recorded thicknesses and lack of mention of Salterella in it would exclude it. Swett did not relate his work closely to the sections reported by Gobbett & Wilson. Ditlovtoppen (dolostone) Member, (lower division 65 m). Gobbett & Wilson described beds 1 to 6 with occurrences of Salterella in beds 1, 3 and 6. These were identified originally as S. rugosa. Fritz & Yochelson (1988) prefered S. macculochi, and from their North American occurrences concluded that Salterella is a good index fossil for mid Bonnia~Olenellus age. Bed 1 is a dolomitic shale which may be the Topiggane Shale of Swett. Ditlovtoppen (dolostone) Member (upper division, 140 m). Gobbett & Wilson logged 31 beds recording Obolus (and Lingulella) in beds 10, 14, 20, 22 and 24. However there is no complete section. Hallam (1958) noted Obolusfrom the material collected. Swett (from another section) recorded a rich Salterella bed 120m above the Topiggane shale and Planolites at 131m. He recorded the top (of the formation) at 264 m with a distinct change to dolostone. The Tokammane Formation is thinner and less well exposed in northeastern Svalbard. Fortey and Bruton (1973) recorded Monocraterion Torell, and Diplocraterion from the lower sandstones (Bl~revbreen Mbr). The following gap of 25 m probably corresponds to the Topiggane Shale. The Ditlovtoppen Dolostone Mbr exhibits dolomitised vermiform and tubular patterns. An olenellid cephalon and other fragments were found in a glauconitic facies, 32m up in the member. Further up the succession are fragments of inarticulate brachiopods. The top 30 m appears to be barren. A Late Early Cambrian (?Botomian-Toyonian) age was concluded for the Tokammane Formation. The whole fauna indicates a late Early Cambrian age equivalent to the North American Bonni&Olenellus zone of Fritz (1972). Kirtonryggen Formation Lower Kirtonryggen Formation. The base of the formation is marked by a sharp change from dolostone to limestone which forms the 'Lower Oslobreen Limestone' (Member) and in a flaggy facies (bed 3 about 70 in up) the following were recorded (Hallam 1958, Gobbett & Wilson 1960). Lecanospira spp., Ellesmoceratidae gen. and spp. Maclurites sp, Macluritella? sp. nov Eoorthis? multicostata Poulsen; Hystricurus wilsoni (Gobbett 1960) also cystid plates, and a solitary rugose coral. Swett (1981), noted that Early Ordovician conodonts occur 160 m above the Ditlovtoppen Formation. In the northeast the equivalent but much thinner Spora Member contained trilobites, Leiostegium, Hystricurus, and Symphysurina; brachiopod, Syntrophina; gastropod Ophileta; and Ellesmeroceratid nautiloids. This fauna indicates an early Canadian age (zones B through D of Ross 1951). Middle Kirtonryggen Formation. The following 70m of dolostones, porcellanous and oolitic, exhibit only stromatolites. This 'Middle Oslobreen Limestone' comprises 200m of grey-brown cherty limestones. Algal nodules, and Girvanella occur. 'Knobbly' flags with trace fossils and stromatolites also yielded the following (Gobbett & Wilson 1960, p. 451). Helicotoma sp., aft. Horrnatoma sp. nov., Archaeorthis cf. groenlandica Poulsen, Bolbocephalus cf. seelyi (Whitfield), Bolbocephalus sp. nov. Bathyurellus sp. nov. Bathyurellus cf. tenuis Poulsen, Hystricurus sp. This unit approximates closely to the Basissletta Mbr cf. the northeast of varied lithology. Fortey & Bruton (1973) referred the stromatolites to Cryptozoa and Collenia types. Ooliths and oncolites are often silicified. Edgewise conglomerates are characteristic. Only Hystricurinae and Bathyurellinae were recorded from the limestones. In all a middle to Late Canadian age is indicated. Upper Kirtonryggen Formation. The upper part of the formation in central Ny Friesland is of uniform massive limestones with partial dolomitization and red hematite staining. The following few fossils were recorded from only the lower 300 m. Maclurites sp.; ?Hormotoma sp.; Straparollina aft. holtedahli Strand; ?Piloceratidae gen. et sp. nov.; cf. Protocycloceras Hyatt. The Nordporten Member in the northeast is probably equivalent to the lower part of the upper Kirtonryggen formation to the south. Trilobites, brachiopods, nautiloids, gastropods and ostracodes are abundant throughout the member and include (Fortey & Bruton 1973):

263

Trilobites: Bathyrellus abruptus Billings; B. cf. marginatus Billings; Bathyurina cf. timon Billings; Petigurus groenlandicus Poulsen; Bolbocephalus spp.; Uromystrum sp.; Benthamaspis cf. problematica Poulsen; Oculomaqnus sp.; Licnocephala sp.; Ischyrotoma sp.; Strigigenalis sp; Ptyocephalus sp.; Illaenus sp.; Pilekia sp.; Parahystricurus. Nantiloids: Tarphyceras, Piloceras, Arkoceras spp The assemblage is of Late Canadian age. Valhallfonna F o r m a t i o n . This u p p e r m o s t u n i t o f the w h o l e Hecla H o e k is u n i q u e to n o r t h e a s t S v a l b a r d a n d a n y h i g h e r strata w o u l d be c o v e r e d by the sea. The lower Olenidsletta Member is of black (cf. underlying grey) limestones (stinkstone). It is distinguished by abundant poorly preserved graptolites. A characteristic assemblage of trilobites in the lower 75 m is dominated by Olenidae species mostly new, but including Tropidophina, Triarthrus, Plicatolina, Micragnostus aft. Telephina and Carolinites genacinaca Ross. Abundant graptolites include: Dichograptus octobrachiatus (Hall), Tetragraptus quadribrachiatus (Hall), T. amii Lapworth, T. serra (Brogniart), T. fruticosus (Hall), Didymigraptus extensus (Hall), Phyllograptus typus Hall, P. ilicifolius Hall, Goniograptus thureaui (McCoy), Temnograptus sp. and Loganograptus sp. This assemblage has wide affinity and corresponds with the early Arenig, deflexus zone (Fortey & Bruton 1973). The next 27 m is characterized by large asaphids (Niobe, Megalaspides and aft. Ogygiocaris). Olenids, except Triarthrus, are rare. Ampyx and Nileus are abundant, Shumardia, Eorobergia, Lacorsalina and Mendolaspis also occur with inarticulate brachiopods. The age is Arenig. The upper 43 m has extensiform Didymograptus (Fortey 1971) and a late Arenig age is suggested, hirundo or Isograptus zone (Fortey & Bruton). Profilbekken Member consists of more varied and massive limestones in contrast to the underlying black flags. The lower part is rich in nileid and cybelinid trilobites. The next 40m has numerous Peraspis and Shumardia, large orthoconic nautiloids, and large monaxon sponge spicules (Hyalostella type). Many of the sediments were bioturbated. The final 35 m is of massive limestone with echinoderm fragments, and the uppermost bed of all (in a tight syncline) is grey-green shale. The fauna is extremely rich (Fortey & Bruton 1973, p. 2235). Trilobites are mainly of new species of Bathyuridae, Nileidae, Raphiophoridae, Remopleuridae, Pliomeridae, Cheiruridae, Illaenidae, Harpidae, Scutellidae, Shumardiidae, Encrinuridae, Dimeropygiidae and, Komaspididae. Brachiopods include Skemidioides, Orthidiella, 'Camarella', Lingulops and Scaphelasma. This fauna compares closely with the Table Head Formation of Newfoundland - typical White Rock stage, i.e. early Mid-Ordovician. The Arenig-Llanvirn boundary is thought to lie within this member. The uppermost graptolites (Tetragraptus cf. hemirotundus and Glyptograptus dentatus suggest an early Llanvirn age. The above faunas are listed only from preliminary accounts of material that has continued to be worked on and in which tribolites were given priority treatment. This detail is given, not only because of the importance of this sequence in Svalbard, but it is one of the richest biotas of Tremadoc, Arenig, and Llanvirn ages anywhere.

Nordaustlandet. The Sparreneset and Krossoya units. O f the inarticulate b r a c h i o p o d f a u n a f r o m a very small e x p o s u r e n e a r to sea level at Sparreneset, little can be said. It w a s t r a d i t i o n a l l y d a t e d as Early C a m b r i a n . This general o p i n i o n was s u p p o r t e d by the discovery o f Salterella rugosa in the a n a l o g o u s u n i t o n K r o s s o y a w h e r e olenellid trilobites were also r e p o r t e d . In these islands the thickness o f the succession m a y a m o u n t to 8 0 0 m a n d an Early O r d o v i c i a n f a u n a was also r e p o r t e d in small islands to the N W o f K r o s s o y a by L a u r i t z e n & Y o c h e l s o n (1982). H a r l a n d in 1974 n o t e d a fault in the sequence at S p a r r e n e s e t a n d suggested a lithological similarity o f s o m e o f the beds to the N o r d p o r t e n M e m b e r . T h e r e c o u l d be tectonic j u x t a p o s i t i o n o f C a m b r i a n a n d O r d o v i c i a n strata. This s u g g e s t i o n was also c o n f i r m e d by the discoveries r e p o r t e d by L a u r i t z e n & Y o c h e l s e n (1982). This w o r k p r o v i s i o n a l l y distinguishes the well-established C a m b r i a n strata as the K r o s s o y a u n i t a n d the likely O r d o v i c i a n strata as the S p a r r e n e s e t unit. T h e s e discoveries reinforce the similarity o f coeval facies a n d p r e s u m e d original j u x t a p o s i t i o n o f N y F r i e s l a n d a n d N o r d a u s t l a n det. Salterella is also f o u n d in E a s t G r e e n l a n d , b u t has yet to be r e c o r d e d f r o m the i n t e r v e n i n g successions in s o u t h Spitsbergen.

264 14.2.4

CHAPTER 14 Oscar II Land

The first reported post-Vendian/pre-Carboniferous fossils known from the western outcrops were found at Motalafjella south of St Jonsfjorden by a Cambridge party in 1968 and, from further collections in 1969 and 1971, a fauna of corals (rugose and tabulate), gastropods, orthocones, brachiopods and echinoid spines, a Llandovery to Wenlock age was suggested (Scrutton, Horsfield & Harland 1976). The fossils were from a limestone olistostrome, slumped into the upper Bulltinden Conglomerate Member. Ohta, Hirajima & Hiroi (1986) added pentamerid brachiopods, trilobites, chain corals and crinoid ossicles confirming a Silurian age. Subsequently the Norsk Polarinstitutt collected for conodont study. This suggested an age from Late Ordovician to Silurian for the Bulltinden Formation. The older Motalafjella Formation sandstone and shale members were not productive whereas the (lower) limestone member yielded the best, yet a poor, conodont faunule, possibly ranging from Arenig through Caradoc. It is possible that the lower part of the limestone is Arenig and the upper part Caradoc in age; but a Caradoc age seems the more likely and, probably confirmed by Maclurites a mid- to late Ordovician gastropod collected just above the basal unconformity of the limestone (Armstrong, Nakrem & Ohta 1986). The rocks have been deformed and fossils are not well preserved so that few determinations have been confidently given. The likely conclusion is that the Bulltinden Formation is certainly Llandovery and possibly older and/or younger. While the Motalafjella Formation is of Caradoc age, again with a possible extended range either way. Both belong to the Bullbreen Group (Chapter 9.4.1) North of St Jonsfjorden in the hills east of Sarsoyra, carbonates named the Sarsoyra Formation contain a conglomerate and in one of the clasts Horsfield noted a rugose coral. This was reported by Scrutton et al. The fossil was indeterminate and could have been Ordovician. Later a Carboniferous age was suggested as being more likely. However, as appears below, the first thoughts were correct. An important development, already noted in Chapter 10 (Ohta et al. 1995) is the occurrence of both the high-pressure facies of the Vestg6tabreen Complex and slices of the Ordovician-Silurian strata extend north of St Jonsfjorden as far as Sarsoyra. The Sarsoyra Formation mentioned above yielded (to them) Ordovician? conodonts. The Aavatsmarkbreen Formation which was suggested as Late Vendian by Harland et al. (1993) is correlated by Ohta et al. (1995) with the (Kaffioyra) complex. This is accepted here as probably Ordovician.

14.2.5

Prins Karls Forland

The Pinkie Formation with tectonic contacts, hitherto treated as a poor analogue of the Vestg6tabreen Complex, must now be confirmed as a probable slice of the complex emplaced during the same dextral Paleogene tectonism. However, a distinction is made between the metamorphosed basic rock most probably derived from the underlying Lovliebreen Formation volcanics, taken here as Early Varanger; the deep metamorphism forming the ?subducted Vetg6tabreen and ?Pinkie rocks probably in Ordovician time and the (dextral) shearing of these rocks probably in the Paleogene West Spitsbergen Orogen. 14.2.6

Correlation within Svalbard

Tentative correlations are plotted in Fig. 14.4. The Bjornoya rocks were the first Early Paleozoic records in Svalbard and the early age determinations still stand. The largest outcrop area is north and south of Hornsund (eastern Wedel Jarlsberg Land and Sorkapp Land respectively). The outcrops span the interval from the Bonnia-Holmia Early

Cambrian (late Botomian-early Toyonian) age to Arenig but much of the intervening rock is poorly dated. The Arkfjellet strata are enigmatic; their stratigraphic relationships are not clear. They could be mid- or late Ordovician. The Ny Friesland-Olav V Land, successions are exceptionally rich in Arenig to Llanvirn faunas, not represented elsewhere in Svalbard. The rather poor Early Cambrian faunas beginning with Salterella do not readily correlate with the Slakli faunas of Sorkapp land. The tiny outcrop at Sparreneset was the second in Svalbard to yield Early Paleozoic fossils and correlation of the two units together with the Krossoya unit is now good. The Western Terranes of Spitsbergen contain newly appreciated Ordovician occurrences in Oscar II Land and in Prins Karls Forland between the Ediacara Scotia Group and the ?Silurian lithological correlation of the Barents Formation in the Grampian Group. The thick succession of the Grampian Group could be in part Cambrian or Ordovician; but no fossils have been recorded. These distinctive close associations of high pressure metamorphics and late Ordovician-Silurian fossiliferous strata are characteristic of the northern segment of the Western Terranes; the southern segment exposed earlier strata. The origin of the basic facies of the high grade metamorphics is probably in the (Lovliebreen) basic volcanics in the St Jonsfjorden Group. Ohta et al. agreed, but preferred a Middle Proterozoic age and also related the compositions with the Asbestodden basic volcanics in the Chamberlindalen Formation, which are interpreted here as coeval with the Lovliebreen basites but have no other Ordovician connexion. D. H. Collins (pers. comm.) suggested that the Early Ordovician nautiloids of the Kirtonryggen Formation are older than those described by Major & Winsnes (1955) in Sorkapp Land.

14.3 14.3.1

Cambrian-Ordovician sedimentary environments Dominant lithologies

(a) After the initial sandstone deposition almost the whole of the successions are of carbonate facies: limestones (often oolitic, oncolitic, stromatolitic) with ubiquitous dolostones many of which are the result of dolomitization. Silicification of fossils and bands of chert are also characteristic. In the northeastern Hecla Hock sequences intraformational breccias and other indications of shallow water conditions are especially common. Shaly and black (bituminous) facies, often more fossiliferous, would appear to reflect deeper water environments (e.g. the graptolite-bearing Valhallfonna Formation). (b) On the other hand in the west, in Oscar II Land, more mobile facies are evident with massive Bulltinden conglomerate and its olistostromes suggesting slumping off the edge of a carbonate platform. (c) In Prins Karls Forland possibly coeval rocks suggest rapid siliciclastic deposition with thick turbiditic facies. The supposed Early Paleozoic (probably Late Ordovician-Silurian) Grampian Group totals 2730m.

14.3.2

Distinctive Early Cambrian facies

The potash horizon. A peculiar and distinctive facies is found in the Early Cambrian sequence in Ny Friesland where the strata were distinguished as the Topiggane Shale Member (Swett 1981). Grey, and some greenish shales, are interbedded with thin, brownishweathering, glauconitic, phosphatic and dolomitic sandstones. Their distinctive feature is the anomalously high potash concentration, occurring in finely crystalline authigenic K-feldspar (adularia). This phenomenon has been reported from coeval strata in western Newfoundland, Scotland and central East Greenland. To account for the required potassium rich waters Swett ruled out a volcanic source because the whole Cambro-Ordovician successions lacks a volcanic component. He suggested, rather, that the

CAMBRIAN-ORDOVICIAN HISTORY dolomitization, so noticeable in these successions, released the required potassium that was then concentrated in shaly facies. This explanation was preferred to Swett's suggestion of more general weathering of cratonic sources.

Phosphate horizons. Low in the B1Arevbreen (sandstone) Member and in the middle of the Topiggane (shale) Member, Kidder & Swett (1989) described horizons of phosphate nodules. Six phosphorite localities were recorded. They are associated with the oldest remains of shelly fossils in Spitsbergen and appear to be reworked at minor disconformities, which may represent non sequences in the acritarch sequence. The centres of the concretions are enriched in P205 and CaO and are depleted in A1203, SiO2 and K20. Their origin could simply result from the shelly fossils as are common in Early Cambrian horizons elsewhere. The suggestion of oceanic upwelling is not supported here owing to the likely continental basin in which the succession occurs. Wrona (1982) reported on phosphatic microfossils from Hornsund.

14.3.3

indications of silicified evaporite minerals (Swett 1981, p.234) in Ny Friesland. In East Greenland halite pseudomorphs are abundant in the Early Cambrian succession. The chemical environment which favoured dolomitization, silicification and the reverse process of calcitization may well have been inimical to normal marine metazoan phyla. Swett did not accept a simple hypersaline explanation, but suggested a schizohaline model, with mixing of waters of meteoric and marine compositions. Against this is the wide extent of the shelf and the difficulty of accounting for occasional widespread meteoric waters being introduced throughout. In any case fossiliferous strata above and below this interval are mostly limestones and calcareous shales, the latter indicating deeper water. The inflow of salt-water rather than outflow of occasional brackish water from the shelf would be consistent with the supposed E - W alignment of Iapetus in near-equatorial latitudes. Mottled dolostones are a characteristic coloured facies occurring in most of the North Atlantic successions, Swett (1981, pp. 235 6) concluded that they were originally burrows subsequently obscured through diagenesis. He postulated a complex coeval sequence of paragenesis: (1) recrystallization, (2) dolomitization, (3) silicification, (4) calcitization, (5) dolomitization.

The Mid-Late Cambrian non-sequence 14.3.4

It has long been a problem as to why the interval of 20 or 25 million years between fossiliferous Early Cambrian and Early Ordovician strata is not represented by dateable fossiliferous strata throughout the area from western Newfoundland, northwest Scotland, central East Greenland and eastern Svalbard. In these areas carbonates of unknown age intervene. It was a time of tectonic stability with no indication of a sedimentary break, and no known unconformity. Therefore an explanation with uplift, non-sedimentation and/or erosion is unlikely. Subsidence was matched by sedimentation to retain shallow marine conditions with occasional intraformational conglomerates, ripple marks, oolites and stromatolites. There appears to have been no measurable difference in the rate of subsidence throughout Cambro-Ordovician time roughly between 0.01 to 0.02mma -1 (Fig. 14.5). Life persisted but left no body fossils useful for age estimates and it is unlikely that destruction (e.g. by dolomitization) of such fossils could have been so thorough over such a large area through, say, 10-20 million years. The facies and their distribution suggest an extensive shallow marine shelf bounding the Laurentian side of the ocean Iapetus and on which high salinity environments predominated. There are some

Subsidence rates from Cambrian-Ordovician successions in Ny Friesland Chronostratic scale

Ma

Myr

-460

02

Llanvirn

O1

Canadian

963

Merioneth

.62

St Davids

.61

Siberian

--465. 470

Thickness (m)

mm yr'

500-600

0.04-0.03

Average (mm yr )

15 -0.01

20 505

100-200

0.003-0.006

100-150

0.004-0.005

13 518 27

545

Ordovician facies in Spitsbergen

Southern Spitsbergen. Birkenmajer (1978) regarded the Luciapynten dolostone as being predominantly the result of chemical precipitation in a hypersaline basin. The sedimentary breccias indicate drying out and debris flows and slumps. The entry of the Sjdanovfjellet nautiloids suggest open sea connexions. A problem is that the highest Arkfjellet unit, dominated by shales and correlated with the Valhallfonna Formation has yet to yield diagnostic fossils. A study of the carbonate sequence in south Spitsbergen was reported in more detail by Laptas (1986). Regarding the Sorkapp Land Group (mainly if not all Ordovician) he noted that the sequence began with sandstones indicating a transgression following the Sofiekammen succession. The carbonate facies begin with the Luciapynten thick-bedded, fine arenaceous dolostones with intraformational breccias and cross-bedding. Pelmatozoans and stromatoporoids occur only at the top and are not diagnostic of age. A shallow, flat platform basin with supplies of quartz grains is suggested with concurrent dolomitization and stromatactis. The overlying Nigerbreen dark micritic limestones are characterized by thalassinoid burrows and gastropods Maclurea and Hormatoma. Towards the top, minor intercalations of synsedimentary microcrystalline dolostones increase. The gastropod opercula Ceratopea confirms a Canadian age. A restricted lowenergy, shallow shelf basin lacking terrigenous material is indicated. Micritic Hornsundtind limestones with abundant Arenig fauna occur.

5

485

V2

265

. . . . .

Ediacara

Fig. 14.5. Approximate subsidence rates for the Cambrian-Ordovican sequence in Ny Friesland. These are consistent with the regional mantle cooling rather than broad basin development. In such a rough estimate there may be one further conclusion that the rate of subsidence increases in Ordovician time in response to tectonic development related to the closure of the Iapetus Ocean. Sedimentation occurred in a shallowwater environment except for the final deepening reflected in late Llanvirn facies.

Northeastern Spitsbergen. Perhaps the most thorough investigation to date related faunal and eustatic changes especially in the Valhallfonna Formation. Webby & Laurie (1992) recognized the Kirtonryggen-Valhallfonna formations transition as a sharp reflexion of a profound flooding from rising sea level. However, incontrovertible correlations hardly arise from a close study of the succeeding biostratigraphy. It is not even clear to what extent the sea level rise is eustatic in Ny Friesland.

14.3.5

Comparison of Ny Friesland and Hornsund facies

As plotted in the correlation chart (Fig. 14.4), there is a close parallelism between the Ny Friesland and Hornsund successions. This is evident in the confirmation of Early Cambrian and Early to Mid-Ordovician ages with no positive evidence for other ages.

266

CHAPTER 14

In Ny Friesland the fold structure permits elucidation of reliable stratigraphic sequences. In the Hornsund sequence the environment was not so stable nor the facies at each horizon so uniform. The succession in the south has been suggested (Birkenmajer 1978b) as a miogeoclinal Cambro-Ordovician succession 1400m thick (cf. 950 m in Ny Friesland) on a relatively stable shelf. The Cambrian successions also begins with terrigenous, deposits (quartzites). In the south subordinate quartz conglomerates, and reworked carbonate breccias begin the succession. The quartz sand content increases from south to north. Birkenmajer suggested that a hot dry climate (with hypersalinity) could have inhibited the fauna, a control which was relaxed in the (deeper water) shales. Olenellids are preserved intact in shales and tend to be fragmented in carbonates. Regarding the Ordovician facies, Laptas (1986) concluded that the Hornsund sequence differs markedly from coeval strata of northeastern Spitsbergen and from North Greenland, and resembles sections in Arctic Canada. The similarity of such widespread facies does not, however, suggest original proximity of successions whose faunas contrast in several respects.

14.4 14.4.1

Cambrian-Ordovician tectonic environments

On the other hand there seems to be ample evidence of disturbances during Sofiekammen times, not only the Olenellusbreen conglomerate mentioned above, but others in the same member and in the Flogtoppane member. Also at Wiederfjellet Birkenmajer (1978a, fig. 15) depicted an unconformity between the Slaklidalen and Weiderfjellet formations. The most conspicuous unconformity is, however, the basis of the Hornsundian diastrophism, evident at the base of the Sorkapp Land Group where the Luciapynten dolostone rests on a pitted and even karst-like surface of the Nordstetinden (dolostone) Formation down to the Slaklidalen limestone. Indeed a regional low angle uplift increases to the south. Birkenmajer (1978) suggested that the gap between supposed Vendian and Canadian strata in Bjornoya (now 300 km to the south) is still greater. He also pointed out (1978) that the earliest Cambrian fossils have been referred to the BonniaOlenellus Zone (Cowie 1974) and that the earlier Nevadella and Fallotaspis zones are missing. The still earlier Tommotian and Nemakit-Daldyn stages are not known so that the strata in South Spitsbergen represent perhaps only a duration of c. 5 million years towards the end of the Early Cambrian Epoch, latterly reckoned at about 25 million years. The whole Cambrian period lasted perhaps 60 million years. Because the Ordovician faunas higher in the Sorkapp Land Group could begin in early Canadian time it is reasonable to guess that the instability referred to above belonged within the Cambrian Period and not demarcating it.

Northeast Spitsbergen 14.4.3

The evidence for a quite stable environment through CambroOrdovician times need not be repeated. Figure 14.5 shows rough estimates of the rates of subsidence which, even allowing for uncertainties in the time scale, averages about 0.01 m m a -1 for the whole body of strata and this is not unlike that for the preceding body of the Hecla Hoek geosyncline in which no significant break from the Planetfjella Group upwards has yet been identified (Wallis 1969; Harland 1969; Harland & Gayer 1972).

14.4.2

South Spitsbergen

According to Birkenmajer (1960b et seq.) there were two significant events: the Jarlsbergian Diastrophism between the Sofiebogen and Sofiekammen groups and the Hornsundian Diastrophism between the Sofiekammen and Sorkapp Land Group. Moreover, he equated these events with initial Cambrian and initial Ordovician boundaries. However, direct biostratigraphic constraints are lacking. All we can say with regard to their timing is that the first is pre-late Siberian (pre-Bonnia-Olenellus) and the second is probably pre-part Early Ordovician (Canadian). Regarding the structural evidence for these events the most telling is that fragments of phyllite (similar to the underlying Gfishamna phyllite) are reported in a conglomerate at the base and middle part of the Olenellusbreen Member of the Vardepiggen Formation. That is above the Olenellus-bearing Blfistertoppen Formation, for which no basal conglomerate was claimed above the alleged unconformity. Moreover, in Birkenmajer's detailed structural sketches of the various deformed contacts between the Gfishamna phyllite and the Bfftstertoppen Formation concordance is depicted. Discordance is illustrated in the stratigraphic columns. We cannot rule out a significant unconformity because the Gfishamna phyllites are more than 1.5 and possibly 2.5 km thick so that undetected overstepping may obtain. Birkenmajer (1960d) said that contacts were mostly tectonic and that the boundary may be 'discontinuity or transitional'. This is in contrast to his statement (1978) that the Jarlsbergian event was marked by folding and dynamic regional metamorphism. In support of this he (and also Birkenmajer & Orlowski 1977) quoted isotopic ages of 529-636 Ma from metamorphic rocks (presumably those west of Hansbreen) where no Cambrian rocks are known. The pre-Sofiekammen unconformity remains to be described.

Bjornoya

The hiatus between supposed (?Early) Vendian phyllites (Sorhamna Formation) and late Canadian fauna is not just a nonsequence with at least a Cambrian hiatus but a demonstrable angular unconformity.

14.4.4

Oscar II Land, Eidembreen tectonism

The Bullbreen Group, with faunas ranging from Caradoc or earlier to Llandovery or later, rests unconformably on the Vesg6tabreen (glaucophane schist) Complex (Fig. 14.6). Not only does the metamorphic grade contrast markedly with the overlying rocks, but the structures are discordant, and fragments of the schist are incorporated in the basal conglomerate (Ohta, Hiroi & Hirajima 1983; Hirajima et al. 1988). The overlying rocks are themselves folded, overturned and thrusted and their contained conodonts gave colour indications of temperatures in excess of 300~ The post-Bullbreen deformation will be considered later (Chapter 20). The age of the earlier tectogenesis of this isolated tectonic inlier has been estimated isotopically. Horsfield (1972) gave the first results from three samples, two of them by two methods; the scatter when recalculated does no more than give an Ordovician-Silurian age (including two Llanvirn ages). Dallmayer et al. (1990) reported nine determinations. Of these six (470-476Ma) confirm a Llanvirn age and four (453-459Ma) suggest a Caradoc age. Ohta (1992) added one zircon age (476 Ma Arenig Llanvirn). All data appear to be consistent with a Llanvirn-Caradoc age for the sub-unconformity complex and a Caradoc-Llandovery or Wenlock age for the sedimentary cover. A major (?Early-MidOrdovician) tectogenesis is thus demonstrable. Hirajima, Hiroi & Ohta (1984) and then Ohta, Hirajima & Hiroi (1986) reported lawsonite from the 'low-grade metabasites of the lower unit, and jadeite-quartz-albite-bearing assemblages have been identified in the high-grade cherty rocks associated with the eclogites. Thus the Vestg6tabreen Formation contains low- and high-grade rocks of the jadeite-glaucophane type metamorphic facies series'. Environments suggested by Ohta, Hirajima & Hiroi (1986) for the garnet-glaucophanite are more than 600~ and for the jadeite content of the clinopyroxenes at 14 kbar and 575~ Kanat (1984) had reported clinopyroxenes with jadeite content to reflect 10-13kbar and 300 to 450~ (Fig. 14.7).

CAMBRIAN-ORDOVICIAN HISTORY

267

Fig. 14.6. Simplifiedgeological map and representative profiles of the Motalafjella area (Oscar II Land) (after Ohta, Hiroi & Hirajima 1983).

Ohta et al. (1986) concluded that the metamorphic mineral assemblages are characterized as follows: Lower part of Lower Unit, lawsonite-glaucophane-actinolitechlorite; Upper part of Lower Unit, epidote-garnet-actinolite-chlorite, epidote-garnet, glaucophane-chlorite; Upper Unit, omphacite-garnet-glaucophane-epidote-rutile, glaucophane-phengite-paragonite and jadeite-quartz. These three progressive assemblages were compared with those of New Caledonia. A comprehensive geological map of Oscar II Land does not yet exist and there is some inconsistency in identifying the rocks referred to by Ohta (1979), Hjelle, Ohta & Winsnes (1979) & Ohta et al. (1986) on the one hand and Harland et al. (1979) on the other. South of St Jonsfjorden their calc-argillo-volcanic (CAV) formation would seem to include our Lovliebreen amygdaloidal volcanics but Ohta refers to CAV meta-diabase gabbros. The latter are possibly intrusive sills by the shore north and south of St Jonsfjorden. On the other hand his quartz-shale (Q-sh) formation is said to be volcanic. In any case, according to the interpretation here, all the volcanic rocks are intertillite and therefore in this case Early Varanger. Some dolerite intrusions would be later. Ohta identified two distinct compositions. It is agreed here that the 'diabase' rocks are post-Varanger syntectonic intrusions and are mainly tholeiitic; but, his Trollheimen volcanics are mainly Na-alkali (hawaiite) and similar to MORB but are non-oceanic in

terms of TiO2-K20-P2Os. A conclusion is therefore delayed on these data for the time being in relation to the subduction model of Ohta et al. except to infer that an Ordovician subduction zone probably existed somewhere in the region, part of which was later thrust to the surface. It was an important episode, whatever its nature, and is referred to as the Eidembreen Event (Fig. 14.8). The new discovery north of St Jonsfjorden gives a significant extension of the high pressure-low temperature facies. Ohta et al. (1995) described scattered exposures in the strandflats of Kaffioyra and Sarsoya and at Ankerfjellet as distinctive green-brown dolostone and serpentinite similar to the low-grade unit of the Motalafjella high-pressure complex. The green-brown dolostone with fuchsite is genetically related to the hydration of ultramafic rocks. These unusual coloured rocks occur in thrust zones as seen in the mountains both north and south of St Jonsfjorden and as slices in the dextral strike-slip zones in the strandflats. The occurrence of these high grade rocks thus extends 50km to the north of Motalafjella. Ohta et al. reported on the chemistry, mineralogy and paragenesis of the dolostones. Serpentinite lenses are sheared in with the magnesite dolostones, which contain ankerite-siderite and sulphide mineralizations. They may show a green colouration which is the chromium-bearing mica, fuchsite. Whereas the high grade facies are a product of Ordovician metamorphism, the tectonism that brought them to their present positions was Paleogene.

268

CHAPTER 14

MOTALAFJELLA

20

some similarity with the youngest rocks in Ny Friesland and Hornsund. At Bjornoya the record is only a little younger. These areas lie within the Caledonian realm. Peary Land through to the Queen Elizabeth Islands expose successions right through Mid- and Late Ordovician and into Silurian. But there is one important exception: the M'Clintock Orogeny recorded in Pearya by Trettin (1987, 1991) and marked by a mid-Ordovician gap and referred to in 14.5.2 below). The same appears to be the case for the Bullbreen Group with its Eidembreen Event in the western Terrane of Svalbard. These areas lie beyond the Caldeonian realm.

SJ O"

15 "C"

14.4.5

Paleozoic ages have not been determined by any method. However, lithological correlation of post-Vendian rocks suggests that the uppermost Grampian Group may be Silurian. Within its Barents Formation occurs the remarkable Sutorfjella coarse conglomerate which includes Scotia Group-type schist clasts. Whereas Harland believes that the conglomerate belongs to the Barents Formation, others have claimed it to be a downfaulted Tertiary or Devonian unit. The Barents Formation might correlate lithologically with the Holmsletfjella Formation near Motalafjella, thought to be Silurian. Whatever the age of the conglomerate,, it suggests that the metamorphism of the Scotia Group could be coeval with the preor early Caradoc (Eidembreen) event in Oscar II Land.

m 13..

10

// f

/ ARENIG / ~ ' ~ ' ~ 4~toZMa /

/

I

200

I

I

400

,i/

14.4.6

,,"

~60 Ma ~'~'--'~'~--"- 380- Ma . . . . . . 430 Ma

-" "" I

I

Prins Karls Forland

I

600

Temperature (~ Fig. 14.7. Pressure-temperature-time trajectory plot for the Motalafjella blueschist-eclogite complex. Metabasic rocks (forming the lower structural unit) within the complex are characterised by oceanic trace-element signatures, with the associated metasedimetary sequence (upper structural unit) showing evidence for deep-sea sediments (e.g. chert, metamorphosed to quartzite and marly limestone, metamorphosed to schistose marble). The lower metabasic unit contains rocks with lawsonite-pumpellyite--epidote assemblages within a generally pelitic phyllite matrix (with variable quartz content). The upper structural unit contains blocks of garnet-glaucophane schist, eclogite with schistose micaceous marble lenses in a garnetchloritoid-muscovite schist matrix. The presence of these high-pressure/lowtemperature metamorphic facies (blueschist and eclogite facies) is taken to indicate a possible subduction-related origin for the Vestg6tabreen Complex, with subduction and associated high-pressure metamorphism occurring in Early to Mid-Ordovician time (based on 4~ data). Rapid post-metamorphic uplift is inferred from the lack of retrograde alteration of high-grade minerals (e.g. garnet and glaucophane) and the formation of well-developed glaucophane crystals (indicative of prolonged low-temperature conditions in the glaucophane stability field) during uplift; deposition of a flysch sequence occurred at this time. The plot illustrates that the uplift trajectory follows a path through the high-grade facies. The latest trajectory plot (440-380 Ma) reflects the late Silurian deformation and lowgrade metamorphism of the flysch and older units. Solid lines, calculated P - T trajectory; broken lines, estimated P - T trajectory; horizontal ruling, maxima of high-pressure metamorphism (based on mineralogy); open circles, calculated P - T conditions (reproduced with permission from Ohta, Dallmeyer & Peucat 1989). Ordovician rocks show a marked contrast between those of East Greenland and those of North Greenland (Peary Land, Washington Land) and the Canadian archipelago (Smith, Sonderholm & Tull 1989) In East Greenland the youngest Ordovician rocks, Heimbjerge Formation, are dated as Late Whiterockian, i.e. Llanvirn. This has

Forlandsundet Graben

The distinctive facies of the Kaffioyra Complex in the Forlandsundet Graben (Ohta et al. 1995) represent two likely tectonic events. The dolostone composition and metamorphism match in some degree the Vestg6tabreen (Early Ordovician complex). The dextrally sheared slices at Kaffioyra and Sarsoyra indicate a deep Paleogene transpressive phase.

14.5 14.5.1

Cambrian-Ordovician terranes and palinspastics Supracrustal comparisons

Figure 14.9 plots Svalbard Cambro-Ordovician successions with approximate correlations to Greenland and other successions. One of the most obvious contrasts which led to the hypothesis of three juxtaposed provinces, previously quite distant (Harland & Wright 1979), is that the Ordovician tectono-thermal event, followed by Late Ordovician-Early Silurian strata in the Western Terranes, was coeval with relatively uninterupreted sedimentation through to Llanvirn time in the Eastern Terranes and not very different in the central terrane. At that time not only could the Western Terranes not have been located between eastern Svalbard and East Greenland but they must have been distant. The most obvious similarity is that of the Oslobreen succession in Ny Friesland with the coeval strata in central East Greenland. Cowie (1974) noted that the Pacific Province olenellid faunas are rich in individuals and poor in species. Indeed there is similarity in faunas and facies between East Svalbard, East Greenland and northwest Scotland which on our palinspastic reconstruction would have been close together (Fig. 14.10). The Central succession (described from Hornsund in the south) has few species or even genera in common with either Ny Friesland or Central East Greenland whereas for example Olenellus svalbardensis has been recognized i~ east North Greenland. Other similarities (Birkenmajer & Orlowski 1977; Birkenmajer 1978a, pp. 1143-44) have been reported. Nevertheless the more northerly situation proposed would still pertain to the North American Pacific Province.

CAMBRIAN-ORDOVICIAN HISTORY CENTRAL TERRANES

WESTERN TERRANES CHRONSTRAT.

Ma

S2

O S C A R II LAND PRINS KARLS FORLAND

BJ~RNOYA

EASTERN TERRANES

CENTRAL SOUTH SPITSBERGEN

NY FRIESLAND

NY FRIESEAND

Wenlock (431 )i (433) (436)

Holmesletfjella Barents Bulltinden

- 430-

S~

269

Llandovery

OREGENY

CLIMAX - 430-

CALEDONIAN OROGENY

I!

- 440-

"

I

- 440(443)

tI

Ashgill

- 450-

m

0 3 --

-450-

NORDAUSTLANDET

Caradoc

Motalaf]ella

Llanvirn

Vestg6tabreen Complex

(455) t

-460-

-460-

02 -470-

O1

(?Ackfjellet)

-500-

"~3

--

476 (479)

I (HORNSUNDIAN DIASTROPHISM)

Dolgelly__

"~2

_

(Ditlovtoppen)

Solvan Toyonian Botomian Atdabanian

-530-

"~1

- 490-

r L [ i i

(5oo)

(50o) (504)

Menevian

- 520-

- 480-

?(Sparreneset)

Ki~on~ggen

(481 )

(484)

Maentwrog -510-

- 470-

Sjdanovfjellet

Tremadoc

- 490-

Valhallfonna

YMERDALEN

EIDEMBREEN TECTONOTHERMAL EVENT

Arenig

480-

466

-500-510(520) - 5 2 0 -

I Topiggane Bl~lrevbreen

Slakli faunas

Krosseya - 530-

Tommotian

- 540-

(JARLSBERGIAN DIASTROPHISM)

Nemakit-Daldyn

(538) (542)

-

(549)

- 550 -

540 -

-550(556)

-560-

V2

Ediacara

-560-

I

SCOTIA GROUP

"~ G&shamna

I

-570-

-570-

I m 7

m?m

/

m

V 1

~

Serhamna

~I~

Fannypynten

(631)

Russehamna

/X

Hansvika

Varanger

~1~ Wilsonbreen /X

(620)

Elbobreen

AlL

;

Sveanor

I1EO

(624)

Fig. 14.8. Tentative correlation of Cambrian Ordovician tectonic events in Svalbard. Triangles are Varanger tillites.

RUSSIA EASTERN PLATFORM S2 S1

PEARYA SEQUENCE IV

SIBERIA

I

Wenlock Llandavery

j ~. i

03. Caradoc /M

Llanvirn

St Davids

'~1

V2 M1

Ediacara

:erne

liltll

Toyonian ~ Botomian Atdabanian Tomrnotian NamakitDaldyn

~

Ell ~

9C 2

CALEDONIAN NORTH EAST GREENLAND

CENTRAL SVALBARD

CLIMAX

EAST SVALBARD

OF

EAST GREENLAND

N.W. SCOTLAND

CALEDONIAN

W. NFLD

OROGENY

q,EIDEMBREEN , TECTONO_ 1' THERMAL

I I I I I I I

Vergale Lontova Rovno Kotlin Redkino

EVENT

PLUTONS//

lit 9 Perekhod~ ~ ~ Petrotsvet

t

'

t 1

i t

1 1 I

q q

)

t F

? _,~_ Danmarks Fjord Kap Holbrek Fyn $0

q q q i i

I

Comfortless-

I

breen St Jonsrjorden etc

.... 1

North of latitude __ _ _ . L - _ _ _ _ 74~ tothe northern ...... Christian Land at Serkapp Land about 82~ the 800 km Caledonian fold belt east of H~N~N~N the thrust fault exposes only Precambrian or cover rocks, Reunian . . . . . ?Br~nland Fjord throughMesguire Wandel Valley

/

Been Portfield Moraen sa

t

) Scotia etc

Borglum River

Perleporten

q t

Varanger

Ante rct ic rie IIe t

1

Manychai Yudoma

~

Amdrup _?_

'

99 9

ausve

~)pi~-na

/ ./

Milne Fiord

fold belt Centrum

,

,.//GRANITE

Tremadoc

Merioneth

PEARY LAND: EASTERN NORTH GREENLAND

BJORNOYA

Pmfi fJe det (S,

i ; ~ ihr .en

CLINTOCK/.

///'//x//.

"~3

I

Egonwah

/~ OROGENY'/.

Arenig 01 "

I

KRONPRINS I CHRISTIAN LAND: [ N. PLATFORM GREENLAND

Hadey River

Ashgill

02

W. SVALBARD

JARLSBERGIAN

-

Valhalllf~

?Na h ~;S ed Kap Weber

I Kirton?yggen

Cass Fiord

il I

7-

?

~?

?Antiklinal Bugt

I ~

?Dolomite Point - ~yoli~-u~

I

Tokammane_l --~ II _ __ _ -- . . . .

I

K'~

~

I

.........

rin

I c%~% L ~1 Sangamore Ba,nakia, I~ c I j

.........

'~'z ~

Eilean?Dubh I

Grud~dh

/

Serpulite Gdt * FucoidBeds Eriboll Sandstone ,

St George ? Petit Jardin Hawke Bay Forteau Bradore

?

?Campanuladal G~shamna Fsnnypynten

Bj~rn~ya

Polansbreen etcl

I I

Tilffte Group I

I I

Torridon Sandstone

Fig. 14.9. Schematic correlation of North Atlantic-Arctic Early Paleozoic sequences. The Iapetus Ocean is thought to have opened in latest Vendian or earliest Cambrian time (e.g. Anderton 1982). Faunal contrasts between 'Pacific' and Acado-Baltic Provinces (Cowie 1974, figs 6-7) may have increased up to Early Ordovician time and, from Middle Ordovician time, decreased as the ocean closed. The relationship of Bjornoya to the other Svalbard terranes is problematic. A surprising fact has emerged (M.P. Smith pers. comm.) 'The sequence stratigraphy (well constrained by the conodont data) indicates that Bjerneya was almost certainly a

part of the Laurentian craton and was attached to North Greenland until early rifting (which explains the westward vergent regional structures). The Early Paleozoic Bjernoya sequences match only those in Peary Land and Kronprins Christian L a n d they contrast significantly with the remainder of Svalbard, East Greenland and western North Greenland'. Perhaps the most conspicuous relationship, now generally accepted, is that Svalbard's Western Terranes have much in common with the Pearya terranes in northern Ellesmere Island.

270

CHAPTER 14 Early Ordovician (c 490 M I

.

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Eastern Svalbard Terranes

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Fig. 14.10. Schematic illustration of the Cambrian-Ordovician palinspastic configuration of Greenland and adjacent terranes according to the strikeslip hypothesis conjectured in this work. Present-day coastlines are used for identification only since the substantial Silurian through Devonian, and later Cenozoic tectonism and displacements of coastlines cannot be depicted accurately. Thus, Ellesmere Island (with Pearya) is placed further east of its present position, but the Paleogene deformation was distributed through much more of the island rather than along the Nares Strait as drawn here. Similarly, the fragments of Svalbard have not been reconstructed to take account of the combined effect of mid-Paleozoic and Paleogene deformation, nor has Svalbard been broken into its pre-Caledonian configuration. The subsequent mid-Paleozoic faults and orogenic fronts have been dashed to illustrate future boundaries. Perhaps the only line then existing, but whose position is uncertain, is the NW margin of the Iapetus Ocean.

Trettin (1987) showed Pearya to be a composite terrane assembled by sinistral strike-slip faulting and he related it to the Caledonian succession further to the east. Whereas the interpretation here accepts the original proximity of western Svalbard and at least Trettin's succession IV in Pearya, it is argued in this work that the Svalbard Western Terranes escaped the main Caledonian orogeny. Fig. 14.10 illustrates roughly how the Svalbard Western Terranes could have originated north of Greenland and west of the later Caledonian thrust front. They thus belong together in the Pearya province east of Ellesmere Island and west of the Caledonides. In consequence, as illustrated diagrammatically in Fig. 14.10 Svalbard is conjectured to be a composite terrane with its constituents from four original provinces belonging to the margins of Greenland. (i) The Svalbard Eastern Terranes (Ny Friesland and Nordaustlandet) belonged to the East Greenland Province with which they have close affinity in both Early Palaeozoic and earlier successions. (ii) The Svalbard Central Terranes (middle Hornsund Cambrian -Ordovician sequences) must have occupied a position to the north i.e. the North East Greenland Province. It fell equally within the Caledonian East Greenland Fold Belt. It is argued here that the narrow coastal outcrops of North East Greenland may be followed

south into the metamorphic complex of East Greenland but that the Vendian through Carboniferous record would be lost (in the sea) east of coastal metamorphics. Indeed the Central Terranes of Svalbard, and notably here the middle Hornsund sequences represent the eastern missing part of the North East Greenland Caledonides. (iii) Bjornoya, following the conclusion by Armstrong & Smith (in press), is a relict of the most northerly extension of the Greenland Caledonides, where it remained until separated from Greenland and joining Svalbard by the Cenozoic dextral strike-slip faulting. (iv) The Svalbard Western Terranes belong to the Pearya Province with an Early Paleozoic location north of Greenland and west of the Caledonian front. At that time the ocean Iapetus had opened and was closing through the Cambrian and Ordovician periods. It is possible that the lack of identifiable early Siberian strata (Atdabanian, Tommotian and Nemakit-Daldyn) may be accounted for by the diastrophic effects of the opening of Iapetus. The Iapetus closing heralded the mainly Silurian collision hence the general lack of significant post-Llanvirn strata within the East Greenland Caledonides or the Eastern and Central terranes of Svalbard. Fig. 14.11 illustrates an Early Ordovician palinspastic reconstruction showing the relative positions of Laurentia, Baltica and Siberia according to Torsvik et al. (1996).

14.5.2

Tectono-thermal events

Isotopic age determinations from Svalbard, as for example compiled by Ohta (1992), if plotted according to the three terranes and subterranes show a scatter which, because of the varied materials analysed, the unsystematic distribution of locations, and the different analytical methods developing over a span of thirty years, it would not be profitable to assess briefly. Nevertheless, there is a clear impression that the data from the Western Terrane, especially from Motalafjella, indicate a concentration of Ordovician ages, in contrast to the Central and Western Terranes where Silurian ages predominate. This impression is reinforced if determinations only by the latest methods are considered. These data support a stratigraphic contrast and point to the western terranes not being in the typical Caledonide belt, but more akin to North Greenland, and the Queen Elizabeth Islands i.e. a M'Clintock and Ellesmerian rather than a Caledonian relationship. More significantly and more recently is the analysis of 'Pearya' a complex terrane at the northern tip of Ellesmere Island by Trettin (1987). He found Pearya to comprise four successions or sinistrally docked slices. His successions III and IV represent a close parallel to the Ordovician story in Oscar II Land. Succession III is of arc-type, with ocean-floor volcanics and ultramafic complex, probably Early to Middle Ordovician and thrust over succession II (miogeoclinal sediments and volcanics from Late Proterozoic (Hadrynian) to latest Cambrian or Early

CAMBRIAN-ORDOVICIAN HISTORY Ordovician) during the collisional mid-Ordovician M'ClintockOrogeny. Unconformably overlapping succession III and parts of succession II is succession IV i.e. Late Middle Ordovician to Late Silurian sediments and volcanics. Whereas Trettin argued that Pearya (a composite terrane) had, by sinistral strike-slip, affinity with the Caledonides. It is argued above to have been located west of the Caledonides. Trettin, Parrish & Roddick (1992) obtained further. A r - A r determinations from a syntectonic granodiorite: monazite gave 475 • 1 and biotite 467.8 + 2.5 Ma. These values Early Llanvirn and Llandeilo from Harland et al. (1990) were said to shift the onset of the M'Clintock Orogeny of the Pearya Terrane from early Middle Ordovician as previously assumed to Early Ordovician'. However the Tucker & McKerrow (1995) time scale as used in this work make those ages late Arenig and Early Llanvirn. The obvious connection is for the Eidembreen tectogenesis, and possibly subduction, to be part of the M'Clintock Orogeny. The usual Carboniferous continental fit places western Svalbard only about 400 km from Pearya. Also in central Ellesmere Island there is a stratigraphic gap representing a middle Ordovician disturbance between the Caradoc Cornwallis Group and the (Arenig-Tremadoc) Canadian Bauman Fiord Formation. The timing would correspond to the Bauman Fiord and West Spitsbergen Eidembreen metamorphism and upthrusting. There appears to be no equivalent Cambro-Ordovician phase in the Scandinavian Caledonides since the evidence for a Finnmarkian episode has been virtually eliminated (Townsend & Gayer 1989).

14.5.3

Conclusion

Cambrian-Ordovician history contrasts events in the west with those of the Central and Eastern Terranes where undisturbed sedimentation continued through Vendian and Early Cambrian to mid-Ordovician time and was followed by Late Ordovician and Silurian tectogenesis belonging to the Caledonides. In the Western Terrane during Early to mid-Ordovician time, deep tectogenesis- possibly in a subduction zone was in progress, this was followed by somewhat disturbed sedimentation through Silurian time when the Ny Friesland Orogeny was in progress and then no record of Devonian events persists, when in the Central Terrane disturbed ?latest Silurian through Earliest Devonian sedimentation ensued followed by increasingly stable Old Red Sandstone facies.

271

This tectonic sequence matches more closely that of the Queen Elizabeth Islands which was why Harland & Wright (1979) proposed an Ellesmerian rather than a Caledonian sequence for the west. However, the more significant Ellesmere Island affinity is seen in the M'Clintock Orogeny in its northern allochthonous terrane (Pearya of Trettin 1987). This premonition of Silurian-Caledonian and DevonianEllesmerian tectonism leads on naturally to Chapters 15 and 16 respectively. At the same time, whereas Svalbard still belonged to Laurentia it was joining Baltica (Harland 1967) which had its own story (e.g. Torsvik et al. 1991). Indeed, Iapetus was a distinctive feature of Cambro-Ordovician time with its opening and closing. The configuration on the margin, away from Laurentia, probably changed radically while separated from Laurentia and we can only be sure of their final juxtaposition resulting from the Caledonian orogeny (e.g. Granow, Hanson & Wilson 1996). The final closure of Iapetus with tectonization is part of the Silurian story. The ocean certainly existed for most of Cambrian time. Figure 14.10 shows a somewhat detailed proposal for the configuration of the Laurentia margin. There is very little reliable constraint or consensus on the nature of the opposing margin. Three recent models follow which are each based on evidence outside the scope of this work. Prigmore, Butler & Woodcock (1997), on the basis of subsidence analysis of rifting during separation of Eastern Avalonia from Gondwana, depicted an Arenig (480 Ma) reconstruction for Iapetus with Baltica, widely separated from Greenland, oriented about 90 ~ clockwise from the present, and about 30 ~ latitude south of Greenland. Niocaill, Pluijm & Van der Voo (1997) from palaeomagnetic data depicted two Ordovician configurations (Early-Mid- and Mid-Late) with Exploits Arc and Pan-Avalonian Arc within the Iapetus Ocean. Baltica turns anticlockwise as it approaches and contacts Laurentia, with Late Ordovician-Early Silurian relative orientation as at present. Dalziel (1997), in a wide-ranging hypothetical NeoproterozoicPaleozoic palinspastic speculation, suggests for Arenig time that an Avalon-Midland valley of Scotland arc separated a Neo-Iapetus Ocean on the Laurentian side from a wider Palaeo-Iapetus bordering an unrotated Baltica. A Middle Cambrian Western Iapetus was shown as a wide ocean between Laurentia and South America and an Eastern Iapetus between Greenland and Baltica (rotated 180~ It may be too much to expect at this time that any one author, and certainly not this one, could master sufficient global data for a consistent series of palinspastic maps.

Chapter 15 Silurian history W. B R I A N

HARLAND

Silurian time, 272 Silurian time scale, 272 Biostratigraphic correlation, 272 Isotopic age correlation, 274 Silurian supracrustal events: sedimentation and tectonics, 275 West Spitsbergen, 275 Northwest Spitsbergen, 275 Silurian tectonic source, 275 Silurian tectonic sink, 275 Silurian tectogenesis, 275 Nordaustlandet, 276 Ny Friesland Orogeny, 276 Northwestern Spitsbergen, 278 Western Svalbard, 279 Southwestern Spitsbergen (Wedel Jarlsberg Land), 279 Southern Spitsbergen, 279 Bjornoya, 280 Summary of tectonic vergences, 280

15.4 15.4.1 15.4.2 15.4.3 15.4.4 15.4.5 15.4.6 15.4.7 15.4.8 15.4.9 15.4.10 15.5 15.5.1 15.5.2 15.5.3 15.6

Silurian petrogenesis of crystalline rocks, 280 Metamorphism of sedimentary rocks, 280 Layered gneiss, 281 Migmatites, 281 Granites, 281 Syntectonic (grey) granites, 282 Late tectonic plutons, 282 Stratiform feldspathites, 283 Feldspathic (augen) schists, 283 Shear zones and mylonites, 283 Mafites, 283 Silurian terranes, provinces and palinspastics, 284 Grouping of terranes by province, 284 Silurian fault and shear motions, 286 Baltica, Barentsia and Iapetus, 287 Sequence of Silurian (main Caledonian) events, 288

Treatment in this chapter of the Silurian episode in the history of Svalbard must be different from that of the preceding and succeeding chapters because the stratal record is quite m i n i m a l - a fact that corresponds to the widespread Caledonian tectogenesis (Fig. 15.1). Indeed, Svalbard was subjected to mid-Paleozoic orogeny which has often obscured the earlier history. This chapter, therefore, concentrates on the tectonic story even where it overlaps earlier and later history and in turn the preceding and succeeding chapters overlap to some extent with the sedimentary record. Historically the metamorphic rocks were first regarded as Archean. Holtedahl (1914) demonstrated their Caledonian nature first in northwestern Spitsbergen and later regionally (Bailey & Holtedahl 1938). It was, however, then a paradigm of tectonic thinking, perhaps by analogy with Wales, that the Caledonian Orogeny was conceived as deforming an Early Paleozoic geosyncline (Cambrian through Silurian). This was evident in early interpretations of Scandinavian, Greenland and North American mapping as well as in Svalbard. It was commonly thought that those geosynclines would begin with an initial Cambrian unconformity. Gradually, however, it became clear that the 'Caledonian' geosynclines were more complex and in each of the areas referred to above the major part of the sedimentary pile was found to be Precambrian, often with no great sedimentational break to herald the Phanerozoic Era. Latterly interest has focused on distinguishing, within the Caledonized Precambrian successions, relicts of earlier pre-Caledonian mainly Proterozoic orogenies referred to here as protobasement.

15.1.2

Biostratigraphie correlation

15.1 15.1.1 15.1.2 15.1.3 15.2 15.2.1 15.2.2 15.2.3 15.2.4 15.3 15.3.1 15.3.2 15.3.3 15.3.4 15.3.5 15.3.6 15.3.7 15.3.8

15.1 15.1.1

S ilu ria n t i m e Silurian time scale

In contrast to the 80 million years (reduced lately to little more than 50 million years) duration of the Ordovician Period, the Silurian Period was relatively short (31 reduced lately to 26 million years) and classification, nomenclature and definition of the divisions are well established. This would give grounds for confidence in any correlation were there good Silurian faunas in Svalbard. Such are sadly lacking and the main dateable record is of isotopic age determinations. Consequently the table (Fig. 15.2) represents only the established epochs with no Svalbard application of stages or chronozones.

There are only three recorded successions in Svalbard of Silurian or potentially Silurian strata: Bullbreen Group in Oscar II Land; Grampian Group in Prins Karls Forland; and Siktefjellet Group north of Liefdefjorden. Successions penetrated by deep wells in Edgeoya according to Shvarts (1985) might yield Silurian and Ordovician data, but that is not supported in this work.

Bullbreen Group (see Chapters 9 and 14). Whereas the lower Motalafjella Formation is almost certainly of Late Ordovician age the overlying Bulltinden (conglomerate) Formation is also fossilbearing and of Silurian age. Two assemblages were collected and reported by Scrutton, Horsfield & Harland (1976): Assemblage (1) was from fossiliferous boulders in the conglomerate and includes mainly corals: rugosans: Ketophyllumreferred to Dokophyllum a ?Kodonophyllid a probably fasciculate Tryplasma tabulates: Paleofavosites Catenipora sp. brachiopods: thickshelled pentamerines, probably Harpidium sp. (= aft

Lissocoeina) gastropods: a bellerophontid also small orthocones, bryozoans and echinoid spines crinoid ossicles are common. one specimen of a dendroid stromatoporoid Scrutton (et al.) remarked that, although Paleofavosites, Cateniphora and Tryplasma occur in both Ordovician and Silurian rocks, Ketophyllum is not recorded prior to Late Llandovery and Wenlock; and Harpidium (=aft. Lissocaelina) is restricted to Late Llandovery and Wenlock. Only Tryplasma is recorded in beds younger than Silurian. The Bulltinden Conglomerate Formation was therefore (tentatively) thought to be 'derived from a Silurian horizon of probable Late Llandovery or Wenlock age, although a Ludlow age cannot be definitely excluded'. Assemblage (2) of only 16 specimens, was collected from the slumped limestone olistostrome and six specimens were of Paleofavosites sp. other material matched the above except that the pentameran brachiopod appeared to be thinner shelled than those referred to above. There is no reason to distinguish the age of the two assemblages. Further collections from both the Motalafjella and Bulltinden formations were made by Ohta and others and reported on by Armstrong, Nakrem & Ohta (1986). The Motalafjella Limestone fauna of Ordovician age has already been referred to in Chapter 14. With regard to the

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SVALBARD SILURIAN O U T C R O P S AND TECTONISM

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274

CHAPTER 15 Ma Epoch

D

Harland et al. 1990 Tucker& McKerrow 1995

Lochkovian

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between the Groups. Against this, on the other hand, is the finding of Friend e t al. (1997) that both groups appear to have been subject to relatively continuous diastrophism with generation of conglomerates from sinistral, strike-slip fault scarps. No more is done here than refer to these rocks as ?Silurian. However, their story of the interplay of tectonics and sedimentation will be treated in the next chapter along with the well dated Red Bay Group.

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Edgeoya. Of the two deep wells drilled in Edgeoya, Plurdalen I and Raddedalen 1 only one record was made public (Shvartz 1985) on Raddedalen: At 874m a basal 'Culm' unconformity was reported and at 1819m below Early Silurian and Ordovician phytogenic and zoophytogenic strata were discribed. The Cambridge Group do not confirm the ages (Sections 5 . 7 . 3 and 5.9).

A ~

Fig. 15.2. Summary of Silurian time scales. The Harland et al. (1990) calibrations were based on the best available tie-point and values in each division were distributed between them. The Tucker & McKerrow (1995) values include late tie-points based on new and better (zircon) determinations. This is a good illustration of the variable uncertainties of different segments of the time scale.

Bulltinden conglomerate they confirm or report the above findings of Scrutton et al. and additional fossiliferous localities were reported with gastropods, corals, cephalopods and trilobites. There is some ambiguity in the conodont investigations because the conglomerate clearly contains material not only penecontemporaneous but also eroded from both the Motalafjella Limestone and the underlying Vestghtabreen metamorphic complex. However most samples investigated for conodonts were from the Motalafjella Formation according to their map. Their Bulltinden Formation is equivalent to Bulltinden Group as used here. Therefore our knowledge of the age of the Bulltinden conglomerate is hardly advanced by these studies, and a Silurian age is preferred here. The uppermost Holmesletfjella Formation in the Bullbreen Group is rich in trace fossils, but no body fossils have been recorded. It comprises sandstones, siltstones and shales often with rhythmites, probably turbiditic. This has been assumed also to be of Mid- or late Silurian age. Its lithology is similar to the finer parts of the conglomerate.

Grampian Group (see Chapters 9 and 14). In Prins Karls Forland the Grampian Group rests on the Scotia Group with Ediacara microbiota. Within it, a middle (Barents) Formation of rhythmites recalls those of the Holmesletfjella Formation. In addition the Sutorfjella conglomerate Member in the Barents Formation contains schist or phyllite of Scotia type. This has already been suggested as further evidence of midOrdovician diastrophism, equivalent to the Eidembreen Event in Oscar II Land and the M'Clintock Orogeny of Peary Land in north Ellesmere Island. A Silurian age for the upper part of the Grampian Group, or all of it, would be consistent with the evidence, but cannot positively be asserted.

Siktefjellet Group.

In the Biskayerfonna peninsula, especially at Siktefjellet just north of Liefdefjorden, is the oldest (Siktefjellet) group in the (Old Red Sandstone) Liefde Bay Supergroup and is discussed in Chapter 16. Although trace fossils and plant fragments have been observed within the Siktefjellet rocks no dateable biota has yet been recorded. Overlying the Siktefjellet Group is the Red Bay Group. It contrasts with the grey colour of the Siktefjellet Group and contains fossil fish of Lockhovian (Gedinnian) age in almost the lowest beds, i.e. earliest Devonian. Therefore there is the possibility that the Siktefjellet Group or part of it could be Silurian. In support of this was the case for a post-Siktefjellet pre-Red Bay Haakonian diastrophism (Gee 1972) suggesting a time interval

15.1.3 Isotopic age correlation Age in years of Silurian events depends on a variety of isotopic determinations spanning more than thirty years. During this time the problems investigated have varied, methods have advanced and for the most part they were reconnaissance rather than systematic studies. There has also been a tendency to discard anomalous results. It would not be profitable here to review each item critically. One broad result is clear that except in the west coastal regions where Ordovician ages predominate, elsewhere there is a concentration by latest work of Silurian tectonothermal activity. Possible Silurian ages are plotted in Fig. 3.9. The interest of most recent investigations has been to discover by ancient values, through the Caledonian overprint, the existence of proto-basement. In this search perhaps the constant mid Paleozoic results might have been regarded as failures, or at least not of inherent interest for that investigation. Only one recent study (which confirms earlier results) gave rather consistent mean Wenlock ages for the Ny Friesland tectonothermal event (Gee & Page 1994). A plot of radiometric age determinations for all Svalbard (Fig. 3.9) distinguishes the scatter of early reconnaissance data by methods largely superseded. Considering these in relation to the 12 terranes in that plot the following conclusions may be drawn. From the west coastal terranes southern Wedel Jarlsberg Land yielded only Precambrian data. From northern Wedel Jarlsberg Land, Hauser in Ohta (1992) obtained a scatter of K-Ar results from three Ordovician values, no Silurian, one Devonian and three Carboniferous, all from the same rocks which were within the Paleogene deformation belt. Also by K Ar methods Krasil'shchikov et al. (1964) recorded just one Devonian value. Indeed the only rocks seriously investigated have been the Vestg6tabreen Complex of Oscar II Land. Horsfield (1972) by K A r on the same rocks recorded two Ordovician ages, one Silurian and one Devonian. Of more recent attempts Dallmeyer (1989) by 4~ recorded one Silurian age (433 Ma) similarly Ohta (1992) reported one (436 Ma). The Silurian values are all mid-Llandovery on Tucker & McKerrow's scale and early Llandovery on the Harland et al. scale. However, the two focused attempts on the Vestghtabreen Complex by Dallmeyer et al. (1990) by U Pb, Sm-Nd and REE determinations concluded combined results respectively 466 and 476 Ma, i.e. Llanvirn and Arenig ages which are consistent with biostratigraphic estimates. From the above it may be argued that there is no good reason to consider a Silurian thermal event in the Western Terranes. The western northwest Krossfjorden Group metamorphic terrane with one (inherited) exception (Balashov et al. 1996) has yielded no reliable age earlier than Silurian and a nearly equal number of Silurian and Devonian values. Of these the Devonian values were all early determinations by Hamilton et al. (1962) by Rb-Sr and K-Ar and Krasil'shchikov et al. (1964) by K-Ar methods. Moreover, these same attempts spread equally into the Silurian span. Of later determinations one result 429 by K-Ar (Ravich 1979) and three results 420, 425 and 433 ma on the granite pluton by Ar-Ar methods (Dallmeyer 1989) are all Llandovery to Ludlow. A definite (mainly mid-Silurian) thermal event (Smeerenburgian) is thus indicated.

SILURIAN HISTORY The Biskayerfonna-Holtedahl terrane exposes two metamorphic sequences: the Krossfjorden Group and the Richarddalen Complex. In both cases early and late determinations are distinguished of which the later (Dallmeyer et al. 1990) must be regarded as the most reliable. Here the Krossfjorden Group correlates closely with that in the western northwest sector. Earlier determinations of 438.5 and 389 Ma were by K-Ar methods (Gayer et al. 1966) indicated mid Silurian and Early Devonian without any pre-Silurian result. The later (Dallmeyer et al.) Ar-Ar, and Rb-Sr values were four Silurian (437, 429, 428 and 413 Ma) and one Devonian (410Ma) ages. This is consistent with the northwestern sector. The Richarddalen Complex on the other hand is unique in providing ages from 3234 through 397Ma. The early results (Hamilton et al. 1962) were 538, 433 and 397 Ma and Gayer et al. (1966) yielded only Precambrian ages. Consequently the only data worthy of consideration for Silurian ages are those of Dallmeyer et al. which spread from Ordovician 455Ma, through 443,433,430,423 and 418 (all just Silurian) and 410 Ma. Therefore it is concluded that superimposed on a long earlier tectonothermal history was a clear Silurian imprint. In western Ny Friesland, east of the Billefjorden Fault Zone, early K Ar results of Phanerozoic age (Gayer et al. 1966) defined five closely grouped values: 444, 442, 434, 430, 427 mainly Llandovery ages. A later more reliable result from several determinations (Gee & Page 1994) confirmed a Silurian age and probably late Wenlock at 424 Ma. A U-Pb zircon age of 410 Ma (Johansson et al. 1995) must be reliable and would indicate the late tectonic Early Devonian igneous episode. In eastern Ny Friesland probably the same igneous episode is more evident in two or three batholiths for which the earliest K-Ar determinations (Hamilton et al. 1962) gave 426, 425, 413, 395, 392Ma all from the same granite locality and other localities yielded 428.4 and 422 Ma. A late Silurian-Early Devonian cooling age was indicated. However, Teben'kov et al. (1996) obtained Rb-Sr whole-rock ages of 432 + 10 Ma, i.e. a pre-cooling Early Silurian age. This eastern terrane is only marginally metamorphosed and no other ages have been obtained. In Nordaustlandet as a whole there are Devonian or later ages forthcoming, which are discussed in Chapter 16 but with two Silurian exceptions, and these are only from early determinations: 442.6Ma in the west and 419.3 Ma in the east (both from Gayer et al. 1966). In conclusion, the following broad generalizations emerge. There is not sufficient evidence of Silurian thermal activity in the Western Terranes (south of Kongsfjorden). North of Kongsfjorden the metamorphosed Krossfjorden Group, both in the western northwest and in the Biskayerfonna terrane, shows clear Silurian activity as the first tectonothermal event there. However, the Richarddalen Complex with a long Precambrian thermal history also received the same Silurian thermal imprint. East of the Billefjorden Fault Zone, also superimposed on a Precambrian thermal event, is a similar clear mid to late Silurian tectonothermal record and this was followed by an acid igneous phase of latest Silurian to Early Devonian age. The Silurian tectonism extended through eastern Ny Friesland and through at least western Nordaustlandet but with little or no isotopic record.

15.2

15.2.1

Silurian supracrustal events: sedimentation and tectonics West Spitsbergen

It has been noted that the only certain Silurian sedimentation is preserved in the upper part of the Bullbreen Group in western Spitsbergen and that this probably corresponds to analogous sedimentation in Prins Karls Forland. These deposits indicate disturbed conditions with boulder-bearing conglomerates, slumped masses, and turbidites. Because of the small area of outcrops and the subsequent effects of Paleogene tectogenesis a dominant direction of transport or provenance has not yet been identified. Following complex Ordovician sedimentary and tectonic events as recorded in Chapter 14 both Oscar II Land and Prins Karls Forland received siliciclastic sediment with turbidite and conglomeratic facies. Thus, the Western Terranes, having been tectonized in

275

the Early to mid-Ordovician Eidembreen Event, became stable enough to receive and preserve sediment derived from erosion of the Silurian Smeerenburgian and other Caledonian orogens.

15.2.2

Northwest Spitsbergen

The other possible Silurian window on supracrustal events may be seen in the Biskayerfonna-Holtedahlfonna terrane. This is bounded on the west by the Raudfjorden Fault and on the east by the Breibogen Fault. Each of these will be argued to be fundamental faults with a major strike-slip history. The later sediments, which tell the story, are biostratigraphically dated as early Devonian (Red Bay Group). However, the strata beneath with no direct evidence as to age could be still earlier Devonian or more probably late Silurian (Siktefjellet Group). The sedimentary evidence is similar in each group with dominantly sandstones and conglomerates of highly variable facies with intermittent supplies of boulders and pebbles and evidence of compression and extension. This has been interpeted (Friend e t al. 1997) as sedimentation in a strike-slip regime with local small-scale transpression and transtension leading to erosion of intermittent fault scarps with local sources of proximal sediment often large boulders. This story is resumed more fully in the Devonian chapter (16).

15.2.3

Silurian tectonic source

From the above rather limited and indirect evidence a major orogenic episode emerges, with collisional tectonics developing in Early Silurian time. By latest Silurian time the major compressive phase had ceased in northwestern Spitsbergen and strike-slip was already operating after an intermediate transpressive phase.

15.2.4

Silurian tectonic sink

Silurian events in North Greenland as postulated by Hurst e t al. (1983) throw light on events in Svalbard. A platform supporting Ordovician and early Silurian carbonate sedimentation occupied the area of eastern North Greenland west of the northern extension of the East Greenland Caledonides and south of the North Greenland Fold Belt. With the closure of Iapetus in Late Ordovician to early Silurian time collisional orogeny ensued with i.a. thin-skinned thrust sheets extending westwards on to the platform. This had the two-fold effect of shedding turbidites westwards on to the platform which itself subsided in response to the advancing nappes. The northern margin of the platform (later occupied by the DevonianCarboniferous Innuitian or Ellesmerian Orogen) was then a deeper basin in which similar and thicker westward-directed turbidites (and conglomerates) extended through the whole axial length of the basin. These events were largely accomplished in Llandovery time.

15.3

Silurian tectogenesis

The overwhelming conclusion from investigations throughout this century is that Svalbard, or most of it, belongs to the mid-Paleozoic Caledonian Orogen. Moreover that, whereas diastrophism began most probably in mid-Ordovician time with the closure of Iapetus Ocean, the principal tectogenesis, and certainly the main metamorphism was of Silurian age as has been confirmed by m a n y isotopic studies. Where this work may differ from some opinions is in the exclusion of central-western and southwestern Spitsbergen terranes from the Caledonides. Nordenski61d (e.g. 1867) had distinguished the crystalline rocks as the oldest amongst which he distinguished: (A) granite-gneiss and (B) crystalline schists. Nathorst (in Suess 1888) mapped these as Archean, in three principal terranes: Nordaustlandet, N y Friesland and Northwest Spitsbergen. Holtedahl (1914) demonstrated that the

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crystalline rocks of northwestern Svalbard were Caledonian. In the east, however, Sandford (1926 through 1956) speculated on the Nordaustlandet crystalline rocks as being basement and puzzled over their contact with the cover rocks. The idea of a Barents Precambrian craton occupying eastern Nordaustlandet was sustained by Russian geologists (e.g. Krasil'shchikov 1965, 1973) who distinguished only eastern Nordaustlandet as Archean-?early Proterozoic crystalline basement with Caledonian tectogenesis in contrast to the other crystalline terranes which were regarded as parts of the lower Hecla Hoek Complex.

15.3.1Nordausflandet

Five terranes are discussed, listed from the west. It is concluded that the Caledonian tectogenesis decreased eastwards against the Proterozoic foreland (the Duvefjorden Complex). (i) Western Gnstav V Land (WGVL) is characterized by the upper middle part of the Hecla Hoek succession and down to the Kapp Hansteen Group with volcanics. Related granites yielded isotopic ages of about 950 Ma (Gee et al. 1995). These rocks occur in upright open folds. The earlier opinion as to isoclinal folding (Kulling 1934) depended on assumptions about repetition of strata which have not been sustained. Current opinion thus makes the succession thicker than was first thought. There is no obvious direction of vergence Gee (in Flood et al. 1969), but Gee & Teben'kov (1996) inclined to westerly vergence. In Botniahalvoya, the Early Neoproterozoic Kapp Hansteen Group is seen to rest unconformably on a truncated folded sequence of the Brennevinsfjorden Group. (ii) North Gustav V Land (NGVL). Granites and migmatites dominate the outcrops in Laponiahalvoya and Sjuoyane. For a time they were recently taken to be Caledonian granites but have proved to be early Neoproterozoic with a Devonian overprint (see Chapters 12 and 16). (iii) Eastern Gnstav V Land (EGVL). Further to the east on the west side of Nordenski61dbukta and Rijpfjorden and south to eastern Wahlenbergfjorden lower formations of the middle Hecla Hoek sequence crop out. The fold structure of the above terranes (I), (ii) and (iii) is Caledonian. Terrane (ii) above is anticlinal and plunging south and Terrane (iii) here forms its eastern limb as was the more intense synclinorium on the western limb of terrane (i). (iv) Prins Oscars Land (POL) is dominated on the west (east of Rijpfjorden) by granites and migmatites. They underlie and penetrate wide expanses of the Austfonna Group/Kapp Platen Group which occupy most of Kapp Platen in the north and tracts down the east of Walhlenbergfjorden. New isotopic age determinations suggest that this terrane is analogous to (ii) above. (v) Orvin Land / Storoya & Kutoya (OLSK). The remainder of eastern Nordaustlandet is largely ice-covered (Austfonna) but the north exposures reveal typical migmatic terrane. It now seems unlikely, as indeed it did originally, that this terrane is the product of Silurian tectonothermal activity. It is guessed here as early Neoproterozoic.

15.3.2

(Fairbairn 1933) and not necessarily within the Hecla Hoek which was typified by the eastern stratigraphy (e.g. Odell 1927) and not least by the eponymous mountain, now named Heclahuken after Party's ship Hecla that wintered there in 1827. The first reconnaissance of the whole of Ny Friesland by a Cambridge group between 1938 and 1965 (Harland & Wilson 1956; Harland 1959; Harland & Masson-Smith 1962; Harland et al. 1992) led not only to the discovery of the Early Cambrian Salterella in the uppermost kilometre of carbonates in an 18 km pile of strata, but from mapping it was concluded that there was no obvious break in the whole succession except possibly near its base (Harland & Wilson 1956). The whole orogeny was thereafter identified as Caledonian (Harland 1959), later confirmed isotopically (e.g. Gayer et al. 1966; Gee & Page 1994) and chronostratically as post partLlanvirn and pre-Tournaisian (Fortey & Bruton 1973 and Playford 1962, 1963 respectively). It is convenient to refer to the eastern and western outcrops as separated by the Veteranen Line (Harland et al. 1992). They are stratigraphically as well as structurally distinct as shown in Table 15.1 (after Harland, Wallis & Gayer 1966). Whatever may be the significance of the unconformities and the feldspathites discussed in Chapter 7 the only major tectogenesis identified affected the whole pile in Silurian time. In general, the strata dip steeply to the E and are approximately vertical beside the Veteranen Line. Although the western outcrop was metamorphosed throughout, the metamorphic boundary does not coincide with the Veteranen Line: In northern Ny Friesland Polarisbreen rocks to the east are sheared and altered to chlorite grade. Eastern Ny Friesland folds are generally upright and rather tight where the competent Middle Hecla Hoek pinches the Polarisbreen shales into sharp synclines. Tight folding is also evident along the sides of two or three late tectonic granite batholiths which have shouldered their way up and attenuated the adjacent strata to E and W. There is a general tendency throughout for strata to young eastwards and so accommodate both 18 km thickness in an outcrop width of 30-50 km, and conspicuous thick-skinned folding. Western, in contrast to eastern, Ny Friesland exhibits a major N-S antiform (the Atomfjella Arch) towards the west and which exposes the oldest strata in its core. Recumbent folds are also evident verging westwards (Fig. 15.3). A feature throughout is a N-S lineation parallel to the fold axes - more or less horizontal but plunging gently N or S. This is evident not only in mineral elongation but also in extensive boudinage and in the psephite (Rittervatnet Fm) with elongation of stones (e.g. of dolostone) in a pelitic matrix. At first the evidence of N-S extension was taken as a response to vice-like E-W compression, commonly today referred to as an indentor mechanism (Harland & Bayly 1958; Harland 1959), leaving unexplained where, to the north and south from the 150km or

Table 15.1. Eastern and western outcrops of Ny Friesland

West

The Ny Friesland Orogeny

The structure of Ny Friesland is at first sight quite simple. An 18km stratal pile is folded along N-S axes apparently in one deformation process so as to produce a homoaxial fold belt. There is, however, a marked contrast between the eastern, mostly unmetamorphosed, higher strata seen in relatively open and upright folds and the deeper strata which are intensely tectonized and metamorphosed, with strong penetrative bedding foliation, extensional lineation and westerly vergence. This contrast led first to the assumption that the western metamorphic terrane was Archean e.g. by Nordenski61d and Nathorst as in the map in Suess (1888) and later by Tyrrell (1922). I t was referred to as the 'Western Schists and Gneisses'

Veteranen Line I East Hinlopenstret Supergroup (=U. Hecla Hoek) Oslobreen Gp Polarisbreen Gp Lomfjorden Supergroup (=M. Hecla Hoek) Akademikerbreen Gp Veteranen Gp (conformity)

Stubendorffbreen Supergroup (=L. Hecla Hoek) Planetfjella Gp

(unconformity) Atomfjella Complex Harkerbreen Gp; with minor unconformity near base Finnlandveggen Gp.

SILURIAN HISTORY

Fig. 15.3. Field sketch of Lemstr6dmfjellet (in the Stubendorff Mountains) as viewed towards 010 ~ (from Harland 1941). longer orogen, the excess rock was extruded. Although not always obvious it had already been noted that many structures, including isoclinal folds, showed sinistral shear; but not exclusively so. This led to the alternative concept of (intense) transpression Harland (1971) (see Fig. 15.4). The indentor mechanism with extrusion or escape tectonics, subsequently popularized by Tapponier et al. (1982) was later reapplied to N y Friesland (e.g. M a n b y 1990; Ohta 1994). This extrusion mechanism, except on a small scale, has yet to be conclusively demonstrated either mechanically or historically. But the arguments favouring general transpression accompanying and/or superimposed on earlier recumbent folds (Harland 1971), rather than localized compression with escape are still viable. Thus a sequence of compression, oblique sinistral compression or transpression, and then sinistral strike-slip or transcurrence was proposed, following the closing of the Iapetus Ocean. Recent research (Witt-Nilsson et al. 1997) indicates that the Atomfjella antiform extended with slight offset to the west with a uniform axis from south to north, exposing similar strata in the core. Such a regular fold, superimposed on the nappe structures, and extending at least 140km, may be the result of continued transpression. This style of deformation is observed through a width of 20-30km. However, the deformation style was not uniform throughout. In addition to N - S extensional boudinage there was also some E - W extension in the flat-lying limbs of folds, which suggested an earlier phase of recumbent folding and thrusting. A minimum strike-slip component of the transpression structures could be worked out by detailed analysis but this has yet to be attempted. Such a minimum value would most likely be far less than the real value. A value is tentatively suggested in Fig. 16.10. The Planetfjella Formation shows exceptional extension as evidenced by the shearing of the (upper) Vildadalen Formation and the (lower) Flgten Formation with its f e l d s p a r - porphyroclasts and both with local mylonitic textures. This led to a view, not accepted here, that the Veteranen Line represented a major discontinuity in the whole structure, more significant than that of the Billefjorden Fault Zone and the chlorite schists (Manby 1990,

Fig. 15.4. Elements in tectonic sequence: compression, transpression, transcurrence. Cartoon illustrating the elements in tectonic transitions in the Ny Friesland Orogen (i) from sedimentation (Proterozoic through Llanvirn) into (ii) collisional compression with the closure of Iapetus and folding and thrusting against East Greenland craton. This results in crustal thickening but no lateral elongation. Then (iii) with the change from normal to oblique maximum principal stress, part of the developing orogen transpresses generally with a sinistral displacement shown diagrammatically as a minor shear effect. The net effect of this uniformly distributed shear was to effect a sinistral displacement of the order of 100 km. (iv) As the maximum principal stress swung round to an acute angle, a larger element of displacement took place along narrow shear zones and in some cases to faults defined by mylonites. (v) In this case the Billefjorden Fault Zone is inferred to have accommodated continuous sinistral motion with the adjacent shear zone under decreasing load as deformation of the orogen proceeded, amphibolites within the shear zone retrograded to chlorite schists. This phase is postulated to have succeeded the (Silurian) Ny Friesland Orogen by Devonian transcurrence and then transpression in the Svalbardian deformation (vi).

277

278

CHAPTER 15

1995, countered in H a r l a n d et al. 1992, 1995). Nevertheless a significant shear zone, the Eolusletta zone of Manby & Lyberis (1995), coincides with the Vildadalen Formation of Wallis (1969) and reflects a sinistral displacement of perhaps 50 or more km along vertical bedding so that different tectonized styles are juxtaposed without destroying the stratigraphic continuity. West of the western belt, with its high-grade metamorphic rocks, there is also a concentration of shear indicators, with zones ofmylonite (Manby 1990; Harland et al. 1992). This is adjacent to a zone 2 - 3 k m to the west of chlorite schists retrograded from amphibolites at a lower burial depth: the Cambridgebreen Sheer Zone. This episode is interpreted as transcurrence rather than transpression along the Billefjorden Fault Zone and when much of the overburden had been reduced by erosion, most probably during Devonian time. Indeed, the original depth of rocks now exposed at the surface of the deepest zone of the western subterrane may have been about 20 or more km so representing a significant erosional event. The question has already been discussed in Chapter 12 as to what rocks within this subterrane might be proto-basement (Harland 1997). The difficulty of identifying such rocks reflects the intensity of the Silurian overprint. Indeed, the hypothesis of a proto-basement, comprising most or all of the Harkerbreen Group and below, might need extreme shearing to simulate the apparently concordant sequence and so obscure a major discordance. An alternative hypothesis supported by Russian mapping is for minor diastrophism to have occurred with little orogenic deformation, so leaving a low-angle unconformity. This conclusion was supported by Harland (1997) and in Chapter 7. The Atomfjella Complex is thus proto-basement by virtue of mild tectonism without tectogenesis between the Harkerbreen and Planetfjella groups. However this leaves major questions as to the exploration of the history within the Atomfjella Complex as discussed in Chapters 7 and 12 and not repeated here as irrelevant to the Silurian story. Nevertheless the whole of the Hecla Hoek rocks throughout Ny Friesland and Olav V Land were subject to intense Silurian tectonism. It is concluded here that whatever may be the earlier history of the Hecla Hoek geosyncline the intense Silurian sinistral transpression has somehow unified the succession. An alternative mechanism, not favoured here, for the formation of the 'Mid-Paleozoic Orogen of Svalbard' which avoided 'extremes of either lateral or vertical plate motion' was that the accumulation of vast thicknesses of sediment by 'gradual geothermal heating mobilized the less dense basement giving rise to gravitational overturn thus driving the main Mid-Paleozoic deformation and modifying the earlier metamorphic event where basement diapirism and migmatisation occurred' (Manby & Morris 1981). The westerly vergence of Ny Friesland structures matches that in Central East Greenland (e.g. Manby & Hambrey 1989).

15.3.3

Northwestern Spisbergen

Holtedahl (1914) had established the crystalline terranes of northwest. Spitsbergen as Caledonian rather than Precambrian although all the strata affected would appear to be Precambrian. It is concluded that, with the exception of the Richarddalen Complex, all other strata were not subject to any pre-Caledonian tectogenesis. Schenk (1937) outlined the structure of the Western Northwest Terrane and the most detailed study of the Smeerenburgian structures of the lower part of the Nissenfjella Formation with thicknesses of 4-5 km was by Ohta (1969) as follows. The main gneissosity has a N-S strike with a deviation of 30~ ~ to the NW-SE and all foliations dip E. Some deviations relate to the formation of the layered gneiss with concordant plagioclase-porphyroblastic granite; others suggest an open synform structure plunging SE. Refolding of S1 gneissosities was suggested from plots of synform axes. From plots of the structural data Ohta concluded that the original axes of metamorphic foliation strike N-S with gentle plunge to S and during the transformation of the gneiss to layered gneiss the schistosity was refolded in similar and drag folds, the axial surfaces of which were followed by the granite which occupies the core of the synform structures striking NW-SE and

plunging SE. The granites were thus emplaced diagonally in en echelon arrangement. This is consistent with a N-S sinistral shear motion. These structures are cut by the grey granites and then by the still later Hornemantoppen quartz-monzonite batholith. Gee & Hjelle (1966) described a similar terrane further south and higher in the succession. Strata of the Krossfjorden Group, and probably much more besides, were involved in E - W compressive - collisional and some transpressional tectogenesis in Silurian time. This caused a generally N - S lineation of folds and fabrics in the resulting rocks. Metamorphic cooling ages probably relate to these events. This tectogenesis, part of the larger Caledonide evolution, deserves a distinct label to distinguish it from the well-established Ny Friesland orogeny, which tectogenesis could then have been far distant to the south. Smeerenburgian from one of the earliest names in the region is suggested. It is then convenient to distinguish the early Smeerenburgian folding and metamorphism from the late Smeerenburgian migmatic and magmatic events. There is a significant difference in isotopic dating for these two phases. The late Smeerenburgian structures now seen at the surface must then have been at depth; but the contrast with the Ny Friesland Orogeny, which does not expose migmatites on any scale in relation to the plutons, may rather be one of stress regime in a strongly transpressive zone. Although most recent effort has been expended in identifying Precambrian thermal events sufficient data from isotopic analyses of rocks of North West Spitsbergen have been obtained to argue that metamophism may have begun (or cooled) in Silurian time through Silurian migmatic and magmatic events, and then possibly extending into earliest Devonian time. The Rb-Sr age of 414 + 20 Ma obtained for the Hornemantoppen Batholith, however suggests that the Devonian ages obtained for the surrounding metamorphic rocks may be anomalously young. Support for the Silurian age for the orogeny comes from the postulate that northwestern Spitsbergen, as part of the Caledonian orogen, was then east of North Greenland and its uplift generated the largely Llandovery westward flood of sediments over North Greenland (Hirst et al. 1983). It is likely that the broadly N-S faults, Raudfjorden and Breibogen in particular, were operating as strike-slip fault zones in Silurian time though their known history is Devonian. The possibility of the Siktefjellet Group being late Silurian would support this; but the sedimentary evidence for fault motion will be considered in the next chapter. Even the Caledonian events did not result in a significant reordering of the succession. This can be seen as folded structures, with both a broad synclinal axis, that plunge gently south into Kongsfjorden at Blomstrandhalvoya. Although the gross structure appears to be one of open upright folding (with a wave length of say 20kin) tighter mesoscopic folds occur and Hjelle (1979) observed that in the Kongsfjorden region 'three observations c. 2 k m apart, in southern Mitrahalvoya, indicate a direction of transport from east to west'. Overturned folds of 20 m wave length were reported (Hjelle 1979, p. 47). Contrasting with the above, easterly vergence is depicted in Fig. 15.5. That structure is demonstrably pre-Red Bay Group and in effect pre-Devonian. On the other hand the westerly verging structures reported above by Hjelle may be similar to the extensive evidence north of Kongsfjorden of westerly verging folds and thrusts involving Red Bay Group strata. It is therefore tentatively concluded here that the Silurian vergence was easterly and the Devonian was westerly. This conflict of opposite effects probably accounts for the difficulty in many of the metamorphic rocks of the Krossfjorden Group of establishing a clear structural history. In North East Greenland, between 75 ~ and 76~ where the main collisional Caledonian orogeny had resulted in N-S westverging fold structures, Strachan (1994) observed later E - W fold structures and mylonite gneiss which he interpreted as the result of E - W extensional collapse-thrusting in response to the earlier build up of the main orogenic welt, presumably offshore to the east. These

SILURIAN HISTORY

279

Fig. 15.5. Schematic profile of the pre-Red Bay Group structure as observed in Biskayfonna-Holtedahlfonna terrane just south of Liefdefjorden from a survey by Piepjohn & Thiedig (1992). Their profile (reversed in this figure to view from the south) clearly illustrates the easterly vergence of fold structures. structures are Late Silurian to Early Devonian. It would not contradict that hypothesis to integrate it into the ubiquitous sinistral strike-slip regime dominant at that time. In this case the collapse could be orientated according to a sinistral transtensional regime.

15.3.4

Western Svalbard

Throughout the whole of western Svalbard south of Kongsfjorden there is the problem of distinguishing Paleozoic from Cenozoic deformation because both episodes affected the area. The most obvious structures, especially as seen in the younger rocks, are Eocene yet it seems that the metamorphism and associated deformation recorded in the fabric of some rocks, was Paleozoic. In these circumstances we have to distinguish not only Cenozoic from Paleozoic and Proterozoic, but Ordovician deformation of the Eidembreen phase from Silurian and Devonian deformation. There is little doubt about the impact of the Paleogene West Spitsbergen Orogeny, of the Early to mid-Ordovician Eidembreen phase, or of a pre-Ediacaran tectonic event. The question is whether, or to what extent, Silurian (Caledonian) or Devonian (Svalbardian or Ellesmerian) tectonism affected these western terranes. Criteria for such distinctions have been attempted by more than one person but with little success. The West Spitsbergen Orogen generally divides into two p a r t s - a western belt of pre-Cambrian rocks (always lacking Devonian) and an eastern belt of very clearly displayed postDevonian strata, which admirably exhibits the Paleogene structures. Until recently there was little chance of interpreting the preCarboniferous structures because that stratigraphy was often quite uncertain. Some of the interpretation of Harland, Hambrey & Waddams (1993) with regard to the extensive Vendian strata makes it feasible to begin to unravel the earlier story. Two (apparently conflicting) groups of observations need consideration. (i) On both sides of Forlandsundet the Varanger diamictites show flattened and elongated stones consistent with a N-S shear zone in some instances sinistral. The metamorphic facies in these rocks would seem to belong to that phase which bears little in common with the Eocene tectogenesis. Also, especially in the southwest corner of Daudmannsodden are dolostone and limestone marbles intensely sheared in a N-S direction with near-vertical foliation and unmistakeable sinistral small-scale isoclinal folds. These observations suggest that zones of shearing of Silurian or Devonian transpression could have been the dominant deformation. A Devonian age may be favoured if the deformation is limited to locations near the terrane margins. (ii) Not easily fitted to the above concept are the observations where strata are seen to be dipping almost vertically resulting from the Paleocene Orogeny but without noticeable Paleozoic angular unconformity. This is a vertical concordant unconformity with Early Paleocene strata resting on ?Silurian strata (on the northern coast of Prins Karls Forland). Elsewhere, especially near the mouth of

Eidembreen (e.g. at Farmhamna), Varanger strata, also vertical, are concordantly in contact (?unconformably) with Carboniferous strata. At both these occurrences the earlier strata were not significantly deformed until Eocene time. But these are isolated and distant occurrences and a systematic structural study based on the pre-Devonian stratigraphy is needed. Indeed it seems that there is no case in the Western Terranes where a post-Silurian-preCarboniferous angular unconformity can be clearly demonstrated. From analyses of structures north and south of St Jonsfjorden in western Oscar II Land, Morris (1988) and Ratliff et al. (1988) identified two levels of deformations. The lower in the Vendian strata showed E - W compression with easterly vergence and the upper in Paleozoic strata with N N E vergence and dextral strike-slip followed by E - W compression with easterly vergence. Because these structures were not evident in a Carboniferous sandstone slice to the west it was concluded that these structures were Caledonian. On the other hand the sandstones are competent and the structures fit the dextral transpressive regime of the West Spitsbergen Orogeny during which the Carboniferous rocks were emplaced so that a Paleogene age for these structures cannot be ruled out, and is preferred here. Nordenski61dkysten, south of Isfjorden provides the only extensive unfaulted unconformity of Early Carboniferous on preSilurian (probably Vendian) strata. The contact is steep, often vertical. The 1:100 000 maps B9G and B10G (Ohta et al. 1991) and Hjelle et al. (1985) decisively demonstrate overstep of successive older strata. Therefore there is a post-Vendian/pre-Tournaisian tectonic episode. By comparison with other west coast geology a Silurian diastrophism seems less likely than an Ordovician (Eidembreen episode) or a Devonian (Early Ellesmerian) timing, because of the Silurian sedimentary record. In conclusion the Western Terranes are not classified here with the typical Silurian Caledonian tectogenesis of the Central and Eastern Terranes.

15.3.5

Southwestern Spitsbergen (Wedel Jarlsberg Land)

Wedel Jarlsberg Land west of the postulated RecherchebreenHansbreen Fault contains two deformed areas of the Protobasement having been subject to pre-Vendian tectonism. According to the interpretation here (e.g. Chapter 10), the Proterozoic cover rocks are largely Vendian. They display broad-open folding with little penetrative deformation except in the less competent strata which could result as well from Paleogene as from Paleozoic deformation. Paleogene strain is virtually certain so that a case needs to be made for a Paleozoic tectonic episode in addition.

15.3.6

Southern Spitsbergen

The best impression of the structure of southern Spitsbergen, east of the N-S Hansbreen Fault, may be obtained from the two composite profiles north and south of Hornsund prepared for the International Geological Congress in 1960 by Birkenmajer

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CHAPTER 15

(Fig. 10.10). Superficially there is a systematic westerly dip of folded strata and thrust faults. Some of the older rocks have been overfolded and the succession inverted. For example the G{tshamna (phyllite) Formation dips to the west beneath older strata. However, a closer look reveals a distinct contrast between the structures east and west of a line running through eastern Burgerbukta to the north and Samarinv~tgen to the south. To the west and south of Hornsund, structures as described above are truncated and overlain unconformably by flatlying Early Triassic strata. The underlying rocks are of pre-Vendian, Vendian and Cambrian to Early Ordovician age. The stratigraphic gap for this deformation is thus, mid-Ordovician through Permian. To the east of the line the structures are seen in Devonian through Cretaceous and (further east) Paleogene rocks. These are typical of the eastward-verging Eocene fold and thrust belt of the West Spitsbergen Orogeny. Both east and west of this belt of conspicuous deformation are only younger rocks. Their complex history will be discussed in later chapters. The pre-Triassic core structure of folded and thrust preDevonian strata is our concern here as potentially the product of Caledonian deformation of possible/probable Silurian age. Inspection of the draft Torellbreen Geological 1:100 000 sheet shows that most critical contacts between the Devonian Marietoppen Formation and the Ordovician or older strata appear to be faulted. Nevertheless in an area of many thrust slices so much proximity between the older and younger strata suggests that originally a sedimentary mid-Ordovician to Early Devonian break represents the Caledonian deformation of the core belt. The juxtaposition of two structural belts of similar appearance and no obvious discontinuity (i.e. the core belt deforming preSilurian strata and the eastern belt deforming all post-Silurian strata) must raise a question. It would be easy to account for the whole structure as Eocene deformation were it not for outliers of Triassic strata truncating the western core structure and seen only south of Hornsund. This contact is shown as an unconformity on the Sorkapp sheet C13G (Winsnes et al. 1992) and in Birkenmajer's (1960) profile south of Hornsund. If the outliers were klippen then the whole orogen could be Eocene, but the evidence (including our own observations) appears to be against it. Currently we must take it that the core western structure has been thrust over the eastern in the Eocene West Spitsbergen Orogeny. In conclusion, the solution adopted here is that the middle Hornsund structures both to the south and the north are Silurian (Caledonian)-verging eastwards and are followed by Eocene eastward-verging thrusts.

15.3.7

Bjornoya

The very small outcrop, in the southeast of Bjornoya, shows westward-verging deformation in which the incompetent Sorhamna Formation has played a part. The overlying and underlying carbonate formations have behaved competently and give little evidence of tectonic history. Nevertheless the whole deformation is post-Caradoc and pre-Latest Devonian and so may fairly be taken as part of the Caledonian folded zone. The unconformity between the Ymerdalen and the Sorhamna formations does not represent a major tectogenesis, rather (more probably) uplift, erosion and penetration of the eroded surface by sediments.

15.3.8 Summary of tectonic vergences The vergence of folding and thrusting may be related to the palinspastic hypothesis. The four provinces are summarized in Section 14.5.1 and illustrated in Figure 14.10. (i) Folding in Ny Friesland and Nordaustlandet is either upright or in the west verges westwards in conformity with its proximity to the Caledonian front in East Greenland.

(ii) In the central terranes there are two situations. (a) In the south, where deformation can be certainly constrained between Canadian and Triassic, and probably preDevonian, vergence is clearly to the east. The difficulty is that the later West Spitsbergen Orogen also verges eastwards. (b) In the northwest of Spitsbergen pre-Devonian vergence is also clearly to the east (Piepjohn & Thieding 1992) whereas later Devonian vergence is westerly. The above suggests that these central Spitsbergen terranes represent the easterly belt of the North East Greenland Caledonides which otherwise is not known. (i) and (ii) above thus must have been separately deformed in a Silurian collisional orogeny before the sinistral strike-slip component juxtaposed them. (iii) Bjornoya Caledonian deformation is manifestly westerly and is consistent with its conjectured location near the northwestern margin of the Caledonides. (iv) As already argued the western terranes probably escaped involvement in major Silurian tectogenesis, but rather received some debris flowing westerly from the Caledonian front.

15.4

Silurian petrogenesis of crystalline rocks

Crystalline outcrops are a dominant feature of the Silurian orogenic development of Svalbard. These may be described as orthotectonic terranes in contrast to the largely unmetamorphosed stratified terranes of sedimentary rocks. The genesis of some of the crystalline rocks merits further consideration. Because of the uncertainty as to the protolith of some metamorphic bodies, Bayly's (1957) classification of Ny Friesland rocks using the terminology of (Wallis et al. 1968, 1969) is followed. It was designed to avoid prejudging the origins of the rocks in question. This was a classification according to whether more than 50% of the rock was composed of specified minerals or a mineral composition group. The common metasedimentary classes were psammite (50-80% quartz) with the exceptional quartzite (80-100% quartz), pelite for >50% of alumino silicates, marble for >50% carbonates. Difficult classes were feidspathite for >50% feldspar and 'amphibolite' for >50 mafics (amphibolites and pyroxenes) because of their uncertain genesis. However, the following summary begins with the account of the development of the crystalline terrane of northwestern Spitsbergen whose petrogenesis is somewhat easier to understand because it was not subject to such intense shearing as in Ny Friesland and has been more accessible for study than the eastern terranes of Nordaustlandet. The consideration of three different kinds of granite and of amphibolite banding concludes this section; the later discussions being of early petrogenetic problems.

15.4.1

Metamorphism of sedimentary rocks

Northwest Spitsbergen. The total thickness of sediments is a pertinent consideration. At the southern part of the crystalline terrane a stratigraphy of three formations has been established totalling more than 4 kin. In the north, in the lower strata of the lower formation in the western part of Vasahalvoya (the extreme NW corner), a thickness of 5200 m of metasediments was estimated. Probably 7 or 8 km of original strata are now evident in this terrane. Moreover, most of the original strata now exposed have been metamorphosed to a high grade suggesting that perhaps another five or more km of overlying strata (increased to say 10 km by folding) was sufficient overburden and has subsequently been removed, much of it eroded in Silurian through Devonian time. Marbles. The carbonate sediments are perhaps the most conspicuous and the most resistant to alteration. Marbles vary between those with marked fractures and those transitional to plastic deformation. The strata are commonly boudinaged and the marbles show the greatest tendency to

SILURIAN HISTORY retain their shape in contrast to the more siliceous layers. These are accompanied by skarns rich in diopside, wollastonite, vesuvianite and grossularite with some scapolite, titanite and hematite. Frequently amphibolites are found in the variety of marble bands. Some migmatites suggest evidence of amphibolitisation of marble. Pelites. Phyllites are common in the higher horizons in which chloritoid may occur with quartz-muscovite-quartz compositions. Mica-schists are more typical in muscovite-biotite-quartz assemblages with chlorite and plagioclase, and usually with garnet. Two generations of biotite can be distinguished- the older being somewhat chloritized. The feldspars are sodic plagioclases and the newly formed feldspars increase conspicuously from south to north; where the migmatitic development is more general. Psammites and quartzites. These quartz-rich rocks are less abundant but are easily recognized. Amphibolites, marking an igneous component, are common in the lower strata and generally show little alteration from a basite composition.

Western Ny Friesland. Bayly (1957) described the lower Hecla Hoek strata in six petrographic groups according to composition (a) pink quartzite, (b) variable quartzite, (c) granite gneiss (d) calcschists (with some pure marbles), (e) feldspathic schist (f) amphibolite. He also distinguished five metamorphic facies: a chlorite zone which extended in places eastwards into the middle Hecla Hoek as did a biotite zone to the west. An albite-epidote-amphibolite facies which extended along the east and western flanks of the Atomfjella Arch, the arch itself being characterised by amphibolite facies much of it in the staurolite-kyanite sub-facies. The protoliths of the granitic gneiss and amphibolite are discussed in sections 15.4.7 and 15.4.10. Bayly commented on the relationship between several facies and depth in the orogen. The strata in the amphibolite facies would have been 13 to 15 km deep in the stratal pile even before tectonic thickening so that the orogenic thickening less contemporary erosion could have achieved greater tectonic depth. Gayer et al. (1966) surveyed available isotopic ages in Svalbard including those for Ny Friesland metamorphics.

15.4.2

Layered gneiss

Northwest Spitsbergen. Layered gneiss is mainly of pelitic composition and lies between mica-schists with beds of quartzite, and migmatite. Sporadic lenses and pockets of igneous-textured feldspar-rich rocks, sometimes occur in the mica schist as forerunners to the layered gneiss. Plagioclase porphyroblasts developed later. Some granitic layers are evidently feldspathised beds of primary impure quartzites, with alternations of layered gneiss and migmatite representing original stratal lithologies (Hjelle 1979). Schumacher, Ohta & Bucher (1995) reported that 429-437 Ma (Early Silurian) metamorphism in aluminous gneisses had generated polycrystalline segregations of green spinel and corundum enclosed in a corona of cordierite which separated them from the matrix of plagioclase and biotite. Sillimanite was suggested as a likely precursor. Possible mineral reactions were offered for the origin of cordierite in these associations in a post-peak uplift decompressive environment. Ohta (1969) described the first stage in the transformation from fine-grained banded gneiss to layered gneiss as the appearance of isolated plagioclase porphyroblasts. These occur first in the compositionally intermediate layer between pelites and psammites, then in the pelites and last in the psammites. Gneiss comprises felsic and mafic layers which are commonly boudinaged. Some felsic layers are evidently mobilised, with penetration of granitic material. The mafic layers are often entirely enclosed by granitic materials (Hjelle 1979).

and the layered gneiss grade into migmatites with ptygmatic granite veins. As mobility increases away from the gneiss, the migmatite metaster loses orientation related to earlier structures and the compositional banding becomes more diffuse' (Hjelle 1979, p. 51). Four compositional groups of migmatites were recognized: pelitic (the most common), psammitic, calcareous and amphibolitic. Amphibolite masses are frequently found near marble bands giving evidence of amphibolitization and induced foliation prior to migmatization. Metasters show progressive assimilation from agmatitic to streaky and nebulitic migmatite beginning with injection and ending with ghost granites. Amphibolites and marbles show least alteration. The ultimate metatect shows great variation in composition yet averaging that of granite or granodiorite. The apparent change from pelitic metasediments retains quartz at 25-30%, greatly increases K-feldspar, reduces plagioclase which becomes more rich in soda and greatly reduces biotite and other pelitic minerals. The above account summarizes that given by Hjelle (1979, pp. 57-62).

15.4.4

Granites

The most thorough study of granites in Svalbard (with a review of earlier work) was by Hjelle (1966) (Fig. 15.6). Granites in four areas were investigated for their modal and approximate chemical compositions: Northwest Spitsbergen, Central Ny Friesland in northeast Spitsbergen; and in Nordaustlandet: Laponiahalvoya to Nordkapp in the northwest and Central Nordaustlandet. His classification with quartz > 10% was by feldspar volume as shown in Fig. 15.6 taken from Hjelle (1966) so defining 8 rock species: 1, trondhjemite; 2, Na-granite; 3, normal granodiorite; 4, K-granite; 5, granosyenite; 6, quartz monzonite; 7, granodiorite; 8, quartz diorite (Fig. 15.6). His detailed mineralogical and chemical results are not repeated here. Hjelle (1966) recognized three main types of granites. (i) Medium-grained grey granite to quartz diorite in northwest Spitsbergen, often occurring as dyke rocks in the migmatites. These are the syntectonic layered granites of most authors. They are generally younger than the migmatites and older than the massive pink unfoliated granites. (ii) Coarse, often porphyritic, mainly quartz monzonites. They generally occur as batholiths in N W Spitsbergen and central Ny Friesland. (iii) Medium-grained granites of the Nordkapp area of northernmost west Nordaustlandet and of Laponiahalvoya and Rijpfjorden-Rijpdalen, in northwestern and central Nordaustlandet respectively.

An

An

\

Ab

15.4.3

281

25

45

65

K feldspar

Migmatites

'When the degree of feldspathisation and mobilisation increases in the layered gneiss, the granitic material begins to penetrate discordantly the layers and the axial planes of the small folds discordantly,

Fig. 15.6. Quantitative petrographical classification of granitic rocks in Svalbard. Quartz >10vol%, Feldspars >30vo1% (as used by Hjelle 1966).

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(iv) To the above three classes of Hjelle, the 'feldspathites' of N y Friesland are distinguished. They were so designated because of their p r o b l e m a t i c history and genesis in western N y Friesland ( H a r l a n d , Wallis & G a y e r 1966). To anticipate the following discussion (i) and (ii) above are confirmed as Paleozoic a n d related to the C a l e d o n i a n o r o g e n y whereas (iii) and (iv) are n o w confirmed as originally Proterozoic but modified by mid-Paleozoic t e c t o n o - t h e r m a l influence.

15.4.5

Syntectonic (grey) granites

Grey, often foliated, granites are typical of the extreme n o r t h w e s t e r n and n o r t h e a s t e r n terranes of Svalbard. They are typically closely associated with migmatites. F r o m the northwest, e.g. in V a s a h a l v o y a the w o r k of O h t a a n d of Gjelsvik was described by Hjelle (1979) a n d integrated with that of Gee (Gee & Hjelle 1966). Marginal contacts are gradational, but some truncate earlier structures. Some contain shadowy metasters with the implication that the granitic magmas represented a more advanced stage in the process of migmatization. That is to say that they are dominantly metatect with only occasional ghost metaster relicts. All grey granites adjoin migmatite areas. The composition (typically monzo-granite to quartz diorite) corresponds to the bulk composition of the migmatites. Structurally the granitic rocks conform to the flow structures of the open folding of the migmatites rather than the older tight isoclinal folding of the gneisses. Associated with these occurrences are grey-granitic dyke rocks of two generations. The earlier intrusive relationships reflect an early stage in the penetration of the metaster, i.e. early to pre-migmatite. Later more common dykes cut across the migmatites (with sharp contacts). They often follow the jointing. These dykes also include aplitic and pegmatitic facies, the latter are generally younger and narrower (only 10% > 0.5 m). Again the composition is typically monzo-granite to granodiorite. The migmatites and then the granites represent the Early through Late Smeerenburgian phases. Indeed Hjelle (1966) recognized two main periods of intrusion. (1) One earlier, relatively deep-seated and related to the migmatization; the structures were folded in the orogeny and discussed in Section 15.4.3 above. (2) The second which is Hjelle's class (i) cuts the migmatite gneisses and metasediments as dykes. The dyke widths are typically less than I m but may range up to 2 km east of Krossfjorden. As a result of assimilation the compositions are variable with quartz monzonite, granodiorite and quartz diorite predominating. In Nordaustlandet, the grey granite-red granite contrast was noted by Sandford (1926), but at a time when migmatization was not a familiar concept, although the term migmatite is an old one. Silurian or Devonian tectono-thermal overprint on demonstrably Proterozoic original granites (as well as the host rocks) as have been identified by age determinations of zircons. To what extent a Silurian-Devonian rejuvenation of a Proterozoic magmatic terrane was general remains to be elucidated. Isotopic age determination of these grey granites are few but they must be older than the late tectonic plutons referred to below.

15.4.6

Late tectonic plutons

Late tectonic batholiths are distinctive bodies generally of pink porphyritic granite lacking any foliation. The H o r n e m a n n t o p p e n Batholith occupies the n o r t h w e s t e r n Spitsbergen terrane. In eastern N y Friesland are two m a i n batholiths, C h y d e n i u s b r e e n and Nordenski61dbreen. Their names imply relatively p o o r exposure. In N o r d a u s t l a n d e t there are m o r e plutons of less regular o u t c r o p pattern, which is itself obscured by ice or sea. They m a y not all be large e n o u g h to qualify as batholiths. The occurrences were m a p p e d at I : I M (Winsnes 1986) b o t h east a n d west of L a p o n i a h a l v o y a and M a r t e n s o y a , east and south of Rijpfjorden, a n d three units in a n d near D u v e f j o r d e n . H o w e v e r , the N o r d a u s tlandet plutons are m o r e p r o b a b l y N e o p r o t e r o z o i c , nevertheless they a p p e a r to have been reheated in Silurian to D e v o n i a n time f r o m K - A r age determinations.

Northwest Spitsbergen. The Hornemantoppen Batholith (Hjelle 1979) occurs within the migmatite terrane and covers 150km 2. Of the varied facies is a coarse to medium grained red monzo-granite grading with equal proportions of potash and plagioclase feldspars (c. 60%), the former reaching 2cm in porphyritic varieties. Then after quartz (c. 30%), biotite constitutes 4-8% with some chlorite and plagioclase tending to sericite, accessories are titanite, apatite, pyrite and magnetite. The latter is more abundant than in the migmatites and is sufficiently abundant to cause a magnetic anomaly which may suggest a basic facies lower in the pluton. The granite is cut by aplites and pegmatites and contains small xenoliths. Marginal foliation suggests a batholithic shape as does a relief of 700 m. The granite contacts are unsheared, intrusive and truncate the migmatite structures which entirely surround it. No hornfelsing was observed. Part of the roof zone in the north may be seen with roof pendants and larger xenoliths. The batholith may either have been emplaced in a pre-existing antiform or, more likely, to have itself arched the country rock structures (Hjelle 1979). Hjelle reported a whole rock Rb-Sr age of 414Ma (approximately Late Silurian to Early Devonian). The composition given by Hjelle (1966) is of quartz-monzonite. Balashov et al. (1996)obtained a Rb-Sr age of 413 + 5 Ma. Ny Friesland. The Chydeniusbreen Granite Batholith. The Chydeniusbreen Granite occurs entirely within the middle Hecla Hoek strata of the Lomfjorden Supergroup. They are folded but not obviously metamorphosed except for a one km wide zone of hornfels. Most of the main outcrop is covered by ice but the granite supports Newtontoppen the highest (ice) peak of Svalbard at 1717m. The batholith appears as a diapiric emplacement having shouldered its way through the country rock when its margins at least were already solidified. It is difficult to say whether the marked attenuation of steeply dipping strata, especially on the west side, was the result of the emplacement or of simultaneous or late E-W compression of the orogen. Both may have operated. The rock is described briefly in Chapter 7.4 (Harland 1959). It averaged granite-adamellite and varies locally, partly according to border (xenolithic contamination) facies. Hjelle (1966) remarked on the uniform composition classifying it as quartz monzonite to granosyenite. K-Ar ages of the granite biotite yielded 391,395 and 414 Ma, say 400 Ma, at or later than the Silurian Devonian boundary (Hamilton et al. 1962). A further small outcrop the Raudfjorden granite crops out to the north east and appears to be an apophysis of the main body. Indeed there may well be a connexion between these granites at no great depth (Harland 1959). These granites have been described in much greater detail (Teben'kov et al. 1996), but with little change to the above conclusions (Section 7.4.1) and concluded an age of 432 + 10 Ma. The Nordenskiiildbreen Batholith. Tyrrell (1922) described a syenitic suite from morainic samples. These were derived from what appears to be an extensive subglacial outcrop seen in the cliffs of the nunataks of Terrierfjellet and Ferrierfjellet. These nunataks show that the unconformable Carboniferous cover would project beneath the surface of the ice field of Lomonosovfanna and the syenitic rocks evident in the marginal exposures may not be typical of the whole batholith. The samples described held more quartz and less augite than a typical syenite Hjelle (1966). It was suggested ( H a r l a n d 1971) that the c o m b i n e d effect of tectonic thickening with increased o v e r b u r d e n of the lower rocks, c o m b i n e d with the shear friction in the neighbouring zone of transpression increased the t e m p e r a t u r e so as to generate m a g m a from the lower Hecla H o e k rocks. That the m a g m a penetrated the overlying strata to the side o f the m a i n orthotectonic zone might be due to the lack of the space in the pervasive transpressive regime in contrast to the contiguous unsheared c o m p e t e n t terrane which could have generated space for the initial diapirs by the adjacent N - S extensive regime.

The Nordaustlandet granite plutons.

S a n d f o r d (1926) perhaps first suggested a C a l e d o n i a n age for the granites of N o r d a u s t l a n d e t as confirmed subsequently. The various outcrops m a y be grouped into two principal areas (Hjelle in F l o o d e t al. 1969). (i) In the northwest at L a p o n i a h a l v o y a and (ii) R i j p f j o r d e n - R i j p d a l e n , further east. The m o s t frequently observed mineralogical association in the granites is q u a r t z - m i c r o c l i n e - p l a g i o c l a s e (albiteoligoclase)-biotite-muscovite. This suggest a m o r e alkaline and less calcic and r e m i t c o m p o s i t i o n t h a n that of N y Friesland.

SILURIAN HISTORY Hjelle (1966) remarked that the two principal granites of Nordaustlandet (i) and (ii) below are similar not only in composition, but in many other respects (refer to Section 6.4 for details). They are medium-grained, leucocratic, muscovite granites. However, it is now virtually certain that in spite of Phanerozoic ages the Laponiahalvoya granites are at least Neoproterozoic and by analogy also those further east. The following summarizes the isotopic age data, discussed in Section 6.4, for the Nordaustlandet granites. (i) The Laponianhalvoya granites show a variation in isotopic ages, with K - A r dating suggesting an age range of Mid-Silurian to Early Devonian (Krasil'shchikov et al. 1964). However, zircon ages from the Kontaktberget and Laponiafjellet granites gave ages of 939 • 8 and 961 + 17 Ma respectively (Gee et al. 1995). The Nordkapp granite has only one Rb-Sr date of 537 Ma (Hamilton & Sandford 1964), and its significance is open to interpretation. (ii) The Rijpfjorden-Rijpdalen granites also appear to show definite Silurian-Devonian ages (Krasil'shchikov et al. 1964), although Gee & Teben'kov (1996) suggest a 'Grenvillian' age based on a zircon date.

15.4.7

15.4.8

283

Feldspathic (augen) schists

Ny Friesland. Whereas many of the stratiform feldspathites exhibit feldspar augen textures, it is the Planetfjella Group schists that are especially noteworthy in this respect. This distinctive facies extends the entire length of Ny Friesland west of the Veteranen Line. Harland & Wilson (1956, p.275) described these Planetfjella schists with 'conspicuous pink feldspar augen set in a dark schistose matrix'. Bayly (1957, p.387) wrote 'the dominant textural feature is a lozenge-shaped feldspar clot, but this is usually not a true auge: that is to say, there is no central crystal which has forced an opening in the foliation and produced vacancies on either side of it'. The clots are homogenous aggregates. The other minerals evident are biotite, garnet, tourmaline, clinozoisite and occasional fluorite and allanite. Wallis (1966) described the stratigraphy and petrology of the group in more detail. The feldspathic lithology is best seen in the F1Aen Formation (the lower of the two in the group) divisions (4), (6), (7) and (8) contain the feldspar megacrysts. They were interpreted as derivatives of acid pyroclastics or arkoses but the exact genesis was not clear (Harland et al. 1966). The intense shearing is however consistent with the sinistral transpression structure of the whole of western Ny Friesland (Harland 1971) (see model in Fig. 15.4).

Stratiform feldspathites

Ny Friesland. It was primarily because of the puzzling nature of these granitoid rocks that the classification of feldspathites having >50% feldspar was applied (Wallis et al. 1968, 1969). The principal such unit occurs in the Harkerbreen Group as the Bangenhuk Formation, a granite gneiss in the north correlated with the original Camryggen gneiss in the south of western Ny Friesland (Bayly 1957; Harland, Wallis & Gayer 1966; Harland et al. 1992). Structurally this unit is exposed as a stratiform body at least 120 km N-S, up to 20 km E - W and up to 2 km thick. It occurs in a consistent sequental relationship to meta-strata above and below. Some margins show graded compositions with growth of feldspar phenoblasts in adjacent metasediments. In south Spitsbergen a thinner Bottfjellet band, stratigraphically a little higher than the Camryggen gneiss shows similar transitional margins. These characteristics led Harland et al. (1966) to account also for its typical granitic composition and occasional intrusive contacts by suggesting that it was formed as arkose or more likely as ignimbite sheets. Later tectogenesis would produce its spindle-shaped gneissose texture and thermal metamorphism, and would melt it locally so as to produce the intrusive effects. Others have argued that the rock body is a typical granite of magmatic origin in which case a sill or a laccolith may be envisaged. This opinion is strongly supported by the primary nature of the zircon crystals whose ages approximate 1750 Ma (Gee et al. 1992; Johansson et al. 1995; Chapter 12). The other two of the metasedimentary units into which the granite was supposed to have intruded turned out to be much younger so in these cases the granite was reinterpreted as basement, leaving one host formation which might be older (Gee 1996). Whatever the origin of the Bangenhuk granitoid it could not have been emplaced except tectonically within large nappes or thrust sheets. In any case intense Caledonian tectonism has modified its original nature, shearing it to spindle-form gneissose texture. The magmatic contacts could then be either relicts of its original nature or the effect of subsequent melting. Because of its remarkable nature the rock body has attracted considerable attention structurally, isotopically and geochemically. It retains through Ny Friesland a consistent stratigraphic position. There is no doubt about the mid-Silurian age of its deformation and metamorphism. However, the zircon studies of Johansson et al. (1995) made it certain that there was a late Paleoproterozoic magmatic origin or zircon component. The problem remains as to how this thin extended sheet would appear on a large scale map. A somewhat similar granitic feldspathite has been mapped in northernmost Ny Friesland at a lower level, introducing a new (Instrumentberget) unit at the base of the Harkerbreen Group (Johansson et al. 1995). The same considerations may apply.

15.4.9

Shear zones and mylonites

Ny Friesland. The upper (Vildadalen) formation of the Planetfjella Group is largely a chlorite-biotite sub-pelite and its (upper) Ros6nfjella Member, 1500m suffered intense two-phase deformation with minor folds in the hinges of earlier folds. The finegrained psammitic interlayers recrystallized as quartz lenses which are a distinctive feature of the pelitic facies of the Planetfjella Group (Wallis 1966). This facies, often with near-vertical N-S, foliation forms what Manby & Lyberis (1995) have referred to as the Eolusletta Shear Zone. Within it are mylonitic zones as noted by Manby (1990) Mylonites, concordant with the general foliation, are evident on the northwestern coast of Ny Friesland within the Harkerbreen Group as a 'zone of retrograde greenschist facies rocks, mylonites and related ductile-brittle shearing phenomena, indicating a long history of sinistral displacement in the Hecla Hoek parallel to the Billefjorden Fault Zone (Manby & Harland unpublished paper)' (Manby 1990, p. 132). At the southwest margin of Ny Friesland, where Hecla Hoek rocks adjoin the Billefjorden Fault Zone on land and overthrust the Devonian rocks to the west, is a 2-3 km wide chlorite zone (the Cambridgebreen Sheer Zone) almost certainly retrograded from Harkerbreen Group amphibolites. The brittle fracture in this zone indicates shear under a shallower overburden and is taken to represent much of the Devonian strike-slip component. This is a shear zone of mafic rather than feldspathic rocks and thus relates to the following subsection.

15.4.10

Mafites

Ny Friesland. In the tectonic environments of the Silurian orogeny amphibolites are the typical mafic facies. In Ny Friesland it had been concluded (Harland 1959; Harland, Wallis & Gayer 1966; Harland et al. 1992) that the basic layers which are common within the Harkerbreen Group, but not in the overlying Planetfjella Group, and rare in the underlying Smutsbreen Formation of the Finnlandveggen Group, were mainly contemporaneous or penecontemporaneous with the associated strata. The principal lithology is of amphibolite schists and gneiss. Excluded from this immediate discussion are some massive basites with preserved igneous (ophitic) texture. The opinion for a penecontemporaneous origin was that not only do amphibolites occur, most conspicuously as concordant black

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layers within pale coloured quartzite, but that black bands only a few m m thick extend systematically over considerable distances. The boundaries are seen to be sometimes sharp and sometimes transitional. The interpretation is that basic volcanic activity was prevalent with both lava and pyroclastic eruptions. In such a volcanic environment some transgressive sills and feeder dykes might be expected. Indeed, some cross-cutting bodies are observed. Different viewpoints had also been expressed. Harland (1941) suggested lit-par-lit intrusions. Manby (1990) argued that the amphibolites were not contemporaneous nor penecontemporaneous but were later igneous bodies. These alternative ideas would need to be accommodated according to the evident extreme transpression in the stratification in which nearly all originally discordant structures would now appear to be concordant, and the thin bands would originally have been thicker. In the less extreme alteration, however, the competent amphibolite bands are commonly boudinaged within the quartz-rich strata, always extending N-S. The basic rocks with igneous texture range from quartz-dolerites to quartz augite macro-norites (Manby 1990) and some with primary biotite and hornblende and olivine hypersthene dolerites were reported (Gayer 1969). Manby (1990) gave detailed mineral and chemical details which confirm that they derived from basaltic rocks with marginal calc-alkaline to tholeiite compositions in a related magmatic suite which would be consistent with a variety of tectonic environments. The critical point for Silurian history is that if the mafic rocks formed only at one time it would have been in a contemporary Proterozoic episode. But if the intrusive basites were later that event could be Proterozoic or Paleozoic, and if the latter most probably connected with the Silurian Ny Friesland Orogeny. The model for such a Silurian event might be a temporary transtensional phase during the main orogenic compression rather than a reversal from compression to extension. A Proterozoic origin for most sheets is virtually certain. A Silurian origin for some bodies remains to be established.

15.5 15.5.1

Silurian terranes, provinces and palinspastics Grouping of terranes by province

The foregoing discussions are now reviewed according to the hypothetical model of allochthonous terranes in which those with affinities are grouped together as parts of four original provinces. These were provinces on the margins of Laurentia. Three were dismembered largely through Silurian displacements. The fourth (southern) Bjornoya Terrane was probably deformed east of the westward-verging North Greenland Caledonides and may have remained attached to Eastern North Greenland until severed from it by Paleogene dextral faulting to form part of the composite Svalbard terrane and indeed part of the Barents shelf at the northeast corner of Eurasia (Smith in press). The evidence for the original (provincial) relationship of the terranes belongs mainly to late Proterozoic and early Paleozoic stratigraphy and tectonics. The final juxtaposition or docking of the displaced terranes to form the composite terrane of most of Svalbard was completed in Devonian time. The Silurian story of tectogenesis is the reflection of the active displacement of these terranes following the closing of the Iapetus Ocean (mainly in Ordovician time); the initial collision tectonics was followed by large zones of transpression as some Svalbard terranes moved north with respect to Greenland. In turn transpression changed to transcurrence as the strike-slip component replaced the convergent motion between the newly consolidating Caledonides on the margins of a Barents Craton and Baltica. The terranes and their present bounding fault zones are listed below as introduced in Chapter 3. What is observed today in each terrane is a distinct tectonostratigraphic sequence and configuration through Neoproterozoic, Cambrian and Ordovician time, with Silurian (and later) tectogenesis superimposed.

The western terranes contrast with the others in that sedimentation reflects a mobile tectonic environment which persisted at least Vendian through Silurian time with a marked Early to midOrdovician (Eidembreen) tectonic episode. The Central and Eastern terranes were relatively stable until the Early Silurian Caledonian Orogeny, with stable sedimentary environments where sediments may be exceptionally preserved. Because of a possible confusion between the individual descriptive terranes, each in the singular, and their hypothetical grouping into Eastern, Central, Western and Bjornoya terranes the term province, as first used by Harland & Wright (1979), is employed to distinguish the palinspastic interpretation from the descriptive units. Thus, the eastern terranes: (a) i-vi below, are referred to as the Eastern Province and derived from the Central East Greenland Province.

(a) The Eastern Province of Svalbard. Much has been already made of the affinity of the east Svalbard pre-Devonian successions and those of Central East Greenland and it is taken here that these East Svalbard Terranes once formed part of the East Greenland Province.

(i) Nordaustlandet Eastern Terrane (NAET). Originally thought to be a Precambrian metamorphic terrane it was then reinterpreted as part of the Caledonian orogen in which the Precambrian metasedimentary strata and underlying migmatites would be the result of Silurian tectonothermal events. Isotopic ages now throw doubt on either model in its simple form. Late Precambrian values around 600 Ma and older zircons indicate earlier events of unknown age because later values ranging from 438 to 373 Ma indicate Llandovery through Mid-Devonian ages. In this terrane, the meta-sedimentary succession is relatively flat-lying implying that the Phanerozoic events were dominantly thermal rather than tectogenic. The later thermal influence was mainly Devonian. It is discussed in the next chapter as part of the 'Lomonosov conjecture'. NAET may be accepted, as long advocated by Russian geologists, as part of the Barents Craton (north of Iapetus) and the eastern foreland of the Ny Friesland Orogen. (ii) Nordaustlandet Western Terrane (NAWT). This terrane west of Rijpfjorden is better known and has a distinct Precambrian Hecla Hoek stratal succession with magmatic events around 970 Ma from zircons but also with Silurian-Devonian ages. The latter are related to the Ny Friesland (Caledonian) orogeny which folded the strata in a broad southwardplunging anticline with axes on the Laponianhalvoya granites. Further west in the Murchisonfjorden region the Neoproterozoic strata (which young westwards) are steeply folded on N-S axes forming the eastern limb of the Hinlopenstretet Synclinorium. No major fault or shear zone has been established separating these terranes within Nordaustlandet or in Hinlopenstretet even though the whole area is traversed by faults. NAWT is thus a continuation of NFET. (iii) Ny Friesland Eastern Terrane (NFET). This terrane constitutes the western limb of the Hinlopenstretet Synclinorium exposing the youngest Hecla Hoek strata (Llanvirn) on the eastern coastline and the oldest of the middle Hecla Hoek Veteranen strata at the Veteranen Line on the west. The strata are penetrated by three late tectonic batholiths with (limited) age data spanning the Silurian-Devonian boundary. The strata are strongly deformed in upright folds and with pinched synclines of low competence (Vendian) strata to the east all with N-S axes and with a regional dip to the east. The folding, defining the Ny Friesland orogeny, is demonstrably postLlanvirn and pre-Devonian, presumed to be mainly Silurian. Metamorphism to chlorite grade is evident in the north especially within the Vendian pelites, whereas most strata are competent carbonates, quartzites or psammites and the style indicates a deep fold structure. The only evidence for N-S stretching evident in the east might be the emplacement of the batholiths. (iv) Ny Friesland Western Terrane (NFWT). West of the Veteranen Line and the east of the Billefjorden Fault Zone is the Lower Hecla Hoek complex (Stubendorffbreen Supergroup) of three groups of rocks, all intensely metamorphosed. The tectogenesis is all clearly part of the same Ny Friesland Orogeny. Thanks to the metamorphism the age of the principal tectonothermal events was reported in 1966 spanning the Silurian Period and then, with more sophisticated determinations, was reported in 1994 (Gee & Page) as mid-Silurian. The data all confirm that this Ny Friesland orogeny was a major Silurian (Caledonian) event.

SILURIAN HISTORY The highly tectonized western Ny Friesland structure exhibits westward verging, recumbent folding that was sheared sinistrally with N S lineation and extension along the fold axes. Deformation phases may be recognized with isoclinal shear folds and boudinage marking N-S extension superimposed on E-W nappe extension in a continuous transition from compression through transpression. In earlier terminology b-lineation follows a-lineation. WittNilsson et al. (1997) estimated a 200% E W shortening. This would be a minimum value. There was little or no migmatization, even in the rocks which were stratigraphically 18 km down. Folding thickened the sial in spite of syntectonic erosion. The Veteranen Line marks the eastern boundary of a shear zone that approximates to the boundary between the Kortfjellet and Vildadalen formations at the top of the succession in west Ny Friesland. This was probably active during Silurian time within the steeply dipping Planetfjella Group strata to move the Ny Friesland Western Terrane at say 50 to 100 km north with respect to the adjacent Eastern Terrane. The Billefjorden Fault Zone separates the Lower Hecla Hoek rocks from the Devonian strata to the west. As a fundamental fault with a long history, its Silurian sinistral transpression extended through the Ny Friesland Western Terrane but was concentrated near the fault zone as seen by mylonite zones as well as extreme elongation in the neighbouring rocks. The 2-3 km Cambridgebreen Shear Zone, east of the fault of chloritic rocks with some brittle fracture was sheared under greatly reduced load and this was probably mainly during Devonian time. (vi) South Eastern Svalbard Terrane (SEST). Older rocks, as found in North Eastern Svalbard, must underlie the platform cover in southeastern Svalbard and can only be known directly by deep drilling. Two wells in Edgeoya do not penetrate the basement. (b) The Central Province of Svalbard originated in a province comprising basins extending from N o r t h East G r e e n l a n d . The terranes are m o s t obviously distinguished from b o t h eastern terranes by the presence of D e v o n i a n a n d possibly latest Silurian strata. They also include fossiliferous Early C a m b r i a n a n d Early Ordovician c a r b o n a t e strata with different faunas f r o m those of the Eastern Province. T o g e t h e r with the Late Proterozoic rocks they were subjected to Silurian t e c t o n o - t h e r m a l o r o g e n y as part of the East G r e e n l a n d Caledonides. (i) The Andr& Land-Dickson Land Terrane (ADLT) is bounded to the east by the Billefjorden Fault Zone and in the west by the Breibogen Fault Zone. It is entirely covered by the Early to Mid-Devonian Andr& Land Group so that no Silurian events can be detected at the surface. (ii) The Biskayerfonna-Holtedahlfonna Terrane (BHFT) comprises the Precambrian Horst and the Old Red Sandstone Graben and is bounded on the east by the Breibogen Fault Zone and on the west by the Raudfjorden Fault Zone. These N-S faults and the intervening Hannabreen Fault appear to have been sinistrally active from late Silurian through early Devonian time generating conglomerates from their moving fault scarps. How much of the Siktefjellet Group's history is Silurian is not known. But it is likely that these major fault zones became established before Devonian time. This sedimentary story, a response to tectonics, is treated in the next chapter. Within the BHFT is a belt of pre-Devonian and Silurian metamorphosed Proterozoic rocks, i.e. the Krossfjorden Group. (iii) The Western Northwest Terrane of Spitsbergen (WNWT) comprises metamorphosed Precambrian strata bounded on the east by the Raudfjorden Fault Zone and on the southwest by the Kongsfjorden (Hansbreen) Fault Zone and to the southeast by a cover of younger strata. This may be regarded as a simple orthotectonic (Silurian) Caledonian structure. It is constrained in age by Early Devonian sediments resting unconformably on top of a sequence comprising three Precambrian formations in the Krossfjorden Group all folded, the lower strata being altered to layered gneiss. These rocks were then subject to migmatic invasion and melting (the Smeerenburgian Event) which in part resulted in grey foliated granite. A last event was the diapiric emplacement of the Hornemantoppen Batholith, cooling ages of which are latest Silurian to Devonian. Many early determinations of the metamorphic and igneous ages have been recorded with a spread from Late Ordovician through early Devonian with a concentration of Silurian ages. (iv) The Middle Hornsund Terrane (MHDT) in Wedel Jarlsberg Land and Sorkapp Land is bounded to the west by the (Kongsfjorden) Hansbreen Fault Zone and to the north and east by cover of later strata. The age of deformation is certainly post-Canadian and pre-Mississippian and so would be consistent with a Silurian orogeny.

285

To the east of Hornsund High is the southward continuation of the Fold and Thrust Belt of the Paleogene West Spitsbergen Orogen which, with similar vergence, deforms Early Devonian through Early Paleogene strata. There is some question (e.g. Dallmann et al. 1993 in C13G) as to whether the Arkfjellet strata are Early or Late Ordovician. If the latter then a Silurian tectonic episode is necessary. If not then the main Silurian tectonism is just not so well constrained. The Devonian strata define the later limit of the Silurian age of deformation in the zone between the two subterranes described above.

(c) The Western Province of Svalbard originated outside the Caledonides, being n o r t h o f N o r t h G r e e n l a n d and having affinities with both the N o r t h G r e e n l a n d F o l d Belt a n d P e a r y a o f n o r t h e r n Ellesmere Island. Because of similarities with Peary L a n d in N o r t h G r e e n l a n d and especially with Trettin's P e a r y a in Ellesmere Island it is n a m e d the North Greenland Pearya Province. The allochthonous terranes (Svalbard western terranes a n d Pearya) m a y have d o c k e d before or in early Silurian time having been involved in the earlier M ' C l i n t o c k O r o g e n y and then a b o u t to be subjected to D e v o n i a n Ellesmerian diastrophism. Indeed, this collection of terranes m a y have been within the same general province at least t h r o u g h o u t Paleozoic time. The Silurian story (of w h i c h little is r e c o r d e d f r o m Svalbard) is one of sedimentation within a tectonically unstable e n v i r o n m e n t . S o u t h of the N o r t h G r e e n l a n d F o l d Belt is a large terrane of Silurian strata deposited on the G r e e n l a n d c r a t o n a n d deriving m a i n l y from the e r o d i n g C a l e d o n i a n O r o g e n to the east. These western terranes, with a smaller o u t c r o p area than the central or eastern terranes, b o r d e r the west coast o f Spitsbergen f r o m K o n g s f j o r d e n to H o r n s u n d and include Prins Karls F o r l a n d . T h e y are b o u n d e d on the east by the postulated K o n g s f j o r d e n H a n s b r e e n F a u l t Z o n e that w o u l d be mostly obscured by postD e v o n i a n strata, ice or water. The later strata have been folded and thrust eastwards over m u c h of the trace o f the p o s t u l a t e d fault. The constituent terranes o f this Western Province are not so clearly distinguished except geographically. The p r e - C a r b o n i f e r o u s o u t c r o p s are largely V e n d i a n with p r e - V e n d i a n p r o t o - b a s e m e n t . H o w e v e r two areas o f p o s t - D e v o n i a n strata include fossiliferous Late Ordovician to Silurian sediments and other p r o b a b l y Silurian sediments. A l t h o u g h sedimentation reflects an unstable environm e n t its preservation indicates a lack of local orogenic activity, p r o b a b l y t h r o u g h o u t Silurian time in contrast to the intense tectonism of the Central a n d Eastern provinces and a n a l o g o u s to that o f the N o r t h G r e e n l a n d Silurian sedimentary response (Hurst e t al. 1983). Such tectonism, as m a y be distinguished from the Paleogene West Spitsbergen Orogeny, could be m i d - O r d o v i c i a n a n d / o r D e v o n i a n . Ordovician strata are k n o w n in both western Svalbard a n d N o r t h G r e e n l a n d , D e v o n i a n strata in neither. (i) Prins Karls Forland. Separated from Spitsbergen by the Forlandsundet Graben, the sequence passes from Late Varanger tillites through fossiliferous Late Vendian strata which pass up into the turbidite and quartzite Barents Formation (in the Grampian Group) with the Sutorfjella contemporaneous slumped conglomerate that could be Silurian by lithological correlation with the Holmsletfjella Formation in Oscar II Land. (ii) Oscar II Land between Kongsfjorden and Isfjorden. This terrane contains the only Silurian fossils yet recorded in Svalbard. Slumped shelf coral limestones overlie Ordovician strata and are followed by turbidites indicating a mobile Silurian depositional environment. This succeeds an early to mid-Ordovician tectonic phase evident in both Prins Karls Forland and Oscar II Land. Away from this constraining evidence, where two phases of Pre-Carboniferous deformation may be determined, it is difficult to distinguish Ordovician from any Late Silurian or Devonian diastrophism and often even from the ubiquitous Paleogene deformation. (iii) Nordenskiiildkysten between Isfjorden and Bellsund. There is local conformity in which Carboniferous rocks cover Vendian strata. It would seem that the metamorphism and more intense deformation would be Early Paleozoic and the evident faults and thrusts and outcrop patterns would be later. Silurian structure remains to be established. (iv) Northwestern Wedel Jarlsberg Land Terrane between Bellsund and Torellbreen, and west of the Recherchefjorden and Recherchebreen presumed

286

CHAPTER 15

fault, the entire succession is Vendian and pre-Vendian. The next youngest strata within the terrane are Late Eocene to Oligocene so that the evident post-Vendian deformation structure could be Paleozoic and/or early Paleogene except east of Recherchefjorden where they are seen to be preCarboniferous. The structures both east and west of Recherchefjorden were described by Craddock et al. (1985). Two pre-Carboniferous folding phases were determined. (i) Small isoclinal folds, sub-horizontal with axial planar foliation, ridge-groove lineation in foliation, and large recumbent folds were interpreted as strong NNW-SSE shortening with NNW transport. (ii) Later tight to isoclinal folds, axial planar foliation and younger folds, foliation, kink bands and crenulations were interpreted as NE-SE shortening and NE vergence. Although it is clear that these deformation effects are more severe than the later Paleogene structures a variety of attitudes were reported, but their localities were not always mentioned. It is only possible to be sure of a pre-Carboniferous age east of Recherchefjorden (in the Central Province) so that the strong phase (ii) NE vergence would belong to the Central Terranes and match the easterly vergence in middle Hornsund, probably Silurian. The phase (i) with strong NNW vergence of Craddock et al. could be Ordovician, especially if the data derived from west of Recherchefjorden. E.C. Hauser's unpublished K-Ar age determinations were quoted by Ohta (1992) whose map indicated a position of samples probably from the (Early Varanger) Chamberlindalen Formation or near to it. Values from biotite were 337, 347 and 358 Ma and from whole-rock 407 and 358 Ma and from whole-rock 407, 462, 472 and 48 l Ma. The younger values indicate a Carboniferous age and the older ones span Silurian and most of Ordovician time. This would appear to rule out the Paleogene Orogeny as the main tectonothermal event. The title of an abstract by Hauser (1991) reads 'Early Paleozoic deformation of a late Precambrian sequence in West Spitsbergen: a possible link between Svalbard, North Greenland and the Pearya orogen'. This may suggest that the mid-Ordovician ages were regarded as the most reliable (462 481Ma). (v) Southwestern Wedel Jarlsberg Land and Western Sorkapp Land south of Torellbreen. In western S~rkapp Land, west of the projection of the Hansbreen Fault Carboniferous and Triassic rocks constitute the main outcrop covering highly metamorphosed Proterozoic strata of uncertain affinity. This terrane escaped major Paleogene deformation except for some bedding thrusts in the younger strata. The Wedel Jarlsberg Land outcrops to the north of Hornsund and west of Hansbreen while their succession and age are much disputed, but nevertheless agreed by all to be Precambrian. The evident deformation of the rocks may be a product of Paleozoic and/or Cenozoic tectonism. However, combining the reports by Craddock et al. (1985) and Hauser's data in Ohta (1992), the preference would be for Ordovician rather than Silurian tectonism. It is concluded here that there is no evidence in the Western Terranes for Silurian tectonism, the lack of which would fit their position west of the Caledonian front.

(d) The Bjarnaya Terrane. Only one outcrop area of pre-Silurian strata is available. Bjornoya with its neighbouring submarine rocks is a distinct terrane separated from the main archipelago. Its nearest affinity may be with eastern North Greenland and possibly north of the Central Svalbard Province. The affinity of conodonts from the Antarcticfjellet Formation of Bjornoya with those in the coeval Caradocian (Black River) formation of kronprins Christian Land of easternmost north Greenland suggest an attachment of the two areas (Armstrong & Smith in press). Moreover, the Caradoc age of the strata noted by Holtedahl and confirmed by Smith is later than that of the Canadian strata of the Central and Eastern Province of Spitsbergen. Bjornoya might therefore have occupied a position north of the Central Province and towards the northern end of the East Greenland Caledonides. Late Proterozoic and Early to Mid-Ordovician carbonate strata show no evidence of contemporary tectonism which contrasts with the western Svalbard terranes. The structures show westward thrusting of the competent beds and more intense folding and

thrusting of the incompetent (Vendian) slates. The structures are covered unconformably by latest Devonian continental clastics. Thus the deformation can be constrained only as post-early Caradoc (Late Ordovician) and pre-latest Devonian and so is consistent with the main Caledonian events of the Eastern and Central terranes and with a presumption that the main tectogenesis was Silurian; but Late Ordovician and Late Devonian (Svalbardian) components cannot be ruled out.

15.5.2

Silurian fault and shear motions

Having considered the characteristics of the many Svalbard terranes outlined above, and their postulated original locations in the Greenland and Canadian provinces, it remains to be considered how the three Spitsbergen Provinces travelled to dock in latest Devonian time to form the single composite terrane of Svalbard that has remained largely intact from its Carboniferous to Cretaceous location north of Greenland and its Cenozoic translation to the present configuration. For the present purpose the Silurian displacements need to be identified. Starting from their Early Ordovician position in the three Greenland provinces it has been argued that the Iapetus Ocean was closing during Ordovician time, not least from the evidence of converging faunas (McKerrow & Cocks 1976) which suggests that the main sinistral strike-slip motion necessary to achieve the composite terrane had not then begun. The main Silurian Caledonian Orogeny appears to have begun with the final closure of Iapetus. The collisional tectonic phase causing folding, nappe formation, thrusting along the eastern margin of Greenland was recorded in the structures of the Eastern and Central terranes of Svalbard and the thrust structures of Baltica. The motions between Laurentia and Barentsia plus Baltica, having exhausted a compressive phase, began to move sinistrally with oblique compression (i.e. transpression). The Eastern Svalbard Province had the greatest distance to travel (say 1000 to 1200km) and the transpressive structures are most evident in western Ny Friesland. Perhaps 50 to a maximum of 100 km sinistral displacement was effected within the two or three km of strata just west of the Veteranen Line. Possibly a further 200km was distributed within the main body of the rock, and possibly another 100 or 200km was effected in shear and mylonite zones east of the Billefjorden Fault (see Fig. 16.10). Already in Late Silurian time the main transpressive motions were transforming to simple strike-slip transcurrent displacement which uses less energy. Thus the second part of the 1000-1200 km travel was more likely by transcurrent faulting. East of the main Billefjorden Fault is the N-S Cambridgebreen Shear Zone, 2-3 km wide, of chlorite schists retrograded from amphibolite. This is evidence of a substantial shear under a much reduced tectonic overburden. Arguments from Devonian sedimentation suggest that not less than 200km of sinistral motion was likely along the Billefjorden Fault Zone and probably more. So that, for example, if 300 km strike-slip were displaced along this fault zone, most of it in Late Devonian time, some might have begun in Silurian and continued through Mid-Devonian time. On the other hand the Central Province had a much shorter distance to travel before docking north of Greenland. There is evidence of strike-slip within the central terranes in the north (as in the Breibogen and Raudfjorden faults) and at the western margin as at Hansbreen. Therefore a component of say 1000-1200kin transport for the Eastern Province may have been taken up within and beside the Central Province. Moreover, there is evidence of some sinistral transpression and strike-slip in the Western Province at the margins of the Forlandsundet Graben. This argument is resumed and completed at the end of the Devonian story (Chapter 16) with a conceivable plot of the net contribution of each transpression and fault zone at different times to achieve a final docking from the initial positions within the

SILURIAN HISTORY

TKF, was said to have come from near west Spitsbergen in spite of major stratigraphic differences, when west Spitsbergen affinities relate to Pearya. On the other hand the East Spitsbergen Terranes, with marked similarities to Central East Greenland, were apparently always north of the TKF system.

~,Melville>"~'~ Pearya /

~,~(and Bat~h~uFst~R)' gnes~

~-~, x ~

Western

Svalbard Terranes

15.5.3 ENGP

~/~; ~j I

e,~\

Central Svalbard

II Terranes

EG

_42,,

o o GP

I

Eastern

,,-

L4

Svalbard Terranes

T I A,e25 "-~/

/

i//I// //////

i / // / I ~//// // .

287

/~ Fold vergence

/

Fig. 15.7. Schematic illustration of terranes surrounding Greenland at approximately the beginning of Silurian time, with the closure of the Iapetus Ocean. The four provinces relating to Svalbard terraces are indicated by the dashed circles: EGP, East Greenland Province; NEGP, Northeast Greenland Province; ENGP, Eastern North Greenland Province; and NGPP, North Greenland Pearya Province with Western Svalbard Terranes. Small arrows indicate approximate directions of Silurian tectonic vergence. The Caledonian front is defined in a broad sense. Parts of Norway and Scotland are included only to show schematically their approximate relative positions. A more precise palinspastic map would require further research than was available for this project.

Greenland provinces. The equation is necessarily speculative and with very many options; but each should somehow add up to a total of say 1000-1500 km. A qualitative diagram to indicate the relative positions of the terranes through Silurian time is shown in Fig. 15.7. In conclusion, it would greatly weaken the case for major sinistral strike-slip components in Svalbard if such displacements were not recognized in the projected zones to the south. Indeed Svalbard may have led somewhat in this respect. However, quite independent evidence has appeared for such sinistral motions in Greenland, Scotland and Newfoundland at least. One of many is the paper 'Sinistral transpression and the Silurian closure of Iapetus' (Soper et al. 1992). Holdsworth & Strachan (1991) concluded similarly for Northeast Greenland. The Trollfjord-Komagelv Fault in Finnmark (Johnson, Levell & Siedlecki 1978) was said to have dextral motion on palaeomagnetic evidence Max & Ohta (1988), by inspection of mapped fault lines in northern Norway and offshore western Spitsbergen in particular, argued that Cenozoic faulting was controlled by basement faults, some possibly going back to Precambrian time. The thrust of their thesis is that the TrollfjordenKomagelv Fault (TKF) in Finnmark and some faults in southwest Spitsbergen were segments of the same system which parallels some Cenozoic faults. However, they noted that the early movement was sinistral in Spitsbergen and dextral in Norway. Little or no evidence was provided or cited as to the age of the critical early movements, and evidence as to stratigraphic affinity was ignored so that the Barents Sea Group, north of the

Baltica, Barentsia and lapetus

A major consequence of the strike-slip hypothesis developed in this work is that Baltica moved north at least as much as the East Svalbard Province with respect to Greenland. Indeed northern Norway on this hypothesis could have been opposite southern East Greenland when Iapetus closed between them, whereas the East Svalbard Province was already adjacent to central or northern East Greenland and on the same side of Iapetus. Therefore the collisional histories of the two segments of the orogen would be different. A similar situation may apply as between the Central Svalbard Province and Northeast Greenland. The southern segment of the Caledonian orogen would result from collision between opposing lithosphere plates with the development of the great thrust sheets in the Scandinavian Caledonides. Barker & Gayer (1985) offered a Scandinavian perspective of the same event. The northern segment, involving eastern and central Svalbard terranes exhibits less extensive nappe transport. The folding, with minor thrusting resulted from the compression of Barentsia against Greenland. Barentsia is a postulated extension of Laurentia situated to the east of Ny Friesland and exposed in eastern Nordaustlandet. Russian geologists have long regarded this as a continental foreland. Harland & Gayer (1972) introducing the name Iapetus and delineating its approximate suture, suggested that the Hecla H o e k geosyncline developed between Greenland and the Barents Craton in a Proto-Iapetus trough or basin. This might be regarded as an offshoot of Iapetus, i.e an aulacogen which never became an ocean. It preceded the opening of Iapetus by about 400 My and developed on a gently subsiding (?thin) continental basement on a cooling mantle (Harland 1969) (Fig. 15.8).

Late

A

(a)

Ordovician - Early Silurian (c. 440 Ma) Glaciogenic deposits

(b)

Mid-Silurian (c. 425 Ma)

SOUTHCHINA

~LAURENT\I

~

GONDWANA /

Fig. 15.8. (a) Late Ordovician to Early Silurian global palinspastic reconstruction, with glacigenic deposits indicated by black triangles. (b) (A Mid-Silurian palinspastic reconstruction (adapted from Torsvik et al. 1996 with permission of Elsevier Science, Amsterdam.).

288

CHAPTER 15

Gee (1989) and Gee, Johansson et al. (1995) have emphasized the abundance of zircon ages in Svalbard approximating 950 Ma as Grenvillian and that the Grenvillian Orogen might have caused the opening of the Iapetus Ocean, in spite of a delay of 400 million years. On the other hand the Proto-Iapetus trough might well have been a more immediate response. This idea might be supported by the beginning of the post-Harkerbreen, post-Brennevinsfjorden successions with magmatism and volcanism around 950-900 Ma in the Planetfjella Group. This is speculative, but not unlikely because further south along the margin of Greenland there are the Moinian, Dalradian and Torridonian sequences of Laurentian Scotland. Indeed, a major part of the Caledonian Orogen is Precambrian, i.e. mostly pre-Iapetus.

15.6

Sequence of Silurian (main Caledonian) events

The very limited control of Silurian history from Svalbard stratigraphy corresponds to the Caledonian orogenic events that are recorded in the older rocks throughout the Central, Eastern, and Bjornoya Provinces. The only sure Silurian strata belong to the Western Svalbard Province which north of Greenland was well to the west of the Caledonian front. This North Greenland Pearya Province had already undergone Early to Mid-Ordovician tectogenesis. North Greenland, however, preserves the debris transported westwards from the Caledonian Orogen and the sediments are latest Ordovician and Early Silurian turbidites. The eroding nappes advanced over the Ordovician carbonates. These events appear to predate the main Caledonian thrusting of Scandinavia and the East Greenland Caledonides (Hurst et al. 1983). Away from this region, west of the Caledonides and including the Western Svalbard Province there is a biostratigraphic hiatus from about Llanvirn through probably latest Silurian time. That is a maximum of 15-20 million years of Late Ordovician time and about 25-30 million years of Silurian time, probably about 40 million years. The closing of the Iapetus Ocean, generally taken as an Ordovician process partly because of convergence of faunas was not so clearly documented as shown by Zalasiewics, Rushton & Owen (1995) who argued that environmental changes, not least from the late Ordovician ice age, may have influenced the faunas more than the increasing proximity of Laurasia and Baltica. The following model, while poorly constrained, is at least consistent with the above and other known data. (1) During Ordovician time the Iapetus Ocean was closing. (2) Uplift from collision of Barentsia and Baltica and Laurentia (with most of the Svalbard terranes) may have begun in later Ordovician time and possibly earliest in North Greenland. This is consistent with the lack of Late Ordovician deposits in the Eastern or Central Provinces of Spitsbergen and in East Greenland.

(3) The main Silurian collision generated westward-vergent recumbent folds, nappes and thrust sheets in East Greenland and in eastern Svalbard. Some boudinage developed in the extending recumbent limbs (a lineation). From Scandinavian evidence Baltica may have underthrust Laurentia (Gayer 1989) with evident eastern vergence in Norway. (4) In the Central Svalbard Province the compressive vergence was probably eastward. In inner Hornsund the thrusting verges E and south of Bellsund NE as also in northwest Spitsbergen. (5) The convergent regime between Baltica and Laurentia (with Barentsia) transformed slowly into the oblique compression which is so well exemplified in the (type) transpressive structures of western Ny Friesland. The result was a sinistral shearing of the early compressive structures leading to N-S elongation. This interpretation replaced (Harland 1971) the more symmetrical indentor model of Harland & Bayly (1958) and Harland (1959). Boudinage, mineral lineation and N-S extension of psephite stones mark this stage (b-lineation). The rocks now exposing these structures were at a depth of about 20 km deforming a pile with a stratal overburden of about 12 km. The metamorphic climax was mid-Silurian. (6) Oblique motion changed from transpression with a dominant compressive component to one with a dominant strike-slip component so developing the marked shear and mylonite zones in western Ny Friesland. The sinistral shear was not so marked in Nordaustlandet to the east nor indeed in eastern Ny Friesland. Thus, in the Eastern Province transpressive deformation was concentrated in western Ny Friesland. East of the Veteranen Line there was compression with little noticeable shear, so forming relatively open upright folds. In northwest Svalbard, in the terrane that travelled a much shorter distance than the Eastern Province, sinistral shear is nevertheless evident both in deformation structures and in the en 6chelon granite lenses within metasediments of the Kongsfjorden Group. However, the last resulting shear at increasing depth may have generated localised granitic magmas. In any case the shear stresses transmitted across the Veteranen Line may have opened the way for diapiric intrusion of the Ny Friesland batholiths. No analogy need be sought for the batholiths of Nordaustlandet which appear to have originated in Proterozoic time. On the other hand the Hornemantoppen Batholith in the northwest formed in a demonstrable, yet modest, sinistral regime allowing for local pull-apart intrusion. (7) In the final Silurian episode strike-slip (transcurrent) displacement was probably focused in relatively distinct fault zones (see Fig. 15.4). (8) Transcurrence continued into Devonian time with rapid erosion of the orogen and resulting in shear structures with brittle fracture. The batholiths, emplaced at about the Silurian-Devonian boundary, continued to cool in Devonian time. In Gondwanaland global perspective, the Cambro-Ordovician assembly of Unrug (1996) set the starting point for the SilurianDevonian translation of Svalbard's fragments to their Pangea resting place.

Chapter 16 Devonian history W. B R I A N 16.1 16.1.1 16.1.2 16.1.3 16.2 16.3 16.3.1 16.3.2 16.3.3 16.3.4 16.4 16.4.1 16.4.2 16.4.3 16.4.4 16.5 16.5.1 16.5.2 16.5.3 16.5.4 16.5.5

HARLAND 16.5.6 16.5.7 16.5.8 16.6

Devonian time scale and correlation, 289 International time scale, 289 Biostratigraphic correlation, 289 Devonian Isotopic ages (c. 410-360Ma), 291 Devonian succession, 291 Devonian biotas, 291 Fossil fish, 291 The record of fossil fish in Svalbard, 292 Devonian invertebrates of Svalbard, 293 Devonian plants of Svalbard, 294 ?Silurian and Devonian sedimentation, 296 Siktefjellet and Red Bay groups sedimentation (Friend et al. 1997), 296 Wood Bay Formation sedimentation (Pragian and Emsian) Late Early Devonian, 298 Mid-Devonian sedimentation, 299 Late Devonian-Famennian sedimentation, 299 Devonian tectonics, 299 Albert I Land High, 299 Mitrahalvoya, 300 Blomstrandhalvoya-Lov6noyane Basin, 300 Raudfjorden Fault (RFF), 300 Biskayerfonna-Holtedahlfonna Terrane, 300

16.6.t 16.6.2 16.6.3 16.6.4 16.6.5 16.6.6 16.6.7 16.7 16.7.1 16.7.2 16.7.3 16.7.4 16.7.5 16.7.6 16.7.7 16.7.8 16.7.9 16.8

Svalbard is part of the Old Red Sandstone province with affinities in East Greenland, Norway, Appalachian N o r t h America and, of course, the British Isles where the Devonian Period was defined. This allows Devonian history in this region, controlled by Caledonian events, to form a neat and natural chapter, though not necessarily a global one. Old Red Sandstone environments in each area were already becoming established in Late Silurian time. Olaf Holtedahl was the prime author of both Caledonian tectogenesis in Svalbard and the Old Red Sandstone aftermath. Of the many and varied biotas of Svalbard the fossil fish have made remarkable and classic contributions to Spitsbergen geology. The earliest 'Old Red Sandstone' Spitsbergen strata have yet to yield evidence of age and so may be latest Silurian (Siktefjellet Group). But the earliest Devonian strata to be identified biostratigraphically begin with the Red Bay Group. Similarly the (major) Ny Friesland Orogeny and the various late orogenic granite emplacements, while initially Silurian, continued at least to cool in Devonian time. For convenience the orogenic events that may

continue as early Devonian are treated in the Silurian chapter and the sedimentary events that may be Silurian are treated here. Devonian successions in Svalbard are known only from terranes which are postulated to have originated from the North East Greenland Province. No record has yet been established for Devonian strata in Svalbard either from the eastern terranes (East Greenland Province) or from the western terranes (North Greenland-Pearya Province). Moreover, the East Greenland succession lacks Svalbard's Early Devonian record. The main Devonian outcrop is confined to what has commonly been referred to as a graben or half graben because of its sharp eastern boundary against the N y Friesland Orogen (Fig. 16.1). It is argued later that the sedimentary basin extended further to the east and that the Ny Friesland orogen only became juxtaposed in Late Devonian time by strike-slip rather than being in the present relationship but beneath the basin.

16.1

Table 16.1. Divisions of the Devonian with ages (Ma) from (1) Harland et al. 1990) and (2) Tucker & McKerrow (1995) Epoch

Stage

(1)

(2)

Tournaisian 363 Famennian Late Devonian

367 Frasnian 377 Givetian

Mid Devonian

381 Eifelian 386

391

390

400

396

412

4O9

417

Emsian Early Devonian

Pragian (Siegenian) Lochkovian (Gedinnian)

Breibogen Fault (BBF), 301 Andr6e Land-Dickson Land Terrane, 301 Billefjorden Fault Zone (BFZ), 301 The question of sinistral Paleozoie strike-slip faulting, transpression and transtension, 303 A controversial hypothesis, 303 Billefjorden Fault Zone (BFZ), 303 Postulated Kongsfjorden-Hansbreen Fault Zone (KHFZ), 305 Fault zones in northwest Spitsbergen, 305 Other Fault zones within Svalbard, 305 Ellesmere Island and North Greenland, 306 Some of geotectonic conclusions, 306 Sequence of events through Devonian time, 306 Latest Silurian-Early Devonian events (i.e. pre-Lochkovian), 306 Haakonian faulting and sedimentation, 307 Lochkovian (Red Bay Group) sedimentation, 308 Postulated Late Lochkovian to Early Pragian movements, 308 Pragian to Emsian, i.e. mid- to late Early Devonian, 308 Eifelian-Givetian (mid-Devonian), 308 Mimer Valley Phase (early Svalbardian), 309 Frasnian-Famennian (Late Devonian) events, 309 Late Famennian events, 309 A Lomonosov conjecture, 309

16.1.1

Devonian time scale and correlation International time scale

The international divisions shown in Table 16.1 are used with approximate ages (Harland et al. 1990) and as updated by Tucker & McKerrow (1995). The divisions are based on marine faunas: ammonoids and graptolites and (recently and more precisely) conodonts for correlation purposes both within Svalbard and in international correlation, especially within the standard Anglo-Welsh Borderland sequence. These index fossils are unsuited to non-marine facies of Old Red Sandstone type and so a major Devonian biostratigraphic preoccupation has been to correlate the standard marine zonation with the vertebrate (fish) faunas. In this the Spitsbergen contribution has been outstanding. At the same time advances in palynology have provided a new lever especially in later Devonian floras.

16.1.2

Biostratigraphic correlation

Early Devonian correlation. Perhaps the most authoritative account of Early Devonian biostratigraphy in Svalbard was by

290

CHAPTER 16 /12 ~

/9 ~

~81 ~

/18 ~

/15 ~

121 ~

/24 ~

SVALBARD DEVONIAN OUTCROPS

~

\ 27 ~

<3

5

O

8o'

7_9 ~

79 ~

|

1 Andree Land 2 Chydeniusbreen Batholith 3 Dickson Land 4 Hornemantoppen Batholith 5 Liefdefjorden (Liefde Bay) 6 Marietoppen 7 Mimerdalen (Mimer Valley) 8 NordenskiSIdbreen Batholith 9 Raudt]orden (Red Bay) 10 Reinsdyrflya 11 R~edvika 12 Sikte~ellet 13 Woodt]orden (Wood Bay) ) 14 Gr~huken (Grey Hoek) ! florden (Wijde BaY)7g1

Ii

!

I

e

--.s

e

, ;',,~ L:") -' "-~ J ~ ~ -o

t

i

Z8 ~

__~

- ~ i

Post-Devonian

77~~

i

~

Devonian strata Siluro- Devonian strata

.-~..

~

.

'12 ~

z6 o

,0

,

~ , /15 ~

,

1,0o /

121 ~

?Devonian thermal event

~

Siluro-Devonian batholiths

~

Pre-Devonian

i

/24 ~

Fig. 16.1. Outcropmap showingthe distributionof Devoniandepositsin Svalbardand withnumberedplacenamesincludinglocationsof identifiedmagmatism. The large plus signsin Nordaustlandet refer to isotopic ages interpreted here in section 16.8 'A Lomonosovconjecture'. Dashed lines limit ice cover.

DEVONIAN HISTORY Blieck, Goujet & Janvier (1987), modified by Gjelsvik & Ilyes (1991) and by Ilyes, Ohta & Guddingsmo (1995). The oldest vertebrate fauna first reported was from the Psammosteus horizon on Fr~enkelryggen, described first by Kiaer & Heintz (1935), and of Lochkovian age by correlation with the British sequence. Blieck et al. noted correlation with Turinia pagei from the pococki zone in Britain, which is found in the Monograptus uniformis assemblage of Podolia and is characteristic of the initial Devonian fauna, as defined in the stratotype section for the Silurian-Devonian boundary at Klonk in Bohemia. Gjelsvik & Ilyes showed that the Psammosteus horizon probably belonged to the upper Andr6ebreen Formation. And then a discovery in an island in Liefdefjorden showed that a similar fauna with the cyathaspid Anglaspis g]elsviki and the pteraspid Protopteraspis micra could also be correlated with the pococki zone in Britain. The Silurian-Devonian boundary in Spitsbergen may be somewhat earlier, above or within the Siktefjellet Group. The Red BayWood Bay boundary may be Late Lochkovian or early Pragian according to Goujet (1984) and, by correlation of his newly established Sigurdfjellet Division (at the base of the Wood Bay Formation) with British faunas, he concluded that the boundary would probably lie within that division. Consequently the whole of the Red Bay Group would approximate to the Lochkovian stage and almost the whole of the Wood Bay Formation would be Pragian and Emsian (see below). The early-Mid-Devonian boundary (Emsian-Eifelian) occurs somewhere near the top of the Wood Bay Formation. Orvig (1969) thought it to be somewhere in the Stordalen division or as high as the Verdalen Member.

Mid-Devonian correlation. Blieck, Goujet & Janvier (1987) following earlier work regarded the Grey Hock, Wijde Bay and Mimerdalen formations as Eifelian (Ilyes 1995). From the Grey Hock Formation fish, bivalves, gastropods, ostracods and plants, earlier workers (Foyn & Heintz 1943; Friend 1961; Arvig 1969; Murashov & Mokin 1979) suggested a late Emsian to Eifelian age. The Wijde Bay Formation was thought to be late Mid-Devonian: late Eifelian to Givetian, (Nilsson 1941; Foyn & Heintz 1943; Murashov & Mokin 1979) on the basis of fish, bivalves and plants. The Mimer Valley Formation was dated from top to bottom by Allen (1967) using miospores. At the base his Emsian-Eifelian Eximus assemblage occurs, followed by the Givetian Triangulatus assemblage to the top of the Planteklofta Member. He failed to locate definite evidence of Late Devonian age, but Vigran (1964) also using miospores, suggested a Frasnian age for the higher members. Murashov & Mokin (1979) from flora considered the age to range from Late Eifelian-Givetian (Estheriahaugen Member) through Late Devonian (with Frasnian fish and spores in the Fiskeklofta Member possibly to Early Carboniferous on the basis of lycopods in the uppermost Planteklofta Member. According to Westoll (1951) and Halstead-Tarlo (1973) the psammosteid vertebrate fauna of the Fiskeklofta Member suggested a Late Givetian age. Hoeg (1942) considered the microflora to be Middle to Late Devonian. The Marietoppen Formation, which correlates lithologically with the extensive Wood Bay Formation and up to the Grey Hock Formation has yielded little critical age data (Birkenmajer 1964). Its middle division may approximate the Early-Mid-Devonian boundary and the upper division may extend to correlate with the Wijde Bay Formation (Murashov 1976).

Late Devonian correlation. The Roedvika Formation of Bjornoya yielded material of the classic A rchaeopteris flora. Miospores according to Kaiser (1970, 1971, 1974) made the Vesalstranda Member and the lower Kapp Levin Member Famennian and the upper Kapp Levin and Tunheim members Tournaisian. The floral break, observed by Schweitzer (1969) between the Vesalstranda and Tunheim members, agrees in making the Devonian-Carboniferous boundary fall somewhere in the Kapp Levin Member (Fig. 16.2). Recent work in Spitsbergen suggests that the lower member of the H6rbyebreen Formation, generally considered to be Tournaisian may be Famennian (van Veen pers. comm.).

291

The Devonian succession thus ranges from earliest Lochkovian to latest Famennian with a major break in the (?Givetian) Frasnian and early Famennian, the time of the Svalbardian deformation.

16.1.3

Devonian isotopic ages (c. 410-360 Ma)

From the data in Chapter 3 (Fig. 3.9) the following generalizations are suggested. (a) The main body of values that fall conspicuously within the Devonian time span are those from Nordaustlandet where it appears that the granites, migmatites and metasediments, some if not all of which, originated in Proterozoic time, were nevertheless subject to a Devonian thermal regime sufficient to reset the mineral systems with the exception of zircons. (b) In Ny Friesland the dominant metamorphic ages were Silurian (also rejuvenated from Proterozoic genesis) but the late tectonic granite batholith spans Silurian and Devonian time suggesting late Silurian emplacement and Devonian cooling. (c) The Richarddalen Complex yields a long history of thermal events from Paleoproterozoic with evident Silurian rejuvenation and possibly some Devonian cooling. (d) The main northwestern metamorphic body and granite ages divide so as to suggest major Silurian tectonothermal activity with a significant Devonian aftermath. (e) The remainder of determinations from Svalbard, mainly in western and southwestern Spitsbergen only yielded exceptional Devonian ages which may not be significant. The above enigma of Nordaustlandet history may well be elucidated in the coming years as further exploration of this remote area proceeds (see Section 16.8).

16.2

Devonian succession

To the principal Devonian outcrops in northwest Spitsbergen (Chapter 8) are now added the Marietoppen Formation from south Spitsbergen (Chapter 10) and the Roedvika Formation from Bjornoya (Chapter 11). These are correlate and summarized in Fig. 16.2.

16.3 16.3.1

Devonian biotas Fossil fish

For many years fossil fish were one of the few internationally renowned phenomena of Svalbard geology. Many expeditions collected material from noteworthy fossil horizons. At that time when there was little lithostratigraphical description beyond Holtedahl's (1914) work until that of Friend (1961). Devonian fish are valuable biostratigraphically because their exoskeleton (armoured plates and scales) are resistant to disintegration and even small fragments may be identified from their complex internal structure. The Old Red Sandstone facies are commonly referred to as nonmarine and some marine occurrences may be explained by fluvial connection to the sea. However, there are sufficient instances of mixed or marginal assemblages for the environmental requirements to remain a mystery. There is, in any case, an enormous variety of forms so it would be unwise to generalize. The earliest Ordovician fish were marine so that any lower salinity development would be an adaptation. Perhaps most of the basic evolutionary developments, beginning in Ordovician time, were largely accomplished at least by Late Silurian time. Certainly the Devonian period spans nearly all the phyllogenetic taxa. They survived either from Silurian to become extinct before Carboniferous time or developed in Devonian time and continued, often through to the present day.

292

C H A P T E R 16

3 u

EPOCH

STAGE

NORTHERN SPITSBERGEN Ma

HORNSUND

N.W. and Main Basin Tournaisian

BJORNOYA

Mimerdalen TunbeimMbr.

Hastarian HORBYEBREEN

80 m

FM.

[] -R]Cy

KappLevin Mbr. [ ] ROEDVIKA FORMATION 360 m

Famennian

80 m

[]

Vesalstranda Mbr. 200 m [] I

basement Late Devonian erosion ConglomerateMbr. L. Planteryggen SandstoneMbr. 400 m FiskekloRa Mbr, 9

Frasnian }77.4 ~

~

erosion

~

WIJDE BAY

Givetian

< zO

[ ] MIMER VALLEY 130 m FORMATION 740 m []

FM.

500-600 m Middle Devonian

380.8

Eifelian }86

li

}90.4 (west)

Early Devonian

o-5oo m

}96.3 R E D B A Y GROUP

Lochkovian (Geddinnianl

900 m

600-750 m 9

t08.5 F J E L L E T GROUP

ALBERTBREEN FM.

300-1400 m

LII I JI=RORGFJELLET FM. RABOTPASSET FM.

100-400m 100 m

550 rn

[]

I

Lower Austt]orden Sandstone Member

350 m

basement

A

Epochindicated

9

Epoch confirmed

[]

Stageindicated

9

Stage confirmed

9

Skam. SkamdalenMember 60-100 m

ANDRC:EBREEN FM. (3 mbrs) upto 700 m 9 RIVIERATOPPEN FM. 2 mbrs 3 - 40

SIKTE-

I I

I

FRAENKELRYGGEN FM.

[7 A

Middle

[]

I

BEN NEVIS FM.

.

I

-

i~Div. []//,~ 11000-1500 m 7 X

~

Upper 150 m

9 MARIETOPPEN A ] FORMATION 1050 Ill

~j

m~ ) ~ , e ~ - ~

Pragian (Siegenian)

.

110 m

I.......... I KeltiefJeUet/Lykta[ ~ / I WOOD BAY ~ Div. //co& FORMATION ~ - 9 0 0 m I'-J~ ~ ........ ..,-~..~ _. _ .

WOOD BAY FM Rnnnlm .......

erosion

EstheriahaugenMbr.

I Forkdalen Mbr. /~ GREY HOEK [ 630 m ANDRI~E FM. I Tavleflellet Mbr. A LAND 1000 m I 300 m I GjelsvikfjelletMbr. GROUP ! loom I~erl I 9 I "~' Stjerda}en Div,

Emsian

9 ~

9

NOT EXPOSED

Vet. VerdalenMember 0-100 m

R.C. RifleoddenConglomerate S.C. Skjoldkollen Carbonate Mbr, V.G. VaktarenGreen Mbr. O.G. OrsabreenGreen Mbr.

basement

Fig. 16.2. Stratigraphic correlation chart for the (Devonian) Liefde Bay Supergroup of Svalbard. The latest Famennian and Tournaisian strata belong to the succeeding Billefjorden Group.

O f the two superclasses o f fish, the Agnatha (without jaws) and the Gnathostomata, the former were d o m i n a n t in Early D e v o n i a n time and were superseded entirely by the latter by late D e v o n i a n (with the exception o f the living cyclostomes that lack hard parts). The gnathostomes were more efficient predators with moveable jaws and more efficient gill structures than the agnathans (Fig. 16.3). The more primitive agnathans divide into pteraspidomorphs and cephalaspidomorphs; the gnathostomes comprise the teleosts (bony fish) and elasmobranchs (cartilaginous fish). The classification used here is simplified from Moy-Thomas & Miles (197 l) and their stratigraphic ranges also from Halstead-Tarlo (1969, 1973) and from Andrews, Gardiner, Miles & Patterson (1967). The agnathans lack articulated jaws and pelvic fins; they appear to have had a dominantly benthonic mode of life. The pteraspidomorphs include the earliest known fossil heterostracans and thelodonts which are both mid- or Early Ordovician forms, none of which survived into Carboniferous time. In the former an exoskeletal layer of elongated denticles have fused to form ridges and grooves. The head and front part of the body is enclosed in a shield formed of bony plates, and the body with overlapping scales. The mouth is generally ventral but may be dorsal (in psammosteids). Different arrangements of the plates enable complex taxonomic schemes to be constructed. The thelodonts are not so well known having denticle rather than armour coating. The cephalaspidomorphs are also bony except for the cartilaginous living forms (lampreys and hagfish). They range from Late Silurian to Late Devonian and the main osteostracan infra-class is amongst the best known of Devonian forms, from their detailed cranial anatomy (e.g. Stensi6 1927, 1932). The head has a rigid plate above mouth and gill openings. The body is more flexible, scale-covered and with distinct pectoral fins. Nearly all forms are Silurian or Early Devonian. Cephalaspidomorphs include anaspids and Paleospondylus (Mid-Devonian) of uncertain affinity.

There are two Devonian classes or subclasses whose phyletic relations are uncertain: acanthodians and placoderms. Moy-Thomas & Miles placed the former with the Teleostomi and the latter with the Elasmobranchiomorphi but neither taxon is typical of the teleosts nor elasmobranchs which have well developed internal skeletons (respectively bone and cartilage). The Late Silurian acanthodians are the earliest of the jawed fish known. They continued through Permian time. They are of shark-like appearance with large eyes and small olfactory organs. They were probably successful, being amongst the earliest nektonic forms. Their demise in early Carboniferous time may have been from competition with the rapidly developing actinopterygians, probably from a similar stock. The placoderms are almost exclusively Devonian. They are dorsoventrally compressed. The head shield articulates with the trunk shield of bony plates behind which the body tapers. There are at least six diverse orders including arthrodires and antiarchs. Finally the two principal sub-classes of modern fish, the osteichthes (Actinopterygii, Crossopterygii and Dipnoi) have a typical internal skeleton of bone and are free-swimming, presently with air sacks. In summary the distribution in the fossil record is summarized in Fig. 16.4 (based on Moy-Thomas & Miles 1971, Tarlo 1967 and Andrews et al. 1967).

16.3.2

The record of fossil fish in Svalbard

A n impression (only) o f the fossil record in Svalbard is plotted in Fig. 16.5. Only genera are tabulated and this is not a definitive list because the literature has not been scanned and authorities differ somewhat in their taxonomy. The sources used for it are (a) Friend (1961), who listed all species (of all taxa), then recorded in each lithostratic division their various occurrences. This is referenced to the original descriptions. It should be noted that, for example, the

DEVONIAN HISTORY

293

genus Cephalaspis in the Fra~nkelryggen Formation has not less than 17 species recorded. The recurrence of generic names in the table does not imply identical species. Figure 16.5 has lost this detailed specific and lithostratic information in order to combine it with (b) a more recent assessment of Early Devonian faunas listed chronstratigraphically by genera (Blieck, Goujet & Janvier 1987). In addition the new finds from the Andr6ebreen Formation are added from (c) Gjelsvik & Ilyes (1991); this earliest fauna awaits description. The youngest unit in Bjornoya is taken from (d) Horn & Orvin (1928). A further and still older record was reported by Ilyes, Ohta & Guddingsmo (1995) from the Wullfberget Member. From this plot it is clear that Svalbard alone provides a significant record for the study of fish evolution. This shows that whereas all the principal taxa are represented, the Early Devonian (Lochkovian) faunas were dominated by the two main classes of a agnathans and some later acanthodians, and in Pragian time by abundant placoderms. Modern taxa are present but are not significant constituents of the biota until Late Devonian. Each record may represent an immense amount of laboratory dissection often elucidating the detailed cranial anatomy and only some of that work is referenced here. The principal coherent account, prior to Friend (1961), was by Foyn & Heintz (1943) who reported the results of an international collecting expedition. The palaeontological studies have continued throughout this century. A recent biostratigraphic account of the Wood Bay Formation and the Red Bay Group was by Blieck, Goujet & Janvier (1987). These units span almost exactly the Early Devonian Epoch. Other references include: Kiaer: 1916; 1928, pteraspids and cephalaspids; 1930, Ctenaspis; 1932,

cyathaspids. Stensi6:1918, general and crossopterygians; 1927, cephalaspids.[?] Holtedahh 1920, Holoptychius. Heintz, A: 1928, Homosteus and Heterosteus; 1929, acanthaspids; 1935,

Holonema; 1937, Lunaspis; 1962, Arctolepis. Kiaer & Heintz: 1935, cyathaspids-poraspids.

WiingsjS: 1937, Brenneviaspis; 1952, cephalaspids. Nilsson: 1941, antiarchs. Siive-Siiderbergh: 1941, Downtonian faunas. Jarvik: 1942, crossopterygians and lower gnathostomes. Heintz, N: 1960 Pteraspis; 1962, Gigantaspis; 1965, Doryaspis; 1968; pteraspids; 1972, thelodonts. Orvig: 1969, 1971, arthrodires and thelodonts. Blieek: 1975, Althaspis; 1982, 1983, heterostostracans. TaUmaa: 1978, thelodonts Valyukyariehyas: 1981, acanthodians. Blieek & Goujet: 1983, Zascinaspis. Blieek & Heintz 1979, heterostracans; 1983, cyathaspids. Ilyes: 1995, acanthodians. Ilyes, Ohta & Guddingsmo 1995, heterostracans. Much material now awaits detailed descriptions to parallel some of the early elegant investigations.

16.3.3

Devonian invertebrates of Svalbard

Devonian invertebrates were marine or nearly so, hence their limited record in the typical fluvial Old Red Sandstone facies. Their presence thus indicates a marginal marine environment.

Conspicuous elements of Early Devonian marine faunas are the large arthropods - the eurypterids, an order within the class Merostomata (subphylum Chelicerata). They were marine (gill-bearing) arachnoids, most later arachnoids were all sub-aerial except for Limulus. The order ranges Arenig through Permian and all four superfamilies are represented in Devonian time. Spitsbergen fossils (Stormer 1934) are thought to be limited to the Red Bay Group with: Pterygotus in the Fr~enkelrygen Formation, Bunaia, Eurypterus and the trace fossil Merostornichnites from the Ben Nevis Formation. These fossils are typically marine and occur only in marginal facies.

Merostomata.

Fig. 16.3. Devonian fossil fish reconstructions. Designed by WBH and drawn by J. Sibbick; reconstructions largely adapted from various sources in Moy-Thomas & Miles (1971).

294

CHAPTER 16 Or~loviciap

S urian

Early IMiddle] Late Early IMiddlel Late

Lok

Pra

Eros

Devonian Eif I Giv I Frs

F. . . .

Carboniferous Hol d later

Agnatha (Cyclostomata) Cephalaspidomorhi Osteostraci (5 orders of Cephalaspids) Anaspida (4 orders)

<--

Myxinoidea Hyenotreta Pteraspidornorphic Heterostraci (7 orders of Pteraspids)

4

'=

r

Theleodonti (2 orders)

j.-

Gnasthostornata Teleostomi Acanthoidii (3 orders)

-r

9

Osteichthes Actinopterygii (Chondostrei & Holostei) Crossopterygii (Rhipidistia & Actinistia) Dipnoi Elasmobranchiomorpha Placodermic

r

Chondrichthyes Elasmobranchii (3 Devonian orders)

7-

Holocephali (1 Devonian order)

Fig. 16.4. Devonian fossil fish ranges through time.

Ostracoda. A subclass within the class crustacea is manifested in a wide range of Paleozoic forms becoming abundant in Arenig times. Of approximately 36 families, 25 have a Devonian record but only a few forms are recorded with Svalbard's Devonian biota: Leperditia in Ben Nevis Fm; Isochilina, and Holtedahlina in the Stordalen Division of the Wood Bay Fm; Isochilina (8 spp.) and Paeniquina in the Grey Hoek Fm. and indet. form in the Wijde Bay Fm; Isochilina in Estheriahaugen Mbr.

structural variety of the early plant fossils, hence their limited biostratigraphic use until perhaps in Later Devonian strata. Plant material is evident in the sandstones of the Siktefjellet Group but lacks even generic identification. The plant fossil record of Spitsbergen is abstracted here from Friend's list of Spitsbergen Devonian fossils (1961), which was mainly based on Hoeg (1942):

Conchostraca.

Hostimella and Psilodendron from the Grey Hoek Formation; Cephalopteris, Drepanophycus, Hostimella and Psilophyton from the Wijde

Estheria in the Fiskeklofta Fm.

Hostimella, Pachytheca, Prototaxites, Taeniocrada and Zosterophyllum are recorded from the Fr~enkelryggenFormation;

Psilophyton from the Austfjorden sandstone of the Wood Bay Formation; Barinophyton, Bucheria, Hostimella, Platyphyllum and Psilophyton from the Mimerbukta sandstone also of the Wood Bay Formation;

Bay Formation; Mollusca (mostly bivalves):

Carditomantea, Cypricardina, Modio-

lopsis, Prosocoelus, Pterinea, in the Ben Nevis Formation. Avicula, Ctenodonta, Montaneria, Myalina spp. in the Grey Hoek Formation Undescribed bivalves and gastropods in the Wijde Bay Formation include Myalina. Kayser (1901) and Quenstedt (1926) described Grey Hoek molluscan faunas.

16.3.4

Devonian plants of Svalbard

(a) The Spitsbergen record.

Land plants: In the same way that Devonian fish are distinguished by their excursion from the sea into a continental situation so also the development of land plants, heralded in Silurian time is best seen in the Old Red Sandstone facies (Fig. 16.6). The material, however, is strictly limited by the smaller chance of preservation of soft tissues washed into streams and deposited fortuitously in lakes; also by the relative lack of

Actinopodium, Bothrodendron, Protaxites and spores from the Fiskeklofta (shale) Member and Lepidodendron, Bergaria, Platyphyllun from the Fiskeklofta sandstone Member;

Bergeria, Caulopteris, Dietyoxylon, Enigmophyton, Hyenia, Platyphyllum, Protoarticulata, Protopteridium, Svalbardia and spores, from the Planteryggen Sandstone Member; The Planteklofta Member yielded only indeterminate fragments.

Charopbytes: one genus Trochliscus indicating a fresh water environment is recorded from the Wood Bay Formation in several units and from the Grey Hoek Formation. The forms listed above represent a somewhat accidental record in a fluvial environment which mainly comprises Early and MidDevonian Psilophyta. The Late Devonian flora of Spitsbergen developed in a more propitious deltaic (coal measure) environment with distinctive plants heralding the rich Carboniferous vegetation. The Mimer Valley Formation is early Frasian. Allen (1965) described Devonian spores from north and central Spitsbergen.

DEVONIAN HISTORY

Svalbard units

Heterostraci (TheleodonU T)

Osteostraci

Placoderms Arthrodina Petalich Pt.

295

Acanthoidii

I Actinopterygii

I Crossopterygii

Rhadinichthys

Dictyonosteus Glyptslepis Onychodus Rhyzodontids Rhyzodontids

Antianchi Ac Petachi Pt

R~edvika Fm.

Psammolepis

I

Fiskekl~fta

? Huginaspis? Wijde Bay Estheniahaugen

I Psammolepis Psammosteus Pteraspids

]

Fm.

HolonamaAd AstenolepisAc

]

HeterostiusAd ?HolonemaAd ?HomosteusAd AstenolepisAc

Pteraspidomorphs I Acrotomaspis ?Cephalaspis

Grey Hoek Fm.

Stjerdalen Division

KeltiefJellet Division

Kapp Kjeldsen

Division

Sigurdfjellet Division

HeterostiusAd HomostiusAd HuginaspisAd MediaspisAd MonaspisAd LunaspisPt Amaltheolepis T I Parameteoraspis I Actinolepis Sigurdia T Diademaspis Heterogaspis Tusinia T Nectaspis Herasmius Doryaspis Gustavaspis Homosteus Amaltheolepis T I Parameteoraspis Arctaspis Arctolepis Doryaspis Diademaspis Actinolepis Spatulaspis Dicranaspis Nectaspis Hildenaspis Gustavaspis Arctaspis Doryaspis Macheriaspis Lataspis Zaseinaspis "Cephalaspis" Parameteoraspis Gigantaspis i Lehmanosteus Axinaspis Dicksonostius Boreaspis Elegantaspis Austomaspis Heintzostius Spatneaspis Dineraspis Nectaspis Paleocanthaspids Amaltheolepis T I Machariaspis Sigaspis Sigurdia T I "Cephalaspis" Arctaspis Turinia T Benneviaspis Doryaspis Parameteoraspis Zascinaspis Norselaspis Gigantaspis Axinaspis Belonaspis Diademaspis Nikolivia T Parameteoraspis Turunia T Zenaspis Apalolepis T Scolenaspis Doryaspis Hoelaspis Irregulariaspis Kieseraspis Weigeltaspis Brenneviaspis Crenaspis Tegaspis Lavnovaspis Secuniaspis Mietaspis Mimetaspis Canadapteraspis Cephalaspis Homalaspidella Machieraspos Anglaspis Depidaspis Poraspis Protopterspis Corvaspis

Sva/bardaspis

Anglaspis Homaspidella Anglaspis Dinaspirella Poraspis Protopteraspis Corvaspis Traquaiiaspis Corvaspis Trachanaspis Davelaspis

I Wengsjoeaspis Ectinaspis "Cephalaspis" Paltenaspis Machieraspis Cephalaspis

Atopocanthus

Atopocanthus

Atopocanthus

Porolepis Onchyodus

Onchus Xylacanthus

Porolopis

Nostolepis Gomphoncus Onchus

Porolepis

Nostolepis Protodus Gomphonchus Onchus

Nostolepis

I Cephalaspids Modainaspis Aflthodines

Andreebreen Fm. I Pteraspids I Psammosteids Rivieratoppen Fm

I Anglaspis Protopteraspis

Fig. 16.5. Distribution of Svalbard Devonian fish genera with time, abstracted from Friend (1961) and for the Rivieratoppen Formation from Ilyes (1994) and Ilyes, Ohta & Guddinggsmo (1995).

296

CHAPTER 16

Fig. 16.6. 'A later Devonian landscape', drawn by Mr Edward Vulliamy to illustrate the flora based partly on Svalbard data, reproduced from A. C. Seward (1931) Plant Life through the Ages, fig. 48, p. 141. Cambridge University Press. Spores. Early and Mid-Devonian spores from Central Spitsbergen were investigated by Allen (1965, 1967, 1973). He reviewed Late Silurian and Devonian spores in a global survey (1980). From detailed tables of Spitsbergen occurrences (1967) he tabulated 56 species and their occurrence in three assemblages: culpa (Mid- and Late Siegenian-Pragian), eximus (Emsian, Eifelian) and triangulatus (Givetian). Most occurrences were in north Dickson Land and very few in Andr6e Land. (b) The Bjornoya record. After the interval of the Svalbardian tectonism, which must have modified Laurentia's geography, the lower part of the Roedvika Formation yielded an internationally recognised Late Devonian (Late Famennian) flora. The deltaic environment persisted into the Early Carboniferous coal measures. New taxa are depicted in Seward (1931, fig. 48, p. 141). These are based on the researches of Nathorst (e.g. 1900) (see Fig. 16.6).

Lycopodiales include: Cyclostigma (Cy), Protolepidodendron (Pn), and Leptophoeum (L); Protoarticulatae include: Pseudobornia (Pb) and Sphenophyllum (Sp); Pteridospermae include Archaeopteris (A), Cephalopteris (Cs) and Sphenop teridium (Sin). 16.4

?Silurian and Devonian sedimentation

The classification of the units follows that in Fig. 16.2 and details of the units and their history are recounted in the regional chapters 8 10 and 11. The Late Silurian to Devonian sedimentation pattern in Svalbard is summarized in Fig. 16.7.

16.4.1

SiktefjeUet and Red Bay groups sedimentation (Friend et al. 1997) Siktefjellet Group

Rabotpasset Conglomerate Formation is a basal breccia followed by ill-sorted angular deposits which appear to have formed in at least two local basins as a result of debris-flow transport. Boulders of gneiss up to 2 m diameter rest on the metamorphic basement. This episode was followed by local compressive folding which consolidated tectonized deposits.

Lilljeborgfjellet Formation conglomerates followed, being deposited in two basins forming the 400m thick sequence on Lilljeborgfjellet itself, and the thinner, 50-100m sequence on Siktefjellet.

Albertbreen (sandstone) Formation was deposited in the Siktefjellet basin which subsided locally to 1400m probably with a pull-apart origin. The bulk of the formation consists of fluvial sand deposits characteristic of braided river flow with finegrained, siltstone and mudstone interbeds up to 20m thick that probably formed in overbank flood plains. Some ripple patterns may indicate ephemeral lakes. It contains both K-feldspar and plagioclase grains in abundance and less quartz (Gjelsvik & Ilyes 1991). Red Bay Group

DEVONIAN HISTORY

297

Fig. 16.7. Schematic diagrams to illustrate successive sedimentation patterns through Devonian time. The dashed lines on the coastlines imply that the land represented was not there at the time. Main faults: BBF, Breibogen Fault; RFF, Raudfjorden Fault; BFZ, Billefjorden Fault Zone. Adapted and updated from early unpublished figure by P. F. Friend.

Rivieratoppen Formation. Konglomeratodden (polymict conglomerate) Member is generally the initial Red Bay conglomerate unit, as seen most accessibly at Konglomeratodden. It developed as sheets of coarse, unsorted conglomerate suggestive of fluvial deposition, interspersed with

mudflows. Composition varies increasingly upwards suggesting successively deeper erosion at source; seldom from the underlying formation. The succeeding Wulffberget (marble conglomerate) Member is perhaps the most distinctive and conspicuous lithology in the two groups seen conveniently at Konglomeratodden and

298

CHAPTER 16

Rivieratoppen in Raudfjorden and by the shores of Liefdefjorden. It occurs in one to ten metre sheets with sandstone interbeds or merely a change of clast size. Most clasts are of one marble type with either carbonate or siliciclastic detritus as matrix. Some are cohesive flows and even with coherent rafts in the flow. Megaclasts range up to 4 m in diameter which suggests a local derivation. In coastal outcrops north of Liefdefjorden the conglomerate may be seen merging via massive breccia into fissured marble of the basement. Transport is unlikely to have been more than 2 km. Rivieratoppen Formation conglomerate composition should reflect the nature of eroding uplands (Holtedahl 1926). Harland (1960) noted the predominance of psammitic compositions amongst the metamorphic clasts and an absence of feldspathic clasts, whether migmatic or magmatic, in the Wulffberget Member. This suggested that those facies, presently occupying the whole of the terrane west of the Raudfjorden Fault, were either not then exposed or were elsewhere or both. However, feldspathic clasts are found in the underlying Konglomeratodden Member especially near the Raudfjorden Fault. The high energy conglomerates may be interspersed with thin fine-grained lacustrine deposits as also in the succeeding Rabotdalen Member (of the Andr6ebreen Formation).

Andr6ebreen Formation. Gjelsvik & Ilyes (1991) in a definitive petrographic and biostratigraphic study made at least four distinctive contributions. (i) The formation extends south of Liefdefjorden between the Hannabreen and Breibogen faults as far as Bockfjorden and can be distiguished e.g. by a general lack of potash feldspar, little plagioclase and by a distinctive new Andr6ebreen Formation fauna thus limiting the Siktefjellet group to outcrops north of Liefdefjorden (contra Gee & Moody Stuart 1966). (ii) The formation is generally fossiliferous with fish faunas. The facies includes thin lenses of 'peloid conglomerate' (with carbonate intraclasts and fossil fragments) which are interpreted as forming in a marine tidal basin where wave action mixed products of detrital, biogenic and biochemical activity. (iii) The westernmost outcrop at the head of Liefdefjorden is rich in feldspathic material as though derived from erosion of a terrane to the west of the Raudfjorden Fault. (iv) The Andr6ebreen Formation (south of Liefdefjorden) has few plagioclase clasts and no K-feldspar in contrast to the Siktefjellet rocks to the north which have low quartz and much K- and plagioclase feldspar. The Buchananhalvoya (sandstone) Member (which includes the above development) is the principal facies of the Andr6ebreen Formation, formed in a braided river environment. It interdigitates laterally with the Princesse Alice (quartz pebble conglomerate) Member of the same formation. Clasts are generally less than 5 cm, but up to 15 cm, in a sandy matrix. The grain size varies between a breccia and a pebbly sandstone. The facies suggests deposition from flashy river flows in high gradient bajadas at the foot of a mountain front. A change in clast composition upwards indicates a progressive erosion of the source where carbonates were eliminated from a psammitic core. The Rabotdalen (mudstone) Member was probably deposited in lakes beside the river courses. Up to this point sedimentation reflects repeated emergence of cliffs as erosional sources. These may be best explained by the hypothesis of sedimentation in a zone of strike-slip faulting with occasional transpression and transtension producing intermittent and sporadic fault scarps. Gjelsvik & Ilyes (1991) had suggested that the Psammostrateus horizon belonged to the upper part of the Andr6ebreen Formation (Buchananhalvoya Mbr). Ilyes, Ohta & Guddingsmo (1995) reported a still older find in Hesteskoholmen (horse-shoe island) in Liefdefjorden in a sandstone parting in the Wulffberget marble conglomerate member of the Rivieratoppen Formation. This is now the oldest dateable fossil record in the Liefde Bay Supergroup. It comprises the cyathaspid Anglaspis gjelsviki and the pteraspid

Protopterasps micra. These forms appear best to correlate with the Lochkovian Anglo-Welsh pococki zone. Ilyes et al. concluded that this and the higher Psammosteus horizon were fairly close in time and that their extensive stratal separation is due to high sedimentation rate. The Haakonian diastrophism, first proposed to separate the newly distinguished Siktefjellet Group from the long recognized Red Bay Group (Gee 1972) may now be modified to refer to the intermittent mobility in a strike-slip fault scarp environment through Siktefjellet time to at least the end of the Andr6ebreen Formation deposits in Red Bay time. This later limit is constrained by the thrusting, west of Hannabreen Fault, of Andr6ebreen sandstones.

The Framkelryggen Formation has rich fossiliferous horizons which also indicate a Lochkovian ( G e d i n n i a n ) age (i.e. still within the earliest Devonian stage). From then on, deposition of the Fr~enkelryggen and Ben Nevis Formations of the Red Bay Group was less confined or tectonically controlled and so displays more extensive and uniform facies. Fr~enkelryggen Fm sedimentation was of fluvial type with red mudstones of river flood plain overbank origin divided by river channel sheet sandstones typically of 15 m thick fine sand. Flat bedding with lineation, cross-bedding and small ripple structures represent different flow stages in the channels. Lenticular calcareous intraclast pebble conglomerates include vertebrate fragments. Molluscs and merostomes suggest some marine influences. The salinity environment in which the fish lived is still a question.

The Ben Nevis Formation, still within the Lochkovian stage, suggests similar development. It is likely that the Red Bay Conglomerates and the Ben Nevis Formation extended somewhat eastwards of the Breibogen Fault because of the Vonbreen outcrops northwest of Holtedahlfonna (Foyn & Heintz 1943). Red Bay Group to east of Breibogen Fault. Hoel (1914) reported a locality with Red Bay Conglomerates on the south cliff of Sigurdfjellet, facing the northern side of the lower Vonbreen (Hoffnung Glacier). This occurrence was described by Foyn & Heintz (1943) and is of interest as the only reported Red Bay Group outcrop east of the Breibogen Fault Zone. Up against the fault is a 'red brown coarse conglomerate without any distinctive stratification. It consists of quartzite and gneiss'. We refer to this informally as the Vonbreen Conglomerate. To the east, referred to in Chapter 8.3.1, and lacking connecting exposure, is a greyish-green sandstone with Pteraspis and Hornaspis which correlates with the Ben Nevis Formation of the Red Bay Group further north. This Vonbreen sandstone underlies fossiliferous red strata of the Kapp Kjeldsen Division, low in the Wood Bay Formation. If the biostratigraphy is good we have also the only known direct stratigraphic sequence between the Red Bay and Andr6e Land groups. McCann (1996), however, postulated a basal Wood Bay unconformity relating to his Monacobreen folding phase on structural mapping evidence and this locality is the only sedimentary expression of it.

16.4.2

Wood Bay Formation sedimentation (Pragian and Emsian) Late Early Devonian

Wood Bay is the most extensive Devonian formation, it was the focus of a comprehensive sedimentological study by Friend & Moody Stuart (1972). They envisaged an intermontane flood plain environment and fossils in the siltstones require a coastal setting with marine incursions. Red colour and carbonate concretions suggest a level above the water table. Moody Stuart had shown that the coarse elements of the cyclothems were deposited from meandering and low sinuosity rivers, generally succeeded by fine red overbank siltstones. Reed (1991) also described the calcretes. Analysis of palaeocurrents, sandstone composition and grain size distinguished three river systems which flowed towards a

DEVONIAN HISTORY northern area of clay deposition. The eastern river system was large, flowing N to NNW, and of a high bed load or braided type. The sand-grade sediment was rich in feldspar. In contrast, those of the western system were small, east-flowing, mixed or suspendedload rivers of high sinuosity and carrying less sand grade and less feldspar. The central system flowed north, parallel to the trend of the basement folds and was otherwise similar to the western system. The Austfjorden sandstone facies member to the southeast of the basin contains small pebbles. This coarsening of sediments to the southeast could herald the northward arrival in the south of higher ground east of the Billefjorden Fault Zone. To the three faunal divisions already in use Goujet (1984) added a fourth, Sigurdfjellet Division, to precede the others, thus: Stjordalen Division, 400 m Emsian Keltiefjellet or Lykta Division, 600-900 m Pragian-Emsian Kapp Kjeldsen Division, 1000-1500 m Pragian Sigurdfjellet Division. To the southwest (near the mountain Pretender), the Lykta Division overlaps older Devonian strata to step directly on pre-Devonian metamorphic basement.

Lower Marietoppen Formation (in southern Spitsbergen). The fine grain-size, lack of high energy sedimentary structures, and high limestone content suggest a more distal position in the alluvial transport system. Proximity to the sea is indicated by incoming of molluscan faunas. Friend & Moody-Stuart (1972), already favourably disposed to the Late Devonian strike-slip hypothesis for the Billefjorden Fault Zone, suggested that this Middle Hornsund terrane could have been located northwest of Andr6e Land in Wood Bay times.

16.4.3

Mid-Devonian sedimentation

Grey Hoek Formation (Eifelian-early Mid-Devonian). Friend (1961) postulated a marginal marine, brackish water, intertidal environment with possibly neap tide desiccation cracks. Worsley (1972) attributed the sandstones to fluvial action suggesting a broad coastal swamp, with shallow lagoons into which a meandering river complex flowed, probably largely cut off from the sea by barrier islands. Palaeocurrents indicate predominant flow to N E and ENE. However the rocks are strongly folded with axes parallel to ripple crests. Middle and upper Marietoppen Formation are similar to the lower division and have been correlated with the Grey Hoek Formation. Wijde Bay Formation (Givetian Late Mid-Devonian). The combination of marine molluscan and non-marine faunas, coupled with a silt-shale-sandstone sequence, suggests coastal intertidal, partly brackish water deposition. The trend towards a greater proportion of sandstones upward may reflect the build-out of a sediment body into the sea. Cross-stratification indicates currents flowing to the NNE. Mimer Valley Formation. The eastern development indicates fresh water, fluvial and lacustrine environments, with cannel coal in Mimerdalen (Horn 1941) and oolitic ironstone on the Caiusbreen/ Hoelbreen col (Friend) with a paleoslope towards the western and northern developments. The molluscan fauna of which is evidence of brackish water conditions. However, there is no record of paleocurrent indicators. These areas could have drained towards the Grey Hoek and Wijde Bay intertidal environments further north. The topmost conglomerate member gives the first significant warning of renewed diastrophism (of the Svalbardian episode). The upper members of the Mimer Valley Formation could be Frasnian (Late Devonian in age).

16.4.4

299

Late Devonian-Famennian sedimentation

Roedvika Formation (Famennian) in Bjornoya. This continuity of sedimentation into Tournaisian time suggests that, if the Svalbardian diastrophism was widespread, it preceded this late Famennian sedimentation, i.e was Late Frasnian-early Famennian. It heralds the new coal measure facies of the Billefjorden Group which only develops in the Mimerdalen area in early Tournaisian time. Not only is the Famennian-Tournaisian facies approximately continuous in Bjornoya but also in the Billefjorden Trough. The Horbyebreen Formation, until recently regarded as wholly Tournaisian may also have been initiated by Famennian sedimentation (van Veen pers. comm.).

16.5

Devonian tectonics

Because some uncertainty has been expressed as to which structures were Devonian and which later, i.e. Paleogene, the structures are described and then discussed. The main N N W - S S E faults divide the study area into subterranes which will be considered in order from west to east. Although the terms 'graben' and 'horst' have been widely used for many of these subterranes, we use the terms 'basin' and 'high' here to avoid any genetic or geometrical connotation.

16.5.1

Albert I Land High

The northwest part of Svalbard west of the Raudfjorden Fault (RFF) is a unified province comprising pre-Devonian metasediments and related igneous rocks; the general trend of lithological boundaries and structural fabrics is NNW-SSE. The main deformation and metamorphism was Silurian; but differential uplift, cooling and erosion at least were Devonian. Hjelle (1979) subdivided the region into four areas on the basis of broad geological relationships: (i) (ii)

the southern area (predominantly metasediments); the central and northern gneiss and migmatite area (highgrade metamorphics intruded by a post-tectonic batholith); (iii) the western transition area (predominantly metasediments at higher grade than area (i), forming a strip along the western flank of area (ii) and towards which grade increases); (iv) the eastern transition area (predominantly metasediments at higher grade than area (i), forming a strip along the eastern flank of area (ii) and towards which grade increases). The overall structure of the region is described as an 'anticlinorium' plunging gently to the SSE. Deeper structural levels are therefore successively exposed towards the centre and north. Polyphase deformation affects the metamorphic rocks in the northwest region. Significant progress has been made towards identifying different deformation phases using their associated fabrics and minor structures; the broad structural relationships of different rock units have also been established (Gee & Hjelle 1966; Hjelle 1979). However, identification, relative dating and correlation of major structures throughout the region is hampered by: (a) a lack of way-up criteria and distinct marker horizons in the metasediments; (b) the homoaxial nature of the principal fold phases; (c) the loss of stratigraphic coherence in the migmatites; and (d) the sparsity of age determinations. It is perhaps indicative of the present stage of knowledge that, although Gee & Hjelle (1966) and Hjelle (1979) erected a succession and described a complex structural history, their maps, sections and stereographic projections present only lithologies and undifferentiated structural elements. The following account of the structure is based on the tectonic history proposed by Hjelle (1979). Structural relationships are simplest and clearest in the metasediments of the south and become increasingly obscure in the higher-grade rocks north and south; pelitic lithologies in the south have therefore provided most of the information. At least three fold phases have

300

CHAPTER 16

been identified of which the majority of minor and major folds belong to F2. Thrusting appears to be associated with F2 and both thrust and fold geometry indicate vergence towards the west. Hjelle (1979) assigned F2 to the main mid-Silurian Caledonian event occurring at lower to upper amphibolite facies. Gee & Hjelle (1966) and Hjelle (1979) concluded that peak metamorphic conditions predated F2 in the south according to their interpretation of garnet textures. This metamorphic event, associated with F1 folds, was at upper amphibolite facies and occurred between late Proterozoic and early Paleozoic. However, evidence of an F2 fabric in the palaeosome of the migmatites indicates that migmatization postdated F2. Migmatization at deeper structural levels may not be synchronous with peak metamorphism at higher levels. Those events would probably be Silurian and the following events might be Devonian. The overall 'anticlinorium' structure of the northwest region is described as 'late' and is assumed by Hjelle (1979) to be related to the F3 migmatization. However, this structure may not be the result of a specific tectonic event, and could just be the geometric consequence of other events. Some NNW-SSE trending faults north of Kongsfjorden, with a downthrow to the west, occur on the western flank of the anticlinorium and Hjelle (1979) considered them to be associated with its development. This author, however, is not satisfied that there is an unambiguous case for Silurian westerly vergence. It is certain that some instances of westerly vergence are Devonian and possibly others. The anticlinorium structure is complex, there are instances of apparent easterly vergence. Ohta (1969) emphasized the effect of emplacement of granite in oblique structures superimposed on earlier structures. Emplacement of the Hornemantoppen intrusion occurred during the last phases of ductile deformation; the intrusion was dated at 4 1 4 + 1 0 M a (Rb-Sr) c. Lochkovian and at 413Ma by Balashov et al. (1996) c. Wenlock-Llandovery. Movement on the major west-directed thrust between Lillieh66kbreen and Smeerenburgfjorden is assumed to be related to granite emplacement by Hjelle (1979).

16.5.2

Mitrahalvoya

Attention was drawn to the NNW-SSE-trending fault on Mitrahalvoya with downthrow to the east shown on the map of Hjelle (1979), and to the observation in the same paper that red staining in the area suggested an exhumed Devonian unconformity. By analogy with the Blomstrandhalvoya-Lov+noyane Basin (Section 5.1.2) this could represent the former position of another small elongate basin. It is separated from the BlomstrandhalvoyaLov6noyane Basin by a distance of approximately 15 18km, perpendicular to the trend of the faults, and appears to be a small scale analogue.

16.5.3

Blomstrandhalvoya-Lov~noyane Basin

Blomstrandhalvoya (with the classic marble locality at the aborted London mine) is mainly formed of the Generalfjella Formation marbles disposed in an open synform. This formation is also exposed to the south on some of the islands of Lov~noyane. The remaining islands, however, are composed of locally derived red conglomerates, and grey-green sandstones, shales and pebble conglomerates (Gjelsvik 1974). These sediments are unmetamorphosed and are said to contain fossils suggesting Early Devonian age; they therefore closely resemble the Devonian sediments of the Raudfjorden area both in age and lithology. The Devonian sediments of the Blomstrandhalvoya-Lov6noyane Basin can be traced inland as far as Fortende Juliebreen as a narrow NNW-SSE trending outcrop (Fig. 8.1). Some confusion is apparent concerning the structure in which they lie. Gjelsvik (1974) suggested a narrow graben bounded by steep faults which are observed as shear zones in two localities and interpreted elsewhere from submarine topography. The 1:100 000 map, 3G, of Hjelle & Lauritzen (1982), however, shows the western fault as a thrust with marble apparently thrust over Devonian sediments from the west. Later work by Thiedig (1988) and Thiedig & M a n b y

(1992) described a Devonian N - S graben on Blomstrandhalvoya. The boundary faults of the graben are systematically overthrust to the west as are other thrusts and some asymmetric folds in the marble. It is therefore likely that the deformation was Devonian because the Paleogene thrusting south of Kongsfjorden verged to the NE. The deformation could be Haakonian or Svalbardian (Early or Late Devonian). To the east, the islands in Kongsfjorden show similar relicts of a N - S graben system as illustrated in Fig. 8.8.

16.5.4

Raudfjorden Fault (RFF)

A NNW-SSE-trending fault along Raudfjorden, Monacobreen and Isachsenfonna has appeared on most geological maps of Spitsbergen since Nathorst (Suess 1888). It is approximately parallel to the tectonic grain of the Krossfjordian structures which no doubt influenced its trend. It appears to cut neither Wood Bay nor Carboniferous strata south of Kronebreen (Fig. 8.1), although some maps (e.g. Dallmeyer et al. 1990) connect it with the Pretender Fault which juxtaposes Devonian and Carboniferous strata. At Konglomeratodden (east of Raudfjorden) metamorphic rocks to the west are faulted against the Rivieratoppen (conglomerate) Formation to the east. A straight fault-line is traced to the south, tangential to other promontories west of Raudfjorden. After a 2 km offset to the east in Idabreen, a straight line can be traced to the south through Monacobreen separating metamorphic rocks to the west from the Rivieratoppen (equivalent) formation to the east Fig. 8.1. This offset is matched by others displacing the Breibogen Fault. It trends SE from a similar sinistral displacement of the Hornemantoppen Batholith. These lateral sinistral displacements are consistent with the effects of the Paleogene West Spitsbergen Orogeny away from the thrust front. Possibly further support for this relationship might be provided by A. McCann's mapped thrust front east of Monacobreen (pers. comm.). This would fit well Paleogene but not Devonian tectonics.

16.5.5

Biskayerfonna-Hoitedahifonna Terrane

As introduced in Chapter 8 this terrane extends in a narrow N - S strip between the Raudfjorden and Breibogen faults. It comprises an elongated basement high and a cover sequence mainly of Red Bay Group conglomerates and sandstones. In general, the antiformal metamorphic basement extends along the eastern side of the terrane. The synformal Red Bay strata occupy the western outcrop where it is not obscured by Raudfjorden in the north, by the head of Liefdefjorden and then south of Liefdefjorden by the large glacier Monacobreen. This simple structure is complicated in the north by the oblique Hannabreen Fault trending N W - S E and joining the Breibogen Fault near Bockfjorden. East of this fault and only north of Liefdefjorden the Siktefjellet Group rocks are exposed and strike discordantly to younger rocks both north and south of Liefdefjorden. These structural features were established, amongst others, by Gee & Moody-Stuart (1966), Gjelsvik (1979) and Burov & Semevskiy (1979). The following interpretation is based on a renewed study (from 1989 to 1992) by Friend et al. (1997) north of Liefdefjorden, and by Piepjohn & Thiedig (1992) immediately south of Liefdefjorden. It is thought to be consistent with field work further south along Monacobreen to Holtedahlfonna by A. M c C a n n (pers. comm.). This interpretation combines sedimentological analysis, especially the derivation of widespread proximal conglomerates and breccias with structural data on both the cover strata and on the boundary faults. In short, the conclusion of Friend et al. was that recurrent strike-slip on the boundary faults caused repeated fault scarps at intervals throughout the terrane so providing local conglomerates, especially derived from the widespread marbles at the top of the basement succession. The strike-slip could have been accompanied by episodes of transpression causing folding and local thrusting, and episodes of transcurrence or transtension when normal

DEVONIAN HISTORY sedimentation from a large river system in a subsiding (Raudfjorden) basin prevailed. This model would entail the major faults being generated from Silurian (Caledonian) compression leading through transpression to transcurrence because of the their straightness and parallelism to the basement fabrics. The kinematic sense was sinistral. For the whole terrane to be subjected from time to time to sinistral transpression, movement on the Breibogen Fault would have exceeded that on the Raudfjorden Fault. Gee & Moody-Stuart (1966) demonstrated an unconformity between the Siktefjellet and Red Bay groups, and Gee (1972), who was the first to note sinistrally deformed structures in the area, identified this unconformity as a product of his Haakonian movements. Friend et al. concluded that the movements occurred from early Siktefjellet Group time as seen in the Rabotpasset Formation right through to Andr~ebreen Formation time and so suggested extending the Haakonian concept to range from ?late Silurian through early Lochkovian time. In spite of the observations depicted by Piepjohn & Thiedig (1992) of steep dips, westward verging thrusts and some oblique sinistral strike-slip faults in their structural profiles, Piepjohn & Thiedig (1994) interpreted a wider sequence of events in a longer time span only as Early Devonian extension and subsidence and Late Devonian compression. Where the pre-Devonian basement structure was described (Fig. 15.5) it is eastward verging. The Hannabreen Fault would also be a strike-slip splay of the Breibogen Fault, but with less movement, and not active after Andr+ebreen Formation time, unlike the Breibogen Fault. The structural effect of this fault is that it bounds the Siktefjellet Group and the basement outcrop on the west. South of Liefdefjorden it juxtaposes the wedge of Andr~ebreen Formation against basement on the west which is cut out completely where it joins the Breibogen Fault. At intervals along its straight trace the fault can be inferred as near-vertical. Northwest of the glacier snout (Borrebreen) patches of mylonitic fabric with sub-horizontal lineation may be seen. A small degree of minor strike slip may be inferred. The Devonian strata in a synclinal structure (Gee 1966), which is at least partly tectonic in origin (Burov & Semevskiy 1979), has been mapped south of Liefdefjorden by McCann (pers. comm.), who argued that, in his Monacobreen Phase, it was folded with the metamorphic antiform in latest Red Bay Group and/or earliest Wood Bay Formation time.

16.5.6

Breibogen Fault (BBF)

The BBF is parallel to the R F F and resembles it in that it does not appear to affect Wood Bay Formation strata to the south of Holtedahlfonna. The fault zone is accessible from the sea on the cliffs and mountains south of Breibogen. Near the shore a breccia of large red sandstone blocks of Wood Bay facies suggests syn-depositional movement. The fault line can be seen as a straight boundary running south between red colours on the east and dark grey on the west. This is a most obvious normal fault with some syndepositional activity. However, in the metamorphic terrane to the west there are indications of mylonitic textures up to half a km away from the fault line, and more concentrated nearer the fault where the rocks as a whole are somewhat dislocated. Some subhorizontal slickensiding may be seen in situ. North of Liefdefjorden against a normal east-dipping fault Wood Bay Formation strata, with a gently east-dipping regional homocline (5~ dip more steeply as they approach the fault. Sporadic conglomerate in the Wood Bay Formation near the fault suggests some tectonic activity during deposition. On Fotkollen, immediately to the west of the fault, is a zone (150m wide) of shattered sandstone coarser than the normal Wood Bay Formation and suggestive of a Red Bay Group sandstone facies. West of this zone is a zone of shattered pelitic and psammitic schists. Fragments showing a marked lineation, but in situ rocks were not accessible to establish orientation. Further west typical psammitic (to pelitic) schists occur. About 2 k m to the south, on Siktefjellet, the Wood

301

Bay Group strata appear to be faulted directly against dense (indurated?) Siktefjellet Group quartzites. Some loose blocks show mylonitic texture which is itself brecciated, but these rocks were not located in situ. With an inferred 2 km offset to the east, the BBF resumes its course from Liefdefjorden south to Bockfjorden where Siktefjellet Group sandstone to the west is faulted against Wood Bay Formation to the east. South of Bockfjorden, the fault zone is associated with the Quaternary volcanic cones of Sverrefjellet, Halvdanpiggen and Sigurdfjellet (Gjelsvik 1963; Prestvik 1978) (see Chapter 8). The fault continues southwards to Holtedahlfonna, south of which the Wood Bay Formation is mapped as overstepping and overlapping older rocks across the extrapolated line of the fault. Nevertheless, some authors (e.g. Dallmeyer et al. 1990) link the N-S faults in Ekmanfjorden with this line and thus indicating post-Carboniferous (?post-Paleocene) rejuvenation of an older buried fault. From the above observations and the straight trace of the fault an early strike-slip history is inferred inducing the location of subsequent normal faulting. The sinistral sense is better seen in the minor structure of the neighbouring metamorphic rocks. The history would be late Silurian through Lochkovian and the dip-slip would be Lochkovian to Pragian with possibly renewed strike-slip associated with the Monacobreen Phase.

16.5.7

Andr6e Land-Diekson Land Terrane

The structure of this terrane, clearly defined between the Breibogen and Billefjorden Faults, is outlined in Section 8.5.2 and partly schematically illustrated in Fig. 16.8. Conclusions as to its evolution are summarized thus. (i) There is sufficient N-S continuity of structure through the whole terrane to conclude that the Svalbardian deformation, which is of demonstrable Late Devonian age in the south, applies throughout. (ii) The intensity of deformation is greatest in the east and is generally least in the west. This suggests that the Svalbardian stresses that led to deformation were somehow generated in the east and through the N-S length of the terrane. (iii) This is supported by many instances of asymmetric folds and thrusts with westward vergence. (iv) An E - W traverse shows that N-S zones of more intense deformation alternate with zones of weaker deformation which may suggest concentration of deformation over fault zones in the deeper basement. (v) A N-S traverse shows that individual folds are not continuous but plunge between others. It is not clear to what extent there is some systematic cross-folding. (vi) the folding and thrusting while generally trending N-S is by no means homoaxial. Whether or not fold axes appear occasionally in en 6chelon formation there is sufficient divergence from the trace of the Billefjorden Fault Zone for slightly oblique axes to be consistent with sinistral transpression. This was the impression of the author in 1951 and on other occasions of P. F. Friend in the course of different investigations. Piepjohn & Thiedig (1992) published data on folds from Andr6e Land with data on plunging axes consistent with sinistral transpression. In their 1994 paper, however, transpression whether here or further west appears not to be considered by them. More detailed surveys are needed. They might support the transpression hypothesis; they could not refute it.

16.5.8

Billefjorden Fault Zone (BFZ)

This fault has long been recognized as an major feature of Svalbard geology; for example, it appears on the map of Nathorst (Suess 1888) (Fig. 2.1). The fault zone trends in a straight line (NNW-SSE) running the length of Wijdefjorden, along Billefjorden and across Sassenfjorden.

302

CHAPTER 16

J

N

J

f

J

1 km

/7

ORSABREEN FAULT z

C)

I . . . .

G R O N H O R G D A L E N BALLIOLBREEN BELT FA U LT ..

- ,

DICKSON _JORD ~

I DICKSON LAND I , , / ' - - _ --'~'~"~------~ ~

10 Km

WEST 1

km].

EAST i

Fig. 16.8. True-scale, isometric cross-sections of fold and fault zones in the Devonian rocks of (a) the Gronhorgdalen Belt and (b) the Eastern Boundary Belt in eastern Dickson Land and (c) an E-W cross-section from James I Land to the Balliobreen Fault in Dickson Land; from original observations by P. F. Friend 1955 to 1965. The principal fault exposed in the zone (the Balliolbreen Fault) can be seen between Wijdefjorden and Billefjorden where several other faults to east and west occur. Indeed, the name BFZ is given to a zone of deformed Liefde Bay Supergroup rocks to the west and Hecla Hoek rocks to the east. It can also be shown to continue beneath, and to affect post-Devonian cover rocks (Harland et al. 1974; McCann & Dallmann 1996). Between Wijdefjorden and Billefjorden, the Cambridgebreen Shear Zone of metamorphosed Hecla Hoek rocks is exposed and is seen to have retrogressed from amphibolite to greenschist facies in the zone 2-3 km wide (e.g. Harland 1985), with mylonites evident in western Ny Friesland (Manby 1990). Other structures in the Hecla Hoek rocks suggest a long and complex pre-Devonian tectogenesis. This wide zone is evidence of considerable shear displacement and under a far smaller overburden than the main Silurian orogenic transpression which is evident in western Ny Friesland where high grade minerals indicate say 20 km of overburden. Whereas the Ny Friesland structure shows the oblique compression that originated the transpression concept, the chloritic shear zone is interpreted as a later transcurrent zone. It could be in part the strike-slip component corresponding to the compressive thrusting and folding seen in Devonian strata to the west, albeit with some evidence of oblique fold axes. The original argument for Silurian transpression allowed for partitioning of components of transcurrence and compression (Harland 1971). This argument is for such partitioning of transpression in late Devonian time as well as for pure strike-slip. On the western side, the 'eastern boundary belt' is located southwest of Austfjorden and northwest of Billefjorden and can be traced for approximately 70km. Slickenside lineations indicating dip-slip movement are abundant in the Devonian rocks, and the

thickness of Devonian rocks brought down to the west gives the zone a minimum dip-slip displacement of 2000 m (Harland et al. 1974). Large-scale mapping shows complex folds and faults to be present in the Devonian rocks, which are overlain by relatively undeformed Carboniferous (Tournaisian) strata. The pre-Carboniferous folds are tight and asymmetrical or overturned to the west adjacent to the fault zone, but they become open and upright further west. The Balliolbreen Fault is a reverse fault, dipping 60 ~ east, with associated structures characteristic of a thrust system (McWhae 1953). Lamar, Reed & Douglass (1986), who described the structure of the area, recorded both some sinistral and dextral reverse oblique-slip and some horizontal dextral slickensides on the Balliolbreen Fault. Their map (simplified as Fig. 8.10) shows a complex fault and fold system which they interpreted as a compressional rather than strike-slip structure. Further to the south, where Devonian rocks are covered by Carboniferous through Triassic strata, Faleide et al. (1991) depicted (in their seismic line D) a profile running ENE through Isfjorden and across the projection of the Billefjorden Fault Zone (BFZ). This shows i.a. a near vertical BFZ with 11 to 12kin deep basin above basement to the west of it and less than 2 km to the east. F r o m surface mapping the eastern cover rocks are known to be Carboniferous and Permian, which strata thin westwards across the fault above the Nordfjorden Block. Thus, at this latitude the Nordfjorden Block comprises not less than 10km of Devonian strata above basement. These thin to (near) zero thickness between 25 and 40 km to west of BFZ. It looks like a basin truncated sharply by a vertical fault. The profile also gives evidence of eastward verging thrusting related to the West Spitsbergen Orogen, but no suggestion of westward thrusting at the BFZ. Taken at its face

DEVONIAN HISTORY

value it is a cross-section of a major strike-slip fault affected during and/or after the main Devonian basin deposition and before the Tournaisian (and? late Famennian cover). 16.6

16.6.1

303

WESTERN

The conjecture here is that through Ordovician-Silurian-Devonian time in Svalbard (and more generally in the Caledonides) sinistral strike-slip moved eastern Svalbard northwards with respect to central and eastern Svalbard, and with respect to Greenland, over distances which added up in all fault zones, and through the whole time span, to more than 1000 km. Associated with simple strike-slip (or transcurrence) were transpression (oblique compression) and transtension (pull-apart) regimes. In addition to minor faults there were major fault zones separating distinct terranes originating as distant provinces which were finally brought together in Late Devonian time so forming the pre-Carboniferous basement of Svalbard as we know it. This is a mobilist view. The fixist antithesis is that, at least within Svalbard, the elements of the pre-Carboniferous basement occupied their present relative positions (at least within 100km or so) back to Neoproterozoic time or earlier. From this view stems the widespread reference to all pre-Devonian rocks in Svalbard as Hecla Hoek and the attempt to recount their history as though, through that long time span, they were related approximately as now. Geologists of both tendencies must now accept the mobilist interpretation that Svalbard as now constituted moved to its present position from north of North Greenland through Cenozoic time. Apart from suspicions about strike-slip (e.g. McWhae 1953 with reference to the Billefjorden Fault Zone), a fixist opinion with respect to relationships within Svalbard was generally assumed, though Kennedy's 100km sinistral strike-slip hypothesis for the Great Glen Fault in Paleozoic Scotland was common knowledge. Moreover, the hypothesis of continental drift favoured large relative displacements as between Svalbard and Greenland (e.g. Harland 1959). Indeed, a mobilist series of maps was proposed for the Atlantic sector of the Arctic including a thousand km Devonian strike-slip motion of Svalbard from a position off East Greenland to its uncontroversial position north of North Greenland (Harland 1965 amplified in 1966). Later it seemed that some of this motion had taken place along the Billefjorden Fault Zone (Harland 1969a, 1971). A minimum of 200km was postulated for Late Devonian time (Harland et al. 1974). This minimum (only) was accepted by Birkenmajer (1975) in a near-fixist reconstruction within Svalbard. A second major fault was then postulated in Svalbard to separate three terranes or provinces (Harland 1975; Harland & Wright 1979) and these ideas

363--

i ~,17-;ILURIAN

Bulltinden

~,43--

16.6.2

Billefjorden Fault Zone (BFZ)

The B F Z is a prime example o f a fundamental fault with a long history (Harland et al. 1974; M c C a n n & D a l l m a n n 1996) It is used

LAND

GROUP

~t

Monacobreen ,

Plutons~ .~ ] ~Red Bay Gp ! ~ _~>~ ~ 1 / Sikte~tGp ~ 8 ~ .~~ wc~ "r" E ~(~

~

Plutons

;~ Motalafjella Eidembreen

O

Vestg6tabreen Complex ~ ?subduction A

495--

Valhallfonna

SORKAPP

LAND

Kirtonryggen

GROUP

~ O r,,

L9

? LUCIAKAMMEN GROUP

Tokammane

.J

? 545-SCOTIA

GROUP

,z >

I I

A soo-

z

Dracoisen

9 Wilsonbreen A

B~site~

A

nO

Elbobreen

/~

Q.

o n, n,

W n Z ILl n"

o LL

?KROSSFJORDEN GROUP

o

._1

800 - -

900--

' .7

LU

EIMFJELLET

were consolidated (e.g. Harland 1985, Harland et al. 1992). Some,

however, followed these ideas in Svalbard e.g. Friend & MoodyStuart (1972), Hambrey (1989) and to some extent others e.g. Gee et al. (1992). At the same time there was increasing acceptance of Late Caledonian sinistral strike-slip elsewhere (e.g. Ziegler 1978, 1988). However, many continued to treat the pre-Devonian of Svalbard as one Hecla Hoek province without addressing the problem (e.g Birkenmajer 1975), whereas some specifically challenged the thesis e.g. Lamar, Reed & Douglass (1986), Bjornerud, Decker & Craddock (1991), Manby & Lyberis (1992). So it may be useful once again to re-assess the arguments for the thesis here from a Devonian viewpoint. A model for the tectonic evolution of the Western, Central and Eastern Svalbard terranes is shown in Fig. 16.9 for Precambrian to Devonian time.

EASTERN

BILLEFJORDEN GROUP

The question of sinistral Paleozoic strike-slip faulting, transpression and transtension A controversial hypothesis

CENTRAL

Vliss

RICHARODALEN

1000-

ISBJORNHAMNA

?

~

Laponiahalvoya granites Kapp Hansteen volcanics

HARKERBREEN FINNLANDVEGGEN ATOMFJELLA

2000-

?

1

3000 -

? F~2~1 Fig. 16.9. Cartoon of tectonic evolution and stratigraphic sequences in the Western, Central and Eastern Svalbard terranes for Precambrian to Devonian time, with some age constraints (some approximate numerical ages in boxes).

304

CHAPTER 16

here as a test case for the thesis just proposed. Few other faults have as much of their record documented. It continued to be an important fault zone after its strike-slip component had eased by Carboniferous time (Harland 1979). The onus of 'proof' is on the proponent so the arguments in favour of the thesis are summarized.

(a) Stratigraphic comparisons. (i) with Greenland and Arctic Canada. Magnetic ocean striping makes an acceptable case for Svalbard's progress to its present site from a position, at the end of Cretaceous time, north of North East Greenland. The Cretaceous back to Carboniferous record of Svalbard matches stratigraphically the sequence in the Wandel Sea Basin and in the Sverdrup Basin so well that there is now no serious conflict of opinion as to the whereabouts of Svalbard in Carboniferous time except for Bjornoya. Moreover, such a comparison does not fit Svalbard in relation to East Greenland during that interval. Triassic Svalbard facies closely match Sverdrup Basin facies and contrast markedly wth East Greenland Triassic. This supported du Toit's rather than Wegener's 'pre-drift' positioning of the two terranes (Harland 1965, figs 1 and 2). Moreover, the affinity of west Spitsbergen terranes with Pearya in northern Ellesmere Island appears to clinch that relationship back to Proterozoic time. On the other hand the pre-Carboniferous to late Proterozoic record matches Svalbard east of the BFZ with East Greenland remarkably well (e.g. Kulling 1934; Harland 1959, 1965, 1969; Friend et al. 1973; Harland & Wright 1979; Swett 1981; Hambrey 1982; Swett & Knoll 1989; Harland, Hambrey & Waddams 1992, 1993; Fairchild & Hambrey 1995). This was convincing evidence that Ny Friesland must have occupied a site very near East Greenland and far from North Greenland where there is little in common between the two sequences. In 1964 this was the reason for moving all Svalbard north from off East Greenland to the uncontroversial position off North Greenland in Late Devonian time. That was before enough was known of the geology of the preCarboniferous rocks of central and western Svalbard to depart from the fixist view within Svalbard (1965). (ii) Within Svalbard. Having worked on the west coast rocks of Spitsbergen from 1965 it became clear to the author that whereas they could be correlated by palaeontological and glacial evidence with Ny Friesland, their facies were in almost all respects different. Thus, western Spitsbergen could not have occupied its present position separating Ny Friesland from East Greenland. It must have been elsewhere and because older rocks of western Spitsbergen had more similarity with those of North Greenland it lay further north. Thus, it seemed that much of the displacement between Ny Friesland and Greenland must have taken place by strike-slip along the Billefjorden Fault Zone (Harland 1969, 1991; Harland et al. 1974). Further comparisons within Svalbard (e.g. Harland 1972 led to the postulate of a further fault separating western Spitsbergen from central Spitsbergen for the same kind of reasoning (Harland 1975; Harland & Wright 1979, Harland 1985). Further studies (e.g. Harland, Hambrey & Waddams 1993) substantiated this hypothesis. The stratigraphic data for comparison are distributed in Part 2 of this volume (and indicated in Fig. 16.9). For example the close affinity now generally recognised between west Spitsbergen and Pearya, referred to above.

(b) Sedimentological argument. Harland et al. (1974, p. 53) stated that there is no evidence preserved in the Devonian sequence for fault controlled sedimentation along the BFZ. They argued, however, that because there was little indication of easterly derived sediment from an uplifted Caledonian metamorphic complex adjacent to the basin that it must have been elsewhere, either laterally or much deeper. In the light of some recent sedimentary models the lack of easterly derived sediment is not in itself conclusive: transport could have been parallel to the BFZ, but some transport from the east, of sediments of Hecla Hock composition would be expected near the fault zone.

The evidence adduced by Friend & Moody-Stuart (1972) is that the river system supplying the Wood Bay deposits was conspicuously from the highlands in the west and flowing eastwards into the basin. From the south large rivers flowed northward towards a sea somewhere north of Andr6e Land, but there is no sign of a symmetrical eastern margin to the basin. The observation of Reed et al. (1987) that some Devonian units thin eastwards toward the BFZ might suggest that the Ny Friesland block was there. But if it were, there is no evidence of it in current direction or sedimentary composition. Indeed, were there no lateral displacement on the BFZ, Ny Friesland must have been at a far lower level to account for the lack of high-grade metamorphic minerals in the Devonian sediments. The timing is critical. The main tectogenesis of western Ny Friesland was Silurian and the emplacement of the late tectonic batholiths was Silurian through Early Devonian (Chapter 15). Perhaps 15-20km of the orogen needed to be removed before middle Devonian time with local deposition beneath the present Wood Bay Formation. Alternatively on the fixist model the whole of Ny Friesland would have been peneplaned before mid Early Devonian time for the Wood Bay rivers to extend far to the east, at a time when the Ny Friesland batholiths were still cooling. A subsequent uplift (?5000 m) would allow for the present relative height of Ny Friesland (1700 m), and supply of lower grade metamorphics and a relative peneplane. The hypothesis of strike-slip displacement would entail the present Ny Friesland terrane being at least 200 km further south in Early Devonian time, so that the Wood Bay Formation would form a much wider apron extending from the east. Late Devonian strikeslip would bring it along-side the western part of the apron so forming a half graben. The case for not less than 200 km strike-slip may not be widely accepted though a counter argument has not been seen. To avoid the Devonian lateral displacement would require that Ny Friesland and Nordaustlandet would have been situated at depth approximately where they are now. The Silurian-Early Devonian late tectonic batholith would have been submerged beneath the more extensive Wood Bay Formation (later Early Devonian) without generating any positive relief to deflect the stream pattern. Then in Late Devonian time the whole of Ny Friesland (and presumably at least western Nordaustlandet) would have been raised to their present level as a result (presumably) of Svalbardian compression. If this were mechanically possible it would avoid another alternative of Ny Friesland mountains being there all the time, but not shedding any debris into the Devonian deposits. These alternatives leave out of the account the Cambridgebreen (chlorite) Shear Zone formed at shallow depth along the Billefjorden Fault Zone which would on the above fixist model have formed long after the main mid-Silurian transpression with structures metamorphosed under a thick overburden and before the Early Devonian Wood Bay Formation. A further sedimentological postulate due to Friend & MoodyStuart (1972), concerns the Marietoppen Formation in southern Spitsbergen which is correlated with the Wood Bay and the upper part with the Grey Hock of north Spitsbergen. Marietoppen sediments are finer, more carbonate-rich and both sedimentary and biostratigraphic indications are of closer proximity to a marine coastline. Their present position is in the path of the large northward flowing rivers supplying Wood Bay sediments, and indeed nearer to their source. It is difficult to explain such a situation without, as Friend & Moody-Stuart suggested, postulating that the original position was to the northwest of Andr~e Land. On this basis their present relationship would have been accomplished by Mid- and Late Devonian sinistral strike-slip.

(c) Structural arguments. (i) Whereas it is generally agreed that the systems of NNW-SSE faults follow the tectonic grain of the basement and are so controlled, the basement structures are generally less straight than the faults.

DEVONIAN HISTORY It is easy to envisage straight traces of strike-slip faults, generally with steep dip. It is not so easy to account for compressional or extensional faulting in straight lines. If they are the first fractures dip-slip faults are generally arcuate in trace. Dip-slip faults with straight traces may be explained as rejuvenated fundamental faults, generated in the first instance by strike-slip. Given initial fracture in a strike-slip regime, departures from a plane will tend to be shaved off and evened out with strikeslip displacement. Larger departures from a straight trace will result in transpression and transtension. (ii) In the zone of deformation to the west of the BFZ there is evidence of westward overthrusting compatible with normal compression (e.g. McWhae 1953; Lamar, Reed & Douglass 1986). At the same time the cleavages and minor fold axes further north in Andr6e Land trend obliquely to the NNW-SSE BFZ lineament. Such oblique or en 6chelon relationships are compatible with a Devonian transpressive phase. (iii) Throughout the high-grade metamorphic terrane between the BFZ and the Veteranen Line the rocks show pronounced N-S horizontal mineral lineation and ubiquitous boudinage with a N-S extension. This might at first appear as the result of compression. However, from the sinistral rotation and isoclinal folding as well as from mylonite zones this belt has been interpreted as a wide zone of sinistral shear with narrower zones of intense shear near the BFZ and VSZ. These fabrics and structures are related to the main (Silurian) tectogenesis (Chapter 15). (iv) The principal fracture in the BFZ is the Balliolbreen Fault, immediately to the east of which is the Cambridgebreen Shear Zone where amphibolites have been retrogressed to chlorite schists. This is interpreted as a strike-slip shear-fault zone of Devonian age, when most of the overburden evident in the deep structures to the east had been removed. (v) Lack of evidence for compressive deformation coupled with normal faulting throughout middle Devonian time suggests either extensional, transtensional or transcurrent (strike-slip) regimes. (vi) Strike-slip with phases of transtension and transpression, as well as simple transcurrence, is a reasonable plate tectonic model for plates converging first normally, then obliquely and then largely transcurrently. The final docking in Late Devonian time could be transpressional and then compressional. (vii) Lamar, Reed & Douglass (1986) argued from the lack of obvious oblique structures, such as are familiar in the San Andreas dextral transpressive zone, that no strike-slip took place. This seemed obvious from the compressive structures in Wood Bay strata west of the BFZ. In other words a flxist view for Devonian time was maintained. This is just what McWhae (1953) and Harland (1959) concluded from similar evidence. Wider considerations as above then prevailed. In any case partitioning in a transpressive regime between compressional and transcurrent motion is familiar (Harland 1971) and there is evidence of both whether or not they were exactly coeval. To deny something because it has not been observed is weak logic; stronger logic would require conflicting evidence which has not been forthcoming. (viii) A tectonic mechanism to raise the whole of Ny Friesland and at least western Nordaustlandet from beneath a Devonian apron to its present height has not been proposed. Compressive stresses related to Svalbardian movements might not be adequate for such a large terrane. (ix) Seismic data further south suggest that at least 10km of Early and Mid-Devonian strata would be removed by uplift plus a further 2 km to the present height. Mechanically strike-slip could achieve these results more efficiently.

(d) Palaeomagnetic and palinspastic arguments. Many attempts have been made to establish palaeopositions for Svalbard and relative motions between Svalbard and adjoining plates (Storetvedt 1972; Halvorsen 1975; Lovlie et al. 1984; Vincenz et al. 1981, 1984; Watts 1985; Vincenz & Jelenska 1985; Torsvik, Lovlie & Sturt 1985; Jelenska & Lewandowski 1986; Jelenska 1987; Pogarskaya & Goltevitch 1988; Kramov & Ustritsky 1990; Nakazawa et al. 1990).

305

Without detailed discussion it has to be said that data are not adequate to argue Devonian movements or otherwise. Torsvik et al. concluded that Devonian rocks of the Andr6e Land Basin had not moved significantly with respect to equivalent British rocks. This uncertainty to some extent confirms an early conclusion from palaeomagnetic studies of Greenland and Svalbard in 1957 and 1958 respectively, (Bidgood & Harland 1961). The work may have been defeated partly by attempting to distinguish between palaeolongitudes.

16.6.3

Postulated Kongsfjorden-Hansbreen Fault Zone (KHFZ)

The KHFZ case has already been argued in principle as a strike-slip boundary between the Central and the Western terranes. It remains to add some particulars. (a) First depicted as the Central West Spitsbergen Fault Zone (CWSFZ, Harland & Wright 1979) it followed a somewhat arcuate trace from Kongsfjorden to Torellbreen. However, further work on the Vendian correlation in south Spitsbergen led to the inclusion within the western province of the terrane north west of Hansbreen (Harland, Hambrey & Waddams 1993). Further work (since submission of that paper) moved the conjectured locus of the KHFZ back along Recherchebreen, where it was initially placed. There may well be splays through Torellbreen. (b) Where its locus is most closely constrained in Hansbreen, sinistral shear structures are seen to its west at the glacier mouth. Most of the supposed trace of the fault is observed not only, as is typical of major faults, by glaciers or fjords but also by the cover of the younger rocks and younger thrust structures. Indeed, it was suggested that this was a fundamental fault and so a major constraint locating the thrust front of the West Spitsbergen Orogen (Harland & Wright 1979). (c) Its present postulated course is more or less straight (NNWSSE) except where it curves round just north of Broggerhalvoya in Kongsfjorden. This suggests that the northern part of the KHFZ may itself have been bent during in the West Spitsbergen Orogeny and possibly also obliquely offset dextrally in Torellbreen at the same time.

16.6.4

Fault zones in northwest Spitsbergen

Earlier in this chapter the sedimentation of the Siktefjellet and Red Bay Groups led to the conclusion that the varied facies, thicknesses and structures in high energy environments were the result of scarp erosion in a strike-slip environment with both local transpression and transtension. Sinistral shear structures had been noted (e.g. Gee 1972; Harland 1985) and further investigation led to the conclusion that the Siktefjellet-Red Bay terrane lay between the Raudfjorden and Breibogen strike-slip that perhaps ceased to be active before mid-Early Devonian time. The Raudfjorden zone is straight except for minor (?Paleogene) sinistral offsets, although it is rarely exposed, its locus being occupied mainly by ice or water. The Breibogen Fault Zone is better exposed and reveals a substantial straight shear zone with mylonite traces to the west of the more obvious normal dip-slip fault slightly active in Wood Bay time. An oblique s p l a y - the Hannabreen Fault lies between with some evidence also of shear.

16.6.5

Other Fault Zones within Svalbard

Many minor faults or shear zones with a similar trend can be mapped or inferred and may have had a strike-slip component at some Paleozoic time. Such are the Forlandsundet postulated fault, the postulated Marietoppen Fault, the Veteranen shear zone, and the Lomfjorden Fault. These will not be discussed further here.

306

CHAPTER 16

It is arguable that another major fault zone with similar characteristics to the BFZ and the K H F Z may divide Nordaustlandet into east and west, and may also account for facies quite different in the deep stratigraphic wells in Edgeoya.

16.6.6

Ellesmere Island and North Greenland

It is generally agreed that Spitsbergen occupied a position north of North Greenland and from Carboniferous through Early Cretaceous time had affinities with the Canadian Arctic Islands. It is suggested here that the components of Spitsbergen docked in this relationship in Late Devonian time. The Innuitian Orogen extended from the Queen Elizabeth Islands into the North Greenland Fold Belt (Fig. 16.10). However the time constraints from North Greenland are too wide to be helpful here (between middle Wenlock and Late Carboniferous) and so could be referred to the Ellesmerian Orogeny (Late Devonian through Early Carboniferous (Soper & Higgins 1990, 1991).

Trettin (1991) surveyed this whole field and in summary noted: (1) (2) (3) (4) (5)

Late Silurian deformation with asymmetric faulting and folding plus some strike-slip faulting; Lochkovian faulting and folding, in the Boothia uplift; Emsian granite plutonism in Pearya (northernmost Ellesmere Island); Frasnian thrusting, folding, normal faulting and probable strike-slip; Tournaisian (poorly constrained ages) general thin-skinned thrusting and folding in the Parry Islands, Central Ellesmere and Central Hagen fold belts and some deformation generally.

Trettin's analysis of Pearya (1987) suggested a composite terrane with Caledonian affinities. From a Svalbard viewpoint the affinities are close to those of the Western Province in which Ordovician rather Silurian tectonism predominated. Sinistral-strike slip was noted and there need be little conflict in assuming that Western Spitsbergen had already arrived at its Late Devonian location from no great distance. The Central and Eastern provinces of Svalbard finally arrived in Late Devonian time, also by sinistral strike-slip, and were associated with, and possibly part responsible for, the Ellesmerian Orogeny. The timing and sense of movement could fit such a model. At the same time on this model, the Svalbard corner, of what (by Caledonian consolidation across Iapetus) had become the Baltic plate ploughed north and northeastwards over the Thalassic Ocean floor with a possible southward dipping subduction zone, so rucking up a tranverse mountain range that became the sialic core of the Lomosov Ridge (e.g. Harland 1966, fig. 3; section 16.8).

16.6.7

Some geotectonic conclusions

(i) For this author the above hypothesis, first outlined in 1965 and tested ever since, appears to satisfy most available criteria. It is therefore adopted here, though in the knowledge that it is not widely accepted. Figure 16.11, which is explained in the caption, has been constructed in order to expose the hypothesis in its most vulnerable form. There is infinite scope for revision and restatement. It is interesting to consider a common reluctance to accept significant strike-slip components in analysing structures. Past preoccupation with two-dimensional cross-sections may be in part responsible. Certainly the greater the transcurrence along a fault zone the less likely it is that resulting structures will, even if exposed, be matched. To match features, which is easy for small displacements, may need a tectono-stratigraphic approach for comparison of distant terranes with independent subsequent histories. In such circumstances structural studies give little help. In general, the kinematic consequences of plate tectonics require large strike-slip components with transpression and transtension, either of which may be partitioned (Harland 1971). H~kensson & Pedersen (1982) postulated that in eastern North Greenland, along the Harder Fjord Fault Zone, there was a large scale Mid-Late Devonian sinistral (?c. 700km) displacement. Dextral Late Permian strike-slip of c. 200km was interpreted along the same fault zone and a further sinistral Early Jurassic component. Other mid-Paleozoic sinistral displacements have been identified further south in the Caledonides.

16.7 16.7.1

Sequence of events through Devonian time Latest Silurian-Early Devonian events (i.e. pre-Lochkovian)

They are the aftermath of Ordovician-Silurian tectogenesis (main Caledonian events).

Fig. 16.10. Geological provinces of the eastern part of the Canadian Arctic Archipelago and northern Greenland (reproduced with permission from Trettin 1991, fig. 4.3, p. 63).

(a) Ny Friesland Orogeny. Structurally the Ny Friesland Orogeny can be dated between Llanvirn (mid-Ordovician) and Tournaisian

DEVONIAN HISTORY

307

FAULT AND SHEAR ZONES

Stratigraphic interval OWFZ FSZ KHFZ'?MTF My/

Cenozoic

65

Mesozoic to

-540

0

0

?

0

?

0

0

0

0

0

0

0

0

0

20

?

10

50 175

23

30

?

ESZ

strike-slip strike-slip component rate mm yr'

0

-550

0

0

8.5

20

15

75TC20 0

TP-TC 3

TP-TC 5 22 TP

TP-TC 50 5 TC40

3

3

TP-TC 35

7

1

10

9.

10

?

25 TC 1[

5

Ludlow

4

0

0

?

Wenlock

5

? ?

0

0

0

0

0

Llandovery

15

?

0

0

0

0

0

Ashgill

6

0

0

Caradoc

10

CP

CP

0

0

CP

CP

0

0

0

0

0

0

10 25

Cambrian

40

0 0 90

0

0

0

10

0

475

0

18 260

1

2

0

192

0

?0 CP

0

?0 CP

55

130

125

5

0

0

0

5

0

ET OPENING OF IAPETUS

0

0

50

75

450

(early Carboniferous) time. The main Ny Friesland tectonothermal (transpressive) event, long assumed to be Silurian, has been more precisely dated as mid-Silurian with uplift and cooling as late Silurian to Early Devonian on the current time scale adopted here. The two granite plutons in eastern Ny Friesland (Chydeniusbreen Batholith and Nordenski61dbreen Batholith) were emplaced towards the end of the intense folding and on or after partial consolidation, the Chydeniusbreen granite was squeezed so as to attenuate the strata on the west side probably in a transpressive regime. The K-Ar ages were amongst the earliest obtained and indicated Late Silurian to Devonian cooling. Rb-Sr later work suggested a mid Silurian age. It was a composite intrusion. In conclusion cooling, and accompanying unroofing probably persisted into Devonian time.

(b) Smeerenburgian Orogeny. Also probably Caledonian, this different name is applied to the post-Generalfjella Group metasediments because structurally the Early Smeerenburgian tectogenesis is distinguished by both tectonism and magmatism. The Late Smeerenburgian granites are not seen to be covered by later strata. Isotopic ages have indicated Late Silurian to earliest Devonian tectono-thermal events. Two independent values for the age of the Hornemantoppen late tectonic batholith were Late Silurian 413 and 414 Ma. In the Biskayerfonna terrane, Peucat et al. (1989) and Dallmeyer, Peucat & Ohta (1990), while focusing attention on the older rocks, gave two analyses of the Montblanc Formation as 442 and 402 Ma (Llandovery to Pragian). The later Smeerenburgian events are relevant to Devonian sedimentation in the following three ways. (i) North of Kongsfjorden, the Red Bay-type conglomerates (?coeval with Rivieratoppen Formation) rest unconformably on deformed Krossfjorden Group metasediments. In addition the eroded surface of the Generalfjella marbles of Blomstrandhalveya is reddened and fissured, so identifying an exhumed Red Bay unconformity, the sediments only being preserved in small graben and fissures.

250

350

30

0

50

330

0

65 1250

5

36

0 0

105 100

13

112

75 TP 70

147

177 51

?

30

44

330 0 80

Pridoli

Canadian

570

TC

30

0T 0 10 C50

10

30

0

125

10

Llanvirn

0

370

TC-TP 200

0

120

12

0

0

Lochkovian 5

SINISTRAL

?

?300 0

TC

Emsian

TOTAL

WNF

250

0

TC

Givetian

Fig. 16.11. Summary of conjectured strike-slip displacement along the major fault and shear zones of Svalbard to illustrate just one of many solutions to the problem of the total amount and distribution of sinistral displacement. There are unlimited variations from an extreme fixist position with zero digits throughout. It is presented not as a solution, but as a challenge to suggest a better alternative.

BFZ

10 100

Famennian 3

Pragian

BBF

-10

Early

Eifelian

HBF

Approximate combined

0

Late 30C Famennian

Frasnian

RFF

Combined

70

12

65

(ii) Red Bay conglomerates in Liefdefjorden are rich in clasts matching underlying marbles and psammites and other metasediments. However, no granite clasts were recorded (Holtedahl 1914, 1926; Harland 1960) and this suggests that either the Hornemantoppen Batholith was not then unroofed, or that it was then further to the south, or both. (iii) The Lernereyane Formation (Liefdefjorden Group of G e e - in Harland 1985) correlates well with the Generalfjella Formation on the other side of the Raudfjorden Fault Zone and this uppermost unit of the basement rocks is unconformably covered by Rivieratoppen (Red Bay) conglomerates. It could thus seem that through Siktefjellet and early Red Bay group times there was active erosion of the Caledonian basement and that the local highlands had been subdued by mid Red Bay Group time.

16.7.2 Haakonian faulting and sedimentation Gee's (1992) name for a tectonic event to mark the unconformity between the Siktefjellet and Red Bay Groups (and there is an unconformity above the folded Siktefjellet Group strata) is extended for the continuing tectonism through both Siktefjellet and Early Red Bay times i.e. including the deposition of Rivieratoppen and Andr6ebreen Formations, and especially to include the westward thrusting of Andr6ebreen sandstones west of the Hannabreen Fault south of Liefdefjorden (Gee & Moody-Stuart 1966; Piepjohn & Thiedig 1992). It has been argued (Friend et al. 1997) that throughout this time span of unknown age (?Late Silurian to Early Lochkovian) strikeslip faulting was active, controlling sedimentary basins as well as providing sediment sources in the form of local fault scarps. Some deformation was the product of transpression; deepening basins the result of transtension (pull-apart). Although Gee timed the Haakonian event as post-Siktefjellet and pre-Red Bay he had already noted that the faults (RFF, HBF, BBF) suggested sinistral strike-slip at the same time (and in the same community) that Harland et al. (1974) were postulating a long strike-slip history for

308

CHAPTER 16

the Billefjorden Fault Zone. But in that zone there could be no knowledge of Lochkovian events. At this point it might be noted that tectogenesis in the southern Urals has been dated as Early Lochkovian (Korinevskiy 1988) so that the eastern margin of Baltica was then also active.

16.7.3

Loehkovian (Red Bay Group) sedimentation

Extensive denudation of the relief generated by the Haakonian movements continued. The early Red Bay conglomerates suggest continued high gradient alluvial fans developing from fault scarps. The unconformity surface (where marble) is highly fissured and is broken into large blocks partly in situ or autochthonous deposition. However, the conglomerates are generally of uniform composition within each member regardless of the local composition of the basement on which they rest. Conglomerate clast composition (e.g. Harland 1960) matches well available rock types in the basement: the Generalfjella/Wullfberget/Pteraspistoppen type marbles, quartz-mica-schists and quartzose schists similar to the Signehamna/Biskayerfonna pelites and psammites and associated vein quartz. Pink and green quartzites were not matched locally nor were amphibolites. Feldspathic pebbles were noted in the Konglomeratodden Member, but not in the overlying Wulftberget Member. However, feldspars in the sand and silt fractions are conspicuous (both K-feldspars and plagioclase) in the Siktefjellet sandstones, but much less so in later sandstones except near the Raudfjorden Fault at the head of Liefdefjorden (Gjelsvik & Ilyes 1991). Palaeocurrent data from high up the succession indicate a northward axial flow direction in the centre of the Raudfjorden basin with lateral transport systems entering from east and west. The data fit a tilt block - (half) graben model. Andr6ebreen sandstones reflect a typical fluvial sequence with sandy braided river deposits. The succeeding Fr~enkelryggen Formation suggests a fluvial deltaic environment and the Ben Navis Formation, with upwardfining cycles and possible marine fossils (Goujet & Blieck 1977 and Blieck & Heintz 1983) suggests a possibly marginal marine-deltaic environment, with a higher proportion of channel to overbank/ lacustrine deposits than the Fr~enkelryggen Formation. A general denudation in the north is indicated through Red Bay Group time culminating in the marginal marine Ben Nevis Formation.

16.7.4

Postulated Late Lochkovian to Early Pragian movements

There is some evidence of disturbance after, or late in Red Bay Group time (Gee 1972). From observations in 1990, Harland thought that the zone of crushed coarse sandstone in the BBF on Fotkollen, north of Albertbreen, was probably comminuted Red Bay Group sandstone formed in a strike-slip zone, prior to deposition of the local Wood Bay Formation sediments. The change from marginal marine Ben Nevis Formation to continental Wood Bay Formation suggested renewed uplift at this time. This is consistent with the lack of Wood Bay sediments on the Haakon VII Land Block. A compressive (?transpressive) element is therefore possible and so a tentative hypothesis was retained of a 'postulated Late Haakonian phase'. Indeed the basal Wood Bay unconformity of McCann (1996) is consistent with the above, later named the Monacobreen Phase (McCann pers. comm.)

16.7.5

Pragian to Emsian, i.e. mid- to late Early Devonian

(a) Wood Bay Formation sedimentation. This pidce de resistance of Devonian strata has been more intensely researched than any other. Sedimentological studies were notably by Bates &

Schwarzacher (1958), Friend (1961, 1965, 1967) and Friend & Moody-Stuart (1970, 1972) and with particular investigations by Lovlie et al. (1984) (detrital magnetization carried by hematite), Reed (1991) (genesis of calcretes) and Lamar & Douglass (1995). As the most extensive formation of the Liefde Bay Supergroup the Wood Bay sediments provide the best palaeogeologic picture of Devonian time. Of these, the later (Emsian) strata extend further westward. The general setting is an intermontane continental to coastal environment with an apron of streams comprising at least three river systems. The eastern stream was braided, flowed north and northwest, and was heavily loaded with sand-grade sediments rich in feldspar. Larger clasts (1-2 cm exotic pebbles) are infrequent and rarely amount to a conglomerate. The western streams were small, meandering, and eastward flowing, with a sediment load that was poor in feldspar. Conglomerates occur in this situation immediately to the east of the Breibogen fault (BBF) (e.g. on the eastern flanks of Siktefjellet). Bates & Schwarzacher (1958) described a grey green conglomerate containing limestone (Lerneroyone marble clasts) from the eastern shore of Ekmanfjorden. The central river system flowed north but was otherwise similar to the western system. The facies distribution as a whole suggests a tilt block, half graben configuration, with no hint of high land or a source of sediment on the eastern side. High sinuousity streams flowed towards the basin axis from the west and southwest, where a braided axial system flowed northnorthwest immediately to the west of the Billefjorden Fault Zone.

(b) Marietoppen Formation sedimentation. This formation in southern Spitsbergen is coeval with the middle and upper Wood Bay Formation (Murashov 1976, 1996). Friend & Moody-Stuart (1972), drew attention to its high limestone content and apparent distance from a likely source. An upward change from red to grey and black sediments, together with the appearance of molluscs indicates an increasingly anoxic and marginal marine environment. They suggested that such an environment would be expected to the north and west of the present Andr~e Land Group outcrop.

(c) Wood Bay Formation tectonic events. We have little evidence for contemporaneous deformation. There is no positive evidence for contemporaneous strike-slip on the RFF, HBF or BBF, though minor extensional dip-slip normal faulting continued. Lack of evidence for contemporaneous deformation along the BFZ does not preclude fault motion. Palaeocurrent data in the Wood Bay Fm may suggest that the BFZ was an active control on sedimentation. It is possible (as in places along the San Andreas Fault system) for known strike-slip to have little visible effect in fine sediments at the surface (e.g. east of Palm Springs). A transtensional regime is suggested during Pragian-Emsian time to account for: (i)

continental subsidence of the main Andr6e Land basin controlled by movement along the BFZ; (ii) apparent minor dip-slip movement on the BBF; (iii) the further development of the small, elongate basin in Kongsfjorden.

16.7.6 Eifelian-Givetian (mid-Devonian) (a) Mimer Valley Formation sedimentation. Conglomerates indicate tectonic instability, especially in the easternmost rocks (within a few km of the BFZ). Unconformities have been suggested but not established (Murashov & Mokin 1979). Eastern facies represent freshwater, fluvial and lacustrine environments, with a palaeoslope probably tilting towards the east and north, where a molluscan fauna indicates brackish conditions and a transition to the intertidal environments of the Grey Hoek and Wijde Bay facies.

DEVONIAN HISTORY (b) Grey Hoek Formation sedimentation. Grey Hoek brackish and molluscan fauna is evidence of marine-intertidal deposition (Friend 1961). However, Worsley (1972) interpreted the interbedded sandstones and shales as overbank deposits immediately and adjacent to river channels in a flood-plain environment. He suggested a broad coastal swamp environment with occasional desiccation. Marine environments are inferred to the north, but there is no evidence of typical marine salinities. River flow was predominantly to the north and northeast.

The postulated KHFZ was probably mostly covered by Paleogene thrusts. With exceptions at Kongsfjorden and Hornsund - evidence there is circumstantial. The Svalbardian tectonism completed the Caledonian disturbances and separates the Basement as defined here from the latest Devonian through Paleogene cover. At the same time Svalbard became a single (composite) terrane.

16.7.9 (c) Wijde Bay Formation sedimentation. The combination of marine molluscan and non-marine faunas in a silt, shale and sandstone sequence suggests coastal intertidal, partly brackish water deposition. The trend towards a greater proportion of sandstone upward may reflect the build-out of a sediment body into the sea (Friend 1961). Cross-stratification indicates currents flowing to the NNE.

16.7.7

Mimer Valley Phase (early Svalbardian)

Subsidence continued although renewed mobility, uplift and minor compression are suggested by (i) sandstone facies along the BFZ; (ii) conglomerates near the top of the Mimer Valley Formation, i.e. around the mid-Late Devonian boundary. There may, however, be some doubt about the age of the Mimerdalen Formation in relation to the Wood Bay Formation (Piepjohn in Research in Svalbard 1996, Norsk Polarinstitutt).

16.7.8

309

Late Famennian events

(a) Roedvika sedimentation. The Bjornoya coal measures were described systematically by Horn & Orvin (1928). Of three members (Worsley & Edwards 1971: Tunheim Member, 80m Kapp Levin Member, 80m Vesalstranda Member, 200 m), the Vesalstranda and Lower Kapp Levin Member are Late Famennian and the upper part Tournaisian. This is based on floral (Schweitzer 1969), microfloral (Kaiser 1971) and faunal evidence (Holtedahl 1920) with species of Holoptychius a Late Devonian genus. This dating sets a later limit to the Svalbardian movements as there is no discontinuity in the formation; but only if it be assumed that the Svalbardian diastrophism would have extended to Bjornoya. So this is somewhat inconclusive. However, a similar late Famennian deposit in Spitsbergen appears also to begin the Billefjorden Group coal measures (van Veen pers. comm.). On sedimentological evidence, Worsley & Edwards (1976) Gjelberg (1978, 1981) and Friend (1969, 1978, 1981) all concluded that lacustrine, deltaic and fluviatile environments prevailed during Late Devonian time with an early Carboniferous transition to marine conditions, but there is no marine indication in the Roedvika Formation. Cross-bedding indications are diverse with a general palaeoslope to the north. A moist climate is inferred.

Frasnian-Famennian (Late Devonian) events

Late Mimer Valley members may well be of Frasnian age and the Roedvika Formation of Bjornoya is part Famennian and part Hastarian (earliest Carboniferous). Exact ages are uncertain but there is a gap - at least Late Frasnian to Early Famennian with no depositional record.

Svalbardian diastrophism. It has been mentioned (Chapter 8.6) that all the Old Red Sandstone formations (of the Liefde Bay Supergroup) have been deformed and that relatively undeformed latest Famennian and Tournaisian strata overstep the truncated structures. This relationship was earlier recognized by Vogt (1928) who named the phase 'Svalbardian folding' (1936). So much is established. The question of sinistral strike-slip and transpression has been discussed at length in Section 16.6 and it is concluded here that the disturbances were heralded by the Mimer Valley phase. The transpression/transtension hypothesis is not claimed as a purely Devonian phenomenon, but the Svalbardian movements are claimed to be final stages in a long history of strike-slip faults on the BFZ and probably on others. The configuration of the BFZ, coupled with a diminution of strike-slip stresses after Wood Bay transtension or transcurrence, turned to partitioned transpression and then finally to compression as the terranes locked across the fault, which then became the locus of dip-slip displacements. Away from the Billefjorden Fault Zone other fault movements cannot be so well dated. The RFF, HBF and BBF cannot be so related partly because of a lack of Carboniferous cover. However, they were certainly not so active since Early Devonian time. When asymmetrical the structures verge westwards rather than eastwards.

(b) Pre-late Famennian denudation in Spitsbergen. The Triungen Member of the Horbyebreen Formation has been claimed to be late Famennian from palynomorph data (van Veen pers. comm.). The Svabardian movements must have resulted in uplift and erosion; certainly by the time of deposition of Tournaisian strata of the Billefjorden Group relief was substantially reduced. An early study by Hutchins (1962) showed a lack of metamorphic minerals that would be typical of the underlying Ny Friesland Hecla Hoek suggesting that already by that time there was a peneplane with the transport of sediment from a distance.

16.8

A Lomonosov conjecture

Chapter 6 concluded with a possible sequence of events in Nordaustlandet including the northward progression of eastern Svalbard by subduction over the Thalassic ocean floor to the present position of the Lomonosov Ridge. This progression probably began in Silurian time, probably continued in Devonian time and certainly climaxed in Late Devonian (Frasnian-Early Famennian) time. On this conjecture the Devonian thermal events recorded isotopically from Northern Nordaustlandet would be the consequence of deep burial beneath it of the subducted slab. The adjacent orogen would have caused the Tertiary structure. The possibility of such a major Devonian event with the production of the Lomonosov submarine orogen in advance of Nordaustlandet may merit further consideration and testing. On this basis a Lomonosov Orogeny is suggested as possibly coeval with the Ellesmerian tectonics in the Queen Elizabeth Islands.

Chapter 17 Carboniferous-Permian history of Svalbard W. B R I A N H A R L A N D with a c o n t r i b u t i o n by I S O B E L G E D D E S 17.1 17.2 17.3 17..3.1 17.3.2

Early work, 310 Stratigraphie frame Biinsow Land Supergroup, 312 Structural frame, 314

17.4 17.5

Carboniferous and Permian time scale, 316 Carboniferouslpermian sedimentary environments (I.G.), 318

Basins and blocks, 315 Boundary faults, 316

17.5.1 Late Famennian-Tournaisian-Visean-Serpukhovian deposition (Billefjorden Group), 318 17.5.2 Bashkirian-Moscovian-Kasimovian deposition (lower Gipsdalen Group), 320 17.5.3 Kasimovian-Gzelian-Asselian-Sakmarian deposition (middle Gipsdalen Group), 322 17.5.4 Sakmarian-Artinskian deposition (upper Gipsdalen Group), 323 17.5.5 Kungurian-Guadelupian deposition (Tempelfjorden Group), 323 17.6

Carboniferous and Permian fossil record, 324

17.6.1 Plant life, 326

Rocks formed in these two periods do not easily divide at their mutual boundary and it is convenient to treat them together. In doing so we are addressing perhaps the best known and most conspicuous formations of Svalbard. Few geologists have been to the archipelago without noticing fossils and making some observations on these rocks. We are therefore embarking on a substantial study. A three-fold division of Paleozoic rocks in Svalbard is convenient in which Silurian and Devonian or middle Paleozoic history, dominated by Caledonian events, is followed by a Late Paleozoic interval of increasingly stable conditions which show little impact from Variscan, Ellesmerian or Uralian events elsewhere. This contrast applies conspicuously in Permian western Arctic regions. The Carboniferous-Permian outcrops are shown on Fig. 17.1. These rocks are the lower element in the Post-Devonian cover sequence divided between the Spitsbergen Basin and the Eastern Platform and Bjornoya. The outcrops are disposed in two main areas in Spitsbergen and one in Bjornoya. The Spitsbergen Basin was at first divided into troughs by inherited N-S faults. These then coalesced and extended throughout Spitsbergen. The present outcrop pattern resulted (i) from Late Cretaceous tilting with loss by erosion to the north, burial to the south and wide E-W exposure across the middle. (ii) A linear belt along the west coast, brought to the surface by folding and uplift along the Cenozoic West Spitsbergen Orogenic Belt from Kongsfjorden to Hornsund. Outcrops are frequently controlled by overthrusting from the west. (iii) The Bjornoya Carboniferous outcrop is a result of a broad anticline plunging to the north. It has been affected by pre-Permian N-S trending faults. From the early 1960s the Carboniferous-Permian formations have been classified in three groups applicable to the whole of Svalbard. The Billefjorden Group, mainly continental, may overlap into latest Devonian time, but is essentially Early Carboniferous (i.e. Mississippian). It tends to occupy local basins. The Gipsdalen Group, often beginning and ending with evaporites, formed mainly of carbonates. It ranges through Late Carboniferous (Pennsylvanian) and Early Permian (Rotliegendes) time. The Tempelfjorden Group, often of cherty siliciclastics, is the most extensive, uniform in facies, and most easily recognized by its tough nature. Not easy to correlate internationally, it is of early Late Permian (Zechstein) age. The three groups are combined in the Bfinsow Land Supergroup, the land where the first detailed stratigraphy was worked out.

17.6.2 17.6.3 17.6.4 17.6.5 17.6.6 17.6.7 17.7 17.7.1 17.7.2 17.7.3 17.7.4 17.7.5 17.7.6 17.7.7 17.7.8 17.8 17.8.1 17.8.2

Foraminifers, 326 Corals, 327 Brachiopods, 327 Bryozoans, 327 Gastropods, 328 Trilobites, 328 Carboniferous-Permian tectonic control of sedimentation (W.B.H. & I.G.), 328

Tournaisian-Visean-Serpukhovian events, 328 Bashkirian-Moscovian events, 330 Kasimovian-Gzelian events, 331 Asselian-Sakmarian events, 332 Artinskian events, 333 Kungurian-Guadelupian events, 334 Latest Permian events, 334 Carboniferous and Permian sedimentation rates, 334 Carboniferous and Permian palaeogeology, 335

Palaeotectonic relationships, 335 Palaeosedimentary relationships, 335

Economic interest. Early exploration was often motivated by thoughts of economic gain. Coal was the obvious first target being easy to locate in scree or moraine and of immediate practical use for heating even before systematic mining was introduced. Coal is characteristic of, and in the time span of this chapter limited to, the Billefjorden Group. It is mainly of (late Famennian and) Mississipian age. The Roedvika Formation of Bjornoya was mined at Tunheim and the occurrences in Billefjorden, in the Horbyebreen (Hoelbreen Member) and Mumien (Birger Johnsonfjellet Member) formations, are mined at Pyramiden and there were exploratory drillings in northwest Biinsow Land at Brucebyen and in Gipsdalen. These occurrences crop out at the surface; but interest has been shown in the Gipsdalen area of Btinsow Land where significant subsurface coal reserves have been estimated. Gypsum and anhydrite occur in abundance, especially in the lower Gipsdalen Group strata of Billefjorden. Hydrocarbons have been the principal interest since about 1960. For source rocks the bituminous fusuline limestones at the base of the Wordiekammen Formation in Central Spitsbergen and the coeval Kapp Dun6r Formation in Bjornoya are of most interest. As a source of gas, the Billefjorden Group sandstones with a high coal content, might be significant. Reservoir rocks are especially sought amongst the Early Permian carbonates whether in the solution breccias of the Gipshuken Formation or in the (Palaeoaplysinid) reef build-ups in a range of Permian strata including the widespread Kapp Starostin Formation. The overlying Triassic shales provide a relatively impermeable cover, but have often been removed. The underlying Kapp Starostin Formation, with its dense cherty siliciclastics, possibly provide a more reliable and identifiable seal.

17.1

Early work

Parry's Polar expedition collected Late Paleozoic fossils. The first stratigraphic synthesis was made by Nordenski61d (1863, 1866, 1871, 1875). Nathorst 1910 produced a modified scheme shown in Fig. 17.2. About the same time the studies in Bjornoya of Andersson (1900) and Holtedahl (1911) led to a detailed account of Carboniferous strata by Holtedahl (1913). The 1930s saw much detailed work within Nathorst's stratigraphic framework. These included De Geer, Sandford, Odell &

CARBONIFEROUS

/9 ~

/12 ~

-81

~

AND

/15 ~

PERMIAN

HISTORY

/18 ~

OF SVALBARD

121 ~

/24 ~

SVALBARD CARBONIFEROUS & PERMIAN OUTCROPS ~8oo

311

\27 ~

80 ~

5

-_/__

8m

9~

'.,,.

I 9

.i

9. l

I

l

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'" I /.....

791

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..-.'ii : :i ::i!i:::: i

27 ~

I

79 ~

...~--.~

s

cb"-

~ =.I:i: >

|

s-....

is

I~1 ~

~',

-278~ 7 8~

r

~

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+

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.o:.:

+

o

I

Post-Permian

Pre-Carboniferous

" ii ii'~ ~}/"

/

" "cir... "

/12 ~ deep well

6o ~

~ /15 o

/

0 121~

,

km 124 ~

,

lqo 76

Fig. 17.1. Map of Svalbard showing the distribution of Carboniferous and Permian rocks. Carboniferous and Permian are not distinguished on this small scale map, partly because the boundary does not correspond with a convenient mapping boundary. The outcrops are compounded i.a. from the maps in chapters 4, 5, 9, 10 and 11. Dashed lines limit ice cover.

312

CHAPTER 17

Gee et al.

1953 F o r b e s et al. 1 9 5 8 Upper

Nathorst 1910

Hovtinden Mbr

Middle

PRODUCTUSFOHRENDE KIESELGESTEINE

BRACHIOPOD CHERTS

Lower

KAPP STAROSTIN FM

Svenskeega Mbr

D a l l m a n n et a / . 1 9 9 6 adopted here

Z

u_ O

3 members in central Spitsbergen

KAPP STAROSTIN FM

V~ringen Mbr

Limestone A

SPIRIFERENKALK

SKS

Cutbill & C h a l l i n o r 1 9 6 5

I--

UPPER GYPSIFEROUSSERIES Limestone B

gesteine

Brucebyen Beds

Lower

CYATHOPHYLLUMKALK

Black Crag

(.9 CO

~,o

~CO

....... Black Crag

Cadellfjellet Mbr

Passage Beds

Z I.IJ

UNTERER GIPSSTUFE

Tyrrellqellet Mbr

{

Tyrrellfjellet Mbr LL

Mid

_i Pyramiden 1 C~176 I LOWER GYPSIFEROUS SERIES

I

~)

GIPSHUKEN FM

Finlayfjellet Beds

"Limestone B"

Upper WORDIEKAMMEN LIMESTONES

Fusuline

2 members in central Spitsbergen

GIPSHUKEN FM

Pyramiden Beds Minkinf]ellet Mbr

z LU LU n"

~0 n"

q

z

O z iJ.l n, O z

WORDIE- DICKSON LAND KAMMEN SUBGROUP FM

Brucebyen Beds

Cadellf]ellet Mbr tu a Black Crag beds o9 13MINKINFJELLET FM 3 members

i.' Carronelva Beds

CAMPBELLRYGGEN SUBGROUP

EBBADALEN FM 3 members

EBBADALEN FM i

KULM SANDSTEIN

BILLEFJORDEN SANDSTON ES

Hultberget Mbr Sporehogda Mbr Hoelbreen Mbr Triungen Mbr

SVENBREEN FM H~RBYEBREEN FM

HULBERGET FM .B.Birger,Johnson.f]ellet Mbr MUMIEN FM bporenogaa M~r HoelbreenMbr HORBYEBREEN -~CO Triungen Mbr ~ FM ~ 3I

Fig. 17.2. Chart illustrating successive classifications of rock units in Spitsbergen.

Kulling (Nordaustlandet); Stensi6, Hoel & Lyutkevich (central Spitsbergen); Nathorst, Holtedahl, Hoel & Orvin (western Spitsbergen). Freebold (1936, 1937) investigated the rich Permian brachiopod fauna. M u c h of this work was summarized by Orvin (1940). Since 1940, Norwegian, British, Soviet, Polish and German groups have contributed to geological knowledge: There was a resurgence of Norwegian work in the late eighties and nineties; e.g. by Stemmerik & Worsley (1989, 1995). Perhaps most significantly the rationalization of Carboniferous and Permian stratigraphic units was completed by SKS (Dallmann et al. 1996). The Norsk Polarinstitutt had fostered in Norway an interest in these rocks (e.g. Major & Winsnes 1955; Winsnes 1966, 1979; Flood et al. 1966; Lauritzen & Worsley 1975; Worsley & Edwards 1976; Lauritzen 1977, 1981, 1983; Gjelberg 1981, 1987; Gjelberg & Steel 1979, 1981, 1983; Nysaether 1977; Winsnes & Worsley 1981; Skaug et al. 1982; Mork 1987; Johannessen & Steel 1992) including the publication of the series of 1:500 000 geological maps (Flood, Nagy & Winsnes 1971; Hjelle & Lauritzen 1982; Lauritzen & Ohta 1984; Steel &Worsley 1984). British expeditions, in particular the Scottish Spitsbergen Syndicate (SSS) around 1920 and then the Cambridge Spitsbergen Expeditions (CSE), were concerned with the Late Paleozoic strata beginning in 1938 (Harland in McCabe 1939). As a result, a new stratigraphic scheme was proposed (Gee, Harland & McWhae 1953; McWhae 1953; Forbes, Harland & Hughes 1958; Forbes 1960). A series of expeditions from Birmingham in 1948, 1951, 1954 and 1958 added to the knowledge of Late Paleozoic rocks in western Spitsbergen (e.g. Baker, Forbes & Holland 1952; Weiss 1953; Dineley 1958; Bates & Schwarzacher 1958). Playford (1962, 1963) undertook extensive palynological work and Gobbett (1963) monographed the brachiopods. Between 1961 and 1965, Cutbill, Challinor, and later Holliday, worked extensively on Carboniferous and Permian stratigraphy. Cutbill's work enabled a detailed revision of the stratigraphy based on fusulinid zones comparable with those of the Russian Platform (Cutbill & Challinor 1965). These contributions are marked in the stratigraphic schemes shown in Fig. 17.2 including subsequent modifications in the light of Worsley & Edwards (1976) and this work.

Russian geologists have paid attention especially to the Permian sequence (e.g. Livshits 1960; Ustritsky 1962, 1967, 1979, 1980; Burov et al. 1964, 1965; Klobov 1965; Sosipatrova 1967, 1969; Stepanov 1936, 1937, 1957; Pchelina 1977; Sosipatrova 1967a,b, 1969) established foraminiferal zones over the whole carbonate sequence (Gipsdalen and Tempelfjorden Groups) which are, however, not sufficiently widely recognizable throughout Svalbard to be a useful tool for internal correlations. Work on Bjornoya was brought forward by Krasil'shchikov & Livshits (1974). Polish geological expeditions, based in southern Spitsbergen, have resulted in many publications on aspects of stratigraphy, structure and palaeontology (e.g. Biernat & Birkenmajer 1981; Birkenmajer 1959b, 1960a, 1964a, 1979b, c, 1984d; Birkenmajer & Czarnieki 1960; Birkenmajer & Turnau 1962; Czarnieki 1966, 1969; Fedorowski 1964, 1965, 1967, 1975, 1982; Rozycki, 1959; Siedlecka 1968, 1970, 1972 & Siedlecki 1960, 1964, 1970; Siedlecki & Turnau 1964; Malecki 1968, 1973, 1977). From German expeditions to Bjornoya in 1964 and 1967 Schweitzer (1967a, b, 1969) monographed the macroflora and Kaiser (1970, 1971, 1974) recognized several useful microfloral assemblages. French contributions to coal data, include Michelsen & Khorasani (1991).

17.2

Stratigraphic flame: B/insow Land Supergroup

The Bfinsow L a n d Supergroup conveniently combines the three groups of Carboniferous and Permian formations including some latest D e v o n i a n strata. The supergroup thus approximates the C a r b o n i f e r o u s - P e r m i a n chapter in Svalbard history. The position of the initial Carboniferous and Permian boundaries are only approximately k n o w n in the strata, but the supergroup as a whole is readily distinguished by late D e v o n i a n and Late Permian unconformities each with biostratigraphic hiatus.

CARBONIFEROUS AND PERMIAN HISTORY OF SVALBARD

Approximate age

I Trll

Approximate Location Hornsund Bjerneya Serkapp Land

Bellsund

Isfjorden

Nordfjorden

Nordensk61dLd

W.J. Ld

OscarllLd

Billefjorden DicksonLd

313

Tempelfjorden

Hinlopenstretet

B0nsowLd OlavVLd

Nordaustlandet

Griesbachian Lopingian Revtanna Hovtinden Mbr Mbr ...................................................... KAPP STAROSTIN Svenskeegga ............................

Capitanian |

Wordian Ufimian

GROUPS SASSEN-DALEN GROUP

MISERY-FJELLET FM

TOKROSSOYA FM

veringen

Stensi6fjt Mbr

i Selanderneset Mbr i ~-15aia-n~Jer-bu-kta .................... L. . . . . . . . M--br-

FM Mbr Mbr

~ m ~ ~ m ~ ~) ~D (:2

m c: Z

Kungurian

Artinskian

O

HAMBERG -FJELLET FM

GIPSHUKEN Kloten Mbr

Vengeberget

Mbr

FM

O --~

Zeipelodden Mbr

i "o

Sakmarian

Pl I

Asselian Gzelian

2 g

KAPP DUNER FM

Kasimovian

KAPP HANNA FM

Moscovian

KAPP[ 3 KARE IMbrs FMI

Bashkirian

r'-

Z

LANDNORDINGSVIKAFM

Tyrrellfjellet Mbr

TRESKEL-

WORDIEKAMMEN

-ODDEN FM

_

-,~ ~

FM

..................... Merebreen Mbr

Brattberget Mbr

TARNKANTEN FM PETRELLSKARET FM

SCHETELIGFJT FM BROGGERTIN-DEN FM

z 2> t-" m z

~Kapitol Mbr

Cadellfjellet Mbr

co

c

CHARLESBREEN SUBGROUP

HYRNEFJT. FM Helmen Mbr

~ ,~.

~

MINKINFJT. FM 3 Mbrs

BRUNFJT. -RDBR-EEN FM c u~

EBBADALEN FM 3 Mbrs HULTBERGETFM

;u O

c::~l -o ~

c

I

-o m

-o

:;0 Serpukhovian

O Nordhamna Mbr

Visean

NORD-

Kapp -KAPP Harry FM Mbr

Tournaisian C1

ID31 Famennian

ROED- Tunheim Mbr ,-VIKA .K~-p -~ i FM Levln Mbr

SERGEIJEVFJELLET FM HORNSUNDNESET FM ADRIA- Meranfjt. Mbr -BUKTA FM

VEGARDFJELLA FM

ORUSTDALEN

Julhegda Mbr Haitanna Mbr

V~sal"~randaMbr

FM

Birger Joh nsonl~t, r MUMIEN FM Sporehegda Mbr HORBYE- Hoelbreen BREEN Mbr FM

Triungen Mbr

g

c

O o ;;0 O c "o ANDNEELANDGROUPm

Fig. 17.3. Lithostratigraphic scheme for Carboniferous and Permian formations of the Biinsow Land Supergroup. It plots the recommended relationships between the named units and the age estimates are only approximate.

As recently determined latest Devonian strata are exceptional to the Billefjorden Basin (Van Veen pers. comm.), they have long been known in Bjornoya. These share the typical continental grey clastic facies, rich in plant material and often-coal-bearing. This Billefjorden Group developed in separate basins throughout Svalbard. It is mainly of Tournaisian and Visean age. The overlying Gipsdalen Group spans Late Carboniferous (Pennsylvanian) through Early Permian (Rotliegendes) time with possible breaks around Serpukhovian and in Artinskian time. The lower (Campbellryggen) subgroup begins with red clastics and evaporites with an increasing carbonate content upwards. Variable basinal facies reflect a complex but decreasing diastrophism. The upper (Dickson Land) subgroup comprises widespread relatively uniform carbonate facies changing to evaporite and carbonate facies. The Tempelfjorden Group formations overlie the Gipsdalen Group with a recognizable break. The rocks are distinctively resistant typically of siliciclastics and cherts. They are the most easily recognizable strata in Svalbard reflecting a relatively uniform environment of deposition. It was the above lithological characteristics which led to the three-fold grouping of multifarious formations (Cutbill & Challinor 1965) at a time when the American lithostratigraphic code was becoming employed internationally. In an attempt to agree and systematise the developing lithostratigraphic nomenclature the Stratigraphisk Komite for Svalbard (SKS) achieved an early report which is followed here (Dallmann 1996). What follows is thus in conformity with those recommended conventions. The units already encountered in the regional chapters 4 5, 9 10 and 11 are listed below with reference to their definition and set out in Fig. 17.3 which shows their approximate distribution in time and space. It is

not, however, a time-correlation chart, but rather to show the formal relationship of the units and hence the stratigraphic framework of the rocks for discussion. Biinsow Land Supergp (new) Tempelfjorden Gp (Cutbill & Challinor 1965) with three formations: Kapp Starostin Fm (Cutbill & Challinor 1965) extends throughout northern Svalbard and with other names in the south. It is divided threefold into members, some yet to be formalized. Hovtinden Mbr (Cutbill & Challinor 1965) was the original upper division. Selanderneset Mbr (Burov et al. 1965) is the uppermost equivalent in Nordaustlandet. Palanderbukta Mbr (Lauritzen 1981) is below it in Nordaustlandet. Stensi6fjellet Mbr (SKS 1996) is an equivalent in north central Spitsbergen. Revtana Mbr (SKS 1996) is an equivalent in the Bellsund region. This upper division is often characterized by glauconitic sands Svenskeegga Mbr (Cutbill & Challinor 1965) is the middle division, not so distinctive and defined by the overlying and underlying members. The upper and middle divisions correspond to the Productus fOhrende Kieselgesteine of Nathorst (1910). Veringen Mbr (Cutbill & Challinor 1965) is the lower distinctive and widespread division of the formation. It has an extensive submarine development and corresponds to the Spiriferenkalk of Nathorst (1910). Tokrosseya Fm (Siedlecki 1964) is the correlative of the Kapp Starostin Fm in its eponymous island and in Sorkapp Land. Miseryfjellet Fm (Worsley & Edwards 1976) is an approximate equivalent of the lower part of the Kapp Starostin Formation in Bjornoya. Hambergfjellet Fm (Worsley & Edwards 1976) is not yet allocated to any group being intermediate between the overlying and underlying formations. It has a small outcrop on Bjornoya, but is reported to have an extensive submarine development.

314

CHAPTER 17

Gipsdalen Gp (Cutbill & Challinor 1965). In the type area of north central Svalbard the group was originally defined by three formations: Gipsdalen, Nordenski61dbreen, and Ebbadalen with further formations in South Spitsbergen and four formations in Bjorn~ya. However, to facilitate more convenient mapping units the Nordenski61dbreen and Svenbreen formations have been redivided and replaced using earlier names and one later name. Four subgroups have also been introduced to combine all except the Bjornoya formations. Diekson Land Subgp (SKS) is defined by two formations. Gipshuken Fm (Cutbill & Challinor 1965) is characterized by clastics evaporites and breccias with a number of informal members, three in the upper part and three in the lower part. Bredsdorffbergen Mbr (SKS 1996) to the northwest in Spitsbergen Templet Mbr (SKS 1996) to the northeast in Spitsbergen Sorfonna Mbr (SKS 1996) in Nordaustlandet. The three lower members alternate evaporites with, probably related, collapse breccias. Kloten (breccia) Mbr (Cutbill & Challinor 1965) Vengeberget (evaporite) Mbr (SKS 1996) Zeipelodden Mbr (Lauritzen 1981) Wordiekammen Fm (Gee, Harland & McWhae 1953) was reintroduced by SKS for the upper two members of the Nordenski61dbreen Fm as representing relatively uniform widespread carbonate facies especially the upper member. Tyrrellfjellet Mbr (Cutbill & Challinor 1965) extends from NE Spitsbergen to Bellsund in the south. It includes the Finlayfjellet Beds at the top (originally Limestone B) and the Brucebyen (fusuline) Beds near the bottom. Cadellfjellet Mbr (Cutbill & Challinor 1965) in central and NE Spitsbergen with three beds: Mathewbreen, Gerritbreen and Black Crag at the bottom which to the east may approximate the Pyefjellet Beds. Kapitol Mbr (Cutbill & Challinor 1965) occupies the Nordfjorden High. Morebreen Mbr is the equivalent in the northwestern outcrops: In the Nordaustlandet the whole Wordiekammen Fm is represented by the Idunfjellet Mbr. Campbellryggen Snbgp (Forbes, Harland & Hughes 1958) was reintroduced by SKS to comprise three formations in the Billefjorden trough and two formations one in NE Spitsbergen and one in Nordaustlandet. Unlike the Wordiekammen Fm these reflect separate basinal developments. Minkinfjellet Fm (Cutbill & Challinor 1965) is divided into three members. Fortet Mbr (Dallmann 1993) in the north centre Terrierfjellet Mbr (SKS 1996) Carronelva Mbr (Cutbill & Challinor 1965) Ebbadalen Fm (Cutbill & Challinor 1965) is also divided into three members Odellfjellet Mbr(Johannessen & Steel 1992) Trikolorfjellet Mbr(Holliday & Cutbill 1972) Ebbaelva Mbr (Johannessen & Steel 1992) Hultberget Fm (Cutbill & Challinor 1965) is the upper part of their Svenbreen Fm, now divided mainly in account of a mappable boundary between these red beds and what is now renamed below as the Mumien Fm. Malte Brunfjellet Fm (SKS 1996) is an equivalent in northeastern Spitsbergen of the Minkinfjellet Fm. H~irbardbreen Fm (Cutbill & Challinor 1965) is similarly a corresponding unit in NordaUsttandet. Charlesbreen Subgp (Dineley 1958; SKS 1996) is analogous to the Campellryggen Subgp to the west of the Nordfjorden High in the northwestern and western outcrop. It comprises four formations, two in the north at Broggerhalvoya. Seheteligfjellet Fm (Cutbill & Challinor 1965) Holtedahl (1913) described his Moscovian fauna from this unit. Broggertinden Fm (Cutbill & Challinor 1965). Further south are two formations along the west coast more or less equivalent to the two in the north. T~irnkanten Fm (Cutbill & Challinor 1965). Petrellskaret Fm (Cutbill & Challinor 1965). Treskelen Subgp (SKS 1996) was instituted by SKS to combine two formations in inner Hornsund. Treskelodden Fm (Birkenmajer 1959b). Hyrnefjellet Fm (Birkenmajer 1959b). Not combined into a subgroup are the four original units described by Andersson (1900) from Bjornoya. Kapp Dun~r Fm (Krasil'shchikov & Livshits 1974) is the original 'Fusulina Limestone'.

Kapp Hanna Fm (Krasil'shchikov & Livshits 1974) is the original 'Yellow Sandstone'. Kapp Kfire Fm (Worsley & Edwards 1976) is the original 'Ambigua Lst': it has three members. Kobbebukta Mbr (SKS 1996). Efuglvika Mbr (Worsley & Edwards 1976). Bogevika Mbr (Worsley & Edwards 1976). Landnordingsvika Fm (Krasil'shchikov & Livshits 1976) is the original 'Red Conglomerate'. Billefjorden Gp (Forbes, Harland & Hughes 1958) is the original Culm or Kulm of older authors and comprises sandstones formations with black plant remains and coals. It is not divided into subgroups but is represented by three pairs of formations and one threefold succession in each of four or five distinct basins or outcrops. In the Billefjorden trough are the: Mumien Fm (SKS 1996) comprising the Birger Johnsonfjellet Mbr (SKS 1996). Sporehogda Mbr (Cutbill & Challinor 1965). Horbyebreen Fm (Cutbill & Challinor 1965) comprising the Hoelbreen Mbr (Cutbill & Challinor 1965). Triungen Mbr (Cutbill & Challinor 1965). Along the west coast (west of the Nordfjorden High) from Broggerhalvoya to Bellsund are two formations. VegardfjeHa Fm (Dineley 1958). Orustdalen Fm (Cutbill & Challinor 1965). In Inner Hornsund and in Sorkapp Land are three formations. SergeijevfjeHet Fm (Siedlecki 1960). Hornsundneset Fm (Siedlecki 1960). The third and lower formation is restricted to inner Hornsund. Adriabukta Fm (Birkenmajer & Turnau 1962). This has been divided into three members. Meranfjellet Mbr (Dallmann e t al. 1993). Julhogda Mbr (Dallmann et al. 1993) Haitanna Mbr (Dalhnann e t al. 1993). In Bjornoya are two formations: Nordkapp Fm (Cutbill & Challinor 1965) with two members. Nordhamna Mbr (SKS 1966). Kapp Harry Mbr (SKS 1996). Roedvika Fm (Cutbill & Challinor 1965) with three members. Tunheim Mbr (Cutbill & Challinor 1965). Kapp Levin Mbr (Worsley & Edwards 1976). Vesaistranda Mbr (Worsley & Edwards 1976).

17.3

Structural frame

The u n c o n f o r m i t y surface on which the Bfinsow L a n d Supergroup strata rest is a major, perhaps the most significant, structural feature of Svalbard geology. The older (or basement) rocks below are characterized by complex geosynclinal and orogenic histories. The y o u n g e r (or cover) rocks have a coherence that unites t h e m into a basin and platform sequence beginning in latest F a m e n n i a n time. However, the complexity of the basement h a d a lasting effect on the differential deposition, erosion and d e f o r m a t i o n of the y o u n g e r rocks by providing an inherited terrane framework. Events o f later history derive primarily from thickness and facies variations which call for some explanation. The structural n o m e n c l a t u r e adopted here (Fig. 17.4) is intended to serve generally for p o s t - D e v o n i a n history. There is a general N N W - S S E trend o f principal features so that over most of Spitsbergen the terranes a n d b o u n d i n g zones can be identified in E W traverses. The cover rocks m a y be b r o a d l y divided into an Eastern Svalbard Platform and a Spitsbergen Basin. The latter, for C a r b o n i f e r o u s time in particular, m a y be divided into blocks and troughs as s h o w n in Fig. 17.4. Subsequently the distinction between the east a n d central (Spitsbergen) basins is not so m a r k e d and both m a y be s u b s u m e d in the Spitsbergen Basin. Late Paleozoic basins show trends similar to the earlier D e v o n i a n graben, reflecting the c o n t i n u i n g influence of the same m a j o r fault zones u p o n sedimentary patterns. The D e v o n i a n graben was inverted during Late D e v o n i a n time to p r o d u c e the N o r d f j o r d e n High, a positive feature t h r o u g h to mid-Triassic time. Three depositional

CARBONIFEROUS AND PERMIAN HISTORY OF SVALBARD

315

basins are recognized, within which Early Carboniferous rocks have been preserved in structural troughs. The basins are separated and bounded by positive tectonic blocks, defined by major northsouth lineations.

17.3.1

Basins and blocks

The Eastern (Svalbard) Platform. In Nordaustlandet, in the northeast of Svalbard, there is a complex sequence of mainly pre-Devonian rocks on which a condensed succession of later Carboniferous and Permian rocks rest unconformably. Isopachs and facies distribution point to the existence of a region of uplift and sediment source in the east throughout 'Middle' and Late Carboniferous time, which continued into Permian time. The western margin of the block is not clearly defined, but there appears to be a fault or axis of rapid attenuation in the region of Hinlopenstretet.

The East (Spitsbergen) Basin. This basin extends from Ny Friesland southwards, possibly onto the northern Barents Shelf. There are two distinct troughs, preserving Early Carboniferous sediments, separated by a weak axis of Bashkirian and later uplift in Ny Friesland. Later Carboniferous rocks are continuous across the basin, but thin to the east (Fig. 17.4). The Billefjorden Trough lies on the western edge of the basin and preserves the thickest sequence of Carboniferous rocks in Svalbard, over 1500 m. It was a site of decreasing subsidence throughout the Carboniferous Period. The Lomfjorden Trough, the easternmost of these troughs, underwent less subsidence. It has been accentuated by post-Permian uplift in central Ny Friesland.

The Nordfjorden Block. This block, bounded to the east by the Billefjorden Fault Zone and to the west by the Raudfjorden and the Kongsi]orden-Hansbreen Fault Zone, was in part a negative feature during Tournaisian and Visean time. However, in the Serpukhovian (Namurian) epoch this pattern was reversed and the block became strongly positive during Bashkirian-Moscovian time, when it was a sediment source, separating the East and West Spitsbergen Basins. It was overlapped by latest Moscovian strata, but continued to be positive, relative to the basins, until the end of the Carboniferous Period. Its effects decreased until hardly noticeable in Late Permian time. On the eastern margin of the block, there was a narrow axis of uplift in eastern Dickson Land, parallel to the Billefjorden Fault Zone and to some extent fault-bounded, which was the site of uplift and erosion during a Bashkirian/Moscovian episode. Gzelian strata show marked thinning across the axis.

Fig. 17.4. Schematic map of the structural framework mainly evident from Carboniferous and Early Permian time. Key to numbered faults: (1) postulated Palaeo-Hornsund Fault; (2) Kongsbreen-Hansbreen (part postulated) Fault; (3) Post-Carboniferous Pretender Fault; (4) Adriabukta Fault; (5) Inner Hornsund Fault; (6) Raudfjorden Fault; (7) Breibogen Fault; (8) Billefjorden Fault Zone; (9) Lomfjorden Fault Zone; (10) Storfjorden Fault Zone.

The West (Spitsbergen) Basin (St Jonsfjorden Trough). Thick Carboniferous sequences are preserved in scattered outcrops within the Paleogene orogenic belt of west Spitsbergen, which contrast in facies and thickness with those of the Nordfjorden Block. The rocks, which generally overlie pre-Devonian basement, are folded and thrust. In the west, they are sometimes highly deformed and somewhat metamorphosed. The apparent contrast between the West (Spitsbergen) Basin and its eastern neighbour may well be accentuated by the Paleogene eastward thrusting and folding of the platform sequence.

The Bjornoya Basin. Bjornoya lay on the southeastern margin of a NNW-SSE-trending rift or semi-graben from Famennian to Bashkirian time, bounded to the west by a major fault, the West Bjornoya Fault (Gjelberg & Steel 1983). This is probably an extension of the Palaeo-Hornsund Fault Zone (Fig. 17.4). This depositional basin may extend to the Barents Shelf between Bjornoya and Spitsbergen.

316

CHAPTER 17

The Inner Hornsund Trough postulated by Gjelberg & Steel (1981) shows a similar sequence and may be part of the Bjornoya Basin. The Sorkapp-Hornsund High developed on the western margin of the Inner Hornsund Trough in Bashkirian time on the site of a widespread shallow Early Carboniferous basin. This basinal inversion can be compared to that which occurred in Late Moscovian-Gzelian time, when there was uplift in eastern Bjornoya. Following latest Carboniferous uplift and erosion in southern Spitsbergen, the Permian Period was one of tectonic stability across much of Spitsbergen. The changing palaeogeographic regimes and transition to more stable platform environments probably reflects northward plate movement and the relocation of the tensional tectonic regimes that produced the major intracratonic rift structures. These dominated sedimentation during Carboniferous time, although there was continuing active uplift to the south. Four palaeo-tectonic elements thus can be recognized. (i) The Northern Platform is a hypothetical Permian land area to the north of Spitsbergen which may have been geomorphologically continuous with the Lomonosov Ridge of the present Arctic Basin. (ii) The Spitsbergen Basin was the main basin of deposition through Permian, Mesozoic and Paleogene time. (iii) The Sarkapp-Hornsund High was a positive ridge throughout Permian time in the south of Spitsbergen, the southern continuation of which is not known. The Tempelfjorden Group thins rapidly in southern Spitsbergen and the High separated the Permian sediments in south Sorkapp Land from the main development. Considerable amounts of clastic sediment were supplied as a result of this uplift during latest Carboniferous and Early Permian time (the Treskelodden, Hyrnefjellet and Reinodden formations), while over the rest of Spitsbergen, carbonates prevailed (in the Tyrrellfjellet Member and the Gipshuken Formation). (iv) The Bjornoya Basin. Bjornoya lay on the margin of a depositional basin. Shallow-marine shelf carbonate and clastic sedimentation was twice interrupted by tectonic upheavals, resulting in Early Sakmarian and Late Artinskian unconformities. Otherwise there are close stratigraphic parallels with the sequences of the Central Basin. The Tempelfjorden Group deposits on the southwest flank of the Hornsund High in Sorkapp Land may represent the deposits of the northern margin of this basin.

dividing the Dicksonfjorden and Ekmanfjorden areas. In the earlier publication a similar fault C is projected as the Pretender Lineament from a small fault trace which does not necessarily have a pre-Tertiary history, nor is it in line with the Raudfjorden Fault Zone. Authors addressing post-Devonian stratigraphic boundaries did not anticipate the Kongsfjorden-Hansbreen Fault Zone (KHFZ of Harland et al. 1993), or its predecessor the Central West Fault Zone (CWFZ of Harland & Wright 1979). They may be referred to together with the Pretender Lineament of Mork & Worsley as the (generic) 'West Spitsbergen Fault Zone'. They were postulated to bound the central and western provinces or terranes. This ancient fault zone, redrawn through Hansbreen in western Hornsund in 1993 (Harland, Hambrey & Waddams) fulfils the function of separating the West (Spitsbergen) Basin from the Nordfjorden High and from the Central Spitsbergen Basin further south. It also separates the Hornsund-Sorkapp High from the West Sorkapp Land Basin to the west.

17.3.2

For immediate practical use Mississippian is preferred to Early/'Lower' Carboniferous as being unambiguously Tournaisian+Visean+Serpukhovian. Mid-Carboniferous is unambiguously Russian and equals Bashkirian + Moscovian. Late Carboniferous is ambiguous being Kasimovian+Gzelian for the Russian usage, but more correctly should be Pennsylvanian (Bashkirian to Gzelian). Thus 'Middle' and 'Late' Carboniferous strata in Svalbard combine in Pennsylvanian. International stage or epoch names avoid these pitfalls.

Boundary faults

The terranes as outlined above are bounded by mainly preCarboniferous fault zones with a N N W - S S E trend. (i) Eastern (Svalbard) Platform. Lomfjorden Fault Zone (ii) East (Spitsbergen) Basin (including Billefjorden Trough) Billefjorden Fault Zone (iii) Nordfjorden Block. (a) Dicksonfjorden ?Breibogen Fault Zone (b) Ekmanfjorden Kongsfjorden-Hansbreen (postulated) Fault Zone (Fault C of Mork & Worsley 1979) approximates their Pretender Lineament in the north. (iv) West Spitsbergen Basin (including St Johnsfjorden Trough) ?Paleo Hornsund-West Bjornoya postulated Fault Zone (of Gjelberg & Steel 1983) The scheme above differs from those of Mork & Worsley (1979) and Steel & Worsley (1984). The southerly projections of their faults trend further to the southeast than those in Fig. 17.4. so that the two schemes cannot simply be translated. The more southerly trend of the Billefjorden Fault Zone in Fig. 17.4 is based on the subsurface section by Mann & Townsend (1989). In each case their fault C is projected SSE along the axis of the (Tertiary) Central Basin. In the later publication it extends the Breibogen Fault Zone, which had a Silurian to Early Devonian strike-slip history, but the only evidence from exposure would be in Ekmanfjorden so

17.4

Carboniferous and Permian time scale

Figure 17.5 is an attempt at an international geological scale. It is based on a study in 1989 (Harland et al. 1990) in which the stages/ epochs were nearing international agreement. At least three Carboniferous features are noteworthy, each of which arises from the different traditions in the Former Soviet Union (FSU), Western Europe, North America and Asia. Because Svalbard strata are generally easiest to correlate with the Arctic regions of the FSU the Russian tripartite division of Carboniferous time is commonly followed in which Mid-Carboniferous is understood as Bashkirian plus Moscovian. However 'Early Carboniferous' could refer (i) to pre-Bashkirian in the Russian sense; (ii) to Dinantian in the West European sense which includes only Tournaisian and Visean (Namurian being Serpukhovian and early Bashkirian as the earliest Silesian (late Carboniferous) epoch or (iii) Mississippian which is approximately Tournaisian through Serpukhovian. Harland et al. recommended Mississippian as having priority in this competition for a single international scale, but most writers on Svalbard geology simply refer to 'Lower' Carboniferous etc. from FSU usage. One distinction is that whereas coal measures in Western Europe tend to be Late Carboniferous in age (Silesian), the Dinantian being typified by Carboniferous limestone, the Svalbard sequence is the reverse with 'coal measures' the (original Kulm) being Tournaisian, Visean (& Serpukhovian).

Permian division also differs. In western Europe, where marine Permian strata are somewhat exceptional the Dyassic or two-fold division became established (and persists in the Chinese name for Permian) but the Permian System was set up by Murchison in the Russian Urals where a better marine sequence obtains and for long the Russian stages have been applied generally in Europe while dividing the period into West European Rotliegendes and Zechstein. However, the Zechstein (in Russia) passes upwards into continental red beds, which are difficult to correlate; so that Tatarian has little application and Kazanian not much more. On the other hand, the later Permian succession in North America is better based in marine strata so that Harland et al. adopted a Guadelupian epoch with Ufimian, Wordian and Capitanian stages. However, even in N o r t h America latest Permian time is not well represented and it turns out that in the eastern Tethys, and southern China in particular, richly fossiliferous marine faunas are younger than anything known in the west. This was the reason for introducing Lopingian for the Late Zechstein epoch because it can be well documented (Harland et al. 1990) but for the above reasons not easy to correlate elsewhere.

CARBONIFEROUS AND P E R M I A N HISTORY OF SVALBARD International

Some regional equivalents

I

w

Period

Stage

TRIASSIC I

Epoch / Stage

N

Spitsbergen

Russia EuropeIAmericaBj~rn~ya Fm

Griesbachian ? .~_

Gp

Age of boundary in Ma

Some index fossils Foraminifera 3rachiopod zonesI Palynomorphs

~,.,-vv , v ~ , . , ~

Changxingian

(Eastern Tethys)

o,

Longtanian

9t-

._~

Capitanian

"~.

.~

317

"o r

?

?

245 Paleofusulina -

~~o

~ =

Cap

~ ~_

(5)

Codonofusiella

- 250

cO iN

._~

~.

Wordian (.9

Ufimian

Wor

Kun

-~

"~ 0o

8

._~ =o

Artinskian

Sakmarian

(6)

Art

~

~

rY

Sak

~'~" I~-E Neoschwagerina Lissochonetes Cratianifera N. simplex Pseudosirena

o)

~.

E

=

-r"

.~ (5

,~

rY

Parafusulina

o

,~

Sowerbina Antignotunia Jakutoproductus

~* ~

%

Gzelian

.

~

o

~~o

~9

Kasimovian

(9)

(13)

Yakovlevia Q. ,~ PseudoTonuopsis ~ schwagerina Orlkotichia V e- Schwagerina Kichoproductus ? & ~ ' ~ ' .~~ T r i t i c i t e s ~

-6

Ass

-

282 (8)

T

- 290

I

(.o

256 (4)

~.~ - 269

Tornquistia Pseudofusulina Attenuatella

"~

-

- 260

=

Asselian

(13)

/

E ._~

"~ Yabeina O~ Lepidolina Verbikina

~ Ufil

~

Kungurian

~o ~

~

*~

303

Fusulina

~

Moscovian

(8)

g

c-

"g Atoken -

r

g n

Bashkirian

O

~

~

IM

(12) r ._

r

- 323

2 Serpukhovian

Z

(10)

..E

o El.

- 333 &

L Tournaisian

Fig. 17.& Carboniferous and Permian time scale and biostratigraphy, based mainly on Harland et al. (1990).

DEVONIAN

g

3=

Visean

_.1

Famennian

The above points are relevant in considering Svalbard correlation. The Templefjorden Group lacks diagnostic fusulines and ammonoids. Even in the more representative Arctic Canada the earliest Triassic faunas appear to follow Capitanian rocks with Cyclolobus. Western successions are affected successively by Variscan (Hercynian), Appalachian and Uralian orogenic episodes, the effects of which largely passed Svalbard by, as well as the North American Arctic. But the Lopingian epoch is still something of a mystery in the west (including Svalbard) and this lack of a historical frame vitiates much stratigraphic description. At the same time, if the calibration estimates are reliable, the latest Permian stages were of very short duration. A new question has arisen concerning the Lopingian division. It appears that it may overlap in time with the Early Scythian (Griesbachian stage). This may become clearer with conodont studies. This is a typical boundary problem where overlap or gap should now be settled by the 'golden spike' (GSSP) procedure. Once the Permian-Triassic boundary has been finally defined by GSSP the consequences will be automatic if the rocks can be correlated. Hitherto the North American succession has provided provincial GSSP for the period boundary. It is standard practice that the initial boundary of the later division shall ipsofacto be the terminal boundary of the earlier division in each case giving preference to the later division. However, until the matter is internationally agreed the question remains open.

:

311

Eofusulina

g g

g a E SZoo

z

g ~

(17)

o

350 Raritubereulatus

(13)

.M~

The reason for this digression is that Wignall & Twitchet (1996) have adopted the view that the earliest strata of the Sassendalen Group, traditionally Triassic, are Lopingian (Permian). This makes no difference to the geological interpretation and an international decision is awaited. Their significant contribution, however, is that the lower Sassendalen (Vardebukta) formation reflects anoxic conditions which might mark a Permo-Triassic biotic crises. This matter is discussed with the traditionally Triassic Vardebukta Formation in the next Chapter. Figure 17.5 lists the divisions that might be relevant for correlation of Svalbard rocks. There are seven epochs for the Carboniferous sequence which in Europe, at least, is divisible into 25 stages for effective correlation. International biostratigraphic correlation of Svalbard formations is n o t easy in spite o f the rich biotas. T h e Mississippian rocks are largely n o n - m a r i n e ; b u t rich p a l y n o l o g i c a l assemblages give r e a s o n a b l e ages t h o u g h n o t to stage level. E v a p o r i t e facies limit the possibilities o f precise B a s h k i r i a n age estimates. T h e r e a f t e r fusulines h a v e been reliable index fossils b u t are f o u n d in S v a l b a r d only u p to a b o u t S a k m a r i a n age. R u g o s e corals are also valuable, b u t are n o t precise indicators. T h e later rich b r a c h i p o d - b r y o z o a n - s p o n g e f a u n a s give little help. This distinctive T e m p e l f j o r d e n facies is nevertheless w i d e s p r e a d in the Soviet a n d C a n a d i a n Arctic. I n d e e d

318

CHAPTER 17

Stepanov (1937) proposed a Svalbardian Stage for it, of postArtinskian, possibly Kazanian age. It is a facies event difficult to date, and its age in terms of international stages has not been determined. Conodonts which are internationally valuable range only through to Bashkirian when Svalbard lacked suitable marine limestones. In an attempt to improve the correlation prospects for Svalbard's Permian strata, Mangerud & Konieczny (1991, 1993) made a thorough study of Svalbard palynomorphs. The facies were not appropriate and the material poor; nevertheless, the distribution of 95 species or forms through the representative sections resulted in the recognition of three Permian assemblages: Vittatina a s s e m b l a g e - latest Noginskian to mid-Asselian; Hamiapollenites tractiferinus a s s e m b l a g e - mid-Asselian to mid-Artinskian; Kraeuselisporites assemblage - mid-Artinskin to ?earliest Longtanian. Within the Billefjorden Group continental coal measure environments favoured vegetation and Playford (1962, 1963), from a study of 57 species distinguished two assemblages: Rarituberculatus (Tournaisian) and Aurita (Visean possibly to Serpukhovian). Thirteen species were c o m m o n to both and 21 and 23 species respectively characterized the two stages. The age of the Tempelfjorden Group, notably the Kapp Starostin Formation, has been a puzzle. The formation contains an abundant fauna, predominantly of silicified brachiopods, but also of bryozoans, bivalves, corals, sponge spicules, echinoderms, gastropods and foraminifers. Trace fossils abound, with Zoophycos, Teiehichnus and Chondrites. Szaniawski & Malkowski (1979) distinguished two time-equivalent fossil associations which represent different depths: the bioclastic limestone facies of near-shore, shallow-water, high-energy thicker-shelled species and an offshore, low-energy, deeper-water fauna dominated by sponges, with more fragile brachiopods and bryozoans, which occurs in the siliceous rocks associated with in-situ glauconite and pyrite. The brachiopod fauna is broadly comparable with the later Early Permian and Late Permian assemblages of the USSR (Tschernyschew 1898, 1902). However, many of the species have long time ranges and show considerable intraspecific variation which has caused confusion over correlation. Biernat & Birkenmajer (1981) found that at the base of the Kapp Starostin Formation in Torell Land, two brachiopod species were the same as those in Sakmarian-Early Kungurian rocks of Inner Isfjorden. Many species are closely related to the Artinskian or Kungurian species of the Former Soviet Union, but several genera characteristic of Late Permian also occur (Gobbett 1963). Ustritskiy (1962) and Burov et al. (1965) distinguished two separate faunas, both belonging to the Ufimian stage, in the 'Starostin Suite' (=Svenskeegga/Voringen Members) and 'Selander Suite' (=Hovtinden Member), the latter being distinguished by the presence of Cancrinelloides and Sowerbyna. These assemblages have not yet been recognized throughout Spitsbergen. A Kungurian age has been confirmed for the lower part of the formation (Nysaether 1977; Ustritskiy 1979) and a Ufimian age is indicated by the foraminifers for the small Permian inliers of Edgeoya, which represent a glauconitic chert facies (Pchelina 1977). The upper part contains brachiopods which extend into the Kazanian stage (Ustritskiy 1979) and Ustritskiy assigned the 'Starostin' (=the Voringen and Svenskeegga Members) and 'Selander' (--the Hovtinden Member) 'Formations' to Boreal stages (Paykhoyian and Early Novozeml'ian) which correlate with the Kungurian-Ufimian and Kazanian ?basal Tatarian respectively. Conodont assemblages also confirm a Kungurian-Ufimian age as they correspond stratigraphically to the Late Leonardian/Early Roadian of the USA (Szaniawskij & Malkowski 1979). As the formation is transgressive, lithological boundaries must be diachronous until open-sea cherty facies occur everywhere, i.e. at the top of the formation (Malkowski 1982). There is a stratigraphic gap in the Hornsund region, where the Voringen and Svenskeegga Members of the Isfjorden area absent. The possibility that Late Lopingian (i.e. Changxingian) might approximate the Early Scythian (Greisbachian) stage, as suggested by Wignall & Twitchett (1996), does not affect the age estimate of the youngest Tempelfjorden Group strata as discussed above. Therefore in any case the whole B/Jnsow Land Supergroup is latest Famennian, Carboniferous and Permian. The question remains as to the time span and the corresponding events of the interval between the Tempelfjorden Group (Kapp

Starostin Formation) and the Sassendalen Group (Vardebukta Formation). The base of the Vardebukta Formation, with the ammonoid Otoceras boreale, whether or not correlated with the conodont zone Hindeodus paroces, rests locally with disconformity on the Kapp Starostin Formation. Slight earth movement is evident locally. The corresponding hiatus might span later Capitanian and possibly Longtanian time.

17.5

Carboniferous and Permian sedimentary environments

The distribution in space and time of the rock units already introduced in their regional context in Chapters 4 5, 9 10 and 11 is shown in Fig. 17.3. Formational boundaries are not expected to coincide with standard chronostratigraphic boundaries, but for convenience of description they may be approximated as below. Lithological and biostratigraphic details appear in the regional formational descriptions. This section outlines environmental interpretations in time sequence. The conclusions of these interpretations is applied in Section 17.7 'Tectonic controls of sedimentation'.

17.5.1

Late Famennian-Tournaisian-Visean-Serpukhovian deposition (Billefjorden Group)

The Billefjorden Group is dominated by continental sediments of fluviatile swamp and lacustrine origin. Coal-bearing members indicate a humid climate. The only evidence of any marine influence is in Broggerhalvoya (Western Basin) and in southern Spitsbergen.

Horbyebreen Formation (Billefjorden Trough). The Horbyebreen Formation lies unconformably on Proterozoic basement rocks in Dickson Land and southern Ny Friesland. It is variable in thickness from 57 to 200m thinning to the west. The complete absence of marine fossils and the abundant plant remains indicate a continental environment. The formation was probably deposited in a small, elongate basin, partly fault-bounded in the east, as the formation is absent east of a line between Austfjorden and Billefjorden except for some possible outliers east of Austfjorden (Harland 1941). In Ebbadalen and on Terrierfjellet, the overlying Svenbreen Formation rests directly on Pre-Devonian (Hecla Hoek) basement. The eastward increase in clast size in conglomerates of the Triungen Member and in coarser lithologies in the Hoelbreen Member suggests a sediment source to the east, perhaps a result of upfaulting of the Ny Friesland region and its Hecla Hoek basement. However, palaeocurrent analysis suggests a second contemporaneous source area to the west and probably south (Gjelberg 1987). Gjelberg & Steel (1981) and Gjelberg (1987) suggested that the arenites and rudites of the Triungen Member represent braided stream with overbank deposits, whereas the mudstones may be lacustrine. The Hoelbreen Member, in contrast, appears to have been dominated by northward-flowing, high sinuosity meandering streams in a large, swampy, densely-vegetated floodplain environment where finegrained, organic-rich sediments accumulated (Abdullah et al. 1988). Channel fill, levee, crevasse channel and splay, point bar and flood basin deposits are all preserved within the sequence, but no distributary channel deposits have been identified. Plant debris appears to be concentrated in the east, probably nearer the source. Coal occurs as thin beds with seat-earths and rootlet beds, interbedded with shales and siltstones. They may represent the local development of coal-swamp conditions on the floodplain. The Hoelbreen coals are humic, low in ash and sulpher, and enriched in vitrinite. They are hydrogen-rich with up to 15% liptinites. Selaginella-rom megaspores and thick-walled spores are common (Michelsen & Khorasani 1991). The eastward increase in grain size and thickness, together with the lack of distributary channels, points to a faulted eastern basin margin. Downthrow may have encouraged flooding (Gjelberg & Steel 1981) and restricted the river system to near the basin margin, such that distributary channels are probably preserved to the east of present exposures, where subsidence was greatest (Gjelberg 1987). The general thinning to the west suggests a western margin in the region of Dicksonfjorden.

C A R B O N I F E R O U S A N D P E R M I A N HISTORY OF SVALBARD

Mumien Formation (Billefjorden Trough). The Mumien Formation is a terrigenous unit present in the Billefjorden area, with a thickness of up to 230 m. It contains two members: Sporehogda and Birger Johnsonfjellet. The Sporehegda Member contains massive coarse sandstones with minor shales and allochthonous coal, whereas the Birger Johnsonfjellet Member contains numerous coal seams within a predominantly shale and siltstone sequence. Deposition of this formation was mainly within a rather restricted elongate basin, with the thickest deposits along the line of the BiUefjorden Trough, where subsidence was greatest (Fig. 4.12). Pre-Bashkirian uplift and erosion has further restricted the formation, but the original basin may not have been more than 45 km across if both members are indeed recognizable in the thin sequence at Terrierfjellet (Fig. 4.10). There is no evidence of marine incursions, so the sediments must be of fresh or brackish-water origin, a conclusion backed up by the abundant plant debris. The sandstone units, with their signs of rapid deposition, such as cross-bedding, wash-outs and slump structures, and their rapid lateral thickness variations, are interpreted as the channel deposits of rivers. Meandering channel migration on a poorly drained floodplain with swamps and lakes would produce the cyclic sandstone/siltstone/shale sequences. The finer sediments, including the carbonaceous material, could settle out in quiet water with coals forming locally where plant material accumulated. The lack of seat-earths suggests that they are allochthonous. A lake origin for the upper coals is supported by organic petrological studies. There was a change in the mid-Birger Johnsonfjellet Member from a peat swamp environment to lacustrine conditions with deposition of rich cannel and boghead cannel facies upwards. This corresponds to the time of active normal faulting to the west of Pyramiden. (Abdullah et aL 1987; Michelsen & Khorasani 1991). The appearance of conglomerates locally in the upper member may also be due to movements along thc East Dickson Land Axis. No palaeocurrent directions are known from the fomaation, so the source area can only be guessed at. The general absence of conglomerates, suggests it was fairly distant. A source to the west would mark the onset of uplift of the Nordfjorden Block. However, the underlying formation has evidence of both eastern and western provenance (see above). Orustdalen Formation (Western Basin). Sandstones and shales are the predominant constituents of this formation, which varies in thickness up to several hundred metres. The lithology, abundance of plant remains and total absence of marine fossils indicates a continental, predominantly fluviatile environment in a humid climate. In Broggerhalvoya Fairchild (1982) recognized three facies. (i) A fluvial channel facies consisting of interbedded conglomerates and cross-bedded sandstones which he interpreted as a series of braided river channel deposits with flow directions to the south and west. (ii) An overbank facies of shales, which become more important upwards, containing some in situ, but mostly drifted plant remains. This facies is scarce in the section containing the third facies. (iii) A marine reworked sandstone facies occurs at several levels in one section only, grading up from the fluvial channel facies. Medium-coarsegrained, cross-stratified sandstones contain unimodal and bimodal current directions, which are indicative of reworking of the fluvial sandstones by waves or tides. Conglomerates are not known. In this area, Fairchild concluded that the sediments were deposited onto coastal alluvial fans derived from a fault scarp to the northeast, uplifting a siliceous Early Paleozoic source. The paucity of fine material is attributed to the nature of the source. Other source areas certainly included pre-Devonian basement on which the formation rests and there is evidence of Devonian elements in the conglomerates (Dineley 1958). Evidence from the Billefjorden Group around Billefjorden suggests that there was uplift of the Nordfjorden Block at this time. Although there are basal conglomerates locally, they have been reworked and sorted. The basement rocks have been channelled and thoroughly planed (Dineley 1958; Flood 1968). Vegardfjella Formation (Western Basin). The Vegardfjella Formation consists of sandstones with carbonaceous shales and subordinate conglomerate. The lithologies, with their total absence of marine fossils and abundant plant fragments, suggest a continental fluviatile/lacustrine environment, the shales representing the latter. Adriabukta Formation (South Spitsbergen). Unconformably overlying Devonian basement, the Adriabukta Formation consists of at least 500m of black, dark grey and green shales. The formation was deposited to the east of the Inner Hornsund Fault Zone, and overlaps underlying formations to the west and to the north. It is relatively thick and may have had quite a

319

considerable extent to the east and south. The local mid-Carboniferous erosion of the top of the formation was probably due to movements on this fault, which may also account for the sudden marine to continental environmental change between this and the overlying Hornsundneset Formation. As the bottom of the sections on Hyrnefjellet contain a recognizable benthonic fauna, as well as plant remains, it would seem that this part of the formation was deposited in a shallow, near-shore marine environment. A fairly high energy level is indicated by the abundant conglomerates and sandstones showing signs of cross-bedding. Crossbedding in the basal clastics suggests a relatively close sediment source to the east (Gjelberg & Steel 1981). The main shale sequence, in contrast, yielded no fauna and seems to represent a quite different environment of quiet, anaerobic conditions in a restricted basin. The thin, poorly sorted or graded sandstone beds and conglomerate lenses were probably brought from shallow, marginal areas by occasional mass-flow/turbidity currents. These were possibly triggered by movements on the boundary faults of this basin, the Inner Hornsund Fault and the extension of the Billefjorden Fault Zone. The main shale sequence is neither carbonaceous nor coal-bearing like other Billefjorden Group shales, a fact explicable if it represents a marine basin, in which the absence of fauna implies anaerobic or restricted conditions.

Hornsundneset Formation (South Spitsbergen). Up to 750 m thick, this is the thickest and most coarse-grained unit of the Billefjorden Group in southern Spitsbergen. Clasts are derived from Precambrian basement. Plant remains are common and thin coal seams are present in places. Birkenmajer (1979) considered that the rather polymodal cross-bedding directions point to meandering river-channel deposits. Gjelberg & Steel (1981), however, favoured braided streams associated with a widespread series of alluvial fan systems. The source was to the west and/or northwest. Most of the clastic material is derived from a distant source and not local to southern Spitsbergen. The only local material is in the pebble-lag conglomerates. The finer deposits, which are a minor component, represent alluvial-plain overbank sediments. Marine faunas and calcite cement are not recorded. Sergeijevfjellet Formation (South Spitsbergen). The Sergeijevfjellet Formation consists of approximately 180 m of shales with fine-grained sandstones and siltstones. The sandstones are cross-bedded in places, the shales contain abundant plant debris, and thin coals are common. They were clearly deposited in a fluvial environment with localized flood basins and swamps. Roedvika Formation (Famennian and Tournaisian of Bjornoya). At the base of the Billefjorden Group on Bjornoya, the Roedvika Formation is a elastic sequence up to 360 m thick. The base, and possibly also the top, are unconformable; it rests on Precambrian and Ordovician basement. It has been divided into three members. The lower and middle parts of the Roedvika Formation constitute a single upward-coarsening sequence from the coal-bearing Vesalstranda Member to the coarser Kapp Levin Member. Facies analyses by Worsley & Edwards (1976) and Gjelberg (1978, 1981) all concluded that lacustrine, deltaic and fluviatile environments prevailed. The lakes provided conditions suitable for coal formation. As no true seat-earths have been found, the coals are probably allochthonous. There is no evidence of marine influence in the Roedvika Formation. Cross-bedding shows a great diversity of flow directions, although a general palaeoslope to the north is indicated (Worsley & Edwards 1976; Gjelberg 1978). Calcrete or desiccation cracks have not been reported so it may be concluded that the climate was moist. The Vesalstranda Member (Late Famennian) consists largely of floodplain sediments and shows an overall progradational trend from lacustrine/ deltaic up to fluviatile environments, though the thinly developed basal conglomerate may represent braided streams. The lacustrine/deltaic association consists of crevasse, channel and mouth-bar sediments organised into small upward-coarsening sequences indicative of delta lobe progradation, presumably into lakes. Fluvial sediments become more common upwards, with upward-fining, meandering river/floodplain associations of sandstones, siltstones and mudstones, representing fluvial channel, levee/channel fill and floodplain facies. Palaeocurrent evidence suggests a source to the southeast. The Kapp Levin Member (Early Tournaisian) represents the culmination of this basin-filling episode, containing the coarser-grained deposits of lowsinuosity braided streams which probably flowed to the east or northeast. The overall change in depositional environment and palaeocurrents seen through this upward-coarsening sequence is probably related to the increasing dominance, with time, of lateral alluvial fan systems building out from the southwest margin of the basin over the northwestward-flowing axial fluvial channels (Worsley et al. 1987). The shales at the top of the

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C H A P T E R 17

member mark an abrupt change in depositional environment. The entire basin may have been suddenly covered by a lake, perhaps because of a sudden lowering of the base level as a result of faulting. The Tnubeim Member (later Tournaisian) represents the re-establishment of floodplain environments and the start of a second depositional phase. Channel deposits predominate in the lower part, while finer overbank, coal-bearing shales are characteristic of the upper part. The visible splitting of the upper unit northwards suggests an increase in subsidence in this direction. The member contains the deposits of north- or northwest-flowing meandering rivers. Studies of the plant fossil Pseudobornia ursina, which occurs in this member, indicate the presence of bodies of water, along the shores of which the plants grew in rather pure stands (Schweitzer 1967). The lowermost coal seam shows a systematic increase in vitrinite content from floor to roof where the seam splits. Coals are commonly pyrite rich. The next lowest seam is thin and enriched in inertinites and all contain up to 5% meta-lipinites (i.e. Sporinite matured to near vitrinite. They are of prime coking rank (R0 = 1.34%)

Nordkapp Formation (Visean of Bjornoya).

The Nordkapp Formation is the uppermost unit of the Billefjorden Group on Bjornoya. It is up to 120 m thick. Gjelberg (1981) suggested that the lower sandstones represent braided stream deposits on the distal part of an alluvial fan system, with crossbedding indicating a sediment-source to the southwest. Soft-sediment deformation structures point to an active fault nearby (on the West Bjornoya Fault Zone?), perhaps producing an elevated area to the southwest. The features of the conglomerates of the upper unit are characteristic of debris-flow and stream-flood environments and may represent rejuvenation of the alluvial fan system, still prograding northeastwards. The conglomerates may mark the renewal of activity on the West Bjornoya Fault Zone (Gjelberg 1978), which then continued to be active into ?Bashkirian time. It is consistent with the sedimentological evolution postulated for the overlying Landnordingsvika Formation. The finer and carbonaceous sediments must represent flood-basin or lacustrine areas in this fan complex. The sequence was deposited in a relatively moist climate, with a high water table, resulting in reducing conditions and the development of coal and clay-ironstone horizons (Gjelberg & Steel 1981). The exposures of the north coast suggest that there was a transition to the red-beds of the Landnordingsvika Formation. This would impose such a long time span on the Nordkapp Formation that there may have been breaks in deposition, e.g. between the lower and upper parts of the formation (Gjelberg 1981).

17.5.2

B a s h k i r i a n - M o s c o v i a n - K a s i m o v i a n deposition (lower Gipsdalen Group)

By this t i m e the c l i m a t e was m o r e arid. R e d beds are c h a r a c t e r i s t i c o f the l o w e r G i p s d a l e n G r o u p , w i t h c o a s t a l m a r i n e facies c o n t a i n ing e v a p o r i t e s a n d c a r b o n a t e s . T h e e n v i r o n m e n t o f this interval was discussed b y L u d w i g (1989).

Campbeliryggen Subgroup Hultberget Formation (Billefjorden Trough). This unit marks the beginning of red facies in the trough. It is dominated by variable sandstones. Ebbadalen Formation (Billefjorden Trough).

The Ebbadalen Formation is one of the best known lithostratigraphic units of Svalbard. The total thickness of the formation is about 750 m but this decreases to the east away from the fault to zero. Described by Holliday & Cutbill (1972), Gjelberg & Steel (1981) and Johannessen & Steel (1992) the overall setting of the basin appears to have been one of a narrow basin, with deposition occurring in a half-graben against the Billefjorden Fault Zone. The Ebbaelva Member had a fluvial component, with braided stream, playa lake, lagoon, sabkha and barrier shoreline deposits represented. Marine conditions, indicated by marine fossils and sulphates, occur towards the top of the unit and represent occasional, sudden changes in relative sea level, within an overall transgressive regime. The Trikolorfjellet Member and the laterally equivalent Odellfjellet Member represent open-basin and alluvial fan deposits respectively building out from the Billefjorden Fault Zone. Close to the fault zone the red beds are conglomeratic, clasts being mainly composed of quartzose debris reworked from the Billefjorden Group. These alluvial fan deposits formed

in an arid marginal-marine environment. To the east, finer-grained and better-sorted sandstones in the Odellfjellet Member suggest fan-delta, shoreline and aeolian environments marking an arid alluvial plain with occasional marine incursions. Further away from the fault zone, the sandstones are transitional to shales with gypsum nodules, and then into the gypsum-anhydrite facies of the Trikolorfjellet Member. These deposits represent a change into warm to arid lagoon and sabkha environments. Eastwards, carbonates increase and become dominant over the evaporites which disappear entirely at the top, marking intertidal and open marine environments. This is especially so in the extreme east, where offshore skeletal limestones make up the whole of the highly attenuated section. Subsidence in the Billefjorden Trough was greatest near to the faulted western margin, decreasing gradually towards the eastern shelf sea area. Occasional marine transgressions, possibly as a result of fault movements, gave intervals of carbonate sedimentation over the entire basin. The alluvial fan sequences normally have a quartzitic beach-capping, which is in turn overlain by dolostone. Provenance of the formation is difficult to specify. Cross-stratification is varied, but indicates currents from the south. Clasts of Precambian biotite schist occur, probably also indicating a source to the south. Tournaisian and Visean spore assemblages found in shale clasts are probably derived from rocks of that age to the west, and may represent uplift on the East Dickson Land Axis. Hence, the source may have been to west and south.

Minkinfjellet Formation (Eastern Basin east of Billefjorden Fault Zone). The Minkinfjellet Formation is present in the Billefjorden area only. It is a variable unit with rapid lateral and vertical facies variations. It has a thickness of 300 400 m with its maximum adjacent to the Billefjorden Fault Zone, corresponding to the area of greatest subsidence. The deposition of the formation was largely controlled by subsidence within the Billefjorden Trough, bound to the west by contemporaneous faulting and flexuring along the Billefjorden Fault Zone. There are also prominent northsouth facies belts parallel to the trend of the fault zone. It is likely that the environment was similar to that for the underlying Ebbadalen Formation. Clastic sequences may represent continental fluvial fan deposits, but interbedded carbonates and evaporites indicate a marginal situation with frequent marine transgressions. The evaporite zone represents coastal sabkha environments, but pure sulphate is somewhat restricted and the sequence contains a higher proportion of lagoonal dolostone. Further east, the thinner carbonates represent more open marine conditions and marine sandstones become an important constituent eastwards. The breccias of the Fortet Member probably represent either seismically-induced in situ brecciation due to movement on the Billefjorden Fault zone, or local erosion of the fault scarp.

Hhrbardbreen Formation (Nordaustlandet). Unconformably overlyingPrecambrian basement, the Hhrbardbreen Formation is only 15 m thick, of which the bottom 8 m is a basal conglomerate. The remainder consists of lightcoloured quartz-rich cross-bedded sandstone with conglomerate layers. It is a shallow marine unit, probably deposited in the inter-tidal zone, and represents a transgression over basement. Charlesbreen Subgroup Broggertinden Formation (Northern Oscar II Land).

The Broggertinden Formation is a 350 m thick unit of sandstones and conglomerates that is correlated with the Ebbadalen Formation of the Billefjorden area. The cyclic nature of the deposits and their red colouration, the general absence of marine fossils and the rare occurrence of carbonates plus the presence of fish fragments suggest fluvial deposition. Current directions are variable. They are from the south and east at Scheteligfjellet, but the regional drainage pattern must have been towards the south if the Petrellskaret Formation is coeval. Stratigraphic relationships across the Kvadehuken Fault indicate that uplift occurred to the east of the fault during deposition.

Petrellskaret Formation (Southern Oscar II Land).

This formation consists mainly of shales and mudstones approximately 350 m thick. The generally fine character of the formation, the purple colour, calcareous nodules and rarity of marine fossils suggest deposition on a coastal alluvial plain with a dominance of overbank sediments, or perhaps an interdistributary bay. The sandstones, with their well-defined upward-fining and sharp bases could be crevasse-splay deposits. There was some marine influence at the base, where limestone and evaporites occur, and again near the top, so the area must have been marginal to the sea, allowing occasional marine incursions and deposition of limestones and evaporites. The dark shales at the top may be lacustrine or lagoonal.

CARBONIFEROUS AND P E R M I A N HISTORY OF SVALBARD

Scheteligfjellet Formation (Northern part of Western Basin). This formation consists of carbonates, calcareous sandstones and conglomerates forming sequences up to 150m thick. The formation must represent a marine transgression into the area. The absence of lime muds, the abundant coral growth and the frequent signs of local erosion are evidence of shallow agitated water (Holliday, 1968). A nearby landmass is indicated by the presence of sandy beds and pebbles in the limestones. The basal conglomerates could be littoral deposits. Holliday interpreted them as intertidal. Barbaroux (1968) recorded current directions from his 'Leinstranda Formation' from the northeast and southeast. This is not inconsistent with other evidence such as the general increase in clastic content to the southeast and the presumed lateral transition to the clastic deltaic T~rnkanten Formation to the south. In general, the formation represents a nearshore, marine environment with more normal offshore marine conditions to the north. T~rnkanten Formation (Southern Oscar II Land and Nordenski61d Land). The T~rnkanten Formation is up to 250 m of mainly quartz arenites with minor conglomerate, shale and limestone. The sedimentary features and red colour of the formation imply deposition in a coastal or intertidal environment. The cycles begin with deposition of channel sandstones and conglomerates with interbedded overbank or interdistributary shales. The overlying sandstones, conglomerates and shales show more evidence of marine influence, being calcareous and containing thin limestones and rolled fossils. An intertidal situation and a hot, dry climate would account for the contorted bedding, the mudcracks and the calcareous concretions. The period of deltaic build-out may have been terminated by widespread marine transgression, or simply channel-switching, allowing the deposition of fully marine fossiliferous limestones before a further clastic influx.

Treskelen Subgroup Hyrnefjellet Formation (inner Hornsund in south Spitsbergen). Exposed throughout the Hornsund area, the Hyrnefjellet Formation is variable in thickness from 30m to 500m. It is dominated by red-beds, mudstones, sandstones, conglomerates and breccias. The formation represents fastflowing alluvial-fan/fluvial sediments deposited under continental oxidising conditions in a warm, arid climate, on a pediment of deeply weathered and eroded Adriabukta Fm. The increase in rudites to the west and palaeocurrent measurements suggest that sediments were derived from an uplifted landmass in that direction (Gjelberg & Steel 1981; Birkenmajer 1984) which exposed pre-Devonian and possibly Devonian rocks. Lack of plant remains or coal point to a warm, arid climate. Such conditions favour accelerated diagenesis with migration of silica, and precipitation of iron oxide. Carbonates and sulphates were deposited as cement during early diagenesis, mainly in the upper part of the formation. This has a significance for correlation, as Bashkiria~Moscovian evaporites occur associated with redbed conglomerates in central Spitsbergen, in the Pyramiden Conglomerates (Ebbadalen Formation). In view of the contrasting intercalations of mature sandstone, and also the fact that littoral marine conditions prevailed in the overlying Treskelodden Fm, they were probably marginal to a shelf sea. The red colouration suggests a continental or marginal marine environments. Steel & Worsley (1984) regarded them as alluvial deposits which built out eastwards from the Hornsund High into a marine sedimentary basin, the Inner Hornsund Trough, which is largely concealed by younger rocks. The basal breccia-conglomerates probably represent debris-flow; the sandstone clasts appear to be intraformational, while the quartz pebbles are probably recycled. The sandstone-conglomerate cycles represent distributary channels and the siltstone-shale facies represents overbank deposits. A major distributary channel has been recognized at Urnefjellet (Birkenmajer 1984), characterized by the predominance of conglomerates over sandstones and overbank facies, the latter forming a substantial part of the sequence around Adriabukta and north of Hyrnefjellet. Each cycle was interpreted by Gjelberg & Steel (1981) in terms of gradual alluvial fan-gravel outbuilding over an alluvial coastal plain, followed by sudden marine transgression, which reworked the surface of the alluvial fan to form a thin quartzitic beach-capping. Birkenmajer (1984) interpreted the pale quartzitic sandstones as point-bar deposits. Clastic marine sediments increase in volume upwards towards the overlying Treskelodden Formation. The cyclicity is interpreted as sudden basin-floor lowering against the basin's boundary faults, resulting in marine transgression, with subsequent alluvial fan outbuilding. The mass flow conglomerates in the south suggest a fault line south of Adriabukta, probably part of the Adriabukta Fault Zone between the Inner Hornsund Trough and the Hornsund High.

Landnordingsvika Formation (Bjornoya). The formation is the lowest part of the Gipsdalen Group in Bjornoya, and as elsewhere it is marked and indeed

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characterized by the appearance of red-beds up to 145 m thick. The red colouration and upward-fining cycles with calcrete and mudcrack development suggest deposition on an alluvial plain in semi-arid conditions. A coastal situation is indicated by the appearance of marine fossils and limestones towards the top. Analysis of cross-bedding indicates that the rivers were northward flowing and sinuous, giving a variety of current directions. Conglomeratic alluvial fans built out eastwards in the middle part of the formation, probably as a result of movements along the West Bjornoya Fault Zone. A source to the south is also suggested by the more distal nature of the sediments in the north. These are less conglomeratic and represent a prograding sandy shoreline, with tidal flat and lagoon deposits interdigitating in the upper part in a transition to the overlying Kapp K~re Formation. Gjelberg (1981) and Gjelberg & Steel (1983) showed the formation to consist of a variety of facies sequences ranging from floodplain facies which dominate in the lower part, through alluvial fanglomerates to tidal flat and coastal lagoonal sequences, followed by foreshore-shoreface and carbonate facies. One of the latter has been interpreted as lagoonal, protected behind a barrier, where solution and fresh-water diagenesis could occur (Gjelberg & Steel 1983).

Kapp K~re Formation (Bjornoya). The formation is a carbonate-dominated unit up to 170m thick. The formation was deposited in tidallyinfluenced marginal marine environments varying from lagoonal to open marine. The two lower members show the continuing effects of the regional transgression, heralded by the sequences in the upper parts of the Landnordingsvika Formation, with a transition from clastic to carbonatedominated sedimentation and a generally upward-fining trend, resulting from an ongoing regional rise in sea-level. The rhythmic sequences of the lower member, with their faunas indicative of a variation between marine and brackish water, may represent minor deltaic progradations. The good state of preservation of the corals implies little transport or reworking. The entire Bogevika Member reflects deposition in a marginal marine environment with repeated shoreline progradations and sub-aerial exposure. The abundant discontinuity surfaces suggest that the ryhthmicity may be due to the local tectonic activity. The few variable palaeocurrent measurements obtained may reflect both longshore and bimodally directed on/offshore tidal currents (Worsley et al. 1987). Microfacies and fauna suggest that the Efuglvika Member carbonates were deposited under more constant marine conditions, on a carbonate shelf of moderate depths, but intermittent periods of erosion and emergence, probably due to fault movements, must have occurred to produce the karst and discontinuity surfaces. The directional trends of the karst features and the chert dykes suggest that this tectonic activity was related to the new basinal pattern clearly seen in the overlying units. The intraformational conglomerates of the Kobbebukta Member have been interpreted as both sub-aerial and submarine debris-flows, triggered by syn-sedimentary faulting immediately to the east of the present exposures of the Kobbebukta and Efuglvika members (Bjoroy, Mork & Vigran 1983). This is considered to be a major new lineament through the east of the island, producing inversion of parts of the previous basins (Worsley 1985, 1988). Kapp Hanna Formation (Bjornoya). The Kapp Hanna Formation is a predominantly arenaceous unit. The unit represents marine, near-shore environments associated with coastal and floodplain deposits, which are the result of alluvial fan progradation into a marginal marine environment. The sedimentology is complex: marginal marine, tidal flat and lagoonal sequences were eroded by westward-flowing rivers which deposited alluvial fan and channel complexes of thick sandstones and conglomerates. These show debris-flow and braided river characteristics (Bjoroy et al. 1983; Agdestein 1987). Better-sorted intertidal and beach sediments contain clayclasts, desiccation cracks, marine fossils, bioturbation, lenticular and flaser bedding and have bimodal cross-bedding directions (Agdestein 1987). The fossils in the shales suggest deposition in brackish lagoons subject to periodic marine incursions. Fault movements both increased the clastic input and changed relative sea levels, causing either progradation (upward-coarsening) or marine transgression (upward-fining) on the NNE-SSW-trending shoreline, depending on which factor was dominant. Palaeocurrent data from the coastal alluvial clastics clearly indicate an eastern source area and Bjoroy et al. (1980) postulated uplift east of a NE-SW trending lineament intersecting the area, with erosion of Early Mississipian and older rocks. The mineralogy of the clastics suggests that the present day-exposure patterns of Carboniferous and earlier rocks on Bjornoya were largely established during the deposition of this formation, rather than in subsequent Permian tectonism. The existence

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of this upfaulted block in eastern Bjornoya was first recognized in the uppermost Kobbebukta Member of the underlying formation. The unconformities and erosion surface suggest that this movement continued sporadically during deposition of the Kapp Hanna Formation. The in filled fissures may be evidence of syndepositional earthquakes. Greater stability, coupled with decreasing elastic supply, resulted in an overall upward-fining trend and the establishment of a stable shelf environment.

17.5.3

Kasimovian-Gzelian-Asselian--Sakmarian deposition (middle Gipsdalen Group)

C a r b o n a t e s d o m i n a t e the m i d d l e o f the G i p s d a l e n G r o u p , deposited in w a r m shallow seas. In s o u t h e r n Spitsbergen, cyclic s a n d y deltaic facies are interspersed a n d locally s u l p h a t e s occur.

Dickson Land Subgroup Wordiekammen Formation.

The lower part of the formation comprises the laterally equivalent Cadellfjeilet Member (Billefjorden Trough), Kapitol Member, and Morebreeu Member (Oscar II Land) the former two being overlain by the Tyrrellfjellet Member in the central and western basins of Spitsbergen (Nordfjorden Block). The Cadellfjellet and Kapitol members consists of a sequence of Late Carboniferous limestones (locally dolomitic), occurring widely across Oscar II Land, James I Land, Dickson Land and Btinsow Land. It reaches 200m thickness in the Billefjorden area. The formation represents quiet, stable marine shelf conditions of normal salinity with the deposition of lime muds. Terrestrial influence increased to the east towards a presumed land area, where coarser-grained, recrystallized limestones occur and become sandy, passing into calcareous sandstones. Conditions of high salinity were locally reached in this region with gypsum deposition, perhaps in coastal sabkhas. Primary dolomite may have been formed locally. TyrrellfjeUet Member (Central and Western Basin of Spitsbergen), 160 m. The Tyrrellfjellet Member is a widely developed carbonate sequence of Early Permian (Gzelian-Asselian-Sakmarian) age, occurring at the top of the otherwise Carboniferous Wordiekammen Formation. There appears to have been minor uplift of the entire area around the Carboniferous-Permian transition, resulting in the widespread development of discontinuity surfaces and intraformational conglomerates, probably on reef margins. Renewed transgression led to the establishment of open marine environments with shelf carbonate deposition. Some restriction of circulation may have led to the deposition ofdolostones, especially in the upper part of the formation. In the northwest, there is much primary lagoonal dolomite, perhaps indicative of a nearby landmass. However, dolomitization is clearly secondary in many areas. To the east and north, increased sandstone content indicates terrestrial source areas. Although there are no significant thickness variations over the margins of the blocks which dominated Carboniferous palaeogeography, shoals and bioherm buildups still tended to develop at those sites suggesting continued subtle controls on sedimentation by downwarping along their boundary faults. The bioherms, which were described from the lower part by Skaug et al. (1982), extend from the eastern margins of the Nordfjorden Block, across the Biflefjorden Fault Zone and several kilometres out into the Billefjorden Trough. They formed an effective barrier to open marine conditions allowing lagoonal environments and dolomite deposition to develop behind them. Hardgrounds have been described at the base of each bioherm, showing signs of freshwater leaching and palaeosol development considered to have been formed in an intertidal environment. This environment is consistent with the presence of desiccation cracks and intraformational conglomerates elsewhere. They show regressive cycles with hardground development at the top prior to a transgressive biostrome build-up phase. Idunfjellet Formation (Nordaustlandet). Up to 150 m thick, the formation consists of limestones and dolostones with minor sandstones. The fossil content indicates an open marine, carbonate shelf environment with input of terrigenous quartz at both top and base. There is evidence of shallowing, with numerous erosive surfaces and intraformational conglomerates in the upper part. Diametrically opposed cross-bedding suggests a tidal influence. Dolomitization appears to be secondary. The chert nodules in the upper part could indicate an originally evaporitic environment, as they are similar to gypsum and anhydrite nodules which occur elsewhere in Svalbard (Lauritzen 1977). There is now no trace of sulphates, but the nodules may

indicate supratidal conditions. Gypsiferous layers also occur in the eastern outcrops of the Cadellfjellet Formation. Micritic and shaly beds point to low-energy, protected situations.

Treskelodden (Reinodden) Formation. Its thickness is variable and reaches 200 m in places. (a) Hornsund. Both marine and continental environments have been recognized in this 185cm thick formation (Birkenmajer 1979c, 1984d; Fedorowski 1982). The cyclic carbonates and elastics of the upper part, following the conglomeratic lower part, suggest a fan-delta system prograding into the sea, presumably from the margin of the Hornsund High (Kleinspehn et al. 1984; Birkenmajer 1984c; Steel & Worsley 1984), though Birkenmajer's current directions imply a predominantly easterly source. Birkenmajer recognized a basal unfossiliferous alluvial facies that is overlain by shallow marine facies. The former has distributary channel deposits (sandy conglomeratic channel bars and conglomeratic channel lags) containing wedge-shaped and planar cross-bedding and alluvial delta (overbank) deposits of clay, shale and siltstone with subordinate crevasse-splay sandstone. The succeeding subtidal to intertidal facies is fossiliferous and contains sandy offshore bars and a probably submerged delta, (cross-bedded and rippled), tidal channel fills (conglomerate and sandstone) and carbonate platform sediments (mainly subtidal calcarenites and arenaceous limestones). Interspersed are lagoonal facies deposits of carbonate-rich elastics and unfossiliferous carbonate (dolostones and dolomitic limestone), the fills of restricted basins, which may have been hypersaline. Above the first cycle, which is alluvial, are four cycles starting with tidal channel and shallow marine deposits (conglomerate and biogenic limestones) that cut into the top of the preceding cycle. These show more alluvial characteristics upwards with evidence of emergence at the tops of some cycles (mudcracks) which, associated with finer sediments, correspond to overbank and lagoonal deposits. There is an increasing marine influence higher in the sequence as the tectonic environment stabilized. There is evidence from the abundant coral fauna for warm, shallow seas. The fauna were redeposited under the high-energy conditions prevailing during deposition of the calcites, with submarine erosion and channelling by tidal currents. Palaeocurrent measurements are variable and indicate sources of alluvial elastics to be lying mainly to the east, but also to the west (Birkenmajer 1984c). The quartz conglomerate noted south of Hornsund at Bautaen was derived from the east (Gjelberg & Steel 1981) and may be a beach deposit. The major cycles could be eustatic, but could equally be a result of distributary channel switching. (b) Bellsund (e.g. at Reinodden). Nysaether (1977) concluded that the cyclic nature of the Reinodden Fm was probably due to fluctuations in sea level (cf. the palaeoaplysinid bioherm regressive sequences in the Tyrrellfjellet Fm to the north) rather than deltaic influence as there is no evidence of channels. Worsley (Aga et al. 1986) regarded fan-delta systems to be responsible for the elastic input, derived from the Hornsund High. Some sequences in the Bellsund area show cross-bedding which suggests input from the eastern margin of the basin. At Kopernikusfjellet, the thin, entirely conglomeratic sequence is interpreted as forming on top of the Hornsund High. The carbonates clearly indicate open shallow marine conditions, while the terrigenous elastics were probably deposited in a nearshore, paralic environment. Some beds may represent partly reworked fluvio-deltaic sediments. As the dolostones contain abundant corals in the middle unit, the dolomitisation was probably early diagenetic, following the regressive phase after the deposition of the carbonate, which may have created restricted lagoonal environments in the nearshore area, with deposition of sulphates before the advance of terrigenous deposits (Nysaether 1977). Northwards there is a progressive decrease in elastics with a transition to the Tyrrellfjellet Mbr. The conglomerates may be littoral.

Kapp Dun6r Formation (Bjornoya).

Consisting mainly of dolostones and fusulinid-rich limestones, sequences of the Kapp Duner Formation reach 75 m. The formation was deposited during a time of stabilisation and postrift subsidence, following Carboniferous tectonic activity. This resulted in the establishment of a marine shelf, containing open to restricted environments, allowing the deposition of carbonates characterized by bioherms, biostromes and patch reefs (Agdestein 1980). Several karst surfaces indicate periods of sub-aerial exposure which probably resulted from small fluctuations in sealevel. The dominantly dolomitic nature of the carbonates suggests deposition under conditions of high salinity for much of the formation. Folk & Siedlecka (1974) distinguished petrographic characteristics, such as very finely crystalline penecontemporaneous dolomite and replaced sulphate nodules with a fibrous texture, authigenic length-slow chalcedony and sulphate inclusions, which they interpreted as being indicative of a

CARBONIFEROUS A N D P E R M I A N HISTORY OF SVALBARD hypersaline evaporitic environment. Other petrographic evidence suggests the presence of fresh water during cementation and the diagenetic history of the lower part of the formation supports evidence of the schizohaline environments of fluctuating salinity as presented by Siedlecka (1972, 1975), Folk & Siedleck (1974) and Adgestein (1980). This may have developed by the periodic flooding of an evaporitic lagoon or sabkha by rain, or by diagenesis within a zone of fresh connate water. The occurrence of evaporites and length-slow chalcedony (typical of evaporite environments) indicates a hot dry climate and partial sub-aerial exposure. However, the palaeoaplysinid build-ups and the rich fossil content of many of the carbonate rocks indicate that normal marine conditions with shallow-water carbonate deposition was prevalent for some of the time, and that some of the dolomitisation, at least, is secondary. These reefoid structures have a markedly lenticular form, with long axes parallel to the temporary quiescent NE-SW-trending fault lineaments on Bjornoya which can be compared with the relationship of similar build-ups to the Billefjorden Fault, seen in the Tyrrellfjellet Member of central Spitsbergen (Aga et al. 1986). Faulting, flexuring and erosion followed, to produce a gentle anticlinal structure. This occurred contemporaneously with Early Permian regression and deposition of dolomites and sabkha evaporites elsewhere in Svalbard (Aga et al. 1986).

17.5.4

Sakmarian-Artinskian deposition (upper Gipsdalen Group)

C o a s t a l c a r b o n a t e s , e v a p o r i t e s a n d m i n o r s a n d s t o n e s are typical o f this interval in S p i t s b e r g e n a n d N o r d a u s t l a n d e t . In B j o r n o y a shallow m a r i n e limestones follow s a n d s t o n e s , transgressive o n e r o d e d limestones o f the u n d e r l y i n g K a p p D u n t r F o r m a t i o n .

Dickson Land Subgroup Gipshuken Formation (throughout Spitsbergen Basin and eastwards into Nordaustlandet). Present across much of western and central Spitsbergen, the Gipshuken Formation is 150-250 m thick, consisting mainly of carbonates and evaporites with minor quantities of sandstone. North of Isfjorden, in the Dicksonfjorden and Billefjorden area, stacked sabkha cycles occur, described by Holliday (1966, 1967, 1968a, b) and Lauritzen (1981). They suggested a coastal environment that was maintained for a considerable time with alternations of regressive periods of evaporite formation and periods of intertidal deposition, which allowed the deposition of a substantial thickness of evaporite-dominated sediments. It is evident from the succession that marine flooding took place, probably as a result of storms and relative sealevel changes, causing erosive surfaces, ripples, cross-bedding and oolites which are all indicative of stronger currents, and may represent tidal channels in the lagoon. The nodules and interbeds of evaporites which occur in the dolostones of the upper part in the Dicksonfjorden area, although not dominant, are considered by Lauritzen to represent shorter sabkha events in a more marine-influenced environment. Even though dolomitization is extensive throughout the succession, widespread algal lamination can still be seen, showing algae to be an important constituent of the dolomicrite. Early diagenetic dolomitization is characteristic of supratidal coastal sabkhas (Kinsman 1969). Once shoreline regression occurs, evaporitic minerals are deposited in the upper part of the marine wedge and dolomitization of the finegrained carbonate sediment takes place. In this process, calcium ions are released, causing the precipitation of more gypsum or anhydrite. The dolomicrite lithology suggests deposition mainly in lagoons, but more open marine carbonates with corals are also found. Grain-supported carbonates reflect deposition in agitated environments such as channels or areas bordering the lagoons. Replaced aragonite needles suggest lower intertidal or submarine cement (Lauritzen 1981). The cyclic, algal-laminated sediments seen in Nordaustlandet are also interpreted as representing a lagoonal environment, with the intraformational conglomerate beds representing tidal channel infills within this environment (Lauritzen 1981). These lagoonal environments pass upwards and laterally into a more open marine shelf carbonate zone, perhaps reflecting a marine transgression. Lauritzen (1981) discussed the origin of the sulphates and considered that at least some of them may have a diagenetic origin as sulphate crystals have commonly been observed growing at the cost of dolomite, though also vice versa. Gypsum is replaced by anhydrite at depth and was probably originally deposited as anhydrite (as there is no deformation of the host rock, which would occur on dehydration of gypsum) with its origin in brines produced by evaporation of sea water or ground water. Lauritzen concluded that the evaporites could have originated in three ways:

323

(i)

primary precipitation from standing water (probably the case in the laminated and bedded anhydrites); (ii) precipitation within the vadose zone, which produces the chicken-wire structure found in the regular beds; (iii) as a later stage diagenetic product formed by solution of pre-existing rocks; (the Kloten Breccia may have provided a source, see below); the infilling of cracks, fissures and stylolites may be the result of such diagenetic mineralization. Arenaceous facies, which appear locally in northern Torell Land, probably indicate proximity to the Hornsund High. Brecciation may have occurred as a result of solution of evaporites interbedded with the dolomites, followed by collapse. The cellular type of breccia may have been formed by solution and the volume change on hydration of anhydrite, which does occur as interbeds in the lower twothirds of the formation. The brecciated sequences in western areas occur in close association with sabkhas and are thought to represent early to mesogenetic solution and collapse phenomena. At other localities, especially in thick sequences along the Billefjorden Fault Zone and in thinner, but characteristic, beds in eastern Svalbard, they may represent primary depositional features. Possible origins include downslope movement following early lithification on organic build-ups to form brecciated flank facies and/or debris flows associated with minor movements on lineaments. The Zeipelodden Member seems to represent intertidal to supratidal environments, characterized by the growth of algal crusts and mounds (Lauritzen 1981). The mixture of white chert and calcite found within is interpreted as remnants of sulphates representing periods of deposition of evaporites that were partly dissolved during periods of flooding, and which resulted in the formation of solution breccias. The pattern of dolomitization in the massive breccias indicates that some dolomite was present before brecciation and that dolomitization continued after brecciation. Before brecciation, these rocks probably consisted of unlithified, partially dolomitized limestone, but the presence of primary dolomite cannot be ruled out. Karstification was reported from Mathiesondalen by Salvigsen, Lauritzen & Mangerud (1983).

Hambergfjellet Formation (Bjornoya). As in the Miseryfjellet Formation, this unit is dominated by limestone except for sandstones at the base. The unit is approximately 100m thick. This thin, easterly onlapping clasticcarbonate wedge covered part of the now peneplaned anticlinal structure formed after the deposition of the Kapp Dun+r Formation. The arenaceous deposits at the base of the formation are typical of a marine transgression following a period of erosion. Periods of emergence are indicated by the root horizons, calcretes and karst surfaces. The overlying carbonates indicate a shallow-marine environment. This probably resulted from the same rise in sea level which produced the open marine carbonates at the top of the Gipshuken Formation in southern areas of Spitsbergen, east of the Hornsund High. Terrestrial influence is smallest at the top of the formation.

17.5.5

Kungurian-Guadelupian deposition (Tempeffjorden Group)

The Tempelfjorden Group clastics a n d c a r b o n a t e s .

is characterized by s h a l l o w - m a r i n e

Kapp Starostin Formation (throughout Spitsbergen except Sorkapp Land). The Kapp Starostin Formation is the main unit of the Tempelfjorden Group. The type section is at Kapp Starostin (Festningen), Nordenski61d Land, where the formation is up to 412m thick. The formation rests disconformably on carbonates, evaporites and siliciclastics of the Gipsdalen Group and is unconformably or disconformably overlain by the Vardebukta Formation of the Triassic Sassendalen Group. It comprises three principal members. The (basal) Voringen Member is a coarse, sandy bioclastic limestone. The (middle) Svenskeegga Member is a complex facies mosaic of mudstone, chert, glauconitic sandstone, silicified limestone and limestone. The (upper) Hovtinden Member includes mudstone, chert and glauconitic sandstone. Current investigation by CASP (D. I. M. Macdonald pers. comm.) postulates five major facies associations: (i) basal karst and associated facies; (ii) basal limestone facies association; (iii) black shale facies association; (iv) spiculite facies association; (v) sponge-bryozoan facies association. As this study is in progress and publication is not imminent, the following descriptions are based on available literature and checked for consistency by D. i. M. Macdonald. Ezaki, Kawamura & Nakamura (1991) made a detailed study of facies and

324

CHAPTER 17

fauna of the succession at Festningen, especially with regard to changing water depths and transgressive-regressive cycles. The formation was deposited in a broadly trangressive setting, although there are reversals of this trend. Nearshore to shallow-water marine facies characteristic of the base are replaced upwards by open marine facies, with a shift of sedimentary environments southwestwards with time as the Hornsund High became partly submerged due to deposition of the Hovtinden Member (Nysaether 1977). Glauconite is a distinctive constituent of the formation, except for the Voringen Member, and was found by Siedlecka (1970) in almost all the thinsections she examined, generally less than 3% in the mode, but occasionally up to 25 %. Much of this occurs as grains which could have been redeposited (some patchy distribution of quartz and glauconite grains suggests local accumulations), but some is undoubtedly authigenic (e.g. infilling sponge spicules) and the conditions of sedimentation must have been suitable for the formation of this mineral, which has the following specific requirements (Cloud 1955): marine environment of normal salinity; slightly reducing conditions (perhaps due to the decay of organic matter present); water temperature averaging 14-15~ rather slow sedimentation, in a depth of between 15 and 500m. The origin of the silica is probably the dissolution of sponge spicules, remnants of which are seen to be abundant in some thin sections, commonly forming up to 75% of the rock matrix (Nysaether 1977). It was precipitated in pore spaces except in those limestones which were cemented early on by calcite. The chert bands and nodules which occur in the fossiliferous biosparites are of diagenetic origin, while the massive chert interbedded with the shales represents deposition in a more basinal environment and has been regarded as the product of primary silica precipitation under semi-stagnant, slightly reducing conditions (Siedlecka 1970). However, much of the massive chert is calcareous, so may be diagenetic, replacing carbonate. The distribution of siliceous and calcareous sponges has been used in Permian basins of the USA as a bathymetric indicator (Worsley in Aga et al. 1986); siliceous sponges suggest water depths in excess of 200m. The abundance of these sponges indicates relatively cool, deep shelf environments. The massive chert bodies are interpreted as being sponge build-ups (Steel & Worsley, 1984). There are two facies associations (dominated by shale and chert) in the Hovtinden Member: (i) shale with sponges also corals, crinoids and bryozoans; (ii) shale and sandstone with Zoophycos and rare glauconite in the sandy beds (D. I. M. Macdonald pers. comm.). The Zoophycos was noted by Worsley (Aga et al. 1986) and the thin-shelled brachiopods and well-preserved sponges (Hurcewitz, 1982) indicate relatively quiet water, offshore, well below normal wave base, with low rates of sedimentation. An abundance of skeletal debris, some in life-position and burrows that penetrate the glauconitic sand, point to oxidizing conditions during deposition, though slightly reducing conditions, probably associated with organic matter, must have existed, perhaps just below the surface, for the glauconite to form. It was thus a deeper-water shelf facies which prevailed in the central part of the basin. However, the occurrence of thick, crossbedded, sandy units within the 'basinal' facies suggests shallower water. The Svenskeega Member breccia points to a local palaeoslope in the Tempelfjorden area which allowed a gravity slide to occur, possibly at the boundary between shallow and deeper water facies, and also to early silica diagenesis. The carbonate facies represents well-oxygenated water on shallower parts of the shelf. There is an abundance of large, broken fossil fragments which must have been redeposited locally, perhaps from attempts at early build-ups (Siedlecka 1970 referred to patch reefs). Shallow-marine conditions were widespread during deposition of the Voringen Member in Kungurian time. The bioclastic arenaceous facies is interpreted as representing a sublittoral shelf environment with terrigenous sediments, influenced by strong wave action and bottom currents. The sands represent shallow migrating shoals and banks. Benthic fossil fragments are generally large and angular, so have not been transported far. The sandstones of the northwest reflect relatively low rates of deposition in intermediate water depths. The southwestern basin margin shows a major upward-coarsening silt to sandstone sequence which thins rapidly westwards onto the Hornsund High. In the Hornsund region, a very thin sequence of open-marine and intermediate shallow-water siltstone facies is underlain by the transgressive basal conglomerates which lie on different units of the Treskelodden Formation, infilling karst surfaces in the limestones. At Austjokeltinden, the repeated occurrence of conglomerates and lag deposits of abraded phosphatic nodules suggest an extremely condensed sequence with a complex history of burial, exhumation and reworking of fossil shells. Other sections, although

only a few metres thick, contain fine-grained limestones with textures and ichnofossils that suggest deposition in low-energy environments. This area would thus seem to be near the eastern margin of the Hornsund High which seems to have been emergent until the Triassic Dienerian stage (Hellem & Worsley 1978), though facies patterns in adjacent areas may indicate that it was submerged in the transgression at the base of the Templefjorden Group then subsequently uplifted again (Worsley in Aga et al. 1986). Thus, shallow-marine conditions extended across the basin with deposition of transgressive deposits at first in Kungurian time, before a general deepening in the Isfjorden Basin, when the marginal facies became restricted to the north and south, nearer the land areas of the Northern Block and the Hornsund High. A regression led to the encroachment of glauconitic sandstone during the Ufimian stage, especially from the northwest, and latest Permian time is marked by an apparent hiatus, with the absence of identifiable Wordian, Capitanian or Lopingian strata, due either to marine regression or non-deposition. Across much of Spitsbergen, basal Triassic strata overlie Permian rocks without apparent unconformity, although there is a sharp change in lithology. No conglomerates are found in basal Triassic rocks, except in southern Spitsbergen, where there is a strong unconformity on the Hornsund High, indicating continued uplift of this area. Gruszczynski & Malkowski (1987) reported stable isotope records of the Kapp Starostin Formation which was discussed by Malkowski, Gruszczynski & Hoffman (1991). However, Mt~, Grossman & Yancey (1997) questioned part of their result as 'diagenetic artifacts' but concluded that a Kazanian-Tatarian 613C maximum of 7.5% is substantiated and represents the highest specified Phanerozoic values and probably correlates with a similar maximum in East Greenland and in northwestern Europe. The shift was thought to reflect global storage of organic carbon by Late Permian coal volume changes.

Tokrossoya Formation (Sorkapp Land).

In southwestern Sorkapp Land this formation replaces the Kapp Starostin Formation, with which it has many similarities. It is at least 400 m thick. In western Sorkapp Land there is a thick upward-coarsening sequence. Although the base is not exposed, spiculitic shales and siltstones grade upwards into sandstones interpeted as shallow-marine sand wave deposits (Worsley in Aga et al. 1986). The coarser units seem to thin southwestwards away from the Hornsund High. However, these exposures are highly tectonized and may not be in their original position in relation to the High. A fault separates them from the rest of the Permian outcrop. The Upper Member represents a shallowmarine marginal environment which points to the existence of land nearby whereas the Lower Member represents deeper, quieter basinal conditions. The facies are the same as those found further north, but there has been an increase in thickness in this area, possibly accommodated by a Late Permian fault bounding the Hornsund High to the northeast.

Miseryfjeilet Formation (Bjornoya). This formation is l15m at its type section, where it consists almost entirely of limestone except for sandstones at the base. It is evident that a mid-Permian transgression covered an uplifted and peneplaned surface, submerged after the cessation of earlier tectonic activity, but still a positive structure (Hellem 1987). The sedimentary environment of the unit has been discussed in detail by Siedlecka (1975) and Hellem (1987). In general, the arenaceous biosparites indicate a high energy basin margin environment under shallow marine conditions of lower shoreface and offshore shelf above wave base. The basal arenaceous strata are transgressive littoral and barrier deposits, and Siedlecka has inferred from the bimodality of some of these sands that they are reworked aeolian sands. The latter may have been reworked and incorporated, along with bioclastic debris into the carbonate sands of the shelf. The cross-bedded sandstone body on Miseryfjellet may be an offshore sandbank with cross-bedding directed shorewards i.e. to the southeast (Worsley & Edwards 1976). Hellem (1987) considered it to be a regressive sequence, representing shoreface and foreshore deposits. The formation may represent a southern marginal facies of an extension of the Spitsbergen Basin, beyond the Hornsund High, referred to as the Bjornoya Basin, where the rocks are in marked contrast to the spiculitic cherts which dominate the Templefjorden Group of the Spitsbergen Basin.

17.6

Carboniferous and Permian fossil record

T h e variety o f facies in S v a l b a r d at different times t h r o u g h this interval o f nearly 120 million years precludes a full r e c o r d o f t h e progress o f life. Nevertheless the fossil r e c o r d is rich as is e v i d e n t

CARBONIFEROUS AND PERMIAN HISTORY OF SVALBARD

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326

CHAPTER 17

from the selection of palaeontological studies noted in Fig. 17.6. Until recently, the conspicuous macrofossils and the routine micropalaeontological investigations have consumed resources to the exclusion of knowledge of other elements in the global biota, or perhaps the environments for life and preservation have in each case been sufficiently extreme for the fossil record to give a limited picture of life at that time and place. For example little, if anything, has been recorded concerning microbial life. Lacking distal marine shaly facies there is little record of vertebrates, ammonoids or other cephalopods. Trace fossils are rare except in some bioturbated Kapp Starostin facies (Zoophycos was mentioned by Worsley in Aga et al. 1986). Figure 17.6 gives an indication of the range of fossils recorded.

17.6.1

Plant life

After late Devonian colonization of continental environments by primitive land plants, Carboniferous vegetation quickly achieved a rich diversification. Svalbard records are limited to the deltaic environments of the Tournaisian through Serpukhovian epochs; but Svalbard has the advantage of preserving earliest Carboniferous floras following directly on latest Devonian, whereas in many parts of the world the typical 'coal measure' environments came later.

Maerofloras. The macroflora as described by Nathorst in several papers (e.g. 1900) is dominated by pteridophytes, with Equisetales, notably Calamites pith casts, and many arborescent lycopod genera including several species of Lepidodendron, also Bothrodendron, Cyclostigma, Lepidophloios, Archaeosigillaria, Sigiilaria and Stigmaria. There is a similar diversification of pteridosperms with fern-like fronds of Sphenopteridium, Sphenopteris, Cardiopteridium and several other genera. Seward (1931) pointed out that the Early Carboniferous foras (of which the Svalbard record was certainly the best known) has affinities in the southern hemisphere. This contrasts markedly with the widespread records of Late Carboniferous and Permian floras in which there is a reduction in the diversity of species coupled with a Tethyan barrier between the northern (Laurasian) flora and the distinct Glossopteris flora of Gondwana. Of these events Svalbard tells us little. Nathorst (1920) described three separate floras from the Orustdalen Formation of Bellsund (Billefjorden Group) Forbes, Harland & Hughes (1958), on the basis of correlation with Dinantian floras of Scotland (e.g. Cyclostigma and Lepidophloios scoticus) concluded that the Billefjorden Group spanned much of Russian Early Carboniferous time and did not correlate with the immediately preceding Devonian flora of Bjornoya. They noted the absence of the supposedly Devonian 'Ursa Flora' of Bjornoya, and the presence of some forms not known below earliest Namurian time elsewhere, such as Stigmaria rugulosa. This 'Ursa Flora' has been shown by Kaiser's work on spores (1970, 1971) to span the Devonian-Carboniferous boundary and on the basis of lycophyte species present, a floral break has been recognized by Schweitzer (1967, 1969) between the Vesalstranda Member and the Tunheim Member. The Vesalstranda Member alone contains ?Cyclostigma brevifolium and Sublepidodendron isachensii. Pseudolepidendropsis carneggianum is exclusive to the Tunheim Member. Cyclostigma kiltorkense occurs in the upper Vesalstranda Member and also in the Tunheim Member.

Microfloras. Inevitably the reproduction of the macroflora resulted in rich palynological material so that some Billefjorden Group rocks have proved productive. (a) Palynomorphs. Hughes & Playford (1961) and Playford (1962, 1963) recognized two distinct palynomorph assemblages defining the rarituberculatus and aurita zones. (i) The index species of the rarituberculatus assemblage, Lophozonotriletes rarituberculatus and others are characteristic of

Tournaisian strata in Russia. Playford quoted sixteen species which do not occur before the Tournaisian, and hence concluded an exclusively Tournaisian age for the assemblage. However, publication of Van Veen's evidence for a Late Famennian age of the lower H6rbyebreen Formation in Central Spitsbergen is awaited. (ii) The aurita assemblage is marked by a complete absence of specifically Tournaisian forms. It conforms closely with microfloras reported from Visean strata of the Russia, and in some respects can be correlated with the Lower-Middle Chesterian stage of Canada. Some Serpukhovian (Namurian) forms appear towards the top of the zone, and Playford concluded that the assemblage has a Visean age, possibly extending to Early Serpukhovian. (b) Spores. Bharadway & Venkatachala (1961) and Dettmann & Playford (1963) described spore assemblages from the Mississippian of Spitsbergen. Four spore assemblages have been recognized in the terrestrial Roedvika and Nordkapp Formations of Bjornoya as a result of the work of Kaiser (1970, 1971), which have proved more useful than the macroflora. A distinctive, purely Devonian, assemblage in the Vesalstranda and lower Kapp Levin members is of Late Famennian age and can be further subdivided into three, with microflora closely related to the Prolobites zone of the Russia. The second earliest Tournaisian assemblage is from the lower Tunheim Member and occurs with the 'Ursa' macro-flora described above. A Late Tournaisian assemblage occurs higher in the Tunheim Member and a Late Visean assemblage is found in the Nordkapp Formation. From less promising Permian strata Mangerud & Konieczny (1993) recognized three assemblages of palynomorphs. (1) Vittalina assemblage: latest Noginskian to mid-Asselian (2) Hammiapollenites tractiferinus assemblage: mid-Asselian to mid-Artinskian and (3) Kraeuselisporites assemblage: mid-Artinskian to ?earliest Longtanian. (c) Algae etc. Carbonate environments favoured calcareous algae. Within the Permian strata are reefs of Palaeoaplysina. They became interesting to industry because of their reefoid shape and porosity (Skaug et al. 1982). Palaeoaplysina is commonly regarded as a calcareous hydrozoan.

17.6.2

Foraminifers

Large foraminifers are easy to collect in the field and are valuable as age indicators, though correlation is difficult, because as bottom dwelling creatures they tend to be provincial. Of the potential international Pennsylvanian and Permian correlation, only Bashkirian to Early Sakmarian forms have been found in Svalbard. A zonal scheme for Svalbard was initiated by Forbes (Forbes et al. 1958) and worked out and applied by Cutbill (Cutbill & Challinor 1965). This work led to the recognition of seven fusulinid zones, five of which are Carboniferous, which were based on a very wide sampling of the group and have proved valuable for internal and external correlation. Some detail of these Carboniferous zones is given below (oldest to youngest). (1) Antiqua Zone. This zone occurs only in the upper part of the Ebbadalen Formation, where the distinctive assemblage includes Pseudostaffella antiqua and Pseudoendothyra spp. with Millerella, Eostaffella, Ozawainella and Profusulinella species occurring less commonly. Fusiform species are rare or absent. P. antiqua ranges from Namurian B to the Moscovian Vereiskiy horizon, but as fusiform species are abundant in the latter horizon, the zone probably correlates with the Bashkirian Stage. (2) Profusulinella Zone. An assemblage comprising Profusulinella prisca. P. cf. librovitchi. Waeringella eopulchra, Ozwainella mosquensis, Pseudostaffella antiqua, and P. sphaeroidea with Eostaffella, Pseudoenthyra and Eofusulina species is found in the lower Minkinfjellet and Scheteligfjellet formations. The fauna is very similar to that of the Moscovian Vereiskiy and Kashirskiy horizons. (3) WedekindeUina Zone. This zone contains a wide variety of genera, of which the typical species include Pseudostaffella

CARBONIFEROUS AND PERMIAN HISTORY OF SVALBARD

sphaeroidea., Waeringeila eopulchra, Ozawainella mosquensis, Beedeina rockymontana, Wedekindellina dutkevichi and Fusulinella boeki plus rare Quasifusulina and Schubertella species. The last three species suggest a correlation with the Moscovian Podol'skiy and Myachkovskiy horizons. This fauna is found in the upper part of the Minkinfjellet and Scheteligfjellet formations. The species Fusiella typica, Fusulina pankouensis and Waeringella usvae occur in the Jotunfonna Beds of the Kapitol Member and suggest a definite correlation with the Myachkovskiy horizon. (4) Waeringella usvae Zone. This zone is confined (by definition) to the Gerritbreen Beds. The lower part of these beds contains abundant Protriticites oratus, Waeringella usvae and Montiparus montiparus, and also Fusulina sp. The assemblage, plus Ozawaiconella, Quasifusulina and Schubertella species, indicates a correlation with the Kasimovian stage. Higher up, Montiparus unbonoplicarus, M. Paramontiparus, Tricetes rossicus and Tricetes sp. are found, which are more characteristic of the Klazminskiy horizon. Thus, the zone correlates with the Kasimovian and Gzelian stages and may be subdivisible. (5) Rugofusulina arctica Zone. The Mathewbreen Beds of the Billefjorden area are dominated by the species Rugofusulina arctica with rare Quasifusulina longissima and Schwagerina and Waeringella species. The fauna contrasts with the usvae zone beneath in being distinctly more advanced, and is correlated with the latest Carboniferous Noginskiy horizon of the Moscow Basin (formerly Orenburgian), which is now included in the top of the Gzelian stage. (6) Schwagerina anderssoni Zone. This zone, with only abundant S. andersonni, some Rugofusulinas and rare Pseudoschwagerina, was correlated with Asselian (and Early Wolfcampian). (7) Monodiexodina Zone. This has only Schwagerina in addition and is correlated with that Late Wolfcampian (Early Sakmarian) zone. The larger forams do not persist above the Tyrrelljellet Formation into the more saline Gipshuken Formation and they are thus limited to the Wordiekammen, Minkinfjellet and Ebbadalen formations. Solov'yeva (1969) described the genera Wedekindellina. Small foraminifers have received less study and are less reliable indicators of stratigraphic level. However, Soviet workers have recognized a total of twelve assemblages in Spitsbergen's Carboniferous and Permian rocks (Sosipatrova 1967). The seven Carboniferous assemblages, while not referred to any type sections do, however, confirm Cutbill's correlation with the Russian Platform. On the other hand her Permian zones extend beyond the range of the larger forams and provide an independent estimate of the age, especially of the Tempelfjorden Group, which she correlated with Russian stages. Her three latest zones correspond with the three members of the Kapp Starostin Formation thus: Hovtinden Member Frondicularia bajcurica (Early Ufmian) Svenskeegga Member Gerbelna komiensis (Late Kungurian) Voringen Member Nodosaria Longa (Early KungurianLate Artinskian). If reliable, these correlations would establish the late Permian hiatus in Svalbard as corresponding to most of the Zechstein subPeriod. Igo & Okimura (1992) made a further study of the Carboniferous-Permian foraminiferal succession. 17.6.3

Corals

Rugose corals are sufficiently conspicuous for the name 'Cyathophyllum Limestones' (Cyathophyllum Kalk of Nathorst 1910) as was used for the Tyrrellfjellet Member. Study of the coral faunas of Svalbard, possibly begun by Heritsch (1939), has indicated that this group of fossils may prove to be increasingly useful stratigraphically in the Arctic (Fedorowski 1964, 1967, 1975). However, at the present time, age correlations based on the coral assemblages must be considered as corroborative evidence only. Fedorowski concluded that both Carboniferous and

327

Permian faunas migrated to Svalbard and to the Canadian Arctic from the FSU to the southeast, where they evolved. A further study was reported by Ezaki & Kawamura (1992). Stromataporoids, of uncertain biological affinity, had the capacity to build reefs which are evident in the 'hydrozoan buildups' in early Permian strata on the Nordfjorden High and to the east (Worsley in Aga et al. 1986, p. 53).

17.6.4

Brachiopods

Brachiopods are amongst the most abundant and easy to collect of all Svalbard macrofossils and have been monographed by Wiman (1914), Stepanov (1936, 1937) and by Gobbett (1963) who reviewed the previous work and examined extensive international collections to describe 143 species of which 19 were new and many others have been recorded only in Svalbard. However, many appear to have long ranges so their correlation potential is limited. The following list gives an impression of the faunal composition. Atremata 2 spp.; Neotremata 2 spp.; Dalmanelloidea 2 spp.; Strophomenoidea 8 spp.; Productoidea 59 spp.; Chonetoidea 7 spp.; Rhynchonelloidea 10 spp.; Spiriferoidea 47 spp.; Terebretuloidea 6 spp.; of doubtful occurrence or uncertain systematic position 8 spp. Further studies have been reported by Nakamura, Kimura & Winsnes (1987) and Malkowski (1988). Most collections have come from the Spirifer Limestone and Brachiopod Chert (Kapp Starostin Formation) and this particularly rich brachiopod fauna is the most difficult to correlate. It was given the stage name Svalbardian by Stepanov (1957). Gobbett found this useful if only to label its unknown age. This uppermost Permian Formation has been characterized by its lithology and fossil content (Table 17.1) There is indeed a variety of facies within this group ranging from quiet marine with bioturbation to high-energy environments with robust spirifers. The productid beds are somewhat intermediate. Somewhat similar difficulties pertain in the Russian Arctic successions both east and west of the Urals; and Ustritskiy (1983) proposed a Permian faunal sequence: Sezymian (approximately Asselian and Sakmarian); Artinskian; Paykhoyian (approximately Kazanian and Ufimian) and Novazemlian (approximately Kazanian or Guadelupian). It is this latest that has most Svalbardian affinity. Below the Kapp Starostin Formation Gobbett distinguished two distinct brachiopod faunas within the Gipsdalen Group. The later one was in the Permian, Tyrrellfjellet Member of Btinsow Land and the Cora limestone of Bjornoya (Hambergfjellet Formation) and the fauna was consistent with the Sakmarian age concluded on the basis of fusulines. The earlier fauna was from the Minkinfjellet (Campbellryggen Subgroup), Scheteligfjellet, T~rnkanten and Kapp Khre (Ambigua Limestone) formations and is consistent with a BashkirianMoscovian age by correlation with the Moscow Basin.

17.6.5

Bryozoans

Lazutkina & Goryunova (1972) compared bryozoans of Spitsbergen and the Russia. From well-preserved silicified material in the Kapp Starostin Formation Nakrem & Spjeldn~es (1995) redescribed

Table 17.1. Subdivisions of the Kapp Starostin Fm Nathorst (1910)

Gee et al. (1952)

Cutbill & Challinor (1965)

Productus Ffihrende Kieselgesteine Spiriferenkalk

Brachiopod cherts-upper Brachiopod cherts-middle Brachiopod cherts-lower

Hovtinden Mbr SvenskeeggaMbr Voringen Mbr

328

CHAPTER 17

Toula's (1875) Spitsbergen Ramipora hochstetteri and reviewed the literature, especially from Permian Svalbard rocks, revising the taxonomy in some earlier records and concluding extensive synonymy. Nakrem (1994) monographed 41 species from the Voringen Member and concluded an Artinskian-Kungurian age, by correlation with the Sverdrup, Wandel Sea and Timan-Pechora basins.

17.6.6

Gastropods

Yochelson (1966) reported new Permian gastropods from Spitsbergen and Alaska.

17.6.7

Trilobites

Osmolska (1968) reported two new trilobites from the Treskelodden Formation of Hornsund and Kobayaski (1987) described a Permian trilobite from Spitsbergen.

17.7

northward motion of Laurasia through the global climatic zones. The most recent palaeomagnetic data shows that the palaeolatitude of Svalbard was between 14~ and 18~ N during the deposition of the Early Carboniferous Billefjorden Group (Watts 1985), while it was 35.5 ~ N in Late Paleozoic time (Vincenz & Jelenska 1985). Harland, Pickton & Wright (1976) had estimated a Carboniferous through Permian latitude from 15-25 ~ to 45 ~.

Carboniferous-Permian tectonic control of sedimentation

The Early Carboniferous succession is characterized by deposition in rather humid climates, with a high water-table resulting in reducing conditions and the development of coal and clayironstone horizons. In contrast, in latest Serpukhovian (Namurian), Bashkirian and Moscovian times, there were arid or semi-arid conditions. Finally Permian climates appear to have been humid and temperate. Lateral variations in Carboniferous stratigraphy are shown in a fence diagram (Fig. 17.7), from work by Cutbill & Challinor (1965). The cause of the climatic change, which has been recognized throughout Svalbard at this time, may have been the gradual

17.7.1

Tournaisian-Visean-Serpukhovian (Mississippian) events

This Tournaisian-Serpukhovian phase (Fig. 17.8) was characterized by fault-controlled terrestrial sedimentation of the Billefjorden Group, with the formation of thick continental sandstones, shales and coals; there was significant tectonic control at this time. The strata are of limited lateral extent, mostly deposited in elongate basins containing poorly drained floodplains, with lakes and swamps accumulating sediment brought by rivers draining a vegetated landscape. Tournaisian basal braided river conglomerates in the Horbyebreen Formation of Dickson Land were deposited from a horst area to the east of Ny Friesland. Hutchins (1962) found few metamorphic heavy minerals in these sediments so that the source could not have been western Ny Friesland, but to the east of Veteranen Line where the Veteranen Group (Precambrian) sediments are rich in quartz (contra Aga et al. 1986). They pass up into the finer coaly floodplain deposits of a northwardflowing meandering river. The periodic flooding may have been caused by tectonic downthrow (Gjelberg & Steel 1979). The Tournaisian member of the H6rbyebreen Formation tended to follow the pattern of Old Red Sandstone sedimentation with northward flowing streams as did the Adriabukta Formation in the south. By Visean time, similar environments were established in central Spitsbergen resulting in the fluviatile-deltaic deposits of the

Fig. 17.7. Fence diagram illustrating lateral variations and tectonic controls on the Carboniferous stratigraphy (redesigned by I. Geddes, using concept of Cutbill & Challinor 1965, but with contemporary nomenclature).

CARBONIFEROUS AND PERMIAN HISTORY OF SVALBARD

329

Fig. 17.8. Early Carboniferous lithofacies maps. (a) Famennian-Early Tournaisian, (b) Late Tournaisian-Visean, (c) effect of block-faulting on deposition of the Billefjorden Group in central Spitsbergen.

330

CHAPTER 17

Orustdalen Formation (Fairchild 1982). Meanwhile, in the Inner Hornsund Trough, there was a Tournaisian-Early Visean marine basin, if somewhat restricted, where clastics and shales of the Adriabukta Formation, which appears also to have had a source to the east, were being deposited. Further south, post-Svalbardian sedimentation had already begun in the Bjornoya Basin in Late Famennian time with the poorly drained floodplain deposits of the Roedvika Formation, from a southerly source. Its lowest (Vesalstranda) member consists largely of floodplain sediments deposited by northwestwardflowing meandering streams. The overlying and coarser Kapp Levin Member was deposited by east or northeastward-flowing braided streams. The uppermost Tunheim Member represents a return to meandering river conditions from the south or southeast which persisted throughout the Nordkapp Formation, with a return to eastward-flowing sandy braided streams. Alluvial fanglomerates in the upper part, may mark renewed uplift on the West Bjornoya Fault. This probable extension of the PalaeoHornsund Fault was reactivated intermittently during the Carboniferous Period, e.g. in the Landnordingsvika Formation above, with its similar alluvial fan deposits and which built out eastwards onto an alluvial plain. There was no marine influence until Late Bashkirian-Moscovian time. Marine conditions did not persist in the Inner Hornsund Trough, and alluvial fans and floodplain deposits spread into it, followed by the braided stream deposits of the Hornsundneset Formation and the fluvial sandstones and floodplain shales and coals of the Sergeijevfjellet Formation. They had a western source and covered a much wider area than the underlying Adriabukta Formation, which was probably restricted to a fault-bounded trough. Further north at this time, the Vegardfjella Formation's floodplain deposits continued the continental succession of western Spitsbergen, which may have been continuous eastwards with the similar Mumien Formation of the Billefjorden Trough. Like the laterally equivalent Sergeijevfjellet and Hornsundneset formations further south, the Mumien Formation covered a greater area than the fault-bounded Horbyebreen Formation below (Fig. 17.8). Thus, Visean alluvial fan sediments spread over a wider area. Dominance of a westerly rather than easterly source indicated increased tectonic activity along the western boundary faults. The first signs of uplift of the Nordfjorden Block were in Vis~an time. Large fan systems show 1.5km of braided stream sandstone sequences in the southwest and northwest basins of Spitsbergen. This may reflect major downwarping along the Palaeo-Hornsund Lineament as these clastic wedges thin eastwards (Aga et al. 1986). The Mumien Formation developed in a subsiding trough east of the Billefjorden Fault Zone. The Orustdalen, Vegardfjella and Hornsundneset formations occupied basins immediately to the west of the Kongsfjorden-Hansbreen Fault Zone (KHFZ). These two fault zones, originally separating the eastern, central and western terranes, thus continued to be active but with no demonstrable strike-slip. The isopach patterns of the Vegard and Orustdalen formations parallel almost exactly the KHFZ. They were drawn in ignorance of this hypothesis. Decreased subsidence rates by the end of Vis6an time are suggested by a widespread retreat of the braided fans and their replacement, in many areas, by fine-grained marsh and floodplain environments. Red beds first appeared at the top of the Vegardfjella Formation, a precursor of the red beds common in Bashkirian & Moscovian formations and indicative of a Serpukhovian/Early Bashkirian change from humid to arid conditions. This coincided with a regional rise in sea level bringing a transition from continental to marine sedimentation, that persisted into Early Permian time. The humid climatic facies of this alluvial fan and swamp/ floodbasin association show the following features which contrast with the more arid Bashkirian-Moscovian fan and playa/sabkha association. The mineralogy is more mature, with a dominance of quartz and quartzite, as is texture, with a smaller average grain size, more sorting and less clay matrix. This is because braided stream facies dominated the humid environments in contrast to the massflow and stream-flood facies prominent in the arid environments.

The subaqueous fans actually show little difference in the two associations. Sequences show little vertical organisation in the humid facies in contrast to the progradational upward-coarsening which is usual in the arid environment.

17.7.2

Bashkirian-Moseovian events

A general survey of this interval with climatic, tectonic and sea-level changes was provided by Gjelberg & Steel (1981) and updated for Bjornoya in 1983, with a further tectonic update by Gjelberg (1987). A Serpukhovian to Bashkirian break in deposition is marked by a pre-Gipsdalen Group unconformity or disconformity throughout Svalbard, indicative of uplift and instability, with a brief pause in sedimentation. Moderate deformation in this mid-Carboniferous interval has been recorded in the Billefjorden Group at Midterhuken, where there is a 25-30 ~ angular unconformity between Late and Early Carboniferous strata (Craddock et al. 1985). There was erosion on the East Dickson Land Axis and in the Billefjorden Fault Zone. In Oscar II Land, however, the basal Petrellskaret Formation appears to be conformable on the Vegardfjella Formation and an unconformity of this age is not so obvious on Bjornoya either. Possibly there were breaks within the Nordkapp Formation. Red beds and to some extent, evaporites, are characteristic of this time, with very rapid lateral facies variation. This reflects the strong tectonic control over sedimentation, resulting from uplift of the Nordfjorden Block, with syndepositional faulting at its eastern, and probably western margins. Within the red-bed successions, there is a repeated facies sequence which is especially clear where coarse-grained sediments are found in Inner Hornsund (Hyrnefjellet Formation) and in Billefjorden (Ebbadalen Formation). In the most proximal sequences, upward-coarsening red bed sequences are capped by a shallow-marine quartzitic sandstone. In more distal reaches, the marine sandstone is overlain by dolostone. This can be interpreted in terms of an overall lowering of base level and a marine transgression (demonstrably basin-wide in the case of the Billefjorden Trough at least), producing first a marine reworking of the alluvial surface and then carbonate sedimentation, followed more gradually by the progradation of the alluvial fans. The widespread coarse-grained nature of these sequences suggests that they were started by movement along the bounding faults of their basins. The scale of such sequences (up to 30 m) is consistent with the scale of fault scarps produced by rapidly repeated movements along fault lines in the Basin and Range Province (USA) in historic time. On Bjornoya, continued repetitive outbuilding of alluvial fans can also be recognized in the Landnordingsvika Formation. There the fan deposits are of a more distal nature (Gjelberg & Steel 1981). Clast content of sandstones and conglomerates implies a steady deepening of erosion on the Nordfjorden Block through midCarboniferous time, with successive exposure of Visean, Tournaisian, then Devonian rocks. Evaporites, formed in coastal sabkha environments, are most extensively developed within the Billefjorden Trough. They occur in the Ebbadalen Formation and Minkinfjellet Formation in a linear zone of nodular gypsum/anhydrite rocks between red beds to the west and shelf carbonates to the east. Thin gypsum beds and nodules are also found in the Petrellskaret Formation of western Spitsbergen which only became fully marine in the north in Moscovian time, with deposition of the sandy carbonates of the Scheteligfjellet Formation. In Bashkirian time (Fig. 17.9a), the Ebbadalen Formation was deposited in the East Spitsbergen Basin. Throughout the formation there was an overall upward-fining trend with gradual overlap of non-marine by marine facies, so that the upper part is largely marine. This reflects increasing stability and rising sea levels. Rhythmic intercalations of marine platform and alluvial fan deposits show a characteristic cyclicity which was again probably caused by fault movements lowering the basin floor. Palaeocurrents and facies

CARBONIFEROUS AND PERMIAN HISTORY OF SVALBARD Early

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331

which passed eastwards through a sabkha-evaporite zone, through lagoons to shallow marine carbonates. These sediments were thickest in the rapidly subsiding Billefjorden Trough. The Moscovian Minkinfjellet Formation shows the same facies variation and, at this time, carbonate deposition spread eastwards, becoming more arenaceous in that direction (Fig. 17.9b). This eastward spread of marine environments implies a transgression which resulted in submergence of the Nordaustlandet Block, an area which had not recorded deposition since the Caledonian Orogeny. Here the HArbardbreen Formation (Campbellryggen Subgroup) represents the transgressive deposits at the edge of the basin. These were followed by the sandy carbonates of the Idunfjellet Member. The Nordfjorden Block appears to have separated the East and West Spitsbergen Basins at this time. In the West Spitsbergen Basin, also, fluviatile conglomerates and sandstones in the north and west form the Broggertinden Formation, which passes southwards into marginal marine/lagoonal shales with sandstones of the Petrellskaret Formation. The latter was covered by Moscovian cyclic intertidal/deltaic red beds of the TArnkanten Formation, while further north, sandy marine carbonates of the Scheteligfjellet Formation represent a marine shelf environment. The extent of these basins into southern Spitsbergen is not clear, but the Hyrnefjellet Formation's cyclic alluvial fan red-beds and marine clastics were deposited at some stage throughout Late Carboniferous time, with a source on the Hornsund High to the west of the Inner Hornsund Trough, except for the enigmatic Bladegga conglomerates with their eastern source. The cyclicity here may also be tectonically related, due to sudden marine transgressions as a result of basin floor lowering against a boundary fault, as in Bjornoya where the environment of deposition was similar in the coastal plain red beds of the Bashkirian Landnordingsvika Formation. The lower part of this formation contains coastal fluvial red-bed sequences deposited by sinuous rivers which flowed from the south, there was caliche development in the overbank deposits. The middle part has red alluvial fanglomerates derived from the west (probably from a fault scarp). Marine clastics and later carbonates began to interdigitate towards the top, evidence of the onset of a transgressive regime which continued through the overlying Kapp K5re Formation. Here there was a gradual transition through the limestone, shale and sandstone cycles of the lower Bogevika Member to the limestone dominated Efuglvika Member. This mid-Moscovian establishment of carbonate shelf sedimentation was probably a result of submergence of source areas in the western fault block. The uppermost member catalogues the emergence of a new block in eastern Bjornoya bounded by a NW-SE-trending fault. The shallow marine/deltaic deposits of the Kapp KAre Formation contain evidence of this fault activity in the intraformational conglomerates and the karst and discontinuity surfaces which abound.

17.7.3

Kasimovian-Gzelian events

o

Fig. 17.9. (a) Early Bashkirian lithofacies. (1) Petrellskaret Fm; (2) Broggertinden Fm; (3) little or no uplift; (4) Ebbadalen Fm; (5) periodic uplift; (6) Hyrnefjellet Fm; (7) Landnordrungsvika Fm. (b) Moscovian lithofacies. (1) Tarnkanten Fm; (2) Scheteligfjellet Fm; (3) uplift; (4) Minkinfjellet Fro; (5) Malte Brunfjellet Fm; (6) Idunfjellet Fm; (7) High & Hyrnefjellet Fro; (8) Kapp K~re Fm.

patterns suggest that the trough formed an embayment which opened to normal marine environments in the north (Aga et al. 1986). Strong uplift of the Nordfjorden Block resulted in alluvial fan red beds being deposited adjacent to the Billefjorden Fault Zone,

The latest study of the Moscovian-Kasimovian stratigraphic framework was by Pickard et al. (1996). A late Moscovian transgression over the Nordfjorden Block led to the final phase of Carboniferous sedimentation, characterized by the spread of stable shallow-marine shelf carbonate deposits of the lower Wordiekammen Formation across much of Spitsbergen (Fig. 17.10). The major fault zones of northern Spitsbergen were overlapped as tectonic activity decreased and the Nordfjorden Block was submerged. It was covered by the Kapitol Member which passed laterally into the Cadellfjellet and Morebreen members respectively in the East and West Spitsbergen Basins. However, these basins continued to subside more rapidly. There was an eastward increase in sandstone content in the Cadellfjellet Member, which is replaced by the Idunfjellet Member in Nordaustlandet, indicating an eastern landmass. Dolostones and dolomitic limestones were widely developed, especially in the west (Morebreen

332

CHAPTER 17 Gzelian Iithofacies i

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LMI Fig. 17.10. Gzelian lithofacies map. (1) & (2) Morebreen Fm; (3) Kapitol Mbr; (4) & (5) Cadellfjellet Mbr; (6) Idunfjellet Fm; (7) Horsund High.

Artinskian lithofacies Member) and gypsiferous layers were occasionally developed in the Cadellfjellet Member of the Billefjorden area, indicating a proximity to land. Southwards, at Drevbreen in Torell Land, in the lowest exposed levels of the Late Carboniferous to Permian sequence there, Gzelian carbonates are sandy and intercalated with clastics (Nysaether 1977). In contrast to the stabilization in the north, southern areas of Spitsbergen show evidence of active tectonic control of sedimentation throughout Late Carboniferous and Permian time when the Sorkapp-Hornsund High was uplifted repeatedly. Bjornoya records complex tectonics, with alternating periods of stability and fault activity. The earlier West Bjornoya Basin suffered partial basinal inversion in Moscovian time with repeated uplifts probably causing the erosive conglomeratic influxes characterising the lower part of the Kapp Hanna Formation. This local tectonic activity was the main factor controlling its deposition and must have caused the unconformity at its base, which is followed by extraformational conglomerates, derived from the newly uplifted underlying rocks (in contrast to the intraformational conglomerates of the Kapp K~re Formation). These coarse clastic deltaic influxes, which have a source to the east, re-occur, as evidence of repeated uplift. Late Carboniferous movements resulted in a widespread, though minor, basal Permian unconformity/disconformity on Spitsbergen. Uplift and erosion was strongest in southern Spitsbergen, along the axis of the Hornsund High, where Permian strata rest unconformably on Early Carboniferous or pre-Devonian rocks. They overlie progressively younger rocks towards the north.

17.7.4

A s s e l i a n - S a k m a r i a n events

Kasimovian and Gzelian tectonic stabilization continued. This was associated with a progressive marine transgression onto the positive tectonic features of the Carboniferous Period: the Nordfjorden and Nordaustlandet blocks. Here Early Permian sediments rest unconformably on Devonian and pre-Devonian basement. The Permian transition to more stable platform environments probably reflects the relocation of tensional tectonic regimes to intracratonic rift

~ §

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~]

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~

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[A~

Evaporites

~

Dolomites

[~]

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Limestones

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Fig. 17.11. (a) Asselian lithofacies. (1) Tyrrellfjellet Mbr; (2) Idunfjellet Mbr; (3) & (4) Treskelodden Fm; (5) ?marine carbonates; (6) Horsund High; (7) Kapp Dun6r Fm. 01) Early Artinskian lithofacies. (1) Gipshuker Fm; (2) Kloten Mbr; (3) Zeipelodden Mbr; (4) Hamburgfjellet Fm.

CARBONIFEROUS AND PERMIAN HISTORY OF SVALBARD areas west of Svalbard. This transition was accompanied by a midPermian regional transgression and the establishment of temperate climates in the Svalbard area (Steel & Worsley 1984). Fence diagrams showing the great variation of facies within these formations (Steel & Worsley 1984; Worsley in Aga et al. 1986) may be based on in-house data. By Permian time, most of Svalbard was submerged in a restricted marine or shallow shelf environment. However, the Sorkapp-Hornsund High in southern Spitsbergen remained a positive feature, which was possibly not entirely submerged until Late Permian time. There seems to have been minor uplift of the entire region approximating the Carboniferous-Permian boundary, resulting in the development of laterally extensive stratigraphic discontinuities and intraformational conglomerates. The Tyrrellfjellet Member (upper Wordiekammen Formation) is the principal representative of the Asselian-Sakmarian interval in the north through the whole width of the Isfjorden Basin (Fig. 17.1 la, b). It was dominated by fossiliferous shelf limestones, with local bioherms in the lower part. Subordinate dolostones developed in the central and northeastern part of the basin. Biohermal dolostones dominated the Kapp Dun~r Formation in Bjornoya. Although there are no significant thickness variations, shoals and bioherms tended to develop at the margins of blocks active during Carboniferous time. On Bjerneya and Spitsbergen bioherms occur on the sites of block/trough marginal lineaments, which were temporarily stable at the time. The bioherms created barriers behind which sheltered lagoonal environments developed, where slightly anoxic conditions favoured the preservation of organic material. This is evident in the black bituminous fusuline strata of the Brucebyen Beds in the Tyrrellfjellet Member and at Kapp Dun6r. Repetition of this offshore-barrier-lagoonal facies association points to a series of small-scale regressive cycles, each culminating in the development of a hard ground surface upon which the succeeding bioherm was established as the next transgressive event began. The appearance of these bioherms marks the onset of a more widespread regional regression towards the end of Sakmarian time. In the south, near the strongly uplifted Serkapp-Hornsund High, clastics were more in evidence in the Treskelodden Formation which accumulated on its flanks. Here there was a deltaic transition to marine carbonates across the Carboniferous-Permian boundary. Again, cyclic deposition is seen which may be indicative of regional sea level fluctuations. Meanwhile, in Nordaustlandet, the transgression had been underway since Moscovian time when the HArbardbreen Member transgressive clastics were laid down, followed by the carbonates of the Idunfjellet Member. On Bjerneya, the Sakmarian Stage was a time of considerable folding, faulting, uplift and erosion. Climates were sub-tropical to arid. The plotting of palaeoaplysinid build-ups in North America and Svalbard on a palaeocontinental reconstruction (Skaug et al. 1982) show that most formed between 20 ~ and 40 ~north of the Early Permian equator. Evaporites, associated with the carbonate sequence containing these structures, also suggest warm and arid climates.

333

Meanwhile, on Bjornoya, the Hambergfjellet Formation was being deposited as a transgressive wedge of clastics followed by shallow-marine carbonates, lapping onto a horst which developed in the east of the area and which does not appear to have been submerged at that time (Steel & Worsley 1984). This formation suffered pre-Kungurian erosion. Likewise, in the southern Spitsbergen, there was pre-Kungurian erosion of the upper part of the Treskelodden Formation. The different lines of evidence thus point to an Artinskian hiatus, between the Gipsdalen and Tempelfjorden groups. There is evidence in several areas of a discontinuity at the base of the Tempelfjorden Group. Intraformational breccias (e.g. the Kloten Breccia) are a distinctive feature of the dolostones of this interval. They are stratified rather than structural and have been interpreted as collapse breccias due to disturbances related to volumetric changes between anhydrite and gypsum. Halite may have been present and dissolved out but we have no record of Late Paleozoic halite in Svalbard. On the other hand the diapiric structures beneath the Barents Sea are possibly coeval and must imply substantial halite deposits. Worsley (Aga et al. 1966) mentioned that some sinistral strikeslip may have persisted through Carboniferous to Permian time with transpression in the Hornsund and Bjorneya areas. If so, this would be effective within an offshore fault system such as the postulated Palaeo-Hornsund-Bjornoya Fault Zone.

17.7.6

Kungurian-Guadelupian events

The final phase of Permian sedimentation in Svalbard resulted in the deposition of siliceous rocks of the Tempelfjorden Group Ufimian

lithofacies

I

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This was a time of deposition in warm shallow seas, tidal and supratidal flats with restricted circulation and variable salinity. The late Sakmarian regional regression culminated in the development of sabkha environments which spread eastwards. These lagoonal and sabkha sediments of the Gipshuken Formation are preserved within the Isfjorden Basin. Gypsum and anhydrite deposition is restricted generally to areas west of the Billefjorden Fault Zone, passing eastwards into a shelf carbonate zone which becomes arenaceous as the Permian land area to the north is approached. Later Artinskian time was characterized by more widely developed shelf limestone deposition in Spitsbergen, surrounding a narrow dolomite zone and a central evaporite region, with dolomites in the upper part in Nordaustlandet (Fig. 17.11b).

.

§ . ,

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17.7.5

....

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.

§

g

.~.S~ ~

]~

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Limestones

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Cherts ~Sponge build-ups .M,~

Fig. 17.12. Ufimian lithofacies. (1) Kapp Starostin Fm - shale-chert; (2) Kapp Starostin Fm-chert-sand; (3) Hornsund High; (4) Tokrossoya Fm; (5) Miseryfjellet Fm.

334

CHAPTER 17

(Fig. 17.12). In Spitsbergen, they include the widespread Kapp Starostin Formation, and its southern equivalent, the Tokrossoya Formation and in Bjornoya, the Miseryfjellet Formation. The sharp contact between the carbonate-dominated Gipsdalen Group and the cherty sequences of the Tempelfjorden Group represents a major facies change reflecting a large-scale transgression at the time of transition from warm arid to cool temperate humid climatic conditions. There was also a shift from carbonate-dominated to clastic-dominated sediments, and the appearance of significant amounts of chert-derived from sponges. The sponge habitat was suggested by Worsley (in Aga et al. 1986) to indicate that the sea was at least 200 m deep. We have no evidence of syn-sedimentary faulting in central Spitsbergen or on Bjornoya at this time, though preferential downwarping did occur along lineaments bounding the Nordfjorden Block and thicker sequences fill the troughs on either side of it. Eastern areas show a thinner stable platform development as does Bjornoya, where basal deposits of the group rest on a peneplain surface which cuts across all older units. In contrast, in southwest Spitsbergen, the Hornsund High was positive throughout Late Permian time and sequences thin dramatically against the eastern margin of this structure. The Tokrossoya Formation is a thick sequence, probably deposited off the southwest margin of the High. The basal beds of the Kapp Starostin Formation commonly consist of bioclastic limestones (the Voringen Member), with a sharp and commonly karst contact with the underlying Gipshuken Formation. It is quite clear that these limestones, which are interpreted as shoreface deposits formed by the transgression of barrier sequences over the restricted marine platform and sabkha environments of the Gipshuken Formation during the early phases of the transgression, do become more sandy in many areas. These clastics indicate a regional reduction in sea level across the Artinskian-Kungurian boundary, with rejuvenation of fluvial systems. The basal beds grade up into the spiculitic shales and siltstones of the Svenskeegga Member, which are the main lithofacies of the formation, especially in trough areas. Abundant trace fossils clearly indicate low-energy, but oxygenated bottom environments, well below normal wave base, and various interbedded units include bioclastic or sandy shoals which are most common on eastern platform areas. Sandstones are found only in the uppermost part of the sequence in northwestern areas (Fig. 17.12), where they may indicate regression; these have a high glauconite content and are heavily bioturbated, both features which suggest relatively low rates of deposition in intermediate water depths. In the southwest, major upward-coarsening sequences are seen wedging onto the margins of the Sorkapp-Hornsund High. Thinner sequences immediately adjacent to the high show either fine-grained silty limestones or complex highly condensed sequences with both intra-and extraformational clasts. Both facies types rest on eroded or karstic surfaces of the Gipsdalen Group. No Kapp Starostin Formation rocks are present on the high itself. There is further evidence here of uplift and erosion/non-deposition prior to the deposition of the uppermost Hovtinden Member, which oversteps the underlying members of the Kapp Starostin Formation to lie on the eroded top of the Early Permian Treskelodden Formation at Treskelen. The Tokrossoya Formation to the southwest of the High also shows a large-scale upward-coarsening sequence, passing from spiculitic siltstones into sandstones interpreted as beach sands or peritidal sand waves. The upward-coarsening along both margins of the high suggests that the transgression which initiated the group's deposition may have submerged it, but that there was subsequent uplift. This high appears to be bounded on the east by the Kongsfjorden-Hansbreen Fault Zone (KHFZ) and possibly on the west by the Palaeo-Hornsund Fault. If so, it was not the direct successor to the previous Hornsund-Sorkapp High which was to the east of the KHFZ while the Hornsundneset Formation indicates subsidence to the west of the KHFZ. The Miseryfjellet Formation of Bjornoya consists of sandy limestones and well-sorted sandstones deposited in shallow, well-

agitated environments on the peneplain surface of the newly submerged structure. The uppermost beds of the group are probably not younger than early Capitanian and this Late Capitanian-Lopingian hiatus in Svalbard is not understood. Basal Triassic rocks overlie Permian strata, generally without apparent unconformity, although there is a sharp change in lithology and locally some discordant attitudes. There is some evidence of a disconformity on Edgeoya, where there is a sharp, locally erosive, junction with the basal Triassic siltstones and sandstones. These contain glauconite, an indication of slow sedimentation, which may have been reworked from Permian rocks. In southern Spitsbergen, Triassic rocks are strongly unconformable as a result of further uplift of the Sorkapp-Hornsund High.

17.7.7

Latest Permian events

The enigma of Late Permian history remains. In America and Europe, including Svalbard and western Russia the biostratigraphic record is very poor in contrast to that in the eastern Tethys and especially southern China. There has long been a gap in Svalbard knowledge possibly corresponding to a gap in the record. This possibility was somewhat reinforced by the work of Nakazawa et al. (1990) who, from biostratigraphic work on the succession south of Van Keulenfjorden, correlated the latest Hovtinden Member (Kapp Starostin Fm) fossils with Chinese records and found only early ?Wordian similarity, suggesting that the whole Capitanian, Longtanian and Changxingian stages would be missing. On the other hand, Wignell & Twitchett (1996) suggested that the lowest Vardebukta Formation strata (hitherto regarded as Triassic) are Permian. This would confirm the hiatus, if it be a hiatus, to fall within the Permian Period and thus correspond to the minor discordances at the Tempelfjorden and Sassendalen groups boundary. Speculation, world-wide, has long attended the PermianTriassic boundary with ideas of salinity and or anoxic events related to sea level change (e.g. Gramberg 1959). Gruszczynski et al. (1987, 1992) reported on the sea-water isotopic perturbation at the boundary. They claimed dramatic perturbation in strontium, carbon and oxygen isotope curves near the top of the Kapp Starostin Formation. Their model proposed replacement of a largely stagnant stratified ocean by a vigorously mixed one at the Permian-Triassic boundary. Relatively local tectonic and oceanographic events may be seen in the evolution of the Ural Orogeny spanning Late Permian and Early Triassic time (Otto & Bailey 1995).

17.7.8

Carboniferous and Permian sedimentation rates

In so far as significantly deep water facies have not been encountered sedimentation rates are virtually the same as subsidence rates in a marine sequence (Table 17.2).

Table 17.2. Carboniferous and Perm&n sedimentation rates (in per million years) (from Stemrnerick & Worsley 1989)

SW Nordaustlandet NE Ny Friesland NE Tempelfjorden Btinsow Land Inner St Jonsfjorden N Sorkapp Land S Sorkapp Land Bjornoya

Carboniferous

Permian

Early

Late

Early

<5 5-10 <5 30 35-40 15 15

15 20-50 25 20-50 (30) 50 15

10

5

5-10 10 10 15 2

Late 15

25 35 25 50 ?15

CARBONIFEROUS AND PERMIAN HISTORY OF SVALBARD 17.8 17.8.1

335

Carboniferous and P e r m i a n p a l a e o g e o l o g y

Siberian

Palaeotectonic relationships Pronchishchew

The sub-Carboniferous unconformity marks the end of differential displacements between the constituent terranes of Svalbard and the beginning of the consolidated platform that lay to the north of eastern North Greenland and as a constituent of the newly formed Laurussia (Laurentia & N Europe) supercontinent. In this position, which lasted also through the Mesozoic Era, Svalbard's connexions were with the Sverdrup Basin to the west, with the Wandel sea Basin to the south, with the Timan-Pechora Basin and most of the Russian Arctic to the east, and with the Lomonosov Ridge to the north. It cannot, thus, be considered as an island archipelago, but as part of an extensive platform, remote from any ocean deep, and often submerged by shallow seas or raised up above sea level to shed sediment elsewhere. As we have seen, Carboniferous and Permian Svalbard progressed from mobile zones of subsidence and uplift to uniform facies on a stable shelf. Moreover, these circumstances, while extending beyond Svalbard, were somewhat peculiar to it because to the west, in the Queen Elisabeth Islands, the Devonian diastrophism continued into Early Carboniferous time with the Ellesmerian Orogeny so that the Sverdrup Basin stabilised later than in Svalbard. To the south, in East Greenland, already midPermian dextral transtension is evident along N-S shear zones (Coffield 1993). To the far south Late Paleozoic plate motions resulted in the Appalachian and Hercynian orogenies which consolidated Gondwana with Laurussia. Even within Svalbard there was relative mobility towards the south as seen in south Spitsbergen and Bjornoya. These events dominated Permian time with continental facies throughout much of western Europe and Greenland south of the Wandel Sea Basin. To the east, the Uralian geosyncline was to suffer Late Permian and Early Triassic orogeny, which accounts in part for the poor Late Permian marine record in the Arctic. Svalbard escaped these disturbances and, with the final consolidation of Pangea by the closing of the Uralian Ocean, was the forerunner of the widespread stable Mesozoic platform which extended throughout the Arctic. Some of these relationships are shown in Fig. 17.13 from (a) Early Carboniferous and (b) Late Permian time.

17.8.2

Palaeosedimentary relationships

Figure 17.14 plots an approximate Carboniferous and Permian correlation between Svalbard units as described above and well known formations in neighbouring areas. Figure 17.15a-f, in a key and five maps, plots an approximate palinspastic distribution of facies. These maps and those in similar format and ornament in the succeeding Chapters 18 (Triassic) and 19 (Jurassic-Cretaceous) are based on the series of maps in the Barents Shelf symposium volume (Harland & Dowdeswell 1988). The following commentary in time sequence is similarly based on that, especially on Russia by Heafford, but also updated and extended to the Queen Elizabeth Islands of Arctic Canada (Davis & Nassichuk 1991) and in the Wandei Sea Basin of North Greenland (e.g. by Stemmerik & Worsley 1989) and through the Barents shelf for the Permian story (Stemmerik & Worsley 1995).

(1) Mississippian (Early Carboniferous) Fig. 17.15b North Greenland. The Sortebakken sequence is confined to Holm Land and sedimentation was related to tectonism producing internal unconformities which separate rhythmic sandstone and shale cycles. An unconformity divides a shaly lower part and a sandy coal-bearing upper part (HAkansson & Stemmerick 1989). Franz Josef Land. Although mainly a Mesozoic terrane, outcrops and boreholes contain mottled sandstones and shales

.'.

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Fig. 17.13. Palinspastic tectonic maps, redrawn from Heafford & Kelly (1988, figs 1 and 2, pp. 20-21). (a) Principal Carboniferous tectonic events, (b) principal Permian tectonic events.

which are coal bearing. Dibner (1982) suggested a Visean age so that they could correspond to part of the Billefjorden Group in Svalbard. Novaya Zemlya. Eight biostratigraphic zones have been distinguished. In the 'western zone' limestones are massive, fossiliferous, frequently silicified and contain dark argillaceous limestones. Gypsum and anhydrite occur in the Kostin Shar region9 Terriginous admixtures occur in the east. Timan-Peehora region. Tournaisian regression exposed a large land mass and erosion exposed Late Frasnian strata except in the Denisov embayment which shows continuous deposition of thick

CHAPTER 17

336

Ma .~ ~_ o ~

z

Changxingian Longtanian

SVERDRUP BASIN

-245 -

SVALBARD

Spitsbergen

WANDEL SEA BASIN

Bjornoya

l lJJJIltllIllllllLI

-250 -

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Rotliegengendes

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(Kim Fjelde)

Mallernuk Mountain Group

Wordiekammen

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Van Hauen

Kapp Hanna

Stephanian

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Kasimovian (Kas)

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Minkint]ellet Fm

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Westphalian , ~311- ,

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Bashkirian (Bsh)

I r 323 1 I ~

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Fm

Marsdenian (Mrd) Kinderscoutian (Kin) Aleortian (AID) Ch0kierian (Cho) Arnsbergian (Arn)

Hultberget Fm

Borup Fiord

Serpukhovian (Spk)

~, Mumien Fm Nordkapp Fm

Emma Fiord

Visean (Vis)

Sortebakken , ~ 350 ~ ,

_~

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~;

BriQantian (Bri) Asbian (Asb) Holkerian (HIk) Arundian(Aru) Chadian (Chd) Ivorian (Ivo)

H6rbyebreen Fm

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Chemov

Vychegodskiy

Solikamskiy

Iren'skiy

Iren'skiy Filippovskiy

Belosnezhkin

Komichanskiy Nerminskiy

Ikskiy

Sokolin Byrranga

Sterlitamakskiy

Ilibiskiy

Tastubiskiy

Nenetskiy Kokhanskiy Indigskiy Sokoryegorskiy Noginsky

Verkhne Turuzov

Klaz'minsky

Dorogomilovsky

Krevyaninsky Myachkovsky

Podolskian (Pod)

Podorsky

Kashirskian (Ksk) Vereiskian (Vrk) Melekessian (Mel)

Kashirsky Vereiskiy

(Che)

Melekessky

Cheremchanskiy Prikamsky Severokeltenskiy Krasnopolyansky

Protvinsky Steshevsky Tarussky Venevsky

Mikhailovskiy Aleksinsky Turskiy

Bobrikov Radayev Yelkhov

Ilychskiy Pester'kovskiy

Kos'vinskiy Kizelovsky

Tournaisian (Tou)

~z

Sheminshskiy

Pendleian(Pnd)

~ . - 333- ,

a.

Ust'kulomskiy

(Mya)

Kape K~re Fm

Zverlinsk

Khamovnichesky

Cheremshanskian .~

Chev'ynskiy

Lower Kazanskiy

Krevyakinskian (Kre) Myachkovinskian

Hare Fiord

Moscovian (Mos)

X r

Noginskian (NOG) Klazminskian (Kla) Dorogomilov~kian Cha m~

"~ iE ~ 303 ~

z----"

Sezymian Autunian

Fm

Gzelian (Gze)

Upper Kazanskiy

Pel'skiy

Channel -290- ,

Veslyanskiy

Vyl'skiy

Artinskian ? Hambergfjellet Fm

Urzhuminskiy

Pay Khoyian

Kupferschiefer Weissleigendes Gipshuken Fm

Sakrnarian (Sak)

Pytyr'yuskiy

SIBERIA

Tvetochinsk

Zechsteinkalk

Kungurian (Kun)

EUROPEAN PLATFORM

Aller

Leine Strassfurt evaporites Hauptdolomit

Trolle Land Group

Trold Fiord

TIMAN PECHORA

Red clays and marls Vyatskiy $eveodvinskiy

Ohre

Capitanian

Artinskian (Art)

USTRITSIA 1983

Buntsandstein

(White cherts)

N

WESTERN EUROPE

ReedvikaFm

Hastarian (Has)

Onerepetsky

Famennian (Faro)

Katinovsky

Upinsky Malevsky

363Late Devonian

Zavolzhsky

I|~r-'~

Fig. 17.14. International correlation of Carboniferous and Permian formations in the Arctic.

carbonate successions. Further east clastics (Dzhebol Formation) formed in deeper water providing minor sandstone reservoirs. Visean transgression gave continuous deposition of marine shelf carbonates which continue their Permian and Visean anhydrite. They form local hydrocarbon seals. Wandel Sea Basin. Moscovian marine transgression resulted in deposition of sandstone and thick-bedded biomicrites (H~kansson & Stemmerik 1989). Sverdrup Basin. Ellesmerian tectonism spanned Late Devonian and Early Carboniferous time and so appears to have precluded other than a fragmentary early Mississippian sedimentary record. However, the Ellesmerian Orogeny had in effect run its course by the end of Tournaisian time so that Visean Emma Fiord Formation occurrences indicate the beginning of the Carboniferous and Permian history of the Sverdrup Basin (Davis & Nassichuk 1991). The Sverdrup Basin, with outcrops several times more extensive than those in the Spitsbergen Basin, then reveals a comprehensive basin sequence with distinctive central and marginal facies, with complex configuration and interdigitating formations that can only be mentioned in passing here and in Fig. 17.14.

(2) Early Pennsylvanian (Bashkirian and Moscovian) Fig. 17.15c) ( : Middle Carboniferous of Russian authors). Sverdrup Basin. The Borup Fiord Formation matches rather well the Hultberget Formation of Spitsbergen probably spanning the SerpukhovianBashkirian boundary after a possible early Serpukhovian hiatus.

Both formations introduce red beds (the Borup Fiord Formation with conglomerates) which precede the evaporite sequence in both basins, which in the Sverdrup Basin is the Otto Fiord Formation. The Moscovian carbonate facies extend almost throughout the basin. North Greenland (Wandei Sea Basin). Moscovian carbonates, the Mallemuk Mountain Group, of cyclic shallow-marine clastics and limestones, with thick conglomerate at the base of each of three 'mega-cycles', replace clastics through to Early Permian. (cf. the Moscovian transgression in Svalbard). Franz Josef Land. Middle Carboniferous limestones occur as blocks in Triassic strata (Dibner & Krylova, 1963). Novaya Zemlya. A black polymict conglomerate initiates the mid- (and Late) Carboniferous deposition which otherwise continues Early Carboniferous facies. Timan-Peehora. Middle Carboniferous limestones and dolostones have fairly good reservoir properties. Disconformities may give vuggy reservoirs (Ulmishek 1985). The pre-Ural foredeep developed and migrated westwards, especially in the south. Deepwater black shales and dark bituminous limestones, which accumulated in the constituent Bolshesyna and Kosyu-Rogov troughs, were separated from the Timan-Pechora platform by barrier reefs to the west (Ulmishek 1985). A zone of carbonate breccias formed along the base of the inferred slope between shallow-water platform and deep water deposits. Reefs and breccias are targets for exploration. There are indicators of impending Early Uralian tectogenesis.

Fig. 17.15. Sequence of Carboniferous through Permian facies distribution palinspastic maps redrawn and updated by S. R. A. Kelly from Heafford (1988), figs 3, 7, 8, 10, 12 respectively): (a) Legend. (b) Early Carboniferous. (e) Bashkirian-Early Moscovian. (d) Asselian-Sakmarian. (e) Artinskian-Kungurian. (f) Ufimian.

338

CHAPTER 17

Fig. 17.15. (continued)

(3) Late Pennsylavanian (Kasimovian and Gzelian) ( - L a t e Carboniferous of Russian authors). North Greenland. The clastic input ceased. Novaya Zemlya. Erosion removed much of the late Carboniferous strata, but absence of clastic products of this uplift is ascribed to gentle down-warping and chemical weathering.

(4) Early Rotliegendes (Asselian-Sakmarian) Fig. 17.15d. Sverdrup Basin. Carbonate facies continued throughout most of the basin, except for the Mt Bayly Formation, with evaporite facies interdigitating with the Belcher Channel Formation to the SE and Nansen Formation to the N W with Hare Fiord and Van Hauen formations in the deeper basin. The evaporites match rather closely those of the Gipshuken Formation of Spitsbergen. North Greenland. Thick carbonate sequences in the Mallemuk Mountain Group, also with bioherms, continued. Early Permian renewed transgression expanded deposition to include northern Amdrup Land. Novaya Zemlya. Mid-Asselian down-warping and rapid subsidence resulted in marls and lutites with stunted or absent benthos, pyritization and flint intercalations, i.e. deep stagnant bottom conditions. There were no uplifts supplying sediment in the Urals north of the Arctic Circle in earliest Permian time and in contrast to the central Urals (Ustritskiy 1977). Timan-Pechora. Petroleum reservoirs are found in Asselian palaeoaplysinid bioherms. Locally (e.g. Khoreyven Basin) petroliferous bioherm and foram limestones occur up to 100-150m thick (Slivkova et al. 1976). Concentration of reservoirs is on structural highs. Inversion of parts of the Pechora-Kolva aulacogen beginning in Late Devonian-Mississippian time may herald the start of

the Uralian orogeny. Early Permian Clastics slowly invaded the Timan-Pechora platform from the east, gradually replacing the limestone.

(5) Late Rotliegendes (Artinskian & Kungurian)Fig. 17.15e. Sverdrup Basin. The 'Mellvillian Disturbance' was named by Thorsteinsion & Tozer (1970) for an episode of folding and faulting between the deposition of late Carbonifeorus and late Permian strata observed at two localities at the margin of the Sverdrup Basin (Davis & Nassichuk 1991). Such a disturbance might well correspond to the presumed hiatus between the Gipsdalen and Tempelfjorden groups. North Greenland. Clastic input continued through to Triassic time. In Peary Land late Early Permian carbonates were replaced by deep shelf shales, which then gave way to shallower water sands. In south Amdrup Land carbonates were interbedded with sandstones. Hfikansson & Pedersen (1982) suggested 200kin of dextral strike-slip along the Harder Fjord Fracture Zone in latest Permian time on the basis of a low-angle unconformity between Triassic and Late Permian strata and the existence of latest Permian continental strata within the fracture zone, but there may be no displacement across the Tanquary High in Ellesmere Island. Coffield (1993) reported N-S zones of dextral transtension. Novaya Zemlya. Infilling of the basin continued. Arenaceous material derived from a sediment source east of the present day Urals. Also boulders of carbonate slumped from the east. By Kungurian time, the southeast part of the Novaya ZemlyaPay Khoy basin had been completely infilled and paralic and coalbearing strata followed. On Vaygach, shallow-marine sediments

CARBONIFEROUS AND PERMIAN HISTORY OF SVALBARD contain rich benthic fauna. Thin abyssal sedimentation ensued west of Novaya Zemlya. Ufimian strata comprise 3 km of clastic sediments varying from continental coal facies in the southeast to marine in central South Island with turbidites and slumps. Late Ufimian shallow seas obtained throughout the area. Unlike the Fore Urals Trough, the Novaya Zemlya basin provides no evidence at this time of westerly migration of its axis (Heafford & Kelly 1988) Timan-Pechora. Locally emergent highs expanded in the Timan-Pechora Platform in Kungurian time, restricting marine circulation and leading to thick accumulations of evaporites (halite and anhydrite) in the Pechora depression to the south and form regional seals (Heafford & Kelly 1988).

(6) Early Zechstein Fig. 17.15f. The Zechstein Sub-Period is divided here (Harland et al. 1990) into Guadelupian (Early Zechstein) and Lopingian (Late Zechstein). The early Guadelupian (Ufimian and Wordian) is probably well represented in the Arctic region considered here. After this Capitanian (later Guadelupian) and Lopingian are difficult to correlate if present. Sverdrnp Basin. The uppermost Permian formations tend to muddy and sandy facies (Trold Fiord Formation) with a dolostone unit (Degerbols Formation). This corresponds to the Spitsbergen Kapp Starostin Formation and its equivalents in the Tempelfjorden Group.

339

North Greenland. The Trolle Land Group of sandy facies also correspond to the Tempelfjorden Group except that Stemmerik & Worsley (1989) depicted it as spanning Ufimian almost through Tatarian time. The evidence for Tatarian correlation is not known here.

(7) Capitanian and Late Zechstein (Lopingian). Sverdrup Basin. The presumed Permian-Triassic boundary is marked by a regional unconformity below which all of the post-Wordian (post-Kazanian) record is missing (Davis & Nassichuk 1991). This appears to match the post-Kapp Starostin hiatus in Spitsbergen. According to the IUGS procedures, the Permian-Triassic boundary would be defined in a global stratotype section and point (GSSP) to be agreed. It is taken here as at least generally accepted to be at a GSSP somewhere that would at first include Otoceras or Hypophiceras zones as Triassic. Such a point was suggested by Tozer (1967) in the Canadian Arctic; but a Tethyan standard may be better and the situation may have moved on since the author's discussion of the problem (Harland et al. 1990 p.50). Northwest Russia. Late Kazanian and Tatarian successions are typified by continental sandy facies, often reddish. They are difficult to correlate internationally. It is presumed here that the loss of a Late Permian marine record is associated with early phases of the Uralian orogen.

Chapter 18 Triassic history W. B R I A N 18.1 18.2 18.3 18.3.1 18.3.2 18.3.3 18.4 18.4.1 18.4.2 18.4.3 18.5 18.5.1 18.5.2 18.5.3 18.5.4

HARLAND

with contributions with ISOBEL GEDDES

Early work, 340 Structural frame, 343 Triassic rock units, 344 The rock unit scheme, 345 The Sassendalen Group, 347 The Kapp Toscana Group, 348 Triassic time scale and international correlation, 350 The standard international scale, 350 Biostratigraphic correlation, 351 Magnetostratigraphic correlation (W.B.H. & I.G.), 353 Triassic biotas, 353 Vertebrates, 353 Conodonts, 354 Molluscan faunas, 354 Bryozoans, 355

The Triassic Period of about 40 million years duration spanned about a third of that of the Carboniferous and Permian interval. The Triassic rocks of Svalbard are easily distinguished from the underlying Permian strata because of a distinct disconformity between them and a marked contrast in facies from the resistant, pale coloured, cherts and siliciclastics of the Kapp Starostin Formation to the softer, darker areno-argillaceous Vardebukta and equivalent formations. Figure 18.1 shows the distribution of Triassic strata in Svalbard. The minor angular unconformity represents a hiatus mainly in the Permian rather than the Triassic record. The dominantly argillaceous facies constitute the Early Triassic to Late Middle Triassic Sassendalen Group. The rocks can be well dated from ammonoids, typically within calcareous concretions in the shales. The succeeding Kapp Toscana Group is distinguished by a dominantly sandy deltaic facies in which age determinations are difficult. It spans both Late Triassic and Early Jurassic epochs (roughly mid-Ladinian to mid-Bathonian). The Triassic-Jurassic boundary is not easy to estimate. Nevertheless towards the end of Triassic time (e.g. Rhaetian) the overall scene changed. Thus of the three formations of the Kapp Toscana Group the lower two (Tschermakfjellet and De Geerdalen) belong to the Triassic story. The overlying Wilhelmoya Formation may possibly range from Latest Triassic through Liassic time, and due to its complexity it is also discussed in the Jurassic-Cretaceous chapter (19). The facies of the two groups reflect two distinct environmental configurations. The Sassendalen Group was deposited on a distal marine muddy shelf with a delta prograding from the west bringing in coarser sediments. A northeastern source area appeared during the deposition of the Kapp Toscana Group so that a new deltaic system came to dominate. In the following history of research, we may attribute part of the intense interest in Svalbard Triassic rocks to their distinct marine and fossiliferous facies in contrast to most Triassic strata in Europe. Economic interest has centred on two different aspects, but each of marine origin of the Sassendalen Group. Early Swedish

18.5.5 18.5.6 18.6 18.6.1 18.6.2 18.6.3 18.6.4 18.6.5 18.7 18.7.1 18.7.2 18.7.3

Flora, 355 The Rhaetian problem, 356 Sequence of Triassic environments (W.B.H. & I.G.), 356 Early Scythian (Griesbachian and Dienerian = Induan of Russia), 356 Later Scythian (Smithian and Spathian = Olenekian of Russia), 357 Mid-Triassic (Anisian and Early Ladinian), 358 Late Triassic (latest Ladinian, Carnian, Norian and Rhaetian), 358 Bjornoya, 361 Triassic regional palaeogeology, 361 Tectonic framework, 361 Triassic palaeolatitudes and climates, 362 Sedimentary connections, 362

geologists planned to exploit the phosphorite. The high organic content of marine shales has favoured Sassendalen Group strata as a source for hydrocarbons.

18.1

Early work

A survey of Triassic research in Svalbard introduced a comprehensive attempt to establish contemporary lithostratigraphic units and so to subsume the many previous schemes, based largely on palaeontological investigations (Buchan et al. 1965). This introduction follows only the early events and thereafter the flood of research is referred to in context. After Lamont's 1859 collection of Edgeoya material (1860), the early Svalbard Triassic studies were largely Swedish, notably by A. E. Nordenski61d, then G. De Geer and A. G. Nathorst. Their results were primarily palaeontological. Blomstrand (1864) perhaps made the first observations on Spitsbergen Triassic rocks. Their Triassic age was established by Lindstr6m in 1865 on the basis of comparisons with ammonites of the Hallst~itter strata of Austria. The first account of this work in English being a translation of Nordenski61d's 1866 paper (1867). 1868 and 1870 saw Swedish expeditions to Kapp Thordsen (southern Dickson Land) partly for the study of ichthyosaurs and partly to investigate and even to exploit the phosphorite deposits. Fossils were described: invertebrates by Oberg (1877) and vertebrates by Wiman (1910a, b). A hut and ropeway was established to mine the phosphorite at Kapp Starostin, but a fatal tragedy struck a wintering party. E. V. Mojsisovics (1886) reviewed Triassic ammonoid faunas of the Arctic and earlier work was consolidated in three faunal groups: Posidonomyenkalk, Daonellenkalk and 'Schichten mit Halobia zitteli' the first two being regarded as Muschelkalk and the third as Norian. Sir Martin Conway's 1896 party crossing Spitsbergen from Sassenfjorden to Agardhbukta included E. J. Garwood and J. W. Gregory. Their ammonoid collection was listed by Spath (1921)

Fig. 18.1. Outcrop map showing the distribution of Triassic deposits in Svalbard. More detailed maps and sections apear in Chapters 4, 5, 6, 9, 10 and 11. Key to numbered localities: (1) Agardhbukta; (2) Ahlstrandodden; (3) Akseloya; (4) Barentsoya; (5) Bellsund; (6) Bertilryggen; (7) Bjornoya; (8) Botneheia; (9) Bravaisberget; (10) De Geerdalen; (11) Deltadalen; (12) Dickson Land; (13) Drevbreen; (14) Duckwitzbreen; (15) Edgeoya; (16) Festningen; (17) Flatsalen; (18) Fridjovhamnha; (19) Gronfjorden; (20) Gustav Adolf Land; (21) Hopen; (22) Hornsund; (23) Isfjorden; (24) Iskletten; (25) Iversenfjellet; (26) Kaosfjellet; (27) Kapp Johannesen; (28) Kapp Koburg; (29) Kapp Lee; (30) Kapp Starostin; (31) Kapp Thorsden; (32) Kapp Toscana; (33) Kistefjellet; (34) Kong Karls Land; (35) Kongressfjellet; (36) Kvalpynttjellet; (37) Lyngefjellet; (38) Midterhuken; (39) Miseryfjellet; (40) Mistakodden; (41) Mohnhogda; (42) Nathorst land; (43) Negerpynten; (44) Nordaustlandet; (45) Nordenski61d Land; (46) Ny-Alesund; (47) Olav V Land; (48) Osbornebreen; (49) Passhatten; (50) Rotundafjellet; (51) Sabine Land; (52) Sassendalen; (53) Saurieberget; (54) Selmaneset; (55) Siksaken; (56) Siogrenfjellet; (57) Skuld; (58) Somovbreen; (59) Stensi6fjellet; (60) Sticky Keep; (61) Storbreen; (62) Sveaneset; (63) Tjuvfjorden; (64) Torellnest)ellet; (65) Treskelodden; (66) Trygghamna; (67) Tschermakfjellet; (68) Tumlingodden; (69) Tvillingodden; (70) Urd; (71) Vardebukta; (72) Verdande; (73) Vikinghogda; (74) Vindodden; (75) Wallenbergfjellet; (76) Wichebukta;

TRIASSIC HISTORY

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TRIASSIC HISTORY and described (1934). Their description of the rock succession (Gregory 1921), while overtaken by Nathorst's (1910) monograph on Svalbard geology, provided a clear picture of the rock succession (as follows). Section 1 approximate as given Thickness (in feet) G. Plateau Flags: yellowish, unfossiliferous, shaly flags (400) 132 m F. Upper Nodule bed E. Oozy Mound beds: thin dark grey to black shales with phosphatic nodules Fossils in three seams. (3) Upper seam-belemnites (2) Middle seam-Daonella, etc. (1) Lower seam-No. 31-5 These shales pass down to shaly flags with the ribbed Pseudomonotis E&F (400) 132 m D. Escarpment Shales (200) 65 m (4) A 3 in. Limestone (3) Thin paper shales with many Ammonites, reptilian bones, etc. (2) Middle Nodule bed (1) Earthy Limestone C.2 Black shales and yellow flags: with fish, mollusca, etc. and abundant Posidonomya;

Garwood found a reptile rib C.I. Lowest, Nodule bed B. Unfossiliferous black shales: few exposures A. Carboniferous Limestone

(600) 197m (500) 164 m

The above fits well the modern scheme of rock units (Buchan et al. 1965) and its correlation is shown in Fig. 18.2. The 1898 Russo-Swedish Arc of Meridian Survey indentified Triassic rocks in Nordaustlandet (De Geer 1923). The eleventh International Geological Congress in 1910 in Stockholm put out an international excursion from Stockholm to Spitsbergen led by De Geer (1910; Lamplugh 1910) Isfjorden outcrops were visited, especially Tschermakfjellet (and Kongressfjellet) where newly interested paleontologists extended their international experience. In 1910 Wiman's vertebrate studies led to a stratigraphic scheme and map. Also in 1910 Nathorst's monograph on the geology of the archipelago included fossil lists. While most of Europe was preoccupied with World War I Swedish expeditions continued and Norway, through Hoel, began a distinguished series of investigations in 1914 culminating in the complete measurement of the Festningen section ( H o d & Orvin 1937). Invidious though it seems to select contributions from further expeditions (one or two a year each with some incidental input to Triassic knowledge) mention is made of Watkin's 1927 Cambridge Expedition to Edgeoya on which Falcon (1928) divided the (Triassic) rocks of the island into an 'Upper Sandstone Group', a 'Purple Shale Group' and an underlying 'Oil Shale Group'. Collections from the above enabled Buchan et al. (1965) to extend their scheme to Edgeoya. After the measurement of the Festningen section perhaps the principal contribution to Triassic stratigraphy was by Frebold who worked on the Norwegian collections and produced a significant synthesis (1929, 1930a-c, 1935). International activity intensified after World War II adding, to Norsk Polarinstitutt workers, groups from Britain and Poland especially. Frebold brought his Mesozoic studies to a new synthesis (1951). From 1960, with the new interest in Arctic petroleum potential, American and Russian participation began. The time was ripe for both a systematic review and synthesis of Triassic results to date. This was attempted by the Cambridge Group (Buchan et al. 1965). Earlier work supplemented by newly measured sections led to a lithostratigraphic scheme based on 30 sections in Spitsbergen which, with little modification, has been generally in use. However such a review provided a platform for further investigations which are listed here.

General. Gazdzicki & Trammer (1978, Lower Triassic tidal deposits); Edwards, Bjaerke, Nagy, Winsnes & Worsley (1979, stratigraphy of E. Svalbard); Pickton, Harland, Hughes & Smith (1979 reply to Edwards et al.); Mork & Worsley (1979, stratigraphic review); Pchelina (1980, Triassic-

343

Jurassic boundary); Korchinskaya (1982, Triassic stratigraphic scheme); Mork, Knarud & Worsley (1982, depositional and diagenetic environments); Pchelina (1983, Mesozoic stratigraphy); Knarud (1984, environment & palaeogeography of Upper Triassic); B/ickstr6m & Nagy (1985, the Brentskardhaugen Bed- depositional history and fauna); Heafford (1988, Carboniferous to Triassic palaeogeography of the Barents Shelf); Worsley (1985, Late Paleozoic and Early Mesozoic stratigraphy); Birkenmajer (1977, Triassic of Hornsund area); Bjaerke & Dypvik (1977, sedimentology & palynology in Sassenfjorden); Weitschat & Lehmann (1978, Smithian biostratigraphy, Botneheia, W. Spitsbergen); Worsley & Mork (1978, Triassic stratigraphy of southern Spitsbergen); Wierzbowski, Kulicki & Pugaczewska (1981, fauna & stratigraphy of Late Triassic-Aalenian in Sassendalen); Weitschat & Lehmann (1983, stratigraphy & ammonoids of Middle Triassic); Birkenmajer (1984e, depositional sequence in the De Geerdalen Fm., E. Spitsbergen); Dypvik, Hvoslef, Bjaerke & Finnerud (1985, the Wilhelmoya Fm. at Bohemanflya). Mork et al. 1992, classification and correlation).

Edgeoya and Barentsoya. Pchelina (1977, Permian and Triassic deposits); Flood, Nagy & Winsnes (1971) and Lock, Pickton, Smith, Batten, & Harland (1978), (geology of the islands). There is evidence of volcanism from Muraskov, Pchelina & Semevskiy (1983, Carnian spilitic lava flows) and EI-Kammar & Nysaether (1980) have described the petrography and mineralogy of the phosphatic sediments of Svalbard. Kongs Karls Land. Smith, Harland, Hughes & Pickton (1976, geology of the islands); Worsley & Heintz (1977, stratigraphic significance of Rhaetian marine vertebrate fauna).

Geological maps. Maps (1 : 500 000) Dallmann (1993, sheet 1G, Spitsbergen, S. Part: Winsnes & Worsley (1981, Sheet 2G Edgeoya); Hjelle & Lauritzen (1982, Sheet 3G Spitsbergen, N. part); Lauritzen & Ohta (1984, Sheet 4G Nordaustlandet). Palaeontological studies. Gazdzicki & Trammer (1977, the Sverdrupi zone in Svalbard); Bjaerke & Manum (1977, Mesozoic palynology of Svalbard); Bjaerke (1977, palynology in Kong Karls Land); Birkenmajer & Jerzmanska (1979, shark teeth); Lofaldi & Nagy (1980, foraminiferal stratigraphy on Kongsoya); Korchinskaya (1980, Early Norian fauna, Svalbard); Mazin (1981, a primitive Early Triassic Ichthyosaurus); Wierzbowski, Kulicki & Pugaczewska (1981, fauna & stratigraphy of the Late Triassic-Aalenian of Sassendalen); Smith (1982, Early Norian palynoflora); Vasilevskaya (1987, Late Triassic pteridosperms); Weitschat (1983, Early Triassic ostracodes); Hatleberg & Clark (1984, Early Triassic conodonts). 18.2

Structural frame

Interest is two-fold (i) the inherited and developing framework within which Triassic sedimentation progressed and (ii) the subsequent events which determined the present-day Triassic outcrop: mainly the (Cretaceous) uplift and intrusion of basic sills and dykes and the (Paleogene) West Spitsbergen Orogeny.

The post-Triassic structural frame. Most of the western edge of the basin within the West Spitsbergen Orogen is folded and thrust. In the Festningen section the strata are vertical (and somewhat thrust) and south of this the outcrop is limited to a narrow N N W - S S E tectonized outcrop, so that there is little chance of interpreting facies variations except along the N N W - S S E fold axes. The eastern Triassic outcrops of Sorkapp Land are west of the main fold belt. Triassic strata to the East are relatively flat-lying with only minor folds and thrusts over the Billefjorden and Lomfjorden lineaments. The net effect is that in northern Svalbard there is wide E - W development but further south the outcrop narrows (almost to a line on the map) down the west coast. A further consideration is that this west coast outcrop has, to some extent, been transported eastwards in the Paleogene orogeny, perhaps more in the north west of Isfjorden than further south. Thus any interpretation based on a sedimentary contrast needs to make this allowance. A descriptive framework for Triassic sedimentation. We follow the nomenclature as applied in the foregoing Carboniferous Permian outline (Fig. 18.3). It has the advantage thereby of not prejudging what were the effective depositional controls.

344

CHAPTER 18

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a fault zone bounding the west coast of Sorkapp Land and Wedel Jarlsberg Land. This is the PHBFZ western Sorkapp Land and western Wedel Jarlsberg Land - this is the Hornsund-Sorkapp High a line separating the above from the 'Central Basin' a southerly continuation of the Carbonif erous St Jonsfjorden trough - this is the Western Basin in the north and Southwestern Basin in the south as applied here the Pretender Lineament (discussed below) the Nordfjorden High (this terrane merges southwards into the Central Basin as defined here) the Billefjorden Fault Zone (the Eastern Basin) the Billefjorden trough (the Eastern Basin) the Agardhbukta Lineament relatively stable platform areas with some suggestion of activity along lineament F (the Eastern Platform) Edgeoya-Barentsoya monocline.

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Fig. 18.3. Elements of a Triassic framework illustrating various faults that have been suggested as controlling sedimentation. The continuous or dsahsed lines have no significance other than to distinguish the lines. From west to east: KHFZ, Kongsfjorden Hansbreen Fault Zone; PTL, Pretender lineament; RFF, raudfjorden fault Zone; BBF, Breibogen fault Zone; BFZ, Billefjorden fault Zone; VL, Veteranen Line; LFZ, Lomfjorden fault Zone. The East Svalbard Platform is the whole area east of the convenient but arbitrary Lomfjorden Agardhbukta Lineament. Its parts above see level are geographically defined as Olav V Land, Wilhelmoya, Nordaustlandet, Barentsoya, Edgeoya, Kong Karls Land and Hopen (Chapter 5). The Spitsbergen Basin is the whole of the development west of that line and north of Bellsund. This is divided, as before, by the Billefjorden Fault Zone (BFZ) and the Kongsfjorden-Hansbreen (postulated) Fault Zone (KHFZ). The area east of the BFZ is the Eastern Basin. The whole of the linear western outcrop (or Western Basin) is west of the KHFZ. The area between the BFZ and K H F Z is the Nordfjorden High passing south into the Central Basin. Were it deemed necessary to divide the central Basin then a potential postulated lineament is the extension of a rejuvenated Breibogen Fault Zone which Steel & Worsley (1984) projected to underlie the Central (Tertiary) Basin and emerge at Hamburgbukta. South of Bellsund the situation is more complex. The Paleogene fold and thrust belt of the West Spitsbergen Orogen narrows and passes eastwards away from the coast. Thus the western Sorkapp Land both east and west of the K H F Z flat-lying Triassic strata rest on Mississippian strata west of the K H F Z and directly on deformed Precambrian or Early Paleogene strata east of it as far as the deformation belt. This area is referred to as the Southwest Basin and the strata within the fold belt to the east, the South Central Basin. Parallel to

It is no surprise that the above classification follows the Carboniferous structural pattern, in turn inherited from active Devonian faults. The principal problem seems to be the Pretender Lineament of Mork, Knarud & Worsley (1982) which anticipated that of Welbon & Andresen (1992), whereas Steel & Worsley (1984) extended the Breibogen Fault Zone from the north on a similar line in the south. This latter is a more likely persistent structural feature because of its Early Devonian sinistral strike-slip history. Also relevant, perhaps, is the Central West Spitsbergen Fault Zone (CWFZ) of Harland & Wright (1979), with its postulated southern extension as the Kongsfjorden-Hansbreen Fault Zone (KHFZ) of Harland, Hambrey & Waddams (1993), which was based on significant pre-Carboniferous evidence. The Pretender Lineament was argued (Welbon & Andresen 1992) to be a major lineament in western Spitsbergen. They agreed that its only exposure is at the eponymous mountain where similar Devonian followed by Carboniferous and Permian strata crop out on each side. The visible evidence is consistent with Paleogene activity. Other evidence adduced from further south fits the Kongsfjorden-Hansbreen Fault Zone equally well if not better. An ancient fault (a major terrane boundary) is likely to have more relevance to Carboniferous through Cretaceous time if differential movement be needed. The Billefjorden Fault Zone, another pre-Carboniferous terrane boundary, has already been claimed to have had a marked effect on Mesozoic thicknesses (Harland et al. 1974; Parker 1966). This has been disputed on the grounds that Paleogene tectonic thickening might have the same effect. There is no doubt about the tectonic thickening along the old fault lines, but it is not certain how much of this eliminates the possibility of syndepositional Mesozoic diastrophism. The Agardbukta Lineament further east is a continuation of the Lomfjorden Fault Zone with known Paleogene displacement. That line has been taken as a convenient descriptive boundary between the Central Basin (Chapter 4) and the Eastern Platform (Chapter 5) without arguing any particular geological significance. It seems that the reasoning for making these divisions (e.g. M o r k et al.) was to accommodate their new sedimentological interpretation which is accepted here; but the faults are not necessary nor do the facies maps require such lineaments.

18.3

Triassic rock units

The occurrence and distribution of cover units in Svalbard invites a clear division between Late Paleozoic, Mesozoic and

TRIASSIC HISTORY Early Cenozoic strata. The Mesozoic package (Harland 1973a) is separated clearly both lithologically, and by a Late Permian (Lopingian) hiatus, from the Paleogene strata by disconformity representing another hiatus i.e the whole Late Cretaceous interval. Within this Mesozoic package of formations three groups are recognised: Sassendalen (Griesbachian to mid-Ladinian); Kapp Toscana (mid-Ladinian to Liassic); Adventdalen (Bathonian to Albian). It so happens that the Triassic Period approximates the successions in the Central Basin from the Vardebukta into the Wilhelmoya formations. Possibly, however, the later sedimentation of the Wilhelmoya Formation may have been Liassic. Thus, the Triassic Period is represented in Svalbard by (almost) the whole of the Sassendalen Group and almost all of the of the Kapp Toscana Group. Moreover, the lowest part of the Vardebukta Formation (Sassendalen Group), which is generally covered by float, could be latest Permian (Changxingian) in age (Wignell & Twitchett 1996). The Wilhelmoya Formation (upper of the three formations of the Kapp Toscana Group) spans the Triassic-Jurassic boundary. Because the bulk of the rock, if not the major duration of the formation, is Triassic. The formation is described in this chapter, but will be referred to again in the next. The units named above represented the main development as seen in Isfjorden from Festningen in the west to Sassendalen, and to Storfjorden in the east. However, the scheme did not easily accommodate the sedimentary variations in the south (e.g. Birkenmajer 1977) and the islands of Eastern Svalbard so that additional named units have been added to the scheme. On the other hand the succession in Bjornoya has long been known and the two formations Urd and Skuld easily fit in the Sassendalen and Kapp Toscana groups respectively. The scheme here, as discussed in section 18.1.4 is set out in Fig. 18.4 which combines successions already described in Chapters 4, 5, 9, 10 and 11.

18.3.1

The rock unit scheme

The nomenclature of rock units adopted in this work is the result of a compromise from the many available publications. Figure 18.2 shows the relationship of the scheme here to some earlier ones and Fig. 18.4 shows how the scheme is applied here. Lateral variation of the Sassendalen and Kapp Toscana groups is shown in Fig. 4.9.

The Sassendalen Group.

In 1965 the Sassendalen Group was defined as comprising three formations (Botneheia, Sticky Keep and Vardebukta). Formations are primary and their combination constitutes a group. The three constituent formations were defined from measured sections in the Main Spitsbergen Basin. There is no difficulty in distinguishing the three formations in the original section south of Sassendalen in the east and in the classic Festningen section in the west. However, the upper two are best seen south of Sassendalen and the lower one in the Festningen section. The names were accordingly taken from these localities and depicted throughout Spitsbergen on a fence diagram (Buchan e t al. 1965; Worsley & M o r k 1978; Mork & Worsley 1979) (see Fig. 4.9). At that time little detail was known of the Triassic rocks east of Spitsbergen. A study of the Triassic succession in Barentsoya and Edgeoya in 1969 (Lock et al. 1978) confirmed the tripartite divisions originally published by Falcon and they were named as in that table (Fig. 18.2). The lower division, which is an eastern development of the Sassendalen Group, was named the Barentsoya Formation. It is not obviously divisible there. Because the facies coarsen westwards Mork, Knarud & Worsley (1982), divided the Main Basin by the Pretender Lineament which they depicted as an active fault zone during deposition (their fig. 3a). This fault hypothesis is not now supported by Mork (pets. comm.). They applied a different nomenclature on each side of the line using a name from the south (Bravaisberget) in the west for the Botneheia Formation, a Festningen name

345

(Tvillingodden) for the middle formation, and Vardebukta which was defined from Festningen originally. From the Eastern Platform they extended the Barentsoya Formation westwards to the Pretender Lineament. Mork et al. (p. 344) said of this Barentsoya Formation: 'but it is fairly poorly exposed there. We therefore propose a parastratotype in the Deltadalen/Sticky Keep area in central Spitsbergen where the whole formation is well exposed'. This ignored the 1965 definition of the Sassendalen Group by its three primary formations (Vardebukta, Sticky Keep and Botneheia). The Group also happens to contain the Barentsoya Formation in the east. The merit for these changes depends in part on the significance given to the Pretender Lineament. No evidence was argued for the displacements in their fence diagram (Mork et al. 1982, fig. 3a) based on 13 sections. If these are replotted on a geographical frame there is little difference from the original fence diagram of Buchan et al. based on 30 measured sections. That shows a gradual thickening to the west with no evidence for a fault discontinuity. However, the sections are not close enough to determine this matter either way. Until the alternative is demonstrated we prefer to stick to the original scheme which has priority and is simpler. Moreover it was used effectively for south Spitsbergen in Worsley & Mork (1978, fig. 4) and by them also for the Festningen section (1981). If it is useful there is no objection to multiplying names because they can later be equated; but it is not acceptable to demote the original formations that defined the Sassendalen Group to members of the later-defined Barentsoya Formation in the east. Moreover the implication that the Buchan et al. scheme was somehow originally taken from unpublished work of the Norsk Polarinstitutt (Mork et al. 1982, p. 372) is rejected. The monograph Buchan et al. (1965) was published as a Norsk Polarinstitutt Skrifter based i.a. on 30 sections mostly measured by the authors, with a review of previous work and in discussion with Dr Major and others, whose contributions were acknowledged in the monograph. The recommended scheme and its relation to earlier schemes is shown in Fig. 18.2 and without further discussion it is applied in this work, especially in Fig. 18.4. As for other intervals the Triassic outcrops are placed in their regional context, for convenience in earlier chapters as follows. The Central Basin between K H F Z and LFZ in Chapter 4 Eastern Platform (east of LFZ) in Chapter 5 Western Basin (West of K H F Z and between Kongsfjorden and Bellsund) in Chapter 9 Southern Basin (south of Bellsund) in Chapter 10 Bjornoya and adjacent Barents Shelf in Chapter 11.

The Kapp Toscana Group.

Initially a formation, this unit became a group with the local separation of the Tschermakfjellet Formation at the base from the main body of rock (the De Geerdalen Formation). The Wilhelmoya Formation was defined by Worsley (1973) within the Kapp Toscana Group by dividing the De Geerdalen Formation, so making three instead of two formations in the group. At that time the Brentskardhaugen Bed ('Lias conglomerate') now of established Bathonian age had been included in the Kapp Toscana Group and so in the Wilhelmoya Formation. However, that conglomerate had first been included in the succeeding Adventdalen Group as the basal conglomerate of the Agardhfjellet unit and that position has now been again argued (e.g. Backstr6m & Nagy 1985) and is accepted in this work. The consequence is that the Wilhelmoya Formation, originally including that conglomerate, would now be defined with its upper boundary beneath the Brentskardhaugen Bed. These alternative opinions have persisted because of the interpretation of the 'Lias conglomerate'. Phosphatic concretions with Toarcian and other Liassic fossils are evident but they are contained within a matrix of demonstrable Bathonian age. Therefore the view, adopted here, is that the deposit may be regarded as a basal conglomerate formed largely of eroded concretions of an underlying rock no longer preserved in central Spitsbergen. In Southern Spitsbergen and the Eastern Platform the upper part of the Wilhelmoya Formation contains several beds of similar fossiliferous phosphatic concretions (Krajewski 1992a, b) which has apparently supported the alternative opinion that the Brentskardhaugen Bed in central Spitsbergen is a condensed deposit and so was coeval with the conglomerate layers elsewhere. This debate is likely to continue.

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18.3.2

The Sassendalen Group (Buchan et al. 1965)

The Group, named after a valley in central Spitsbergen where it is well exposed (defined by the three formations: Vardebukta, Sticky Keep and Botneheia) consists of 65-700m (Fig. 18.5) of dominantly shaly marine sediments which have intercalated sandstone and thin limestone. It is more shaly than the Kapp Toscana Group above. There is generally less sandstone, though the sandstone component (largely composed of quartz with only minor feldspar and lithic fragments) increases westwards. Analysis of Late Scythian (Olenekian) strata in Isfjorden by Pchelina (1970a) gave 80-90% quartz, 2-10% feldspar and 1-5% lithic fragments. At first glance, basal Triassic strata appear concordant with underlying Permian. This appearance is partly the result of the Kapp Starostin Formation being exceedingly resistant so that the overlying softer beds generally appear to be locally concordant. Moreover, the Triassic Strata are generally soft and often covered by talus so obscuring the relationship. Garwood & Gregory (1896) first noted that there are small angular relationships, supported later especially in the Hornsund region where the earliest Triassic (Griesbachian) stage is not known, the Dienerian strata lying unconformably, with a basal conglomerate, on pre-Late Permian rocks, i.e. Precambrian and Early Carboniferous (Mork & Worsley 1978). In the extreme south, a thinned Triassic succession rests directly on Precambrian rocks of the H o r n s u n d - S o r k a p p High. On Edgeoya, a marked erosional contact is seen, the basal Triassic beds consisting of reworked Permian glauconitic sands (Worsley & Mork 1979); and on Barentsoya there is an irregular erosive contact between Permian and Triassic rocks (Klubov 1965c, d). There is

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347

evidence that the basal deposits on these islands are diachronous, ranging from Griesbachian to Smithian age, Map 2G (Winsnes & Worsley 1981). There is a conformable contact with the overlying Kapp Toscana Group which is seen in Spitsbergen, Barentsoya, Edgeoya and Bjornoya, although it is not always easy to recognize. It seems to represent a hiatus dated biostratigraphically as mid-Ladinian. The three original formations of the Sassendalen Group although varying laterally in thickness are remarkably persistent as mappable units. Each is an upward-coarsening sequence from shales to sandstones, representing a transgressive phase, followed by deltaic progradation. The proximity of the delta largely determines the thicker successions. The most distinctive feature is the widespread Early Anisian (Mid-Triassic) transgression resulting in the Botneheia bituminous shales and phosphatic nodules.

Central Spitsbergen The Vardebukta Fm, 253.5 m at Vardebukta in the Festningen cliff section (Western Basin), comprises sandstones interbedded with siltstones and shales. In the Eastern Basin the outcrops are somewhat obscured by mountain scree and Mork, Knarud & Worsley (1982) suggested the name Deltadalen for it there. Buchan et al. (1965) distinguished two constituent members. Selmaneset Mbr, 136 m at Selmaneset east of Trygghamna of uniform dark grey, often calcareous silty shales with hard calcareous siltstone interbeds. The unit becomes sandy towards the top with clay ironstone concretions. Rare bivalves, bone fragments and one ammonite were recorded. Siksaken Mbr, 104m at Iskletten, a composite section in Oscar II Land, named for the sharp folds exhibited there, is an easily mapped fossiliferous unit of alternating grey, calcareous siltstones and silty limestones passing upwards into lighter calcarenites and sandstones. The base is at the lowest resistant bed and similarly the top contrasts with the softer shales of the overlying Sticky Keep Fm. The Sticky Keep Fro, 121 m at type section on Vikinghogda, just west of Sticky Keep (west of Sassendalen) in the Eastern Basin, comprises a uniform fossiliferous silt-shale lithology and thickness in Sassendalen, where it is distinguished from the underlying ledge of the more resistent top of the Vardebukta Fm and from the softer Botneheia Fm above its topmost resistent ledge. Two members were distinguished. lskletten Mbr, 154m defined above the Siksaken Member in the Iskletten composite section in Oscar II Land (Western Basin) is the lower shaly part of the formation with interbedded dark grey, often calcareous shaly siltstone and grey green flaggy laminated calcareous siltstone. Grey septarian limestone concretions abound. The member is distinguished between the cliff-forming members below and above. Kaosfjellet Mbr, 76 m, Iskletten type section, is named where the member shows small-scale chevron folding. It is a distinctive cliff-forming marker unit of yellow-brown weathering laminated shaly siltstones, alternating with orange to red-brown fragmented harder calcareous siltstones. The unit is best developed in the Western Basin. Botneheia Fro, 157 m in the type section at Vikinghogda, is well exposed on Botneheia to the east. The formation can be traced throughout Spitsbergen except in Sorkapp Land and not so easily distinguished in the Eastern Platform. It consists of a dark grey shale sequence weathering blue-black and dark grey. The upper shales are papery, laminated and bituminous. They contain large light yellow-weathering concretions of grey silty limestone (Daonellen Kalk of Mojsisovics 1886). They always form a distinctive escarpment ('Escarpment shales' of Gregory 1921, 'oil shale series' of Falcon 1928, "Ptychites beds' of Spath 1921). These merge lower down into softer shales which contain phosphatic nodules, generally less than 2 cm, and weathering blue black. These nodules increase to 50% at the base with occasional reworked horizons. The whole formation is richly fossiliferous with ammonites, bivalves, bone fragments, worm tracks and plant remains. A hard siltstone marker horizon occurs at the top of the formation and may be recognised throughout Svalbard. It may be siliceous or even cherty. It is more resistant than the overlying Kapp Toscana Group strata. The formation is thicker and sandier in the Western Basin at Festningen. Further south at Bravaisberget in Western Nathorst Land (Bellsund) the Formation is 215 m thick. Mork et al. renamed the formation in the Western Basin from that mountain. The above account of the Sassendalen Group (taken from Buchan et al. 1965 unless otherwise stated) refers to the Central Spitsbergen Basin. Exceptional are the successions in South Spitsbergen, Bjornoya and the

348

CHAPTER 18

Eastern Platform into each of which the sequences merge without evident discontinuity. This has entailed some additional nomenclature as follows. South Spitsbergen. Birkenmajer (1977b) proposed a somewhat different scheme for south Spitsbergen. His Torell Land Group included the Sassendalen and Kapp Toscana Gps and, while accepting but enlarging the Vardebukta and Sticky Keep Fms, he introduced his Drevbreen Fm to contain the Botneheia and Tschermakfjellet units as members and he combined the Drevbreen and Sticky Keep Fm in his Storbreen Subgp. At the same time he divided his Vardebukta and the original Botneheia division each into two members. Worsley & Mork (1978) measured eight Triassic sections in south Spitsbergen, along the fold belt, at Kistefjellet and Sorkappoya (but not the flatlying strata of western Sorkapp Land). It is noteworthy that, having previously found that the Buchan et al. scheme of three formations (Vardebukta, Sticky Keep and Botneheia) could be applied through western Svalbard, they applied it also to each of their southern sections and accordingly revised Birkenmajer's to be consistent with the rest of Svalbard so applying it to the sequence throughout; but with the two lower formations combined as 'Lower Triassic'. They adopted Birkenmajer's two units: Somovbreen (upper) and Passhatten (lower) as members of the Botneheia Fm, and reduced Birkenmajer's Vardebukta Fm, so the Skilisen Retzia Limestone is included in the Sticky Keep Fm. They agreed that the Lowest Mbr of the Vardebukta Fm (Urnetoppen) alone does not extend across the Hornsund-Sorkapp High. The Sassendalen Group sequences range from 300 m at Treskelen to 130 m at Kistefjellet (Kistefjellet Fm) which is a marine transgressive sequence of approximately Sticky Keep Fm age. Eastern Platform. In the Eastern Platform, Buchan et al. noted that the Sassendalen Group Formations were less easy to distinguish eastwards and indeed Lock et al. (1978) proposed one undivided Barentseya Formation from Barentsoya and Edgeeya (Falcon's 1928, Oil Shale Series). Similarly in Nordaustlandet the Sassendalen Group is approximately represented by the Svartknausane Formation (120 m), a deposit of distal marine facies. Barentsaya and Edgeoya. Falcon (1928) and Klubov (1965b) each made a tripartite division of the Triassic strata. Two independent groups later worked systematically in the area in 1969. The Norsk Polarinstitutt work was published in 1971 (Flood, Nagy & Winsnes) and the Cambridge work (Lock, Pickton, Smith, Batten & Harland 1978). The second publication, delayed by agreement with the exploration company, was based on data from 120 measured sections. Nevertheless Flood et al. have priority and it was a mistake for Lock et al. to use the nomenclature that they had developed. However, it was not easy to recognize the three Sassendalen Group formations in the two islands and the strata were described as one Barentsoya Formation. Nordaustlandet. Cutbill (CSE) reported 150m of shales that he correlated with the Sassendalen Group. From ammonoids collected by Kulling in 1931 (1932) and identified by Tozer (Tozer & Parker 1968; Tozer 1973) a rich Anisian fauna suggested a Botneheia Formation equivalent. Subsequent Russian work greatly enlarged the knowledge of Triassic faunas. The overlying shaly Kapp Toscana Group rocks have hardly been reported. The sequence of marine shales assemblages spans Late Scythian through Anisian, with the possibility of extending back (to Dienerian) or (less likely) on to Early Ladinian ages. Hopen. The deep well, Hopen-2, suggests that, whereas the Kapp Toscana Group thickens in that direction, the Sassendalen Group thins significantly.

Bjerneya. The geology o f B j o r n o y a was generally investigated along with that o f Spitsbergen before the islands of eastern Svalbard were well k n o w n . It has already been outlined in C h a p t e r 11. These notes are based on a t h o r o u g h revision of the Triassic succession in the island a n d reinforced by palynological studies ( M o r k , Vigran & H o c h u l i 1990). As in the rest of Svalbard the Triassic succession divides naturally into the two groups: Sassendalen and Kapp Toscana as arranged here. This division, applied to the Urd and Skuld formations in Bjornoya, works well with the realization that Spathian, Anisian and probably Ladinian ages are not recorded. The hiatus between ?Capitanian and Triassic may be extended in Bjornoya by the lack of Griesbachian index fossils. Indeed the Sassendalen unit (the Urd Formation) spans only Dienerian & Smithian stages: that is the middle (Nammalian) division of Scythian (Early Triassic). Urd Fro, 65 m. Shales and siltstones form the bulk of the formation with sandstones at the base and a remani6 deposit at the top: the Verdande Bed. Dolomite nodules and beds increase upwards.

The lowermost beds contain abundant reworked phosphate and glauconite grains from the underlying Permian Miseryfjellet Fm. The lower 25 m have yielded no macrofossils. The main part is of grey laminated silty shale with 10-20cm yellow-weathering dolomitic siltstones. Darker coloured facies then characterize the remainder of the formation. In the middle part (25+ m above the base) the ammonoid Euflemingites was identified by Pchelina (1972b) and correlated with Smithian strata elsewhere in Svalbard (e.g. with fish remains in the Sticky Keep Fm). Towards the top the siltstones increase at the expense of shales and dolomitic cement increases to give argillaceous dolostones and dolomitic concretions. Pchelina (1972) reported ?Arctoceras blornstrandi, and a fish fragment (Sauriehthys) typifies the 'Fish Horizons' of Smithian age. Bivalve imprints are common. The Verdande Bed at the top is a thin conglomerate of grey phosphatic nodules (up to 10 cm), resting on a dolostone. No body fossils have been found. The contained clastic grains represent a heterogeneous source and are cemented by microcrystalline phosphate. The nodules contain bivalve fragments, sponge spicules, ostracodes, and Mizzia-like algae. Mineralogical composition differs from that of Middle Triassic nodules in Spitsbergen.

18.3.3

The Kapp Toscana Group

This group is n a m e d after K a p p Toscana, a cape on the south coast of V a n K e u l e n f j o r d e n . The unit was defined by B u c h a n et al. as a formation; it was u p g r a d e d to group status by H a r l a n d et al. (1974) a n d has been generally accepted as a regionally significant unit. It n o w comprises three formations: Tschermakfjellet, D e Geerdalen a n d Wilhelmoya. The group as a whole consists of a variable sequence from 8 m to a b o u t 500 m o f deltaic shallow-marine silty shales with m o r e interbedded, thin to m e d i u m sandstones than in the Sassendalen G r o u p below. The sandstones have a high content of feldspathic a n d lithic material a n d are usually intercalated with the shales in recurrent small- a n d large-scale u p w a r d - c o a r s e n i n g cycles. It is a largely n o n - m a r i n e sequence of fine to m e d i u m grained grey-green plant-bearing sandstones, weathering greenish and brown, laminated to massive, and interbedded with shaly siltstones, sometimes calcareous. In contrast to the underlying group, the group thickens to the east from the S o r k a p p - H o r n s u n d H i g h in the lower two formations, and east o f the Billefjorden Fault. But the main thickening east of that fault characterises the Jurassic units (Fig. 18.6).

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TRIASSIC HISTORY

349

De Geerdalen Formation, 190m. The valley, De Geerdalen, is west of the type section at Botneheia. It consists of alternating grey-green sandstones and sandy shales: The base is marked by the first resistant sandstone above the Tschermakfjellet shales and the top, in most of Spitsbergen, below the 'Lias conglomerate'. Plant remains are fragmented and thin coal seams occur. The De Geerdalen Formation is the piece de rOsistance in Spitsbergen of the Kapp Toscana Group. It is dominanted by sandier non-marine facies whose sedimentary environment is treated in Section 18.6.4. The isopach map of the Kapp Toscana Group is largely a map of this formation. Wilhelmoya Formation Wilhelmoya and Hellwaldfjellet. The island of Wilhelmoya and the mainland section at Hellwaldfjellet, 40 km to the south, are of great interest in spanning the sequence. That is possibly from uppermost Sassendalen horizons at the base, through Tschermakfjellet and De Geerdalen Formations and the Wilhelmoya Formation where it was defined (Worsley 1973). It is followed by an uncertain succession through into Late Jurassic strata (Klubov 1965a) (Fig. 18.7). More detail is available in Chapter 5. Palynological ages were investigated by Smith (1975) and i.a. three preparations indicated a Norian age for the De Geerdalen Formation. Worsley named two members of the Wilhelmoya Formation:

T h e base of the K a p p T o s c a n a G r o u p is sharp, with a conformable shale unit overlying the h a r d e r cliff-forming p h o s p h a t i c shales at the top of the Sassendalen G r o u p . It appears to represent a stratigraphic break. The base is not seen in H o p e n , W i l h e l m o y a and K o n g Karls Land. The top is m a r k e d below the B a t h o n i a n p h o s p h o r i t e nodule bed (absent only in K o n g Karls L a n d ) a basal c o n g l o m e r a t e of the softer n o n - m a r i n e shales of the Jurassic A d v e n t d a l e n G r o u p (see C h a p t e r 19). The d o m i n a n t l y sandy D e Geerdalen F o r m a t i o n is the m a i n unit in the group. In some areas there is a basal shaly f o r m a t i o n , the Tschermakfjellet/Austjokelen F o r m a t i o n . W h e r e present, it grades up into the D e G e e r d a l e n F o r m a t i o n . Spitsbergen The Tsehermakfjellet Formation, 63m at Tschermakfjellet in South Dickson Land, is recognized only in the central and eastern terranes of the Central Basin; it has no sharp western margin. It is made of silty shales to fine-grained sandstones with distinctive small red-weathering cla~ironstone concretions and contains an ammonoid and bivalve fauna.

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n kill

1_15~

n

n

100

1 Arnesodden/Mohhegda

12 Hyrnefjellet

23 Passhatten

2 Austjekeltinden

13 Inner Grenfjorden

24 Revnosa

3 Bohemanflya/Syltoppen 14 Kapp Johannesen 4 Bravaisberget 15 Kapp Koburg

25 S. Holmgardfjellet 26 Smalegga

5 Breikampen

16 Kapp Toscana

27 Somovfjella/Tvitoppane

6 Brentskardhaugen 7 Bungebreen

17 Kistefjellet 18 Knorringfjellet

28 Stormbukta 29 Teistberget

8 Eistraryggen

19 KLikenthalfjellet

30 Tilasberget

9 Festningen 10 Fridtjovhamna

20 Marhegda 21 Mohnbukta

'31 Treskelen SE 32 Tumlingodden

11 Hellwaldfjellet

22 Passet

33 W & E Flowerdalen

~

/18 ~

Strata absent

121 ~

~

46

Location numberand thickness in metres (bold number)

/24 ~

76

Fig. 18.7. Localities and thickness of the Wilhelmoya Formation. Some thickness, including the Brentskardhaugen Bed were used in this compilation (by I. Geddes) so that the values on the map may need to be reduced by 1 m or a little more. The lower boundary in Spitsbergen is not everywhere easy to identify.

350

CHAPTER 18

Tumlingodden Member 60m clays and friable sandstones with coal lenses with lignite.

Bjornbogen Member, 59m clays and siltstones with conglomeratic phosphatic and limestone cherts at base. At the top of the 105 m section at Hellwaldfjellet, about 70 km to the SE, there is a conglomerate (suggested but not confirmed as the Brentskardhaugen Bed). The (lower) Bjornbogen Mbr of the Wilhehnoya Fm with its marine assemblage of bivalves and saurian (plesiosaur) bones correlates well with the Kapp Koberg Mbr in Kongsoya and the Flatsalen Fm of Hopen. Taken together the evidence suggests that these strata are most probably Rhaetian in age. The initial boundary probably being somewhere in the uppermost De Geerdalen Fm and the terminal boundary in the succeeding strata which for the most part are well established as Jurassic (Smith 1975; Smith et al. 1975, 1976; Worsley & Heintz 1977). Although not always easy to decide the boundary, the Wilhelmoya Formation extends widely in Svalbard. Moreover sedimentation continued from ?Norian, through Rhaetian into Liassic time. Mork et al. recognized two members in Spitsbergen: Knorringfjellet and Smalegga. The KnorringfjelletMember is, 20 m thick in the type section at Festningen, where it comprises shales, sandstones and carbonate with, at the base and top, thin polymict conglomerates. The Smalegga Member is 28 m thick in the type section in N. Sorkapp Land. Southwards it is predominantly bioturbated quartzitic sandstones with conglomerates, often phosphatic. Northwards it becomes more shaly and sideritic and merges with the Knorringfjellet Member. Barentsoya and Edgeoya. Lock et al.'s (1978) Kapp Toscana unit names (Edgeoya and Negerfjellet formations) are not applied here. Tschermakfjellet Formation serves as well for Falcon's Purple (Blue and Purple) shales and the De Geerdalen Formation for his Sandstone Group respectively. However, for detailed work sections are described as in that publication and correspond approximately to the fence diagram by Flood, Nagy & Winsnes (1971). The uppermost strata of Edgeoya (above Kvalpynten) could well be Jurassic, but no positive evidence to that effect has been adduced. (Rozycki 1959; Buchan et al. 1965; Winsnes & Worsley 1981; Steel & Worsley 1984). Indeed the Wilhelmoya Formation is not known in these islands. Kong Karis Land. In Svenskoya, Beds 1 and 2 (of Pomecknoi 1899, and of Nathorst (1901) were named by Smith et al. (1976) the Mohnhogda Member, 196+m underlain, but not in exposed contact with the Arnesodden Shale at sea level. In Western Kongsoya is the Sjogrenfjellet Member, 130-235m (Smith et al.). The Kapp Koberg Member was described below this at sea level (possibly obscured by ice in 1969) by Worsley & Heintz (1977). These units are Rhaetian and Rhaeto-Liassic and occur below the Jurassic and Cretaceous units which form the upper parts of the hills (Chapters 5 and 19). The Rhaetian unit is the Kapp Knberg Member of western Kongsoya. It is a marine shale passing up into a sandstone and noted for bones and a plesiosaur skeleton (Worsley & Heintz). Part may correspond to the Arnesodden shale at the bottom of the Svenskoya succession. The Mohnhogda and Sjogrenfjellet members have in common a coarse, loose, porous, multicoloured sand, with few cemented beds and lenses, with rare coal and ironstone horizons and containing fragments of petrified wood. It is almost entirely non-marine. Smith et al. (1976) and Bjaerke, (1977) listed 64 palynomorph forms and 12 dinoflagellates forms. From these studies it seems that ages range from ?Norian, Rhaetian up through Hettangian, Sinemurian and possibly younger. Lofaldli & Nagy (1980) found Early Jurassic foraminifera in the top part of the member.

Hopen. Described in Chapter 5 this linear island comprises the following succession: Kapp Toscana Gp Wilhelmoya Fm Lyngfjellet Mbr Fl~tsalen Mbr Iversenfjellet Formation. Notwithstanding the similarity of the Iversenfjellet Fm and the De Geerdalen Fm, Iversenfjellet is retained against the time when the subsurface succession is fully released for publication. Partly by the accident of exploration for hydrocarbons, Hopen has perhaps become better known biostratigraphically than coeval strata elsewhere in Svalbard and might provide one of the key sections globally for interpreting the Triassic-Jurassic transition. Rhaetian strata are preserved in sequence, and the fossils have been located in measured sections.

In summary, the Wilhelmoya Formation is a complex sedimentological unit, recording possibly latest Norian, certainly Rhaetian and Hettangian to Toarcian events. The Triassic-Jurassic boundary being indefinitely placed somewhere within the upper member where one can be distinguished. Smith et al. (1976), Worsley & Heintz (1977), Bjaerke & Manum (1977) agreed on the similarity of a marine Rhaetian shale facies followed by a continental sandstone passing from Rhaetian to Jurassic in all three areas examined by the same workers, i.e. Wilhelmoya (Worsley 1973; Smith 1975), Kongs Karls Land (Smith et al. 1976; Worsley & Heintz 1977) and Hopen (Worsley 1973; Smith et al. 1975). Combining surface and subsurface information (Hopen-2) the Kapp Toscana Group would amount to more than 1200 m in thickness.

Bjornoya. The Kapp Toscana Gp is represented in Bjornoya by the Skuld Fm which comprises the upper 135 m of the section in the mountain Urd and is characterised by several upward-coarsening sequences from dark grey shales with red-weathering siderite nodules to fine-grained sandstone. The lower 10m (just above the Verdande Bed) is of shale with small siderite nodules. Siltstones and then sandstones increase in abundance upwards in which current activity is indicated by ripples and on which plant debris is abundant. It would appear to be a regressive marine sequence of pro-delta deposits probably lateral to the delta distributaries. The siderite cement may indicate a proximal environment. About 50m up the formation was a 3m long Labyrinthodont amphibian P l a g i o s t e r n u m (first reported and covered for protection by a Cambridge party (Lowy 1949), and later removed to the Paleontological Museum in Oslo (Mork, Vigran & Hochuli 1990).

Barents Sea. Worsley e t al. (1988) outlined a newly defined stratigraphy in the Barents Sea. Because o f a feasible correlation with the Svalbard successions there has been a suggestion to r e n a m e some group and f o r m a t i o n names in Spitsbergen and classify t h e m according to the s u b m a r i n e units ( M o r k pers. comm.). In case such proposals should be developed the units from the H a m m e r f e s t Basin have been included in the stratigraphic glossary and index. If such a c o m b i n e d n o m e n c l a t u r e should be attempted the Svalbard names would generally have priority. At present m u c h of the i n f o r m a t i o n is unpublished.

18.4 18.4.1

Triassic time scale and international correlation The standard international scale

F e w controversial questions r e m a i n regarding an international chronostratic scale. Trias originated in the three-fold division in G e r m a n y following the two-fold P e r m i a n (Dyas). H o w e v e r being mainly o f red beds related to the Variscan orogeny there, it contributes little to international correlation. The m a r i n e sequence, especially in the N o r t h e r n Calcareous Alps of Austria b e c a m e the first marine s t a n d a r d with a z o n a t i o n based on a m m o n o i d s , but in complex tectonic relationships. However the argillaceous facies, especially o f the Arctic (and of British Columbia), p r o v e d to have the best a m m o n o i d sequence and has provided the world s t a n d a r d for correlation (Tozer 1967) unless it be in the I n d i a n subcontinent. Nevertheless, most of the Alpine stage names persisted, but were redefined in b o u n d a r y reference points mainly in the C a n a d i a n Arctic. The Alpine stage Scythian (i.e. Early or Eo-Trias) has been divided in two or three schemes as rich new material for this short interval became available. Russian geologists use I n d u a n and Olenekian. However, the scheme s h o w n in the international c o l u m n is the result (largely accepted) o f Scythian stage divisions. This was largely Tozer's achievement. N o t so, however, his a t t e m p t to elimi-nate R h a e t i a n on the basis o f its very short (?unknown) duration. That has been preserved internationally for the time being. The Svalbard succession comprises largely shales and sandstones and the concretions in the shales are typically rich in a m m o n o i d s so that a m m o n o i d z o n a t i o n (as in Jurassic Europe) has b e c o m e the standard m e a n s o f correlation. This works well for

TRIASSIC HISTORY Harland etal. 1990

Jurassic

She111995

Hettangian

J2

208

208

T% (.9

Mork et al. 1992

Tr2

or) < r~

Rhaetian

(2)

Norian

(13)

Carnian

(12)

Ladinian

(6)

210

210+5

210

223

220+8

223

235

229+5

235

233+4

239.5

241

239+5

241

245

245+5

245

Anisian Spathian t-

(~

Smithian (41

o

Dienerian

t'mr 2 .... q~

Griesbachian Late Permian

92

Changxingian

Fig. 18.8. Triassic time scales.

Early and Middle Triassic time but the De Geerdalen Formation, largely of deltaic sandstones offers little help in precise correlation (Fig. 18.8). A new complication has arisen because the Global Stratigraphic Section and Point (GSSP) is a convention not yet agreed by the Triassic Subcommission of the Commission of Stratigraphy, of the IUGS. Normally the recommendation for the initial boundary of the later division would have precedence over opinions about the terminal point for the earlier division. The latest Permian stage (Changxingian) of the latest Permian epoch or sub-epoch Lopingian that are defined in southeast Asia may in part overlap the Griesbachian stage, so that, from a eastern Tethyan perspective, Otoceras boreale would be Permian. Until a decision has been made as to the position of the GSSP the matter is indeterminate and Triassic is used here in its traditional sense (Tozer 1988). Wignell & Twitchett (1996), as discussed below, identified anoxic facies in the Vardebukta Formation and related this to a biotic extinction event at or near the initial Triassic boundary. That is an opinion independent of the definition of the boundary.

18.4.2

Biostratigraphic correlation

Macrofossils. The entire sequence is now fairly well dated on the basis of bivalves and ammonoids (Tozer & Parker 1968; Mork, Knarud & Worsley 1992; Korchinskaya, 1969, 1970, 1971, 1972a, b, 1973; Ishibashi & Nakazawa 1989; Weitschat & Dagys 1989; M o r k et al. 1992; Campbell 1994). Tozer (1967) and Siberling & Tozer (1968) refined a zonal scheme for the Triassic stages of the North American Arctic. It is to this scheme that reference is made in Fig. 18.9 where it can be seen that a zonal scheme for Svalbard is slowly evolving and is now quite well established for the Smithian and Spathian (Olenekian) stages but as yet is rather sketchy for other stages. The scheme defined in the Canadian Arctic is therefore used for primary reference. (i) The Sassendalen Group is of Griesbachian to Early Ladinian age, with all six stages represented. (ii) The Vardebukta Formation at the base of the Sassendalen Group is of Griesbachian to Dienerian age. This is confirmed by the presence of fossils of the boreale zone in the main basin. The other three zones may well be present because sedimentation at the time seems to have been fairly

351

continuous. In parts of southern Spitsbergen on the Sorkapp-Hornsund High and in Bjornoya (?), the Griesbachian stage is absent (Dienerian strata lie with unconformity on Paleozoic and older rocks). (iii) The Sticky Keep Formation is of Dienerian to Spathian age. In the Kistefjellet Formation of the Sorkapp-Hornsund High, Dienerian to Spathian strata overlie Paleozoic and older rocks. Both the candidus and sverdrupi zones are indicated on Spitsbergen, the latter being confirmed in the west. The tardus and romunderi zones are confirmed in Spitsbergen and the Barentsoya/Edgeoya area. The tardus zone is absent in Bjornoya, where the romunderi zone is overlain unconformably by a nodule horizon which is only 20 cm thick but may be of Anisian and Early Ladinian ages. The subrobustus zone and the pilatus zone are represented by only one Spathian zone in Svalbard which is present in Spitsbergen, Barentsoya, Edgeoya and Nordaustlandet. The Spathian is probably lacking in Bjornoya. (iv) The Botneheia Formation of the Central Basin and the Svartkausane Formation of Nordaustlandet are of Anisian to Early Ladinian age, a period of time probably also represented by the Verdande Bed of Bjornoya which is a condensed sequence only 20cm thick. The caurus zone is confirmed elsewhere and the varium zone indicated. There is no evidence of the deleeni zone, but it is unlikely to be absent as no major breaks in sedimentation are noted. The chischa zone is confirmed in Spitsbergen and Barentsoya/Edgeoya. The Early Ladinian subasperum and poseidon zones are confirmed on Spitsbergen. (v) The Late Ladinian meginae and maclearni zones seem to be absent everywhere, suggesting a mid-Ladinian hiatus which marks the junction of the Kapp Toscana and Sassendalen Groups. The base of the Kapp Toscana Group is marked by the sutherlandi zone. (vi) The Kapp Toscana Group is of Late Ladinian to Liassic age. (vii) The bulk of the marine fauna of the lower part of the Kapp Toscana Group in Svalbard is of Early Carnian age. There are records of a Norian ammonite (Korchinskaya 1973). Younger ammonites are not found until the Brentskardhaugen Bed at the base of the Agardhbukta Formation. In view of the marginal marine to non-marine environments of much of the Kapp Toscana Group, pollen and spores have been extremely valuable for correlation, especially with their wide dispersal largely independent of sedimentary facies. (viii) The Tschermakfjellet Formation is of Late Ladinian to Late Carnian age. (ix) The De Geerdalen Formation extends from Late Ladinian (where no Tschermakfjellet Formation is present) to Norian time. (x) The Skuld Formation contains Late Ladinian sutherlandi zone fossils in its upper half and extends through to the Carnian stage. (xi) The Wilhelmoya Formation extends from the Norian through Rhaetian possibly into Liassic stages. The base had been dated as Rhaetian in age on palynology (Smith 1975; Smith et al. 1975; Bjaerke & Manum 1977), but macrofossils have now indicated a Norian age (Pchelina 1980; Korchinskaja 1980). (xi) The Brentskardhaugen Bed is Bathonian, containing mid-Toarcian, Early Aalenian and Bajocian bivalves and ammonoids in the derived phosphatic nodules (Wierzbowski, Kulicki & Pugaczewska 1981; B/ickstrom & Nagy 1985). It was probably finally laid down during the Bathonian transgression. It is now included, as the basal conglomerate of the Agardhfjellet Formation, in the Adventdalen Group. The Rhaetian Stage has presented a problem (e.g. Smith 1974, 1977, 1986). Continuous marine facies through the Triassic Jurassic boundary are few. The record suggests that the Triassic ammonoids were almost extinct before the advent of the new Jurassic stock, beginning notably with Psiloceras planorbis which clearly marks the initial Hettangian stage. The difficulty lies in distinguishing Norian from Rhaetien, if ammonoids are the index fossils. The original Rh/itische Gruppe in the eastern Alps of Europe was based not on fossils, but on a lithostratigraphic unit. Only in 1975 was the palynostratigraphy of this Austrian unit described by S. J. Morbey in 1975 (Smith 1977). This work established the stage in positive characters of a largely non-marine flora. Rhabdoceras suessi is the latest Norian zonal ammonite and Choristoceras marshi is exclusively Rhaetian, but is of very limited occurrence, as indeed is Sirenites from Hopen which is one of only four localities (others are Austria, British Columbia, Nevada and California) where Rhaetian ammonoids have been recorded; but no Norian ammonoids are known from Svalbard, nor are good Norian palynofloras known from Norian ammonitic facies. Figure 18.10 summarizes the Triassic stratigraphy of Svalbard.

352

C H A P T E R 18 ,-.4

=

o

[..,...

o

~Z o

6 r.~ C~

5,

.,,,~ == oo 0o o (,.q

I

KAPP TOSCANA a~ -~ 9.o

SASSENDALEN

GROUP* [\ \ \

I I

\

GROUP*

J"

.,.., v.

8-

I

N

[..O

>,E _~u_

~~,E, o rn

's

=o

o

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o

r.13

_>, ".,=

._ Z

I I I LATE TRIASSIC

_,-

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MIDDLE TRIASSIC

TRIASSIC

I I ] .~ -~

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p=

co Z

SCYTHIAN (EARLY TRIASSIC)

.,,,~ (.9

,,-,,

TRIASSIC HISTORY

Timescale

Bjorn~ya

I

J

Hornsund High I

SW

Main Basin

Barentseya Edgeeya

Brentskaudhauge~~

Post-Triassic

353

"~//~/' w ~

Wilhelmoya Fm.

Rhaetian

Kong Karls Land Svensk~ya Kongsoya

Wilhelmoya OVL / NA

Hopen

i

M~hnh~gda sst ! ~ E9 Sj~gronMbr. ~ ,, fjellet sst w Wilhelmoya Arnesodden I ~ ~ Mbr. Fm. shale Bed

Ne~i~e"et]

,

Ulaneset Fm.

.. ~~

Lyngefjellet Fm.

55~ o-~

Flatsalen Fm.

n, 0 <

Norian

De Geerdalen Fm. 185 m

De Geerdalen Fm. 190 m

Camian

Edgeeya Skuld Fm.

Ladinian

(Bravaisberget Fm.)

~"

Spathian

~

-9 ~-

7~ m

mO O

--

Z

Botneheia Fm. 160 m

O O

Kaosfjellet Mbr. 122 rn

"o "~

.~ Smithian --EE

Z fjellet Fm. g0 rn

Austkjokelen Fm. (originally Tschermakfjellet Fm.) 40 rn

Anisian

Fm.!

Iversenfjellet Frn. 325 m

Sticky Keep Fm. Iskletten Mbr. 110.5

garentseya Fm

Siksaken Mbr.

Dienerian

==

Vardebukta Fro. (Deltadalen Fm.) Griesbachian

Pre-Triassic

Selmaneset Mbr.

Miseryfjellet Fro.

Fig. 18.10. Stratigraphic correlation chart. Vertical ruling indicates a stratigraphic hiatus; diagonal ruling indicates lack of data because not seen below or not known above the topographic surface, with known limits of strata defined by a dashed line.

18.4.3

Magnetostratigraphic correlation

Hounslow et al. (1996) described an investigation into the polarity (normal-reversed) sequence of the Vardebukta and lower part of the Sticky Keep formations in the Deltadalen sections, with over 12 divisions. An attempt was made to correlate with a more complete sequence in the Sverdrup Basin. No orientation or palaeolatitude data were recorded.

18.5

Triassic biotas

The Triassic biota of Svalbard includes, sponges, foraminifers, bryozoans, brachiopods, gastropods, bivalves, nautitiloids, ammonoids, crinoids, echinoids, ostracodes, decapods, conodonts, fish, marine reptile remains, plant fossils (palynomorphs), and trace fossils. Nevertheless, many occurrences such as shell beds are monospecific (Campbell 1994, p. 33). The dominantly argillaceous marine or deltaic environments contrast with those of the Pennsylvanian and Permian shelf carbonates, dolostones and evaporites. There are, thus, facies differences as well as an evolutionary development. This in part stems from a major change from hot dry to temperate wet climates which reflect the increased northward change of latitude. Shales with molluscs (ammonoids and bivalves) and vertebrates (fish and saurians) are typical and replace the common Permian marine macro-biota of brachiopods, corals, fusulines and bryozoans. Land floras are known mainly from palynomorphs and are best developed in the non-marine late Triassic facies where there are occasional thin coal seams; but the Triassic flora is not as well known as the Mississippian flora of Svalbard.

18.5.1

Vertebrates

Fossil vertebrates were often the prime target of early expeditions to be followed by thorough laboratory work. However, for a long time the stratigraphic positions were recorded only in terms of fossil beds. For Triassic vertebrates Wiman (1910) listed three in particular: Upper Saurian Niveau (in Tschermakfjellet Formation); Lower Saurian Niveau (top of upper member of Sticky Keep Formation); Fish Niveau (middle of lower member of Sticky Keep Formation). Little more was done stratigraphically after the Festningen profile survey of Hoel & Orvin (1937) until a systematic attempt by Buchan et al. (1965) to set up a lithostratic scheme and list recorded Triassic fossils and their localities. The Cambridge field parties did not include vertebrate specialists, but in the course of identifying the 850 specimens (mainly from later seasons) as mostly plesiosaur, ichthiosaur, plagiosaur material, with few identifiable fish, Cox & Smith (1973) listed systematically all recorded Triassic vertebrates. Omitting discussion of synonymies, a simplified list, more nearly in contemporary nomenclature, is given below. All the fish, all the amphibians except the Plagiosaurida, and the Omphalosauridae were from the Sticky Keep Formation, i.e. late Scythian (Smithian and Spathian). The remainder, namely the Plagiosauridae, the Mixosauridae, the Shastasauridae, sundry other ichthyosaurs, and all the plesiosaurs are from the Kapp Toscana Group, i.e. Late Ladinian through Rhaetian. This may have little significance except for the change from marine to largely continental environments.

354 Sub-class Chondrichthyes Infra-class Elasmobranchii Order Selachii Family Hybodontidae Acrodus Hybodus Palaeobates Polyacrodus Sub-class Osteichthyes Infra-class Actinopterygii Super-order Chondrostei Order Palaeonisciformes Sub-order Palaeoniscoidea Acrorhabdus Birgeria Boreosomus Pteronisculus Pygopterus Sub-order Platysomoidei Babastraura Order Perleidiformes Perleidus Order Acipenseriformes Saurichthys Incertae sedis Semionotus Infra-class Crossopterygii Super-order Actinistia Axelia Mylacanthus Sassenia Scleracanthus Wimania Infra-class Dipnoi Family Ceratodontidae Ceratodus Class Amphibia Sub-class Labyrithodontia Order Temnospondyli Sub-order Rhachitomi Super-family Trematosauridea Family Trematosaurida Aphaneramma L yrocephalus Platystega Tertrema Family Rytidosteidae Peltostega Sub-order Stereospondyli Super-family Capitosauroidea gen. et sp. indeterminate are 'Cyclotosaurus' 'Sassenisaurus" 'Parotosaurus' "Capitosaurus' Superfamily Brachyopoidea Family Brachyopidae Ooreosaurus Sub-order Plagiosauria Family Plagiosauridae Plagiosternum ?Plagiosuchus Class Reptilia Sub-class Ichthyopterygia Order Ichthyosauria Family Mixosauridae Mixosaurus Family Omphalosauridae Omphalosaurus Grippia Family Shastosauridae Pessosaurus Family, gem et sp. indet "Ichthyosaurus'

CHAPTER 18 Sub-class Eurapsida Order Sauropterygia Sub-order Pleisosauria Family, gen et sp. indet-vertebra

18.5.2

Conodonts

Conodonts generally depend on carbonate facies for profitable investigation so the Triassic rocks of Svalbard are not promising. Moreover, where correlation help is needed the facies are not propitious. So it is that successfully identified occurrences confirm what was already known regarding age. For example Arctoceras beds include Neogondolella milleri, N. planata, N. nevadenis, N.jubata and Neospathoides (Weitschat & Lehmann 1978). Perhaps more use are the conodonts from Otoceras beds (Dagis & Korchinskaya 1987). In any case the ranges of many conodont families that survived the end Permian crisis, terminate during Triassic time and only three continue to Cretaceous time. Nakazawa et al. (1990) reported that the Sticky Keep Formation, south of Van Keulenfjorden, is characterised by Smithian and Spathian conodonts including at least five species of Neogondolella. Nakrem & Mork (1991) worked on material from the Vardebukta Formation and discussed other Triassic records. All appeared to be Dienerian to Smithian with other species of Neogondolella and Neospathodus. Other contributions include: Birkenmajer & Trammer (1975) and Dagys & Korchinskaya (1989).

18.5.3

Molluscan faunas

Molluscan faunas dominate Triassic marine facies and have provided the principal means for macrofossil zonation, which is indeed more discriminating than is yet possible from microbiotas. This is largely because the distinct ceratite ammonoid evolution, which replaced the Paleozoic goniatites, diversified enormously throughout Triassic time until the Rhaetian stage. Then after near extinction the remarkable Jurassic-Cretaceous ammonite diversification took their place. Although the term ammonite is often used loosely for all Mesozoic ammonoids, the true ammonites are largely restricted to Jurassic and Cretaceous time. The term ceratite is more appropriate because of its distinctive suture, but is not entirely satisfactory. Lehmann (1981) regarded mesoammonoid as a more accurate term; but ammonoid is used here. Bivalves provide the other element. Mojsisovics von Mojsvar (1874) first decribed Daonella and Halobia. They are numerous in individuals, but not in species and are a useful supplement in zonal biostratigraphy. Being of flatter configuration than ammonites they can often be identified in fine shales where ammonoids are flattened. From this point of view they also have the advantage of calcite rather than aragonite shells and so have a better chance of preservation. On the other hand the characters by which species are discriminated are fewer and more subtle. A recent monograph on Daonella and Haloboidea (Campbell 1994), gave a picture i.a. of Svalbard Haloboidea which may be typical of other thin-shelled bivalves such as Posidonia claraia. The halobiids are represented in Svalbard by only 8 species. Ammonoids were undoubtedly free of attachment whether free swimming, drifting or crawling; but the halobiids from their morphology are known to have been byssally attached to some substrate- floating or growing from the sea floor. Yet, like the ammonoids, they were widespread (cosmopolitan) and so have their value in correlation. This would appear to be a problem for an attached organism. The explanation must be that the larvae were planktonic or free swimming before adventitious attachment to any available object. Halobia almost certainly evolved from Daonella, but the phylogeny of the earlier bivalves is uncertain (Campbell 1994). The following account summarizes the sequence of molluscan faunas in Svalbard and the zonal scheme is shown in Fig. 18.9. It is

TRIASSIC HISTORY necessarily based on the a m m o n o i d zonal f r a m e w o r k and follows Tozer's (1967) s t a n d a r d for Triassic time and modified only slightly since (e.g. Tozer 1988). The deficiencies of the original Alpine Triassic stages (facies and structural difficulties) led to the s t a n d a r d being best developed in the Arctic m a r i n e shaly facies ( C a n a d i a n , Svalbard and Russian supplemented by British Columbia. The standard was therefore largely C a n a d i a n but Tozer was able to check the identification of C a m b r i d g e material (Tozer & P a r k e r 1968) and review the succession in Svalbard. K o r c h i n s k a y a in a series of papers (1969 to 1989) provided the correlation between Svalbard and the Russian Arctic: The resulting 31 zones are of p r o v e n international value. F r o m a Svalbard perspective correlation studies by Ishibashi & N a k a z a w a (1989) a n d Weitschat & Dagys (1989) supplemented that correlation and their conclusions were placed in a global bivalve context by Campbell (1994). Early Triassic molluscs. Griesbachian and Dienerian, i.e. the Early Scythian or 'Alteren Eotrias' of Frebold (1939), and Induan of the Russian Arctic. Otoceras though not common has been recorded from the base of the Vardebukta Formation and confirms the boreale zone of Early Greisbachian (e.g. Nakazawa, Nakamura & Kimura 1987). Claraia stachei of (Late Griesbachian) has also been recorded in the Vardebukta Fro. (commune through strigatus zones). Four species, Proptychites (including a possible P. strigatus) may indicate Late Griesbachian or Dienerian. No Dienerian ammonites were recorded but Pseudomonotis cf. multiformis may indicate the Sverdrupi zone (Late Dienerian Myalina similarly indicates Griesbachian or Dienerian. There may be a hiatus representing latest Dienerian time (i.e. between the Vardebukta and Sticky Keep Formations). Smithian (=Early Olenekian of Russian Arctic) Arctoceras, Xenoceltites, Prosphingites spathi and Posidonia mimer with Pseudomonotis occidentalis is a well established fauna from the 'Posidonomya beds' or Fish Niveau of the lower Sticky Keep Formation. This assemblage combines a lower one (romunderi zone) characterized by Euflemingites romunderi and Arctoceras blomstrandi, and an upper one (Wasatchites tardus zone) contains several other ammonite species including Arctoprionites and the bivalve Pseudomonotis. This rich assemblage in the lower Sticky Keep Formation has been fully investigated (Weitschat & Lehmann 1978). Spathiau (=Late Olenekian). This stage is identified in Svalbard by Svalbardiceras spitzbergense, Keyserlingites subrobustus and Posidonia aranea. This is the older Grippia Niveau and Untersaurier Niveau. it occurs at the top of the Sticky Keep Formation. Most if not all of the Svalbard material fits the Late Spathian subrobustus zone. The earlier Pilaticus zone is not recognized in Svalbard but the subrobustus zone has a rich ammonoid fauna (Weitschat & Dagis 1989). Middle Triassic molluscs. Anisian. Three, and probably all four, Canadian zones, well represented in Spitsbergen by distinct assemblages, are restricted to the Botneheia Formation. The lower boundaries practically coincide. The Lenotropites caurus zone fossil is present with at least ten other ammonite species but mainly restricted to Walbergoya in Hinlopenstretet (Korchinskaya 1982). The middle fauna, also rich in ammonite species records Anagymnotoceras cf. varium for that zone; but while individual fossils are common, localities with identifiable material are rare. This assemblage was first collected by Kulling in 1931 in Nordaustlandet, and Tozer & Parker (1968) included Anagymnotoceras or Hollandites spp., Stenopopanoceras sp., Ptychites and Japonites. Daonella (dubia) liadstroemi appears above the varium zone and, if correlated with the appearance of Daonella (dubia) in Canada, the deleeni zone is represented. However, the third rich assemblage is the fourth Chischa Anisian zone with abundant ammonites of several species and many are identifiable in layers of concretions. Frechites laqueatum is characteristic of this zone as also species of Gymnotoceras and Parapopanoceras. A detailed description of late Anisian to early Ladinian ammonoids (figured) from the Botneheia Formation was reported by Weitschat & Lehmann (1983). These daonella shales (Botneheia Formation) permit the distinction of three ammonoid zones: Late Anisian: Frechites laqueatus; Early Ladinian Tsvetkovites varius followed by Indigerites tozeri. Ladiniau. The Daonella Niveau characterizes these rocks and perhaps marks the initial Ladinian boundary with bituminous siltstones and phosphatised mudstones. Korchinskaya (1982) identified two assemblages.

355

The earlier is marked by the Daonella shell beds (D. degeeri), with Ptychites nanuk, P. svetkovites and others, and belongs to the subasperum zone. The later assemblage is rich in Nathorstites species, Arctoptychites popowi, several other ammonite species and Daonella subarctica, D. frami, D. degeeri, D. lommeli and other bivalves. The occurrence of A. popowi suggests correlation with the Poseidon zone. Thus, the two early Ladinian zones are well represented. They conclude the range of Daonella and this practically coincides with the upper part of the Botneheia Formation. Late Ladinian faunas may not be present and so represent a significant hiatus in Svalbard noticeable between the Sassendalen and Kapp Toscana Groups. Late Triassic molluscs. The Kapp Toscana group is not so rich as before in marine facies except for the basal Tschermakfjellet Formation. Carnian. The shales, with sideritic nodules, extend throughout much of Svalbard and the nodules contain predominantly Halobia zitteli and Nathorstites of which there are at least three species plus Sirenites, Dawsonites, nautiloid fragments, gastropods, brachiopods etc. Whereas Halobia zitteli indicates Carnian age, Nathorstites is typically Ladinian in Canada but both are associated in Russia as well as Svalbard. The conclusion to this appears to be (Campbell 1994) that H. zitteli represents the two Early Carnian zones: desatopyense and obesum; Nathorstites has a more extended range than first thought. The beds above H. zitteli are largely non-marine, probably Carnian and most fossils, not age-diagnostic, include brachiopods Retzia, Spiriferina and Lingula. A number of bivalve genera, e.g. Trigonia, Lima, Myophoria, Chlamys and rare Halobia also gastropods and echinoderm fragments. Norian. Although it is likely that much of the De Geerdalen Formation is Norian there are few age-specific fossils. Fossils are generally found in sideritic concretions with few ammonoid species such as Pterosirenites nelgechensis and common bivalves with Halobia aotii etc and Oxytoma. Pterosirenites is typical of the kerri zone in British Columbia and in the Early Norian of northeast Russia.

18.5.4

Bryozoans

B r y o z o a n taxa divide into three stratigraphic groups of which one ranges f r o m Arenig t h r o u g h P e r m i a n with some C r y p t o s t o m a t a and T r e p t o s t o m a t a surviving into Scythian time. Of the other two groups one ranges Cretaceous to H o l o c e n e and the other of uncertain affinity m a y range O r d o v i c i a n t h r o u g h Holocene. Svalbard provides one of the few areas with a t r e p t o s t o m e record. Early Triassic bryozoans from m a n y Spitsbergen collections were described and discussed by N a k r e m & M o r k (1991) a n d new species were described. In contrast to the rich P e r m i a n b r y o z o a n f a u n a the species r e c o r d e d were all attributed to the genus Paralioclema. Associated c o n o d o n t s and molluscs d e t e r m i n e d the age as D i e n e r i a n t h r o u g h m i d d l e Smithian; see also N a k r e m (1994).

18.5.5

Flora

Maeroflora. G o o d floras, including tree trunks (i.e in K o n g Karls Land), have been obtained from a n u m b e r of horizons earlier investigated by N a t h o r s t and colleagues. Their exact location is not k n o w n . Silicified segments of g y m n o s p e r m trunks could have slipped from horizons above the R h a e t i a n sands in K o n g Karls Land. M o s t plant remains are indeterminate so that the only indication of the succession of Triassic land floras comes f r o m palynomorphs.

Palynoflora. Early contributions include K o r o t k e v i c h (1969) f r o m Spitsbergen a n d Smith (1974 et seq.) a n d Bjaerke (1975) f r o m H o p e n . M o r k , Vigran & H o c h u l i (1990) reported as follows. Early Triassic trilete caveate spores belong to a specialised group of pteridophytes, and these tended to be replaced by lycopsids (with caveate monolete spores). In these developments, Svalbard (and the Arctic generally) were in advance of more southerly floras probably because of the more humid temperate climates that prevailed. This humid environment

356

CHAPTER 18

is confirmed by the occurrence in the Urd Formation of fungal hyphae (Hochuli, Colin & Vigran 1989). The Late Ladinian of the Skuld Formation assemblages are distinguished by the abundance and variety of gymnosperm pollen. A number of new Carnian forms come in. Pteridophyte spores, which increase in abundance around the labyrinthodont bed, suggested proximity to a shore with luxuriant vegetation.

Palynomorph sequence from Barents S h e l l

A study of the Triassic succession in terms of palynomorphs throughout the Barents shelf was undertaken by Hochuli, Colin & Vigran (1989) who recognized lettered assemblages A to P . Of these only five assemblages applied to Bjornoya (Mork, Vigran & Hochuli 1990). C Middle Carnian D Early Carnian G Late Ladinian N Smithian O Dienerian Mork et al. (1990, fig. 13) plotted a Triassic correlation chart extending from Svalbard, through the submarine Barents Sea and through Arctic Russia based palynologically.

18.5.6

The Rhaetian problem

Our geological forebears identified intervals or revolutions separating the chapters of Earth history with remarkable prescience. The Triassic-Jurassic boundary is no exception as the ceratitid ammonoids became extinct and before the phylloceratid and other Jurassic ammonites had developed widely. Smith (Smith et al. 1975) remarked that the problem in correlating the upper Hopen strata was not so much lack of fossils as lack of international standards with which to correlate. However, the Hopen facies are dominantly continental and the marine incursion may not have had global connexions. Partly because of the lack of good international index fossils there has been continuing debate even as to the usefulness of a Rhaetian interval. Harland et al. (1990), in giving it an arbitrary duration of 2 million years (210-208Ma), had little stratigraphic basis and it was in part a protest against the all-consuming Norian stage of some authors. Therefore, once again we may look to Svalbard to throw some light on international stratigraphy. The biota as quoted from the Flatsalen Member comprises the following. Ammonoids: a few specimens only of probably one genus Sirenites. The Arctosirenites reported by Flood et al. (1982) typical of Carnian faunas may have been misidentified. In any case Sirenites does not easily correlate - it may be a relict fauna. Bivalves: The Haloboidea (Campbell 1994) include the reported finding of Halobia zitteli by Flood et al. (1971b). Halobia-type fossils are not uncommon, but are difficult to identify specifically without excellent material. Halobia zitteli is typically Carnian and may be incorrectly named. Pchelina quoted Anodontophora cf. ovalis of probable Norian age. Uncertain identifications of Gryphaea and Panopaea are not sufficient for age determination. Crustaeea: Pchelina (1972b) from her Norian divisions I & II (well down into the Iversenfjellet Mbr reported Estheria minuta, Pseudestheria ovata and Howellites princetonensis which are characteristic of Zechstein (German Keuper and American late Triassic). Vertebrates: Only one ichthyosaur was found 30-40 m above the base of the Flatsalen Member and the age is only determined by its position there (Cox & Smith 1973). Plant megafossils: Pterophyllum of uncertain locality probably can only be Late Jurassic as also Protojuniperoxyleon arcticum sp.nov. (Selling 1944) should be erased (Selling 1951) because it was probably a bennettitalian. It was associated with the spore Triletes but from a loose block. Pchelina (1972a) recorded from the lower part of the Iversenfjellet Member (her Carnian) Pterophyllum, Protophyllun, Glossophyllum, Paratatarina, Taeniopteris, Ginkgo and Desmiophyllun. These help little with the correlation problem.

Palynomorphs. On the other hand D.G. Smith (Smith, Harland & Hughes 1975) made a thorough palynological study of material collected systematically. Grey siltstones were most productive, coal samples yielded little. As elsewhere in Svalbard the most promising material is often singularly disappointing and the reasons have been discussed (Hughes, Harland & Smith 1976; Manum et al. 1977). Nevertheless substantial progress has been made and 30 taxa were listed first for their internationally known distribution stage by stage, emphasizing those from the type successions and also according to their stratigraphic occurrence through the Hopen succession. Smith's conclusions (Smith et al. 1975, p. 18) are that the Hopen flora as a whole is consistent with Late Triassic to Early Jurassic age, and there is a regular change up the succession with no significant break. Even the lowest samples could be post-Carnian so that the Carnian-Norian boundary in Hopen is probably lower than Pchelina indicated. The presence in the Flatsalen Member of probable Rhaetogonyaulex rhaetica, cf. Kyrtomisporis speciosus, Camarozonosporites laevigatus, and the first appearance of Classopolis 'almost certainly signals a Rhaetian age' for these beds. In the uppermost sample from the Iversenfjellet Member Kyrtomisporis, Chasmatosporites and the lowest probable Cerebropollinites suggest that this part of the section is also Rhaetian. A tentative Norian-Rhaetian boundary might be 100m down into the Iversenfjellet Member. In the highest samples a few palynomorphs considered to be Early Jurassic appear (Granulatisporites subgranulosus, Polycingulatisporites circulus and rare Heliosporites reissingeri and this suggests that the Rhaetian-Hettangian boundary is within the Lyngefjellet Member). Generally the Flatsalen flora has less than 15% in number of individuals of marine microplankton (acritarchs) so that the dominant flora is non-marine.

18.6

Sequence of Triassic environments

Following the Lopingian or longer gap in the stratal record, latest Permian slight warping of the Tempelfjorden Group provided a stable platform for Triassic sedimentation in a quite new setting. Comprehensive sedimentological interpretation was provided by Mork, Knarud & Worsley (1982) and the sedimentological conclusions in the following account depend on that source. They confirm the original division of the succession into formations and especially the contrasts between the Sassendalen and Kapp Toscana groups. A Triassic fence diagram depicts Triassic stratigraphy (Fig. 4.9).

18.6.1

Early Scythian (Griesbachian and Dienerian--lnduan of Russia)

The Vardebukta Formation, to which the above interval approximates, contains some Griesbachian marine fossils so establishing an Early Scythian marine incursion. It cannot be established how much of earlier Griesbachian time is not represented nor is the fossil record good enough to say whether the transgression was more or less synchronous. Dienerian faunas are better represented. The formation represents a coarsening-upward cycle indicating a deltaic invasion from the west towards a muddy marine environment. This situation is reflected in the greater thicknesses in the western basin from about 100m in the centre and east to about 200 m, reaching 300 m in the centre west but thinning southwards to less than 100m in the Hornsund area. It certainly thins to the northeast of Svalbard and is not known above sea level in most of Eastern Svalbard. Wignell & Twitchett (1996) reinterpreted the environment of formation of lower Vardebukta strata as one of anoxia. The evidence being that 6 m up from the base, bioturbation, manifest below, is not evident for the next 60 m. The sediments are finely laminated, framboidal pyrite is abundant and articulated fish

TRIASSIC HISTORY

357

skeletons are preserved intact. The bedding surfaces may also preserve Claraia and other bivalves with rare Planolites burrows. This interpreted anoxic episode appears to be independent of the changing depth of water in a shallowing-upward sequence. The authors refer this Spitsbergen eposode to a global oceanic anoxia related to the Permo-Triassic biotic crisis. In Spitsbergen it would be post or syn-Otoceras boreale. Whether it marks the Permo-Triassic boundary must await an international decision on the precise location of a GSSP. Gramberg (1959), Gruszcynski & Malkowski (1987) and Gramberg, Krasil'shchikov & Semevskiy (1990) may have been working along similar lines in northern Russia. In south Spitsbergen strata thin more steeply over the Hornsund High which received marine sediments unconformably on Permian or older rocks in a latest Greisbachian or Dienerian transgression depositing the Kistefjellet Formation. It begins with an unusual basal conglomerate and deposition continued through the remainder of early Scythian time. Vardebukta Formation transgression reflects initial stormy sedimentation with transport towards the east and southeast. Barrier sands of deltaic origin allowed lagoons to develop shorewards. The environment of deposition was of a distal marine shelf accumulating mud, silts and occasional sands which are often disturbed by storm-generated currents. The sediment source and greater thickness in the west are evidence of a marginal deltaic front prograding into the shelf sea. At the northeast corner of Barentsoya and in central Edgeoya Permian (Tempelfjorden Group) inliers show an eroded and pitted unconformity surface beneath the Early Triassic strata whose age is not known precisely. In the northwest beneath the Ny-Alesund Paleogene coal deposits is the Bottom Shale of Orvin (1934). This thins from 50 m in the SE to zero in the NW the overlying strata being removed before the Paleogene deposition. Challinor (1967) correlated this lithostratigraphy with the Vardebukta Formation. The late Cretaceous tilting and erosion probably removed all (younger) Triassic deposition to the north of the main Basin so we are ignorant of the facies distribution there except that to the north was probably a Triassic land area.

18.6.2

Later Scythian (Smithian and Spathian = Olenekian of Russia)

The Sticky Keep Formation approximates to, and roughly provides the evidence for, this interval. Distal marine shales formed in the centre and east. A rich fauna of molluscs (mainly ammonoids and bivalves), fish and saurians inhabited the seas which continued to reflect a distal marine environment in relation to a proximal encroaching delta in the west. The greater thickness and sandstones facies led Mork, Knarud & Worsley (1982) to give another name to the formation (Tvillingodden) in the west which may be regarded as a facies varient or member of the Sticky Keep Formation. This unit also provides evidence of an upward-coarsening sequence, best seen in the west. Scythian palaeogeography is postulated in Fig. 18.11 a. Disturbance of sedimentation by storm action is seen in the sandy incursions from the west and in the muddy environment of the shelf sea by the narrowing and concentration of mostly phosphatic nodules forming in the mud. There are also larger calcareous concretions rich in fossils and often septarian. Shallow seas are indicated by some oolites. Burrowing organisms and some bioturbation are also evident. M o r k et al. postulated a complex model of barrier bar progradation with development of barrier sands, tidal inlets and lagoon systems at Festningen and in the west. Desiccation cracks show that the succession was formed near sea level. Differential subsidence is evident in thickness variations of the Sticky Keep Formation over the Billefjorden Fault zone with some downwarping to the east, and there is some thickening (?at this time) over the Lomfjorden-Agardhfjellet Lineament. The Urd Formation of Bjornoya is of Dienerian and Smithian age and has much in common with the above. The Verdande Bed,

Fig. 18.11. (a) Early, (b) Mid- (early Ladinian) and (c) Late Triassic sedimentary facies of Spitsbergen, Barentsoya and Edgeoya as adapted from Mork, Knarud & Worsley (1982, figs 42A, 43A and 44A).

at the top, is a condensed deposit of phosphate nodules. This also marks a hiatus corresponding to the Spathian-Anisian interval. Bjornoya is, thus, somewhat out of phase with the rest of Svalbard.

358

18.6.3

CHAPTER 18

Mid-Triassic (Anisian and Early Ladinian)

Evidence for this interval depends on the distinctive Botneheia Formation. This interpretation continues from M o r k et al. (1982). Major early Anisian transgression resulted in dark phosphatic shales in the Central and Eastern basins and the usual sandier deposition in the west where the succession may be twice as thick as in the centre and east. This is evidence of proximity to a landmass supplying a coastal delta system. It is the third major coarsening-upward sequence, seen best in the west. Also again this concentration of nodules appears as basal lags resulting from storm action stirring the waters below wave base. Oolites may indicate bars or shoals. Within the Central Basin the Botneheia Formation, especially, developed anoxic bottom conditions. Burrowing becomes evident upwards with coarser facies. This environment provided perhaps the best potential hydrocarbon source material in Svalbard, as was noted for the Barentsoya Formation in Edgeoya by Falcon's (1928) Oil Shales. Land-based kerogen is richer towards the source in the west but marine kerogen increases eastwards with TOC values up to 11% (Mork et al. 1982). However, the succession in the Eastern Platform indicates increasing evidence of easterly source of sediment as shown in the facies map (Fig. 18.11 b) from M o r k et al. Thus, there was a lagoon or deeper marine shelf extending north and south, but limited to east and west by sediment sources, presumably land. These sandier rocks in the west are mature and well sorted. The coarsest facies are seen in the southwest and south near Sorkapp where on the S o r k a p p - H o r n s u n d High, delta-front sandstones and conglomerates encroach. Cross-bedding suggests a N - S shoreline with sediment transport to the east and southeast. The Skuld Formation of Bjornoya is different from the rest of Svalbard in that it is of Ladinian and Early Carnian age and thus spans the Sassendalen/Kapp Toscana break. The postulated (Pretender) fault (Mork, Knarud & Worsley 1982) as a boundary between the coarser facies of the Sassendalen Group to the west, is not favoured here as discussed below. The thickening westwards, with more sandy facies of the Sassendalen Group led Mork et aL to apply different names to the three units west of a projected lineament as compared with the central and eastern barriers east of it. If we combine the three formation thicknesses so as to consider points for an isopach map of the Sassendalen Group they are too scattered to give confidence as to any particular construction of isopach lines between them. If the projected lineament was an active Triassic fault as depicted in Mork et al. (1982, fig. 3a) it assumes that the fault runs sub-parallel to the line between two points with notable thickness contrast and the isopachs would run sub-parrallel to the fault. This is one extreme interpretation. The other extreme is to consider the surface between the two points as a regular gradient as follows. In rounded figures we may estimate a thickening of 100% westwards, say 350-700m or 400-800m, of the Sassendalen Group. The distance between the two adjacent points in the Mork et al.'s fig. 13a is c. 100 km which gives a slope for the bottom of the Group when the top is horizontal of 0~ ' or 0.41%. Taking the closest points from the steepest gradient gives about 0~ t or 1.22%. Now, allowing for errors in these data, we may exaggerate the distance to half and the thickness differential to 800 m which then would give a minimum gradient of 1 in 15 (say 3045' or c. 6.5%). Now this extreme slope would represent the cumulative differential subsidence over a period of between 5 and 10 million years and was never a sediment surface. So we are left with the problem of the line of the postulated fault. Mork et aL projected the Pretender Fault from the north. If needed an alternative postulated lineament might be considered: the Kongsfjorden-Hansbreen Fault Zone (KHFZ) which, unlike the other, has been argued independently to have an ancient history. In either case the trace of the fault zone (deflected and obscured by Paleogene tectonics) cannot be constrained where constraint is necessary. In favour of a distributed rather than a faulted subsidence is the intermediate thickness in an intermediate position in Oscar II Land recorded by Buchan et al. (1965) but not noticed in the fence diagrams of Mork et al. (1982). It was argued that the KHFZ bounded two distinct terranes which might be a reason for differential subsidence to be located along a hinge across an ancient fault zone. That possibility has to be weighed against the

effect of loading a developing delta system so that the sediment source to the west in part controlled the site of maximum subsidence. The simplest explanation might be that the extra loading of the delta front in the west compared with the deeper water to the east caused a ?maximum subsidence rate of 0.1-0.05 mm a -1 compared with 0.05 mm a -1 .

Late Ladinian time appears not to be represented by strata in Spitsbergen where a distinctive hiatus results in a clean break between the Sassendalen and Kapp Toscana Groups. A distinctive hard silicified bed often seems to cap the Botneheia-Bravaisberget formations and could have been indurated during this interval.

18.6.4

Late Triassic (latest Ladinian, Carnian, Norian and Rhaetian)

After the break a quite new situation emerged with the Kapp Toscana Group. The environment was one of marine regression (Fig. 18.1 lc). A sediment source with a prograding delta developed from the east and increased in effect while the western deltaic influence diminished. Even the marine sediments have a different aspect. Whereas before the shales were often calcareous, dolomitic and with phosphatic concretions, the Late Triassic marine deposits and especially those of the Tschermakfjellet Formation are typically sideritic and weather to a distinctive red. The sandstones also contrast in lithology. From mature sands with little feldspar the Late Triassic feldspar content is greater.

Latest Ladinian ( s u t h e r l a n d i Zone) Early CarMan.

The Tschermakfjellet Formation marine facies extend through the Central Basin and through to the western part of the Eastern Platform as Falcon's (1928) 'Blue and Purple Shales' in Edgeoya, but not in northwest Spitsbergen. With encroaching deltas from the east and a persistent facies contrast to the west, the typical marine basin became a lagoon with marine connections to the south, but uncertain links to the north where hitherto the affinity with the Sverdrup Basin had required some connexion. Within this basin, the Billefjorden Fault Zone continued to exercise some control in that only thin strata accumulated over the old Nordfjorden High to the west, with a thicker development on the eastern side. The siderite concretions may indicate a proximal environment with some flesh-water diagenesis. In south Spitsbergen, the Austjokelen Formation in Sorkapp Land ' . . . is laterally equivalent to the Tschermakfjellet Formation. The formation replaces the member rank of Buchan et al. (1965) and of Worsley & Mork (1978) in the Hornsund and the Sorkapp Land area'. 'The decrease in thickness southwards onto the Sorkapp Hornsund High (from 31 to 12m) follows the same pattern as the underlying formation'. (Mork, Knarud & Worsley 1992, p. 396). The Skuld Formation of Bjornoya is a more distant equivalent.

Carnian and Norian. The main deposit formed in this longer span of Late Triassic time was the De Geerdalen Formation. It was a marginal marine deposit in a proximal delta-front environment with some topset episodes and coal formation, often rich in plant material, but at the same time worked over in a shallow-marine environment with coarsening-upward rhythms. The sandstones are less mature with some potash feldspar and more plagioclase. The same tendency as in the lateral and underlying formation for sideritic concretions persists. The sandstones are poor reservoir rocks because of their immature nature and high lithic content. They were compacted early on. Thus the most distinctive change is that the central and eastern basin marine shelf deposits succumbed to deltaic influence; but this is no longer dominant in the west. There is evidence of land to the northeast and east, and of rivers flowing from it in a southwest

TRIASSIC HISTORY direction as seen across in Edgeoya (e.g. Lock e t al. 1978, pp. 30-31) (Fig. 18.12). Thick sandstones in southwest Edgeoya show a series of syn-sedimentary rotational growth faults. (Edwards 1976; Lock e t al. 1978). Moreover, the formation thickens markedly towards the Eastern Platform and it is probable that the seaway to the north, if not closed, was of a similar marginal facies.

~)

O/t

fluvial O Thick sandstones Only thin 9 fluvial sandstones Slides at base of formation

COAL ~ = ' ~ , , ~ ~ f " 9

O~

9

"9

COAL RARF~ .t

COAL ~

~c1r

COAL ? CC

9

ABSENT

359

Chlebowski & Wierzbowski (1983) reported a rhyolitic pyroclastic component in some thin layers of the upper part of the De Geerdalen Formation (within 5 m of the base of the Wilhelmoya Fm) from north of Wimanfjellet in Sassendalen. This was said to be the first record of Norian (to Rhaetian) volcanic activity in Svalbard. The volcanic minerals, of which the quartz is best preserved, are small enough to have been transported long distances (e.g. by wind). Mork et al. (1982) considered that most of the sediments were deposited in marginal to shallow-marine environments, showing a complex mixture of delta-lobe, distributary mouth- and barrier-bar, lagoonal and open marine interdistributary facies9 The sedimentary structures of most areas show redistribution of deltaic material by marine process (tides and waves)9Sandy distributary mouth-bar sequences are recognisable in Edgeoya, central, southern and eastern Spitsbergen while delta-top facies are locally seen in lower parts around Hornsund and east-central Spitsbergen and at the top in Edgeoya and Barentsoya (Lock et al. 1978; Mork et al. 1982). Crossbedding in distributary channel sandstones in central Spitsbergen indicates currents flowing from the northeast and east. Growth faults have been observed in southwest Edgeoya (Edwards 1976) pin-pointing the delta front. More detail was given by D. J. W. Piper in Lock et al. (Fig. 18.12)9The typical upward-coarsening sequence represents the transition from interdistributary shales and siltstones to sandstones of the delta-front, representing either offshore-bars or distributary mouth bars and, even locally, distributary channels9 The fluvial influence is strong in some areas, especially in the east. Reworking by tides and waves occurred at the top on abandonment and subsidence of the delta lobe, followed by a return to inter-distributary mud deposition. Lagoonal facies may further complicate the picture9 The domination of shales in the upper part of the sequence in northwest Spitsbergen suggests a lower energy lagoonal or estuarine environment. It may indicate either decreasing deltaic influence in Late Triassic time of the western delta system or simply a distal facies with delta

A

Fig. 18.12. Triassic sedimentation sequence on Barentsoya and Edgeoya (redrawn from D. J. W. Piper in Lock et al. 1978).

Fig. 18.13. Regional Triassic tectonics (redrawn from Heafford & Kelly 1988, fig. 3).

360

C H A P T E R 18

Kapp Koberg Member in Kong Karls Land and Flatsalen Member in Hopen). They are probably the latest Triassic deposits in Svalbard except for the earlier part of the ensuing arenaceous members. This sandstone episode is quite distinctive, the sands are clean, apparently continental, with plant fragments and coal seams. They are generally unconsolidated and thicken significantly to the east across the platform, whereas to the west of the Billefjorden Fault Zone the old Nordfjorden High becomes a significant feature again, with thin and remani~ deposits of Jurassic age. The mainly Rhaetian Wilhelmoya Formation also marks the beginning of the Jurassic-Cretaceous story. It is the third and uppermost unit in the Kapp Toscana Group and is a first order coarsening-upward sequence. The sequence of facies from this combined work begins with the Kapp Koberg Member, a marine deposit notable for its saurian bones. The lower part consists of poorly consolidated mudstones and siltstones with thin siderite beds. The upper part contains increasing amounts of sandstone, with well developed lenticulation and wavy bedding. It is interpreted as a marginal marine and offshore mud deposit grading upwards into barrier sands. The

lobes prograding elsewhere, e.g. Hornsund. However, there seems to be a trend of decreasing deltaic activity upwards in the De Geerdalen Formation in the western area, while in eastern areas a deltaic system from the northeast had a progressively greater influence on sedimentation accompanied by an eastward shift in the zone of maximum basin subsidence from eastern Spitsbergen to Barentseya, Edgeoya and Hopen.

?Norian-Rhaetian. After the De Geerdalen Fm deposition there is a marked change in the whole environment which has been recognised by distinguishing the Wilhelmeya Formation for the ensuing episode. Its age is probably at least Rhaetian, though late Norian has been suggested, as discussed earlier (e.g. Smith 1975; Bjaerke & Manum 1977; Korchinskaya 1980; Pchelina 1980). The change begins with a widespread marine incursion after some well-sorted basal sands. Bivalves and saurians are conspicuous but ammonoids are exceedingly rare. Some concretions continue to be sideritic, but phosphatic concretions predominate higher up (Rhaetian?). These deposits are thin but widespread (Bjernbogen Member in northeast Spitsbergen and Wilhelmoya;

ARCTIC SVALBARD

Stage -

-

SHELF

SEQUENCE QUEEN ELIZABETH ISLANDS

Pleistocene Pliocene Miocene

Beaufort

Oligocene

Forlandsundet Graben

Eocene Paleocene

WEST SPITSBERGEN OROGENY sandstones, shales Van Mijenfjrorden Group coals somebasic igneou~

EUREKAN OROGENY

Eureka Sound Maastrichtian Campanian NE SW Santonian sandstone -Konguk andshale (uplift and warping) Coniacian Turonian Strand Fiord basalts Cenomanian Bastion Ridge shale and __ - - Albian U Hassel sandstone shale --i Christopher shale, sandstone, shale I Aptian Carolinefjellet sandstone shale Barremian Helvetiafjellet continental sandstone Isachsen sandstone, shale, shale - coals and basalts Houterivian conglomerate with basalts _ Valanginian basic Deer Bay Mould Bay i Rurikfjellet magmatization Berriassian s h a lsiltstone e a n sandstone d ~ i- - ! - - Volgian Kimmeridgian Agardhfjellet ~ marine shales Awingak Oxfordian ~" siltstones Callovian Bathonian Adventdalen Group Savik Wilkie Point Bajocian m - - Toarcian ~o==o OoOoOo o Pliensbachian Sinemurian ~ ? Borden Island Hettangian Rhaetian . De Geerdalen continental sandstone Heiberg Norian v sandstone, siltstone Karnian Tschermakfjellet sandstone marine shale -

-

L

--i e-

-

-

__ Ladinian Anisian Spathian Smithian Dienerian Griesbachian Dzhulfian Kazanian Artinskian Sakmarian Asselian Orenburgian Gzelian Moscovian Bashkirian Namurian Visean Tournaisian

-

Botneheia "~

Sticky Keep

marine siltstone and shales

Blaa Mountain shales, calcareous siltstone

Schei Point _ j ' - sandstonesj r -siltstones -~ _- ~ _

Blind Fiord Bjorne sandstones and shales sandstones and congl.

Vardebukta Tempelfjorden Group

Kapp Starostin Limestone and cherts Gipshuken evaporites ~

Trol~ Fiord De~erbols Sabina Bay Belcher Channel

Tanquary _ Hare limestone Nansen Fiord sandstone - limestone shale siltstone Antoinette - limestone anh.vd" _rite ~ ~anyon - r,_.., Fiord Borup Fiord rnl~vdrit^sandstone ca,,,, u, ,L~llmestone--

limestone

Ebbadalen Svenbreen

Can y on Fiord evaporites sandstone limestone ~ continental sandstones with coal Emma Fiord

H6rbyebreen

--

Van Haven

Nordenski61dbreen

-

--

-

-

Fig. 18.14. Comparison of Arctic shelf sequences in Svalbard and the Queen Elizabeth islands plotted for the Tournaisian to Maastrichtian interval, between Devonian assembly and Cenozoic break-up of Arctic Pangea (from Harland 1975, table 11).

TRIASSIC HISTORY Arnesodden (shale) Bed, near sea level in northeast Svenskoya, has not been described- it may be an extension of the Kapp Koberg Member. It has been suggested that the Wilhelmoya Formation makes a regional transgression to form a shallow-marine shelf into which a delta was prograding from the ENE, with muds being deposited in some areas and sand in others (Mork et al. 1982). The sedimentary structures are typical of tidal sediments. The maturity of the sandstones and the frequent lag conglomerates suggest slow sedimentation and some reworking with depositional breaks. This may have been the result of lower relief in the source areas. Clay-lined burrows indicate that fine material was present which winnowed away. In east central Spitsbergen the upper part shows broadly deltaic environments with a complex of pro-delta, westward-flowing distributory channel, delta-top and shore-face facies. Cross-bedding in the distributory river channel sandstones indicates south westward flowing currents (Birkenmajer 1984e). Further east (e.g. Kong Karls Land) marine shales pass up through barrier sands into brackish, freshwater lagoonal and marsh facies with marine incursions; cross-bedding there suggests flow to N, NW and W.

18.6.5

361

respectively. The Urd formation is dominantly marine and the Skuld non-marine with marine incursions and influences. Mineralogically the Skuld shales have a higher clay mineral content than in the Urd. Kaolinite exceeds chlorite in the Urd, and is reversed in the Skuld. Feldspars are more abundant in the Skuld. Dolomite is only recorded in the Urd. Phosphatic nodules are common in the Urd and make up much of its top Verdande Bed whereas siderite is typical of Skuld nodules. Pyrite is dispersed in the Urd but forms discrete nodules in the Skuld Formation. Sedimentologically the whole succession exhibits coarsening-up cycles: one major (about 50 m) and two minor (about 5 m each) in the Urd, and four cycles in the Skuld Formation approximating 50m, 30m, 20m and 40m respectively (Mork et al. 1990). The remani6 Verdande Bed represents a still-stand possibly of 1 million years. The somewhat distinct structural effects in Bjornoya would be consistent with Bjornoya at that time being part of eastern North Greenland rather than north of North Greenland. Nevertheless a far more marked environmental contrast is between the Svalbard sequences and the Triassic succession of Central East Greenland which shared the West European red sediment facies.

Bj~rnoya

Bjornoya appears to belong to a structural terrane distinct from that of the rest of Svalbard regarding the incidence of tectonic disturbances. Nevertheless the two formations Urd and S k u l d separated by a time interval of perhaps 4 million years, parallel the developments in the rest of Svalbard that conveniently divides Triassic time between the Sassendalen and Kapp Toscana Groups

18.7 18.7.1

Triassic regional palaeogeology Tectonic framework

The previous chapter showed how the greater Barents platform/ shelf was assembled (17.6.1). The Uralian Orogeny which cemented

Fig. 18.15. Triassic palaeogeography of the Barents Sea. (a) Early to Mid-Triassic, (b) Late Triassic, redrawn and updated by S. R. A. Kelly from A. P. Heafford (1988, figs 12 and 13). For Legend, see Fig. 17.15(a), p. 337.

362

CHAPTER 18

a complex and coalescing Asia to Laurussia & Gondwana to form Pangea was not quite completed by Early Triassic time. Nevertheless this new Arctic Platform which comprised the shelf areas between the ancient nuclei of Anabar, Baltica, and Laurentia was set to receive a new layer of Mesozoic sedimentation. The similarities between Svalbard, Wandel Sea, Sverdrup Basin and Northern Alaska are familiar. Perhaps the most striking for Triassic stratigraphy is the parallelism of Sverdrup and Svalbard basins (e.g. Harland 1975b) (see Fig. 18.14) to the extent that in the early Triassic investigation of Svalbard some Cambridge geologists initially used the Sverdrup nomenclature. For example, the Botneheia Formation parallels the Blaa Mountain and Schei Point formations and the Vardebukta parallels Blind Fiord and Bjorne formations. The Triassic Period was perhaps a time of exceptional stability when Pangea remained intact. To the south there were signs of break-up which gathered pace in Jurassic-Cretaceous time. The principal Arctic disintegrating event was perhaps the rifting and volcanism in the West Siberian Basin. A possible reconstruction for this interval is presented schematically in Fig. 18.13 which follows the Arctic interpretation of Smith (1987) and of Heafford & Kelly (1988).

18.7.2

Triassic palaeolatitudes and climates

Harland, Pickton & Wright (1976) drew a curve plotting the estimated palaeolatitude of Spitsbergen from Silurian through Holocene time, i.e about 450 million years based on points every 10 million years taken from A. G. Smith's best fit criteria and J. C. Briden's palaeomagnetic data. That was mainly to show the latitudes at which coal in Spitsbergen was formed from Late Devonian through Late Paleogene time. It shows a jump from 10~ to 25~ in late Silurian-Early Devonian, a gentle rise to end Permian from 25 ~ to 40 ~ and a dramatic Triassic northward movement from 40 ~ to about 60 ~ and then up to nearly 80 ~ Steel & Worsley (1984, p. 114) and Worsley (in Aga et al. 1986) drew essentially the same curve to identify changing environments

especially with evaporites. In this respect Svalbard moved from hot dry Carboniferous through to wet temperate Triassic weather.

18.7.3

Sedimentary connections

Similar marine Mesozoic sequences are found from Alaska, through the Queen Elizabeth Islands, the Wandel Sea Basin of North Greenland, Svalbard, the Barents shelf and the TimanPechora region of Russia west of the Urals (Fig. 18.14). It thus appears that, at least for Early and Mid-Triassic time, there was a connecting seaway. In particular, middle Triassic organic-rich muds indicate anoxic depocentres in North Alaska, the Sverdrup Basin and Svalbard. They show such similar sequences that marine connexions must have been continuous. Figure 23.2 taken from Leith et al. (1992) shows a Mesozoic correlation chart with such organic rich marine mud rocks (OMM). Rich phosphates relate to the abundance of vertebrate bones and coprolites, possibly also to upwelling currents from the south in a semi-enclosed shelf sea. Worsley (in Aga et al. 1966, p. 69) attributed this possibility to the initial opening of the Proto-Arctic Basin. This would generally be on the far side of the sedimentary belt from Laurentia. But in Later Triassic time, land seems to have shed sediments from the northeast. Land in that direction would be consistent with the relict Lomonosov Orogen presumably, eroded down to near sea level by then. Seismic surveys suggest appreciable thicknesses of Early and Middle Triassic strata in the Barents Shelf, but not in the positive area of Bjornoya, which may have been on the seaboard of eastern North Greenland. Not only do the Mesozoic sequences extend both northeast and southwest from Svalbard, but the configuration was related to the Carboniferous framework. Therefore the Triassic chapter epitomises the relatively stable Arctic Pangea. The sedimentary connexions within the Sverdrup Basin were noticed, not as a consequence, but as a reason for locating Spitsbergen north of Greenland and near to Ellesmere Island during that interval (Fig. 18.15a, b).

Chapter 19 Jurassic-Cretaceous history W. B R I A N 9.1

HARLAND

with contributions with SIMON

Early work, 363

19.1.1 Sedimentary rocks, 363 19.1.2 Igneous rocks, 363 19.2 19.3

Jurassic-Cretaceous structural frame, 365 Stratigraphic scheme, 366

19.3.1 Svalbard, 366 19.3.2 Hammerfest Basin, Barents Sea, 368 19.4

Jurassic-Cretaceous time scale and correlation (W.B.H. & S.R.A.K.), 368

19.4.1 19.4.2 19.4.3 19.4.4 19.4.5 19.4.6

The Jurassic-Cretaceous international time scale, 368 Ammonite zonation, 369 Belemnite ages, 371 Bivalves, 372 Microfossils, 372 Jurassic-Cretaceous correlation in Svalbard, 372

19.5

Jurassic-Cretaceous formations, 372

R. A. K E L L Y

19.5.3 19.5.4 19.5.5 19.6 19.6.1 19.6.2 19.6.3

Helvetiafjellet and Kong Karls Land formations, 375 Carolinefjellet Formation, 376 Jurassic-Cretaceous basic igneous rocks, 377

19.7

Jurassic-Cretaceous events in Svalbard (W.B.H. & S.R.A.K.), 381

19.7.1 19.7.2 19.7.3 19.7.4 19.7.5 19.7.6

Latest Triassic-Early Jurassic events (Rhaetian-Toarcian), 381 Mid-Late Jurassic events (Bathonian-Tithonian), 381 Neocomian events (Berriasian-Hauterivian), 382 Barremian events, 382 Aptian-Albian events, 382 Late Cretaceous (Gulf) events: (Cenomanian-Maastrichtian), 382

19.8

Svalbard in a Jurassic-Cretaceous regional context (W.B.H. & S.R.A.K.), 383

Jurassic-Cretaceous biotas, 378

Marine biotas, 378 Terrestrial biotas, 380 Jurassic and Cretaceous climates, 380

19.5.1 Wilhelmoya Formation, 373 19.5.2 Janusfjellet Subgroup, 373

19.8.1 The tectonic frame, 383 19.8.2 The sedimentary sequence, 386

Jurassic-Cretaceous follows Triassic history with minor change. It was an interval dominated by deposition of marine muds, silts and sands, with occasional non-marine environments on advancing deltas (Parker 1967; Harland 1973a; Kelly 1988). Subdued topography contrasted with Triassic and Paleogene terrains. But there was also Late Jurassic and Early Cretaceous intrusion of basic sills and volcanism in eastern Svalbard. Figure 19.1 shows the distribution of Jurassic and Cretaceous deposits in Svalbard. The two periods (208-65Ma) span 143 million years but the stratal record for this interval totals only 1700m of which more than half was deposited in Albian time. The Jurassic-Cretaceous rocks of the eastern platform, presently cropping out on some islands, represent a relict of a once continuous sheet of strata, which is still preserved extensively across much of the Barents Shelf. The Triassic-Jurassic boundary is marked by seemingly continuous facies from Rhaetian to Toarcian; but then follows a contrast between the main Spitsbergen Basin (which hardly subsided) and the Eastern Platform. The contrasting areas of east and west Svalbard were divided by the continuing activity along the Billefjorden lineament. To the east, subsidence permitted a complex and variable sequence resulting from deltas from the east (marine and non-marine) through Liassic to mid-Bathonian time. To the west there was little evident subsidence and only condensed deposits of the uppermost Wilhelmoya Formation were washed by shallow seas. This part of the story concluded the history of the Kapp Toscana Group. A Late Bathonian marine transgression transformed east and west Svalbard, with the formation of dominant marine shales of the Adventdalen Group that continued through to Albian time. Subsidence was more evident in the west with the beginnings of the Central Basin and even marked by mid-Jurassic anoxic environments. There was Late Jurassic-Early Cretaceous instability with stratigraphic breaks and some disturbances in the east before Barremian time. Moreover, the Late Jurassic-Early Cretaceous igneous activity was greatest in the east. Following the relatively rapid Aptian-Albian subsidence in the west, to form the Central Basin with its depocentre to the south, was the final Mesozoic episode. This corresponded to the absence of Late Cretaceous outcrops in Svalbard. It was an interval of tilting or warping with uplift to the north. As a result, Mesozoic strata were successively removed northwards and peneplaned by Early Paleocene time. These events presage mantle heating prior to the opening of the Eurasia Basin along the Gakkel Ridge. Recent economic interest has centred on the western shales with some Mid-Jurassic anoxic facies as source rock and on the nearly unconsolidated sands of the Early Jurassic eastern development

as potential reservoirs (Fig. 19.2). The shales with TOC of usually 1-4% reach 12% in Callovian time. The sandstones may have porosity up to 25% and 150 mD permeability. Historically coal seams were significant. They are abundant in non-marine Cretaceous rocks, but generally too thin to exploit in competition with the Early Carboniferous or Paleogene coals. They were worked exploratively in 1920-21 (Smith & Pickton 1976). The Early-Mid-Jurassic phosphatic concretions of the Brentskardhaugen Bed have P205 compositions between 9 and 17% and contain a striking uncrushed marine fauna (Bfickstr6m & Nagy 1985). _

19.1 19.1.1

Early work Sedimentary rocks

Initially, Jurassic-Cretaceous research lagged behind pre-Jurassic and post-Cretaceous studies because of the relatively poor preservation of macrofauna in the predominantly mudstone facies. Contemporary knowledge was reviewed at intervals (Nathorst 1910; Frebold 1935; Orvin 1940; Major, Harland & Strand 1956; Parker 1967; Harland 1973a). This knowledge had to a large extent been limited to macro-fossiliferous beds, horizons or niveaux until Parker (1967), from the systematic measurement and description of sections and collections related to them, applied a lithic scheme. The earliest systematic scheme was probably by Pompeckj (1899) and used by Nathorst (1910) with 13 numbered and named beds, grouped according to estimated age (Fig. 19.3). Frebold (e.g. 1951) was the first to attempt a palaeogeographic synthesis of Svalbard in relation to the Barents Shelf, but not entertaining any palinspastic mobilism. Similarly in a global context Arkell (1956) compiled Svalbard Jurassic data.

19.1.2

Igneous rocks

Keilhau in 1829 (1831) had noted a dark syenite at Kvalpynten in Edgeoya and Robert (1842) described a 's61agite' (Sy6nite hypersth6nique) of blackish green colour, the only igneous rocks noted in Bellsund. Nordenski61d referred to the rock as the Hyperite and noted its vast extent through Svalbard and its uniformity in appearance and composition. Its fullest development was seen in Hinlopenstretet. He interpreted the rocks as indurated volcanic

364

CHAPTER 19 /9 ~

/12 ~

---81 ~

/15 ~

/18 ~

121 ~

/24 ~

\27 ~

SVALBARD JURASSIC AND CRETACEOUS OUTCROPS

Q 80

80 ~

5

0

+

~ , ,z,',

" "" ~

i" = . =.

.,, ~,

80:

' i 9 ,

I I i, 9u

.i

9

I r'~l

.'.1 / 9 t= 9

t, I

.j "

9 " '

/.,~ . ~ , 9

~1"

%"-

~

9 9 - '~,

i

79~ 9;

9 |.i .i

I:"

I

79 ~

'

Z " i

27 ~ 9 .o ,I

%%'1#

Cretaceous l a v a s in s e d i m e n t s above Jurassic and Triassic strata

~-,-... ,~" 78 ~ .r

.; . ..

:i

0"

9 .'..: 9

i ~

,

78~

.;

's

"~/'

.

.'."?

.,. ;'

7 7~

+

I Post-Cretaceous

Early Cretaceous dolerite sills

~

/

Early Cretaceous sediments

/12 ~ I ~ i J

~

Jurassic strata

9 -~..

9

Pre-Jurassic

74~ '

0

76~ .~S & L M . ~

115 ~

1

19~

21 o

~ 124 ~

100 76 __~

Fig. 19.1. Map of Svalbard showing the distribution of Jurassic and Cretaceous outcrops. Relevant place names are detailed on maps in Sections 4.3 and 5.6.

JURASSIC AND CRETACEOUS HISTORY

365

z

O n" ..j << m

+

m

_+,+<me++,+..

m

8

LU

oo

<

+

~0 0 ~

.e

wz

2 0 0 0 .=- . , , . .

,e, ._1 ._1

03

._, -,-o

Z UJ

~0 ~

7-a.

0 o

,., 9

19oo 9"" "'" "'" "

'LI. "

215

~o

o n-

shallow

1800-

":'"'"'-:

1700

0

marine

I

with

3

IV

NONE

shoals 1600-.....,, I,,-

111

8Z

:I: >

u"

50 100

i 1500

. . . . . . '. . . . . "" ~arginal marine (coals) " " 9 * ' , ". ". : ' to fluvial . .

1400-.

.---..-'~ 9 .'= dietal m a r i n e

to deep shelf

--

I-300

_J .J ul :~

.

.

III / IV

1

1300 Or)

.

2

II I

(II)

1200-

4

1

1 1 0 0 -r r IJ,.l

to deep shelf

1000

4

resNwvolr

potentials

FAIR to

GOOD for

GAS

GOOD for

distal

z ~d

NONE

III / II

OIL

and GAS

10

m

< z

0

deltaic to shallow marine l....... . . . . coals deltaic in w e s t

9 0 0 -- 3 ~ , , - - e r ~ ' ~ v " 9"

N

800 - " " " - - . "

,

uJ ~ '"N

75

700 -

"

" ' " "" . . . . - - " "--

9- . . . . . 600 . . . . . . .

to

shallow marine

,,,

3 prodelta to shallow madne 0 + I - a

<

o

~_~ 75

_J

,,z,

l l e e O I l l

__

m

a.

I'-" Fig. 19.2. Hydrocarbon potential and depositional environment of Triassic to Cretaceous rocks of Svalbard (with permission from Mork & Bjoroy 1984).

<1: ~RA!

~

~

eZ

50

100 -

aa

ashes or gravel from destroyed plutonic rocks. Even after von Drasche (1874) had demonstrated their igneous emplacement Nordenski61d maintained his view of contemporaneous formation. This may be a relic of the Werner-Hutton (Neptunist-Plutonist) debates from the previous century. In the meantime, contemporaneous Mesozoic basaltic lavas were described from Franz Josef Land and by Hamberg (1899) from Kong Karls Land. Perhaps the first systematic a c c o u n t resulted from the Russo-Swedish Arc of Meridian Survey, by Backlund (1907). At that time, especially under De Geer's (1909) influence, there was much speculation on the configuration of fjords in relation to faulting, and the 'diabases' were interpreted in that context. Holmes (1918) included Svalbard occurrences in his survey of Arctic basaltic rocks. There was subsequently some confusion with the basaltic rocks of north Spitsbergen now known to be Tertiary or even Quaternary in age, though of course the connection may well be genetic. The above account is summarized from the second systematic paper on the subject (after Backlund's) namely that by Tyrrell & Sandford (1933). Thereafter there have been supplementary investigations but no further major review.

2

__ to d e e p m a r i n e

i

2_', ~

75

--

FAiR

some reservoir potlntmis

for

GAS

III

FAIR G A ~

II (111, I)

RICH for OIL

III

GOOD

e

distal shallow

+oo-

III

pobmfials

1

-

500 -

03

0

reservoir

NONE

5

lowO2

12

s h a l l o w to distal

shallow marine

3 7

shallow marine

1

III

POORfor

3

(IV)

OIL,forGAsFAIR

9 2_."

--

1

0

(11)

main source rock

for

OIL

o_

19.2

Jurassic-Cretaceous

structural

frame

The features are shown on the map (Fig. 19.4). The N-S Billefjorden and Lomfjorden fault zones activity is evident in Jurassic-Cretaceous strata. The former between Sassenfjorden and east of Van Keulenfjorden and the latter in the Agardhbukta hinterland. In addition to movement on the faults, especially in Janusfjellet Subgroup time, the terrane between them generally acted as a positive axis separating Early Jurassic differential subsidence to the east and Later Jurassic-Early Cretaceous subsidence to the west. The Hornsund High, trending along the locus of the later West Spitsbergen Orogen, bounded the Central Basin. To the west the western record was removed by that uplift. That no Jurassic-Cretaceous rocks crop out north of the latitude of Wilhelmoya resulted from Late Cretaceous uplift and erosion. The Central Basin is thus defined as east of the (later) West Spitsbergen Orogen and the Hornsund High, and west of the Billefjorden-Lomfjorden axis and south of the Wilhelmoya latitude9

366

19

CHAPTER I

I Stolley 1911, 19121Hagerman 1925 Gregory 1921

Nathorst 1910, 1913

I Heel & Orvin 1937

I

Rozycki 1959

Buchan et a11965

I Nagy 1970 [ Merk et al. 1982

Parker, 1966, 1967

Pchelina 1980,1983, Gramberg 1990

Dypvik et at. 1991 SchSnrockt]ellet Mbr

Unterste halle Sandsteinreihe

Kvalv&gen Fm

ZUlerberget Mbr m

Dentalienschichten

Ditrupa shale series

Ditrupaschichten

Camline~ellet Fm Langstakken Mbr

Upper Lamina sandstone

Festningen sandstone

Ginkgoniveau Pityophyllumniveau Elatidesniveau Festungssandstein

Glitret]ellet Mbr continental series

Helvetiafjellet Fm

Helvetiafjellet

Fm

Festningen Mbr Ullaberget series

Ullaberget Mbr Rurikfjellet Fm

Rudkrlellet Hzn & Srs

Wimant]ellet Mbr Mycklegardt]ellet Bed

Aucellenschichten

Opdalen Mbr Dr~nbreen Bed

Ingebrigtsenbukta series

a, Schwarze Schiefer

Plateau Flags

Marhegda Bed Brentskardhaugen Bed*

Lias conglomerate Fossesandstein

Konusen Fm

AgardhfJellet Fm

Lardyt]ellet Mbr

~ AgardhIiellet Fm

conglomerate

Silodden Fm

Oppdals~lta Mbr

c. Schwarze Schiefer b, Dunkgraues Schiefer

Kikutodden Mbr

Slottsmeya Mbr

rirolarpasset series

Aucella shale

Ymerbukta Fm

Dalkjegla Fm

Dalkjegla Mbr

Lower Lamina sandstone Shore sandstone

Hzn & Fm J

Innkjegla Mbr

Cretaceous shales Sandsteinreihe c. Lioplax-Schichten b. Elatides-Schichten a. Ginkgo-Schichten Festungssandstein

Zingerfjelletl

o. ~ J (Wilhelm~ya Fro)

Smallega Mbr (S)

.• .-- "r

KnorringfJellet Mbr (N] ~

3

I..-

c~

Brentskardhaugen Mbr Teistberget

Fm

Fig. 19.3. Historical review of the principal stratigraphic schemes for the Jurassic and Cretaceous rocks of Spitsbergen.

new nomenclature based on described sections took place. Unfortunately, the new scheme did not emerge unchallenged and various revisions were later attempted, not only because o f more data, but to suit particular interpretations. In this work, the object is to settle on a single classification and nomenclature based on a compromise between priority and practicality; this is set out in Fig. 19.5. In this work that scheme is applied without further discussion. Carolinefjellet Formation (Parker 1967). Three units set out by Hagerman (1925) were the basis for this formation. Hagerman 1925 Parker 1966

Parker 1967

Shale Upper Lamina sandstone Cretaceous shales Lower Lamina Sandstone

Fig. 19.4. Jurassic and Cretaceous structural framework.

19.3 19.3.1

Stratigraphic scheme Svalbard

F r o m early this century, the main outlines o f Jurassic-Cretaceous stratigraphy were well known, especially the ages o f most fossiliferous horizons. However, from 1960 onwards the conversion to a

Nagy 1970 Sch6nrockfjellet Mbr Zillerberget Mbr

Langstakken Mbr Carolinet]ellet Formation

Innkjegla Mbr

Dalkjegla Mbr

The Carolinefjellet Formation also corresponds to the Dentalium Schichten of Nathorst (1897a, b, 1910, 1913) and of Hoel & Orvin (1937) and to the Ditrupa Shale Series of Stolley (1912), and Rozyicki (1959). The Carolinefjellet Formation was defined by Parker (1967) to include four members, then a higher fifth member was introduced by Nagy (1970) who also named the fourth. It is a dominantly marine formation of sandstones and shales, limited to Spitsbergen and there is no difference of opinion as to its status. The members are: Sch6nrockfjellet Member, Albian Zillerberget Member Langstakken Member Innkjegla Member Dalkjegla Member, Aptian. Pchelina (1980, 1983) with Gramberg, Krasil'shchikov & Semevskiy (1990) introduced alternative schemes of units shown in the right-hand column of Fig. 19.3. They have no priority and would confuse if applied. Some of the suggestions are based on age opinions rather than mappable rock units.

JURASSIC AND CRETACEOUS HISTORY

[W I L H ~ A

SPITSBERGEN

367

KONG KARLSLAND

Flrkanten Formation

Van Mijenfjorden Group

Sch6nrockfjellet Mbr Zlllerberget Mbr s

Carolinefie,at Formation

Lsngstakken Mbr 4 InnkJegla Mbr 4 Oslkjegla Mbr 4 K0kenthalfJell~ Member

FeMnlngen Mbr

....... 4 HUfllGJOIIOl

Formation

Fig. 19.5. Summary of the principal lithostratigraphic units of the Adventdalen and Kapp Toscana groups in Svalbard. Sources: (1) Rozycki (1959); (2) Buchan et al. (1965); (3) Parker (1967); (4) Nagy (1970); (6) Flood e t a l . (1971); (7) Smith (1975); (8) Worsley (1973); (9) Bjaerke & Manure (1977); (10) Smith e t a l . (1976); (11) Birkenmajer (1975); (12) Worsley & Heinz (1977), (13) Birkenmajer (1980a); (14) Dypvik e t a l . (1991a); (15) Bfickstrom & Nagy (1985).

Uilaberget Mbr 1

~

-

Slottsmeya Mbr

O~

Oppdslstita Mbr

I I

.

..

4

I AgaranI fjellet ~= I Formation

='~

I

"3

[ 4 '1

]~7=~; ~

~3~Smallegga

]

10 HArfagrehauger Member

lO Tordensk-

~4

loume.mM

Wlman~ellet Mbr

5 [I" s o ~

1r

Kong Karls Land Fm

4

Helvetiaf]ellet a e Gl~re~elletMbr 4 Formatzon

eml~lr

o1,; t

Dun6rfJellet

Member

Retziue'l~

fJellet Member

LardyfJellet Mbr

OppdalanMbr 14

lO Pssset Member

(Dmnbreen Bed) 'M 15 (Ma,l~e~:~Bed)

,~

(Brentaksrdhsugm Bed) unnamed a h a l u

14

I~1~,

.c~...~....----~Fs 14

KnordngfJellet Mbr 2e

[

Mohnbegda ~l~r2 SJegrenfJt ~

_---; BJ.rnbogen Mb#

De Geerdalen Formation

1

(AmeJmddenBed)

0

~

l~grTM

LyngefJellet Mbr0 ,7-

Flatulen Mbr o 7-

IversenfJellet

Mbr

0

,~E~ frschermakfielletF o r m m l o n ~

Helvetiafjellet Formation (Parker 1966, 1967) was defined in Spitsbergen as comprising the Continental Series of Rozycki (1959) including the units of Hagermann (1925) thus: Hagermann (1925) Parker (1967) Shore Sandstone Glitrefjellet Member Festningen Sandstone Festningen Member The age is probably Barremian, and the base is Barremian. In Kong Karls Land, Smith et al. (1976) defined the Kong Karls Land Formation, the uppermost of three formations in those islands. It is distinguished by conspicuous lava flows. It has been correlated approximately with the Helvetiafjellet Formation and is equivalent to units 10, 11, 12 & 13 of Pompeckj (1899)and Nathorst (1901), 11 and 13 being basalt lavas. Smith et al. distinguished three members for the three areas in two of the islands in which the Formation was described: in Svenskoya Kfikenthal Member in western Kongsoya H~trfagrehaugen Member in eastern Kongsoya Johnsenberget Member. Edwards e t a l . (1979) protested at the multiplication of names and, proposed that the name Kong Karls Land Formation be subsumed in the Helvetiafjellet Formation and its members be members of the Helvetiafjellet Formation. They may be of the same age, but their overall lithology differs, not least by the interbedded lavas (Pickton et al. 1979). In this work, the Kong Karls Land and the Helvetiafjellet formations will be distinguished as being more useful for discussion. The three members of the former are also retained. Certainly the equivalent of the Tordenskjoldberget Member is already recognised offshore (Arhus e t a l . 1990). Janusfjellet Formation (Parker 1966, 1967). The Aucellaschichten of Nathorst (1897a, b, 1910, 1913) and of Hoel & Orvin (1937), or the Aucella (=Buchia, a bivalve) shale of Hagermann (1925) was named by Parker (1966) the Janusfjellet formation on the suggestion of Harald Major. It comprised the: Upper Janusfjellet formation Lower Janusfjellet formation 'Lias' conglomerate at base B u c h a n et al. (1965), in their review of the Triassic rocks of Svalbard, also excluded the 'Lias' c o n g l o m e r a t e f r o m the top of their D e G e e r d a l e n M e m b e r (at the top of their K a p p T o s c a n a

F o r m a t i o n ) so including it in the Janusfjellet F o r m a t i o n as did P a r k e r (1966). T h e n P a r k e r (1967), on the basis o f m e a s u r e d sections, defined his units m o r e fully c o m b i n i n g his Janusfjellet, Helvetiafjellet a n d Carolinefjellet units in the A d v e n t d a l e n G r o u p . The r a n k of the Janusfjellet unit was raised thus: JanusfjeUet Subgroupcomprising Rurikfjellet Formation Agardhfjellet Formation and, with what may have been faulty reasoning, he relegated the Brentskardhaugen Bed to the top of the underlying Kapp Toscana 'Formation' instead of making it a basal conglomerate (Section 18.3.1). Subsequently the Janusfjellet unit appeared as a formation in a number of publications following (e.g. Major & Nagy 1972; Harland et al. 1974; Edwards et al. 1979). Rozycki (1959) had already recognized three divisions between the 'Lias conglomerates' and the Continental Series (Helvetiafjellet Formation) including the Ingebrigtsenbukta, Tirolarspasset and Ullaberget Series in the southwest of Spitsbergen. There is a marked erosion surface at the base of the Tirolarpasset Series and this is taken to be equivalent to erosion at the base of the Rurikfjellet Formation. Thus the Tirolarpasset Formation can be absorbed into the junior, but better known and understood unit, the Rurikfjellet Formation. Likewise, the Ingebrigtsenbukta Series can be absorbed into the Agardhfjellet Formation. The sedimentologically distinct Ullaberget Series is here reduced to member status of the Agardhfjellet Formation. However, a renewed study of the Janusfjellet sequence by Dypvik et al. (1991a, b) showed that so much detail was forthcoming that it was best included in 10 named units (members & beds), in two formations in a subgroup. Moreover, Dypvik et al. argued for the reinstatement of the Brentskardhaugen Bed as the lowest unit as in the following scheme (Fig. 19.5) as had already been suggested by B~ckstr6m & Nagy (1985). Dypvik et al.'s scheme is followed below. Only one argument is questioned, namely that the subgroup should represent the Bathonian to Hauterivian time span. That may well be but the lithic scheme should now stand regardless of opinions as to estimated ages. RnrikfjeHet Formation (Parker 1967). The base of the Rurikfjellet Formation is marked in the western Central Basin by a non-sequence and

368

CHAPTER 19

local unconformity. The basal unit, the Myklegardfjellet Bed, was originally defined by Birkenmajer (1980) and placed between the Rurikfjellet and Agardhfjellet formations, and not included in either. Dypvik et al. (1991) placed the bed at the base of the Rurikfjellet Formation, but made it ambiguous as to whether it lay within or below their new Wimanfjellet Member. To clarify the situation, the Myklegardfjellet Bed is placed here at the base and within the Wimanfjellet Member, which in turn is placed within and at the base of the Rurikfjellet Formation. In western Torell Land, the Polakkfjellet Bed (Birkenmajer 1975) is placed at the base of the Formation. It has been suggested that it was coeval with the Mjolnir impact (Dypvik, Nagy & Krinsley 1992; Dypvik et al. 1996) The shales of the Wimanfjellet Member locally, in the Torell Land area, give way to sands originally defined as the Ullaberget Series (Rocyzcki 1959). The sands were recognized, but only informally, by Parker (1967) and were reduced to member status by Birkenmajer (1975). Dypvik et al. (1991a) usefully retain them thus. Agardhfjellet Formation (Parker 1967). Dypvik et al. included the Brentskardhaugen Bed, together with the overlying Marhogda Bed and Dronbreen Bed, all within the lower coarse Oppdalen Member of the Agardhfjellet Formation. The bulk of the overlying shales were placed by Dypvik et al. in the Lardyfjellet and Slottsmoya members which are separated by the markedly silty and sandy OppdalsSta Member. Kongsoya Formation (Smith et al. 1976). The Kongsoya Formation was named and subdivided by Smith et al. (1976), and is restricted to Kong Karls Land. On Svenskoya it is entirely represented by shales of the Dun6rfjellet Member, while, on adjacent Kongsoya, three members are recognized: a lower clay, the Passet Member; a shale, the Retziusfjellet Member; and a distinctive limestone, the Tordenskjoldberget Member. The relationship between the lithologically similar Dun6rfjellet and Retziusfjellet members cannot be estimated from onshore outcrops. However, the Nordaustpynten Shale can probably be placed safely within the Retziusfjellet Member. Edwards et al. (1979) argued that the members of the Kongsoya Formation should be members of the Janusfjellet Formation and that the Kongsoya Formation be eliminated. It is now convenient, with a Janusfjellet Subgroup, to retain the identity of the Kongsoya Formation and to include it in the Subgroup. Wilhelmoya Formation (Worsley 1973). The formation was proposed by Worsley (1973). However, Smith (1975) who had also worked on the rocks in 1969, referred to it as the Wilhelmoya Member, including it in the De Geerdalen Formation at the top of the Kapp Toscana Group because the Brentskardhaugen Bed (Lias conglomerate), claimed by Worsley as part of his Wilhelmoya Formation, had been included by Parker (1967) at the top of the De Geerdalen Formation. Thus, until Worsley & Heintz (1977) proposed to reduce the scope of the De Geerdalen Formation, Smith had been correct. As already noted the matter was further complicated because Parker had originally included the Brentskardhaugen Bed at the base of his Agardhfjellet Formation in his Janusfjellet subgroup. Accepting here that the Brentskardhaugen Bed again belongs to the succeeding Formation (and is of Bathonian age, though containing derived fossil Toarcian material) the definition of the Wilhelmoya Formation is somewhat simplified. The type section in Wilhelmoya, supplemented by a section in neighbouring Hellwaldfjellet on the mainland is not affected by the above considerations. The succession given by Worsley (1973) supplemented by Smith (1975) is: Tumlingodden Member, 28 m Transitional Member, 33 m (but included in the Bjornbogen Member, 19m Basal Member 7 m (but included in the Bjornbogen Member by Worsley & Heintz 1977). Worsley made lithological correlations with the highest units in Hopen, later named Lyngefjellet & Flatsalen formations by Smith et al. (1975). Worsley's case is accepted here for those units to belong to his formation and so become members of it. By extension, the members of the Svenskoya Formation of Smith et al. (1976) would also become members of the Wilhelmoya Formation and include the Kapp Koberg member of Worsley & Heintz (1977). There is thus a clear definition of the Wilhelmoya Formation in eastern Svalbard (probably Rhaetian to (relict) Toarcian). The variety of sediments within the Wilhelmoya Formation led Pchelina (1980) to recognize the Sorkapp Fm (inadmissible because preoccupied) in the south of Spitsbergen, the Teistberget Fm in the east and the Tumlingodden Fm in the northeast; and Mork, Knarud & Worsley (1982) to separate the Knorringfjellet and Smalegga members which represent the

whole of the Wilhelmoya Formation in the northwest Central Basin and southern Central Basin respectively. There was a move (e.g. Edwards et al. 1979) for the Wilhelmoya Formation to include any rocks thought to have been formed in the time interval between the De Geerdalen Formation and the Janusfjellet unit, such as the Passet Member of the Kongsoya Formation (of Smith et al. 1976), and this was followed by a number of authors who did not heed the critique by Pickton et al. (1979) immediately following Edwards et al. (1979). If age correlation becomes a major criterion for the definition of lithic units, the units may not have a clear mappable lithological unity in the field, and then stability of nomenclature is threatened by changes of opinion as to age or sedimentary cycles. Thus, some authors have shown Passet Member rocks as Agardhfjellet Formation (e.g. Bjaerke 1977) others as Wilhelmoya Formation (Lofaldi & Nagy 1980; Smelror 1988) after they were first defined as Kongsoya Formation. It seems that a desire to simplify and then compound units according to interpreted environment sequences is partly at the root of some changes. Alternatively, the desire to make lithic units into time intervals is also at work. If an approximately Hettangian to Toarcian interval needs a name, Liassic is correct.

19.3.2

Hammerfest Basin, Barents Sea

At the conclusion o f Section 18.3.3 the possibility of integrating Svalbard and Barents Sea stratigraphy was mentioned. This is obviously of interest to petroleum geologists. As with the Triassic units the n o m e n c l a t u r e of Jurassic-Cretaceous units for the H a m m e r f e s t Basin (Worsley e t al. 1988) has been included in the stratigraphic lexicon and index in Part 4. In this case the Svalbard nomenclature could with little difficulty be applied to the Barents Sea. Late Cretaceous strata are evident there (Nygrunnen Group) while absent t h r o u g h o u t Svalbard.

19.4 19.4.1

Jurassic-Cretaceous time scale and correlation The Jurassic-Cretaceous international time scale

The remarkable sequence o f a m m o n i t e species, especially Jurassic, permits a degree of stratigraphic discrimination not available for earlier history and only again in the Quaternary record. However, there are only a few horizons in Svalbard amenable to such refinement and generally correlation is possible only to stages or substages rather than to the 74 or m o r e constituent chrons of the Jurassic Period. The conventions as to the eleven Jurassic and twelve Cretaceous stages are almost agreed in terms of their constituent chrons as well as their classification as shown in Fig. 19.6. The Triassic-Jurassic b o u n d a r y is not m a r k e d by a distinct lithological boundary, but lies within the upper units o f the Kapp Toscana Group. The earliest recognized Jurassic assemblages o f Svalbard are palynological and occur within the Wilhelmoya F o r m a t i o n on K o n g Karls Land, where Hettangian/Sinemurian p a l y n o m o r p h s occur in the M o h n h o g d a and Sjogrenfjellet m e m b e r s of Svenskoya and K o n g s o y a respectively (Smith e t al. 1976; Bjaerke 1977). On Wilhelm o y a and the closely related outcrop on adjacent Spitsbergen at Hellwaldfjelllet, palynological assemblages in the T u m l i n g o d d e n M e m b e r below the Brentskardhaugen Bed are of unspecified Early Jurassic age (Bjaerk & Dypvik 1977) and f r o m a poorly defined horizon, K l u b o v (1965a) recognized Pliensbachian foraminifera. In the Central Basin of Spitsbergen p o o r 'PliensbachianToarcian' p a l y n o m o r p h assemblages were recognized in the Wilhelm o y a F o r m a t i o n (unit E) Sassenfjorden (Bjaerke & Dypvik) and the Toarcian a m m o n i t e P o r p o c e r a s is reported from Rurikfjellet (B~ickstr6m & Nagy 1985).

The Jurassic-Cretaceous boundary. There is still some d o u b t over the precise use of the standard (Tethyan) stage names 'Tithonian'

JURASSIC AND CRETACEOUS HISTORY

Higher time divisions

International stages (Boreal usage)

Chronozones Terminal

My

Ma

Initial

65

g

-~

Pachydiscus neubergicus

Acanthoscaphites tridems

Bostrychoceras polyplocum

Placenticeras bidorsatum

9.0

~ ~

~anto~

Placenticeras syrtale

Texanites texanus

3.5

Coniacian

Parabevalites emschari

Forresteria petrocoriensis

Turonian

Romaniceras devedai

Campanian

ID

O LU (~ W

-~9 v

86.5 2.0 2.0

Mante#iceras mantel#

6.5

Albian

Stolickzkaia dispar

Leymedella tardefurcata

15

Aptian

Diodocheras nodosocostatum

90.5 -

112-

Silesites seranonis

.~

Hauterivian

Pseudothurmannia angulicostata

~

g

Valanginian

Neocomites callidiscus

Z

Berriasian (Ryazanian)

FaurieOa boissieri

"lqthonian Volgian

_~ |

(.3

_E ~ Kim~e.dgian

Fm 124.5-

Nicklesia pulchella

7.5

Acanthodiscus radiatus

BerriaseOa jacobi

Helvetiafjellet& KongKarlsLandfins

135.0-

,E

g 140.6-

Hybonoticeras hybonotum

~ E 0

5.1 145.8

Durangites

, m

6.5

152.1- ~

Aulacostephanus autissiodorensis

Pictonia baylei

2.6

Oxfordian

Amoeboceras rosenkrantzi

Quenstedtoceras mariae

2.4

Callovian

Ouenstedtoceras lamberti

Macrocephalites macrocephalus

4.2

~g ~ uJ

154.7-

~

Bajoeian. N o ammonites are recorded from Svalbard. Elsewhere in the Arctic (e.g. East Greenland) Cranocephalites is characteristic.

161.3-

Bathonian

Clydoniceras discus

Zigzagiceras zigzag

4.8

~

C3

gajocian

Parkinsonia parkinsoni

Hyperlioceras discites

7.4

Aalenian

Graphoceras concavum

Leioceras opa#num

4.5

Toarcian

Dumortieria levesquei

Dacty/ioceras tenuicostatum

9.0

Pliensbachian

Pleuroceras spinatum

Uptonia jamesoni

7.5

Sinemurian

Echioceras raricostatum

Arietes bucklandi

9.0

Hettangian

Schlotheimea angulata

Psiloceras planorbis

4.5

Rhaetian

Choristoceras marsh/

166.1 173.5178.0"

~

~ -i LU

187.0

,,E m >,

194.5-

-=

203.4-

208.0

Tr

Late

Fig. 19.6. Jurassic-Cretaceous international time scale (after Harland et al. 1990, with permission of Cambridge University Press).

and 'Berriasian' in Boreal areas. The Jurassic-Cretaceous Boundary Subcommission has been at work on the problem. The Subcommission, for the present, recommends the use of the 'Boreal Berriasian' Stage rather than 'Ryazanian', and the retention of the Volgian Stage until there is precise understanding of the Tithonian Stage in Boreal Regions. The base of the Berriasian is now taken at the appearance of the Riasanites riasanensis Zone and the base of the Volgian at the base of the Ilovaiskya klimovi Zone. The latter corresponds to the base of the Late Kimmeridgian. Otherwise the standard Tethyan nomenclature, that of Harland et al. (1990), is used.

19.4.2

Aalenian. The earliest Aalenian zonal index Leioceras opalinum occurs with Pseudolioceras macklintocki in the Brentskardhaugen Bed condensed sequence. Also Brasilia aft. bradfordense indicates possible presence of the murchisonae Zone (B~ickstr6m & Nagy 1985). These faunas show open seaways to Europe and widespread correlation with the standard Tethyan zonal scheme.

157.1- ~

~

>,

Toarcian. The earliest probable /n situ Jurassic ammonite is Porpoceras polare which occurs in a partly phosphatised horizon 4 m below the top of the Wilhelmoya Formation at Rurikfjellet (Bfickstr6m & Nagy 1985, p.12). However, the oldest fauna is probably present, reworked in the Brentskardhaugen Bed, where Dactylioceras toxophorum suggests the presence of the falciferum Toarcian Subzone. The bifrons to thouarsense zones contain Porpoceras and Pseudolioceras spp. Pseudogrammoceras fallaciosum, the subzonal indicator for the late thouarsense Zone, and Pseudolioceras indicate later Toarcian deposits (see Frebold 1929a; Kopik 1968; Wierzowski, Kulicki & Pugaczewska 1981; B~ickstr6m & Nagy 1985).

3.0

Thurmanniceras 5.5 otopeta

.~

"-}

Carolineqettet

Prodeshayesites 12.5

132.0 w

, ~,,",

74--

Psudoaspidoceras flexuosurn

Barremian

__~

'~"~'=~

g.0

Neocardioceras juddii

Cenornanian

the standard Tethyan scheme. Ammonite zonation elsewhere in the Arctic was summarized by Callomon (1994).

Firkanten Fm

Pg ~aleocene Danian Maastrichtian

Svalbard units

369

Ammonite zonation

Ammonites form the basis of the Jurassic and Cretaceous biostratigraphy of the Adventdalen Group, which is summarized below. There are no major faunal breaks in the marine facies between Late Bathonian and mid-Albian time. However, the Barremian and possibly also the Early Aptian stage are represented by non-marine facies, so there is a faunal gap here. The sequence of zones recognised in Svalbard is given in Figure 19.7. At a time of regression, particularly Bathonian and TithonianBerriasian, the Svalbard faunas were strongly Boreal and particularly the ammonites which cannot be directly compared with

Bathonian. Because Boreal ammonites were so distinct from those further south during most of Mid-Jurassic time, there are considerable problems in defining the Bathonian stage in Arctic regions. A generic sequence, derived from the Bajocian Cranocephalites, commences in the Bathonian Stage with Arctocephalites and continuous through Arcticoceras to Cadoceras, and characterises these areas. (e.g. Callomon 1959, 1976, 1985; Imlay 1976). Some Russian workers considered Arcticoceras to be Early Callovian (e.g. Saks 1976). Callomon's zonal sequence is used here and is summarized below. Bathonian Cadoceras calyx Cadoceras variabile Arcticoceras cranocephaloides Arcticoceras ishmae Arctocephalites greenlandicus Arctocephalites arcticus Bajocian Cranocephalites pompeckji Cranocephalites indistinctus Cranocephalites borealis. The oldest Bathonian ammonite recorded from Svalbard is the dubious ?Arctocephalites from Svenskeya. Arcticoceras is now known from Spitsbergen and Kong Karls Land. A. harlandi from Kong Karls Land is closely comparable with the Arcticoceras species found in the lowest part of the A. ishmae Zone of east Greenland (Rawson 1982). Slightly younger Bathonian forms which occur in Spitsbergen are the Kepplerites of the tychonis-svalbardensis group. These probably indicate the lower part of the A. cranocephalites Zone of east Greenland. This fauna occurs immediately above the Brentskardhaugen Bed (Agardhfjellet Formation) in central Spitsbergen, but is preceded by the Arcticoceras fauna in southern Serkapp Land and Kong Karls Land. Hence the base of the Adventdalen Group appears to be diachronous.

Callovian. The 'standard' ammonite subdivision of the Callovian stage is shown in Fig. 19.7. In the Retziusfjellet Member on Kongsoya, Pseudocadoceras chinitense, P. grewingki and Cadoceras multicostatum date it as Early-Mid-Callovian (Lofaldli & Nagy

370

CHAPTER 19

STAGE

PERIOD

Alblan

Aptlan

AMMONITE

BIVALVE

FORAMINIFERA

DINOFLAGELLATE

Euhoplltes Dlmorphoplltes & Inooeramus angllous lautus Gastroplltes beds beds Hoplltes H. Svalbardensls dentatus & Grycla beds Douvlllelceras Otohoplltes marnmlllaturn beds Leymerlella Leymerlella aoutloostata sz tardefuroata Leymerlella schrammenl sz I. spltsbergensls/ Tropaeum arotlcum beds lablaflformls beds

Pseudoceratlum polymorphurn beds

1

O uJ O

_>. s_ ~3

uJ

Hauterlvlan

Slmblrskltes dechenl Speetonlceras verslcolor

Valanglnlan

Dlohotomltes spp. Polyptychltes ramullcosta Temnoplychltes syzranlcus

Berrlaslan

To~rio & BoJarkla spp. beds Surltes spasskensls RJasan/tes rJasensls

14J

O

Tlthonlan

d) Klmmeridglan

Oxfordlan

Callovlan

O CO

< rv

Gardodlnlurn ordlnale beds

Barremlan

~) -"O "(3

Bathonlan

Inooeramus off. auoella/ I. sp. ex ~Ir. oolonlcus beds Buchla crasslcolls? Buchla sublaevls Buchla keyserllngl 'l Buchla Inflata Buchla volgensls Buchla okensls

Craspedltes nodlger Craspedltes okensls Vlrgatosphlnctes spp. Buchla russlensls Laugeltes groenlandlcus Dorsoplanltes maxlmus Buchla rugosa Dorsoplanltes panderl Buchla mosquensls Subplanltes/Peotlnatltes spp. ?Aulacost. autlsslodorensls Buchla tenulstrlata A. koch/ s.z. A. koch/ A. norwe~}Icurn s.z A. kltchlnl A. rnoclestum s.z. A. subkltchlnl s.z. Buchla concentrlca Amoeboceras bauhlnl Amoeboceras rosenkrantzl Amoeboceras regulare Praebuchla lata ................. Amoeboceras serratum Arnoeboceras glosense Cardloceras cordaturn Quenstecttooeras rnarlae Quenstecltoceras lamberfl Longaevlceras nlkltlnl Cadoceras apertum Retroceramus spp. Cadoceras calyx beds Kepplerltes lychonls Arctlooc. cranocephaloldes Arctlcoceras Ishmae

Increase In Haplophragmoldos sp. & Trochamrnlna sp.

Nelchlopsls kostromlopsls beds

Glomosplra sp. & Glomosplrella sp. beds

Gaudrylna aft. miller~

Ammodlscus zaspelovae Trochammlna rosaoea

Haplophragmoldes canulformls

Reourvoldes dlsputabllls

Trochammlna rostovzevl

Crussolla deflandrel -Wanaea flmbrlata Llesberglo soarburghensls -Waneo hysanota Melourogonyaulax planosepTa -Chlamydophorella ectotabulata Slrrnlodlnlum gross// Nannoceratopsls graollls

--3

BaJoclan

Aalenlan

>,

Toarclan

Pseudolloceras rnackllntockl Leloceras opallnum Pseudolloceras rosenkrantzl Pseudolloceras polare

Dodokovla bullula -Nannocoratopsls senex Mlkrocysta erugata

0 l.U Pliensbachlan

SRAI' Fig. 19.7. Summary of the biozonal schemes for Svalbard and the adjacent Barents Sea, largely after Smelror (1994) for Jurassic; ammonites after Owen (1988), Nagy (1970), Yershova (1983); bivalves after Surlyk & Zakharov (1982), Kelly (in Arhus, Kelly et al. 1990), including new data; foraminifera, Nagy et al. (1990); dinoflagellates, Smelror & Below (1991), compiled by S. R. A. Kelly.

1980). Callovian faunas have been found on Spitsbergen and Kongsoya which have all yielded Longaeviceras and Quenstedtoceras (?Eboraciceras) species of Late Callovian (probably athleta to lamberti zone) age.

Oxfordian. Standard Oxfordian ammonite zonation (Fig. 19.7) is based on a combination of Boreal (cardioceratid) and Tethyan ammonites. The cardioceratid zonation for the Mid- to Late Oxfordian is that of Sykes & Callomon (1979) based principally on faunas from northern Europe and Greenland. Yershova (1983) summarizes the sequence of ammonites from central and southern Spitsbergen and Kong Karls Land. But the names used should be treated with caution. Other significant articles are by Frebold

(1930a), Pchelina (1967), and in Kong Karls Land (BliJthgen 1936; Smith et al. 1976). The Early Oxfordian zones are represented by Quenstedtoceras mariae and Cardioceras cf. cordatum (Yershova 1983). The MidOxfordian is not so clearly recognisable in the 'Amoeboceras alternoides' assemblage, which may be Early-Mid-Oxfordian, is more widely recognised particularly from the A.regulare and A. rosenkrantzi zones

Kimmeridgian. The extension of the Volgian stage down to the base of the Subplanites zones of the Soviet Union (Pectinatites zones of Western Europe) means that the base of the Volgian stage corresponds with the base of the Tithonian stage and that the 'Late

JURASSIC AND CRETACEOUS HISTORY Kimmeridgian' of earlier British authors falls in the Tithonian stage. The Kimmeridgian Stage thus now consists of only the previous 'Early Kimmeridgian' zones (Fig. 19.7). In the most northerly regions the Kimmeridgian faunas are dominated by cardioceratids, and Russian and Polish authors (e.g. Pchelina 1967; Saks 1976; Birkenmajer, Pugaczewska & Wierzbowski 1982; Wierzbowski 1988) regard Amoeboceras (Amoebites) as characteristic of the earlier Kimmeridgian and Amoeboceras (Hoplocardioceras) as typifying the later Kimmeridgian stage. In Svalbard, Kimmeridgian faunas are widespread (e.g. Frebold 1930a; Pchelina 1967; Birkenmajer et al. 1982; Wierzbowski 1988). Earlier Kimmeridgian Amoeboceras (Amoebites), of the kitchini group are common, but definite later Kimmeridgian ammonites (Euprionoceras cf. sokolovi and Hoplocardioceras cf. decipiens) are recorded only from two localities on Spitsbergen. A Xenostephanus from Kongsoya may belong to the cymodoce or mutabilis zones but there is no evidence of the highest two zones of the Kimmeridgian Stage.

Tithonian (Volgian). As a stage name, Tithonian is preferred to Volgian because it is more globally widespread and based on Tethyan rather than Boreal faunas, so serves better as a standard for correlating northern and southern hemispheres (Harland et al. 1990). However, the zonal sequence applicable in Svalbard approximates to the type Volgian sequence of the Russian Platform with elements of the northern Siberian zones. Work to correlate these internationally remains to be done. Seven Volgian ammonite asssemblages/zones have been differentiated in Svalbard by Yershova & Pchelina (1982): Late Volgian

Craspidites nodiger Craspidites okensis Strata with Virgatosphinctes spp. and Buchiafischerina Mid-Volgian

Laugeites groenlandicus Dorsoplanites maximus Dorsoplanites panderi Early Volgian Strata containing Pectinatites spp. and Subplanites sp. The ammonites of the Svalbard Volgian show a progressive change from Early Volgian forms that are more Tethyan, through to the distinctly Boreal Late Volgian craspeditids. The sequence is most similar to that of the Russian Platform and N. Siberia. The Early Tithonian (Early Volgian) is represented by the appearance of Pectinatites and Subplanites. The Middle Volgian is characterised by Dorsoplanites, Laugeites, Pavlovia and Zaraiskites. The beginning of the Late Volgian is marked by the appearance of Virgatosphinctes and is followed by Craspedites.

Berriasian. The Berriasian Stage was defined at the base of the Cretaceous Period in the Tethyan province. It covers the Boreal Ryazanian Stage, which is more applicable in Svalbard as the ammonite fauna is similar to that of eastern Greenland, arctic Canada, England, N. Siberia and the polar Urals. The Ryazanian Stage is divided into two zones in its type area on the Russian Platform:

Surites spasskensis Riasanites rjasanensis. An earlier Chetaites sibiricus zone is present in northern Siberia and the northern Urals (Saks & Shulgina 1974). Because of the paucity of ammonite finds in Svalbard, the differentiation of the Berriasian Stage is not as clear as in Russia. No fully authenticated Early Berriasian ammonites have been found on Svalbard. Chetaites cf. sibiricus probably indicates the Chetaites sibiricus Zone (Yershova 1972a) and the rjasanensis zone may be indicated around Isfjorden by a possible Riasanites? cf. rjasanensis from the Agardhbukta area (Zhirmunskiy 1927) which although figured has not been subsequently confirmed. The Surites

371

spasskensis Zone is represented on Spitsbergen by Borealites, Surites, Praetollia and Tollia (Yershova 1972a).

Valanginian. The Boreal Valanginian fauna is similar to that of eastern Greenland, arctic Canada and Novaya Zemlya (Yershova 1980). It is characterized by Temnoptychites, Polyptychites, Europtychites, Astieriptychites and Neocraspidites. The stage boundaries are well defined, but correlation with the Tethyan zones is not yet possible. Two local zones can be recognized in Spitsbergen (Yershova 1980): Polyptychites ramulicosta and Temnoptychites syzranicus. The upper Polyptychites ramulicosta Zone fauna includes the following species: P. aft. ramulicosta Pavlow P. cf. rectangulatus Bogoslovsky Euryptychites aft. pavlovi Voronets Astieriptychites cf. astieriptychus Bodylevsky Neocraspedites gratissimus Yershova N. mirus Yershova N. aft. mirus Yershova. The lower Temnoptychites syzranicus Zone contains:

Temnoptychites (Russianovia) borealis Bodyl. T. bodylevskiyi Yershova. Hauterivian. The stratigraphy of the earliest Hauterivian of the Boreal realm is poorly known, but the late Early Hauterivian zone of Speetoniceras versicolor and the Late Hauterivian Simbirksites decheni zone are well represented in Arctic regions and can be recognized in Svalbard (Pchelina 1965; Yershova 1972b). Their correlatives in northwest Europe are also characterised by simbirskitids, but few are found in Tethys, so exact correlation of the Boreal Hauterivian/Barremian boundary is not yet possible. Barremian. No Barremian ammonites are known. Deposits in the interval are of non-marine facies.

Aptian. Late Aptian ammonites (Tropaeum arcticum) appear in the lower part of the Carolinefjellet Formation and continental deposition may have continued into Aptian time in Svalbard.

Albian. Nagy (1970) reviewed the occurrence of Albian ammonites in Svalbard and recognised six successive ammonite faunas which he correlated with the Albian Stage of northwest Europe. The earliest Albian ammonite recorded was Proleymeriella sp. indicating the early part of the tardefurcata Zone. Owen (1988) identified this as representing the schrammeni subzone. In the overlying faunas of Arcthoplites jachromensis (Nikitin) and A. birkenmajeri Nagy, Owen recognized the acuticostata Subzone from the presence of Leymeriella germanica Casey, Freboldiceras remotum Nagy and F. sigulare Imlay. After a faunal break the next ammonites including Otohoplites and some Grycia represent the later part of the mamrnillatum zone. The appearance of the MidAlbian is indicated by the Hoplites fauna with Grycia, which is placed in the earlier part of the dentatus Zone. The later dentatus and lautus zones contain Dimorphoplites, Euhoplites, and Gastroplites. No Late Albian fossils are known.

19.4.3

Belemnite ages

Doyle & Kelly (1988) have shown that the Mid-Jurassic to Early Cretaceous belemnites of Svalbard belong to the Arctic belemnite province of the Boreal realm, having affinities with those of other Arctic regions, although some taxa are common to the northwest European fauna as well. Stratigraphic ranges of the various species

372

CHAPTER 19 The evidence, particularly from bivalves, concerning the presence of the Bajocian, Bathonian and Callovian stages (B~ickstr6m & Nagy 1985) in the Brenstskardhaugen Bed is equivocal.

~.~o

~o~o

Barremion Hauterivian Valanginian Berriasian

I I Ill I I

I I

Tithonian/Volgian

19.4.5

Microfossils

Foraminifera. Arenaceous foraminifera were used by Nagy et al. (1990) to establish 8 foraminiferal zones of Oxfordian to Berriasian age in the Janusfjellet Subgroup (Fig. 19.7). They are also of stratigraphic use in the Passet Member of Kongsoya which has now proved to be of Aalenian/Toarcian age on the basis of foraminiferal assemblages (Lofaldli & Nagy 1980). Calcareous foraminifera have only been recognised significantly at two horizons in the base of the Rurikfjellet Fm (the Wimanfjellet Member) of Berriasian age in Central Spitsbergen; and in the Tordenskj61dberget Member (Valanginian) of Kong Karls Land. From the submarine sections, formal Callovian to initial Cretaceous biostratigraphic zonations have been proposed (Smelror 1994).

Kimmeridgian Oxfordian Callovian Bathonian Bajocian Aalenian Toarcian

Fig. 19.8. Biostratigraphic distribution of belemnite genera in Svalbard. Solid bar indicates Svalbard occurrence; open bar indicates non-Svalbard occurrence (after Doyle & Kelly 1988). have been established in Kong Karls Land where they have proved particularly useful in the correlation, confirmation and refining of ages of the members of the Janusfjellet Subgroup. Only Lenobelus is Early Jurassic, it continues into the Mid-Jurassic where Paramegateuthis, Pachyteuthis, Cylindroteuthis also occur, the last two continuing into Late Jurassic where Lagonibelus appears. The initial Cretaceous Acroteuthis and Pachyteuthus continue through Berriasian into Valanginian and Hauterivian, which are marked by diversification and addition of Hibolithes and Cylindroteuthis (Arctoteuthis). With the exception of Hibolithes which is of Tethyan ancestry, the bulk of the genera are Boreal with strong specific links to other Arctic faunas. The principal belemnite descriptions were by Blfithgen (1936), Birkenmajer, Pugaczewska & Wierzbowski (1982), Doyle & Kelly (1988). The distribution of Svalbard belemnite genera is shown in Fig. 19.8. 19.4.4

Bivalves

The sequence of the marine bivalve Buchia is of biostratigraphic importance in Boreal Callovian-Hauterivian strata. In the absence of ammonites, and particularly in Svalbard, this allows correlation and dating at substage level. A zonal scheme was established by Zakharov (1981) for Siberia and the Russian Platform. Most of the zonal species are recorded from Svalbard and the Buchia zones recognized are shown in Fig. 19.7 and have been identified from published sources. Correlation can now be achieved between Svalbard and East Greenland (Surlyk & Zakharov 1982), Andoya, Lofoten Islands, Norway (Zakharov, Surlyk & Dalland 1981) and Europe (Kelly 1990). The earliest Buchia recognized in Svalbard is B. concentrica (J. de C. Sowerby) which ranges through Oxfordian-Kimmeridgian strata; B. russiensis characterizes the late Mid-Volgian. B. okensis and B. volgensis are particularly important for recognising the Berriasian Stage and recognising the Jurassic-Cretaceous boundary. The Buchia keyserlingi-sublaevis complex in the Valanginian and early Hauterivian concludes the history (see Fig. 19.7 for further zonal species).

Microflora support and in some places refine, dating based on ammonites. Marine microplankton from the Janusfjellet Formation have been studied and compared with those described elsewhere from northwest Europe and the Canadian Arctic by Smelror (1988) and in Kong Karls Land by Bjaerke (1977, 1978, 1980a, b). Stratigraphic ranges of dinoflagellates have been established, ranging from Hettangian-Toarcian (Smith et al. 1976; Bjaerke & Dypvik 1977) and ?Late Bathonian/Callovian to Hauterivian age (Fig. 19.7). Bjaerke recognized two assemblages within the Rurikfjellet Formation (1978) and three in the Agardhfjellet Formation (1980). Grosfjeld (1991) recognized that the uppermost Retziusfjellet Formation contained Barremian dinoflagellates. Smelror gave local stratigraphic ranges for dinoflagellate cysts and acritarchs in the Toarcian-Aalenian Passet Member and the Late Bathonian-Oxfordian Retziusfjellet Member and established the existence of a non-sequence at the top and base of the Retziusfjellet Member. Arhus (1991) described the dinoflagellate cyst stratigraphy of southeast Spitsbergen and the Barents Sea, although he fell short of establishing a formal zonal stratigraphy for the Early-Mid-Albian. He confirmed a late MidAlbian age for the Sch6nrockfjellet Member, the taxa are comparable to forms from northern Europe. From the Barents Sea Smelror (1991, 1994) proposed a formal Toarcian to Oxfordian dinoflagellate zonation (Fig. 19.7). Coccoliths. These have been useful locally, but a broader study covering the whole of Svalbard is needed. Verdenius (1978) argued a Valanginian age on the basis of coccoliths for the Tordenskjoldberget Member of Kong Karls Land, which was in agreement with the previous age attribution on molluscs.

Plants are useful in the Helvetiafjellet Formation where there are no marine fossils. Similarities have been noted in the Early Cretaceous floras of Spitsbergen, Franz Josef Land and the USSR by Vasilevskaya (1980, 1986), who dated the formation as Barremian-Early Aptian. 19.4.6

Jurassic-Cretaceous correlation in Svalbard

The correlation of the principal lithostratigraphic units on Svalbard and the adjacent Barents shelf is summarized in Fig. 19.9. 19.5

Jurassic-Cretaceous formations

The strafigraphic scheme is followed here, formation by formation, as concluded in section 19.3 which was based on mappable units and their classification and nomenclature. In this section their age and genesis are discussed. As a preliminary indication of age of the formations Fig. 19.7 plots against a time-scale the positive biostratigraphic evidence of age. The nature of each of the formations

JURASSIC AND CRETACEOUS HISTORY

MA

STAGES

SPITSBERGEN

56.5 6o.5

WILHELM4~(A

373

SVENSKGWA

KONGSOYA

HOPEN

BJORNOYA BASI N

Firkanten Formation

Thanetian

-60 65

Danian

- 70

Maastrichtlan

74 Campanian -80 83 86.5

Santonian

I

88.5 - 9o 9o.5

II

II 9i

Coniacian Turonian

II

Cenomanian 97 - 100

L

Albian -

M

110112

E

hfnrockfjellet Mb ZIIlerberget Mbr , [ - ~ Langstakken Mbr Innkjegla Mbr

L Dalkjegla Mbr Aptian

- 120

124.5

E

- 130 132 135

Barremian

_=,Festnlngen Mbr

WWWvVV

Hautedvlan

140.5 Valanginian - 140

150152.1 157.1

Tordenskjoldberget Mbr unnamed units

"lithonian Slottsm~ya Mbr

154.7 Klmmeddgian Oxfordian

-160161.3

?

Mbr (Mycklegardt]~ Bed)

Berdasian

145.6 -

El Managrem :~ Mbr

Glitref]ellet Mbr

O p p d a l s ~ t a Mbr

Dun6rt]ellet

Lardyfjellet Mbr

Callovian

Mbr

L

Retziusfjellet Mbr

Bathonian M

166.1

E

-170

3 Dmnbreen Bed 2 Marhegda Bed

Bajocian

1 Brentskardhaugen Bed

173.2

Passet

Aalenian

178

Mbr

-180 Toarclan 187 -190

~llensbachian 194.,=

i Smallega I Knorringfjellet Mbr Mbr

Tumlingodden Mbr

Sinemudan

- 200 203.,= 208 _210209.,=

Fig. 19.9. Summary of the Jurassic and Cretaceous stratigraphy of Svalbard and the adjacent Barents Sea (devised by S. R. A. Kelly).

Hettanglan

?

?

WVVWVVV

?

?

Mohnh~gda Mbr

Sjegren~ellet Mbr

Lyngofjellet Mbr

Kapp Koburg Mbr

Flats~en

?

Rhaetian

Bj~mbogen Mbr -220

[

Norian Tvillingvatnet Mbr

223

is discussed in sedimentary terms and the igneous component is separated to the last subsection.

19.5.1 Wilhelmoya Formation (Worsley 1973) The Withelmoya Formation spans the Triassic-Jurassic boundary. Its main description is in Section 18.3.3 of the previous chapter. Now that the Brentskardhaugen Bed is classified (here) at the base of the Agardhfjellet Formation the possible range of Jurassic strata in the Wilhelmoya Formation appears to be limited to the East Svalbard Platform. Unfortunately, the Jurassic strata listed by Klubov (1965a) on Wilhelmoya appear to be displaced. Therefore the principal information comes from the Mohnhogda and Sjogrenfjellet members on Kongs Karls Land, with Rhaetian, Hettangian and Sinemurian and possibly as late as Toarcian ages. Mention of Toarcian ages may appear to confuse the matter, because derived Toarcian fossils are abundant in the Brentskard-

haugen Bed which are, thus, interpreted as the result of erosion or winnowing of phosphatic concretions from the Wilhelmoya Formation. The Brentskardhaugen Bed is well established as Bathonian so that the Wilhelmoya Formation, before erosion, could have extended through the Liassic interval.

19.5.2 Janusfjellet Subgroup (Parker 1967) Re-establishing the Janusfjellet unit as a subgroup permits it not only to be constituted by the defining Agardhfjellet and Rurikfjellet Formations in Spitsbergen, but also to include the Kongsoya Formation in Kong Karls Land. These rocks, comprise a quite distinctive shaly package in which the Brentskardhaugen Bed seems to be accepted at the basal conglomerate of the Agardhfjellet Formation, rather than the top of the Wilhelmoya Formation. The top of the Subgroup is even more clearly defined where the resistant sandstone of the Festningen Member of the Helvetiafjellet

374

CHAPTER 19

F o r m a t i o n overlies the Rurikfjellet F o r m a t i o n . T h e following d e s c r i p t i o n a n d i n t e r p r e t a t i o n d e p e n d s largely o n D y p v i k e t al. (1991a, b).

Agardlffjellet Formation (Parker 1967) (40 to 290m). This unit, formed under shallow-marine shelf conditions, was dominated by clay. However, sand bodies were redeposited from earlier deltaic sediments. The shales were partly formed in anoxic conditions. The delta front was advancing in a NE-SW line from the northwest (Dypvik et al. 199 lb). The formation is rich in ammonites representing Callovian, Oxfordian, Kimmeridgian and Volgian stages. It is divided into four members. (1) Oppdalen Member (Dypvik et al. 1991a) comprises three beds: Brentskardhaugen Bed (Parker 1967), 0 . 2 - 4 m (1.3m at the eponymous locality). This 'Lias conglomerate' at the base has attracted much discussion, quite apart from the purely conventional matter as to with which formation it should classed. It is a widespread and easily recognizable horizon. It is a remani6 unit with pebbles which are phosphatic concretions containing i.a. Toarcian bivalves and ammonites and younger fossils ranging up to late Bathonian age. Its origin has been discussed many times. The pebbles are of phosphorite, quartzite and chert usually in a matrixsupported texture of well cemented sandy material and thus forms an easily mappable unit. The biota has been recorded by Wierzbowski, Kulicki & Pugaczewska (1981) and B/ickstrrm & Nagy (1985) who investigated the lithology and fauna. The clast fossils range from Toarcian to at least Aalenian while the matrix appears to be late Bathonian. Maher (1989) suggested a storm related origin. The Marhogda Bed (B~ckstrrm & Nagy 1985) (0.3 1.5m) follows with oolitic, glauconitic to chamositic sand/siltstone facies (Dypvik et al. 1991a). The Dronbreen Bed (Dypvik et al. 199 l a), 10-60 m is a sequence of loosely cemented sediments (sand, silt and clay). Lack of structure may indicate bioturbation. The main transport direction is suggested (Dypvik et al. 1991a) as towards S to SE. It is rich in ammonites, belemnites, bivalves, and foraminifers (Dypvik et al. 1991a). (2) Lardyfjellet Member (Dypvik et al. 1991a) 35 m. This member typifies the Agardhfjellet Formation of dark grey to black shales and paper shales, with common carbonate concretionary beds. The paper shales are rich in organic material, but are not fossiliferous; otherwise bioturbated sediments are a minor component. The grey shales are rich in fossils (bivalves, ammonites including Kepplerites, and belemnites). The concretions are dolomitic. (3) Oppdals~ta Member (Dypvik et al. 1991a) c. 225m appears as a siltysandy interval between the shaly members below and above. (4) Siottsmoya Member (Dypvik et al. 1991a) c. 100 m. This member resumes the typical facies of the Lardyfjellet Members with dominant grey shales and locally developed black and paper shales. In the upper part coarseningupward shale to sand sequences characterise horizons with Dorsoplanites. The upper levels contain the most abundant macro-faunas in the Rurikfjellet Formation. Concretions in the shales are typically red to yellow. Towards the top, light yellow concretionary (dolomite) beds dominate. Some of the thickness variation may be the result of Paleogene drcollement movement (Haremo et al. 1990). The post-Agardhfjellet pre-Rurikfjellet break.

N o t only does there a p p e a r to be a f a u n a l h i a t u s a n d a s e d i m e n t a r y d i s c o n f o r m i t y , b u t dolerite i n t r u s i o n s cut the lower f o r m a t i o n a n d are n o t k n o w n to p e n e t r a t e the Rurikfjellet F o r m a t i o n ( P a r k e r 1966, 1967). In western Torell L a n d the base o f the Rurikfjellet F o r m a t i o n is t a k e n at the base o f the P o l a k k f j e l l e t Bed ( B i r k e n m a j e r 1975). T h e age at this level is b e t w e e n Early K i m m e r i d g i a n a n d V o l g i a n ( B i r k e n m a j e r & P u g a c z e w s k a 1975). I n the east o f the C e n t r a l Basin the b r e a k at the base o f the M y k l e g a r d f j e l l e t Bed is b e t w e e n early Mid-Volgian and Valanginian (Birkenmajer, Pugaczewska & W i e r z b o w s k i 1982). It is t h e r e f o r e t e m p t i n g to d r a w a d i a c h r o n o u s b o u n d a r y for the base o f the Rurikfjellet F o r m a t i o n w h i c h y o u n g s eastwards.

Rurikfjellet Formation (Parker 1967) 40-290m. The Rurikfjellet Formation (Berriasian to Barremian) reveals an upwards-increasing sand content from the build-out of a delta system and partly reworked by storms. The delta front was advancing in a N-S line from the west (Dypvik et al. 1991b) Wimanfjellet Member (Dypvik et al. 1991a) is made of grey and partly silty shales, with some bioturbation. Lenticular concretions are reddish, sideritic

and up to a metre in diameter. Higher up their shape is spherical and they are composed of siderite and calcite. Bivalves, belemnites and occasional ammonites occur in lower concentrations than in the underlying formation. The Myklegardfjellet Bed (Birkenmajer 1980) 0.5-10 m forms the base of the Wimanfjellet Member in eastern central Spitsbergen. This clay unit is a distinct and widespread marker horizon often coloured reddish to yellow or greenish. It comprises two plastic-clay-rich horizons separated by grey shales. Glauconite occurs in variable concentrations. The clay carries some belemnites and foraminifers. The bed was deposited on a marine shelf and was subsequently altered by decomposition of its unstable glauconitebearing components. The event marks a change from predominantly shelf sedimentation controlled by global eustatic sea levels (Late Bathonian to Ryazanian) to a locally regulated deep sea to shallow shelf prodeltaic to deltaic mode (Ryazanian to Hauterivian) (Dypvik, Nagy & Krinsley 1992). This bed has been suggested as possibly containing distal ejecta from the (Mjolnir) impact in the Barents Sea (Gudlaugsson 1993; Dypvik et al. 1996). It has been dated at latest Tithonian to Early Berriasian from a shallow core 30 km outside the postulated crater rim (see Fig. 11.1 for location). Ullaberget Member (Rozycki 1959), comprises fine sands, silts and shales. In the south and at Festningen four coarsening-upward sequences were noted (Edwards 1976; Mork 1978) of 15 35 m totalling 85 m, generally hummocky cross stratification and bioturbation. Transport direction was towards the S and SE. Similar but less abundant fossils are found compared with underlying strata. The deposition of the Ullaberget sands is attributed to the progradation of the Festningen delta system. Uppermost Rurikfjellet Formation strata were investigated palynologically (Grosfjeld 1991). Dinoflagellate cysts indicated a Barremian age.

Kongsoya Formation (Smith et al. 1976) (see Kong Karls description in Chapter 5). The Kongsoya Formation is exposed in both main islands of Kong Karls Land: Svenskoya and in western and eastern Kongsoya. The successions differ in each outcrop area and reflect a time of minor tectonic instability. In Svenskoya to the west, the formation is represented by the Dunrrfjellet Member shale. In western Kongsoya, 30 km to the east three members were described, from the bottom: Passet (clay) Member. Retziusfjellet Member shale and Tordenskjoldberget Member limestone separated by disconformities. A further 25 km to the east in eastern Kongsoya the Nordaustpynten Shale Member is overlain by a poorly exposed unnamed unit. The Kongsoya Formation is included in the Janusfjellet Subgroup as an extension of it because of the dominant marine shale facies with belemnites. It differs from the two formations in Spitsbergen by its variability, its richly fossiliferous horizons especially limestones and most notably by its constituent lava flows which increase eastwards. It differs from the units below and above by its dominant marine argillaceous facies in contrast to their non-marine sandy facies. The Passet Member (Smith et al. 1976), 65 m is of clay, silt and little sand, with a conglomerate bed, clay ironstone nodules small belemnites and thin coal beds. Lofaldli & Nagy (1980) suggested that the middle and upper part of the member was deposited in a brackish environment; but the clay silt and belemnites suggest marine iagoonal conditions and indicate a Sinemurian to Toarcian age. Doyle & Kelly (1988) after a detailed study of the belemnites suggested a (?Toarcian), Aalenian, Bajocian age for the upper part. Dinoflagellates are consistent with Toarcian through Aalenian ages (Smelror 1988). Retziusfjellet Member (Smith et al. 1976), 75 m, is of black and grey shale with calcareous, ironstone or pyrite nodules, the calcareous concretions with ammonites, belemnites and bivalves, the whole suggesting formation in a marine inner shelf environment. Ammonites indicate ages from Late MidBathonian (ishmae zone) through Early and Mid-Callovian (e.g. Rawson 1982). Belemnites range through Kimmeridgian and (Volgian) Tithonian (Doyle & Kelly 1988). Dinoflagellate assemblages argue Late Bathonian to Early Callovian, then Callovian and in the upper part to middle Oxfordian ages (Smelror 1988). The discrepancy as to the Late Oxfordian through Volgian span may in part arise from the fact that these ages are represented in the Dun~rfjellet Member. Tordenskjoldberget Member (Smith et al. 1976), 30 m, comprises two equal divisions. The Lower division is a calcareous sandstone composed largely of prismatic fragments of the shell of the bivalve Inoceramus. It includes the 'Belemnite mounds' which are dated by Buchia as Early to Mid-Valanginian (Blfithgen 1936). Verdenius (1978) argued a Valanginian age from coccoliths and noted that a Valanginian to Barremian age had been suggested by Bjaerke. The belemnites and buchiids gave a clear Valanginian to Hauterivian age (Doyle & Kelly 1988).

JURASSIC AND CRETACEOUS HISTORY The Upper divisionof shales and siltstones has not provided evidence for age. Pchelina (pp. 60-64 in Krasil'shchikov 1996) abstracted Russian confidential reports on Mesozoic rocks. She noted i.a. that 'a peculiar metamorphic mineral assemblage with glaucophane, staurolite, kyanite and almandine, obtained from the Lower-Middle Jurassic deposits on Kongs Karls Land, and observed nowhere else in Svalbard, suggests that metamorphic rocks with glaucophane schists, probably associated with fault zones, may have been transported from the erosion area north and northeast of Kong Karls Land at that time'.

19.5.3 Helvetiafjellet and Kong Karls Land formations The Helvetiafjellet Formation is limited to Spitsbergen and the Kong Karls Land Formation to its own small cluster of islands nearly 200 km to the east. They have in common a non-marine sandstone and coaly shale facies following abruptly on the dominantly marine shales of the Janusfjellet Subgroup. They differ in that the Kong Karls Land Formation has conspicuous lava flows. But these cap the sequence above which nothing is preserved, whereas the Helvetiafjellet Formation is followed by the thick Carolinefjellet Formation. The two formations reflect a gently subsiding basin in Spitsbergen and a somewhat unstable shelf with lava flows in the east. In these respects, the Kong Karls Land Formation has similarities with the Franz Josef Land sequence, 400 km still further east.

Helvetiafjellet Formation (Parker 1967), 150m. Parker divided the formation into two members: the prominent massive sandstone Festningen Member below and the Giitrefjellet Member with more argillaceous interbeds above. The whole has been interpreted (Steel, Gjelberg & Haarr 1978) as an interdigitating deltaic facies with thick sets of cross-stratified, coarse distributary channel sandstones (which fine upwards), thin sets of ripple laminated siltstones, and interdistributary bay siltstones and clays, all generally with coarsening-upward sequences. A more detailed study of the Helvetiafjellet Formation by Gjelberg & Steel (1995) confirms a prior reduction of relative sea level with an angular unconformity slightly truncating Janusfjellet Formation strata. The formation itself reflects a fairly regular northwesterly transgression through Nordenski61d Land. The deltaic complex deposits thus retreated to the NW whence the sediments derived. The transgression probably reflects regular subsidence through Barremian time. There is no obvious correlation with the sequence stratigraphy and related sea-level curves as plotted in the Shell Geological D a t a Table, 1995, based on Haq et al. (1988). Indeed eustatic levels plotted insignificant change through this interval. In other words, as Gjelberg & Steel

Fig. 19.10. Summary of the lateral development of the Helvetiafjellet Formation (simplified by S. R. A. Kelly after Steel, Gjelberg & Haar 1984; Nemec et al. 1988a, b).

375

concluded, the formation shows 'the development of an overall retrogradational parasequence stacking pattern, interrupted by intervals of both aggrading and prograding parasequences'. In the south, where the thickness increases in this and the underlying unit, there is evidence of rotational collapse (in Festningen Member time) of Helvetiafjellet sandstones cutting into the Janusfjellet Formation with slide blocks, shaly and sandy turbidites (Nemec et al. 1988a, b). The slump structures measure up to 1.5 km horizontally and 50m deep into the underlying shales. They represent collapse of a delta front system (Fig. 19.10). Mork (1978) confirmed Challinor's conclusion that some rocks east of Hornsund, previously mapped as Triassic and Jurassic, are indeed Cretaceous. There was probably a confusion between the Kapp Toscana and Helvetiafjellet sandstones. This led to a revision of the thrust structures of Birkenmajer (1975).

Kong Karls Land Formation (Smith et al. 1976), 50m. The sandstones appear only to be preserved in the hill tops because of the overlying or interbedded protective lava flows 5-20m thick. The sandstones are not so resistant as those on Spitsbergen. Three members constitute the formation, one for each of the three outcrops. In each case they appear to rest unconformably on, and occasionally truncate, the underlying strata. In Svenskoya the formation, is represented by the Kiikenthalfjellet Member, (Smith et al. 1976), 65 m. At the base is a well consolidated, discontinuous brown sandstone, presumably a channel fill. The main body is of alternating sandstone, harder and softer and with intervening clay and carbonaceous material. Nearer the top are two beds of coal - one nearly 1 m thick. The sequence matches that of the Helvetiafjellet progression from Festningen through Glitrefjellet members. Two lavas occur at or near the top in contact or with thin sandstones between, and one connects with a sill. In western Kongsoya in the type section at Tordenskjoldberget in the Hhrfagrehangen Member, 14m. Similarly there are two lava flows at the top of the succession and sandstones with plant and tree trunk fossils and with thin coals. (Gothan 1907 described the flora). The sandstones are more conglomeratic. In eastern Kongsoya is the Johnsenberget Member, 50 m, with 20 m lava above 30 m sandstone and conglomerates. The island still further to the east, Abeloya, comprises blocks of basalt and dolorite not rising to more than 5 m above sea level. Because in Kongsoya the general dip is to east, it is likely that this island exposes the igneous rocks higher in the Kong Karls Land Formation as a quite distinct unit. The Helvetiafjellet and Kongs Karls Land formations show a progression eastwards, and possibly southeastwards, towards greater volcanic components. This is reflected not o n l y in the

376

CHAPTER 19

presence of lava flows in the Kongs Karls Land Formation, but in the volcanic content of the sediments. A plant-bearing tuffaceous horizon in the Kong Karls Land Formation may correlate with a tuff conglomerate east of Van Mijenfjorden where rounded andesitic pebbles up to 5cm diameter were recorded (Hagerman 1925). Similar horizons have been recorded elsewhere (Pchelina 1983). The composition of the sandstones has been investigated by Edwards (1978, 1979), Elverhoi & Bjorlykke (1978), Elverhoi & Gronlie (1981). In Spitsbergen the arenites have up to 95% to 25% mostly with a volcanic component. In Kong Karls Land quartz ranges from 50% down to 5%, the balance being volcanic fragments with feldspar and mica. Cement is quartz, calcite, illite or chlorite. The age of either formation, (Helvetiafjellet or Kong Karls Land) is not easily determined from contained fossils. In Spitsbergen, underlying strata are Late Hauterivian to Barremian and overlying strata are Late Aptian. There appears to be a stratigraphic break following the Janusfjellet sedimentation so the Helvetiafjellet Formation is most likely Barremian to Early Aptian. The Kong Karls Land Formation from internal palaeobotanical evidence is Valanginian or younger. Palynomorphs (Smith et al. 1976) include (presumably derived) Early Jurassic and (probably contemporaneous) Early Cretaceous forms. The lack of angiosperm pollen suggests an age not later than Albian or Cenomanian. Underlying strata constrain the age as Mid-Valanginian or younger. Thus a Barremian age is consistent with the evidence, but this is perhaps a convenient/conventional age. It could be Aptian or both. This conclusion was reinforced by Grosfjeld (1991) who reinvestigated constraints on the initial boundary of the Helvetiafjellet Formation. Dinoflagellate cyst species show that the youngest beds of the Rurikfjellet Formation are Barremian. From this it was concluded that no hiatus between the Rurikfjellet and Helvetiafjellet formations could be demonstrated as was previously thought.

19.5.4

Carolinefjellet Formation (Parker 1967)

The formation was thicker and more complete in the southeast partly because of the greater contemporary subsidence there, but mainly because Late Cretaceous tilting up to the NW led to successively deeper erosion to the N W so that 850m on the east coast are reduced to 200 m at Isfjorden, with a maximum of 1000 m (Fig. 19.11). The age ranges from Late Aptian through Albian. The base is almost transitional with the Helvetiafjellet Formation below, but is marked by the appearance of compact fine sandstones with well developed ripple and plane bedding laminations, and the disappearance of coaly shales; shales and mudstones may overlie the channel sandstones of the earlier formation. The top is always marked by the unconformably overlying basal conglomerate of the Paleocene Firkanten Formation. The overall environmental pattern is one of marine shelf sedimentation with facies ranging from tidal coastal to open shallow marine. Steel et al. (1978) recognized upward-coarsening sequences in the three sandier levels which suggest lower delta front facies developing delta lobe progradation. Both high and low energy environments are evident. Storm waves inducing bottom currents are indicated by cross-bedding. On the other hand, kerogen composition suggests shallow marine low-energy conditions with repeated phases of deltaic progradation and lobe abandonment marked by carbonate horizons (Bjoroy & Vigran 1979). Sediment source is from the north and northeast. Dropstones in fine-grained sediments have been taken to indicate ice rafting which is not inconsistent with a palaeolatitude of 65~ (Vincenz & Jelenska 1985; Frakes & Francis 1988). Dalkjegla Member (Parker 1967), 100m, is the equivalent of the Lower Lamina Sandstone of Hagerman (1925) and is best seen at Langstakken, 131 m. It is a fine, grey-green, often glauconitic,

Fig. 19.11. Fence diagram showing lateral variations in the Carolinefjellet Formation (after Nagy 1970).

JURASSIC AND CRETACEOUS HISTORY laminated to thinly bedded sandstones, with small-scale crosslaminations and alternating with dark grey-black shale and siltstone. Near the top is a conglomerate bed and locally there are carbonate concretions. The sparse fauna include ammonites, bivalves, scaphopods, ophiuroids and trace fossils. Innkjegla Member (Parker 1967), 430 m, is the Cretaceous Shale of Hagerman (1925). The type section is at Langstakken. Nagy (1970) distinguished a lower part of shale with lenses of clay ironstone and calcareous concretions and an upper fossiliferous shale-siltstone unit with beds of grey-green laminated sandstones and of clay ironstone. Chert and quartzite pebbles and boulders up to 50 kg weight are interpreted as glacial dropstones (Pickton 1981). Langstakken Member (Parker 1967), 178 m, is the 'Upper Lamina sandstone' of Hagerman (1925) and formed of grey-green, finegrained, platy cliff-forming sandstones with finer thin horizons. Bivalves, scaphopods and ammonites are scarse and poorly preserved. Zillerberget Member (Nagy 1970), 210m, is Parker's (1967) unnamed shale unit, comprising grey shale and siltstone with minor beds of grey-green fine-grained platy sandstone, and common clay-ironstone lenses. Bivalves and worm tubes (Ditrupa) are common; ammonites, gastropods and echinoderms less so. The formation is limited to southeast Spitsbergen. Sch6nrockfjellet Member (Nagy 1970), 83 m, is the upper sandstone member limited to south east Spitsbergen and of grey-green finegrained, well-bedded cliff-forming sandstone. Rare bivalve and crinoid fragments are found.

/12 ~

-81 ~

377 /15 ~

/18 ~

121~

124[

/ 5

--80 ~

~

~

'~'

oe

m,

0

...

,

Z9 o

~

Age of the Carofinefjeilet Formation. Marine faunas include ammonites, bivalves, gastropods, scaphopod, echinoids, crinoids, and range from Aptian to mid-Albian. The rich spore pollen assemblage at the base of the Dalkjegla Member at Festningen indicates an Early Aptian age and bivalves from the same member are also probably Aptian. Innkjegla Member faunas are Aptian to Albian. Five successive Albian ammonite assemblages were recognised by Nagy (1970). In the Dalkjegla Member are 'Crioceras' and Late Aptian to Early Albian spores. The Langstakken Member with Early Albian, Zillerberget-Early to mid-Albian ammonites and the Sch6nrockfjellet Member undated by ammonites but contained late Middle Albian dinoflagellates (.&rhus 1991).

IP

4' 7 7 ~

..

19.5.5

Jurassic-Cretaceous basic igneous rocks

Doleritic intrusions are abundant, especially in eastern Spitsbergen, the islands of Hinlopenstretet, Barentsoya, Edgeoya and Kongs Karls Land (Fig. 19.12). Lavas are known from Kong Karls Land. Sills may extend for 30km and range from 5 to 150m in thickness averaging 30-40m. They are often seen to be joined by thin dykes, 10-15 m thick. Only a weak differentiation is visible in the thickest sills. The petrography was described by Backlund (1907a, b) and again by TyrreU & Sandford (1933) who distinguished four main classes.

(A) Normal medium- to fine-grained facies constitute the main bulk of occurrences with a plexus of ophitic texture with plagioclase laths in a background of pyroxene and skeletal crystals of iron ore. The rocks are typically non-porphyritic and contain patches of imperfectly crystallised mesostasial matter. The large feldspars are bytownite and the smaller ophitic laths are An55 acid laboradorite. The pyroxenes approximate to enstatite-augite or pigeonite. Irregular areas of red non-pleochroic serpentine indicate former olivine. The skeletal ores are of titaniferous magnetite. The mesostasial matter is a fine complex of plagioclase laths, quartz, chlorite and pyroxene altered to brown hornblende and biotite with needles of apatite in an ill-defined base of alkali feldspar.

~-

U 0,,

km,

,

27 o

"

30 =

100

76 o /18 ~

121 ~

Fig. 19.12. Map showing the distribution of Jurassic-Cretaceous igneous rocks (sills and dykes) (based on Tyrrell & Sandford 1933, with permission of the Royal Society of Edinburgh).

(B) Coarse gabbroic and pegmatitic varieties exhibit fresh olivine and micro-pegmatite which may culminate in a pegmatite of quartz, hornblende and biotite with a nearly colourless (uniaxial) pyroxene. These late-formed groundmass pyroxenes are enriched in iron (towards hypersthene) and magnesium (towards enstatite). There is evidence of transformation from olivine to pyroxene and the olivine co-exists with quartz. Reddish biotite and deep greenish hornblende occur at the margins of the micropegmatite.

378 (C) sills and and

CHAPTER 19 Marginal varieties. Towards contacts with country rock of and dykes ophitic texture is lost in favour of an intergranular finely intersertial texture. Feldspar phenocrysts may develop olivine disappear.

(D) 'White trap' modification sills penetrating Triassic and Jurassic rocks prefer carbonaceous strata. The result is of fine magnesian minerals and even of feldspars by carbonates of calcium, magnesium and iron. This facies may account for Nordenski61d's 'hyperite'. Tyrrell & Sandford (1933) made a critical compilation of available chemical analyses and concluded with averages of selected work (Table 19.1). The differences between the two groups are probably not significant and the chemistry confirms the impression from field work that the same magma was responsible. Birkenmajer & Morawski (1960) described dolerite intrusions of Wedel Jarlsberg Land. Teben'kov, Burov & Vanshteyn (1980) reported that the rocks range in composition from porphyritic olivine dolerite (up to 13% olivine) to coarse-grained leucocratic gabbro~lolerite. The most widespread compositions are finegrained tholeiitic ophitic quartz dolerites with plagioclase 40-50%, pyroxene 35-40%, olivine 2-4%, quartz 1-8%, ore minerals 4-10% (mainly ilmenite and titano-magnetite). Intrusive contacts have fine-grained porphyritic facies with glassy patches. Wegand & Testa (1982) reported on the petrology and geochemistry of the Hinlopenstretet dolerites. The age of the intrusions was long debated. Tyrrell & Sandford (1933) concluded a range within Late Jurassic and Early Cretaceous. Parker (1966) observed pre-Cretaceous evidence of intrusions. Many are seen to cut Triassic strata, occasionally Jurassic and exceptionally Cretaceous Janusfjellet Sub-group strata. The youngest rocks to be cut are probably Berriasian. The intrusions could all be of that age or younger or spread through a much longer time span. The Kong Karls Land lavas are probably related and their ages can be determined approximately from fossils in the interbedded strata. Throughout Kong Karls Land, in Svenskoya and in western and eastern Kongsoya, lavas occur within the Kong Karls Land Formation of probable Barremian age. Earlier lavas are found in the east of the Kongsoya Formation down to the Nordaustpynten shale. Thus volcanism spread through Kimmeridgian to Barremian time. Moreover, it could have begun earlier in the east, where the lowest beds are at sea level, or later because the uppermost units in the Kong Karls Land Formation cap the hills (Smith et al. 1976). Isotopic determinations were first attempted (Gayer et al. 1966; Frisov & Livshits 1967) but with too little precision to have stratigraphic significance. The principal study by Burov et al. (1977) yielded 45 determinations from Isjforden, Storfjorden, Barentsoya, Edgeoya, Wilhelmoya and Nordaustlandet. Inspection of the list suggests that quartz-dolerites are typical of ages spread around

Table 19.1. Averages of chemical analyses ma&" by Tyrrell & Sandford (1993) in percentages

SiO2 AI203 Fe203 GeO MgO CaO Na20 K20 H20 TiO2 P202 MnO

4 Intrusive dolerites

4 Lavas

49.2 14.4 3.4 10.1 5.4 9.4 2.0 1.0 1.6 2.9 0.2 0.4

48.8 13.9 4.6 9.9 6.0 9.7 2.7 0.7 1.4 1.5 0.4 0.2

140Ma (?Tithonian to Hauterivian or Barremian) and younger olivine-dolerites range around l l 0 M a (?Aptian-Albian). Burov et al. concluded two maxima at 1444-5 and 105• 5Ma. More significant perhaps is their plot showing the older intrusions to be in Spitsbergen and the younger in eastern Svalbard. Analytical data were not given. Kovaleva & Burov (1976) published further details. Manecki (1987) reported prehnite in dolerite dykes in Wedel Jarlsberg Land. Birkenmajer (1979a) examined the thermal metamorphism of palynomorphs affected by the intrusions. Hughes, Harland & Smith (1976) had considered this as one factor in a wider problem to account for the poor showing of palynomorphs in some areas (see Fig. 20.6). Palaeomagnetic studies were reported by Spall (1968), Krumsiek, Nagel & Nairn (1968), Halvorsen (1973, 1974), Jelenska et al. (1978b), Aiinehsazian & Vincenz (1979), Vincenz et al. (1981), Vincenz & Jelenska (1985). In connexion with the palaeomagnetic work, further isotopic ages of 110 + 5 and 66.8 + 43 Ma were reported notably from dykes in the Vimsodden area of southwest Wedel Jarlsberg Land.

19.6

Jurassic and Cretaceous biotas

Marine and non-marine facies alternated so precluding a complete succession for either environment; but at the same time giving an impression of both land and sea. In a word this impression is commonly labelled 'Boreal', partly because the diversity of faunas appears to have diminished pole-wards so yielding faunas with many individuals and few species. However, this basic concept was challenged by Crame (1992), but does appear to work for the Jurassic and Cretaceous molluscs (Crame 1993). A further constraint on marine life and on its taphonony is the anoxic facies of the Janusfjellet Subgroup, in which environments limited life to a few adapted forms while at the same time protecting them from active predators. Preservational controls hinder indentifications. Faunas from mudstones are frequently crushed and easily weathered. Wellpreserved faunas are restricted to concretionary horizons which do not occur at all stratigraphic levels.

19.6.1

Marine biotas

The most evident biota, typical of all marine strata are molluscs: ammonites, belemnites and bivalves which not only contributed significantly to most collections of macrofossils, but provide reliable material for precise correlation. The ammonite succession is outlined in Section 19.4.2.

Ammonites, in so far as appropriate facies are available, occurred throughout, but often only as flattened impressions. Particularly good three dimentional preservation occurs in the Middle Jurassic calcareous concretions of Kongs Karls Land. They yield a typically Boreal succession with European affinities containing Toarcian through Albian species, with only the Bajocian stage unrepresented. Key ammonite papers are: Pompeckj (1899); Nathorst (1901); Stolley (1912); Spath (1921); Frebold (1929a, b,c); Bodylevsky (1929); Sokolov & Bodylevsky (1931); J. Weir (in Tyrrell 1933); Blfithgen (1936); Frebold & Stoll (1937); Rozycki (1959); Klubov (1965a); Pchelina (1965a, b,c, 1967); Kopik (1968); Yershova (1969, 1972a,b, 1980, 1983); Nagy (1970); Rawson (1982); B/ickstr6m & Nagy (1985); Kopik & Wierzbowski (1988); Weirzbowski (1988); Wierzbowski & Arhus (1990); Wierzbowski & Smelror (1993); Birkenrnajer & Wierzbowski (1991).

Belemnites are readily preserved and collected because of their durable calcite rostra, but require complete specimens to enable distinction of particular species from amongst the eleven genera or

JURASSIC AND CRETACEOUS HISTORY sub-genera known (Doyle & Kelly 1988). In contrasting preservation in the Brentskardhaugen Bed, it is usually only the phragmocones that occur. Species are listed in Section 19.4.3. Important earlier records include Lindstr6m (1865), Lundgren (1883), Sokolov & Bodylevsky (1931), Bltithgen (1936), Stoltey (1938). More recent records include Pchelina (1967), Birkenmajer & Pugaczewska (1975), Birkenmajer et al. (1982), Brckstr6m & Nagy (1985) and Doyle (1987). Ditchfield used Kong Karls Land belemnites for isotopic palaeotemperature studies (see Section 19.6.3 below).

Bivalves. The principal references are: Lindstr6m (1865); Lundgren (1883); Sokolov (1908); Sokolov & Bodylevsky (1931); Weir, (1933); Bliithgen (1936); Frebold & Stoll (1937); Soot-Ryen (1939); Birkenmajer & Pugaczewska (1975); Wierzbowski, Kulicki & Pugaczewska (1981); Birkenmajer & Pugaczewska (1982); Yershova (1983); Bfickstr6m & Nagy (1985). Brentskardhaugen Bed phosphatized sandstones contain the most diverse bivalve faunas of the Jurassic-Cretaceous sequences on Svalbard. The Toarcian-Aalenian and possibly up to Bathonian time interval is represented by byssate pteriids, pectinids, reclining oysters, shallow infaunal heterodonts, trigoniids and deep burrowing myoids which indicate well oxygenated and high energy conditions consistent with influence under storm-related conditions (Maher 1989). The Janusfjellet Subgroup mudstones have a less diverse fauna, usually of thin-shelled pteriids, including pectinids with sparse heterodonts and deep-burrowing lucinoids and myoids. Deposit feeding nuculoids are characteristic. Locally, fauna may be abundant, but forming low to medium diversity disarticulated valve assemblages. One distinctive assemblage from the Bathonian of Kong Karls Land is dominated by the inoceramid Retroceramus.cf, buluniensis (Koshchelkina). In Oxfordian-Hauterivian strata Buchia is particularly common. The Helvetiafjellet non-marine facies contain undescribed unionid bivalves. The return of marine condition in the Carolinefjellet Formation gave rise to relatively diverse benthic assemblages which have not been monographed.

Gastropods form a small element of the benthos.

Scaphopods as bottom dwellers are often preserved (some early records confused them with the worm Ditrupa).

Worms. Tubes of Ditrupa are common, Carolinefjellet Fm.

especially in the

Brachiopods are rare, even compared with more temperate biotas. Perhaps in the cooler waters they were still less able to compete with bivalves. Lingula cf. ovalis J. Sowerby and Discinisca sp. are cosmopolitan forms and were described with Ptilorhynchia sp. and Terebratulina sp. by Sandy (in Arhus et aL 1990), together with Cheirothyris sp. a more distinctive boreal form known from the Russian Platform.

Echinoderms are scarce: Crinoids, asteroids and ophiuroids were reported from the Carolinefjellet Formation (Nagy 1963).

Cirripedes. The plates are generally rare, but Zeugmatolepis? borealis Collins (in Arhus et al. 1990) was described from the Bjornoya Basin. Borings of Rogerella occur commonly in belemnite rosta (Doyle & Kelly 1988).

379

Corals are rare and only known from the occurrence of Thecocyathus from the 'Neocomian' of Kongsoya (Lindstr6m 1900). Stromatolites/oncoliths are recorded from the Willhelmoya Formation of southwest Spitsbergen (Krajewski 1992b). Foraminifers have been described (Lofaldli 1978, Lofaldli & Nagy 1980, Nagy & Lofaldli 1981; Nagy, Lofaldli & Brckstr6m 1988, Nagy et al. 1990). Agglutinated bottom-dwelling forams have a greater preservation potential than the more soluble planktonic forms and so most has been written about them. The faunas are well known from central Spitsbergen and in Kong Karls Land where the less consolidated sediments permit better preparation of material. (Fig. 19.7) Indeed, it is the agglutinated (quartz sand) forms which dominate. Lofaldli & Nagy (1980) reported low diversities. Four assemblages were named: two in the lower and two in the upper members of the Kongsoya Formation, but only the upper (Retziusfjellet Member) assemblages had ammonite control. One sample, only in the upper assemblage of the Retzuisfjellet Member, included three times as many species of non-agglutinated forams indicating their existence in the biota but poor chance of preservation. It may be significant that an investigation on the mainland of Spitsbergen showed that a richer agglutinating assemblage and the only calcareous assemblage were reported from the Rurikfjellet Formation (Nagy & Lofaldli 1981). This tends to confirm that the underlying Agardhfjellet Formation, with its sediments rich in organic carbon, inhibited the preservation of thin calcareous skeletons. Foraminiferal assemblages have proved useful mainly as environmental indicators in the Janusfjeltet Subgroup in Spitsbergen and Kong Karls Land (Bjaerke, Edwards & Thusu 1976; Lofaldli & Thusu 1977; Lofaldi & Nagy 1980, 1983; Nagy, Lofaldli & Brickstr6m 1988). Arenaceous foraminifera are predominant, generally indicating a neritic environment. Species diversity decreases with higher TOC levels, associated with increasingly anaerobic conditions. Calcareous species appear in significant numbers only occasionally, where there is increased availability of carbonate. This is associated with a more open marine environment, e.g. in the Tordenskjoldberget Member of Kong Karls Land (Lofaldli 1978). Foraminiferal mats form a distinct organo/sedimentary facies in the Wilhelmoya Formation in Van Keulenfjorden (Krajewski 1992a). Stromatolites. In the low sedimentation rate conditions of formation of the Brentskardhaugen Bed, Krajewski (1992a, b) records stromatolites in two forms. Firstly, they occur in association with foraminiferal mats as broad crusts. Secondly, they occur as oncolites in association with the phosphatised pebbles of the bed. These confirm formation under photic conditions, i.e. very shallow water. Vertebrates. There is no comprehensive review of Svalbard vertebrates, although Heintz (1964) summarized the occurrence of Jurassic reptiles. Saurians occur frequently as fragments in the Brentskardhaugen Bed (e.g. Wierzbowski, Kulichi & Pugaczewska 1981; Brckstr6m & Nagy 1985). Complete vertebrate remains are rare compared to the Triassic deposits. Woodward (1900) described a complete fish, Leptolepis nathorsti, from the Dun6rfjellet Member on Svenskoya and Ginsburg & Janvier (1976) record it as fragments in the Brentskardhaugen Bed of Lardyfjellet. Plesiosaurs have been most commonly reported: Tricleidus from the Lardyfjellet Member on Lardyfjellet (Callovian/Oxfordian) (Ginsburg & Janvier 1976) and at Sassendalen (?Oxfordian); and unidentified forms from the Oxfordian of Janusfjellet (Wiman 1913) and the Slottsmoya Member south of Deltaneset (Persson 1962). Calcareous nanofossils would be even less likely to survive but a Valanginian association of coccoliths was reported (Verdenius 1978) from the Tordenski61dberget Member.

380

CHAPTER 19

Dinoflagellates are a significant marine element and have some chronostratigraphic value (Fig. 19.7) (Bjaerke 1977; Bjaerke 1980a, b; Smelror & ,~rhus 1989; Smelror 1988; Arhus 1991; Arhus et al. 1990; Grosfjeld 1991). About 200 species have been identified from Kong Karls Land where the less consolidated strata afford superior preparation of samples.

Trace fossils. Although trace-fossils are widespread, especially in marine Jurassic and Cretaceous strata of Svalbard, there has been no systematic review or established ichno-facies scheme. However, ichnotaxa are frequently cited. Transgressive high energy sandstones, e.g. the Wilhelmoya Formation contain Arenicolites, Chondrites, Diplocraterion, Monocraterion, Rhizocorallium, Teichichnus and Thalassinoides, indicating high and moderate energy bottom conditions (B~ickstrrm & Nagy 1985; Worsley & Mork 1978; Krajewski 1992b). With deepening water in the Janusfjellet Subgroup, Chondrites and Muensteria become more characteristic in the silts to grey mudstones (Birkenmajer 1980). Locally bioturbation may be intense, homogenising the sediment, but in the black shale facies e.g. of the Lardyfjellet Member bioturbation is absent. Lithic hardgrounds are generally absent, but locally skeletal remains such as belemnites are hosts to Rogerella (attributed to boring barnacles) and ?Talpina (boring bryozoan) (see Doyle & Kelly 1988, e.g. pl. 8 fig. 10) in the Tordenskjoldberget Member of Kongsoya. The Helvetiafjellet Formation contains rootlet structures and some vertical traces possibly attributable to Skolithos (Edwards 1976a). Vertebrate trackways of dinosaurs occur in the Festningen Member (de Lapparent 1962; Edwards, Edwards & Colbert 1978). Doubtless a great variety of traces exists in the Carolinefjellet Formation from which Frebold (1931, p. 1.4, fig. 2) illustrated a sinuous trace on a rippled surface.

Temperatures of the ambient sea water have been the subject of comparative research in both Antarctic and Arctic biotas (see below 19.6.3)

19.6.2

Terrestrial biotas

Inevitably, the evidence for land-dwelling organisms depends largely on preservation of swamp accumulations.

Vegetation was earliest recorded in macroflora by Heer (1876); Nathorst (1897b, 1913); Gothan (1910, 1911) and Walton (1927). From these most subsequent accounts have been derived. Early records of 'Rhaeto-lias' flora should be treated as Triassic (see Chapter 18). Jurassic floras were claimed to show some uniformity of global environments (Seward 1931) and the best records are from MidJurassic strata especially in England and the Antarctic Peninsula). Only a small proportion of taxa has been recorded from Svalbard. Of these Seward tabulated (p. 343) the following with ranges thus: T, Triassic, J, Jurassic, K, Cretaceous. Equisetales Equisetites columnaris (etc.) Filicales Cladophlebis denticulata (etc.) Gleichonites Ginkgoales Ginkgoites Baiera Czekanowskia Phoenicopsis Coniferales Araucarites Pinites Podozamites

J TJK TJK TJK JK TJ J JK TJK TJK

The Early Cretaceous flora of Spitsbergen as described by Heer (1876), Nathorst (1897), Floris (1936), Vasilevskaya 1980, 1986 was based mostly on impression fossils mainly of Ginkgo, Elatides, Podozamites, Pinites (Pityocladus) and Pseudotorellia, with fragmentary remains of pteridophytes and very rare cycadophytes. Bose & Manum (1990), commenting on the above, showed that a revised taxonomy results from new laboratory methods to reveal the inner structure of seemingly unpromising material. A pilot study of 'Scidopytis'-like fossils demonstrated greater differences from modern analogues than was earlier suspected and a new family (Arctoityaceae) was established, which occasionally formed a dominant element in forests around 55 ~ to 65~ in Early Cretaceous time. This family can be traced back to middle Jurassic material. Jurassic and Early Cretaceous palaeolatitudes probably lay between 60 ~ and 70 ~ south of the present latitude. The problem is therefore not so much why the floras are poorer than in temperate latitudes, but how such luxuriant growth could survive the dark winters even if the global temperatures were more equable and warmer. This problem was, however, addressed by Spicer & Parrish (1966) for Aptian-Albian Alaskan floras. Deciduousness, not necessarily angiospermous, is one adaptation. Angiosperm origins may well be traced back through earliest Cretaceous and Jurassic time if we knew what to look for (Hughes 1994) but the obvious explosion in the evolution of flowering plants only becomes evident everywhere in Late Cretaceous fossils, as for example in West Greenland. But the lack of Late Cretaceous outcrops in Svalbard precludes the possibility of completing that story from our rocks. Thus, the change to the succeeding Paleogene flora is the more dramatic. Vertebrates. Dependent on the vegetation, vertebrates must have been a significant element amongst terrestrial animals. Remarkably the most notable is Iguanodon whose footprints in the (probably Barremian) Festningen sandstone at Festningsodden (Heintz 1963; de Lapparent 1962 have perplexed palaeobiologists as to how such a large animal could survive on vegetation at 60-70~ latitude with dark winters, whether by a store of body fat or migration. A dinosaur that wandered too far north accidentally is unlikely, because of the discovery of Allosaurus footprints in 1976, mentioned from south of Kvalv~gen on the southeast coast of Spitsbergen (Edwards, Edwards & Colbert 1978; Aga et al. 1986; Hjelle 1993, p. 41). It is arguable that footprints could do no more than distinguish bipedal herbivorous ornithopods (including Iguanodon 'Cretaceous') and bipedal carnivorous theropods (including Allosaurus 'Jurassic/Cretaceous'). However, different genera would not reduce the problem. Larger carnivores depend on other large-bodied animals and in turn on luxuriant vegetation. Little has been done to investigate in the supradeltaic and swamp deposits what other animals may have been around. Only molluscs are recorded including bivalves and the gastropod 'Lioplax" (Lundgren 1883; Sokolov & Bodylevsky 1931).

19.6.3

Jurassic and Cretaceous climates

The Cretaceous Period in particular is generally thought to have enjoyed warm climates. Many recent climatic simulation attempts have chosen Cretaceous data partly for this reason and also for the relatively wide accessibility of Cretaceous strata. Herman & Spicer (1996) in a study based on leaf physiognomy argued that the Arctic Ocean remained systematically above 0~ even in winter and so suggested that poleward heat transport must have obtained throughout the year. On the other hand ice transported stones, carried off beaches by thin sea ice has been reported from both Cretaceous and Paleogene sediments (Pickton 1981; Steel 1977). Blocks up to 50kg of chert and quartzite were recorded in the Innkjegla Member (Late Aptian-Albian). Small rounded clasts also occur in the Janusfjellet Subgroup close to the Jurassic-Cretaceous boundary.

JURASSIC AND CRETACEOUS HISTORY P. Ditchfield (pers. comm.) investigated stable oxygen and carbon isotopes (180 and 13C) from the carbonates in Jurassic and Cretaceous fossil shells in order to establish the ambient ocean palaeotemperatures in Svalbard. Three studies have been reported with average temperatures as below: From belemnites of Kongs Karls Land, Kongsoya Formation (Ditchfield 1997): Aalenian-Bajocian 12.7~ Mid-Bathonian-Kimmeridgian 9.4~ Early-Mid-Valanginian 7.7~ From belemnites in the Agardhfjellet Formation (Janusfjellet Subgroup) of western and central Spitsbergen (Ditchfield pers. comm.): ?Callovian (Lardifjellet Mbr) 16.6~ ?Oxfordian-Kimmeridgian (Oppdals~ta Mbr) 14.9~ ?Kimmeridgian-Tithonian (Slottsmoya Mbr) 7.6~ From bivalves from the Carolinefjellet Formation of Spitsbergen (Ditchield & Staley 1996): Early Albian (6.5-10. I~ 8.3~ They concluded a time of little or no glaciation. The general impression is one of cooling from warm Mid- and Late Jurassic to cooler Cretaceous temperatures. This, however, may not have been a global change, but quite possibly the narrowing or closing of a marine connection to the south.

STAGES TRANSGRESSION/ REGRESSION

MA h.,L

I

n

19.7.1

-e0

S5

i;

Oanian

19.7.2

Mid-Late Jurassic events (Bathonian-Tithonian)

This interval corresponds broadly to the record in the Agardhfjellet Formation in Spitsbergen and the Passet and Retziusfjellet members of the Kongsoya Formation. Throughout the outcrop areas, transgression leading to normal marine conditions prevailed in which deeper water, with deposition of muds, occasionally anoxic, occurred. Dypvik (1978) discussed

. . . .

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83

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100

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-1~32

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r4

Valanginian

~"

135

Biostratigraphic correlation is not sufficiently precise during the transition from Triassic faunas to suggest exactly where the boundary should be. However, the interval referred to here is that represented by the upper part of the (Rhaetian-Liassic) Wilhelmoya Formation. Indeed, whereas the earlier dating is obscure, the later dating is clear because the final consolidation of the Brentskardhaugen Bed was Bathonian. This interval is, thus, almost exactly Liassic, i.e. Hettangian through Toarcian. But there was a marked Toarcian marine flooding event. From the beginning of this interval the Billefjorden lineament was active in demarcating a positive area to the west, with little subsidence over a shallow marine shelf, whereas to the east subsidence was significant, although sedimentation kept pace in a deltaic environment so that thick mainly non-marine sands formed. Thus, during 30 million years an average of 30 m of strata were preserved in the west rising to 300 m in the east i.e. net relative sea level changes of 0.001 mm and 0.01 mm a -1 in rounded terms. The differential is significant, the magnitude is insignificant, it could be epeirogenic or eustatic. The sources of sediment were in the east. Evidence of the westward extension of the marine area is lost in the Paleogene orogeny. Evidence of any northward extent of Liassic deposits was removed by Late Cretaceous uplift and erosion (Fig. 19.13). From a study of coals, Michelsen & Khorasani (1991) showed that burial curves display a significant difference between Triassic and Jurassic-Cretaceous subsidence. The Jurassic-Cretaceous subsidence pattern is typical of extensional sedimentary basins, with stretching and cooling, whereas Triassic-Early Jurassic rapid subsidence terminated in a long period of no subsidence, except in the Eastern Platform.

...

:~.i.i:i.-....:.i:-.-.%1:-..!.-.:.i:..-...:.i:.-:.-:(:

- 7o

Jurassic and Cretaceous events in Svalbard Latest Triassic-Early Jurassic events (Rhaetian-Toarcian)

EVENTS I FACIES

I . . . . . . .

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19.7

381

/

145.61

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,

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~'".':'"~shelf 9..~.,...,- ,,,,,.,-

157.1 Oxfordian 1 -16o 161.3

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outer s h e l f

1~.1 ........_......__~ ~ . . ~ ! i : t 2

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Bajocian

173.5

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178

Aalenian

.~....~~ ~ ~ , ~

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194.5

-200

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208

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,

Fig. 19.13. Summary of events in the Jurassic and Cretaceous history of Svalbard (devised by S. R. A. Kelly). the carbonate component. The areas of subsidence reversed somewhat so that the thickest deposits formed west of the Billefjorden lineament. But a relatively stable environment continued with say 300m sediment preserved during the following 25 million years with a marginally greater rate of subsidence if 100 m of sea water be added say 1 mm in 60 years. (i.e. 1.6cm 1000 a-l). Coarsening-upward sedimentary cycles in the Callovian-Volgian were shown by Dypvik (1992a) to have average periodicities of 850,000 years comparable to Alpine Triassic Lofer facies carbonates. He estimated accumulation rates of 0.4-0.9 cm 1000 a -1 based on sections at Lardyfjellet and Oppdals~ta.

382

CHAPTER 19

The Billefjorden lineament continued as a significant control, not only defining the eastern margin of the Central Basin, but as an axis with thinner sedimentation. Similarly, but on less evidence, the Lomfjorden Fault Zone appears as a positive feature. Isopachs show that the Central Basin was also bounded on the west and probably by the persistent Kongsfjorden-Hansbreen Fault Zone or an incipient Palaeo-Hornsund Fault further west bounding north Greenland. Towards the end of this interval, igneous activity is evident. Dolerites intruded the Agardhbukta strata at the eponymous locality in Storfjorden (Gripp 1929) and in Torrell Land (Rozycki 1959), and are unconformably covered by Rurikfjellet strata. This is the youngest direct age in Spitsbergen for the ubiquitous intrusions, though pyroclastic sediments occur higher up (Parker 1966). This was accompanied by slight tectonic disturbance as there is evidence along the Billefjorden Fault Zone that the Agardhfjellet Formation was downfaulted to west and so preserved, but removed to the east. The Rurikfjellet Formation truncates this faulted unconformity (Parker 1966; Harland et al. 1974). The fault flanks an anticline which is also truncated so that further to the east the Agardhfjellet Formation again appears beneath the Rurikfjellet Formation. Along the axis of the fold the Rurikfjellet Formation rests directly on the Kapp Toscana Group strata. Figure 19.14, from Parker (1967), shows evidence for intraJanusfjellet Subgroup movements as further activity along the Billefjorden and Lomfjorden fault zones. This evidence was seemingly ignored in favour of Paleogene tectonic thickening on the same fault zones (Andresen et al. 1992; McCann & Dallmann 1996). Paleogene tectonic thickening of Mesozoic strata on these fault zones was perhaps first noted by Parker (1966). The Mjolnir (seismic) structure in the southern Barents Sea (approximately 29 ~ to 30~ 73~ ' to 74~ was interpreted as an impact crater (Gudlaugsson 1993). A drill core obtained by I K U 30km outside Mjolnir's rim showed anomalously high iridium, chromium and nickel concentrations which, together with shocked quartz grains, confirmed an impact event (Dypvik et al. 1996). The age of the strata rich in these components was estimated at late Volgian (Tithonian) to early Berriasian. The coeval Janusfjellet Subgroup was also tested for enrichment in Cr and Ni (which could also have a basaltic origin) and Ir. In each case these concentrations were systematically lower providing a standard background. The Myklegardfjellet Bed in Spitsbergen was said to be deposited at the same time.

recognised coarsening-up cycles with periodicities of 285 000 years comparable to Milankovitch orbital periodicities. Higher in the formation sedimentation rates increased further reflecting proximity of a coastline with high clastic input. Further igneous activity is evident in dolerite intrusions with a wide range of isotopic ages but with one peak at 144+ 5Ma, i.e. Earliest Neocomian (Burov et al. 1977).

19.7.4

The interval is represented by the Helvetiafjellet coarse prograding delta complex sandstones in Spitsbergen and the Kong Karls Land Formation with similar sandstones and basaltic lavas. Terrestrial facies spanned the whole Central Basin. Volcanic activity in the east extended westwards as seen in tufts and sediments with a high volcanic component. There is a distinct disconformity, even an angular unconformity, in Kong Karls Land at the base indicating the onset of more disturbed conditions. It is a short but a distinct episode with about 80 m preserved in the north and centre, thickening in south Spitsbergen to 150m during an interval of about 7.5 million years, i.e. 0.01-0.02 mm a -I . Contemporary instability of a delta front is seen in the slumping at the base of the Helvetiafjellet Formation of southeast Spitsbergen.

19.7.5

Aptian-Albian events

Up to 1000m (The Carolinefjellet Formation) is what is left from this interval of not more than 27 million years, roughly 0.04 mm a -1 . Aptian-Albian intrusive activity may have peaked in the east at 1 0 5 + 5 M a (Burov et al. 1977), and continued till at least 100 + 4Ma. This was a precursor to the Late Cretaceous regional uplift. A distinct basin developed bounded on the southwest by the Sorkapp-Hornsund High but without noticeable imprint of the Billefjorden Lineament. Sediment was derived from the north area which was rising.

19.7.6 19.7.3

Barremian events

Late Cretaceous (Gulf) events: (Cenomanian-Maastrichtian)

Neocomian events (Berriasian-Hauterivian) The record of Late Cretaceous events is not preserved in any formations in Svalbard, but rather in the erosion of pre-existing strata. Strictly this lacuna commenced in the Late Albian, sediments of which have not been recognized in Svalbard. Michelsen & Khorasoni (1991) believed that up to 1000m of Late Cretaceous strata were eroded, based on continued Aptian-Albian sedimentation rates.

This interval is represented by the extensive Rurikfjellet Formation in Spitsbergen. By and large the situation in the previous interval continued. Similar thickness of somewhat sandier facies are preserved in Spitsbergen, say up to 300 m in about 13 million years. Dypvik (1992a) gave an accumulation rate of 2.1 cm 1000 a -1 for the Valanginian in the lower part of the Rurikfjellet Formation. He

2~ $3

J

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re) . . . . . . . . .

Fig. 19.14. Lateral variation of the Agardhfjellet and Rurikfjellet formations across Spitsbergen (after Parker 1967, fig. 5, reproduced by permission of Cambridge University Press). The 'western fault belt' is the southern extension of the Billefjorden Fault Zone and the eastern is that of the Lomfjorden Fault Zone.

JURASSIC AND CRETACEOUS HISTORY

383

The most obvious event is the continued tilting upwards to the north or northwest so that the youngest Carolinefjellet strata are preserved only in the south and older members are truncated successively northwards by the sub-Paleocene unconformity. Just south of Isfjorden only the lowermost two members remain. Progressing northwards the Paleocene at Kongsfjorden eventually cuts down through the lowest Triassic formation into Permian strata. The average tilt is about 1 in 100 or 0~ '. The differential uplift at the latitude of Kongsfjorden compared with the uppermost Carolinefjellet Formation strata in the south is about 2.5 kin. This did not all happen in Late Cretaceous time as is evident from the earlier supply of sediments from the north. But supposing the tilting were limited to the 32 million years of Late Cretaceous time, it would represent a maximum average uplift rate of 0.05 mm a -] whereas if the uplift was spread over, say, the last 50 million years of Cretaceous time the rate would be 0.025 mm a -1 or approximately the rate of subsidence in the south. A consistent picture of relatively stable platform emerges subsiding differentially to the south and southeast through Jurassic-Cretaceous time at an increasing rate for 110 million years and culminating in the net uplift only at a similar rate in the last 30 million years. The Eastern Platform may well have continued to take on sediment, probably at a reduced rate, but the whole record has disappeared from Barremian time onwards. The argument that these epeirogenic changes, both subsidence and uplift, were the result of thermal expansion of the mantle was put forward for the whole Carboniferous through Cretaceous sequence of Svalbard (Harland 1969). A similar calculation for a hot spot in the centre of the British Isles gave quantitative results very similar to those adduced for Spitsbergen (Cope 1994). For Spitsbergen, however, the hot-spot, or more likely hot zone, was further to the north. Indeed it was the locus of the future fission

Figures 19.15a and b show mid-Jurassic and mid-Cretaceous palinspastic reconstructions respectively. The Jurassic frame reflects the beginning of Atlantic spreading by rifting, with Arctic events analogous to the initial Triassic rifting in the Appalachians from which latitude the Atlantic fission slowly extended northwards. These are the first indications of the break-up of Laurasia. The contemporary positions of the Russian far eastern block, east of the Verkoyansk orogenic zone and of the Alaskan terrane have been plotted according to the conclusions of a CASP Regional Arctic Programme study. The Cretaceous frame indicates that the Canada Basin had already been opened. The volcanism in Kong Karls Land and Franz Josef Land correspond to the initial mantle heating that was about to initiate sea-floor spreading in the Eurasian Basin along the Nansen-Gakkel Ridge. McWhae (1986) projected a tectonic history of northern Alaska, Canadian Arctic and Spitsbergen from Early Cretaceous time. D. G. Smith (1987) attempted a similar tectonic sequence of smallscale diagrammatic reconstructions (Pennsylvanian through Miocene). These have little impact on the interpretations in this work.

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along the Nansen-Gakkel spreading ridge and no doubt related to the Cretaceous magmatism. Worsley (in Aga et al. 1986) suggested that the differential uplifting to the north may have caused E-W faulting that had some control in the configuration of the present fjords. A case needs to be made. The diastrophic rate is very slight.

19.8 19.8.1

The tectonic frame

MID-CRETACEOUS

.P:ikol:msk ~ " ' V ~,-- . V - ~ - -

Svalbard in a Jurassic-Cretaceous regional context

Inyali-DebaBackArc Basin

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Fig. 19.15. Summary of structural and tectonic events in the Arctic in mid-Jurassic and mid-Cretaceous time, drawn by S. R. A. Kelly (after CASP Report 417; Dor6 1992; Rowley & Lottes 1988; Ziegler 1988).

Fig. 19.16. Jurassic to Cretaceous palaeogeographic maps of the Barents Sea. (a) Pliensbachian-Toarcian. (b) Aaleniant-Bajocian. (c) CallovianKimmeridgian. (d) Tithonian-Berriasian. (e) Valanginian-Huterivian. (f) Barremian. (g) Aptian-Albian. (ll) Late Cretaceous (modified by S. R. A. Kelly, after Kelly 1988). For Legend, see Fig. 17.15(a), p. 337.

Fig. 19.16. (continued).

386

19.8.2

CHAPTER 19

The sedimentary sequence

The shoreline during Jurassic and Cretaceous time appears to have been within the present area of Svalbard, with much of northern Spitsbergen and Nordaustlandet possibly emergent for most of this time. The dominant structural elements were two north-south trending fault belts running through eastern Spitsbergen, the Billefjorden and Lomfjorden fault zones and the Inner Hornsund Fault Zone of southern Spitsbergen. There was extensive igneous activity in Late Jurassic and Early Cretaceous time, with lava flows in Kong Karls Land and dolerite intrusion especially in eastern Svalbard. The Tertiary West Spitsbergen Orogeny subsequently folded these strata, with greatest deformation in the west. Smelror (1994) placed Jurassic stratigraphy of Svalbard in its western Barents Sea context. Eustatic changes were related to orogeny generally by Brookfield (1970).

Hettangian-Sinemurian. Thin marginal sediments were deposited on Spitsbergen and in the Hammerfest Basin (Olaussen et aL 1984) on the western Barents Shelf. Eastwards, the Pechora Basin and Novaya Zemlya formed relatively uplifted positive areas, with no sediments existing today. The Hettangian-Aalenian sequences in the western Barents Sea, offshore Troms area equivalent to the Wilhelmoya Formation, are represented by the Tubaen, Nordmela and lower Sto formations (Smelror 1994).

Pliensbachian-Toarcian (Fig. 19.16a).

Open marine conditions became widespread in the west and northern Barents Shelf, with transgression and subsidence in Spitsbergen and Franz Josef Land (Mikhailov 1979a). The Billefjorden Fault Zone was active, giving rise to condensed deposits to its west. The eastern shelf including the Pechora Basin remained positive. Smelror (1994) recognized initial Pliensbachian and early Toarcian cycle boundaries and another near the late Toarcian-Aalenian boundary.

Aalenian-Bathoniau (Fig. 19.16b).

Open marine conditions continued into Aalenian time in Spitsbergen and Franz Josef Land (Yefremova et al. 1983a, b), but by Bajocian time regression was widespread. During this regression, thick clastic sequences were deposited in basins offshore the Troms area (Smelror 1994). Although marginal marine conditions remained in the west, nonmarine sedimentation is regressed in the Syssol Formation of the Pechora Basin (Kravets et al. 1976) and on Andoya (Dalland 1981). However, transgression from Tethys had commenced, but had not reached the north. By Bathonian time, major eustatic transgression was occurring and open marine conditions returned in the western and northern Barents Shelf. The earliest phase of transgression is recognized as Mid-Bathonian on Kong Karls Land (Rawson 1982). The Bathonian through Volgian sequences of the Brentskardhaugen Beds and the Agardhfjellet Formation (Janusfjellet Subgroup) have their submarine equivalents in the Teistgrunnen Group. Further cycle boundaries were claimed in late Bathonian and early Oxfordian time (Smelror 1994).

Callovian-Kimmeridgian (Fig. 19.15c).

This is a time of major subsidence and marine transgression over the normally faulted and tilted blocks of the whole Barents Shelf and surrounding areas. The transgression had commenced in Bathonian time. The Pechora region subsided during Callovian time, so that for the first occasion in the Jurassic Period there were open marine conditions from the Barents Shelf region directly south into the Tethys across the Russian Platform. Transgression in the Wandel Sea basin did not commence until Oxfordian time, and on Andoya not until Early Kimmeridgian time. Deep and quiet water conditions at sea often gave rise to poorly oxygenated sediments with limited or little biological activity. Kimmeridgian ash deposits on Andoya suggest

igneous extrusion from somewhere north of the North Sea. Basic intrusion started on Kong Karls Land also commenced during the Kimmeridgian Stage.

Tithonian (Volgian)-Boreal Berriasian (Fig. 19.16d).

Organic-rich shales characterize the Early Volgian strata, especially in the east of the Barents Shelf, perhaps indicating a local maximum of the Late Jurassic marine transgression. Regression started in the Barents Shelf in about mid-Volgian time, when there were often minor stratigraphic breaks in sequences as in Early Tithonian strata (Late Kimmeridgian) in southwest Spitsbergen. Sediments were characterized by abundant benthonic activity. By Late Volgian time, access to Tethys across the Russian Platform was closed south of the Volga region, but was reopened by middle Berriasian time. There was active intrusion of basic dykes in Svalbard. Uplift on Franz Josef Land gave rise to arenaceous sediments. There was a Tithonian-Berriasian unconformity and erosion in Kongsoya and eastern Spitsbergen.

Valanginian-Hauterivian (Fig. 19.16e). The broad regression which began before the Jurassic-Cretaceous boundary continued. Open marine conditions continued during Valanginian time on Svalbard. During the Hauterivian Stage Franz Josef Land became an emergent basic volcanic eruptive centre. In Kong Karls Land a Late Hauterivian hiatus is evident in an angular unconformity. A further cycle boundary was noted at the initial Valanginian boundary (Smelror 1994). Barremian (Fig. 19.16f).

Deposition of the marine Janusfjellet Subgroup in Svalbard and its equivalents across the Barents Shelf was followed by regression, as indicated by the appearance of continental facies in Barremian time. Fluvial-dominated sandstones, with marginal marine and deltaic sequences appear on the southeast coast of Spitsbergen. Fluvial facies drain east from the Palaeo-Hornsund High. There was marked subsidence in the Hammerfest Basin. Basic volcanism continued on Franz Josef Land and was also present on Kong Karls Land.

Aptian-Albian (Fig. 19.16g).

The eustatic mid-Cretaceous transgression commenced over much of the land exposed in Barremian time. However, the Pechora Basin acted positively, causing local regression and constricting, but not closing access to Tethys. In Spitsbergen, the Palaeo-Hornsund High became less positive and uplift is only recognized in the northeast from which sediments were supplied to a deltaic system and sandy shelf. On Andoya (Norway), turbidity currents carried sediments into deep water and olistostromes formed derived from fault scarps. Basic volcanism cont i n u e d on Franz Josef Land.

Late Cretaceous (Fig. 19.18h). Globally high sea-levels prevailed during this interval. On the Barents Shelf, in the offshore basins, marine conditions continued without major break from Albian into Cenomanian time. The South Barents Basin, the Bjornoya-Ol'ginskiy Basin and the Pre-Novaya Zemlya Trough were probably major marine basins. The surrounding areas were positive and only on Franz Josef Land are Late Cretaceous sediments, transgressive sandstones followed by clays, recorded in situ. The absence of strata representing other Late Cretaceous stages, apart from Turonian and Campanian/Santonian sedimentary erratic blocks on Novaya Zemlya, and claystones in the Hammerfest Basin, suggests that the main uplift was Coniacian or Maastrichtian/Early Paleocene. Svalbard became tilted up to the north. In North Greenland, there was more coarse clastic deposition throughout the period than on the Barents Shelf, resulting in thick elastic sequence in central areas

JURASSIC AND CRETACEOUS HISTORY and volcanics in the northwest. Marine greywackes accumulated to the southeast. The Wandel Sea Basin deposits are all fairly local, and were formed in pull-apart basins in associations with dextral strike-slip faulting, local low-grade metamorphism and some northerly directed thrusting (Birkelund & H~tkansson 1983). In easternmost North Greenland, Kronprins Christian Land (KCL), following Late Jurassic and Early Cretaceous deposition under stable conditions further (Turonian-Coniacian)

387

sedimentation, developed in a dextral pull-apart basin in the Wandel Sea Hav strike-slip mobile belt. This was followed by localized dextral transpression, in probably late Cretaceous time, with en 6chelon doming and thrusting. This (KCL) matches but preceded the Spitsbergen (Eocene) transpressional Orogeny. The movements were taken up in the Spitsbergen Fracture Zone. (H~kensson et al. 1993; Pedersen, abstract in TSG meeting of Geological Society 5-6 March 1997).

Chapter 20 Paleogene history W. B R I A N H A R L A N D 20.1 20.2

with a c o n t r i b u t i o n with A N T H O N Y

Early work, 388 Structural and stratigraphic flame, 390

20.2.1 Structural frame, 390 20.2.2 Stratigraphic units, 390

20.5.4 20.5.5 20.5.6 20.5.7

CHALLINOR

& P A U L A. D O U B L E D A Y

Calypsostranda sequence, 397 Offshore Paleogene sedimentation, 397 Thermal degradation of organic matter, 398 Sedimentation and erosion in a strike-slip regime, 399 Paleogene structures (W.B.H., A.C. & P.A.D.), 399 Western basement zone, including Prins Karls Forland, 399 Fold and thrust belt, 400 West Spitsbergen Paleogene graben, 402 Structures of the Eastern Platform and Central Basin, 409 Paleogene structures in north and northwestern Spitsbergen, 410 Offshore northwest Spitsbergen, 410

20.3

Paleogene time scale and correlation, 391

20.6

20.3.1 20.3.2 20.3.3 20.3.4 20.3.5 20.3.6 20.3.7

International Paleogene standard, 391 Palaeobotanical age estimates, 391 Faunal age estimates, 392 Palynological age estimates, 392 Magnetic anomaly age estimates, 393 Isotopic age evidence, 393 Summary of conclusions on age of Svalbard Tertiary strata, 393

20.6.1 20.6.2 20.6.3 20.6.4 20.6.5 20.6.6 Structural sequence, 410 20.7

20.4

Paleogene biotas of Svalbard, 393

20.8

20.4.1 Continental environments, 393 20.4.2 Marine environments, 394 20.5

Paleogene sedimentation and tectonics, 394

20.5.1 Central Basin, 394 20.5.2 Kings Bay Coalfield, 395 20.5.3 Forlandsundet Graben, 396

The Paleogene chapter of Svalbard history is a quite distinct one. It begins with an unconformity, albeit a sub-parallel one representing a late Cretaceous hiatus. Resting on Albian and older strata, the Van Mijenfjorden Group of six formations totals a thickness of about 2500 m in the Central Basin of Spitsbergen. The outcrop is ringed by Early Cretaceous strata in a broad syncline (Fig. 20.1). The strata are largely non-marine, coal-bearing sandstones, with interbedded marine shales and they range in age through Paleocene and Eocene. From latest Paleocene through Eocene time the West Spitsbergen Orogeny caused (Spitsbergian) deformation along the western border of the Central Basin, but it is most conspicuous in the folding and thrusting of Carboniferous through Early Cretaceous rocks. The orogen extended westwards to and beyond the western coast of central and southern Spitsbergen including Precambrian and Early Paleozoic rocks, which had already been involved in earlier tectogenesis. The eastward-verging thrusting extended beneath the Tertiary basin and reactivated older faults to the east. In the wider context Svalbard, adjacent to the north coast of Greenland, had been an integral part of Pangea from Carboniferous through Cretaceous time. The northward extension of the Atlantic opening reached and initiated the spreading of the Arctic Eurasia Basin at the beginning of the Paleogene Period. This led to the separation of Svalbard together with the Barents Shelf and northern Europe from Greenland by dextral strike-slip transform faulting. In the course of this progression, oblique collision between northeast Greenland and Svalbard caused the mid-Paleogene Spitsbergian transpression. Subsequent strike-slip was transtensional with Svalbard bordering the Norwegian-Greenland Sea, in Neogene through Holocene time. Separate from the Central Basin are four further Paleogene outcrops. (1) The Ny-Alesund coalfield south of Kongsfjorden appears as a northern extension of the Central Basin but separated from it by the fold belt of the West Spitsbergen Orogen (which swings round in a northwesterly direction). The orogenic front overthrusts the coalfield from the south. (2) The Forlandsundet Graben strikes NNW-SSE within the western Basement High of the Orogen. Some Paleogene strata therein dip steeply, a result of the orogenic compression. The graben opened again receiving late orogenic strata affected by normal faulting into the graben. A complex transtensile, transpressive, transtensile sequence is recorded.

20.9 20.9.1 20.9.2 20.9.3 20.9.4 20.9.5

Regional tectonic sequence, 413 Paleogene tectouosedimentary history, 413

Pre-Firkanten Formation events, 413 Mid-Paleocene events (63-57 Ma), 415 Latest Paleocene-Eocene events (58-38 Ma), 415 ?Late Eocene-Oligocene events (c. 35-23 Ma), 417 Plate-tectonic sequence, 417

(3) Renardodden with Calypsobyen, south of Bellsund, is a fragment of coal-bearing strata downfaulted against older rocks. (4) The Oyrlandet outcrop in southernmost Sorkapp Land is poorly exposed. It may be an outlier of the Central Basin outcrop. Seismic profiles offshore suggest that there are similar sedimentfilled graben in approximate continuity with these basins (Eiken & Austergard 1987). The Paleogene strata were dominantly continental deltaic with occasional marine incursions. Coal measures are typical, and within the lowest formation have been exploited at six mining settlements: Longyearbyen, Barentsburg, Sveagruva, Grumantbyen, Ny-Alesund and Calypsobyen. The last three were finally abandoned in 1961, 1963, and 1919 respectively. The only direct evidence of Paleogene volcanic activity is in minor tuff input low in the Central Basin. Submarine volcanicity, especially of the Yermak Plateau offshore of northern Spitsbergen may be Paleogene. Palaeolatitudes have been consistently polar.

20.1

Early work

Nathorst reported (1910, pp. 374 et seq) that Tertiary plant fossils were found during Torell's 1858 expedition at Kolfjellet, north of Van Mijenfjorden by A. E. Nordenski61d and in 1861, similarly by Blomstrand south of Kongsfjorden and east of Gronfjorden. This material was described by Heer in his early publications (1866, 1868). In 1868, Nordenski61d recorded a rich Taxodium bed between Heerodden, Gronfjorden and Festningen (Festung). Heer recorded not less than 93 plant and 23 insect taxa from this locality (1870) which Nordenski61d revisted in 1872 and 1873, as also Kongsfjorden. From these discoveries Nordenski61d extended knowledge of Tertiary outcrops through the mountains on the south side of Isfjorden, Colesbukta to Adventfjorden. Marine molluscs were also found in the Tertiary strata, at that time. During Nathorst's 1898 expedition further discoveries were made in Storfjorden and from outcrops at Van Mijenfjorden through to Van Keulenfjorden by A. Hamberg, J. G. Andersson and G. Andersson. Moreover, in De Geer's 1908 expedition new fossiliferous horizons were found by B. Hogbom & Wiman. From these and other visits, and by the time Nathorst made his synthesis in 1910, from which the above account is abstracted, the

PALEOGENE HISTORY /12~

/9 ~

-81 o

/15~

/18 ~

SVALBARD PALEOGENE OUTCROPS

Q ,

I

,'l

I

.~ ."

., 9

.

"-~t

9

o

9

" rs

t'

'

/ ~.

i Ny-Alesund "

d

/ ~

"

Central Basin.

78 ~

Calypsobyen

_~_ Central

post Paleogene

Basin

7 ~ Paleogene folding ~

rylandet

Paleogene

'12 ~ I!i1Pre-Paleogene

,0

I

I

km

74030 '

I

100 19~

76 ~ [ * ~ . ' ~ : t Ill LV~r-~1

77~

/15 ~

/18 ~

Fig. 20.1. Map of Svalbard showing the distribution of Paleogene deposits, with areas of Paleogene deformation hatched.

389

Central Tertiary basin had been explored and delineated as had the smaller outcrops at Ny-Alesund, the Forlandsundet Graben and Calypsobyen. De Geer (1920) summarized the coal regions of central Spitsbergen. A critical study by Ravn (1922) of marine molluscs established a Paleogene, probably a Paleocene age for the Tertiary strata which had hitherto been assigned either to Eocene or Miocene epochs on the basis of the plant fossils. H~igg (1924, 1925) made a further study of marine faunas. With the implementation of the Spitsbergen Treaty in 1925, the systematic survey of coal resources of Svalbard began. The principal outcrops were Tertiary (Hoel 1924; Horn 1928, 1929a, b; Orvin 1934). General accounts of Svalbard placing the Tertiary deposits in their regional geological setting had, of course, been initiated with Nordenki61d & Nathorst (1910), followed by Frebold (1935) and Orvin (1940). From these studies it became increasingly clear that, at least some of the Tertiary strata were deformed along with the underlying Mesozoic strata in Tertiary time. This was especially well documented by Orvin (1934, 1940). By that time the succession in the main basin had been established in successive schemes all of which tended to follow the six-fold division of strata by Nathorst (Orvin 1940) totalling about 2000m. (Fig. 20.2). Since 1945, with the broad outlines of Tertiary stratigraphy established, attention has been paid increasingly to the detailed studies of palaeontology, sedimentology, and especially in relation to palaeogeology and tectonics. Biostratigraphic work was advanced by Manum (1962), Vonderbank (1970) and Manum & Throndsen (1986) (see Section 20.3 below). Research was facilated by the further definition of lithostratigraphic units following the same six divisions (CB 1 to CB6 here) set out by Nathorst as by Atkinson (1963), Major & Nagy (1964, 1972) Harland (1969), Major & Nagy (1972) and Steel et al. (1979, 1981) (Fig. 20.2). The six-fold scheme was modified according to sedimentological interpretation by Vonderbank (1970) and Livshits (1967-1974), each with quite new nomenclatures. However, these have not taken hold except in one respect, in what was perhaps the definitive description of the Central Basin (Steel et al. 1981). While engaging in sedimentological interpretation, they reverted to the six-fold nomenclature of Major & Nagy (1964) (CB1-CB6) and, with the exception that the CB3 and CB4, are redefined using two new names taken from the Livshits scheme of 1975. This elaboration of nomenclature stems directly from differences between the two areas where Major (in the centre and east) and Livshits (in the west) were describing the interfingering successions. During late CB3 and CB4 time, a radical change in sedimentation took place from a relatively stable environment, with continental source of sediment from the east, to one of marine incursions from the south. The new pattern reflected a new uplifting source in the west, namely the rise of the West Spitsbergen Orogen. Interdigitation of coarse sediments from the west led to marked diachronous boundaries between formations. Indeed, the later sedimentary pattern continued to reflect uplift in the west as the advancing delta and depocentre moved eastwards. These studies were part of a comprehensive investigation of the whole Central Basin. The sedimentary disturbances reflect the West Spitsbergen Orogeny whose resulting structures constitute perhaps the most visible manifestation of tectonism in Spitsbergen. The folding was already well known before Orvin wrote his (1940) outline; but the extent and complexity of the fold and thrust belt was perhaps not appreciated until Challinor's survey, from north to south between 1960 and 1969, as part of the Cambridge Svalbard Exploration project. This resulted in a series of cross-sections from Kongsfjorden to Sorkapp. However, they were unfortunately not published in his life time. They are, however, summarised in the series of simplified cross sections below (see Fig. 20.8b). This knowledge, together with investigations of the western belt of older rocks led to the definition of the composite West Spitsbergen

390

CHAPTER 20

Nathorst 1910 (>1200 m)

1. Oberste Sandsteinreihe (Mit Kohlen und Pflanzen) >313 2. Plattschriefdge Sandsteinreihe (Mit marinen Muscheln) >193 3. Obere schwarze Schieferreihe (Mit Fenersteinger6llen des Permokarbon) >230 4. Gr0ne Sandsteinreihe (Mit Wurmf;~hrten) 200 5. Unterer dunkle Schiefereihe 75 6. Unterste helle Sandsteinreihe (Zuunterst Kohlenfl6tze und Pflanzen, dar~ber marinen Muscheln) 150

Owin 1940 Hadand 1961 Atkinson 1963

Major 1964, 1972 Major & Nagy 1972 Hadand 1969

Vonderbank 1963-64,1970

Livshits 1964,1965

c

Upper plant-bearing sandstone sedes 500-600 m

Aspelintoppen Fm

Flaggy sandstone series -200 m

Battfjellet Fm

Nordenskioldt]ellet

8

Storvola Fm

AI

Upper Collinderdalen Fm _ _ Lower

Gilsonryggen Fm

Green sandstone series 200-250 m Lower dark shale series (marine and tufts) 20-130 m

8

Sarkofagen Fm Grumantdahl

o

Basilika Fm

Lower light sandstone series Firkanten Fm 110-120 m

Hollenderdalen FmUpper Lower Grumantbyen Fm Colesbukta Fm

Battl]ellet Fm

CB5

cr

Grumantbyen Fm

Basilika Fm

Basilika Fm

~. Barenlsburg Fm

CB6

Grumantbyen Fm

8 8

Adventl]ord

Aspelintoppen Fm

IBjomson~ellet Mbr Gilsonryggen Fm ~ / Frysjaodden HollendardalenFm Fm ~ b _ r

Frysjaodden Fm c~

Aspelintoppen Fm Delta plain, largely regressive sequence - response to WSO

This work

Battt]ellet~

Fordal Upper black shale series 300 m

SKS 1995 Adopted here

Steel et al. 1981

Firkanten Fm

vi

)

Endalen Mbr Todalen Mbr (delta plain)

Fm Firkanten

EndalenMbr Kolthoffberget Mbr Todalen Mbr Gren~orden Mbr

ca4

CB3

CB2

CB1

Fig. 20.2. Sequence of classification of Paleogene deposits in the Central Basin. Orogen (Harland & Horsfield 1974). Barbaroux (1966) followed Challinor. Subsequently a spate of structural papers has reported investigations on the fold and thrust belt, conveniently compiled by Dallmann et al. (1993). Many of the local details are abstracted in the regional chapters 4, 9 and 10. This deformation phase in Svalbard's history was identified, first as post-Van Mijenfjorden Group (e.g. Harland 1961) and then (coeval with the later sedimentation) as a transpressive event during the strike slip progression of Svalbard away from Greenland (e.g. Harland 1969; Steel et al. 1981). This led to the correlation of the tectonism on Svalbard with the ocean-spreading magnetic anomaly data (e.g. Pitman Talwani 1972; Harland 1975b) and further magnetic constraint on the evolution of the NorwegianGreeland Sea (e.g. Srivastava & Tapscott 1986). The above events were accompanied by the formation of the Forlandsundet Graben, the Renardodden and the Oyrlandet basins. The latter two may be half grabens, but Forlandsundet preserves a N-S graben with Tertiary strata on both sides. This was known since the early Prince of Monaco Surveys by Bruce and others (especially in 1906 and 1907), but only since 1960 was research focused on it, beginning with Atkinson (1962-63). It was fitted into the tectonic sequence (e.g. Harland 1961) and systematically investigated as recorded for example by Helland-Hansen (1990) and Gabrielsen et al. (1992). To visualize the whole Paleogene episode in its historical Svalbard perspective the general accounts of Worsley (in Aga et al. 1986) and Hjelle (1993) should be consulted, not least for their excellent photographic record. The confusion over nomenclature arising from this complex international history was resolved in 1995 by the Svalbard Committee of Stratigraphy, whose recommendations are adopted here (SKS, Dallmann et al. 1995).

20.2 20.2.1

Structural and stratigraphic frame Structural frame

The map of Spitsbergen (Fig. 20.3) based on Harland 1961, and modified after Dallmann et al. (1993, Fig. 2) and Flood et al. (3G, 1971) shows the distribution of Paleogene outcrops. Superimposed in dashed lines are the fault boundaries to geological terranes, named as used in this chapter. The Central Basin is defined, not only by the Paleogene outcrops, but at least by the more extensive Cretaceous outcrops which appear only latterly to have lost their Paleogene capping. It is clearly bounded on the west by the West Spitsbergen Orogen, the eastern zone of which is the conspicuous (eastern) fold and thrust belt exposing Carboniferous through Cretaceous strata. The eastern margin of this is the thrust front which marks the western limb of

the Paleogene syncline of the Central Basin. The western part of the orogen comprises the Basement High which nevertheless reflects within it significant folding and thrusting. It also contains the Forlandsundet Graben and half graben of Renardodden and of Oyrlandet if this is not an extension of the Central Basin, and to the west a Coastal Basement in the north. In southern Spitsbergen a further (western) fold belt appears to continue offshore to the NNE. In the north of the orogen, at its margin, is the overthrust Paleogene Ny-,~lesund Basin which was probably a northern extension of the Central Basin later separated by the Oscar II Land eastwards virgation. North of the Orogen and the Central Basin is the Northern Platform of Paleozoic and Precambrian rocks traversed by a system of N-S faults, originating much earlier, but reactivated as follows. The Raudfjorden and Breiboggen faults show slight deflecting offsets, each of 1 or 2 km, which are sympathetic with the Oscar II Land virgation. The major Billefjorden Fault Zone, active off and on since at least Silurian time, was extensively reactivated by Paleogene thrusting, as was the southern part of the Lomfjorden Fault Zone. East of the Lomfjorden Fault Zone is the Eastern Platform, an area which yields little of Paleogene history. To the east of its southern extension, however, in Storfjorden Mann & Townsend (1989) depicted a Storfjorden Fault Zone with reverse faulting, suggesting an incipient compressive 'flower structure'.

20.2.2

Stratigraphic units

A summary of the units accepted (as definitive for the purpose of this work) following the recommendations of the Committee on the Stratigraphy of Svalbard (SKS) follows. The problems of correlation will be left till later, so that this account simply consists of a tabulation of the local rock units in the different areas from top to bottom. The units follow outline descriptions of Paleogene strata in the respective regional chapters: 4 The Central Basin; 9 Oscar II Land and Prins Karls Forland; and 10, southwestern Spitsbergen. The units below are compiled accordingly. Central Basin Van Mijenfjorden Gp Aspelintoppen Fm, >1000m (CB6) Battfjellet Fm, 60-300 m (CB5) Frysjaodden Fm, 200-450m (CB4) Bjornsonfjellet Mbr Gilsonryggen Mbr Hollendardalen Fm Marstranderbreen Mbr (of Frysjaodden Formation) Grumantbyen Fm, 45-200 m (CB3) Basilika Fm, 10-350 m (CB2) Firkanten Fro, 100-170m (CB1)

PALEOGENE HISTORY

391

Bayelva Mbr, > 160 m (with Leirhaugen Beds at base 5-20 m) Leirhaugen Mbr, 5-20 m Kongsfjorden Fm Tvillingvatnet Mbr, 15-70m (with Morebekhen conglomerate at base. Kolhaugen Mbr, 0-40. Forlandsundet Graben Buchananisen Gp Balanuspynten Fm Sarsbukta Mbr, >600m Sarstangen Mbr, 1050m Aberdeenflya Fm, >2800m McVitiepynten Subgroup* Marchaislaguna Fm, 600 m* Krokodillen Fm, >400 m* Reinhardpynten Fm, >210 m* Sesshogda Fm, 120m* Selvgtgen Fm, Kapp Lyell region south of Bellsund Calypsostranda Gp Ranardodden Fm, >217m Skilvika Fm, 115.5m Rochesterpynten Fm, c. 50 m Oydandet Basin Tavlefjellet Suite.

20.3 20.3.1

Paleogene time scale and correlation International Paleogene standard

The stage names (Fig. 20.4) have a long history, based on successions mostly from western European epeiric seas, in which correlation depended largely on molluscan faunas. Being typically provincial, they were not particularly effective. It is only in recent decades that marine foraminifers, nanoplankton and radiolarians have enabled a relatively precise zonation for international application via ocean basin stratigraphy. The old names are thus standardized in a new way. For example the Danian, of chalk facies in the cliffs of Stevns Klint (Denmark), was regarded as latest Cretaceous until they were shown to be coeval with the Paleocene European Montian Stage and also with the American traditionally Tertiary Midway fauna. Thus, rocks of Danian age since about 1960 have been defined as Early Paleocene. Late Paleocene in Denmark is commonly referred to as Selandian which most, but not all, authorities would equate with the Thanetian standard. It is therefore relevant to consider the date when published correlations were attempted. Moreover, there are still adjustments to be made. But until GSSP for stage boundaries have been agreed for consistency, throughout this volume the chronostratic scale will be that of Harland et al. (1990). According to later Paleogene global standard the traditional stages are identified by foramineral zones P1 to P22 (Paleogene), nannofossils NP1 to NP25 (both older to younger) and radiolarian zones 12 to 25 (young to older) as tabulated in Harland et al. (1990). Fig. 20.3. Generalized Paleogene structural framework of Spitsbergen RFF, Raudfjorden Fault Zone; BBF, Breibogen Fault; BFZ, Billefjorden Fault Zone; LFZ, Lomfjorden Fault Zone. Opinions differ as to the southern trace of the BFZ, it is drawn here in a more westerly projections as based on Mann & Townsend (1989). Endalen Mbr Kolthoffberget Mbr Todalen Mbr Gronfjorden Mbr (and in southwest Oyrlandet Fm). Kings Bay Coalfield Van Mijenfjorden Gp Ny-Alesund Subgp Broggerbreen Fm

20.3.2

Palaeobotanical age estimates

It took some time to establish that the plant-bearing strata were Paleogene and not Miocene. The difficulty applied to all North Atlantic Arctic apparently coeval floras as in Northern Canada, Greenland, and the British Isles. That such widely differing interpretations persisted so long, may be attributed to the tendency amongst palaeobotonists to name fossils according to familiar living forms, without scrutinizing possible differences in a slowly evolving biota. The matter was resolved - against Miocene of Heer (e.g. 1870), Nathorst (1910) and Simpson (1961) and for 'Eocene' of Gardiner (1887), but not by plant fossils (Harland 1963; Livshits 1974; reviewed by Harland 1975a).

392

CHAPTER 20

"13 O

~ Q_

Epoch

Stage

Ng

Miocene

Aquitanian (Aqt) Oli,

Chattian (Cht)

6_~ N4

NN1

P22

NP25

Oli 2

Rupelian (Rup)

P21

a~

UJ Z LU

Bartonian (Brt)

(D 0

P16 P15 P14

NP21 ~

1.

35--

- 3 5 . 4 - -

NP19

~ NP17

7 8 9 10 11 12

NP22

38.6 -

17

P13 NP16

18

/~i nu

- -

13 15 16 17 18 19

-42.1 -

P12

Eoc 2

Eocene

Lutetian (Lut)

Pll

P9

Pal2

P7

Thanetian (Tha)

Paleocene

I=mr-,~ Gulf (Gul)

-

19

45

P1

NP12

P5 P4

NP9 IMI~K N~K NPg

~dad

21 22 23

20 21

50.0

50

25 --

N~-,~, NP1

Maastrichtian (Maa)

Faunal age estimates

The first study of marine molluscs by Ravn (1922) was based on material collected from the Central Basin south of Isfjorden (mainly Colesbukta). The fossils had been collected by earlier Swedish and later Norwegian expeditions. Of the 18 taxa identified, most were from the lowest series (CB 1), others were from CB3 and CB5, and some of uncertain provenance. New species were of course useless for correlation and of six taxa known from the Anglo-Belgian-Paris Basin, Mid- and Late Paleocene and Early, Middle and Late Eocene ages were indicated. Although with so little material the conclusions were somewhat indeterminate, the work established that the Tertiary Central Basin was Paleocene and/or Eocene and not Miocene. Rosenkrantz (1942) compared Tertiary biotas of West Greenland with the type Danian of Denmark and found them to be coeval. One fossil crustacean was common also to Spitsbergen, so a Danian age was suggested. Thereafter biostratigraphic investigations were altogether more systematic in which the investigators worked on material they had collected. Vonderbank (1970) made a thorough study of all previously available faunas along with new collections from Isfjorden and Van Mijenfjorden. Horizons were based on his new stratigraphic descriptions. The 72 foraminiferal taxa were described or discussed of which half are also Holocene and typically from polar environments. The conclusion of this, as yet the most thorough faunal investigation, was that a mid-Paleocene age, i.e. Late Danian to Early Thanetian fitted the data best. Livshits and Russian co-workers also investigated the Tertiary strata of Spitsbergen from 1965 onwards and made careful palaeontological and petrographical observations in their lithostratigraphic descriptions. A concluding work (1974) gave ages (which were repeated in 1992) for CB1 and 2 as Paleocene, CB3, 4 and 5 as Eocene and CB6 as Oligocene. The ages of strata in the other basins were also fitted into this scheme (summarized in 1992),

55

24

-56.525

--~z - ~ NP3

22 23

24

NP11 NPIO

P2

Danian (Dan)

NP13

P6

P3

Pal,

NP14

P8

Ypresian (Ypr)

Eoc.

NP15

2O P10

20.3.3

29.3 _ 30 - -

NP23

P19

P17

Priabonian (Prb)

6 2 5 - -

NP24

P18 Eoc3

-23.3--

P20

Oligocene

CHRONOMETRIC AGE Estimated Linear Magnetic boundary scale anomaly calibration (Ma) Ma)

BIOZONES

CHRONOSTRATIC AGE

-60.5---

60

Not found

26 27 28

65.0 ~- 65

29 3O

Fig. 20.4. Paleogene time scale (after Harland et al. 1990, with permission of Cambridge University Press).

thus post-CB6 (i.e. later Oligocene) would be the Sarsbukta Member of Forlandsundet. Equivalent to CB6 would be the strata at Renardodden and at Marchaislaguna in Forlandsundet. The earlier Forlandsundet strata would be equivalent to CB4 and 5 with a possible Oyrlandet age of CB1. However, thorough though the work may have been, the correlations were made with Russian Tertiary strata whose ages were assumed to be authentic without serious attempts at international correlation. In these circumstances the correlations within Svalbard may have some value but the international ages of the Russian strata is traditional. Feyling-Hansen & Ulleberg (1984), from foraminiferal investigation of the Sarsbukta Member also concluded an Oligocene age.

20.3.4

Palynological age estimates

Manum and co-works (e.g. 1960; Manure & Throndsen 1986) have engaged in a continuing quest to read the plant record. From a careful study of both macro- and microflora Manum (1962), in commenting on the difficulties of such correlations (e.g. of 70 pollen and spore types), concluded that 'According to paleozoological dating the age of the beds is Late Paleocene to Eocene. No means for a more precise age determination has resulted from the present investigation, but the results are consistent with the previous dating'. More than twenty years later (Manum & Throndsen 1986), from new evidence of dinoflagellates suggested that CB2 would approximate the Early-Late Paleocene boundary; CB4 would be latest Paleocene (approximating to the initial opening of the Norwegian Sea at Anomaly 24-25). A late Eocene age had already been suggested for the Sarsbukta Member of the Forlandsundet Graben (Manum 1960) and was confirmed in 1962 by Manum & Throndsen (1986) as Late Eocene. This contradicted the conclusion of Feyling-Hansen & Ulleberg (1984) of an Oligocene age. It is not clear to what extent they were attempting to date the same rocks. Head (1984) also working on dinoflagelates suggested a Late Eocene-Early Oligocene age for the Renardodden strata.

PALEOGENE HISTORY 20.3.5

Magnetic anomaly age estimates

Magnetic anomalies are correlated by the distinctive signatures of ocean stripes which are in turn dated independently by marine micropaleontology and so correlate with the standard scale (Fig. 20.4). The sequence o f events taking Spitsbergen from its Pangea position north of Greenland to its present location will be discussed in Section 20.8 and Chapter 21. However, anticipating the opinion, there argued, that the West Spitsbergen Orogeny occurred in latest Paleocene and Early to mid-Eocene time, it is reasonable to seek a timing for that transpression by the relative motions of Greenland and Spitsbergen. Pitman & Talwani (1972) extrapolated from data based on the spreading of the north Atlantic well south of Spitsbergen and north Greenland latitudes and showed (1972, fig. 8) that the closest Spitsbergen came to North East Greenland was at about 47 Ma (approx. mid-Lutetian i.e. early Mid-Eocene). This indication of a possible overlap was noted as a probable correlation with the West Spitsbergen Orogeny (Harland 1973b). However, Le Pichon, Sibuet & Franchetau (1977) avoided the overlap by assuming 'a relatively large motion between Greenland and the Lomonosov Ridge during the early opening of the Eurasian basin (63-53 Ma according to Pitman & Talwani)' so transferring the problem to movements in the region of the Nares Strait. Srivastava & Tapscott (1986), with more Arctic magnetic data, pointed out that anomalies 21 and 23 allow a satisfactory fit treating the Lomonosov Ridge as part of the North American Plate. However, there is some freedom for manoeuvre at this time, and again the problem of overlap is transferred to a consideration of regional events as between the opening of the Eurasia Basin or, as they favoured, by developments off the Iberian Peninsula. Eldholm et al. (1988, 1990), focusing directly on the Svalbard Greenland relationships, and especially on the evolution of the Norwegian-Greenland Sea, showed anomaly 23 (their 55 Ma, our 52-53Ma) as a time of juxtaposition of Svalbard and eastern North Greenland. They argued that prior to anomaly 13 (36Ma), Svalbard slid along-side Greenland (transcurrence and possible transpression) and thereafter with transcurrence and ocean spreading. From the above it is clear that the West Spitsbergen Orogeny had ceased a compressive component by anomaly 13, i.e. at late Eocene time at the latest. The onset of the compressive component (transpression) could be around anomaly 23 or even 25. Thus, the

Age Neogene r

Heer Orvin 1940 (Harland 1961 Nathorst 1910 (Simpson 1961) Atkinson 1962) CB1-6

Livshits 1965-74, 1994

Chattian (Cht)

393

initial circumstances for a possible transpression would be from Late Paleocene (mid-Thanetian) and probably active in Ypresian (Early Eocene) time. These relationships could be used, and generally are used, conversely, to argue that the West Spitsbergen Orogen, dated from the sedimentation pattern of the Central Basin matched a particular anomaly. But the poor constraints of either approach may be commensurate. At least they are broadly consistent. 20.3.6

Isotopic age evidence

No direct determination of Svalbard's Paleogene rocks has yet been made, but indirectly, for example, the determination of the age of some Scottish granites (e.g.c. 60 Ma, Miller & Harland 1963) that arguably postdated the Mull plant beds is relevant, because at that time a Miocene age for all the North Atlantic plant beds (Scotland, Ireland, Greenland and Spitsbergen) was seriously considered (Simpsen 1961) and all seemed to have similar floras. At that time this determination was a positive indication of a Paleocene rather than a Miocene age. 20.3.7

Summary of conclusion on age of Svalbard Tertiary strata

Successive opinions as to the correlation of Tertiary strata in Svalbard are presented in Fig. 20.5, using the unit classification coded for this work (CB1 to CB6) for easy comparison. 20.4

Paleogene biotas of Svalbard

Enough has been said above to conclude that for various reasons Paleogene biotas are not well suited to chronostratigraphy. In part this arises from the affinity of the fossils to Holocene organisms. This in turn enables a better appreciation of the environments than is possible from earlier biotas. 20.4.1

Continental environments

Plant fossils. The palaeobotanical records of the earlier workers have been conveniently synthesized by Manum (1962) along with his own palynological studies. He tabulated all macrofloral records

Vonderbank 1970

Schweizer 1974

Head 1984 Manum & Throndsen 1986

SKS 1995 and adopted

here

FSG 3

8 o

Rupelian (Rup)

CB6

Bartonian (Brt)

Calypso

FSG 2 and Ny-A

Priabonian (Prb) Forlandsundet Graben (FSG)

Lutetian (Lut)

Calypso FSG 4

FSG 4 ? 9

CB5 FSG 1

FSG 3

I I

CB6

CB4

FSG 2

Orogeny CB3 { ab

Ypresian (Ypr)

Thanetian (Tha) (Selandian) Danian (Dan)

L CB6 CB5 CB4 CB3 CB2 ~r CB1

CB5 /-CB6 J/-CB5

CB2 CB1

CB1-6 CB4 CB2

T~--CB2 "--CB1

Cretaceous

Fig. 20.5. Successive interpretations of the age of Paleogene strata and events in Svalbard.

CB4 { b CB3 a CB2 CB1

V

I Ny-A I FSG 1

394

CHAPTER 20

with references according to a modern classification and listed related palynomorphs and their stratigraphic horizons alongside. Below are listed the major and minor taxonomic headings extracted from his 10 pages of systematic information supported by discussion of synonymies. (sp and p = no of macro plant and no of palynomorph species respectively) Bryophyta (1 sp § 1 p). Pteridophyta Lycopodiinae (2 p) Equisetinae (3 sp) Felicinae Osmundaceae ( p + 2 p) Schizaeaceae (?1 p) Dennstaedtiaceae (? sp) Polypodicaceae (?2 sp + 4 p) Incertae sedis (1 sp + 2 p) Bryophyta or Pteridophyta (4 p) Gymnospermae Ginkgoinae Ginkgoaceae (3 sp + 2 ?sp) Coniferae Pinaceae (~13 sp + l?sp + 9 p) Taxodiaceae (12 sp + 2 p) Cupressaceae (4sp) Incertaesedis (2 sp + lp) Angiospermae Gnetinae (1 ?sp) Dicotyledoneae Nymphaceae (2 sp) Cercidiphyllaceae (2 sp) Ranunculaceae (1 ?sp) Magnoliaceae (1 ?sp) Rosaceae (5 ?sp) Hamamelidaceae (3 sp) Platanaceae (1 sp + ?1 p) Papiloniaceae (1 ?sp) Elaeognaceae (1 ?sp) Droseraceae (1 p) Tiliaceae (4 sp) Aceraceae (3 sp + lp) Sapindaceae (1 sp) Celastraceae (1 sp) Rhamnaceae (2 sp) Vitaceae (1 sp) Nyssoceae (2 sp) Cornaceae (1 ?sp) Araliaceae (1 sp) Betulaceae (8 sp + 5 p + ? 3 p) Fagaceae (2 sp) Incert~sedis (5sp + 12p dicots + lp) Monocotyledonae Juglandaceae (2 sp + 2 p) Salicaceae (2 sp + 2? p) Najadaceae (1 sp) Liliaceae (1 sp) Iridaceae (25 p) Juncaceae (1 sp) Cyperaceae (3 sp) Graminae (2 sp) Araceae (1 sp) Sparganacea (1 sp + 2 p) Kvacek & M a n u m (1993), from a study of Paleogene ferns in Spitsbergen, and from comparisons in the Brito-Arctic igneous province, concluded a temperate flora of relatively low taxonomic diversity, as also reflected by the angiosperns. 'On Spitsbergen, Osmunda and Coniopteris are, together with Equisetum, associated with rich remains of Metasequoia and Zizyphoides flabellun. Swampy, oligotrophic conditions where Metasequoia played a dominant r o l e . . , were particularly suitable for the above mentioned association' (Kvacek & Manure 1993, p.177). Kvacek, Manum & Boulter (1994) also reported on Spitsbergen Paleogene angiosperms.

20.4.2

Marine environments

Vonderbank (1970) carried out the most comprehensive investigation of marine faunas hitherto. His stratigraphic scheme demonstrated rigour in collecting, but his stratal nomenclature, being highly interpretative, has not been followed. His principal contribution was the study of foraminifers of which he listed 62 forms from Isfjorden and Bellsund; 36 are known from recent occurrences in mainly polar environments. The other 36 were the basis of his age estimates. In addition to his foraminifers he listed occurrences of the following. Arthropoda Crustacea Decapoda Galathea Spitzbergica Group 1927 Gastropoda Apoiihaidae Chenopus gracilis Naticidae Ampullocnatica isfjordensis Seaplandiodae: Cylichna discerifera Bivalvia Nuculana (Jupitaria) hoeggin. sp. Yoldia sp. ?Arca sp. Modiolus hauniercis (Rosenkantz 1920) Mytilum plenicostatus Amassium Anodontia spitzbergensis n.sp. Conchoclele conad~"(Rosenkantz 1942) Solecurtus n. sp. S. Spitsbergensis (Rau Hagg) Corbiaae altissima Rau 22 C. angumdideus Rau Cyprina sp. Pitar (Callista) nathorsti Rapu Pitar pyriforum Pisces Pseudamia only one find Tracefossils Gyrophyllites kwassizensis Ophroinorpha nodosa Dinoflagellates (earlier refered to as hystricospheres).

20.5

P a l e o g e n e sedimentation and tectonics

Paleogene strata in Svalbard reflect the tectonic events of the West Spitsbergen Orogeny. The resulting structures belong to the following section (20.6). It is convenient here to treat first the main outcrop of the Central Basin plus the Ny-Alesund (and the Oyrlandet) strata, and then the graben within the western horst.

20.5.1

Central Basin

Central Basin is preferred to Central Tertiary Basin in that it refers to a wider terrane and with a longer history in which only the Paleogene story is relevant here. It tells of sedimentation at about sea level, with recorded subsidence of at least 2.5 km in the centre followed by another estimated 1 km. The Neogene story may not be basinal at all. Because later Cenozoic uplift and erosion exposed the basin strata, with summit heights now at around 1 km above sea level. The Paleogene succession is depicted in Fig. 4.3 in schematic form taken from Steel et al. (1981) and modified by SKS (1995). Their interpretation based on detailed sedimentology is followed here. For this purpose, the earlier work of Livshits (1965-1975) and Vonderbank (1970) has been taken into account by Steel et al. including aspects of fluvial, deltaic and coastal facies in terms of

PALEOGENE HISTORY transgressive and regressive sequences. A highly mobile picture of the evolving basin results in which the lithological units often interfinger, being wedge or lens shaped i.e. typically diachronous. Firkanten Formation (CB1) begins locally with a thin basal conglomerate, the Gronfjorden Member, which is followed by a shale-sandstone-coal sequence (Todalen Member 60 m) indicating a delta plain environment. The Todalen Member reflects deposition in the northeast in a fluvial-tide-dominated environment passing transitionally to the southwest to a more uniform 'lower plain succession'. This is followed by a quartz-arenite sequence (Endalen Member) interpreted as delta-front sheet sandstones in the northeast. In the southwest of the basin, the Endalen Member passes transitionally, and by interfingering, into the Kolthoffberget Member of fine-grained sediments interpreted as low delta front (i.e. prodelta) deposits. There is thus a progression from NE to SW: (top-set) deltaplain, through (fore-set) delta-front deposits, to (bottom-set) prodelta sedimentation. But although there appears to be a systematic transgression, the Firkanten Formation is made up of about ten individual regressive sequences. Steel et al. suggested that the delta plain consisted of several advanced lobes, possibly of a super delta, extending throughout the Eastern and Northern Platform and even encroaching thence intermittently into the Central Basin. Indeed, the tendency for Spitsbergen to continue upward tilting towards the north, evident in Late Cretaceous time, may have continued and so provided sediment sources in the north as well as in the north east. Basilika Formation (CB2). The tendency just mentioned may account for the CB2 thickness increasing from 20 m in the northeast to 300m in the south and southwest. There is a parallel change from thinner sand and silt in the northeast to thicker shale in the deeper water. The formation is dominantly shaly, so indicating an overall deepening of water in the basin. However, the same easterly to northerly source of sediments applies. Thus far subsidence kept pace with or exceeded deposition and Steel et al. referred to CB 1 & CB2 as the first or transgressive phase. The Grumantbyen Formation (CB3) foreshadowed the second (regressive) phase with basin infilling. Two units approximate to the original CB3 (Sarkofagen Formation), i.e. Grumantbyen and Hollenderdalen with their coarser facies, but the interdigitating configuration is not so simple. The glauconitic sandy bioturbated Grumantbyen Formation, 450 m is a massive unit. It is interpreted as forming in a shallow offshore bar complex. The present-thrust front of the West Spitsbergen Orogen appears to have truncated the Paleogene basin so that its original westward nature and extent can only be surmised. The coarser Grumantbyen Formation may be the forerunner of uplift in the west, but the Hollendardalen Formation is clear evidence of a new sediment source in the west. That it thins into shales eastwards, suggests an eastward deepening and movement eastwards of the basin axis. These events were probably latest Paleocene and so date (CB4a) the early stages of the West Spitsbergen Orogeny. The third phase (of Steel et al.) continued the regressive-basin infilling to the end of the stratigraphic record of the basin i.e. CB4, CB5 and CB6. It continued to be dominated by the continued uplift of the West Spitsbergen Orogen which then supplied sediment. Dalland (1977) noted the presence of erratic clasts in the upper part of the Sarkofagen Formation. The formation is currently the approximate equivalent of the Grumantbyen and Hollendardalen fms so these observations refer to the Grumantbyen Formation. He described (i) radomly flattened stones, (ii) concretions on (storm) erosion surfaces, and (iii) other concretions in thin horizons. Amongst various explanations for their origin,rafting by winter ice was favoured and analogous to Cretaceous dropstones (Pickton 1981). Birkenmajer & Narebski (1963) reported drifted blocks of dolerite in the Sorkapp Tertiary strata. The Hollendardalen Member (CB4a) interdigitates with the finer Frysjaodden Formation and thins from 150 m in the west to zero near the basin axis. It consists of tidal dominated deltaic sandstone wedges which thin and grade eastwards into shales. This represents a significant shift in sediment source indicating uplift in the west.

395

The Frysjaodden Formation (CB4b) now comprises the original Gilsonryggen Formation as well as the westward thickening wedge of the Bjornsonfjellet member (CB4b, c). The newly instituted Marstranderbreen Member is applied to that part of Gilsonryggen shaly facies that lies between the sandstone Grumantbyen and Hollendardalen Formations and so may be the last stage before sedimentation from the west. The Gilsonryggen Member is a uniform silty shale succession from 200 m in northern Nordenski61d Land to 400 m south of Van Mijenfjorden where it is named the Frysjodden Formation, and is not penetrated in the east by the coarser western wedges, especially of the Bjornsonfjeilet Member in the west. The western facies is associated with turbidite sequences, slump and other soft sediment deformation structure of western origin. The presumed deltaic facies, from which these derived, were west of the later thrust front. Scattered lonestones probably indicate ice-rafting. Lonestones, interpreted as pebbles floated to the Central Basin by driftwood or other floating vegetation from rivers have been noted in the middle formations of the Van Mijenfjorden Group (Nathorst 1910) specifically from members of the Frysjaodden Formation by Birkenmajer, Federowoski & Smulikowski (1972). Rhyolite porphyries, granites, dolerite, vein quartz, quartzitic sandstone and Permian cherts were among the 17 specimens collected. The acid igneous rocks were probably derived from the basement in Nordaustlandet and the rest need not have travelled so far. All are probably of northeasterly provenance and precede the time when the main sediment supply was from the west. The Battfjellet Formation (CB5), dated as Eocene (Manum & Throndsen 1978) is a 'prominent shoreline delta-front, sheet sandstone, varying in thickness from 60-200 m that developed over the entire Tertiary Basin. It forms the upper part of an upwardcoarsening megasequence' (Steel et al. 1981, p. 659). Thus the units CB4 and 5 belong together. There is evidence of infilling from north, east and west. Two deltaic distributary channels have been identified, but most sedimentation was wave generated. The Aspelintoppen Formation (CB6) 1000+m, comprises a somewhat mixed assortment of sandstone, siltstones, calcareous shales, clay ironstones and thin coals and is mainly a delta-plain formation. Soft sediment deformation is conspicuous throughout. This first alerted Cambridge geologists to the sedimentary impact of the orogen. The tectonic context of the basin development and its deformation in relation to the plate motions between Greenland and the Barents Shelf is discussed after the structures have been introduced (20.6). Seismic data indicate that Tertiary deposition ceased in midOligocene- a time of maximum burial (Steel & Worsley 1984). Post-Oligocene erosion of the Central Basin may total between 1.5 and 3 kin. Further speculation depends on assumptions about the thermal conductivity of the cover (Michelsen & Khorasani 1991). Michelsen and Khorasani also showed that Carboniferous coals at Trygghamna and Bellsund in the west had been more deeply buried than those in the Billefjorden area just north of the Central Basin. Steel (1992) expressed a similar sequence in terms of sequence stratigraphy.

20.5.2

Kings Bay Coalfield

The stratigraphy of the coal-bearing rocks at Ny-,&lesund was reported fully by Orvin (1934) who had access to sub-surface data at that time. However, mining continued with interruptions till 1963, with extensive developments which are recounted in general (Hanoa 1993), but the geological report by Midboe in 1985 has not been published. However, some information from it is available through SKS (Dallmann et al. 1995). Taking this information into account and giving priority to Challinor's (1967) work, the succession (as in Chapter 9) is as follows from the top.

396

CHAPTER 20

Van Mijenfjorden Gp Ny-Alesund Subgp Broggerbreen Fm Bayelva Mbr Leirhaugen Mbr Kongsfjorden Fm Tvillingvatnet Mbr with basal Morebekken conglomerate Kolhaugen Mbr resting on Triassic and Permian strata. The schematic interpretation of the Tertiary strata as above shows that the two-fold division of Orvin needs reinterpretation because a conspicuous unconformity (from borehole information) separates the two members that are equivalent to his lower division. From this it is arguable that the major division is not so much at the boundary between the two formations as within the lower one at the unconformity above the Kolhaugen Member. From a tectonostratigraphic point of view the Bayelva and Tvillingvatnet members are internally concordant and separated from the Kolhaugen Member below, which is cut out completely in the north by the unconformity. According to the section provided by Midboe (SKS 1995) there was uplift to the north, and the basin thickens southwards to its maximum where its truncated by the later thrusting (Fig. 9.3). Already the uplift from S to N had thinned the Vardebukta Formation from 50 to 0 m. The Ester eoal seam at the base of the overlying Kolhaugen Member is parallel to that slight unconformity (less than 1~ But stronger uplift to the north and erosion truncated the Kolhaugen Member and a basal conglomerate to the Tvillingvatnet Member was clearly supplied from the north. The Ny-Alesund Subgroup has generally been correlated with the Firkanten Formation and probably the Basilika Formations of the Central Basin, i.e. early to mid-Paleocene. Indeed, the similarity of facies, and probably of age, suggest that it is an outlier of the Central Basin, separated tectonically by later orogenic virgation. Support for this view may be gained from the basal peneplane on which it rested. In southern Spitsbergen it rests on the top member of the Albian Carolinefjellet Formation and northwards through the central outcrop it successively oversteps lower members in that formation. Extrapolating NNW to Ny-Alesund it rests directly on the Vardebukta Formation and in the extreme north rests on Permian strata. The whole Mesozoic succession has been tilted up to the north and truncated, a loss of about 2500m of strata in 250km i.e. a gradient of 1 in 100 or 0.57~ The Vardebukta Formation beneath the Ny-Alesund Formation as already shown is wedge shaped by about 50 m in the south of the coalfield and about zero 5km to the north--an angle entirely consistent with the overall projection. This appears to rule out any significant tectonism in Late Cretaceous time, with the marked unconformity within the Ny-Alesund Formation and the wedges of conglomerates from the north indicating an increased rate of tilting possibly as the earliest premonition of the West Spitsbergen Orogeny in mid to late Paleocene time. This cannot apply generally because the Firkanten Formation in the Central Basin is fairly uniform throughout its outcrop.

20.5.3

Forlandsundet Graben

The sound between the mainland (Oscar II Land) and Prins Karls Forland exposes Paleogene strata on each side. The contacts on each side, with older rocks, mostly Vendian to Early Paleozoic, are generally faulted, but some are depositional. Thus, the structure appears as a sediment-filled fault-bounded, elongate basin (i.e. graben) with coarse sediments (often conglomerates with large boulders) deriving probably from fault scarps on the flanks and passing into finer sediments forming in a marine basin along the axis. This is the picture presented by Atkinson (1962, 1963). A graben is not necessarily defined as extensional as Kleinspehn & Teyssier (1992) suggested. The sedimentary sequence as shown in Chapter 9 and summarized above (20.2.2) reflects this picture with the northeastern outcrop of the Aberdeenflya Formation representing an earlier and/or later development of the basin deposits. The ages where determined appear to be Eocene, with the possibility that the earliest strata may be Paleocene; and the latest strata Oligocene. Seismic (and gravity) profiles indicate some 5 km of thickness of graben infiU beneath the sea (data from Rye-Larsen in SKS 1995).

M a n u m & Throndsen (1978a, b) argued from vitrinite reflectance measurements that a further 2 km of strata have been removed from above. Therefore the thickness must have totalled c. 7 km, presently in a graben only 15-20 km wide. Chapter 9 concluded with the following succession (from the top) Buchananisen Gp Balanuspynten Fm Sarstangen Mbr Sarsbukta Mbr Aberdeenflya Fm in the north may be equivalent to much of the following sequence McVitiepynten Subgp Marchaislaguna Fm Krokodillen Fm Reinhardpynten Fm Sesshogda Fm and below the subgroup is the Selv~gen Formation.

SelvAgen Formation. There is little question as to the origin of the Selvgtgen Formation in the west, where the coarse conglomerates are themselves involved in normal faults down to the east, and the source of which would appear to be the adjacent fault scarps. Atkinson (1962) described it as a conglomerate resting unconformably on pre-Devonian rocks with red-weathered clasts. It is against the Prins Karls Forland Horst. Boulders up to 1 m across occur in the basal conglomerate, some are rounded, others are rectilinear resulting from erosion of joint blocks with minimal transport. Within the conglomerate are slaty 'sole' components up to a metre thick. Higher in the formation, size of clasts decreases to sand grade and the slate is broken up. Even so very coarse beds of conglomerate recur at decreasing intervals. The source was clearly to the west as confirmed by imbrication in some boulder beds transported with highly variable energy. The thickness of each unit increases towards the source area, in the west more than doubling in a km to a maximum of c. 1000m (Livshits 1974). On the eastern side, the Sarsbukta Member is not so coarse and is better stratified, it appears to have a similar origin and was probably formed at a later date. The contacts appear all to be faulted.

McVitiepynten Subgroup.

Atkinson described this 2000 m unit (his McVitie formation 1962) as resulting from erratic and rapid alternations from conglomerate (20%) through dominant sandstones (50%) to siltstones (10%) and shale (18%), the alternations being the result of uplift and variations in local stream energy. The sandstones from their mixed mineral content were classified as (low rank) greywacke. Shales are black, carbonaceous material is c o m m o n with lenses and fragments of bright brittle coal. Soft sediment deformation is typical in finer facies with boundinaged sandstone, and rupture and folding of sandstone beds in shale interpreted as the result of slumping. Because no marked angular unconformities are evident in the Paleogene sequence it was taken by Atkinson (1962, p. 351) that sedimentation in the graben kept pace with uplift at the margin. While generally maintaining a sedimentary gradient. Livshits (1967, 1974) distinguished four formations overlying the SelvAgen Formation and equivalent to Atkinson's McVitie (pynten) formation as follows. The Sesshogda Formation (120 to 300 m) of alternating facies contains two species of bivalve, at least four plant forms, dinoflagellate species and pollen. The Reinhardpynten Formation (210 m) with grey and then black siltstones with bivalves. Krokodillen Formation (410m), follows conformably and of similarly mixed facies is the Marchaislaguna Formation disconformably above is a coarse unit with more conglomerates. It totals perhaps 2000 m. The Aberdeenflya Formation (Rye-Larsen in SKS 1995) is generally a finer grained deposit. It crops out in the northwest of

PALEOGENE HISTORY the graben in the northeast of the island and possibly comprises mostly submarine material. It may be a facies spanning a wide age range, including the earlier deposits affected by compressive (transpressive) events as well as by later extensional sedimentation. The Balanuspynten Formation is the SKS (1995) name for Atkinson's Sars Formation (1962) on the east of the graben. It is probably of later age and is a finer grained, somewhat similar analogue, of the SelvSgen Formation in the west. It comprises two members (agreed by SKS 1995). Sarstangen Member occupies the lower ground to the west and was penetrated by the borehole at the end of the spit of that name. It is in sheared contact with a m61ange of strike-slip elements of older rocks (Ohta et al. 1996). Sarsbukta Member occupies the cliffs and higher ground to the east and is dominantly of sandstones and siltstones with at least one thin coal seam. The stratal sequence suggested is supported by reflectance studies of the contained coal, in which the western (SelvSgen/ McVitiepynten) deposits required an overburden of 6-10km, whereas the Sarsbukta deposits required only about 2 km (Kleinspehn & Teyssier 1992, p. 96). These differences may not be purely depositional, but are probably related to the complex structural history of the graben. Moreover, soft-sediment deformation shows that tectonic movement was active during deposition. Gabrielsen et al. (1992) suggested a complex tectonic sequence controlling sedimentation as follows. An initial local dextral transtension, possibly in a regional transpressive region may have resulted in Early Eocene development of a basin somewhat wider than the present graben. Then during continued deformation the graben divided into at least four units with associated marginal segments from north to south (units A B, C and D and segments E1 to E4 and W1 to W4 of Gabrielsen et al. 1992) which behaved somewhat differently (Fig. 9.9). In each case the marginal alluvial fan sequences (e.g. Selvfigen and Balanuspynten fins) grade into near-shore shallow marine units of the McVitiepynten Subgroup while the northern and central parts of the basin are submarine fandominated as in the Aberdeenflya Formation. Gabrielsen et al. (1992) tentatively inferred four stages in the development of the graben; taking into account the structural analyses of Lepvrier (1990) and Kleinspehn & Teyssier 1992. (1) Initial general transtensional subsidence with dominant deposition from the west. (2) Local (?sinistral) shear broke up the complex graben into the afore mentioned segments. This folded some strata into cross folds and thrusts with northerly vergence (their type 1 structures). This was a time of local rapid subsidence within the separate pull-apart segments. (3) A compressive (transpressive) regime caused folding and thrusting with fold axes oriented parallel to the graben (their type 2 structures) with a narrowing of the basin. (4) An extensional (transtensional) regime followed with drag structures tending to parallel the late normal faulting which cut the compressional structures. The sedimentary evidence interpreted above reflects only the late or post-orogenic history of the graben. As already argued in section 9 an earlier history of transtension (with deposition of at least part of the northern Aberdeenflya Formation) was followed by strong transpression as argued by Lowell (1972) and by Steel et al. (1985). However, it seems unlikely that the transpressed graben contained all the later sediments as depicted by Steel et al. The sequence might then be: (1) initial dextral transcurrence (pure strike-slip): early Paleocene; (2) transtension with initial deposition in a pull-apart-basin: early to mid-Paleocene; (3) transpression - part of the West Spitsbergen orogenic climax: latest Paleocene through to mid-Eocene as seen by Lowell and in part by Steel et al. (1985); (4) transcurrence, to transtension with pull-apart sequence as described by Gabrielsen et al. (1992); (5) minor transpression; (6) transcurrence, late Oligocene and ?later.

20.5.4

397

Calypsostranda sequence

At Renardodden is a Paleogene (Calypsostranda Group) downfaulted against Vendian strata of the Kapp Lyell Group. It is bounded by sea to the north so that its structural setting is uncertain. It may well be part of the southern extension of the zone within the Forlandsundet Graben, especially as seismic profiles between show evidence of a narrow basin in line between the two. Dallmann (1989) made it an extension of a fault through Recherchebreen and to the north. The succession (Thiedig et al. 1980) supplemented by Dallmann (1989) and a missing portion from the Thiedig et al. manuscript (Harland, Hambrey & Waddams 1993, pp. 100-104) comprises three formations. Renardodden Formation, > 217 m Skilvika Formation, 115.5 m Rochesterpynten Formation, 50-100 m at the base. The Rochesterpynten Formation is a complex unit investigated in 1975 when the whole section was measured by Harland & Pickton (Thiedig et al. 1979; Harland, Hambrey & Waddams 1993, p. 100). It consists very largely of Vendian-type diamictite clasts similar to those in the Kapp Lyell Group of the main outcrop and had been previously mapped as Precambrian basement. It was interpreted as a tectonosedimentary melange produced at an active fault scarp with very large slipped blocks of tilloid. The original large block of Precambrian tillite (the first Svalbard record) as described by Garwood & Gregory (1898) as the Fox Point tillite was not located. It was concluded that the blocks with large boulders derived from part of the (Vendian) Lyellstranda Formation no longer exposed, that it was probably of Paleocene age and had suffered some consolidation and tectonism before deposition of the overlying Skilvika Formation. Dallmann (1989) described the localities in some detail and postulated two faults separating the complex from older and younger rocks each with downthrow towards the Calypsostranda Group. It might thus be a Paleogene rejuvenation of part of an older fault system and/or initiated in the early stages of the West Spitsbergen Orogeny. Dallmann et al. (1993) mapped it as a splay of the Recherchebreen Fault. Skilvika and Renardodden formations have not been distinguished by age. Thiedig et al. (1979), on available evidence, argued a doubtful Paleocene age, but later work on dinocysts (Head, Manum & Throndsen 1986) suggested a Late Eocene to Oligocene age. Such a younger age was accepted by Steel et al. (1985) who plotted these strata as in a similar tectonic environment to Forlandsundet, but somewhat later, i.e. probably Oligocene. The succession is a dominantly coal-bearing clastic sequence of sandstones, siltstones and shales with a rich flora listed by Thiedig et al. (1979) who also reported the discovery of the trace fossils Ophiomorpha and bivalves Fellina and Conchocele couradii indicating occasional marine incursion into a delta (flat) sequence. Manum & Throndsen (1986, p. 116) noted that the coal reflectance data indicate a much higher rank than the coals of Forlandsundet. Two, possibly extreme, hypotheses to account for this are either an overburden of 6-8 km or a much higher thermal gradient resulting from neighbouring magmatic activity.

20.5.5

Offshore Paleogene sedimentation

Steel et al. (1985) summarized the seismic and DSDP evidence for a significant sediment wedge up to 7 km thick west of the Hornsund Fault and east of the Knipovitch Ridge and probably later than most of the deposits hitherto considered. This is partly because these strata appear to rest on new oceanic floor which would not have been available until the initial (Oligocene) spreading to form the Greenland-Norwegian Basin. This is complex story, mainly of Neogene events and will therefore be followed in Chapter 21.

398

CHAPTER 20

20.5.6

Thermal degradation of organic matter

(a) Preservation of palynomorphs. The relative preservation and abundance of palynomorphs in Svalbard varies considerably with location and age. Hughes, Harland & Smith (1976) outlined samples investigated as good, fair and poor and plotted these on a map (Fig. 20.6). From this pre-Eocene samples within the West Spitsbergen Orogen are poor, but post-Eocene samples from the graben were good. Results from ?Early Eocene and Paleocene through Carboniferous samples within the Paleogene Central Basin and Bjornoya were fair. Good results obtained from almost all Mesozoic to Carboniferous samples north and east of the Central Basin. A poor result from a Devonian sample in northeast Andr6e Land correlates with its position in a Svalbardian folded zone with some cleavage. The distribution tells a clear story, but the degradation processes may be complex. Buchan et al. (1966) had suggested (for the Central Basin data) one or more factors: depth of burial, proximity to igneous activity and dynamic metamorphism to which Hughes et aL added mantle heat flow related to distance from active spreading at plate margins. These are essentially thermal processes related to a tectonic environment. Manum et al. (1977) followed with criticism, especially of depth of burial, and argued from evidence of varied degradation within similar situations (e.g. comparing with vitrinite reflectance measurements) that there must be a diagenetic effect following on the vagaries of the sedimentary environment. Both factors clearly contributed in various circumstances and for example both Hughes et al. and Manum et al. agreed with 1/~

I~~

2d~

215~

3~~

~80~ I

79ON.--" RLS

O

~,ND

78~ ~

OYA

0 I

=

km

=

=

100 I

77ON~

~76ON

sequence

IVl

Mid-Tertiary ?Oiigocene ?Miocene

p

Lower Tertiary ?Eocene Paleocene

K

WestSpi~bergen Orogen

Cover

~75ON Palynomorph preservation

T

BJORNOYA

O

good

["'] poor /

Early Jurassic to Late Triassic Mid- & Early Triassic

(b) Vitrinite reflectance measurements. A more direct approach to depth of burial was by vitrinite reflectance studies - mainly of coal fragments. Coal occurs in Svalbard sediments of various ages as do palynomorphs. The American classification of coal rank (ASTM) follows with the boundaries between the ranks in approximate reflectance values (R0) from a table by Throndsen (1982): Peat/0.26/lignite/0.38/subbituminous: A, B & C/0.5/high volatile/1.1/medium volatile/1.5/low volatile/1.9/anthracite: semi/2.6/normal/5.0/meta-anthracite. The German divisions between Braunkohle, Steinkohl and Anthrazit being respectively at about R0 0.63 and 2.2. From a study of coals in the Todalen Member of the Firkanten Formation in the eastern part of the Central Basin around Longyearbyen Throndsen (1982) found a NE gradient with R0 values from about 0.8 at Grumantbyen, between 0.7 and 0.6 in the mines south of Adventdalen to about 0.4 near the Billefjorden Fault Zone. This led to a calculation of overburden of 2.5 reducing to 1.5 km over a distance of about 30 km with a sharp drop around Longyearbyen. Hence differential subsidence to the southwest of the Billefjorden Fault Zone and loss by erosion of up to 1.5 km of overlying strata. Michelsen & Khorasani (1991) reported a more extensive investigation throughout Svalbard and including also Carbonifereous, Triassic and Cretaceous coals which are also relevant to the interpretation of Paleogene tectonics as well as throwing light on their environments of formation. Serpukhovian coals at Trygyhamna and Bellsund within the West Spitsbergen Orogen yielded semi-anthracite coals of R0 = 2.02 compared with the Tournaisian high volatile coals near to Pyramiden (Birger Johnsonfjellet Member R0 = 0.89-0.91). Cretaceous coals from Adventdalen (N of Longyearbyen) are highvolatile bituminous A rank R0 ----1.01 rapidly and systematically decreasing to the north and east. The Tertiary coals were the main subject of study. Paleocene coals of (Ny-,&lesund differ from the Central Basin with no indications of marine influence, and are of high volatile bituminous rank C (R0 = 0.55) mainly of vitrinite. Late Eocene coals of the Forlandsundet graben have R0 = 3-4 due both to deep burial plus high heat flows. Whereas magmatic heat (e.g. Cretaceous sills) would not be uncommon, its effect appears not to have caused a significant regional thermal degradation. During Paleocene-Eocene subsidence, Carboniferous strata were rapidly heated to their maximum temperatures of around 190~ in western Spitsbergen and around 150~ in Central Spitsbergen, then slowly cooled during the uplift and erosion. This may have led to Tertiary or earlier gas generation from Carboniferous coals, but Paleogene coals had not approached thermal phase of cracking. Nyland et al. (1992), from a study of well samples, concluded that reflectance methods gave the most consistent results for calculating overburden in the southeastern Barents Sea. They found the greatest loss of >2000m to apply to a zone 100km wide including Bjornoya and extending northwards (presumably into the West Spitsbergen Orogen). This loss is consistent with the overburden estimate of Michelsen & Khorasani from R0 = 1.34 in the Tunheim Member coal in Bjornoya.

Permian to "middle" Carboniferous

Q ~ ) fair

MM

J

sequence

Eady Cretaceous Earliest Cretaceous to Mid-Jurassic

the implication 'that Tertiary sediments of significant thickness did not extend east of the present Spitsbergen Trough' (Manure et al., p. 129).

I

Old Red sequence

C

Early Carboniferous and Latest Devonian

D

Mid-Devonian to Earliest Devonian

Fig. 20.6. Map showing the geographic/stratigraphic distribution, preservation state and sedimentary facies of palynomorph assemblages (reproduced with permission of Cambridge University Press from Hughes, Harland & Smith 1976).

(c) Fission-track measurements. Nyland et al. from fission track data tentatively suggested two episodes for this uplift and erosion. The first (at 40-50 Ma) would correspond to the West Spitsbergen Orogeny and the second to a post-Miocene isostatic responsible to removal of ice. Blythe & Kleinspehn (1994) from apatite and zircon fissiontrack studies, concluded with evidence for Eocene cooling of Spitsbergen and the Barents Shelf.

PALEOGENE HISTORY

20.5.7

Sedimentation and erosion in a strike-slip regime

From what has gone before and from what follows it should be clear that Paleogene sedimentation and tectonics is dominated by strike-slip (transcurrence) with transpression and transtension between Svalbard and Greenland. The basins are responses to transtension and the orogenic structures to transpression. Otherwise the continuing strike-slip component is taken up by transcurrence, which may not leave a sedimentary or structural mark at least where the fault zone moves with pure strike-slip. Suffice to remark that a fairly comprehensive study from this point of view was contained in the paper by Steel et al. (1985).

20.6

Paleogene structures

Palaeogene structural events in Svalbard are most evident from west Spitsbergen, where basement and cover sequences are involved in broadly eastward-directed compressional deformation (the West Spitsbergen Orogen), including the Tertiary fold-and-thrust belt (Fig. 20.7). The West Spitsbergen Orogen (Harland & Horsfield 1974) was defined as a 300 km long belt, made of the western parts of Oscar II Land (plus Prins Karls Forland), Nordenski61d Land, the western tip of Nathorst Land, Wedel Jarlsberg Land and Sorkapp Land. It is bounded by the sea along the west coast, Kongsfjorden to the northwest, the northern platform to the northeast, and by the Central Basin in the east and southeast. Within the segment north of Isfjorden four zones have been distinguished (Harland & Horsfield). From the west, these are: (1) the western basement complex of Prins Karls Forland; (2) the Paleogene graben system of Forlandsundet; (3) the basement zone of western Oscar II Land; and (4) the fold-and-thrust belt of eastern Oscar II Land. Zones 1 and 3 are formed mainly of pre-Devonian strata, Zone 2 of Paleogene strata and Zone 4 of Carboniferous through Early Cretaceous rocks. Zones 1 and 3 show effects of some pre-Carboniferous and of Paleogene deformation whereas in zones 2 and 4 tectonism was demonstrably Paleogene. (5) A fifth zone may be added to the above to accommodate the folded Permian and Triassic strata of Sorkappoya and Tokrossoya. This only appears in the extreme south. It appears to trend offshore west of zone (1) and/or (3) but the continuation further north in relation to that of the Prins Karls Forland zone (1) is problematic. Zones 3 and 4 are continuous southwards, hence dividing the full length of the orogen into two main belts; a western basement zone (Western Basement High of Dallmann et al. 1993) and an eastern fold-and-thrust belt. The latter is divided from the Central Basin by a thrust front, which in effect marks the eastern edge of the orogen, although adjacent parts of the Central Tertiary Basin are also slightly deformed. Concommitant deformation has also been recognized on the Billefjorden and Lomfjorden fault zones to the east, and syn- or post-orogenic extension created the Forlandsundet Basin, which separates Prins Karls Forland from Spitsbergen. Bergh, Braathen & Andresen (1997) described the western basement interaction, the central thin-skinned tectonics and the eastern thrust structures, with a 20 km shorten in Oscar II Land.

399

The time sequence and regional tectonic context of these structures will be attempted in Section 20.7 below.

20.6.1

Western basement zone, including Prins Karls Forland

Apart from the Paleogene graben system (e.g. Forlandsundet) there is no direct stratigraphic evidence as to the age of the structures within this zone.

Prins Karls Forland, an elongate island 85 km in length but never more than 12 km in width, consists of rocks (the Forland Complex) of groups probably of Vendian through Silurian age. The conspicuous fold and thrust structures verge to the west or southwest (Atkinson 1960; Manby 1986). Their deformation was certainly post-Vendian and probably post-Silurian. There was probably a postVendian pre-Silurian tectono-thermal event which metamorphosed the Scotia and earlier groups as identified in the Sutorfjella conglomerate clasts in the Barents Formation of the Grampian Group. By correlation with Oscar II Land the Barents Formation might be coeval with the Bullbreen Group and the earlier schistosity might be equivalent to the Eidembreen Event of early to mid-Ordovician age. No earlier tectonism is evident in the island, nor has there been any clear demonstration of Silurian or Devonian tectonism of significant intensity on the mainland. The western province, to which the basement of Oscar II Land belongs, was probably beyond the range of the Caledonian Orogeny at that place and time. The simplest hypothesis is that the conspicuous fold and thrust structures correspond to the established Paleogene structures of the West Spitsbergen Orogen in Oscar II Land as was concluded in section 9.8 above. The failure of Manby to distinguish his D1 and D2 except in detailed structural fabrics, makes it likely that his two folding events which he said were coaxial, but without stated criteria to distinguish them, might well be phases in one orogeny. If this argument stands then the hypothesis of Lowell (1972) for a dextral transpressive (flower) structure rooted in the Forlandsundet Graben may yet be justified (Fig. 9.10). As concluded in Chapter 9 the 'basement' is largely of Precambrian rocks which were probably metamorphosed in Ordovician time and the lower groups in the south arched in Paleogene time when the late Vendian, and the supposed Early Paleozoic strata were overfolded and thrust over the lower groups.

Forlandsundet. The intense dextral strike-slip Kaffiayra m61ange on the east side of the sound suggests a potential root zone within the orogen.

Oscar II Land. On Broggerhalvoya the northernmost part of the orogen is exposed, both basement and cover rocks are involved in large-scale stacked nappes. Because these structures are confirmed stratigraphically as post-Paleocene, Broggerhalvoya is described with the rest of the fold-and-thraast belt in Section 20.6.2. Mention is again made here of the observations noted in Chapter 9 where the analysis of verging structures in Bullbreen

Fig. 20.7. Schematic cross-section of the northern segment of the West Spitsbergeb Orogen, with a conjectured root zone in the Forlandsundent Graben. The sequence of events, with subsequent normal faulting, cannot be shown in one sketch (after Nottvedt, Livbjerg & Midboe 1988).

400

CHAPTER 20

Group strata north and south of St Jonsfjorden by Ratliff et al. (1988), that they took to be mid-Paleozoic, could equally well be argued to be mid-Paleogene. This includes evidence of a NW-SE zone with dextral strike-slip. Between Engelskbukta and St Jonsfjorden is a complex eastern margin to the graben. The flattish terrain of Sarsoyra and Kaffioyra exposes disordered hillocks of older rocks interpreted by Ohta et al. (1995) as a dextral shear zone with slices of rocks to the Vestg6tabreen Complex south of St Jonsfjorden. These are bounded to the east by the Sarsoyra Formation, a strip of Ordovician-Silurian strata also matched to the south near Motalafjella, and also previously considered to be Carboniferous. Just north of St Jonsfjorden and southwards as far as Eidembreen there are low angle thrusts (with klippen) of Vendian, Ordovician and possibly Silurian strata resting on Vendian rocks. They dip westwards and apparently verge eastwards. The thrusting is later than the mid-Ordovician tectonism. That in the coastal cliffs of the same mountains (in Skipperbreen) are wedges of Carboniferous strata involved in the tectonism supports an observation (W.B.H.) of a sliver of coral-bearing rock (probably of Carboniferous but conceivably of Early Paleozoic age) in the main thrust surface. Just north of Eidembukta is a wedge of fossiliferous Carboniferous rocks faulted in with the Vendian strata. South of Eidembukta at Farmhamna, vertical fossiliferous Carboniferous strata are subparallel to Vendian strata on which they appear to have rested unconformably. Still further south at Daudmannsoyra is a well exposed infaulted sliver of fusuline bearing limestone. These occurrences are adjacent to, and analogous with, the main Paleogene graben immediately to the west. The map interpreting the Vendian outcrops of Oscar II Land (Fig. 9.2, from Harland, Hambrey & Waddams 1993, p. 56) shows a projected thrust fault trending approximately NW and probably verging NNE as with Broggerhalvoya to the north.

Nordenski61d Land. South of Isfjorden the older (Vendian) outcrop occupies the strandflat (Nordenski61dkysten) east of which is a mountain range formed of steeply dipping Carboniferous strata, resting unconformably on the Late Proterozoic rocks and marking the western boundary of the fold-and-thrust belt. The structures in the older rocks have been tentatively shown (Figs 10.2 & 10.3) in schematic outcrop with a somewhat similar fault trending NW-SE with a postulated thrust vergence to the NE. On the south side of the fault are two elongate outcrops of Early Carboniferous rocks appearing as small graben or half-graben (Harland et al. 1993, p. 87).

Wedel Jarlsberg Land. To the northeast of Kapp Lyell is the Calypsostranda outcrop, a graben or half-graben trending NW-SE. This may be in line with the Forlandsundet graben (zone 2 above), a suggestion reinforced by submarine evidence of a further basin structure between the Paleogene outcrops. Dallmann (1989) showed the fault trace extending south into the Recherchebreen fault system. Further south the NNE-SSW-trending Orvindalen Fault shows an apparent dextral displacement of 5-10km and similar trending faults are necessary beneath the larger Torellbreen glaciers, but their nature has yet to be elucidated. Apart from the faults, the broad plunging syncline in the north and the extremely complex fold system in Vendian and older rocks of western Wedel Jarlsberg Land could well be Paleogene but cannot be constrained decisively. East of Hansbreen (in the Central Province) the main deformation of Vendian, Cambrian and Ordovician basement in east-vergent thrusts must be excluded from Paleogene consideration. They are demonstrably pre-Triassic and probably Silurian in age. Far more intense tectonism is demonstrably Proterozoic as seen in the protobasement with the Nordbukta, Isbjornhamna and Magnethogda groups. Mid-Cretaceous dykes ( l l 0 + 5 M a ) and a possibly younger intrusion (66.8 + 4.3 Ma) as determined by Vincenz et al. (1981) in

connexion with palaeomagnetic investigations in the Vimsodden area of Wedel Jarlsberg Land, have suffered minor strike-slip faulting during the Paleogene orogeny (Birkenmajer 1986, 1993c). His 1993 paper discussed other deformation events in the Western Basement Zone. He argued for strong Caledonian or preCaledonian folding. According to the interpretation in this work, o n l y Paleogene or pre-Caledonian (sensu stricto) folding is postulated, namely Ordovician and ?Mesoproterozoic for the preElveflya Formation rocks. This could be a test case for this aspect of the conflicting hypothesis. According to the interpretation in this work, the VimsoddenKosibapasset Fault (VKF) of Czerny et al. (1992) is a faulted unconformity and would thus be a major NE-vergent thrust in the Paleogene orogeny.

Sarkapp Land. Most of the east of Sorkapp Land is occupied by the fold-and-thrust belt (see below). The central core of Precambrian and Early Paleozoic strata was largely unaffected by Paleogene movements because the extensive westerly dipping thrusts are truncated by flat-lying Triassic strata. The basement zone here appears to have been relatively rigid. However, southwest of Oyrlandet and in Sorkappoya is a fold belt, possibly merging southwards with the main fold-and-thrust belt, but striking NW-SE and projecting offshore. The Norsk Polarinstitutt map C13G (Winsnes et al. 1992) shows cross-sections with gently westward dipping thrusts through the zone west of the fold-andthrust belt and thrusting Triassic over Jurassic strata. This is zone (5) mentioned above (p. 399).

20.6.2

Fold and thrust belt

The belt extends for approximately 300km in a NNW-SSE direction from NW Oscar II Land to Sorkapp Land, but is never more than 30km wide and in some cases less than 10km wide. It is bounded by the basement zone to the west, and by the northern platform and Central Tertiary Basin to the east. Although Tertiary deformation has affected both those two elements, most of the deformation and shortening associated with the West Spitsbergen Orogeny is observed in the Carboniferous through Paleocene strata of the fold-and-thrust belt. The first detailed study over almost the whole belt was by the late A. Challinor between 1960 and 1969 as part of the Cambridge Svalbard Exploration Programme. His crosssections, based on mapping by the group and hitherto unpublished, have been simplified and are presented in Fig. 20.8a, b. Challinor's sections, although not balanced, provide a good insight into the overall structure of the orogen and the variation in structural styles from north to south. The work was done at a time before current terminology was applied to fold-and-thrust belts, but even so, some of these elements can be identified from his sections and most notably the ramp-flat geometry characteristic of a variable competence layered sequence.

Oscar II Land. The fold-and-thrust belt in Oscar II Land is extensively exposed, with a maximum width across strike of 30 km and length of 80 km (Harland & Horsfield 1974). The region can be sub-divided into three zones on the basis of the Tertiary structures present (Maher 1988). In the west is the basement-involved fold and thrust zone; in the centre a thin-skinned fold belt with minor thrusts; and in the east a thin-skinned thrust belt. The eastern zone marks the thrust front to the belt, although not the easternmost limit of Tertiary deformation. The most studied parts of Oscar II Land are Broggerhalvoya, St Jonsfjorden and LappdalenMediumfjellet, in the western, western/central and eastern zones respectively. On Broggerhalvoya the orogen is unusual in that it trends WNW-ESE (as opposed to NNW-SSE everywhere else). It involves both basement and cover rocks (Orvin 1934; Challinor

PALEOGENE HISTORY 1967) with little tectonic contrast between them. Three nappe complexes are exposed there, characterized by duplex structures in lower nappes, and fold pairs and imbrication in the upper nappe. They overthrust the Paleocene coalfield to the extent that drift mining extended about 1 km beneath the thrust front (Hanoa 1993). At least 18 km of shortening has been accommodated within the stack, with 12km in the uppermost nappe (Manby 1988). In the NW of the peninsula the rocks are mainly post-Devonian; in the SE pre-Devonian (mainly Vendian and Sturtian) rocks predominate. Movement directions in the NW are more northerly than elsewhere, and in the SE are northeasterly; the two zones are separated by a major N-S sinistral transfer zone. The variation in vergence direction can been attributed to either (i) the structures being at a restraining edge of dextral transpressive motion in contrast to the remainder of the belt that would be parallel to the strike-slip component or (ii) to movement over an oblique/lateral ramp, possibly formed by a basement buttress, within a dominantly WSW-ENE orthogonal convergence model (Maher 1988). These models are discussed more fully in Section 20.7. In the Vegardfjella-Wittenburgfjella area of southeastern St Jonsfjorden the western zone of basement-involved thrusting and the central zone of NE-verging folds are exposed (Maher & Welbon 1992; Welbon & Maher 1992). The basement-cover rocks involved are mainly of Permian and Triassic age deposited in the St Jonsfjorden Trough (Gjelberg & Steel 1981). The thrust system consists of three major detachments, at least one of which may represent an earlier basin fault that has been reactivated (Maher & Welbon 1992). The two lower thrusts are rooted within and carry basement rocks, and cut up to a roof thrust with at least 3.2 km of displacement. Ramp-flat geometries prevail with flats commonly in the Gipshuken Formation evaporites. The zone of folding to the east is 8 km wide and also affects Permian and Triassic strata. The structural geometries indicate that deformation is controlled by underlying thrusts, with slip transferred along a basal detachment in the Gipshuken Fm gypsum. Total shortening in the area was estimated to be approximately 13 km (Welbon & Maher 1992). The most studied parts of the eastern thrust zone and thrust front are in the Lappdalen-Mediumfjellet area (see synthesis of Bergh & Andresen, 1990). Four thrusts are present in each of the two localities; each associated with large- and small-scale thrusts and folds. Deformation is generally characterised by structural variability within different stratigraphic levels, i.e. stacked ramp-fiat geometries with fault-propagation (tip-line folds) and fault-bend folds, out of sequence thrusting, and decollementhorizons within the Permian Gipshuken Formation gypsum and Triassic Botneheia Formation shales. Displacements on the main thrusts vary from 200 m to over 1 kin, with a total shortening of at least 4 kin. The upper-most thrust at Lappdalen cuts down-sequence in the Gipshuken evaporites, and at Mediumfjellet the top thrust is out-of-sequence. Bergh & Andresen (1990) proposed that the thrust front formed as an eastward-vergent in-sequence (piggy-back) thrust belt, that was then cut by out-of-sequence thrusts that gave rise to an apparently hinterland-dipping duplex. Along the southern edge of Oscar II Land lies the NE-SW oriented Isfjorden Fault zone (Harland & Horsfield 1974; Ymerbukta Fault of Ohta et al. B9G, 1991), which separates intensely deformed Mesozoic rocks to the NW from sub-horizontal Cretaceous to Tertiary rocks in the SE. The fault has been interpreted as an oblique ramp with a vertical displacement of approximately 400m (Bergh et al. 1988; Bergh & Andresen 1990), and is one of many such features within Oscar II Land (Dallmann et al. 1993). The marked contrast between the fold belts north and south of Isfjorden cannot be explained simply by a fault. It is probably the result of thrusting to the north against the relict Nordfjorden Block. This is replaced south of Isfjorden by the Paleogene basin which provided no such barrier. Therefore, south of Isfjorden some of the east-vergent movement took the form of bedding thrusts within incompetent strata beneath the Paleogene Van Mijenfjorden Group. They did however surface in thrust structures along the Billefjorden and Lomfjorden Fault zones. One difference between north and south is that the d6collement zone to the north was

401

effective in the Gipshuken Formation evaporites, whereas to the south Mesozoic shales provided the medium. Nevertheless total stratal shortening north of Isfjorden was probably greater.

Nordenskiiild Land. Western Nordenski61d Land comprises three zones: the western basement high, the central fold belt, and to the east the Central Tertiary Basin (Orvin 1940). The fold belt, approximately 40 km long and 9 km wide, affects a 3.7-5 km thick sequence of Carboniferous to Tertiary strata that lies unconformably upon Late Proterozoic metamorphic basement (Hjelle et al. 1986). Its eastern edge is largely hidden beneath Gronfjorden and Fridtjovbreen. It is the highest exposed level of the fold-and-thrust belt in west Spitsbergen (Dallmann et al. 1993). The Permian Kapp Starostin Formation forms a marker horizon across the fold belt and is most conspicuously affected by the deformation; the presence of Paleocene rocks within some of the folds proves the event to be of Tertiary age. In general, the strata are deformed into open, upright anticline-syncline pairs or monoclines, with amplitudes and wavelengths on the scale of hundreds of metres (Maher, Ringset & Dallmann 1989). Folds are oriented NNW-SSE and commonly plunge to the north or in some cases to both north and south; axial planes are usually upright or have a slight westerly inclination. The average transport direction is 060 ~. Figure 10.8 compiles and simplifies the map and sections by Braathen, Bergh & Maher (1995) interpreting the structure of the whole fold belt in Nordenski61d Land. Whether or not the detailed projections upwards and downwards are justified is not the point. The contribution is a 3D presentation of this remarkable and accessible structure. A distinctive feature of this study is a longitudinal (N-S) section in addition to several transverse (E-W) sections. This shows a northward component of vergence to complement the ubiquitous eastward component. It is thus consistent with dextral transpression; but whether partitioned in time is not clear. Figure 15 of Braathen et al. (1995) is repeated here as Fig. 20.10. Braathen & Bergh (1995) discussed some further structural implications.

Wedel Jarlsberg Land and Nathorst Land. The fold belt in Wedel Jarlsberg Land and Nathorst Land is east of the terrane boundary from Recherchefjorden to Hansbreen and east of the 'Hornsund High' with dominant eastward-verging Caledonian folds and thrusts that comprise the western basement high. A series of overlapping thrust zones occurs through Midterhuken at the western tip of Nathorst Land (Fig. 10.9) and central Wedel Jarlsberg Land (Dallmann 1988a; Dallmann et al. 1993). The kinematics of some of these have been described and discussed, principally the Bravaisknatten thrust zone on Midterhuken (Maher, Craddock & Maher 1986; Maher 1988; Ringset 1988; Maher & Welbon 1992), the Berzeliustinden thrust zone (Dallmann 1988a, b), the Supanberget area thrusts (Dallmann & Maher 1989), and the northern Hornsund area (Kvalfangabreen-Adriabukta; Dallmann 1992b). There is a common pattern at all localities of eastward thrusting, rooted in basement, repeating and/or overturning platform strata with large associated folds, in places recumbent, and shortening of up to 2 km. The main phase of thrusting was followed by folding and by later extensional faulting. As in the St Jonsfjorden area of Oscar II Land variations in the thickness of Carboniferous strata and internal unconformities suggest an original basin-graben structure (Maher & Welbon 1992), which may have also controlled the Paleogene geometry. The fold belt is exposed especially well both north and south of Hornsund. East of Hansbreen (E of the main Precambrian terrane) strata dip westward but young eastward and with steep east-verging thrusts. There is a remarkable sequence: Vendian through Cambrian, Early Ordovician, Devonian, Carboniferous, Permian, Triassic, Jurassic, Cretaceous and Paleogene. There are of course minor breaks and there appear to be unconformities at least at the initial Devonian and Paleogene boundaries.

402

CHAPTER 20

(.)

South of Hornsund flat-lying Triassic strata rest unconformably on, and truncate the, older strata so that there is good evidence that the main deformation was probably Silurian (Caledonian). However, the style is similar through the basal Devonian unconformity and as far as the open folding of the Cretaceous terrane. At least this eastern part was subject to Paleogene deformation and it would seem that Caledonian structures were also reinforced in Paleogene time. In general, the more southerly exposures represent higher structural levels than in the north, with Mesozoic and Paleocene strata involved as well as the Late Paleozoic successions. One notable difference of the structures in Wedel Jarlsberg Land and Nathorst Land is that detachment surfaces do not occur within evaporite horizons of the Gipshuken Formation, as such lithologies did not develop in the area. Instead, flat thrusts appear to be controlled by shale horizons in Carboniferous and Early Permian strata, and as these horizons are discontinuous they may also control the locations of the frequent ramps present, such as those that occur in the Supanberget area (Dallmann & Maher 1989).

PRINS

KARLS

~,///

/

///////

79~

3

6~

Sorkapp Land divides into five zones from west to east: /

"\

'i2-E

/

(i)

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...., .

(ii)

/

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/

(iii)

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L

L

s

U

N

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HORNSUND '~

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_--------- 27

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Deformation in the fold belt is most intense around Hornsund, and decreases southwards to the point where it is manifest only as a single monocline. Part of the fold-belt is formed by a broad syncline in Devonian and Carboniferous strata, named the Samarinbreen Syncline (Dallmann 1992b). The eastern limb of the syncline becomes more tightly folded towards the edge of the fold belt, and involves Carboniferous to Cretaceous rocks. Large-displacement thrusts are present in the area. Folds have inclined to recumbent axial surfaces with eastward vergence where this is shown. Dallmann (1992b) described the structural evolution of the area in terms of wedge insertion and backthrusting followed by foreland-directed thrusting and associated folding. The positions of the faults are probably controlled by pre-existing structures relating to Caledonian and Adriabukta (Carboniferous) events. The western fold belt of Tokrossoya and Sorkappoya is certainly Paleogene and could well have compensated in the south for the decreasing southerly contraction of the main fold belt.

:/

20.6.3

~" ~

./" l

a fragment of a western fold belt deforming Permian and Triassic strata as seen in Tokrossoya and Sorkapppoya and trending NNW-SSE offshore; a triangular area of flat-lying Carboniferous and Triassic strata west of the Hansbreen Fault Zone; the main Caledonian fold and thrust belt forming the higher mountains and indeed a reactivated Caledonian basement; the main eastern fold and thrust belt with Paleogene deformation of the Devonian through Jurassic strata; a wide outcrop of gently folded Cretaceous strata appearing through ice fields and just touching the Paleogene of the Central Basin in the easternmost outcrops.

25km

I

/

/:18~ Fig. 20.8. (a) Map showing the location of selected unpublished structural profiles of the West Spitsbergen Orogen. (b) Unpublished cross-sections of the West Spitsbergen Orogen from large scale sections surveyed by A. Challinor 1960-1969.43 sections from Broggerhalvoya to Sorkapp Land selected, simplified and reduced by C. Townsend and L. M. Anderson.

West Spitsbergen Paleogene graben

The West Spitsbergen Paleogene graben system includes the Forlandsundet Graben, the submarine line to the south, and the Calypsostranda ?half graben. The first and third of these have reasonably dated Paleogene strata already discussed. The Forlandsundet Graben contains evidence of deformation of both Paleozoic and Paleogene strata (both early Paleocene and the mainly extensional faults forming half- or full-graben structures of Gabrielsen et al. 1992) as well as probable late or post depositional deformation in an overall transpressive regime. Tectonic models for basin formation generally involve several phases of extension and compression, all with a strike-slip component (e.g. Harland 1979; Lepvrier & Geyssand 1985; Steel et al. 1985; Lepvrier 1990a, b; Gabrielsen et al. 1992). Movement occurred along basin boundary faults rather than within the basin itself. Several strike-slip models

PALEOGENE HISTORY

403

(b) KEY TO UNPUBLISHED STRUCTURAL PROFILES OF THE WEST SPITSBERGEN OROGEN

Van Mijenfjorden Gp

Adventdalen Gp

Kapp Toscana and Sassendalen gps

Tempelfjorden and Gipsdalen gps

Billefjorden Gp Devonian

CZ A

Aspelintoppen Fm

Cz F

Firkanten Fm

Kc KH

Carolinefjellet Fm Helvetiafjellet Fm

Kj Jj

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TKT TSK Tv

Kapp Toscana Gp Sticky Keep Fm Vardebukta Fm

PKS

Kapp Starostin Fm

PG

Gipshuken Fm Nordenski61dbreen Fm

CpN CBT

.........................

Formation boundary Top of Kapp Starostin Formation

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Extensional fault

Br~ggertinden Fm

Co

Orustdalen Fm

CA

Adriabukta Fm Marietoppen Fm

DMA

Group boundary

++++++++++++++++++i

ere-Devonian basement + + + + + + + + + + + + + + + + + + ++++++++++++++++++

No vertical exaggeration Horizontal = Vertical

404

Fig. 20.8(b). (continued).

CHAPTER 20

PALEOGENE HISTORY

Fig. 20.8(b). (continued).

405

406

Fig. 20.8(b). (continued).

CHAPTER 20

PALEOGENE HISTORY

Fig. 20.8(b). (continued).

407

408

Fig. 20.8(b). (continued).

CHAPTER 20

PALEOGENE HISTORY have been presented for the formation of the basin, including a suggestion that it may have formed by pull-apart within a relay zone between two NW-SE-trending dextral strike-slip faults situated offshore (Lepvrier 1988, 1990). It is concluded here that the whole development was in a dextral strike-slip zone. There was a pre-orogenic transtensional basin which was compressed in the orogenic climax in which the dextral transpression (shearing of the Kaffioyra Zone) continued into further transtension with further deposition. Then there was further minor transpression before the strike-slip motion may have been largely transferred to the west of the orogen.

20.6.4

Structures of the Eastern Platform and Central Basin

Billefjorden Fault Zone was first recognized as a significant strikeslip tectonic lineament extending through Spitsbergen by Harland (1969), although sections of it had previously been described (e.g. McWhae 1953). Its major strike-slip history was primarily Silurian and Devonian followed by intermittent extensional dip-slip movement, with Carboniferous through Jurassic sedimentary control. The fault zone then located Paleogene reactivation with thrust structures in the cover strata (Permian through Jurassic) and followed later by further normal dip-slip faulting (Parker 1966; Harland et al. 1974; Ringset & Andresen 1988). Generally not observed as a single fault, the zone usually consists either of a series of parallel faults, or of N-S-trending folds that are regarded as having formed above a hidden fault. For example, north of Isfjorden, several large extensional faults occur within a zone up to 3 km wide, cutting Devonian and Carboniferous strata (Harland et al. 1974; McCann & Dallman 1995). The faults appear to have had an original eastward extensional throw but have been reactivated with reverse movement. Most of the fault zone traverses pre-Paleogene terrane, nevertheless a Paleogene age for the renewed activity is conjectured because no other age would match the evidence. On the south side of Isfjorden in eastern Nordenski61d Land, the continuation of the fault zone is marked by a series of folds inferred to lie above faults. This was illustrated by Parker (1966, 1967) who distinguished clearly between contemporaneous Mesozoic movement and presumed Paleogene folding and thickening (see Figs 4.4 & 19.4). The strata either side have been affected by small-scale imbricate and duplex structures and by decollement zones (Haremo et al. 1990; Haremo & Andresen 1992; Haremo, Andresen & Dypvik 1993). The folds consist of two east-facing anticlines within Late Jurassic and younger sequences; to the north the folds are replaced by a thrust with minimum shortening across it of 1.5km. Underlying rocks of the Lower Janusfjellet Subgroup contain imbricate and duplex structures, but no evidence of the folds. This has been interpreted by Haremo and co-workers as evidence of a decollement zone situated at the top of the Janusfjellet Subgroup. A second d~collement has been interpreted to lie beneath the Jurassic sequences, as underlying Triassic rocks of the Sassendalen Group also contain imbricate and duplex structures. The zone in that area therefore preserves structures related to both thin- and thick-skinned deformation, controlled by the inferred presence of steeply dipping Paleozoic faults that were reactivated. Lomfjorden Fault Zone. Along most of its length, the Lomfjorden Fault Zone has a down-to-the-east displacement, but the dip of the fault varies from east to west. As with the Billefjorden Fault Zone, it may have Paleozoic origins, but without major strike-slip and with some Paleogene reactivation. The youngest strata affected are of Early Cretaceous age, and no Tertiary strata are exposed close to the fault. But as there is no evidence for Late Cretaceous deformation, a Paleogene age must be the most likely and so related to the West Spitsbergen Orogeny. The southern end in the Agardhdalen area has been studied (Andresen, Haremo & Berg 1988; Andresen et al. 1992; Haremo & Andresen 1992). The

409

Mesozoic sequence exposed there is deformed into an east-facing (verging) asymmetric anticline/monocline, with a total uplift of the west side with respect to the east of 500 m. The fold was considered to relate to a westdipping reverse fault at depth. The fold rotates small-scale reverse faults (within imbricate and duplex systems) situated in the Triassic Sassendalen Group, and similar structures occur to the south within the Janusfjellet Subgroup. Andresen et al. (1992) considered these zones to indicate the presence of decollement horizons at the same stratigraphic levels as at the Billefjorden Fault Zone, namely near the base of the Janusfjellet Subgroup and near the top of the Sassendalen Group (Botneheia Formation). The Central Basin immediately east of the fold-and-thrust belt is slightly deformed by the West Spitsbergen Orogeny. Along the western basin margin the strata dip between 5~ and 25 ~ east, and in places (e.g. Sorkapp-Hornsund area) broad low-amplitude folds occur within the basin (Dallmann 1992b). Thrust faults are rarely seen at surface but have been inferred at depth, particularly beneath surface anticlines, in seismic sections (e.g. at Grimfjellet in Torell Land; Orheim et al. 1988). The presence of the decollement horizons at equivalent levels adjacent to the Billefjorden and Lomfjorden fault zone and the minor folds and thrust splays within the basin, has suggested to some workers (e.g. Andresen, Haremo & Bergh 1988) that the decollements may extend beneath the entire basin. Nordfjorden Block plunges south beneath the Paleogene strata of the Central Basin. Whereas it appears that stresses f r o m the West Spitsbergen Orogeny in the west were transmitted to the east in bedding-thrust zones beneath the Paleogene cover, to the north similar structures can be observed at the surface where the Gipshuken evaporites preserve the evidence of the orientation of the ENE vergence (Harland, Mann & Townsend, 1988). At this latitude the thrust zones, with evident deformation at the Billefjorden Fault Zone (which bounds the Nordfjorden Block to the east), do not dip into the Billefjorden Trough where the lower gypsiferous strata escaped deformation in this way.

20.6.5

Paleogene structures in north and northwestern Spitsbergen

Structures in this area were considered in Chapter 8 where two structural elements were concluded to be the consequence of the West Spitsbergen Orogeny with its northeast vergence. (i) The sinistral offsets of the Raudfjorden and Breibogen faults of up to 2 km at about 3 latitudes. (ii) The deformation of post-Devonian lamprophyre dykes, isotopically dated at about 309 Ma in Pennsylvanian time, with Devonian cleaved strata necking the dyke with some cleavage (Manby & Lyberis 1992). This is a little further north than Kongsfjorden where Paleogene northeast-verging thrusts were active. As with the Billefjorden Fault zone to the south, Paleogene reactivation in a thrust regime is typical. However, it has been claimed that many more structures, herein attributed to Early and Late Devonian deformation episodes, may be Tertiary (Manby 1988) or post-Caledonian (Thiedig & Manby 1992; Manby & Lyberis 1992; Manby et al. 1994). In Chapter 3 it was argued that West Spitsbergen Orogeny tectonism was mainly Eocene and not Late Cretaceous or early Paleocene as suggested by Lyberis & Manby (1993). The structures in Devonian strata east of the Breibogen Fault have been claimed to be Svalbardian, i.e. Late Devonian (e.g. in Chapters 8 and 16). They are demonstrably so in the south where they are truncated by unconformable Tournaisian or even latest Famennian strata, and exhibit westward-verging folds and thrusts. Similar verging structures are found in the north without the age constraint of the cover. There is no reason to suppose otherwise, since the deformation dies out westwards and the Paleogene deformation would be most intense in the west and eastward verging. Critical support for a Paleogene age might be taken from Manby & Lyberis (1995), who note that vertical N-S pressure solution cleavages imply a greater overburden than the available

410

CHAPTER 20

Devonian strata should have provided and that cover strata of presumeably later Paleozoic and Mesozoic strata provided the necessary overburden. There are two uncertainties in this argument. (i) There was probably more Devonian sediment at that time than presently preserved and the overburden could have been doubled by tight folding. (ii) There may have been no Mesozoic or even Permian strata there by Eocene time because the evidence from the sub-Paleocene unconformity is that the north of Spitsbergen was uplifted gently in late Cretaceous time so that late Albian strata are preserved in south Spitsbergen and with a tilt of less than 1~ All Mesozoic strata were removed at the northern margin of the Ny-Alesund coalfield. If the northward uplift was tilted only half a degree another 50 km to the north, another 2 or 3 km of Btinsow Land Supergroup rocks would have been eroded. Mesozoic sedimentary facies maps confirm such a source of sediment in the north by Barremian time. The situation west of the Breibogen Fault was different with Early rather than Late Devonian deformation. In the southwest, where Manby (1988) and Thiedig & Manby (1992) suspected postDevonian (Paleogene) deformation on Blomstrandhalvoya, the age of the deformation cannot be constrained and that it could be Svalbardian (here considered more likely Haakonian, i.e. early Devonian). The thrusting verges westwards, which would favour Devonian over Paleogene deformation. On the other hand, although the structure and sedimentation of Blomstrandhalvaya fits the Haakonian N-S strike-slip fault model, it is likely that the north to northeast thrusting a few kilometres to the south in Broggerhalvoya had some effect and the extensive calcite veining might thus be Paleogene.

20.6.6

Offshore northwest Spitsbergen

The Yermak Plateau, Sjubrebanken, Danskoya Basin and Norskebanken have been introduced in section 8.6 above. These features, and the Yermak Plateau in particular, probably developed as a submarine volcanic province (mainly Late Eocene-Early Oligocene) after Anomaly 18 when Spitsbergen, Greenland and the Lomonsov Ridge were separating (at what has been referred to as a triple junction) and completed by anomaly 13 (Jackson et al. 1984). That is the area where (i) the dextral strike-slip zone (De Geer Line) separating Svalbard and Greenland meets (ii) the Nansen-Gakkel spreading ridge of the Eurasian Basin and (iii) the sinistral strikeslip zone postulated between Greenland and Ellesmere Island (once referred to as the Wegener Line). This is not well documented. It may have been a rather wider zone expressing the sinistral transpression in the Eurekan Fold Belt of Ellesmere Island.

20.7

This was an essential option in the original transpressive concept; whereas Maher & Craddock (1988) presented the same 'decoupling' mechanism as an alternative to transpression. In their context, partioning and decoupling are the same (Fig. 20.9). The Paleogene story is thus one of dextral strike-slip along the De Geer lineament with intermittent and sporadic transpression and transtension. The development begins with a tendency to transtension so allowing subsidence for the development of the earlier Van Mijenfjorden Group in the Central Basin. The West Spitsbergen Orogeny resulted from a transpressive collision between Svalbard and eastern North Greenland. Faleide et al. (1991) described this as a well-constrained dextral displacement along the De Geer Line of 550 km, with partitioning into 'a tangential low stress strike-slip component and a normal high stress compressive component forming the fold and thrust belt'. Subsequently at about Anomaly 13, the same dextral strike-slip progression resulted in simple transcurrence or transtension, with the active opening of the Greenland and Norwegian basins as Svalbard moved south with respect to Greenland. West of Svalbard and southwest of Bjornoya compressive structures collapsed into margin-parallel grabens. The relating structures, especially in the fold and thrust belt, are conspicuously compressive with ENE vergence in Spitsbergen. This direction was more precisely confirmed by the long axes of anhydrite bodies in the Gipshuken Formation (Harland, Mann & Townsend 1988). Mention has been made of occasional evidences in the orogen of a dextral transpressive component. However, in general, it must be assumed that the dextral strike-slip progression was nearly continuous, as indicated by the oceanic magnetic anomalies. Of particular interest is the Broggerhalvoya virgation in which the fold belt swings round from a NNW-SSE to a NW-SE and WNW-ESE trend, with corresponding swing in the vergence of overthrusting almost towards the north. Lyberis & Manby (1993) calculated a 40 km shortening based on deformation of Carboniferous and Permian strata and possibly more if the pre-Carboniferous rocks are considered, as they are intimately involved in the thrust structure. This direction cannot thus be a minor deflection in

cy

Structural sequence

The stratigraphic timing of tectonic events is poorly constrained as is evident from the variety of opinion indicated on Fig. 20.11. These paragraphs attempt only to distinguish the structural sequence in terms of relative movements between the Greenland and BarentsBaltic plates. There is little doubt that the overall Paleogene story concerns the mobile zone between these plates. Late Cretaceous uplift and some magmatism heralded the thermal separation of the two plates by initial spreading of the Eurasia Basin along the Nansen-Gakkel Ridge at the northern end of a transform fault system, the southern continuation of which compensated the motion by (further) opening of the North Atlantic, Greenland and eventually the Norwegian basins. No sequence of relative lithospheric plate movements throughout a significant sector of the globe is possible without some segments of mobile belts being oblique rather than perpendicular or parallel to relative plate transport. Thus zones of transpression and transtension are inevitable although they may be reflected structurally in a variety of ways including partitioning into component orthogonal components (Fig. 20.9; Harland 1971).

\.

,,)

%.... S

SINISTRAL

DEXTRAL

Fig. 20.9. Schematic model illustrating possible structural configurations within an area of strike-slip deformation, tc, transcurrence (pure strike-slip); cp, compression; xt, extension; tt, transtension; tp, transpression.

PALEOGENE HISTORY FESTNINGEN

the NNW-SSE trend of the orogen; and it is unlikely for such a major deflection from the trend of the main fold belt to be the result of orthogonal ENE transport meeting an obstacle at the end of the belt. It is entirely compatible with the NE-vergent transpressive hypothesis for the orogeny where there is no need for partitioning into compressive and transcurrent components. Elsewhere that appears to be necessary. A. McCann (pers. comm.) has described an eastward vergent N-S thrust fault separating the Red Bay Group strata from the Precambrian horst through the length of the BiskayerfonnaHoltedahlfonna terrane has been referred to (in Chapter 8) as a Devonian structure and is mapped as connecting to the north with a N W - S E fault beside Hornemanntoppen. There are no younger age constraints on this fault and it would also be consistent with the Paleogene stress regime. The fold belt north of Isfjorden appears much wider than to the south. The curvature of the Broggerhalvoya virgation was caused by the obstruction in the north of the main strike-slip component (hence thrusting) and in the east by the Nordfjorden Block (with thin-skinned thrusting). South of Isfjorden the transpression was partitioned into strike-slip faulting and ENE thrusting even beyond the Central Basin. A thorough structural study of a relatively simple segment of the orogen by Braathen, Bergh & Maher (1995) has already been referred to with evidence of a northerly as well as a westerly vergence in the thrust structures. Their interpretation of a structural sequence is illustrated in Fig. 20.10 with initial north-south shortening followed by eastwest shortening in turn followed by inversion, uplift and easterly verging rotation and then by collapse from a late extension. The above model fits a general conclusion that the initial transpression was an oblique dextral compression verging N N E and against the somewhat westward protruding terrane of northwest Spitsbergen. This movement would have accentuated the curvature of the structural area and blocked further northward thrusting. Thereafter the transpression would have been partitioned into ENE verging compressive and N N W strike-slip (transcurrent) faulting (Fig. 20.11).

BELLSUND

North-South shortening

STAGE 1 Initial shortening

..\ Initial East-West shortening

STAGE 2a

Pk

Initial inversion

STAGE 2b

Major inversion, uplift and rotation

STAGE 2c

~

KT

Late extension

STAGE 3

Major inversion

Uplift and erosion

~

~-Pk,

Late extension

HH Pk

Carboniferous extensional faults

=""

411

Paleogenefault movements

Fig. 20.10. Interpretation of the structural development of Paleogene structures in Nordenski61d Land (with permission after Braathen, Bergh & Maher 1995). See also Fig. 10.8.

K2

Paleocene Dan I Tha

Orvin 1940

Ypr

All Pg dp

Hadand 1961

up (dn)

Atkinson 1963

Tilt up to the N

}

Eocene Lut I Brt

//

cp

FSG Collapse of W coast horst

dp /dp

tp

Birkenmajer 1972

dp

Lowell 1972

dp

/tt

L

cp

Xtdptt tt

N~ttvedt 1988 Lyberis & Manby 1993

cp

up cp &dn extensional grabens

t

~

i

tp & Spitsbergen trough

tt

up

extension FSG

ext FSG etc tt (D6) / /tp

xt tt

I

North of Ist}orden only

tp (D5)

Craddock 1985

tp

tp WSO

--dp

Kellogg 1975

Steel et al. 1985

tp, up at,d dn t

tt CB1 & CB2 cp

and FSG

Zx/C0

-~

Major & Nagy 1972

Ng,

xt

I

Fig. 20.11. Historical review of Paleogene tectonic models for Svalbard, symbols as follows: cp, compression; dn, denudation; dp, deposition; xt, extension; tc, transcurrence (strike-slip); tp, transpression; tt, transtension; up, uplift; FSG, Forlandsundent Graben; WSO, West Spitsbergen Orogen.

Oligocene Rup I Cht

Prb

All cp folds precede faults

dp

Harland 1969, 1971

Hanisch 1984

I

I

tp

/tt

tp

xt xt

tt (FSG)

dp !

This work

Up toN

tctp

dp

I

ltpup (tc) tt L

(cp)

tc

dn

tc

412

CHAPTER 20

The ENE compression had its deep axis in the strike-slip shear zone (the root zone of the nappes) which changes eastwards from steeply W-dipping thrusts to thin-skinned (often bedding) thrust structures. These low angle thrusts and related folds slide over the Nordfjorden Block to the north mainly in Permian strata. To the centre

TIMESCALE Miocene 0 tO

Aquitanian (Aqt)

Ma 23.3-

GREENLAND GREENLANE SVALBARD

mOMALuLABRADOR 6

0

29.3-

38.6

Bartonian (Brt) 42.1

13 _15 16

17 19

36 Ma

~ !

i

A t?

~rj t--

22 23 24

60.5

26

65.0

27 28 29

o

Danian (Dan)

56 Ma

tp through WSO and E North Greenland and to S

59 Ma

tp off Hornsund tt Sorkapp to NW of Bj~rn~ya and tp S of Bj~rn~ya

30

Maastrichtian (Maa)

31

69 Ma

On Hornsund Fault Zone tc off N. Svalbard tt S. of Hornsund and tp W. of and to SE of Bj~rn~ya

80 Ma

Dextral tc on Troll Land Fault Zone tp to SE of Svalbard

32

0

CB6

I

CB5 CB4 CB3 CB2 CB1

PENEPLANATION

33

Campanian (Cmp)

Ir

o

0

!

74.0

0

._1 II LL .J

tc within WSO and E North Greenland tt SW of Bj~rnoya

WSO

25

Thanetian (Tha)

I

IL 49 Ma

56.5

E North Greenland, with spreading SW of Spitsbergen

UPLIFT

]

? "1

O

Ypresian (Ypr)

o o

tt through WSO and .,Q

Lutetian (Lut) 50.0

tO

._

~

18

o

o 0 ILl

i

12

35.4

Priabonian (Prb)

10

FSG

Rupelian (Rup)

to

SVALBARD

MOLLER & SPIELHAGEN 1990

o_~ ~O N ~ r

7

Chattian (Cht)

o 0 o~

0

and south, the Central Basin escaped much folding at the surface except along ancient fault zones. The bedding thrusts probably favoured Mesozoic shales beneath the overlying Cretaceous and Paleogene sandstones. Evidence for this is in the thrust structures that surface over the buried Billefjorden and Lomfjorden fault zones, and also elsewhere.

Tilt up to N

83.0" Santonian (San) Coniacian (Con) Turonian (Tur)

86.6 _ 88.51 - 90.4

Cenomanian (Cen) 97.0 o Q o in

o

34

Carolineflellet Fm

Albian (AIb)

LLI

ilro7. Fig. 20.12. Paleogene time-scale, with major magnetic anomalies. Regional tectonic events are indicated with reference to Svalbard (after Harland et al. 1990; Miiller & Spielhagen 1990). Key: WSO, West Spitsbergen Orogeny; FSG, Forlandsundet Graben; tp, transpression; tt, transtension; tc, transcurrence; CB1-6, Central Basin Paleogene formations.

PALEOGENE HISTORY

413

In Chapter 9 it was suggested that the seemingly west-verging fold and thrust structures in the Prins Karls Forland Horst were not Caledonian, but part of the same Paleogene West Spitsbergen Orogeny. If so then the 'flower structures' of Lowell (1972) may be a useful model. A schematic diagram of the structures in mid western Spitsbergen is drawn in Fig. 20.7 combining features from Nottvedt et al. (1988) and from Lowell (1972).

20.8

Regional tectonic sequence

The above structural conclusions were arrived at before, and then independently of, the ocean-spreading data that became available in the Arctic. Thereafter, the various palinspastic models could be related to oceanic magnetic anomalies and so in turn to the time scale. This was especially valuable in Svalbard tectonics because of the weakness of Tertiary stratigraphic correlations. The first, and remarkable impact in this way, was perhaps the reconstructions by Pitman & Talwani (1972) who, by extrapolating plate motions from North Atlantic data well to the south of our area of interest, showed a sequence of motions between Greenland and Svalbard (with the Barents-Baltic plate) in which successive positions between Greenland and Scandinavia with Svalbard were depicted (their fig. 7). From this, in their fig. 8, Spitsbergen progressed dextrally past eastern North Greenland and then plots a collision between them at about 47 Ma. Their anomalies were dated (in that exercise) consistently 3 or 4 million years younger than in the scale adopted here in Fig. 20.12. Consequently on that reckoning the maximum plate overlap would be nearer 51 Ma which is Late Ypresian here. In any case an Eocene orogen is consistent with their data. Many further plate tectonic studies have been made, not least by Srivastava & Roest (1989) whose data were adopted by Mtiller & Spielhagen (1990) in their study of late Cretaceous and Paleogene evolution of the Central Basin, as copied here in Fig. 20.13. A summary of the Paleogene palaeogeography of Svalbard is shown schematically in Figs 20.15 and 20.16 (a-c) to illustrate the largerscale kinematics during this time. These events are plotted against a time and anomaly scale in Fig. 20.12 in which the range of opinion as to the ages of the Paleogene strata CB1-CB6 is narrowed to be consistent with available evidence. Kinematic models for the Cenozoic evolution of the Greenland Sea area generally show a stepwise opening, with a northeasterly propagating rift axis (Eldholm et al. 1988). The plate configuration between anomalies 23 and 13 (54-36 Ma) gave rise to transpression between northeast Greenland and western Svalbard as rifting progressed, the resulting effect being the West Spitsbergen Orogeny, with maximum shortening and distributed transpression, from late Paleocene to early Eocene (Fig. 20.14). As separation of Greenland and Svalbard progressed, so the effects of transpression rapidly waned, such that by anomaly 21 (49.5 Ma) transpression was largely confined along the Senja Fracture Zone (Fig. 20.14a). The early Oligocene plate reorganisation in the North Atlantic at anomaly 13 (36 Ma), during which relative plate motion changed to northwest, gave rise to a predominantly tensional regime in the northern Greenland Sea area and along the western Svalbard and Barents Shelf margin, with extensional faults being active along the Hornsund Fault Zone (Fig. 20.14b). Other kinematic models along similar lines have been produced by Srivastava (1985), Jackson & Gunnarsson (1990), Lepvrier (1992), Kleinspehn & Teyssier (1993) and Teyssier, Tikoff & Manby (1995). The Eurekan Orogeny recorded extensively in Ellesmere Island, was the sinistral counterpart coeval with the dextral Spitsbergian Orogeny. However. the compressive component was more pronounced and instead of a simple sinistral shear zone along the postulated Wegener Fault of the Nares Strait, compressive fold structures are distributed rather generally so that the displacement was pervasive. This structure has been debated for many years, for example by De Paor et al. (1989).

b

Fig. 20.13. Sequence of maps showing the motion of Svalbard relative to Greenland (fixed) for latest Cretaceous to Oligocene time. Diagonal shading indicates overlap; bold dots indicate gaps (with kind permission of Elsevier Science, Amsterdam after Mtiller & Spielhagen 1990).

20.9 20.9.1

Paleogene tectono-sedimentary history Pre-Firkanten Formation events

There is a gap in the onshore record between the Albian Sch6nrockfjellet Member of the uppermost (Carolinefjellet) formation and the early Paleocene Firkanten Formation of the Paleogene Van Mijenfjorden Group. The gap is not less than 32 million years. In structure the hiatus is seen as an unconformity with overstep, but no overlap. As detailed in Section 19.7.6, the whole Nordenski61d Land Supergroup of Mesozoic strata is overstepped northward, with an average angular unconformity of 0034p, i.e. eroding about 2500m of strata in 250km from south Spitsbergen to Kongsfjorden. The tilting was attributed to thermal expansion of the mantle prior to the opening of the Eurasian Arctic Ocean Basin along the Nansen-Gakkel Ridge (Harland 1969a).

414

CHAPTER 20

\

. - -

@

"I ,

\

,% \ ~

I

SVALBARD

Q!

/

I 1

0~'ot~

r5o E

/, s S

BJORNOYA

~,s" s

SR

sS

II

S/

s S s s SS

TFP

70~

o

. ,~

~ .......

2~,12b~(

~-

.-

I

n

c.._

\

•o•s•~

(9

~A%~ ~

...,. "" ~ (~)

ooooooOOo~176176176

"f, oo~"

s

fAY

.__,

15~

0

L_.

]

200 km I

This fission probably began in earliest Paleocene time but the earliest ocean striping age is 5 3 M a (from Harland et al. 1990 timescale) between anomalies 25 and 24, and was the northern and final phase in the spreading of the Atlantic Ocean, through the Norwegian and Greenland basins. The effect of this was to institute or develop a dextral transform fault zone between Svalbard and northeastern Greenland. Thus the movement of Svalbard away from the previously adjacent Lomonosov Ridge to the north was accompanied by dextral strikeslip against Greenland and with a corresponding spreading in the Norwegian-Greenland Sea basins at the southern end of the fault zone. The contrary idea of a late Cretaceous-Early Paleocene orogeny with North Greenland pressing against Svalbard at this stage (e.g. Hanisch 1984; Lyberis & Manby 1992; Manby & Lyberis 1997) may be rejected on three grounds: (i)

a Late Cretaceous orogeny is inconsistent with the evidence of coeval slow tilting referred to above; (ii) the orogenic structures contain deformed Firkanten and younger formations; (iii) the plate tectonic evidence of Late Cretaceous compression in North Greenland was not necessarily opposite Spitsbergen at that time (Fig. 20.13a & b).

J

Fig. 20.14. Diagrammatic model for the Cenozoic sea-floor spreading, dextral strike-slip and transpression between Svalbard and Greenland for (a) Anomaly 23 (54 Ma) and (b) Anomaly 13 (36 Ma). Numbers in circles refer to fault zones: (1) Trolle Land Fault Zone; (2) Hornsund Fault Zone; (3) Senja Fault Zone; (4) Bj6rn6ya-S6rkapp Fault Zone; (5) Florlandsundet Graben; (6) Breibogen Fault Zone; (7) Billefjorden Fault Zone; (8) Lomfjorden Fault Zone. Letters refer to submarine features: HB, Hammerfest Basin; LH, Loppa High; SH, Stappen High; SR, Senja Ridge; TB, Troms6 Basin; TFP, Troms-Finnmark Platform. Numbers refer to anomalies, with shading indicating areas of transpression (adapted with permission from Eldholm, Faleide & Myhre 1987).

The model of spreading referred to here has been accepted by most other geoscientists. It was first suspected by Harland (1961) and Heezen (1961) and was formulated by Harland (1965, 1967) and has been amply confirmed by ocean spreading data not then available. Nevertheless the Kronprins Christian Land (dextral transpressive) Orogeny in eastern North Greenland has been argued as Late Cretaceous (H~kensson & Pedersen 1982; Pedersen 1997). The dextral transpressive deformation in that region began earlier. Greenland had begun to separate from Labrador at about Anomaly 33 (i.e. approximately at 80 Ma). That spreading of the Labrador Sea until about Anomaly 13 (c. 35Ma) spanned Santonian through Priabonian (Late Eocene) stages. Thus, from about 80 or even 90 M a to about 60 Ma Svalbard moved north together with Greenland, with little or no differential movement between them, and this corresponds approximately to the stratigraphic hiatus with gentle tilting of Svalbard prior to the fission. Lateral tectonic stress probably had little effect other than inducing some jointing. At first sight it might seem that the Paleogene dextral strike-slip zones were determined by the Silurian-Devonian sinistral strikeslip fault zones, seen onshore. But, the evidence supports the view that most of the onshore fault zones, although reactivated by compression or extension, did not take up the dextral motion which instead sliced through to the west of Spitsbergen. It seems probable

PALEOGENE HISTORY (Smith pers. comm., in press) that Bjernoya was attached to eastern North Greenland in Late Proterozoic through Paleozoic and Mesozoic time and did not move northwards with the other Svalbard terranes by sinistral strike-slip. But when the Paleogene dextral faulting developed, Bjornoya became separated from Greenland and moved south with Svalbard.

20.9.2

Mid-Paleocene events ( 6 3 - 5 7 Ma)

This interval refers to an indefinite time span to include Late Danian and Early Thanetian or Selandian for example 63 to 57 Ma (Fig. 20.15). Land to the north and east of the Central Basin was drained to a deltaic front advancing into a sea whose extent to the west has been obscured by later tectonism. The Central Basin following a Mesozoic platform sequence extended to the north so as to include the Ny-Alesund coalfield. These conditions prevailed with the deposition of CB1 and CB2 of this Central Basin (Firkanten and Basilika Formations) and the coeval Ny-Alesund Subgroup; possibly also the I~yrlandet strata. Signs of tectonic disturbance are observed in the Ny-Alesund Subgroup where the Tvillingvatnet Member (of the Kongsfjorden Formation) rests unconformably on truncated beds of the Kolhaugen Member.

BFZ

415

It is probable that Svalbard (with Eurasia) began to part from Greenland along a dextral strike-slip zone, at first with pure transcurrence, possibly with some transtension, so deepening the Central Basin and possibly initiating the Forlandsundet Graben to the west. A strike-slip zone could already have been operating just west of the Central Basin, without noticeable effect on sedimentation provided there was no significant transpression or transtension. The deepening of the Central Basin following CB1, with the basal conglomerates of the Firkanten Formation, exceeded sediment supply with the retreat of delta fronts and the largely argillaceous CB2 (Basilika) sedimentation.

20.9.3

Latest Paleocene-Eocene ( 5 8 - 3 8 Ma)

The strata from CB3 through CB6 record the filling of the basin and the new source of sedimentation in the west (Fig. 20.16a, b & c), corresponding to the initial uplift of the West Spitsbergen Orogen, thus yielding advancing delta deposits into the Central Basin. The earliest evidence of such disturbances could be latest Paleocene. The evidence for the main tectogenesis of the West Spitsbergen Orogeny is seen in the soft sediment slumping and deformation in CB3 to CB6. It has been argued that the main deformation was at least postFirkanten Formation from the classic work of Hoel & Orvin (1937) and Orvin (1934, 1940). Harland (1961) depicted a greatly extended orogenic belt within which the Forlandsundet Graben formed, probably at a late stage. In 1965 to 1969 the orogeny was argued to be the effect of oblique collision with Greenland as a result of dextral strike-slip. This transpression model for Paleogene history (a)

BFZ o

;.iP

":..:.

o

- ~

I

-l-xJ

_

m

m

_

_

_

% _--

---

H

_ .~.--..=_-

~

~

-

~ ~

? -z

Mid-Paleo

~

Land/ sourcea r e a

~

Deltafront/ shoreface

~

Proximalalluvium

~

Prodelta/ offshore

Deltaplain/ tidalfiats

Fig. 20.15. Palaeogeographic map of Spitsbergen in Mid-Paleocene time.

Deposition of upper Firkanten and Basilika formations. H, Hornsund Fault Zone; BF, Western Boundary Fault; BFZ, Billefjorden Fault Zone; LFZ, Lomfjorden Fault Zone (adapted with kind permission of Elsevier Science, Amsterdam from MiJller & Spielhagen 1990).

Latest Paleocene

\

"~

Fig. 20.16. Paleogene palaeogeographic maps of Spitsbergen. (a) Deposition of the Hollendardalen Member (Sarkofhgen Formation); (b) deposition of the middle Gilsonryggen Formation; (c) deposition of the upper Battfjellet and Aspelintoppen formations. For key refer to Fig. 20.16 (adapted with kind permission of Elsevier Science, Amsterdam from Miiller & Spielhagen 1990).

416

CHAPTER 20

(b) BFZ

:."i i '.1

Late Early Eocene

(c) BFZ

Early Mid-Eocene Fig. 20.16. (continued).

was developed i.a. by Lowell (1972) a n d in m o r e detail by Steel et al. (1985). The current view in this w o r k is that the initial g r a b e n was f o r m e d in the preceding interval. In plate tectonic terms this transcurrent-transpressive phase corresponds to the c o n c u r r e n c e of seafloor spreading in both the L a b r a d o r Sea and the Eurasia Basin a n d G r e e n l a n d - N o r w e g i a n seas. D u r i n g this phase the zone is a transform fault zone connecting the Eurasia Basin with the G r e e n l a n d - N o r w e g i a n Seas. M a g n e t i c a n o m a l y patterns are consistent with a very tight (transpressive) passage in Eocene time. The transpressive hypothesis is based on the fact that compressive structures were f o r m e d (often with E N E vergence) t h r o u g h o u t m u c h o f the length of the orogen, coinciding with a time o f d e m o n s t r a b l e dextral strike-slip. T h a t the main structures a p p e a r to be compressive is typical o f transpressive situations w h e r e partitioning of strain compensates c o m p r e s s i o n by transcurrence, i.e. strike-slip faulting. This is consistent with the c o n t e m p o r a r y d e v e l o p m e n t of parallel graben structures. H o w e v e r , the n o r t h Oscar II L a n d virgation, verging N to N E , fits a distinctive transpressive origin a n d is consistent with the hypothesis of dextral motion. Instances o f dextral strike-slip within the orogen have been referred to in C h a p t e r s 9 a n d 10. The processes that led to the visible Paleogene structures m a y be s u m m a r i z e d as follows. (a) Ocean stripes confirm the simplest hypothesis that Spitsbergen moved uniformly from its initial position, north of North Greenland, to its present position along dextral strike-slip fault zones. Thus two adjacent plates (Laurentia and Eurasia) were sliding against each o t h e r with northeastern Greenland and Spitsbergen almost in contact. (b) Following a transtensional phase (in which the Central Basin deepened and the Forlandsundet Graben developed), at or about 58 Ma the plates moved together and their adjoining margins transpressed. Transpression continued until about 37 Ma with a climax at about 45 Ma. (c) The visible result of this transpression was first overfolding and thrusting in Spitsbergen towards the NE or NNE in Breggerhalvoya. The structures in Breggerhalvoya conform to a dextral transpressive deformation (only) because the way to the north (of Kongsfjorden) was blocked. Subsequently the main dextral strike-slip displacement must have been in fault zones to the west because the strike-slip movements continued throughout. Therefore, in most of the orogen the strain would have been partitioned between the ENE thrust structures onshore and the strike-slip zone(s) offshore. It is no argument against transpression to say that the strike-slip zones do not exist because they very likely could not be seen beneath sediments offshore. There are, however, several pieces of strike-slip structure even on land (in Chapters 9 and 10) and especially the Kaffieyra shear zone of Ohta et al. (1995). However, they are not necessary to this argument. The actual structures have been outlined in the foregoing section. They dip westwards towards a possible root zone and extend eastwards often with thin-skinned deformation and as part of an extensive decollement. (d) The root zone could lie in the Forlandsundet Graben if, as is suggested here, the WSW verging folds and thrusts in northern Prins Karls Forland are on the other side of the root zone. (e) Mineralization. It has already been noted that metallic sulphide occurences are almost entirely limited to the western province and this has been correlated with a probable origin within a north Greenland-Ellesmere Island-type basement. It may also be generalized that the minerals occur mainly in carbonates and associated with fault breccias. It so happens that this whole terrane lies within the West Spitsbergen Orogen so that the genesis may well be Proterozoic, Paleozoic or Paleogene and it could have resulted in more than one event. The simplest hypothesis, and the author's preference, is to follow Hjelle (1962), that all occurrences may be from Proterozoic basement rejuvenated in Paleogene time because there may not have been another extensive orogenic suture since Proterozoic time. An alternative route from depth could be via the Silurian-Devonian sinistral fault zones to the east, within or to the west of the observed basement. The Eidembreen Ordovician event while bringing up blueschist facies from depth does not appear to be mineralised in this way. This might support the earlier suggestion that the Vestg6tabreen Complex is metamorphosed subducted Vendian strata and that the source of metals is pre-Vendian. Further speculation is not profitable without some geochemical survey of the problem.

PALEOGENE HISTORY

20.9.4

?Late Eocene-Oligocene events (c. 35-23 Ma)

With the stabilization of the Labrador Sea, Greenland again became fixed to Laurentia and the continued seafloor spreading in the Eurasia Basin and on the Greenland-Norwegian Sea was accompanied by transtension in the linking transform fault, so joining these ocean basins by a connecting strip of expanding ocean. In particular, the Yermak Plateau submarine eruptions may belong to the earlier part of this interval. This development with transtension may have allowed the later stages of sedimentation in the graben. But the principal beneficiary of sedimentation was the offshore shelf and the newly formed ocean floor west of Svalbard, so receiving debris from the erosion of the uplifting orogen. This story, with the complex pattern of submarine faulting, basins and highs, continuing to the present day, is followed in the next chapter (21).

20.9.5

Plate-tectonic sequence

The foregoing history of events in Svalbard fits neatly into the plate-tectonic sequence that is now well established through ocean stripe studies. Before this precision was available the first model of dextral strike-slip translated Spitsbergen from a position north of North Greenland to its currently mobile situation. This sequence was first related to Spitsbergen sedimentation and tectonics in 1964 (Harland 1965) and amplified somewhat in 1966, 1967 and 1969 showing the West Spitsbergen Orogen to be the result of a glancing collision with eastern North Greenland at about Eocene time. The earliest ocean stripe projection to this area was from data far south in the North Atlantic Ocean by Pitman & Talwani (1972) and it almost exceeded what was required with a significant overlap of Greenland and Spitsbergen at that time. This was good confirmation, if confirmation were needed, of the age of the West Spitsbergen Orogeny. M a n y further refinements in the sequence of plate motions followed, e.g. Talwani & Eldholm (1977), Srivastava & Tapscott (1986), Srivastava & Roest (1989). Mfiller & Spielhagen (1990) made a convenient synthesis of the 1989 reconstruction with the Spitsbergen tectonostratigraphic story which is followed and illustrated in Fig. 20.13 (from their figs 3 and 6). 'For the time between chrons 33 and 25 the resulting differential motion is by right-lateral strike-slip. The plate boundary was most probably located in northeast Greenland at the Troll Land fault system as a continuation of the Senja fracture zone [then] the plate boundary jumped eastward to the Hornsund Fault Zone. A drastic counter clockwise change in spreading direction in the Labrador Sea between chrons 25 (59 Ma) and 24 (56 Ma) caused transpression between Greenland and Svalbard, resulting in about 50-70 km shortening and a 30 km strike-slip motion. Strike-slip dominated transpression characterised the period from chron 24 to 21 giving rise to 160km of dextral strike-slip and 15-20 km of shortening. The relative motion between Greenland and Svalbard was dominated by strike-slip until chron 13 (36Ma) subsequently followed by transtension, after seafloor spreading in the Labrador Sea had ceased.' (from Mfiller & Spielhagen 1990, caption to their fig. 6, p. 162).

417

Within this overall kinematic sequence, which he did not question, Lepvrier (e.g. 1992) from local structural studies proposed two phases in the dextral transpressive tectonism on dynamic grounds. In phase 1 the maximum horizontal stress al was oriented 10-20~ i.e. at about 45 ~ to the transform trend and so by 'coupled' transpression generated the NW-trending folds and thrusts verging NNE. Phase 2 followed, with a: oriented 70-80 ~ i.e. E N E producing the N N W fold and thrust belt in which case the transpression was 'decoupled' so that the conspicuous compressive component was allied to an inconspicuous (yet in places evident) strike-slip component. It may be recalled that the concept of decoupling or partitioning components was explicit in the original formulation of transpression (Harland 1971) and has been affirmed many times (e.g. Faleide e t al. 1988; Haremo & Andresen 1988; Maher & Craddock 1988). Lepvrier (1992) further suggested a net dextral strike-slip of 550 km in the first 20-25 million years of Svalbard's translation past North Greenland. This contrast in part accounts for the different structural styles north and south of Isfjorden and even for the Isfjorden Fault separating them. As pointed out by Wennberg, Hansen & Andresen (1992) the changing stress and strain orientations need not require changing directions of plate motion when curvatures in the plate boundaries might account for changes between transpression and transtension as was illustrated by Harland (1971). Pedersen (1988) referred to three structural events in the late Mesozoic platform break-up between Greenland and Svalbard (i.e. in the Wandel Sea strike-slip Mobile Belt): (1) the extensional, Ingeborg Event with Jurassic listric normal faults; (2) the transtensional, Kilen Event; (3) the main compressional-transpressional tectonism of the Kron Prins Christian Land. Strike-slip Orogeny (striking NW-SE), accompanied by structural inversion of the basins with three structural phases: (i) transpressional shear with anastomosing joints; (ii) en ~chelon dome folding with thrusts which are cut by (iii) dextral strike-slip faults. This event is dated 'Late Cretaceousearliest Tertiary time'. A late Paleocene-Eocene age correlating with the West Spitsbergen and Eurekan orogenies was favoured by Soper et al. (1982), whereas a Late Cretaceous age as favoured by Hgtkensson & Pedersen (1982). H~kensson (1988) admitted the uncertainty of the evidence supporting these two views while favouring the second. Correlation with the West Spitsbergen Orogeny would be convenient, but not necessary (for which a Cretaceous age has been advanced and rejected). Three 'pronounced lineaments' regarded as fundamental faults were mentioned in the northeast corner of Greenland by Pedersen et al. (1992): Harderfjord Fault Zone (E-W, HFFZ), East Greenland Fault zone (N-S, EGFZ) of ancient origin and the post Ellesmerian Trolle Land Fault system (NW-SE, TLFS) of the Kron Prins Christian Land Orogen. A further arcuate thrust fault (Kap Cannon Thrust zone) with e. NW-SE compression would be consistent with the dextral TLFS. In conclusion, whereas Paleozoic sinistral fault zones and the Cenozoic dextral fault zones migrate and do not necessarily coincide, the net effect is a reversal of the motion of the main body of Svalbard. The sinistral collision zone became the Lomonosov Orogen. It became a ridge when northern Svalbard was separated from it dextrally by the N a n s e n - G a k k e l fission and spreading, a likely consequence of the heat accumulating in the thickened continental crust.

Chapter 21 Neogene-Quaternary history W. B R I A N H A R L A N D

with contributions by C L A R E

F. S T E P H E N S

Glacial history of Svalbard: Neogene-Holocene, 429

21.1 21.2 21.2.1 21.2.2 21.2.3 21.2.4 21.3 21.4 21.4.1 21.4.2 21.5 21.5.1

Neogene-Quaternary time-scale, 418 Plate motions (C.F.S.), 418

21.7 21.7.1

Anomaly 25 to 13 time, 418 Anomaly 13 time, 421 Post-Anomaly 13 time, 421 Present-day spreading, heatflow and seismicity, 421

21.7.2 21.7.3 21.7.4 21.7.5

Deep structure of Svalbard, 421 Neogene-Holocene volcanism and thermal springs (C.F.S.), 423

21.8

Eruptive centres, 423 Fluid springs and seepages, 424

21.6

Neogene-Holocene uplift and erosion, 427

21.8.1 Glaciofluvial-fluvial sediments, 432 21.8.2 Alluvial fans, talus cones and rock glaciers, 432 21.8.3 Raised-beach morphology, 432 21.8.4 Permafrost and patterned ground, 432 21.8.5 Freeze-thaw processes, 433 Post-glacial sea-level changes, 434 21.9

Neogene-Pleistocene marine sedimentation (W.B.H. & C.F.S.), 426

Moffen, 427

21.6.1 Neogene shaping of Svalbard, 428 21.6.2 Quaternary development of land-forms, 429

This is the final historical chapter in this work outlining principal post-Paleogene events. Section 21.1 summarizes the time scale for these events. The evidence for this is mostly in the interpretation of geomorphic features of uplift and denudation with little preservation of onshore sediments until after the main glaciation had ceased its erosive activity. The consequential depositional record is thus mainly submarine until Holocene time, when it could relate to onshore history. Figure 21.1 shows the distribution of Neogene and Quaternary volcanics, hydrothermal zones and areas of recent seismic activity. Many geoscientists are preoccupied with the closing stages of this story and another volume this size might be needed to do justice to Quaternary studies in Svalbard. This chapter brings geologic history to the present, whereas Chapter 22 is concerned with observable processes whose time scale is that of the scientists themselves and thus moves from geological to geoscientific time. To the adage that we interpret the past from the present it is equally true that we interpret the present from the past. Indeed, this is the essence of the historical enterprise that has motivated this work

21.1

Neogene-Quaternary

time scale

This geo-historical chapter spans a time interval through to the present, with the consequence that human perspective coupled with a record of events increasingly available has led to successively shorter time divisions to accommodate the data. There has been a corresponding muddle over conventional divisions. Here (for consistency in this work) the classification is adopted from Harland et al. (1990) where its history and rationale was discussed (Fig. 21.2). Indeed, some detail there is hardly applicable in Svalbard; but the objective of international correlation, especially of submarine deposits remains. Currently the successive magnetic anomaly values are in use. Each numbered anomaly ideally is in two parts. The older being a reversed magnetic polarity and the younger being of normal, present day, polarity. However, many anomaly numbers span several reversed and normal episodes and the normal events may be referred to as chrons. These are not detailed here but may be found with some discussion in Harland et al. (1990) and more specifically in Myre et al. (1995, p. 32). The main problem for the later part of the Pleistocene Epoch is that glaciation has removed most of the record on land until the latest retreats. Many of the Holocene events can be correlated stratigraphically, as by volcanic pumice in raised beach deposits, and the later sequence of biotas reflects climatic fluctuations rather than evolutionary progress.

21.2

Glacial episodes, 429 Moraines, 431 Submarine glacier-fed sedimentation, 431 Submarine glacial plowmarks, 431 Uplift and subsidence in relation to glaciation, 431 Pleistocene and Holocene surficial geology and geomorphic features, 431

Plate motions

The Neogene-Pleistocene plate motions that directly affected the tectonic, geological and geomorphic development of Svalbard are considered with their broader context in terms of the overall evolution of the area, both spatially and temporally. Therefore, this section encompasses the plate motions from the time of opening of the Norwegian Sea to the present, and spreading throughout the Norwegian-Greenland Sea and the Eurasia Basin (Fig. 21.3).

21.2.1

Anomaly 25 to 13 time

The Norwegian-Greenland Sea opened between anomalies 25 and 24 (Talwani & Eldholm 1977) (that is c. 53Ma according to Harland et al. 1990); Greenland moved northwest relative to Eurasia. Active sea-floor spreading was also initiated in the Eurasia Basin at this time and has since been confined between the Lomonsov Ridge and the Barents Sea shelf (Eldholm et al. 1984; Srivastava & Tapscott 1986; Kristofferson 1990). The subsequent motion between Greenland and Svalbard was dextral strike-slip along the NNW-SSE-trending Hornsund Fault Zone. Plate tectonic reconstructions prior to Anomaly 13 show an overlap between Greenland and Svalbard which results from strike-slip motion until Anomaly 13 (Srivastava & Tapscott). During anomalies 24 to 21 time simultaneous spreading occurred all round Greenland (Srivastava & Tapscott) including spreading in the Labrador Sea linked to the Mid Atlantic Ridge at an active triple junction at the southern end of the Labrador Sea (Nunns 1982). The change in direction of motion between Greenland and North America at Anomaly 24 time, associated with the opening of the Norwegian Greenland Sea, resulted in the Labrador Sea spreading obliquely to the ridge axis (Roots & Srivastava 1984). A quiet magnetic zone in the centre of the Labrador Sea is interpreted by Roots and Srivastava as the result of spreading between margins that were highly oblique to the spreading direction. Spreading in the Labrador Sea slowed significantly after Anomaly 21 (Nunns 1982; Srivastava & Tapscott 1986) and had ceased by Anomaly 13. The initial direction of spreading between Greenland and Eurasia was NW-SE, parallel to the transform faults bounding the Norway Basin (Nunns 1982). As a consequence of spreading slowing considerably in the Labrador Sea, the spreading direction in the NE Atlantic began to change towards an east-west spreading orientation. The new spreading was not parallel to the transform faults within the Norway basin and resulted in compression across

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420

CHAPTER

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NEOGENE AND QUATERNARY HISTORY the transform fault linking the Reykjanes and Aegir ridges (Nunns 1982, 1983; Srivastava & Tapscott 1986). Extensive volcanics offshore on the Arctic mid-ocean ridge in early Eocene time (anomaly 21) formed the Morris Jessup Plateau and the northern end of the Yermak Plateau by Oligocene time (Anomaly 13) (Feden, Vogt & Fleming 1979; Kristofferson 1990).

21.2.2

Anomaly 13 time

During Anomaly 13 time (36-34.4Ma according to Harland et al. 1990) there was a change in plate motions (Fig. 20.14). This was a consequence of the cessation of spreading in the Labrador Sea prior to Anomaly 13 time, c. 36 Ma (Eldholm et al. 1990), and a change in the pole of rotation resulting from the reorganisation of the North Atlantic from a three to a two-plate geometry (Kristofferson & Talwani 1977; Srivastava 1978). Greenland then moved with a westerly motion relative to Eurasia as part of the North American plate, consequently the strike-slip motion between Svalbard and Greenland changed to spreading and the Greenland Sea began to open (Talwani & Eldholm 1977; Srivastava & Tapscott 1986).

21.2.3

Post-Anomaly 13 time

Since Anomaly 13 there has been spreading along the whole of the plate boundary between Greenland and Svalbard. However, when the change in relative plate motion took place, the spreading axis in the Norway Basin continued to propagate north which resulted in a piece of the Svalbard margin splitting off. This is now named the Hovgaard Fracture Zone (Myhre e t al. 1982). The change in regional stress regime also resulted in the propagation of a rift northwards from the Reykjanes axis along the line of the Kolbeinsey axis which detached the Jan Mayen block from Greenland (Nunns 1982). Spreading continued on both the west and east of the Jan Mayen block, producing fan shaped magnetic anomalies until the Jan Mayen block had rotated away from Greenland enough to allow free spreading in the new direction along the Kolbeinsey Ridge in Anomaly 7 time (late Oligocene) (Nunns 1982, 1983; Srivastava & Tapscott 1986). From Anomaly 7 time spreading in the Norway Basin ceased and all of the spreading was located on the Kolbeinsey axis (Talwani & Eldholm 1977). The present asymmetric position of the Knipovich Ridge results from the latest eastward shift of the ridge in early Pliocene time (5-6 Ma ago) (Sundvor & Eldholm 1979). The rates of spreading gradually decreased from the time of opening of the Norwegian-Greenland Sea to Anomaly 7 time (late Oligocene), since then the rate has been variable (Talwani & Eldholm 1977). There was a reorganization of spreading rates along the central Atlantic spreading centre at 2.5 Ma (Klitgord & Schouten 1986). Talwani & Eldholm (1977) proposed that both the initiation and shifting of spreading axes apparent over time in the NorwegianGreenland Sea were associated with an abnormally elevated sea floor, generated subsequent to these events and possibly created when the spreading axis was situated over a large hot spot.

21.2.4

Present-day spreading, heatflow and seismicity

Present-day spreading is centred on the Nansen-Gakkel Ridge in the Eurasian Basin, the Knipovich Ridge in the Greenland Sea and successively further to the south along the Mohns and Kolbeinsey ridges, Iceland and the Reykjanes Ridge (Fig. 21.4). Principal fault zones, structural highs and basins on the Barents Shelf in addition to the modern physiography of the western Barents Sea are detailed in Fig. 3.6.

421

Northern Svalbard and Nordaustlandet have a higher heat flow than the surrounding margins. This is related to the northwards propagation of the Mohns Ridge into the palaeo-Senja shear zone at a time when it was a transtensional margin (it currently delineates the southwestern margin of the Barents Shelf), creating the Barents Asthenospheric Corridor (Okay 1994). Northeastward propagation of this is interpreted as the cause of multiple basalt intrusions in Nordaustlandet. The major areas of seismicity in the region are located along the Knipovich Ridge and the Spitsbergen Fracture Zone, in the Heer Land/western Storfjorden area and on Nordaustlandet (Horsfield & Maton 1970; Austegard 1976; Mitchell & Chan 1978; Chan & Mitchell 1985b; Mitchell et al. 1990) (Fig. 21.1). Earthquake depths are typically less than 43 km (Austegard). The seismicity at both the Knipovich Ridge and the Spitsbergen Fracture Zone is of high magnitude and related to plate tectonic interactions. In contrast, the Heer Land/west Storfjorden area and Nordaustlandet typically experienced much smaller events which are concentrated on minor faults (Mitchell e t al. 1990), their maximum principal stress axes from fault plane solutions are oriented E-W. In Nordaustlandet two groups of earthquakes are found in NNW-SSE-trending patterns with the minimum principal stress axis oriented N-S: the pattern is similar to the major mapped faults in the area, although Mitchell et al. found difficulty in associating the earthquakes to specific faults. The orientation of the minimum principal stress axis is also found to be N-S in the Heer Land/ western Storfjorden area although in this case the seismic activity forms a N E - S W linear trend which is perpendicular to to the orientation of major locally mapped faults (Austegard 1976; Mitchell e t al. 1990). The consistency of the maximum principal shear stress was recognized and interpreted by Mitchell e t al. to indicate a single mechanism for the seismicity and that it was related to plate tectonic forces. Specifically they attributed the E-W orientation of the maximum principal stress axis to ridge-pushing forces (Solomon e t al. 1975; Richardson e t al. 1979) producing compressive stresses perpendicular to the ridge at distances of 200-300 km from the ridge axis.

21.3

Deep structure of Svalbard

A knowledge of the deep structure depends on deep wells or on surveys of geophysical parameters. In these respects Svalbard is marginal to the Barents Sea floor where such methods provide the main body of information which is outside the scope of this work. Moreover, such data are quite distinctive from palaeomagnetic studies which record history; the common geophysical fields surveyed (seismic, magnetic, gravity, electrical) record only the present structure of the Earth, a consideration that belongs to the last few years.

Seismic stratigraphy, however, in combination with other data extends stratigraphic and structural knowledge offshore. In this respect perhaps the University of Bergen has been notably active. A few of the key papers are listed here without further discussion. Austergard et al. (1988); Baturin (1988); Bro et al. (1991); Crane et al. (1982, 1988, 1990); Eiken (1983, 1985, 1993); Eiken & Austergard (1987, 1989); Einarsson (1986); Eldholm et al. (1984, 1987, 1988, 1990); Faleide et al. (1984, 1988, 1991); Feden et al. (1979); GECO (1977-1986); Gorski (1990); Guterch et al. (1978); IKU (1986); Kalsbeek et al. (1993); Kurinin (1965); Malovitskiy & Matirossyan (1995); Sellevoll (1982); Sellevoll et al. (1991); Solheim & Andersen (1995); Solheim et al. (1991); Sundvor & Eldhohn (1979); Sundvor et al. (1977, 1978, 1979, 1982, 1990); Sykes (1965); Vogt et al. (1978, 1982, 1990). The above are distinct from natural seismological activity already mentioned above (Section 21.2.4), work mainly led by Mitchell.

422

CHAPTER 21

Fig. 21.4. Present-day bathymetric structures in the North Atlantic (with permission after Dowling 1988, fig. 1, based on Talwani & Eldholm 1977).

Aeromagnetic survey. It was clear, after a proton magnetometer survey of Isfjorden from a C.S.E. motor-boat in 1962, that at sea level the noise from local dykes dominated any gradients that would identify major structural features. Magnetic profiling was reported by Am (1975). Skilbrei (1992b) reported aeromagnetic data from Spitsbergen with implications for the structure of the basement. The survey yielded a contoured residual aeromagnetic map of Spitsbergen south of a line from Krossfjorden to northern Storfjorden and including Prins Karls Forland. Without conspicuous lineation there are highs east and north of Ekmanfjorden, north of Billefjorden and north of Longyearbyen and several down eastern Spitsbergen

to Sorkapp Land, and with an irregular pattern of highs along the western coast of Spitsbergen. The pre-Devonian basement is generally sufficiently magnetic to identify its major features. Figure 21.5 combines Skilbrei's diagrammatic structural conclusion (1992b, fig. 8), with the coastline taken from his fig. 7. He commented on various highs marked H 1 to H8 and added to Fig. 21.5 and concluded as follows. The depth estimate to the base of the Devonian strata to the south and west of the Billefjorden Fault Zone at about 8km confirms the seismic result of Faleide et al. (1991) identifying the BFZ as its eastern margin in Isfjorden. The BFZ is clearly delineated not only where the pre-Carboniferous strata are exposed

NEOGENE AND QUATERNARY HISTORY 21.4

21.4.1

Fig. 21.5. Map showing depth to basement in Spitsbergen as defined from aeromagnetic data. BFZ, Billefjorden Fault Zone; LFZ, Lomfjorden Fault Zone (adapted with kind permission of Elsevier Science, Amsterdam from Skilbrei 1992b). to the north, but also to the south beneath the cover rocks and then out to sea. He noted that to the north, magnetic highs adjoin it on the east, whereas offshore to the south there are alternative interpretations: (i) that the projection of the BFZ lineament is more westerly and so still bounds high anomalies to the east as adopted here from Mann & Townsend (1988) or (ii) that a more easterly course merges with the Lomfjorden Fault Zone (LFZ) and so bounds the high anomalies to the west. The LFZ has no known history of early strike-slip. The first option is preferred here. Moreover, the (westerly) BFZ delineates approximately the Paleogene Central Basin. In either case a distinct horst in the basement is indicated offshore and in line with the fault zones. Offshore east of the Lomfjorden Fault Zone, the map indicates a depth of more than 9 km (anomaly H7) to the basement, so indicating thick cover sediments in the Storfjorden Basin. The two Edgeoya wells to the north also indicate, on the interpretation of this work, a notable thickness of cover rocks above the basement. The exposed basement along the west coast is clearly marked by magnetic highs as conversely are the local basins marked by lows. Similarly exposed basement in Ny Friesland is consistent with reconnaissance flights.

Gravity surveys.

Ground-based gravity surveys carried out in 1962 in Isfjorden (led by F. J. Vine) and later in Wijdefjorden (Harland et al. 1974), except for Forlandsundet, hardly discriminated the targeted structures, but together with the density determinations (Howells 1967; Howells, Masson-Smith & Maton 1977) may be reinterpreted in relation to the new magnetic survey of the basement.

423

N e o g e n e - H o l o c e n e volcanism and thermal springs

Eruptive eentres

Throughout Neogene and to Recent time, magmatism in the North Atlantic and Arctic areas has been focused at the spreading ridges detailed in the previous section. During this time there has also been continental basic volcanism in Svalbard. This section discusses the relationships between the different volcanic episodes on Svalbard which are distinct in both spatial and temporal terms. Detailed field decriptions of particular localities on Svalbard of the Neogene to recent volcanism are found in Chapters 7 and 8 and Fig. 21.1. This basic volcanism can be divided into two distinct groups: Miocene plateau lavas (the main exposures of which are on Spitsbergen) and Pleistocene volcanics in association with hydrothermal activity (Fig. 21.1). Prestvik (1978) dated the plateau basalts using K-Ar at 10-12 Ma (mid- to Late Miocene). The time span between the Neogene and Pleistocene events was approximately 10 million years (Tuchschmid & Spillman 1992). The eruptive centres of both the Neogene plateau basalts and the Quaternary volcanic centres (Hoel & Holtedahl 1911; Gjelsvik, 1963) are localized on N-S faults (Skjelkv~le et al. 1989). The volcanism may be related to the opening of both the Arctic Basin and the Greenland Sea (Vogt et al. 1978; Feden et al. 1979) and the anomalously high heat flow on the Yermak Plateau (Crane et al. 1982). As a result of geomagnetic and bathymetric data, Feden et al. suggested that the Neogene volcanic activity on Svalbard may have been associated with a regeneration of the Yermak Hot Spot and the resulting increase in magmatic activity on the Yermak Plateau around 10 Ma ago. Amundsen et al. (1987) concluded that the crust in the Bockfjorden area is approximately 27km thick. In addition they found the xenolith-defined geotherm to be high for northwestern Spitsbergen. They proposed that the high ambient temperatures probably reflect the addition of heat by basaltic magmas to the base of a continental crust thinned by rifting only 10-15 Ma ago.

Plateau lavas. The Neogene plateau lavas erupted onto a peneplain. There are two principal areas of occurrence: northwest Spitsbergen, mainly Andr~e Land and Ny Friesland. They are the Seidfjellet (lava) Formation (previously Sorlifjellet). Northwest Spitsbergen. Tuschmid & Spillman (1992) examined samples from the basalt flows in the Woodfjorden area at Risefjella (Fig. 21.1). The results showed there to be two lava types that were slightly differentiated: enriched olivine tholeiites and olivine basalts. The dominant phenocryst assemblage of both types of lava of olivine and plagioclase was interpreted by Tuschmid & SpiUman (1992) to reflect a crystallization depth of <15 km. They also inferred from the petrological data that the melts underwent crystallization and mixing in upper crustal magma chambers. The occurrences are plotted on the map (Fig. 21.1) Ny Friesland. An unaltered basalt exposed on the top of a nunatak in the upper part of the Manbreen Glacier in Ny Friesland is important in assessing the original areal extent of these plateau lavas on Svalbard. The following data are taken from Teben'kov & Sirotkin (1990). The lower part of the basalt is dense and light grey in colour. The upper part which is a maximum of 1.5 m thick is vesicular, scoriaceous, dark grey and black in colour with convex spheroidal joints. The modal composition of the basalt is: olivine (Fo6s) 5-10% clinopyroxene 30-40% plagioclase (An40-Ansa) 50-60% opaque minerals 5-10% iddingsite 1% glass 1-3%

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CHAPTER 21

Fig. 21.6. Map of the Bockfjorden area indicating the locations of hydrothermal springs and the Sverrefjellet volcanic cone. The TiO2 K20 P205 ratios (TIO2=52.6 54.5%, K20=37.0-38.6%, P205=8.3-8.8%) indicate that the basalt is non-oceanic (Teben'kov & Sirotkin 1990, using the scheme of Pearce et al. 1975). Its geochemical composition indicates that it is non-oceanic, different from both Mesozoic dolerites and Quaternary trachybasalts of Sverrefjellet (Fig. 21.6) (Kovaleva & Burov 1976). More importantly, it is similar in composition to the Miocene plateau basalts (Prestvik 1978) in Andr6eland (Teben'kov & Sirotkin 1990) (Fig. 21.7) which suggests a common magmatic source. If these two areas were originally linked then the Neogene basalt province extends further to the east than previously thought.

Central vent eruptions. Bockfjorden area. The timing of the construction of Sverrefjellet volcano in Bockfjorden was prior to, or during, the onset of the last major glaciation in Bockfjorden (SkjelkvAle et al. 1989) by palaeomagnetic data (Halvorsen 1972) and the occurrence of glacial erratics on the summit of the volcano (Skjelkv{de et al. 1989). There are geological features that imply the interaction of magma with active glaciers. There are three volcanic centres south of Bockfjorden: Sverrefjellet, Halvdanpiggen and Sigurdfjellet (see Chapter 8). Isotopic analyses show that the magmas are close to the nepheline basanite/nepheline hawaiite compositional boundary (Skjelkvfile et al. 1989). The Mg numbers (100 Mg/ [Mg + FEZ+]) and Ni are high which indicates that the magmas are primitive and some may be primary (SkjelkvAle et al. 1989). Semevskiy (1970a) had estimated the age of the Sverrefjellet cone to range from 6500 to 4000 years on the basis of terrace surfaces in the Bockfjorden area. The presence of abundant xenoliths indicates rapid ascent after entrainment of xenoliths from which Skjelkvgde et al. (1989) inferred that there were no crustal magma chambers but magmas rising directly from mantle depths. Tuschmid & Spillman (1992) examined examples from Sverrefjellet, Halvdanpiggen and Sugurdfjellet. The phenocryst assemblages of these rocks were dominated by olivine and titanaugite. This chemistry combined with the presence of abundant xenoliths (Amundsen et al. 1987) also led Tuschmid & Spillman to believe

Fig. 21.7. Compositions of Neogene plateau lavas, reproduced with permission from Teben'kov & Sirotkin (1900, fig. 2).

that these resulted from a rapid ascent from the upper mantle from depths c. 50 km. Western Barents Shelf margin. In addition to these eruptive centres on the archipelago there is evidence for basaltic volcanism on the western Barents Shelf margin in Late Pliocene time. Volcanic debris beds are found in Well 7316/03-U-01 within the upper part of a wedge of Miocene Pliocene sediments. The beds are predominantly composed of poorly sorted mixtures of ash and lapilli of basaltic composition they resulted from the rapid remobilisation and transport of volcanics and sediments by both high density (turbidity) currents and debris flows shortly after eruption through the sediments (Mork & Duncan 1993). The eruption site was proposed to have been located to the continental side of the continent-oceanic transition zone, between the Stappen High and the site of the core. The melts were generated at shallow depths (about 30 km) and rose through continental lithosphere resulting in mainly subaquatic eruptions, with some subaerial phases.

21.4.2

Fluid springs and seepages

This section describes the observed occurrences of springs in Svalbard. These are springs that are not connected either with water emerging normally from under large glaciers or from pingo mounds. In the Bockfjorden area hot springs penetrate the permafrost and reach temperatures of 28~ (V~gnes & Amundsen 1993), there are also similar springs and permanent holes in the

NEOGENE A N D Q U A T E R N A R Y HISTORY p e r m a f r o s t with g r o u n d t e m p e r a t u r e s u p to l l ~ scattered t h r o u g h o u t w e s t e r n S p i t s b e r g e n (Hoel & H o l t e d a h l 1911; Liestol 1977; M i g a l a & S o b i k 1982; Salvigsen & E l g e r s m a 1985). T h e l o c a t i o n s o f springs are s h o w n in Fig. 21.1 by n u m b e r listed below, this m a p a n d the following brief descriptions h a v e been principally c o m p i l e d f r o m H o e l & H o l t e d a h l , Liestol a n d M i g a l a & Sobik. T h e B o c k f j o r d e n a n d R a u d f j e l l e t springs in a d d i t i o n to the feature at T e m p e l f j o r d e n are discussed after these brief descriptions. (1) Jotun springs, Bockfjorden: two springs forming pyramid-shaped travertine deposits (Hoel & Holtedahl 1911). (2) Troll springs, Bockfjorden: six springs positioned along a N-Soriented line, these have formed large pools (Hoel & Holtedahl 1911). (3) On the north side of Kvadehuken situated on the west coast of Kongsfjordneset a large spring feeds a stream with a discharge (in May 1975) of 101 s-l; the water temperature was 1.7~ and air temperature was - 6 ~ (Liestol 1977). (4) To the south of Ny-.&lesund at the foot of Zeppelinfjellet a small lake (Tvillingvatnet) is fed by a spring in the bottom of the lake (Liestol 1977). (5) In front of Midre Lov6nbreen on the west side of Kongsfjorden there is a spring with a high salt content. In winter the water freezes to form large ice sheets all the way to the coast 1.5 km away (Liestol 1977). (6) and (7) On the strandflat north of Isfjorden large icings are observed in winter from the sea and on aerial photos (6), one particularly large one is located just to the west of Alkhornet (7) (Liestol 1977). (8) In inner Tempelfjorden a circular hole in the winter fjord ice has been noted on a number of occasions (Hoel & Holtedahl 1911). (9) There are at least three springs in the area between Linn6vatnet and Kongressvatnet south of Isfjorden (Liestol 1977). (10) At Finneset, on the east side of Gronfjorden, there is a small spring, the water temperature is 5.5~ and the discharge is 0.171s -1, in addition gas (mainly methane) bubbled up through the water (Liestol 1977). (11) Along the hilltop between Kapp Linn6 and Bellsund there are springs similar to those on the strandttat north of Isfjorden (6), one on the north side of Orustdalen produces a particularly large ice sheet (Orvin 1944; Liestol 1977). (12) On the Nordenski61d Land Winter Travel Map the ice at this location is described as being broken up as a result of escaping gas. (13) Raudfjellet region (Migala & Sobik 1982). (14) Springs are found at Sofiekammen on the north side of Hornsund, water temperatures were estimated at 10-12~ (Orvin 1944; Liestol 1977). (15) There were two springs recorded at the base of Tsjebysjovfjellet on the south side of Hornsund, the water temperature was estimated at 10-12~ (Orvin 1944; Liestol 1977). (16) Mohnbukta: spring with gas. (17) Mistakodden (Changing Point): 'Broxburn smell' was recorded. (18) Fugelhall: oily nodules found.

Raudfjeilet region, Wedel Jarlsberg Land (SW Spitsbergen).

Two t h e r m a l springs were d i s c o v e r e d by the P o l i s h A c a d e m y o f Sciences e x p e d i t i o n in April 1982 close to the eastern p a r t o f T o r e l l b r e e n ( M i g a l a & Sobik 1982). T h e following d e s c r i p t i o n o f the springs is t a k e n f r o m their a c c o u n t . One spring consists of a number of outlets over an area of 200 m 2 near the snout of the eastern part of Torellbreen. The discharge temperature was 12.3~ with an air temperature of -14.5~ discharge was estimated as _>101s-1. The second spring was located in the river bed made by water flowing from the Raudfjellet glacier, the discharge rate was 701 s -1 and the water temperature was 6.5~ (air temperature -12~ The glacier was ablated by the thermo-erosive effects of the springs. Migala & Sobik noted that the area is flooded by nival and fluvioglacial water in summer and consequently this area is best visited in spring or autumn.

Bockfjorden, Haakon VII Land (Hoel & Holtedahl 1911).

These springs are situated o n a n o r t h - s o u t h - o r i e n t e d line w h i c h crosses Sverrefjellet a n d coincides with the m a i n N - S fault line t h r o u g h B o c k f j o r d e n (Fig. 21.6). T h e r e are eight h o t springs in all, t w o to the n o r t h o f the v o l c a n o (the J o t u n springs), a n d six to the s o u t h (the Troll springs). A t all the localities there are large deposits o f t r a v e r t i n e a l t h o u g h the m o r p h o l o g i e s o f t h e t w o g r o u p s o f springs are different; the J o t u n Springs f o r m flat cones w h e r e a s the Troll springs have f o r m e d expansive p o o l s o f different sizes.

425

Jotun springs. The most northerly of the springs is just to the south of the Friedrich Glacier. The tufa deposit is pyramid shaped c. 70 m long and 60 m wide. The highest part is c. 60 m a.s.l., rising 2-3 m above its surroundings. The travertine is yellow or occasionally brown. The water flows slowly from openings which in vertical cross section have a dome-shaped profile. All the rocks in the vacinity are hidden under a thick crust of limestone. The second spring (c. 57 m a.s.1) is 500 m to the southeast of the first and morphologically very similar. The water temperature at the surface was 24.5~ The main part of the spring is elliptical and around 30 m long and 15 m wide. The main water flows out of an opening 20-30 cm in depth situated on the top of the tufa cone. The flow rate was higher than the one to the northwest. Troll springs. The Troll Springs are situated between Karlsbreen and Schjelderupbreen. There are six springs in all situated along a N-S-oriented line. The distances between springs, from the middle of one to the middle of the next are 200m, 150m, 250m, 100m, 120m (from north to south). The southernmost spring is 3 - 4 0 0 m from the moraine of the Karl Glacier. When Hoel and Holtedahl visited the area most of the springs had a high flow rate although many pools were entirely dry. Consequently, the pools of several of the springs were in a bad state of decay and almost totally destroyed in some parts. The pools formed by Spring number 3 (counting from the north) were all well preserved. The water flowed out at high discharge from a cauldronlike hole, which was 1.5 m wide, 3 m long and between one to two metres deep. The trough was filled with algae. The surface water temperature was 26.5~ which increased rapidly below the surface. In addition, large bubbles of gas rose towards the surface. From the trough the water traveled down a stream a few metres in length, within which the algae flourished, into the first pool. The water then flowed over the horizontal edge of the pool into the next pool and then again into the next. The largest basin was 8 - 1 0 m long, 2-3 m wide and 20-30 cm deep. In spring number 2 the discharge was similar to number 3 but there was not enough water to fill all the pools, consequently some were in a state of decay. At 0.5 m below the surface, the temperature was 28.3~ the highest temperature measured from this system of springs. The temperature of the water in the springs (except numbers 2 & 3) lies between 17.3 and 25~ The algae and other plants from the springs were examined; in particular the presence of Chara aspera var. spitsbergensis was important as it had never been found this far north before. Hoel & Holtedahl also mentioned that just to the south of the Nygaard Glacier there were travertine deposits similar to those at the Troll springs from which they inferred that there must have once been a spring there. Tempelfjorden.

Over t h e p a s t c e n t u r y a small n u m b e r o f expeditions have n o t e d the o c c u r r e n c e o f a circular h o l e in the w i n t e r ice in T e m p e l f j o r d e n . T h e descriptions are detailed in c h r o n o l o g i c a l o r d e r below. 1900-1901 Hoel & Holtedahl (1911) mentioned an observation made by a Norwegian, L. G. Nisja, from the ship 'Nordstjernen' during a winter harbour (1900-1901) in Sassenfjord in Isfjorden. Nisja had kept a daily meterological journal, which was later sent to the Norwegian Meterological Institute. As a result of his interest in the thermal springs in Bockfjorden, Hoel forwarded part of the journal by Graarud, a meterologist. In the middle of March, Nisja recorded a pool in the interior of Tempelfjorden which had not frozen all winter, even though Isfjorden was frozen all the way to the sea. At that time the pool had a minimum circumference of 500 m but it had been larger at the onset of the winter. On 30 March they towed a boat to the pool to record the depth and temperature of the water; the depth was 36.5 m and the temperature +I~ They tried to bring up water from the bottom of the bay for the temperature measurements, they still got the same result. Nisja states that throughout the whole winter the temperature of the opening was c. 2~ Hoel & Holtedahl noted that the temperature measurements taken by Nisja were almost certainly accurate because his thermometers were supplied by the Meterological Institute of Norway. Nisja also noted that at certain times turbulent eddies appeared to come up in the middle of the opening. 1920s D. A. Allen was one of the members of the Scottish Spitsbergen Syndicate Expeditions around 1919, 1920 and 1922 to the Btinsow Land area. He later described this feature of Tempelfjorden in 1940 in his Presidential address to the Geological Society of Liverpool (1941, p. 48) '... a curious basin at the inner end of Temple Bay, where, despite proximity to a large glacier, abnormally high temperatures have been recorded together with absence of freezing when Ice Fjord was covered with winter ice, and a state of commotion in the water noted'.

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CHAPTER 21

1969 A circular hole in the ice was observed and photographed in May 1969 by Navigator E. S. Pedersen. 1970 Two aerial photographs were taken in May 1970 of a circular hole in the ice by Navigator E. S. Pedersen who recorded it as having been in the same location then as the year before. When those photographs were compared (by W. B. H) to two oblique aerial photographs of the same area (NPI Le26.4 and .6) the position of the hole in the ice was estimated as latitude 78~ longitude 17~ and the NP coordinates as 1486 2116 (approximately 2 km up-fjord from Kapp Murdoch, 500 m from the north shore of Tempelfjorden). Given the temperature measurements of water in front of the glacier and the periodic bubbling seen, this is interpreted as a spring with gas. The temperature is too low for the bubbles to be water vapour and the water temperature is too high in this location for there not to be an injection of some warm water.

21.5

Neogene-Pleistocene marine sedimentation

N e o g e n e a n d Pleistocene sedimentation in Svalbard is principally c o n c e n t r a t e d offshore, west o f Svalbard a n d further to the south along the m a r g i n o f the Western Barents Shelf. I m m e d i a t e l y offshore western Spitsbergen, the reduction o f the Spitsbergian O r o g e n led to wedges of late Paleogene a n d N e o g e n e sediment blanketing earlier fault structures as seen in the sections of M a n n & T o w n s e n d (1989). A n u m b e r o f detailed studies d o c u m e n t the sedimentary sequences a l t h o u g h the correlation between studies is poor. This is due to a c o m b i n a t i o n of discontinuous reflectors a n d a laterally variable sediment supply to the areas o f interest especially in the case o f the u p p e r sedimentary units w h e r e the sediment supply was d o m i n a t e d by a small n u m b e r o f very large east to west drainage systems ( M y h r e & E l d h o l m 1988). Schltiter & Hinz (1978) recognized three sequences to the west of Spitsbergen which range in age from pre-mid-Oligocene to Pleistocene; the sequences are separated by two unconformities (U1 and U2). the sequences were named SPI-I, SPI-II and SPI-III where SPI-! is the youngest. SPI-III lies below U2. The erosion at the unconformity is highlighted by the top-lapping relationship of SPI-III against U2. U2 is dated as Early to Mid-Oligocene and dips gently westwards away from Spitsbergen. U2 is clear immediately to the west of Spitsbergen (north 76~ although it becomes increasingly difficult to identify it southwards; it is almost indistinct by 74~ (Myhre & Eldholm 1988). SPI-II (above U2) is of Pliocene age and thickens to the west (basinwards), exhibiting a chaotic seismic character interpreted as resulting from slumping and mass failure. U1, above SPI-1I, is similar to U2 in that it also shallows to the west, in contrast to SPI-II, however, SPI-I thins to the west and downlaps U1. SPI-I is observed locally to on-lap basement highs. To the north 78~ SPI-I can be divided into two sub-units. SPI-I is identified south of Svalbard to Bjornoya (Myhre & Eldholm 1988). They noted that U 1 of Schliiter & Hinz is equivalent to reflector E identified by Sundvor & Eldholm (1976). To the west of Svalbard the uppermost sedimentary units onlap the basement at the Knipovich Ridge (Myhre & Eldholm 1988). Andersen, Solheim & Elverhoi (1994) studied the Isfjorden fan area, they subdivided SPI-1 into two sequences, A (the younger of the two) and B separated by an unconformity (R4). Sequence B is identified across the whole of the Isfjorden and Bellsund fans and was interpreted to represent ramp sedimentation. On the shelf the unconformity R4 is angular. Sequence A comprises three lens-shaped units which are interpreted as an aggradational-progradational fan sequence in the Isfjorden Trough. The depocentre migrated north during fan growth (Andersen et al. 1994). Further to the south, along the western margin of the Barents Shelf, Spencer, Home & Berglund (1984) identified four sequences from late Paleocene to at least late Pliocene. They were termed I I I , iII and IV, where I is the oldest and IV is the youngest. The major contribution from Spencer et al. was the identification of the differing lateral extents and varied thicknesses of these units (Fig. 21.8). Unit I was believed to be of early Eocene to late Paleocene age, relative to the Senja Ridge this unit is thick in the Tromso Basin and is Eocene to Oligocene in age. In addition, Unit II is assumed to have been deposited, while spreading along the western Barents Shelf margin had reached 74~ Unit III is found west of the Senja Ridge and is Miocene to Pliocene in age, it thickens and progrades westwards. Unit IV was identified by Spencer et al. to thicken westward and extend over the whole Barents Shelf.

Fig. 21.8. Simplified profiles and submarine Tertiary stratigraphy of the Western Barents Shelf (from Spencer, Home & Berglund 1984).

Detailed work in the Hammerfest and Egga basins by Vorren et al. (1991) allowed correlation of their basin fills with the stratigraphy from further north described by Spencer et al. (1984). The Hammerfest Basin is subdivided into four units: ThA1 (oldest), ThA2, ThB and ThE (youngest). Unit ThA1 is equivalent to Unit i of Spencer et al. and is dated as mid-late Paleocene (Vorren et al.). ThA2 shows westerly and southwesterly progradation and is dated as latest PalaeoceneEarly Eocene, equivalent to the lower part of Unit II in Spencer et al. ThA2 unit downlap on to ThA1. Unit ThB is equivalent to the upper part of Unit II in Spencer et al. and in the Egga basin to unit TeB. Unit ThE overlies an angular regional unconformity and is composed of glacigenic sediments. The Egga Basin stratigraphy is divided into five units: TeA (oldest), TeB, TeC, TeD and TeE (youngest). The base of TEC is important as it is correlated with the base of Unit III of Spencer et al.. The base of TeE can be dated as approximately 0.8 Ma as the base of the unit represents glacial erosion at this time. Vorren e t al. (1991) related m u c h of the above information to a more regional perspective where they noted that from mid M i o c e n e to late Pliocene the Barents Shelf edge p r o g r a d e d between twenty and forty kilometres westward, whilst the Barents Sea was uplifted, resulting in the evolution of a fluvial drainage system. The Barents Sea area was dry land ( R o n n e v i k 1981; V o r r e n & Kristoffersen 1986; V o r r e n e t al. 1991) with a late Tertiary fluvial drainage system of two m a i n rivers (Fig. 21.10). Figure 21.11 shows the erosional areas of the Barents Sea from m i d M i o c e n e to present. There were a n u m b e r of glaciations of the Barents Sea f r o m 0.8 M a to present, these are discussed in m o r e detail in Section 21.7. The O c e a n Drilling P r o g r a m (ODP) explored the ' N o r t h A t l a n t i c - A r c t i c Gateways' between Svalbard and G r e e n l a n d in 1993 ( M y h r e & Thiede 1995) a n d three sites (910, 911 and 912) were selected on the edge of the Y e r m a k Plateau a b o u t 100 k m off-shore. In each case o f three or four cores taken, the greatest penetration is noted here. Site 910: 80~ 6~ water depth 556m, penetration 507m, Quaternary 70+ m, Pliocene 430+ m. Site 911: 80~ 8~ water depth 912m, penetration 506m, Quaternary c. 220-330 m, Pliocene c. 280-170. Site 912: 79~ 5~ water depth 1037m, penetration 209m, Quaternary 130+ m, Pliocene 70+ m.

NEOGENE AND QUATERNARY HISTORY

427

Fig. 21.9. Summary of the Neogene of the western Barents Shelf margin (simplified from Dowling, 1988, table 1).

Dropstones were encountered in ice-rafted sediments, mainly silt and clay. Other holes in the Fram strait (sites 908, 909), East Greenland Margin (913) and Iceland Plateau (907) penetrated down to late Oligocene, middle Eocene and middle Miocene respectively. Flower (1997) reported from site 910 on the Yermak Plateau that the core c. 19 to 70-90 m below seafloor, estimated at c. 660 ka, was an 'overconsolidated section'. He interpreted this as the result of loading by thick ice cover at that time and suggested that subsequently there was no firmly grounded ice there. A summary of the submarine stratigraphy of the Barents Shelf was collected by Dowling (1988, table 1), summarized here in Fig. 21.9. An extensive bioclastic carbonate deposit is developing (since 2600 yr BP) along the western Spitsbergenbank of the Barents Sea at depths between 50 and 80 m. The deposit comprises mainly filter feeding organisms; commonly M y a triucata, Hiatella arctica, Balanus balanus and Chlamys islandica and a wide range of other taxa with calcareous skeletons. They appear to flourish in near glacial temperatures. Shallower habitats are inhibited by iceberg disturbance and deeper by accumulation of fine mud that is washed out of the favoured habitat by strong currents, so forming olive grey and blue muds with lonestones and foraminifers (Andruleit, Freiwald & Schfer 1996). Submerged terraces in the southwestern Barents Sea were described by Levensbye & Vorren (1996). 21.5.1

Moffen

Moffen is an island of 4 to 5 km 2 formed of a storm beach and gravel perimeter surrounding a lagoon, 23 km due north of GrShuken just north of Latitude 80~ It would appear to be a Quaternary development possibly on a Devonian basement judging by the dominant Old Red Sandstone 'facies' of the shingle. Being a walrus sanctuary, it is not now permissible to visit the island. 21.6

Neogene-Holocene uplift and erosion

Svalbard. The present topography of Svalbard is the result of uplift followed by extensive erosion and glaciation. Krasil'shchikov et al. (1996, p. 8) in their commentary on an unpublished map,

Fig. 21.10. Interpretation of the Neogene fluvial drainage pattern in the Barents Sea (simplified from Nyland et al. 1992).

postulated eight groups of erosion surfaces: Holocene; Late Neogene; post-Paleogene; Late Cretaceous and Pleistocene; Late Cretaceous-early Paleogene; Cretaceous and Pleistocene; JurassicCretaceous and Pleistocene; and pre-Carboniferous. In their view the formation of modern land forms began in Pleistocene time with distinct elevation of the land. Clearly there is abundant scope for interpreting exhumed and reinforced ancient surfaces. Vitrinite reflectance data from the Central Basin indicates that 2.7 km of Cenozoic strata have been removed (Manum & Throndsen 1978a). V~tgnes & Amundsen (1993) pointed out that fjord incision accounts for 1 km of this which still leaves 1.7 km of strata eroded from above the present summit heights. Figure 21.10 shows the Late Neogene-Early Pleistocene fluvial drainage pattern in the Barents Sea. Uplift in Svalbard is elongated along the continental margin with a steep gradient towards the margin and a lesser gradient away from it (Vgtgnes & Amundsen 1993). The regional geothermal gradient coincides with the uplift area; Vgtgnes & Amundsen proposed that the present uplift is associated with a thinned mantle lithosphere which is backed up by the heat flow data and the geochemical signature of the Neogene to Pleistocene volcanic sequence, they concluded that the uplift can be explained by 'small scale convection where hot-spot-influenced asthenosphere abuts colder, deep, continental lithosphere'.

Western Barents Shelf. The initiation of uplift and erosion of the Stappen High was believed by Wood et al. (1989) to have coincided with the change in spreading direction at Anomaly 13 time involving up to 3000 m of erosion. The Loppa High has also been subjected to a significant amount of erosion, much of which was Late Jurassic to Early Cretaceous. However, it was rejuvenated at the time of rifting of the western Barents Shelf. It therefore underwent a second phase of erosion in response to thermal uplift

428

CHAPTER 21 and a general sea level fall in the late Tertiary, followed by glacial erosion (Wood et al. 1989) (Fig. 21.11). Nyland et al. (1992) studied Tertiary uplift and erosion in the Barents Sea using vitrinite reflectance data to estimate erosion and concluded that the magnitude of uplift and erosion increased to the north and northwest. A well in the Hammerfest Basin showed 1100 m of erosion and more than 2000 m of erosion was reported from the Stappen High and Bjornoya (reaffirming erosion estimates of Wood et al. 1989). Fission-track analysis on samples from the southwest Barents Shelf by Nyland et al. (1992) resulted in two distinct periods of uplift and erosion: 40-50 Ma ago and 5-10 Ma ago. They attributed the earlier uplift and erosion cycle to the structural development associated with the early stages of rifting of the Norwegian-Greenland Sea. The 5-10 million year period was interpreted by Nyland et al. as reflecting the isostatic uplift in response to deglaciation even though the earliest indications of the start of glaciation in the surroundings of the Norwegian Sea are not seen until 5.45 Ma (Jansen et al. 1990). Reemst et al. (1994) investigated the mechanisms for Cenozoic uplift and erosion and correlated them with sea level changes and regional tectonics by using models of basin formation. They modelled a Mid-Miocene fall in sea level combined with glacial erosion in addition to an increase in the level of Pliocene and Quaternary intra-plate stress, which fitted the stratigraphy. Knutsen & Larsen (1997) used seismic and gravity studies of the Sorvestsnaget Basin in the southwestern Barents Shelf as a clue to regional tectonostratigraphic events. Following the Late Cretaceous and Paleocene shear movements along the Senja Fracture Zone with related uplift and erosion of the west of the basin, the next conspicous uplift appears to have been Oligocene and Miocene transpression related to reorganization of plate motions in the Norwegian Greeland Sea, events strangely opposite to those in Svalbard. At the same time salt diapirism was influential. Late Neogene and Pleistocene westward prograding sedimentation developed.

21.6.1

Fig. 21.11. Map of the Barents Sea delineating the main erosion areas from mid-Miocene to Recent. Also outlined are the main structural elements of the western Barents Sea (adapted with kind permission of Elsevier Science, Amsterdam from Vorren et al. 1991).

Neogene shaping of Svalbard

(a) The shape. Most of Spitsbergen exhibits a certain uniformity of summit heights of its mountains. If these are contoured, as by Harland (1969a), a relatively smooth envelope may be derived (Fig. 21.12). This surface, touching the tops of the higher mountains, ranges roughly between 600 and 1600 m a.s.1. There are four noticeably higher areas. (i) In southern Ny Friesland a distinct maximum focuses around the granitic plutons. The granites are conspicuously less resistant to denudation than the country rock so that its relative buoyancy would determine its uplift. (ii) In the southern part of the northwest sector of Spitsbergen, centered on Holtedahlfonna, is a more gentle positive area. No cause is suggested for this location. (iii) Centred on the core of the Paleogene outcrop in the Central Basin is a relatively flat positive area contrasting with its surround. To refer to this as 'basin inversion' simply poses the question in another form. It may arise from the lower density of the Paleogene sediments. (iv) In Wedel Jarlsberg Land and northern Sorkapp Land is a well-defined ridge-like feature containing the high mountains of Hornsund and their northern extension along that fold belt of the West Spitsbergen Orogen. There appears to be no feature corresponding to the larger part of the fold belt in the orogen to the north. The relatively low heights of the basement in the same orogen may be in part the result of significant basic rocks there. Ignoring the steep slopes at the coastlines the general trend of the surface is to slope down towards the east and southeast. The main reason for a weak Paleogene orogenic topographic signature may be the lack of a deep 'sialic root' to give it continuing buoyancy.

NEOGENE AND QUATERNARY HISTORY

(v)

(vii)

(viii) (ix)

429

also at some time, if the 1000 m relief of the envelope was not already a denudational phenomenon then, uplift of the higher parts was generated by differential thermal expansion and/or inversion aided by the lower density of the body of the Van Mijenfjorden Group because it is less tectonized (than earlier strata); during and after events (iv), (v) and (vi) erosion cut into the raised surface and by development of large river valleys dissected the plateau in stages towards the present relief; glaciation continued the process, with ice cover protecting some areas, but with active erosion of others by nivation; to what extent sea level rose to flood the valleys or glacial erosion below sea level excavated them is a further question.

(c) The timing of events. There is little constraint on the timing of the above events. (1) The initial peneplanation (events (i) to (iii)) beginning in Eocene time probably extended through Oligocene time with drainage from the orogen eastwards and westwards partly into the graben and probably onto Greenland. (2) The reversal of drainage from the orogen with sediments transported westwards may be related to the change of Spitsbergen from a position tight against Greenland to an opening of the Greenland-Norwegian basin capable of receiving sediments. If these sediments could be dated and their volumes estimated there might be some evidence for the timing of the above events. (3) The Miocene plateau basalts (c. 10Ma) indicate the existence of a peneplane prior to its dissection and therefore probably before its relative uplift. (4) Thereafter the sequence of glacial stratigraphy may give some clue; but more information is unlikely because the later glaciations removed much of the earlier record. Fig. 21.12. Summit height envelope contours of Svalbard (redrawn from Harland 1969a).

21.6.2 The questions arise as to the nature of this enveloping surface and its history. The smoothness of the surface, which may be an artifact in part, suggests that it was either a peneplain or a mature and subdued landscape. In both cases a base level at around 600 m in the west and perhaps 400 m in the east is suggested. This implies a combination of an earlier eustatic level combined with differential isostatic uplift. Extending the trend to the whole of the Barents Shelf, part of the explanation for the existence of Svalbard above sea level may be its proximity to the northwest corner of the shelf, where to the north was the ocean-spreading of the Eurasian Basin and to the west was that of the Greenland-Norwegian basins. On this basis, allied to a continuation of the long term cooling and contraction of the mantle beneath the Barents Shelf, where it is covered by sea, differential expansion of the mantle occurred, especially at the northwest corner related to the two adjacent ocean spreading zones. This is an explanation for the existence of the Svalbard archipelago north of the Barents Sea with successions of cover rocks above sea level to the north and west and below sea level to the south and east (Harland 1969a). In this region of relative uplift and subsidence there was certainly an interplay with eustatic changes of sea level.

(b) The sequence of events.

(i)

(ii)

(iii)

It seems likely that:

the erosion of the West Spitsbergen Orogen, evident in the sediments of the upper formations of the Van Mijenfjorden Group, probably continued until most of the orogen was reduced to near sea level; the sedimentation progressing eastwards was balanced and later replaced by drainage into the newly opened Norwegian-Greenland Sea; at the same time the Miocene plateau lavas erupted and covered parts of the peneplain;

Quaternary development of land-forms

How much of Svalbard's morphology was formed before the Pleistocene Epoch is uncertain. It is clear, however, that the detailed sculpture of the land by glacial, fluvial and marine erosion made the landscape as it is now. In particular, the steep cliffs of glacial valleys and the coastal features of strandflats and sea cliffs, make geological exposure a remarkable scientific cornucopia. The current rate of retreat of the steep carbonate cliffs north of Tempelfjorden was estimated at 0.05-0.5 mm a -1 (Rapp 1960).

21.7 21.7.1

Glacial history of Svalbard: Neogene-Holocene Glacial episodes

De Geer (1900b) was one of the first to consider glaciation in eastern Svalbard. Perhaps the easternmost observations were by Jonsson (1983) on Storoya. Glacial episodes in the surroundings of the Norwegian Sea are identified as early as 5.45Ma (Jansen et al. 1990). They also document a number of glacials before 5 M a and at 4.5 and after 4 Ma at 3.9, 3.7, 3.5 and 3.2Ma. There were low ice volumes in the period 4.6 to 4.2Ma. Between 2.57 and 2.35 Ma there have been major glacials (Jansen et al. 1990; Jansen & Sjoholm 1991) with 'cooling and possible mountain glaciation in the late Miocene' and from 2.57Ma onwards the repetitive glacials resulted in the deposition of true glacigenic sediments (Jansen et al.). There was an intensification of glaciation at 1 Ma, according to Jansen & Sjoholm, although Jansen et al. placed this intensification earlier at 1.2 Ma, after which large North European ice sheets first formed. As a result of this increasing severity of the glacials, the interglacials gradually became warmer until 0.6Ma (Jansen et al. 1988).

430

CHAPTER 21

There are differences of opinion as to whether the Barents Sea was ever glacierized. In favour, De Geer (1919) first suggested extension of ice over Svalbard from a centre to the east which would also have extended to the continental slope. These ideas have been followed by Gronlie (1924), Hoppe et al. (1969), Hoppe (1981), Mercer (1970), Baranowski (1977), Grosswald (1980), Denton & Hughes (1981), Elverhoi & Solheim (1983) and by Solheim & Kristoffersen (1984) and Vorren et al. (1989 et seq.) Interpretation of submarine data provided much of the evidence. The concept of glaciation of the Barents Sea has been opposed by Boulton (1979a) on the basis that such a major ice sheet is inconsistent with the exposed stratigraphic record on Svalbard. Matishov (1977) supported this viewpoint from a study of submarine samples. Boulton did not deny the possibility of a more extensive Pliocene glaciation which might account for some of the submarine evidence used by the others. Mangerud et al. (1992) reported on the last glacial maximum on Spitsbergen and Polyak et al. (1995) on two-step deglaciation of the southeastern Barents Sea. Prins Karls Forland supports high beaches (Peach 1916) and according to Miller (1982) some were not disturbed by glaciation since at least 90 ka. The Barents Sea was probably not glacierized until 0.8 Ma, after which it was repeatedly glaciated, in some cases by grounded glaciers (Solheim & Kristoffersen 1984; Vorren et al. 1989). The glacial advances are suggested by the number of glacial unconformities in the Barents Shelf sediments. Solheim & Kristoffersen documented at least four glacial advances which reached the western Barents Shelf edge. Ice reached the Barents Shelf just after 22 ka (Elverhoi et al. 1983). Immediately prior to 21 ka the ice sheet extended over most of the Barents Sea although there was an embayment close to the outer shelf; Vorren et al. (1991) presented sedimentological data (unit 5 W) in support of an inner bay area in the ice sheet approximately 400 • 300 km through the period 21-18 ka. From 19 to 16 ka, most

Fig. 21.13. Diagrammatic model of the chronology of the deglaciation of the western Barents Sea (simplified with kind permission of Elsevier Science, Amsterdam from Vorren et al. 1989).

of the Barents Sea was glacierized (Vorren et al. 1988); the last glacial maximum (Weichselian) was at 18 ka (Jansen et al. 1990) when the ice sheet advanced westwards almost to the shelf break (Fig. 21.13 from Vorren et al. 1991). The Weichselian glacial episode is well established by sufficient evidence for all to agree (e.g. Andersen 1981) and may even be divisible into three events: early, mid- and late. It was the last major glacierization of Svalbard and probably removed most traces of earlier glacial events. The Late Weichselian event has been estimated at about 18ka (Miller 1982) and 12.6-10ka by a4C (Boulton et al. 1982), whereas Troitskiy et al. (1979) had obtained by different methods 33 and 47ka and Mangerud & Salvigsen obtained an approximate age of 46.3 ka from 14C on an in situ shell. The above spread of values may not be inconsistent for such a complex episode with varied manifestations in different places based on somewhat speculative age interpretations. According to Vorren et al. (1988) the deglaciation occurred in two steps; 16-13 ka and 13-10 ka. The deglaciation rate of western Svalbard was slow during the first period (Mangerud et al. 1987) then during the second period the ice margin retreated to mid-inner fjord along the western coast of Svalbard, although the eastern areas were still glaciated. Polyak et al. (1965) described two phases of accumulation of glaciomarine sediments in the Barents Sea between c. 12.7-12.1ka and c. 10.5-9.4ka. The interval of nondeposition corresponds to cold conditions and permanent sea ice. Ice had retreated completely from the shelf by 9.4 ka (Vorren et al. 1988; Polyak et al. 1995). Troitskiy et al. (1979) postulated the following correlation, with ordinal numbers introduced here. (1) Saalian: Lower till, Billefjorden and Broggerhalvoya 130 ka (2) Eemian: Lower marine till, Billefjorden 94 and 80 ka (3) Early Weichselian: Lower till, Bellsund and upper till; Billefjorden (4) Mid-Weichselian: upper marine unit, Bellsund (5) Late Weichselian: upper till, Bellsund. Whereas Boulton et al. (1982) listed six events numbered with increasing age but listed here in time sequence. (6) Glacial event before 115 ka predating last intergalcial (5) glacial event before 70 ka, as (6) or Early Weichselian (4) major advance to western Spitsbergen coast (3) glacial advance ending 35 to 40ka (2) 'Billefjorden' [=Bellsund] stage, with major expansion of ice dome in the east and advance beyond present margin in west between 12 and 10ka the eastern domes had disappeared by 9.8 ka (1) little ice age with advances of 12 kin. Following the above scheme, the case made by Boulton (1979a, b), based largely on raised beach and stratigraphic evidence on land, was that there was a major (Weichselian) glaciation at about 40 ka (or Wisconsin) followed by beach formations raised up to 80 m a.s.l., with the following deglaciation. On his model, there was no equivalent glaciation until his BiUefjorden glacial stage from 11 to 10 ka which was the last significant glacial advance, followed in central Spitsbergen by further raised beaches (as so well seen in Billefjorden). These conclusions were challenged by Blake (1981) and countered by Boulton (1981) who also argued for a lack of significant glaciation between c. 40 ka and 12 ka. This brings us to the Holocene story with more precise age estimates based on a stratigraphic record, mainly in raised beaches. It is more complete because it it is largely undisturbed by significant glacial advances during this interval. However, the initial Holocene ice cover was significantly less than at present (Ahlmann 1948) reaching the minimum extent during the Post-Glacial Warm period about 8 k a (Semevskiy & Shkatov 1965). Then around 2.5ka glaciers again advanced (Feyling-Hanssen 1955a, b, c). The evidence of glacier fronts returning with the 'little ice age' is recorded in historical reports. Anecdotal observations of advances and retreats of glaciers may not correlate directly with changes in climate for at least three reasons: (i) The as yet unpredictable surging of glaciers may lead to rapid advances. Notable examples are seen in successive charts of the southern coastline of Nordaustlandet where Brhssvellbreen

NEOGENE AND QUATERNARY HISTORY advanced 21 km along a 30km front into the sea during the present century. Similarly within Van Keulenfjorden, Nathorstbreen appears to have advanced and retreated about 12 km. (ii) The advance and retreat of glacier fronts depends greatly on the topography and bathymetry. Ice cliffs exposed to the sea may retreat rapidly especially if floating. The coastlines change rapidly in this respect so that the year of a survey generally gives the ice margin on large scale maps. During the last few years (1991-1993), for example, Blomstrandhalvoya (peninsula) has become an island and on a much larger scale the rapid retreat of the ice front at the head of Hornsund might lead to the separation of southern Sorkapp Land as an island if the subglacial surface is below sea level. (iii) Fluctuations in snowfall at the source of glaciers are manifested in fluctuations at the snout after a delay depending on the length of the glacier and the rate of flow. Nevertheless, putting all data together it appears that the ice fronts as based on reliable maps at the end of the nineteenth century, were as advanced as at any earlier Holocene time and were advancing (Garwood & Gregory 1898). Almost from the beginning of the Twentieth Century there has been a general retreat often documented in great detail. Nordenski61dbreen front in Billefjorden has been surveyed many times (Harland 1952), and Von Postbreen in Sassendalen. Birkenmajer (1964b) using earlier observations by Heintz (1953) plotted a succession of seven recorded fronts from 1900 to 1988 in Hyrnebreen, Hornsund. Retreat stages up Adventdalen, from moraines and landslides were recorded in detail (Sawagaki & Koaze 1996).

21.7.2

Moraines

Moraines are the most obvious effects of glaciers and the primary evidence of their former existence. Median and terminal moraines provide convenient samples of the country rock upstream becoming more evident downstream as the ice ablates or melts. In the current state of general retreat many of the terminal moraines are ice-cored and occasional retreat stages may be marked. Advancing ice may push not only the previous terminal accumulations, but thrust into marine sediments and raised beach deposits. This is a vast subject inseparable from the study of glaciers and their motions, which are discussed further in the final chapter (Boulton 1967, 1968, 1970). The evolution of morainic landforms was described from Adventdalen (Sawagaki & Koaze 1996). Till, petrography and petrogenesis with their elaborate terminologies will not be discussed here as with the petrology of most other rocks encountered (Boulton & Deyroux 1981).

21.7.3

Submarine glacier-fed sedimentation

Submarine surveys also revealed evidence for massive slumping and gravity flows, with the cutting of downslope re-entrants, and flows of between 8 and 15 km in length. Hundreds of cubic kilometres of sediment were deposited on the ocean floor especially off the continental slope north of Spitsbergen. The age of these events could be Weichselian (c. Wisconsin). Such processes are typical of glaciomarine sedimentation. Lloyd et al. (1996) described a representative ice rafting history from the Spitsbergen ice cap over the last 200 ka. Based on piston cores from the upper continental slope of the Spitsbergen margin they identified ice-rafted debris by abundance of clasts (2+ ram). Abundances were interpreted in six levels (youngest to oldest) with peak debris in levels: stage 6 (150-c. 130ka); stage 4 (75-60ka); stage 2 (26-15 ka). In the interglacial substage 5, of five substages (b) and (d) identify distinct interglacials. They postulated different sources of sediment: for stage 6 summer melting of a large ice mass; advance of Spitsbergen ice cap during interstadial stages 5 and 3 because of increased moisture supply; and for stages 6-5e, 5b-5a and 2-1 boundaries, disintegration of a large ice mass on the continental shelf. These provide a means of correlation with the land-based evidence.

431

Laberg & Vorren (1996) demonstrated an extensive submarine sedimentary fan at the mouth of the Storfjorden trough where it tips over the continental slope. They argued that seven middle and late Pleistocene glacial advances to the shelf break resulted in episodic high sediment input with sedimentation rates of up to 1.72 mm a -1 separated by sediment standard interglacials. The glacier margin was near or at the shelf break. River-fed fans were dominated by turbidity currents, whereas glaciers fed typically debris flow deposits. Within a more restricted proximal fjord environment Lonne (1997) detailed Weichselian deposits preserved in terraces in Linn6dalen (opening into southwestern Isfjorden just west of the Festningen section). These showed on a small scale many of the typical features of turbidite deposition from an ice front and terminating in a sand-lobe.

21.7.4

Submarine glacial plowmarks

Subaerial striae are preserved on more resistant rocks (e.g. Str6mberg 1972). However, an offshore result from side scan sonar in the Yermak Plateau region was the identification of deep Pleistocene iceberg/pressure ridge plowmarks (Cherkis et al. 1992; Vogt, Crane & Sundvor 1994). Relict gouges formed by the keel of floating ice masses were recorded at depths between 450 and 850 m. Sea levels could have been 100-150 m lower than at present. The marks were interpreted as the effects of calving from the BarentsKara ice sheet. That shallower marks were not observed suggests that grounded ice sheets may have occupied and/or smoothed off the record which was preserved in deeper water. The age of these events is uncertain. A Weichselian-Wisconsin glacial maximum is most likely, corresponding to Boulton's 40 ka glaciation. However an age of 660 ka was suggested for ice sheet grounding on the Yermak Plateau (Flower 1997).

21.7.5

Uplift and subsidence in relation to glaciation

The climatic effects of major uplifts have been considered especially in relation to the Tibetan Plateau both directly as a geomorphological factor and from extensive weathering affecting atmospheric composition. Such effects would be slow in relation to the Milankovich-type cycle and might bring in sufficient general cooling so enabling orbital cycles to trigger glaciations. It had already been suggested that the subcrustal heating and expansion of the mantle, which caused the separation of Eurasia from Laurentia through Cenozoic time, also resulted in general uplift of the margins of the separated continental lithosphere so exposing i.a. Spitsbergen at the margin of the Barents Shelf (Harland et al. 1969a). Eyles & Young (1994) developed these ideas in relation to the North Atlantic-Arctic region. He argued for passive margin uplift beside the developing Eurasian and North Atlantic basins as an effective (?additional) factor in Northern Hemisphere late Cenozoic glaciation. Lebesbye & Vorren (1996), from seismic interpretation, identified two semi-continuous terrace zones extending 350 km along the flank of the southwestern Barents Sea floor. They are at relatively uniform depths of c. 150 and c. 220 m. They were interpreted as wave-cut platforms formed between 0.8 and 0.2 Ma and indicating diastrophic subsidence of between 0.2 and 0 . 9 m k a -1. Their relationship to glaciations is obscure but an interglacial origin was preferred.

21.8

Pleistocene and Holocene surficial geology and geomorphic features

Quaternary sediments in Svalbard are composed primarily of Pleistocene and Holocene glacial deposits and Holocene raised beaches, talus cones and boulder fields

432

21.8.1

CHAPTER 21

Glaciofluvial-fluvial sediments

Most glaciers that do not reach the sea, terminate in valleys occupied in summer by braided glacial streams. These are generally charged, not only with fine sediment that may reach the sea, but with boulders and gravel that are dispersed across the fluvioglacial plain. There is generally a wide apron of coarse gravel with constantly changing anastomosing streams. Inliers of solid rock may protrude as isolated inselbergs or restrict the valley sides. Occasional lakes and lagoons near the sea may form and so trap the finer sediments. In general, however, the energy of the early summer snow melt-stream tends to sweep away finer sediments when the new stream changes course.

21.8.2

Alluvial fans, talus cones and rock glaciers

Related to the gently sloping glacial outwash plains are the fans that develop at the foot of mountains and are supplied with less rounded rock fragments by occasional mountain streams that result from the spring and summer melt of snow. The pattern of the often intermittent water courses rather than of anastomosing streams tends towards that of a distributary delta. The boulder to gravel deposits may merge into the valley alluvium, but generally do not travel far beyond the mountain foot. A quite typical feature of most mountain slopes with more and less resistant beds, especially where strong strata are relatively flatlying, is an hour-glass appearance in which at the horizon of more resistant strata the wide talus chute narrows, often to a gulley, and spreads out below into a talus cone and a fan with distribution channels. The waterways may exist only at times of extreme melting. Generally the slope is near the angle of rest, and is seldom stable for long. Such features are typical of low rainful environments. Spitsbergen mountains often have the appearance of cold deserts and, indeed, the annual precipitation is commensurate with a desert environment. Talus morphology was discussed by Akeman (1984) and talus terraces by Liestol (1962). Anhydrite-gypsum, which would dissolve with warmer rain, forms steep cliffs and bluffs in this cold dry environment. Solifluction lobes result from down-slope flowage when the excess water in frozen soil greatly weakens it when thawed. Perhaps the most extreme solifluxion is found in the lower reaches of moraines on ice with a consistency of newly poured concrete. Rock glaciers are simply an exaggarated form of soil creep in talus slopes or cones (e.g. Swett, Hambrey & Johnson 1978, 1980). Ice cores deform down slope as do glaciers, superficially aided by freeze-thaw processes and occasional advances. In any case they may flow out some way onto level ground. Icings occur typically as sheets of ice some metres thick over the valley floor where melt water streams emerge from glaciers. Some ice may survive into the next winter.

21.8.3

Raised-beach morphology

Perhaps the area that best exhibits raised beaches is in the fjords that extend into the heart of Spitsbergen such as Billefjorden (Balchin 1941; Feyling-Hanssen 1955a). Beach deposit faunas were investigated in further papers. From the sea these appear as conspicuous scarps where later marine erosion has cut into the soft deposits whose bedding surfaces comprise successions of ancient parallel beach ridges. Balchin, who first surveyed these features, concluded that their sedimentary surfaces dipped at angles of up to 1~ and indicated subsequent tilting (?with some faulting) with differential isostatic rebound. Feyling-Hanssen on the other hand interpreted the surfaces as original depositional features sloping away from the principal sedimentary source. Neither interpretation is wholly adequate when other occurrences throughout Svalbard are taken into account. As already indicated, heights above sea level are

more meaningful generally than Balchin's hypothesis would allow, whereas there are differences implying regional but gentle tilting from flexturing of the crust. Changes in the beach ridge morphology on Broggerhalvoya (southern shore of Kongsfjorden) raised beach gives some indication of the relative sea level changes (Forman, Mann & Gifford 1987) since 13 000 abe. The breadth of a raised beach ridge is assumed to be related to the rate of relative sea-level fall. Slow fall produces wide ridges and more rapid falls result in narrow ridges. At Broggerhalvoya (as described by Forman et al.) at altitudes between 20 and 45 m above sea level there are three large ridges (at 29, 37 and 45 m above sea level) up to 5 m in height and 200 m in width. In contrast, below 20 m above sea level, there are many low, narrow ridges/strandlines. At the present shoreline, there is a large barrier beach being developed which represents a stillstand or transgression. The 37m beach ridge is dated at l 1 9 0 0 + 4 3 0 a B P and below 30m above sea level is dated as 1 0 4 1 5 + 9 0 and 9370 :t: 340 a ae. On the north shore of Kongsfjorden a date of 6 0 4 0 + 2 1 0 a a P has been found at a height of 5 m above sea level. The emergence of Broggerhalvoya is proposed by Forman et al. to have commenced c. 13 ka BP followed by a relatively slow rate of sea-level fall, with three periods of still stand or transgression. The rate of sea-level fall increased after 10 ka BP, coinciding with the final local deglaciation of Spitsbergen. The date of 6 ka he was assigned to the mid-Holocene transgression, termed the Talavera Transgression, when sea level was similar or above present level. In regional terms the relative sea-level change reflects a two stage glaciation of Svalbard (Forman et al. 1987): (1) initial unloading involved the disintegration of the Barents Sea ice sheet on Spitsbergen Bank, (2) approximately 10kaBP the deglaciation of the major fjords in Spitsbergen commenced.

21.8.4

Permafrost and patterned ground

As mentioned in Chapter 1 the islands of Svalbard are subject to a permafrost regime. Hjelle (1993) noted that the ground is perennially frozen down to between 100 and 400 m below the surface. This applies only where there is no regular cover of water or ice, each of which is reflected in the sub-permafrost contours. The lower surface is at approximate equilibrium between surface cooling and geothermal flux (see also Jahn 1961). Huxley & Odell (1924) and Elton (1927) were amongst the early scientists in Spitsbergen to address the problem, followed by Kulling (1937) in Nordaustlandet. The most conspicuous effect of permafrost is at the ground surface where summer weather thaws the frozen ground down to 1.0-1.5 m. It freezes again each winter so that the layer becomes active, especially with the spring thaw and autumn freeze. This active layer is confined below by the frozen soil or rock with consequences typical of most Arctic environments, seen in patterned ground (Fig. 21.14), and in pingos. Patterned ground is widespread in Svalbard tending to polygonal arrangements in flat ground and on gradients to down-slope stripes. With appropriate slope environments and sufficient exposure in the summer these features may occur at all altitudes from mountain tops and slopes to coastal strand-flats. A degree of stability, with protection from annual disturbance as by meltstreams, is necessary because the structures result from cumulative results of the activity over many years and once formed they persist and tend to be reinforced. An interesting aspect is that the subsurface materials may vary greatly and each material tends to yield its own distinctive surface structure. For example, a survey in 1949 (unpublished) of the stone polygon types on the flat top of Teltfjellet (Campbellryggen, Billefjorden) reflected in remarkable detail the variation in the underlying carbonate lithologies. Pingos, on the other hand, depend on particular circumstances. Even so Hjelle (1993) noted that about 80 had been reported in Svalbard. They are found in relatively flat valley floors as conical

NEOGENE AND QUATERNARY HISTORY

433

m o u n d s up to 40 m high similar to the M a c k e n z i e D e l t a type. T h e y have a core o f solid ice which a c c o u n t s for their height (Piper & P o r r i t t 1966; Liestol 1977; Y o s h i k a w a & N a k a m u r a 1996).

21.8.5

.

~:

:i::..

(b)

"

~

processes

T e m p e r a t u r e fluctuations above a n d below freezing point, w h e t h e r over a diurnal or an a n n u a l cycle, result in a variety o f processes (Williams & Smith 1989). Svalbard supports a rich a s s o r t m e n t o f these effects a n d is an ideal l a b o r a t o r y for their study.

(a)

9

Freeze-thaw

~

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=o,,ve ' ,.,or

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III I I I I I I III I l i l I I I I II I I II I IIII I IIP, I l ERMAFROST~ ' i - - ~ s

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III I I II I II III III II I I I I

(c)

Fig. 21.14. Diagrammatic illustrations of patterned ground. (a) Stone circles tend to develop from approximately equidistant centres, the stones being separated in ridges at the circumference from mud in the centre, the intervening ground being unsorted. (b) Expansion of circles presumably leads to the typical polygonal pattern, ideally hexagonal, the pattern depending on the initial distribution of active centres. A typical polygon on flat ground would be about 2 m in diameter. The mud centre often dries out with polygonal desiccation cracks during the summer. (c) Cross-section in summer of a polygon with mud in the middle and a stone or vegetated periphery. The arrows show the observed circulation at the height of the thaw. (d) With lower temperatures contraction cracks develop in areas of colder climatic regimes. The initial cracks are primary and tend towards a more trapezoidal quadrilateral pattern. The borders are raised by repeated infilling of cracks and the centres may be depressed with pools and mud. The dimensions are greater by an order of magnitude or more than that of the polygons. This outline was based on a photograph in Williams & Smith (1989, p. 170).

Nivation is a denudational process on a diurnal cycle, limited to the summer, is typical at an ice-rock boundary as at the head wall of any permanent ice or in a bergschrund. Day-time melting of snow at the surface, especially on the rock, leads to a trickle of water, often down the rock face to where the ambient temperature is below zero. The warmer water penetrates this zone, melting the ice at the rock surface. At night the supply of meltwater ceases and the water in the narrow contact zone freezes. Successive expansive freezing moves the original ice away from the rock surface and, if it has penetrated cracks in the rock, the same ratchet process will in due course separate the rock fragments from its parent and so supply the ice with debris that moves down hill as moraine. It thus erodes the rock face in a generally steep or vertical cliff (e.g. McCabe 1939). This is one of principal process in the erosion of corrie and glacier head walls and sides and is more active in Spitsbergen on south-facing slopes. Uplift of stones in 'soil'. The thermal conductivity of silts and clays increases markedly with increased water content and that of water increases four-fold on freezing. Most stones have higher thermal conductivity than soil or ice. Moreover, soil water is drawn towards ice where it freezes on account of free energy often referred to as (cryo)suction. Consequently as winter temperatures prevail stones will tend to a lower temperature than adjacent soil and so attract ice growth at the stone's surface. This is generally greater beneath where the soil is wetter. Thus the stone is heaved up by ice forming beneath the stone. This may occur even without underlying permafrost. Walking of stones on ice. Moraine generally protects the ice beneath from ablation. However larger rocks may move across a level glacier towards the south when the glacier ice melts leaving the rock on an ice pedestal which melts in the southerly sun's rays and topples over. Cryoturbation (apparent convection cells). In the active layer above permafrost the above processes in level ground become localized in nearequidistant centres of cycles or polygons (Fig. 21.14). At the winter freeze in each cell, water is drawn to the freezing surface and the upper permafrost surface so forming ice with consequent heave at the expense of contracting intervening mud depleted of its water. At the summer thaw the process reverses with gain of water in the soil from both melting ice above and below and thawing snow above, so becoming mobile. The net effect at the centre of the cell is to develop a convex subaerial surface and a depression beneath it in the permafrost. From the dome, mud will tend to flow outwards and stones be pushed faster on freezing to form a perpheral stone circle or polygonal network. There is a general agreement that the kinematics of the development of circles to polygons is one of apparent convection with upward motion in the centre, outward motion at the surface to the periphery and downwards and inwards back to the depressed centre at the permafrost surface. Different densities at different temperatures are the motive force as in thermal convection. It has been suggested that the convection effect of density differences could not be enough to cause the observed structures, e.g. by Williams & Smith (1989). On the other hand, Hallet & Prestrud (1986) argued that the excess of water in the mud on thawing would drain downwards as the surface mud tended to dry and thus the lower layer of water-rich mud would be significantly more buoyant than the drier mud above. Thus a density instability and convection could ensue, causing the uplift in the centre with a slope outwards. Stones in the mud would accentuate this circulation by heaving upwards and then outwards when freezing temperatures resumed. It would seem that a combination of density-driven and ice-heave circulation may satisfy all observations. The rates of motion vary from an upward motion at the centre of say 10% of the depth of the active layer. Nevertheless H a l l e t & Prestrud suggested that patterned ground developed through an interval of up to say 9000 years on a stable surface. The above processes result in different effects according to circumstances.

434

CHAPTER 21

On flat surfaces an active layer will tend to generate equidistant cells which result in circles or polygonal networks. On sloping surfaces the effects will be linear downslope near the top (stone stripes) and approaching a lower angle transverse solifluction lobes may develop. Available materials have a profound effect with patterns largely of mud or of stone and when both materials are available the stones concentrate at the borders with raised mud dome in the middle. Vegetation may concentrate in the marginal trenches or if more abundant vegetated hummocks are reinforced by their tops being exposed first from melting snow-cover. Thermal contractioncracks. At temperatures - 5 ~and below, ice contracts in volume. The above polygonal network may be reinforced by cracks along the peripheral trenches. In large flattish areas with little winter snow-cover a large scale network of ice and then sediment-filled wedges develop. The pattern seen from the air is often on a larger scale and the shapes tend more towards a trapezoidal quadrilateral rather than a hexagonal pattern. Successive winter freezing and summer thaw tend to raise the margins of repeatedly infilled cracks leaving depressed areas in the middle. Desiccation cracks. On a very much smaller scale the mud surfaces of polygons dry out in the summer and a finer set of polygonal cracks develop. These may persist and reinforce other structures if not obliterated by mud flow in the spring. They are characteristic of the cold desert environment of Svalbard. Pingo formation. This is generally a consequence of a patch of ground without underlying permafrost which becomes exposed to freezing winters. A gravelly patch may result from a drained pool which in turn may be the result of depression from the melting of subsurface ice in a thermokarst terrain (with kettle holes). Water is sucked from the coarser sediment so forming an ice layer. The sediment being coarse does not contract in consequence and allows more water to pass through it to the growing ice wedges which thus may form a dome. In some cases there may be some hydrostatic, (artesian) water pressures involved if at the foot of a mountain (Williams & Smith 1989). Svalbard pingos have been described by Piper & Porritt (1966) and Yoshikawa & Nakamura (1996) from studies of the pingos in Adventdalen. They showed that water in open-system pingos comes from beneath the permafrost, near the shore by a lagoon formed less than 140 a BP. Rebound uplift, from glacial unloading, is indicated by older pingos further up the valley, respectively less than 2.8 ka BP and 7 ka BP.

21.9

Post-glacial sea-level changes

From a global perspective there were two early Miocene transgressions, the more pronounced of the two was in earliest Aquitanian and the second started in latest Aquitanian and continued through until Langhian. There was a rapid sea-level fall at the end of this interval in Langhian and then a further sea-level fall at the end of Serravalian time. There were fluctuations and a fall in sea level at the end of Messinian time. Following that was a major rise in earliest Pliocene then a general regressive signature prevailed into Quaternary time with a number of fluctuations (Hallam 1992). The present-day morphology of the outer fjords along the west coast of Spitsbergen is dominated by cliffs in bedrock or in Quaternary sediments and barrier beaches (Forman, Mann & Gifford 1987). Raised beaches are interpreted as having been formed during a period of rebound subsequent to deglaciation. Raised beaches in most of the fjords are extensive and well preseved. Generally they are tilted by differential postglacial uplift (e.g. Lindner, Marks & Szczesny 1986; Semevskiy 1996; Semevskiy & Shkatov 1996). There is evidence for a modern transgression (Forman et al. 1987): at Ebeltofhamna on the east side of Mitrahalvoya the coffins of seventeenth century whalers are being eroded by the sea from the upper part of a bluff and, on the east side of Mitrahalvoya, the fiver is graded to a base level at least 1 m below mean tide.

Raised beach stratigraphy. A major consideration in Quaternary studies is the detailed stratigraphy afforded in raised beaches that occur along the margins of most fjords in Spitsbergen and Nordaustlandet. Because of post glacial differential uplift the beaches cannot solely be correlated by their height above sea level.

They do however generally contain materials that may allow correlation (e.g. Elton & Baden-Powell 1931; Baden-Powell 1939; Dineley 1954). For biostratigraphic studies the timescale is too short to identify evolutionary changes. But changing environments, of sea temperatures in particular, have been used for correlation. One fortunate fact is the widespread occurrence of drifted pumice derived from Jan Mayen and Icelandic eruptions. A major event appears at around 40 ka BP. Feyling-Hanssen (1955a, b) worked on the marine invertebrate faunas of Billefjorden (mainly bivalves and gastropods) and postulated the sequence for correlation in Spitsbergen and postulated the scheme shown from his fig. 14 (Fig. 21.15). He and Olsson (1968), from five radiocarbon ages, gave approximate correlations with North European climatic stages (Olsson & Blake 1962). Hjort et al. (1995) reported on radiocarbon-dated Mytilus edulis in relation to a marine climatic optimum that corresponds to a Late Holocene sea-level transgression. Feyling-Hanssen & Ulleberg (1984) described a foraminiferal section at Sarsbukta. The lower strata appeared to be Mid-Late Oligocene and then a typical gap before Late Pleistocene (Late Saalian to Eemian) and Holocene deposits which were not disturbed by later glaciation. Blake (1960, 1961) described radiocarbon dating of raisedbeach deposits from inner Murchisonfjorden in Nordaustlandet. Beaches up to 100 m a.s.1, are well preserved and as usual the beach levels rise towards the inner fjords. Radiocarbon determinations on driftwood and whalebones set a limit at 7 ka with a main pumice horizon determined at 4kaBp. Other determinations (Saxicava, Mya and Mytilus) gave ages of 9-10 ka with some shells (Saxicava arctica) estimated to be 3 5 - 4 0 k a old. Blake suggested that the absence of material between 10 and 35ka was the result of more extensive ice cover in that interval. On the other hand, as has been noted, Boulton (1979a) postulated that this interval, between his Weichselian and 'Billefjorden' glacial events was essentially nonglacial in the inner fjords. Forman (1990) comprehensively reviewed the postglacial sealevel history of Svalbard based on scattered published data sets throughout the archipelago, and based mainly on northwestern Spitsbergen. From the 18 curves plotting relative sea level against a time scale going back to 10ka, some even to 12 or 14ka, and, disregarding the different methods of the various authors, the following generalizations may be made.

I

Stratigraphy of Inner Isfjorden (Feyling-Hanssen 1955) Period Sub-recent

Formation Littoral I Sublittoral Lowest terraces

Mytilus terraces

~ 0~0} E o ~ o. ~

"o .o_ ~ ~ ~

correlation

Littoral

l Sublittoral Astarte, Serripes Mytilus edulis

Lower Astarte t. . . . . . .

Upper Astarte

~ E o

terraces

~

Mya terraces

~

~

~ "~ m $ -o "~ -6 .j o

Approximate Characteristic fossils

~

Scattered Mya and Saxiclava

Astarte elliptica Astarte boreafis Heteranomiasquamul~ Cyprina islandica Lithorthamnion Cyprina islandica Zirfaea crispata Littorina littorea

Mya truncata Saxicava arctica Chlamysislandica Mytilus edulis Littorinasaxatilis

Mya truncata Macema calcarea Saxicava arctica

Scattered

Mya truncata and Saxicava arctica

Fig. 21.15. Late Pleistocene stratigraphy of inner Isfjoorden (adapted from Feyling-Hanssen 1955a and Feyling-Hanssen & Olsen 1960).

NEOGENE AND QUATERNARY HISTORY T o w a r d s western Spitsbergen there was a steep fall r o u n d a b o u t 8 or 9 ka Br, generally to a postulated negative sea level at a r o u n d 7 ka to present with some indications of a m i n o r rise in sea level above the present at a b o u t 2 or 3 ka (the ' m i d - H o l o c e n e transgression'). F o r m a n plotted estimates of the rates of emergence in coloured maps showing a m a x i m u m rate 30 m ka -1 in western Oscar II L a n d as well as central a n d eastern Svalbard for the interval 10 to 9 ka. F o r the interval 9 to 8 ka the contours of similar pattern, open to the east, reduce to 10 or 5 m k a -1 and a m a x i m u m of 5 m k a -1 in southern N o r d a u s t l a n d e t . The effect o f the fall in sea level is seen in the strandflats typical of Spitsbergen coasts, not least a r o u n d Oscar II L a n d and Prins Karls F o r l a n d . The mid-Holocene transgression was further documented by FeylingHanssen (1965) in Billefjorden and at Talavera in Barentsoya; Blake (196l) and Hyvgtrinen (1969) in NW Nordaustlandet; Salvigsen (1977, 1978) at Svartknausflya in Nordaustlandet. N o r t h w e s t e r n Spitsbergen is characterized by steep cliffs plunging into the sea w i t h o u t any beach. This c o r n e r of the island, probably with less ice cover to u n b u r d e n , and consequently with a smaller isostatic r e b o u n d , was overtaken by eustatic rise. Conversely the thick ice cover, as postulated for eastern Svalbard, w o u l d on

435

reduction permit the land to rise faster t h a n from the eustatic consequences of global climate amelioration. A general isostatic flexuring of the lithosphere rather than block faulting is inferred. In conclusion, H o l o c e n e Svalbard first uplifted rapidly but at a decreasing rate to the present. Rates of uplift were estimated at southern N o r d a u s t l a n d e t by Salvigsen (1978) thus: 9.5 7 . 5 k a 7.5-5.5ka 5.5-3.5 ka 3.5-1.5ka 1.5-Present

- 2 2 . 5 m m a -1 - 4 . 5 m m a -1 - 7.5 m m a -1 - 2 . 5 m m a -1 - insignificant

B o u l t o n & R h o d e s (1974) correlated raised beaches by four horizons with pumice ( t h o u g h t to have drifted f r o m Jan M a y e n ) in years BP as follows.

Murchisonforden Dun~rbreen Valhallfonna

A

B

C

D

c. 6500 6525 6420

6200

4100 400 4150

2100 2300 2250

Chapter 22 Modern glaciers and climate change JULIAN 22.1 22.2

A. D O W D E S W E L L

Introduction, 436 Modern ice cover of Svalbard, 436

& EVELYN

K. D O W D E S W E L L

22.4.2 Icebergs, 442 22.5

Late Holocene glacial events and chronology, 443

22.2.1 Glacier and ice-cap distribution, 436 22.2.2 Ice mass dimensions, 436

22.5.1 Moraine systems, 443

22.3

22.6.1 Climate records and glacier mass balance, 444 22.6.2 Modelling glacier response to future climate change, 444 22.6.3 The ice-core record of climate change, 445

Geophysical characteristics and ice dynamics, 438

22.3.1 Glacier thermal and hydrological structure, 438 22.3.2 Ice dynamics, surging and fast glacier flow, 441 22.4

Ice-ocean interactions, 442

22.6

Glaciers and climate change, 444

22.4.1 Tidewater glaciers, 442

22.7

22.1

the equilibrium line on Svalbard ice masses from aerial photographs and satellite imagery also shows that the altitude of this line, or zone, above which net accumulation of mass takes place, is lowest in the eastern islands and on the east side of Spitsbergen (Fig. 22.2b). The equilibrium line altitude is highest, at about 800 m, in Andree Land, one of the least heavily glacierized areas of the archipelago.

Introduction

By the start of the Holocene, the decay of the large ice sheet over Svalbard and the Barents Sea region was nearing completion, and glacier ice was approaching its present distribution (Elverhoi et al. 1993; Siegert & Dowdeswell 1995). Throughout most of the last 10 000 years, the extent of glaciers and ice caps over the archipelago has been no greater than that observed today, with the exception of minor readvances in the relatively cold 'Little Ice Age', which terminated at the beginning of the twentieth century. Nonetheless, ice today covers about 62% of the 62 000 km 2 Svalbard archipelago (Fig. 22.1). Svalbard is one of four heavily ice-covered archipelagos in the Eurasian High Arctic; those to the east are Russian Franz Josef Land, Severnaya Zemlya and Novaya Zemlya. The ice cover on each archipelago is a function of topography and the location of each along the strong west-east gradient in climate across the Eurasian Arctic. Svalbard, as the most westerly of the four, is the warmest and receives the highest precipitation. This is due to its proximity to the relatively warm oceanic North Atlantic Drift and to the depression tracks transferring relatively temperate, moist air masses northward through the Norwegian-Greenland Sea. This position at the northernmost limit of both warm water and air masses makes the archipelago and its glaciers very sensitive to changes in atmospheric and ocean circulation. In addition, General Circulation Models (GCMs) predict that any future CO2-induced warming will be most significant at high northern latitudes (Cattle & Thomson 1993). This chapter discusses the distribution and dynamics of the contemporary glaciers and ice caps extending over 36 500km 2 of Svalbard, together with their responses to immediate past and future climate change.

22.2 22.2.1

M o d e r n ice cover o f S v a l b a r d Glacier and ice-cap distribution

The dimensions of ice masses in Svalbard show a trend towards increasing size from west to east across the archipelago (Fig. 22.1). The largest ice caps are those of Austfonna (8120 km 2) and Vestfonna (2510 km 2) on Nordaustlandet, while the 710 km 2 Kvitoya, the most easterly island of Svalbard, is over 99% ice covered (Table 22.1). By contrast, several relatively mountainous parts of Spitsbergen, particularly Nordenski61d Land and Andree Land, have only a limited ice cover (Fig. 22.1). This ice distribution is related to the pattern of precipitation across the archipelago (Fig. 22.2a). The highest precipitation, which falls mainly in solid form, is found in the eastern parts of Svalbard and is related to low pressure areas bringing moisture from the Barents Sea (Hagen et al. 1993). Precipitation is low in the Nordenski61d and Andree Land areas, which are sheltered orographically from precipitation-bearing air masses. Mapping of

Summary and conclusion, 445

22.2.2 Ice mass dimensions

The ice masses on Svalbard vary from small cirque and valley glaciers (10 -1 to 101 km 2) to some of the largest ice caps in the Eurasian Arctic (103 to 104 km2). Hagen et al. (1993) have produced a detailed inventory of the 2229 ice masses of area greater than l km 2 in the archipelago. The analysis was undertaken using the Norsk Polarinstitutt 1 : 100 000 map series of Svalbard which was, in turn, produced from vertical aerial photographs and associated ground control points. The inventory conforms to the standardized criteria set out by the Secretariat of the World Glacier Inventory, and is therefore directly comparable with glacier inventories carried out in many other ice covered regions. The differentiation of the drainage basins and ice divides (analogous to watersheds in hydrology) used to define the area of each ice mass is straightforward for the glaciers and ice fields of Svalbard, where bedrock outcrops are common, but is more difficult for the larger ice caps. Digitally-enhanced Landsat satellite imagery (Fig. 22.3) was used to locate the position of the ice divides on the Nordaustlandet ice caps and, hence, to define the major drainage basins within these ice caps (Dowdeswell & Drewry 1985). The surface elevations of Svalbard ice masses are mapped from aerial photographs for the bulk the archipelago. On the large ice caps of Nordaustlandet, however, too few ground control points are available for accurate height determination. Instead, the corrected ice surface altimetric data derived from airborne radioecho sounding of these ice caps is used (Dowdeswell et al. 1986). Radio-echo sounding at frequencies between 6 and 620MHz has also been used to measure the ice thickness and bedrock Table 22.1. The dimensions of the ice masses on the main islands of Svalbard

Island

Total area (kin2)

Ice-covered area (km2)

Percentage ice-covered

Length of ice cliffs (kin)

Spitsbergen Nordaustlandet Edgeoya Barentsoya Kvitoya Kong Karls Land

39 170 14 997 5160 1298 710 345

21 805 11262 2194 610 705 22

55 75 42 47 99 6

485 305 80 23 105 0

Sources: Dowdeswell (1989); Hagen et al. (1993); Bamber & Dowdeswell (1990).

M O D E R N GLACIERS AND CLIMATE CHANGE

,~,

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.

18~

.

.

.

437

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'

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.

.

.

.

80

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km .t 8 %

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,

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/

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Fig. 22.1. Map of Svalbard showing the distribution of the modern glaciers and ice caps. The island of Kviteya is inset9 Glaciers observed to surge (Section 22.3.2) are shown in black and shading represents areas of bare land not covered by glaciers.

438

CHAPTER 22

elevation of most of the larger ice caps and glaciers on Svalbard (e.g. Macheret & Zhuravlev 1982; Dowdeswell et al. 1984a, 1986; Bamber & Dowdeswell 1990; Hagen & Saetrang 1991; Dowdeswell & Bamber 1995).

a)

r

Examples of 60MHz radio-echo sounding records from Austfonna, the largest ice cap in Svalbard, are given in Fig. 22.4, together with a three-dimensional diagram of this ice cap and the 3400 track-km of radio-echo flight-lines used in its construction (Dowdeswell et al. 1986). The maximum ice thickness on Austfonna is 560m and over 28% of its bed is below present day sea-level. The nature of the substrate underlying Austfonna cannot be inferred directly from the radio-echo sounding. However, periods of ice recession are likely to have been associated with marine sedimentation. Renewed advance is then likely to have occurred over a potentially deformable substratum. Further, marine geological surveys have shown the presence of unlithified sediments in regions recently exposed by retreat of the ice mass (Solheim & Pfirman 1985). Hence, Austfonna probably overlies deformable sediments in at least its marginal regions. The terminal few kilometres of many of the larger tidewater glaciers throughout the archipelago are also grounded below sea level and are likely to have beds of deformable sediments. Some caution is needed in the interpretation of radio-echo sounding records of Svalbard glaciers at U H F frequencies (>300MHz), hoivever. Dowdeswell et al. (1984b) demonstrated that earlier Soviet measurements of ice thickness using 620 MHz equipment consistently underestimated glacier thickness relative to both the 60 MHz and lower frequency radars used by British and Norwegian workers and the few seismic and gravity surveys that existed. This problem is due to the high absorption and scattering of the radar signal as frequency increases. Hagen et al. (1993) therefore incorporated ice thickness measurements at the lower frequencies wherever possible in their inventory of ice-mass dimensions, and derived a volume estimate of about 7000 km 3 for the total contemporary ice cover on Svalbard.

lO0 km

0 t

i

I

22.3

b)

Geophysical characteristics and ice dynamics

300 ?~ 300

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350 350

22.3.1

Glacier thermal and hydrological structure

I

I !

0

,00

200

I

300

/ 300

Fig. 22.2. (a) Map of estimated precipitation (mma -1) over Svalbard. (b) Map of estimated equilibrium line altitude (m above sea level) over Svalbard. (Source: Hagen et al. 1993.)

The characteristic thermal structure of Svalbard glaciers is polythermal (also referred to as sub-polar), where some areas of the ice are at the pressure melting point and other areas are colder (Schytt 1964; Baranowski 1977; Jania 1988). Schytt (1969) described the thermal regime of the ice caps on Nordaustlandet, based on the distribution of shallow temperatures, as an annulus of cold ice surrounding an interior at the pressure melting point. This superficially inverted distribution of internal ice temperatures is accounted for by the significance of the release of latent heat through meltwater refreezing and the formation of superimposed ice on many Svalbard ice masses. Surface meltwater percolates into and refreezes in the snow and firn on the upper part of the ice masses, providing an important source of heat. By contrast, meltwater produced at lower elevations at the ice surface simply runs off over an ice surface which is only permeable via large crevasses and moulins. There is thus no source of latent heat in the glacier ablation area, where ice is also thinner than over much of the accumulation zone. The characteristic thermal structure of cold ice in the ablation zone, often overlying temperate ice, and ice at the pressure melting point in the upper, accumulation zone has been observed at many Svalbard ice masses. Ice temperatures of this general form have been measured using instrumented boreholes and have been inferred from multi-frequency radar data (e.g. Odeg~rd et al. 1992; Jania et al. 1996) and from numerical modelling simulations (Nixon et al. 1985). However, some Svalbard ice masses, especially those which have undergone significant thinning as a result of surge activity, are known to be below the pressure melting temperature throughout (e.g. Dowdeswell et al. 1995). Such thin, cold ice masses often have a very low accumulation area ratio and are in a consistently negative mass balance regime (Section 22.6.1). The hydrological structure of Svalbard ice masses is linked to their thermal regime, and particularly to temperatures close to the

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.

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.

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Fig. 22.3. (a) Landsat Multispectral Scanner satellite image of the Austfonna ice cap, Nordaustlandet, eastern Svalbard (Fig. 22.1). The main ice divides can be identified. The image was acquired on 25 March 1973.(b) Interpretation of ice-cap drainage basins on Nordaustlandet. The box indicates the location of the Landsat image shown in (a).

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r

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v (J 7-

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1

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D I S T A N C E (km)

I

0

Fig. 22.4. Airborne radio-echo sounding data from Austfonna, Nordaustlandet. (a) 60 MHz airborne radio-echo sounding records from Austfonna, Nordaustlandet. IC represents tidewater ice cliffs. (b) Three-dimensional isometric projections of radio-echo derived ice surface, bedrock and ice thickness data. (e) Radio-echo flight-lines used to construct isometric views. The solid lines are flight tracks where bed echoes were identified and dashes represent places where no bed echo was recorded. (Reproduced with permission from Dowdeswell et al. 1986; Dowdeswell 1989.)

bed. In turn, the structure of the basal hydrological system will have implications for glacier flow rates and for the triggering of surge behaviour (Section 22.3.2). Glaciers that are cold throughout, for example the 3km 2 Scott Turnerbreen (R. Hodgkins pers. comm.; Dowdeswell et al. 1995), have a single-component drainage structure. Supraglacial meltwater provides the source, and water routing to the margin is via supraglacial and ice-marginal channels. There is no basal drainage system identifiable from hydrogeochem-

ical analyses of the bulk meltwaters (Hodgkins et al. 1995). Ice velocity is very low and the bulk of the glacier is essentially stagnant. By contrast, glaciers where at least part of the bed is at the pressure melting point, for example the 44 km 2 Finsterwalderbreen (Nixon et al. 1985; R. Odegfird pers. comm.), are more active; Finsterwalderbreen flows at up to 25 m a -1 . In addition, measured velocities on Finsterwalderbreen double during the melt season (Nuttall et al. 1997), and preliminary analyses of time-dependent

MODERN GLACIERS AND CLIMATE CHANGE measurements of the glacier hydrogeochemical signal indicate that a basal drainage system does develop in summer (Wadham et al. 1997).

The dynamic regimes of Svalbard ice masses are diverse, with individual glaciers and ice-cap drainage basins being characterised by 'normal' flow, periodic surge-type behaviour or continuous fast flow (Dowdeswell 1986). Glaciers in the former category tend to flow at a few tens of metres per year and have typically parabolic icesurface profiles (Fig. 22.5a). Fast-flowing glaciers and ice-cap outlets tend to flow continuously at hundreds of metres per year and to have surface profiles which are of low gradient relative to 'normal' flow. The outlet glaciers of southern Vestfonna in Nordaustlandet provide a clear example of fast flowing outlet glaciers separated by ridges of slower moving ice (Fig. 22.6).

i

600-

e

~

,

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Fig. 22.6. The fast-flowing ice cap outlet glaciers on Vestfonna in Nordaustlandet. (a) Location of the satellite image in (c) within Svalbard. (b) Airborne radio-echo sounding profiles, located in (c), across and down the outlet glaciers. (c) Landsat Multispectral Scanner image (acquired on 16 August 1978) of the outlet glaciers. Dashed lines define the border of each outlet glacier, which is identified from a mottled appearance resulting from kilometre-scale ice surface roughness. (Reproduced with permission from Dowdeswell & Collin 1990.)

{V3)

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22.3.2 Ice dynamics, surging and fast glacier flow

a)

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*~"

441

2'0 2'5 30

3's

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Fig. 22.5. Ice-surface profiles and bedrock derived from radio-echo sounding of the ice caps on Nordaustlandet. The solid lines are observed ice surface altitudes and the dashed lines are theoretical parabolic surface profiles. (a) Normal basins, (b) fast-flowing outlets, (e) surge-type basins. (Reproduced with permission from Dowdeswell 1986.) The drainage basins are located in Fig. 22.3b and letter and number identifiers represent the ice cap and drainage basin, respectively. A is Austfonna and V is Vestfonna.

An intermediate ice-dynamic category is provided by ice masses of surge-type, which exhibit cyclical instabilities in the form of short phases of rapid motion (a few months to a few years), punctuating significantly longer periods of quiescence and stagnation (20-200 years) (e.g. Meier & Post, 1969; Raymond 1987). During the active phase, mass is transferred rapidly down-glacier in association with heavy surface crevassing and an advancing surge front (Fig. 22.7). In the quiescent phase, there is net accumulation of mass in an upper 'reservoir area', which thickens and steepens to a critical point, at which fast flow is triggered by a reorganisation of the hydrological system at the ice-bed interface, and associated changes to the geotechnical properties of any soft basal sediments (Clarke et al. 1984; Kamb 1987). The mechanism which triggers glacier surges is, therefore, independent of any direct climatic control. Prior to the active phase, glacier surface profile is steep and, conversely, the surface profile is very flat during early quiescence (Fig. 22.5). Svalbard is one of several regions worldwide where a relatively large number of glaciers and ice caps are known to surge (Fig. 22.1). Others regions include Alaska, the Yukon, Iceland and the Parmirs. Almost 100 Svalbard ice masses have been observed to surge (e.g. Liestol 1969, 1993; Schytt 1969; Dowdeswell et al. 1991; Hagen et al. 1993; Lefauconnier & Hagen 1991). One of the largest surge events observed anywhere was that of Bfftsvellbreen on Nordaustlandet, whose advance around 1936 covered some 600 km 2 of previously unglacierized area (Schytt 1969). A number of recent surges of Svalbard glaciers appear to have an active phase of particularly long duration relative to surges in other regions from which observations are available (Dowdeswell et al. 1991). The quiescent phase of the surge cycle is also relatively long (50-500 years) for the few Svalbard ice masses for which evidence is available. The surge front (Fig. 22.7b) has been observed to propagate down-glacier for between three and ten years on Svalbard ice masses, as compared with less than one to two years elsewhere. Surge velocities in Svalbard are also relatively slow compared with other areas. The transfer of mass from an upper reservoir area to a lower receiving area is, therefore, accomplished over a considerably longer period in Svalbard. The rapidity with which surges terminate also differs between Svalbard and Alaskan glaciers. The surge of

442

CHAPTER 22 iiiiiiiiiiiiiiiiiiiiiiiiii~i~ i .......

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...........

::::: :; ::::~ : :

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Fig. 22.7. Photographs of a surge of Bakaninbreen, Spitsbergen. (a) The heavily crevassed surface of the surge-type glacier during its active phase. (b) The active surge front advancing into stagnant ice. (Reproduced with permission from Dowdeswell et al. 1991.) Usherbreen in Spitsbergen terminated slowly, with a decrease in velocity towards quiescent phase values occurring over several years (Hagen 1987). By contrast, very abrupt surge termination, over only a few days and linked to major changes in basal hydrology, was observed at Variegated and West Fork glaciers in Alaska (Kamb 1987; W. D. Harrison pers. comm.). Such systematic differences in surge duration between Svalbard glaciers and those elsewhere should be a reflection of: (i) the differing rates of operation of basal processes; (ii) the operation of different kinds of basal processes; or (iii) a combination of the above.

22.4 22.4.1

Ice-ocean interactions Tidewater glaciers

Tidewater glaciers (Fig. 22.8), which are ice masses with marine margins grounded below sea level, make up over 1000 km or almost 20% of the coastline of the Svalbard archipelago (Table 22.1; Dowdeswell 1989). Most tidewater glaciers have ice cliffs of only a few hundred to a few thousand metres in length. However, the tidewater margins of Austfonna in Nordaustlandet form an ice cliff of about 130 km in length broken only once by a small rock outcrop (Fig. 22.3b). These terminal ice cliffs provide a significant site of glacier mass loss by iceberg production in addition to any losses by ablation and meltwater runoff. Most tidewater glacier margins exhibit transverse crevassing, indicating that these areas are in longitudinal tension (Hodgkins & Dowdeswell 1994). The crevasses are important in the

iceberg calving process and provide a constraint on the dimensions of the resulting bergs. Hughes (1992) developed a theory of iceberg calving from tidewater glaciers in which calving rate is controlled by bending creep behind the terminal ice cliff, and depends on ice cliff height, forward bending angle, crevasse spacing and water depth. The rate of iceberg calving from tidewater glaciers is also related empirically to water depth (Brown et al. 1982), presumably because buoyancy increases with depth. There is evidence to support this relationship from the small numbers of Svalbard tidewater glaciers for which observations of terminus velocity and water depth immediately offshore are available (Pelto & Warren 1991). The near-terminus velocity and calving rate of Kongsbreen, a tidewater glacier in northwest Spitsbergen, have been measured from high-resolution satellite imagery (Lefauconnier et al. 1994). This tidewater glacier is flowing at up to almost 8 0 0 m a -~ and calving about 0.25 km 3 of icebergs into the adjacent fjord system. Plumes of turbid meltwater upwell from point sources at the base of many tidewater ice cliffs, and are assumed to be derived from a basal hydrological system (e.g. Elverhoi et al. 1980; Pfirman & Solheim 1989; Dowdeswell & Drewry 1989). It is, however, very difficult to measure the discharge of meltwater at these sites. Sedimentation from these meltwater plumes is the dominant influence on marine deposition in fjord locations proximal to tidewater ice cliffs (Elverhoi et al. 1980, 1983).

22.4.2

Icebergs

The icebergs calved from the margins of Svalbard tidewater glaciers and ice caps are varied in form (Fig. 22.9). The dimensions and

MODERN GLACIERS AND CLIMATE CHANGE

Fig. 22.8. The terminus of a Spitsbergen tidewater glacier top; Nordenski61dbreen. Tensional crevasses parallel to the margin are shown, and the glacier is flowing from right to left. Beyond the terminus, to the left of the glacier front, the sea-surface is covered by a layer of shore-fast sea ice. (Source: Dowdeswell 1989.) dynamics of the parent ice mass are likely to affect both the shapes of calved icebergs and their rate of production (Dowdeswell 1989). Tidewater glaciers of a few kilometres in terminus width are found in each of the major fjord systems in Spitsbergen- Hornsund, Van Keulenfjorden, Van Mijenfjorden, Isfjorden, KongsfjordenKrossfjorden, Woodfjorden-Liefdefjorden, and Wijdefjorden. Based on observations in Kongsfjorden (Dowdeswell & Forsberg 1992), each of these fjord systems is likely to be characterised by the production of relatively large numbers of small bergs (width < 10 m) and fewer large icebergs of irregular shape. This statement is supported by: (i) the similarity in ice dynamics between the tidewater glaciers entering these fjord systems and (ii) aerial reconnaissance and photographs of these fjords (see Dowdeswell 1989). Certain ice masses in eastern Svalbard may also produce significant numbers of relatively large (>100 m length) tabular icebergs. This is particularly the case for the long lengths of terminal ice cliffs present around eastern Nordaustlandet and Kvitoya (Dowdeswell 1989). It has also been observed that Negribreen, a tidewater glacier at the north end of Storfjorden, east Spitsbergen, which last surged in 1935-36 (Vinje 1989), has produced a number of tabular icebergs in excess of 100m length since that time (Dowdeswell 1989). Vinje (1989) has also proposed that interannual variability in the occurrence of icebergs in the Barents Sea may be linked with surge activity in eastern Svalbard. The icebergs produced at the ice-ocean interface are important for glacial geological reasons, in addition to their role in glacier mass balance. Where debris is included within them, they form a process of sediment transfer from the terrestrial to the marine environment (Dowdeswell & Dowdeswell 1989). As the icebergs melt, this ice-rafted debris is released and is deposited on the sea floor, often forming characteristic sedimentary structures and facies (Gilbert 1990). If iceberg keels contact the sea floor, scouring and associated sediment reworking also takes place.

443

Fig. 22.9. Photographs of the contrasting morphology of icebergs derived from Svalbard glaciers. (a) A tabular iceberg of about 600 m in length within newly formed sea ice, east of Nordaustlandet (courtesy of D. J. Drewry). (b) Iceberg of irregular shape in a Spitsbergen fjord. The maximum freeboard is about 5 m.

22.5 22.5.1

Late Holocene glacial events and chronology Moraine systems

Fluctuations in the position of glacier termini can reflect changes in climate, through the effects of shifts in temperature and precipitation on glacier mass balance. However, the links between climate and glacier fluctuations are not simple and glacier dynamic factors must also be considered. Ice masses in most areas of the High Arctic have been retreating for much of the twentieth century, whether their margins end on land or in marine waters (Dowdeswell 1995). On Svalbard, aerial photographs acquired at intervals since the 1930s show that many glaciers are in retreat from clearly defined terminal moraine systems, with the exception of those that have surged. Chronological control for the last few hundred years is usually provided by radiocarbon and lichenometric dating methods. Andrb (1986) and Werner (1993) have used calibrated lichen growth curves to show that glaciers retreated from prominent moraine systems in north and northwestern Spitsbergen from about the turn of the century. In a number of areas of Svalbard, the moraine systems marking the end of the 'Little Ice Age' cool period represent the most extensive ice advance during the Holocene (Werner 1993). The analysis of early reports and maps, together with the availability of systematic aerial photography since 1936, shows two typical types of glacier terminus behaviour (see Lefauconnier & Hagen 1991). The first is terminus advance, presumably rapid, associated with the active phase of the surge cycle. The second is a

444

CHAPTER 22

more general retreat from moraine systems probably dating from a Little Ice Age maximum, linked to changing environmental conditions and, in some cases, to stagnation during the quiescent phase of the surge cycle. Prominent moraine ridges, sometimes protruding beyond the line of the coast where tidewater glaciers are present, mark the recent extent of these ice masses. Within Svalbard fjord systems, aerial photographs, expedition charts and lateral moraine sequences indicate that significant tidewater glacier retreat has taken place in the last 100 years or so. For example, the lateral moraines of Lillieh66kbreen, a tidewater glacier in northwest Spitsbergen, were dated using lichenometric methods (Werner 1990), implying retreat from the turn of the century from a maximum Holocene position related to the Little Ice Age climatic cooling. Glacier retreat since the end of the nineteenth century has been between approximately 2 and 3 km for Lillieh66kbreen, and echo sounder profiles of the fjord floor show that the lateral moraines can be traced as submarine terminal moraines across the sea bed (Sexton et al. 1992). Liestol (1976) has made similar observations of submarine moraines in Van Keulenfjorden at the margins of Nathorstbreen.

22.6

Glaciers and climate change

22.6.1

Climate records and glacier mass balance

Meteorological records acquired from western Svalbard since 1911 show an abrupt rise in mean annual air temperature of almost 5~ after about 1920, fluctuating about this higher level since that time (Hanssen-Bauer et al. 1990; Fig. 22.10). This climate change is linked to the termination of the cold Little Ice Age over the North East Atlantic sector in general (Kelly et al. 1982; Grove 1988), with Svalbard representing an end member of particular climatic sensitivity due to its position at the northern extremity of relatively warm ocean currents and depression tracks. The relationship between inputs of mass to glaciers, as snow or refrozen meltwater, and mass loss, in the form of meltwater runoff and iceberg production (for tidewater glaciers), is known as glacier mass balance. If, over a balance year, inputs exceed losses, then an ice mass has a positive balance, and vice versa. However, long time series of glacier mass balance observations are scarce and losses by iceberg calving are very difficult to quantify, restricting mass balance data largely to ice masses ending on land (Dowdeswell et al. 1997). Measurements at a number of Svalbard glaciers from 1950 onwards (Fig. 22.11) demonstrate that mass balances have been

o

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Fig. 22.11. Glacier net mass balance measurements for three Spitsbergen glaciers. Note that, from a total of 45 data points, positive net balances were recorded in only four years. (Reproduced with permission from Hagen & Liestol 1990; Dowdeswell 1995.)

consistently negative (Hagen & Liestol 1990). Reconstructions, based on statistical correlations between climate and glacier mass balance for the period since climate records began, extend this conclusion back to the second decade of this century (Lefauconnier & Hagen 1990). This implies cumulative net losses of mass of the order of tens of metres water equivalent over this period. This is why the bulk of Svalbard glaciers, which were close to their maximum extent for the last 10 000 years at the start of the twentieth century (Hagen & Liestol 1990; Werner 1993), have undergone sustained retreat and thinning since that time (Section 22.5).

22.6.2

Modelling glacier response to future climate change

Modelling the mass balance of Svalbard glaciers using an energy balance approach provides a method of assessing their sensitivity to possible future climatic perturbations (see Oerlemans 1992). The model (Oerlemans 1993), which calculates the components of ice surface energy balance, takes meteorological data, the area distribution with altitude of the ice mass, and parameters defining the global radiation as input values. The mass balance of a glacier surface is expressed as: M = Jyear [ ( 1 - f ) m i n ( 0 ; - B / L ) +

P]dt

(1)

L) o..

v

I--

1

._>

where M is annual mass balance, f is the fraction of meltwater that refreezes instead of running off, B is the energy balance of the surface, L is the latent heat of melting and P is rate of solid precipitation. The energy balance is found from:

2

.-.

..-?.

-6

19Z0

1930

1940

1950

1960

1970

1980

Year

Fig. 22.10. Temperature records from Svalbard for the period since 1912, including both mean annual and mean July values. The data are synthesised from two stations in western Spitsbergen (Isfjord Radio and Svalbard Lufthavn). (Source: Hansen-Bauer et al. 1990).

B = Q(1 - a) +/in + lout -I- Fs --~ F]

(2)

where a is the surface albedo, Q is the shortwave radiation reaching the surface, /in and lout are the incoming and outgoing longwave radiations and Fs and F1 are the sensible and latent heat fluxes. Model results for several Svalbard glaciers, using observed meteorological parameters, yield satisfactory predictions of measured mass balances over a ten year period, and therefore offer an appropriate means of assessing the climate sensitivity of glacier mass balance in the archipelago (Fleming et al. 1997). Average net balances for 1980-1989, predicted using models tuned to the decade's average, were -0.44 and -0.47 m water equivalent for two northwest Spitsbergen glaciers, compared with measured averages of -0.27 and - 0 . 3 6 m . The model was then used to predict the effects of recent climate change on glacier mass balance and equilibrium line altitude. Several climate warming scenarios were input to the model (Fig. 22.12), which predicted a negative shift in net mass balance of 0 . 5 - 0 . 8 m a -1 for each degree of warming (Fleming et al. 1997), depending on the area/elevation

MODERN GLACIERS AND CLIMATE CHANGE 700

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Fig. 22.12. Energy balance model predictions of glacier response to future global warming, calculated for a northwest Spitsbergen glacier. The reference data are predictions of mass balance with altitude for the modern climate, and the other curves are for increases in mean annual temperature of between 1.5 and 4.5~ (Source: Fleming et al. 1997.) distribution of individual glaciers. By contrast, modelling suggested a cooling of about 0.6~ or a precipitation increase of around 23%, would be required to give a zero or slightly positive net mass balance.

,

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,

14oo igoo Time (years AD)

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2000

cores, the interval interpreted to represent from about 1550 to 1920 contains up to 30 40% less refrozen ice layers than that since 1920 (Tarussov 1992). The first half of the sixteenth century is intermediate between these two periods. The melt layer signal from the large ice caps in the Russian archipelago of Severnaya Zemlya indicates a warming trend from about 120-140 years ago, earlier than in Svalbard (Kotlyakov et al. 1989; Tarussov 1992). However, despite some broad agreement, the detailed isotopic and stratigraphic records from individual High Arctic ice cores show high interannual to interdecadal variability, and doubts remain about the chronology of the ice core records so far derived from Svalbard ice masses (Dowdeswell et al. 1990; Tarussov 1992).

22.7 22.6.3

1ooo

Fig. 22.13. Variations in oxygen isotope ratio since AD 1200 for the Lomonosovfonna ice core, Spitsbergen. (Source: Gordiyenko et al. 1981.)

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445

Summary and conclusions

The ice-core record of climate change

Deep ice cores have been obtained from a number of High Arctic ice caps. Where little or no surface melting takes place to complicate core stratigraphy and chemistry, a temporal resolution of 4-1-2 years is possible over the past few centuries (e.g. Bradley 1985). However, in Svalbard, where mean annual temperatures are significantly higher, melting and refreezing effects dominate and chronology is more difficult to establish (e.g. Dowdeswell et al. 1990; Tarussov 1992). Debate over the chronology and climatic significance of the Hoghetta ice core from northeastern Spitsbergen illustrates the problems involved (Fujii et al. 1990; Dowdeswell et al. 1990). Oxygen isotope ratios, which are related to temperature at the time of snow condensation and several complicating factors (Bradley 1985), and the number and thickness of refrozen melt layers, which are proportional to ice surface melting and therefore provide an index of summer warmth (Koerner 1977), have been used as proxies for climate in Arctic ice cores. Some broad similarities are present in oxygen isotopic records from Lomonosovfonna in eastern Spitsbergen (Gordiyenko et al. 1981) and cores from Devon Island, Canada (Paterson et al. 1977), Camp Century in North Greenland (Johnsen et al. 1970) and the Vavilov Ice Dome, Russian Severnaya Zemlya (Kotlyakov et al. 1990). The previous two to three centuries have markedly more negative oxygen isotopic ratios than the twentieth century (Fig. 22.13). The sixteenth century is somewhat warmer than the 1600-1900 period, but isotopic values do not generally approach those of the relatively warmer twentieth century. The recent records of melt layers in Arctic ice cores also show similarities over space, and with the isotopic record. In Svalbard ice

Glaciers and ice caps, the largest up to about 8000 km 2, cover over 62% of Svalbard today. Many of these ice masses reached their maximum Holocene extent only about 100 years ago, immediately prior to the termination of the cold interval known as the Little Ice Age. The Svalbard region is particularly sensitive to climate change because it is positioned at the extreme northward limit of the ocean currents and air masses involved in poleward heat transfer through the North Atlantic. The thinning, terminus retreat and consistently negative mass balance of many modern Svalbard ice masses is a direct response to warming since the turn of the century (Figs 22.10 and 22.11). This warming, marking the end of the Little Ice Age, is usually assumed to be unrelated to anthropogenic effects on atmospheric composition (Bradley 1985). However, predictions of future 'greenhouse' warming will effect the mass balance and the distribution of the glaciers on Svalbard. Energy balance modelling of these effects demonstrates that mass will be lost at an enhanced rate under these circumstances, leading to further thinning and retreat (Fig. 22.12). Such model predictions are made from the baseline of modern climate, and assume that future non-anthropogenic climatic effects will be zero. The ice-core record of climate fluctuations over the last few centuries (Fig. 22.13), and meteorological data collected in Svalbard since 1912 (Fig. 22.10), both show a high interannual and interdecadal variability in the climate signal. Thus, Late Holocene climate has been far from stable, even prior to the impacts of industrial society. This provides an additional uncertainty, whose sign cannot even be specified, to predictions of climate change and its effect on the dimensions and dynamics of Svalbard glaciers and ice caps over the next decades and centuries.

PART 4 A p p e n d i x : E c o n o m i c g e o l o g y : e x p l o r a t i o n f o r coal, oil a n d m i n e r a l s , 449 I n d e x o f place n a m e s , 455

G l o s s a r y o f s t r a t i g r a p h i c n a m e s , 463 R e f e r e n c e s , 477 G e n e r a l I n d e x , 515

Alkahornet, a distinctive landmark on the northwest, entrance to Isfjorden, is formed of early Varanger carbonates. The view is from Trygghamna ('Safe Harbour') with CSE motorboats Salterella and Collenia by the shore, with good anchorage and easy access inland. Photo M. J. Hambrey, CSE (SP. 1561).

Routine journeys to the fjords of north Spitsbergen and Nordaustlandet pass by the rocky coastline of northwest Spitsbergen. Here is a view of Smeerenburgbreen from Smeerenburgfjordenwhich affords some shelter being protected by outer islands. On one of these was Smeerenburg, the principal base for early whaling, hence the Dutch name for 'blubber town'. Photo N. I. Cox, CSE 1989.

The CSE motorboat Salterella in Liefdefjorden looking north towards Erikbreen with largely Devonian rocks in the background unconformably on metamorphic Proterozoic to the left. Photo P. W. Web, CSE 1989.

Access to cliffs and a glacier route (up Hannabreen) often necessitates crossing blocky talus (here Devonian in foreground) and then possibly a pleasanter route up the moraine on to hard glacier ice. Moraine generally affords a useful introduction to the rocks to be traversed along the glacial margin. The dots in the sky are geese training their young to fly in V formation for their migration back to the U K at the end of the summer. Photo W. B. Harland, CSE 1990.

Appendix Economic Geology: Exploration for coal, oil and minerals W. B R I A N 23.1 23.2

HARLAND

Coal, 449 Petroleum, 451

The incentive for most geological exploration has been related to the possibility of mineral wealth. Some has been undertaken by industry, other as a result of national interest. A great deal of academic research, particularly since 1960, has been financed by industry. It is impossible with financial pressures so strong to disentangle the presentation of research as between 'fundamental' and 'applied'. This section, summarizes the explicit search for hydrocarbons (coal and petroleum) and metalliferous and other minerals which in various ways has been alluded to in the preceding chapters. It is not intended as a comprehensive survey.

23.1

Coal

Coal seams crop out extensively in Svalbard and, being conspicuous in cliffs and talus, have been exploited in surface workings for fuel by whalers and hunters from the earliest days. The potential for mining and export and the political implications was increasingly realised from the later years of the Nineteenth Century. Until the status of Spitsbergen and Bjornoya was settled, coal was a political consideration and when the Treaty protected international commercial rights, economic facts slowly displaced political manoeuvring until the present situation where purely commercial considerations hardly make mining coal for export competitive. Coal occurrences may also have a potential for natural gas, possibly with similar competitive limitations with the present perception of offshore resources. Coal, being the only mineral effectively exploited, has focused research on coal-bearing strata. This review treats coal in situ from a stratigraphic-regional viewpoint beginning with the youngest seams. Further discussion in a stratigraphic context can be found in the regional and historical chapters. Hitherto coal has been relatively easy to exploit above sea-level (for bunkers and export) and, within the permafrost zone of mountains, freezing temperatures avoided problems with water. Deep mining would need substantial resources and has been considered seriously perhaps in only one locality, Gipsdalen (Helovnori 1983). Pavlov & Yevdokimova (1996) noted extensive analysis of Svalbard's coals. Perhaps the principal impression is of the burial and local tectonic history. The Early Carboniferous coals of Pyramiden and Bjornoya gave ash rich in A1203. Reserves were estimated at 836 x 106t with 96% represented by gas or coking coals. Of the above 208 x 10 6 t, 138 x 10 6 t and 490 x 106 t of coal reserves are respectively. Early Carboniferous, Barremian and Paleogene. Similarly Yevdokimova (1996, p. 99) noted that Carboniferous (Mississippian) coals derived from lycopsids, selaginellas and pteridospermaphytes whereas Paleogene coals depended on plane, yew, cypress, pine etc. All were classified as humid (see also Yevdokimova 1980; Yevdokimova, Vorokhovskaya & Birukov 1986). Paleogene coal. Oligocene or latest Eocene coals occur in graben sequences on the west coast of Spitsbergen. The Forlandsundet Basin on the east side, especially at Sarsoyra, exposes the Balanuspynten Formation whose Sarsbukta member contains coal and plant fragments defining thin seams of up to 15cm. Thin seams of coal were also recorded in the west by Atkinson (1962) at McVitiepynten. Although there is no prospect of mining coal the several km of such facies may generate significant gas as has been confirmed by the Norsk Polar Navigasjon A/S well at Sarstangen ( P e t r o l e u m E c o n o m i s t 1975).

& ANTHONY 23.3 23.4

M. S P E N C E R

Metalliferous minerals, 453 Non-metalliferous minerals, 454

The Calypsostranda Basin, which is about 4 km along the coast, extends about 700m from the shore. The Skilvika Formation (Livshits 1967; Thiedig et al. 1979), 115.5m of mainly silts and shales with plant remains, contains many thin coal horizons which were the basis of short lived exploitation at Calypsobyen. Seams are mostly only a few cm, but three attained 0.28, 0.46 and 0.65m thickness. The Central Basin is a N - S brachy-syncline of the Van Mijenfjorden Group with six units CB6 to CB1, top to bottom, as described in Chapter 4.2 and ranging from mid-Eocene back to Paleocene. Of the six formations coal has been recorded in CB6, CB3 and CB1, and of these CB1 is by far the most important (e.g. Lyutkevich 1937; Major & Nagy 1972; M a n u m 1956; Pavlov & Panov 1980). The Aspelintoppen Formation (CB6), occurring at the tops of mountains in the middle of the Central Basin, contains thin seams near the base, and below sediments formed in a mobile environment with slumping related to the uplifting West Spitsbergen Orogen. No seams thicker than 30 cm have been recorded. The Grumantbyen (Sarkofagen) Formation (CB3) contains a seam of a few cm and was recorded by Croxton & Pickton (1976) in the Berzeliusdalen area; Livshits (1965) noted a 1 m seam in the Barentsburg region. The opportunity at Grumantbyen was exploited (e.g. Lyutkevich 1937b; Shkola et al. 1980). Exploration of Heer Land (Pavlov & Panov 1980) and Nordenski61d Land (Croxton & Pickton 1976) has not led to exploitation. The Paleocene Firkanten Formation (CB1) is the principal source of coal in Svalbard, being mined at Longyearbyen, Barentsburg and Sveagruva. Major & Nagy (1972) named five seams (from the top) Askeladden, Svarteper, Longyear, Todalen and Svea. They pointed out that the Todalen is typically less than 60 cm and the Askeladden seam though well developed has a high sulphur content (Major et al. 1992). From Longyearbyen mines have successively exploited the seams often high in the mountains, in successive blocks between the valleys with numbered mines, old numbers 1 and 2 occur on the mountain sides at the opening of Longyeardalen. New numbered mines 1 (and '1') on both sides of Adventdalen half way up the valley; No. 3 (the latest to be reworked) due south of Longyear/Svalbard Lufthavn at Hotellneset; No. 4 near the head of Longyeardalen; No. 5 on the south flank of Endalen to the southeast; No. 6 due east at the nose of Karlundhfjellet between Todalen and Bolterdalen and the presently working No. 7 east of Bolterdalen 11 km ESE of Longyearbyen. The later mines up Adventdalen and No. 3 were served by road after the cable system was discontinued. In each case the coal was stored through the winter at Hotellneset and shipped out in the summer. These mines have been practically exhausted and the only viable coal mine is at Sveagruva, also in the Firkanten Formation, where a 5 m seam presents opposite problems in mining (Pewe et al. 1981; Myrvang & Utsi 1989). With so well serviced a settlement at the capital Longyearbyen and with shipping difficult at Sveagruva, the project for a road between the two settlements was under consideration; miners fly each 10 days. Coal mining even with present-day efficiency, is hardly self-supporting in Svalbard. Similarly the mine at Barentsburg (Kotlukov 1936) has exhausted the original concession and a further concession has been leased to the south. The economic case without political support may be difficult to maintain. The mine at Grumantbyen also in the Firkanten Formation was abandoned after the Second World War when most mines were destroyed to prevent their use by the other side. (For the history of this mine see Samoilivich 1913, 1920; Samoilivich et al. 1927; and a more recent exploration borehole - Shkola et al. 1980.)

450

APPENDIX

The Ny-Alesund coalfield. This had been worked from the surface since whaling days with early exploration claims. Systematic mining developed between about 1917 to 1962 when the mine was finally abandoned after the worst of a series of accidents, even though significant extensions of the mine had been planned. The Ny-Alesund coalfield is shown in Fig. 9.3 where the NyAlesund Subgroup comprises two formations. The upper (Broggerbreen) formation with the Bayelva Member has four mined seams, and below it the Leirhaugen Member has the Agnes Otelie seam at the base. The lower (Kongsfjorden) formation divides into two barren sandstones and conglomerate members above an unconformity. Below this is the Kolhaugen Member with a number of seams. The Ny-Alesund Subgroup certainly correlates with the Paleocene Firkanten Formation in the Central Basin and possibly the upper part with the overlying Basilika Formation. Indeed, although currently separated from the Central Basin by the Broggerhalvoya fold and thrust front, in pre-Eocene time it appears to have been continuous and correspondingly is classified with the Van Mijenfjorden Group. The seams vary greatly in thickness even within the c. 5 km 2. explored in five boreholes and many pits up to 1928. Orvin's account of the coalfield is the best available. Midboe worked on the mine records after that until closure of the mine, but his work has not yet been published except for extracts (used here) from SKS reports (Dallmann et al. 1996). Orvin (1934) recorded in detail sections, analyses and volume estimates of every available excavation (pp. 85-161) from which the following is abstracted. KB2 is roofed by the Kapp Starostin thrust. It could be equivalent to KB1. ?8 m separation from the KBI Seam which is too thin to be economically interesting. 30 m below is the Ragnhild Seam, which was thin and cut by the Kapp Starostin overthrust and not effectively worked. 36 m below this the Josefine Seam, extended up to 135m beneath the overriding thrust. Up to 2 m undivided coal was worked. 20 m below this is the Agnes-Otelie, which was largely worked out and was cut by the overriding thrust surface. Totalling nearly 2 m of coal it was divided by up to 0.4 m of sandstone. Separated from the seam below by 70-80 m is the Advoeat Seam. This seam is divided by as many as 5 shale partings, is variable and proved unworkable economically. Sofle Seam varies in thickness and with shale partings, the coal itself totalling up to 3 m. 8-12m below is the lowest seam. This is the Ester Seam, which is the most important in the coalfield of more uniform thickness, of up to 2-3 m with thin shale partings and greatest area. It rests on the 'Bottom shale' (Triassic Vardebukta Formation).

Cretaceous coal. The Helvetiafjellet Formation, of probable Barremian age, is the only Cretaceous unit with a record of coal. The formation crops out throughout the rim of the Central Basin and commonly shows traces of coal in the typical sandstone facies of the upper (Glitrefjellet) member. The only records of significant exploitation refer to the outcrops east of Adventfjorden, c. 90 cm, mainly at Advent City (now a ruin) and Moskushamna. Hoel (1929) had reported reserves of 1500 x 106t of l m seams within 600 m of the surface (above and below sea-level) but from the investigation of Smith & Pickton (1976) in the mountains between Adventdalen and Sassendalen, including the eponymous mountains, it appears that Advent City mined the best seam between 1904 and 1908. At the mine is a lower seam of 40cm separated by 9 cm of shale from an upper seam of 50 cm. Generally, however, the seams are further divided and, with an ash content of 14% to more than 19%, have proved uneconomic. To the north of Isfjorden, at Bohemanneset, the last effort to mine Cretaceous coal between 1920 and 1921 was made. Coal below sea-level was noted by Hoel at Grumantbyen (Harland, Pickton & Wright 1976).

Jurassic coal was reported earlier (Stevenson 1905) but has not been noted recently.

Trassic coal. Thin coals have been reported from the Late Triassic (?Carnian) De Geerdalen Formation, of sandy deltaic facies (Klubov, Aleksejeva & Drosdova 1967). Klubov (1964, 1965) had mapped coal in this unit at Wilhelmoya, Barentsoya and Edgeoya, and Pchelina & Panov (1966) noted coals around Wichebukta and upper Sassendalen. It appears that one seam from 0.10 to 0.40 m is widespread and, with allochthonous plant material, now has a high carbon content. No exploitation has been attempted (Harland, Pickton & Wright 1976).

Early Carboniferous (Mississippian) coal. Coal measure 'Kulm' or 'Culm' facies are typical of the Billefjorden Group both in central Spitsbergen and Bjornoya. They have been actively mined at Pyramiden and Tunheim respectively (Dibner 1986; Antevs & Nathorst 1917). In Bjornoya, of the three (Ursa Sandstone facies) members of the Roedvika Formation, the lower (Vesalstranda) member is of Famennian age, and the middle (Kapp Levin) and upper (Tunheim) members are Tournaisian. Only the Tunheim member coals have been mined (at Tunheim), but coals are also found in the upper 60 m of the Vesalstranda Member. At Tunheim coal is exposed in the cliffs of the east coast and of the many seams only one or two are workable. Mining ceased in 1925 for combined reasons of divided seams, difficult loading from a cliff top and low prices internationally (Horn & Orvin 1928). Of the many seams in the lower (Vesalstranda) member all are too thin so that their likely wide extent underground has no economic interest (Gjelberg 1978; Pavlov et al. 1983). In the Billefjorden area there is undoubtedly extensive Mississippian coal for which a potential may exist in Gipsdalen (Helovuori 1983). This would be the only substantial prospect in a coalfield beneath sea-level. Coal is exposed near Brucebyen south of Adolfbukta, but the principal outcrop has been extensively mined at Pyramiden where thick seams have been claimed (Lyutkevich 1937b). The area has been described by Cutbill, Henderson & Wright (1976). In the succession (at Birger Johnsonfjellet), with revised classification and nomenclature, the original Svenbreen Formation has been divided with the upper red beds which are included in a new Hultberget Formation within the overlying Gipsdalen Group. Thus in the Billefjorden Group, the (upper) Mumien Formation shows at least three coal seams in the upper (Birger Johnsonfjellet) member largely of carbonaceous shales. The lower (Sporehogda) member is of coarser sandstone and conglomerate facies with plant remains, but no coal. The (lower) Horbyebreen Formation has at least three more seams of poor coal near the top of the Hoelbreen Member, and at least one seam near its base. The underlying Triungen Member is coarser grained without coal.

Devonian coal. Svalbard may claim two of the few occurrences of Devonian coal anywhere. Already noted are the seams of Famennian age in Bjornoya which are of no economic interest (e.g. Gjelberg 1978). Similarly in Mimerdalen, up-stream from Pyramiden, is the late Devonian 'brown coal'-type outcrop (Horn 1941; Vogt 1941). It is not known to have been worked, and if there were a slight potential it is too near to Pyramiden to compete.

Sturtian 'anthracite'. Sturtian is taken here (from Harland et al. 1990) as the period preceding Vendian and possibly extending back to about 800 Ma. The formation in question is the H6ferpynten Formation of Hornsund which is most likely coeval with the Akademikerbreen Formation of Ny Friesland and which might have an age of around 750 • 50 Ma. It was surprising, therefore, when Birkenmajer, Frankiewicz & Wagner (1992) reported 'Late Proterozoic anthracite coals'. These are not seams, but high-grade hydrocarbons appearing to be metamorphosed organic material in irregular voids or vugs in dolostone. Two occurrences were noted (i) in the Andvika Member

APPENDIX: ECONOMIC GEOLOGY (dolostone with cherts) of the H6ferpynten Formation at H6ferpynten south of Hornsund and (ii) in a similar dolostone at Krakken just east of Vestre Torellbreen and possibly related to the (?coeval) Dunoyane Formation. The organic material has been interpreted according to coal routines as of algal origin in a lagoonal setting. It is clearly a bituminous substance which indicates the most extreme alteration suggested at 500~ and pressure of 20 000 MPa. There are multiphase graphite crystallites. Graphitic phyllites and schists of presumed Vendian age are not uncommon and the implication is for genesis of petroleum in late Proterozoic carbonates which are abundant in Svalbard (Danyushevskaya e t al. 1970). Other references are included below.

451

Stratigraphic. Paleogene: Manum & Throndsen (1978); Throndsen (1982). Mesozoic: Dypvik (1980); Mork & Bjoroy (1984); Embry (1989); Krajewski (1989). Cretaceous-Jurassic: Bjoroy & Vigran (1980); Bjoroy et al. (1979);

Dypvik (1985); Gramberg & Ronkina (1988); Hvoslef et al. (1986); Zakharov & Kulibakina (1988). Triassic: Bjoroy & Hall (1983); Bjoroy et al. (1979,1980); Dypvik (1979); Falcon (1928); Forsberg & Bjoroy (1983); Throndsen (1979). Permian-Carboniferous: Cameron & Goodarzi (1992); Emery (1989); Kano (1992); Lonoy (1988); Staff & Wedekind (1910); Stemmerik et al. (1994); Stemmerik & Larsen (1993). Neoproterozoic: Danyushevskaya et al. (1970). Bjoroy (1977); Bjoroy & Vigran (1979); Bjoroy (1980, 1983, 1987); Dypvik (1980); Hvoslef et al. (1986); Isaksen (1996); Krajewski (1989); Schou et al. (1984); Voytov et al. (1979, 1981). Geochemical/composition.

et al.

Birkenmajer (1992); Dypvik (1979); Hughes et al. (1976); Manum et al. (1977); Pedersen (1979); Throndsen (1979), (1982); Zakharov & Kulibakina (1994). Subsurface environment.

Adadurov (1927); Ahlmann (1941) Andersson (1917); Berr (1914); Breuer & Zimmelund (1922); Burov (1919); De Geer (1899, 1012); Deutscher Seefischerei-Verein (1900); Dillner (1913); Gothan (1937); Harland et al. (1976); H6gbom (1913); Hoel (1916, 1920, 1922b, c, 1924, 1925, 1938, 1966); Horn (1928, 1930); Kotlukov (1933); Lyutkevich (1937); Mewins (1900, 1901); Odelberg (1916); Ohlson (1979); Olsen (1929); Orheim (1982); Pavlov & Evdokimova (1996); Reusch (1913); Simmerbach (1917, 1919); Zaytzev (1917, 1921). General, historical, political, economic.

Brugmans (1987); Cadell (1920); Hanoa (1993); Hoel (1922a); Mansfield (1919); Misnik & Belousov (1983); Myrvang & Utsi (1989); Orheim (1979); Pewe et al. (1981); Statistiske Centalbyrft (1916); Werenskiold & Oftedahl (1922); Mining.

Horn (1929); Pavlov (1964, 1065); Yevdoki(1986); Yevdokimova (1996).

Geochemical/composition.

mova

et al.

Abdullah et al. (1988); Horn (1929); Hughes (1976); Manure & Throndsen (1978); Pavlov et al. (1980).

Environment and coalification. et al.

Exploration.

Bugge et

Comparisons elsewhere.

al.

et al.

(1995);

Dalland (1979), Breach & Rowan (1992); Dengo & Rossland (1992); Ronnevik & Jacobsen (1984); Spencer et al. (1984); Sverdrup & Bjorlykke (1992).

Stuctural constraints.

Exploration. In Barents shelf (not Svalbard). General: Bergsager (1986); Nagy (1965, 1968); Pedersen (1977); Spencer (1984); Winsnes (1975); Yevdokimova (1980). Regional: Bjoroy et al. (1980, 1983, 1987); Dalland (1979); Heafford (1992); King (1964); Ronnevik (1981, 1983); Ulmishek (1985). Potential: Bergsager (1986); Bleie et al. (1982); Bro et al. (1991); Dalland (1979); Halbouty (1986); Harland (1969a); Leith et al. (1992); Nottvedt et al. (1992); Nys~ether & Saeboee (1979); Oljedirektoratet (1996); Rasmussen et al. (1995); Wells: Bjoroy et al. (1981); Bugge et al. (1990); Gramberg et al. (1985); Kornfield (1965); Leythaeuser et al. (1983); Shkola et al. (1980); Shvarts (1985).

(1990); Orheim (1982).

C a m e r o n & Goodanzi (1992); Dibner & Krylova

(1963).

23.2

Hydrocarbon occurrences. Bakken et al. (1994/5); Lammers Max & Lowrie (1993); Voytov et al. (1979, 1981).

Petroleum

Confirmed by 17 wells Svalbard has been disappointing in the search for petroleum and for various reasons, not least the tack until recently of subsurface structural information and the lower porosities in reservoirs that might otherwise have been promising. This results partly from the Eocene orogeny in the west. Mesozoic latitudes reached about 70~ by the end of Triassic time so that later biogenic productivity may not have been encouraging, though higher atmospheric CO2 may have obtained (Fig. 23.2). On the other hand Svalbard comprises a varied sedimentary sequence that is commonly regarded as an exposed sample of typical successions beneath the Barents Sea. There is reason for this in that Svalbard may be regarded as the uptilted corner of the Barents shelf (e.g. Harland 1969) resulting from a reversal of mantle cooling and contraction at that corner which approximates the ultimate fission that developed into the Arctic and Greenland Sea basins. The petroleum potential of the cover sequence (Carboniferous through Paleogene) has been mentioned in passing in the foregoing chapters and is summarized in Spencer's contribution below. The basement as defined in this work is not generally considered in this respect. Early Paleozoic strata containing carbonates have generally suffered extensive Caledonian tectogenesis. Where in west Spitsbergen they have escaped such intense tectonism the facies are not so rich in carbonates. Late Proterozoic successions in the east especially are rich in carbonate facies with significant but uneconomic biogenic components and traces of bitumen often mentioned in Russian literature. The following works relevant to petroleum and petroleum geology have been taken from the selected bibliography and arranged alphabetically.

P e t r o l e u m e x p l o r a t i o n (A. M. S).

Exploration is conducted under the rules for mining set out in the Svalbard Treaty of 1920, with applicants 'staking' licence areas each up to 10 km 2. These are then registered with the Bergmester for Svalbard who regulates all exploration activity, but utilizes the Norwegian Petroleum Directorate for resource assessment and for technical assessment of the safety aspects of drilling. Exploration licence areas have durations of five years: they are retained by undertaking geological studies, seismic surveys or by drilling. In contrast to the Norwegian Shelf,

r-.,k~,mhukenl "~:K,Jadehukenil $8~~ rstarlgen

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.

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................. t+s9

.

lllRar

"

t"

~ Hopen7

. fla.

, ............. ++e+

Fig. 23.1. Plot of major wells in Spitsbergen.

.

12+~

'II~I0

7+:

7."

".";'"

ms.broon11 ~ ....

' . . . . . . ~.4o' ' '

Hoponl 124~

452

APPENDIX

Table 23.1. Deep well data for Svalbard Well

Location

Lat/ Long

Date

Company

1 Gronfjorden

Nordenski61d Land

1963 to 1964

NPN

2 Ishogda I*

Van Mijenfjorden

1965 to 1966

Amoseas

3 Bellsund

Berzeliusdalen

1967 to 1981

NPN

405

4 Hopen It

Hopen

1971

Fina

908

5 Raddedalent

Edgeoya

1972

Total

2823

6 Plurdalent

Edgeoya

1972

Fina

2351

7 Kvadehuken I

Broggerhalvoya

1972 to 1973

NPN

479

8 Hopen IIt

Hopen

1973

Fina

2840

9 Kvadehuken II

Broggerhalvoya

77 57 34 14 20 36 77 50 22 15 58 00 77 47 00 14 46 00 76 26 57 25 01 45 77 54 10 22 41 50 77 44 33 21 50 00 78 57 03 11 23 23 76 41 15 25 28 00 78 55 32 11 33 11 78 43 36 11 28 40 78 07 00 15 02 00 76 52 30 17 05 30 76 52 31 17 05 38 77 49 57 15 11 15 77 49 57 15 11 15 78 03 28 16 56 31 78 06 52 14 43 38

1973 to 1974

NPN

394

1974

NPN

1114

1974 to 1975

Trust Arktikugol

3180

1976 to 1977

NPN

1987 to 1 9 8 8

Tundra/Polargas

2337

1985

Trust Arktikugol

2481

1988 to 1989

Trust Arktikugol

2352

1991

Norsk Hydro/SNSK

2315

1994

SNSK

10 Sarstangen

Forlandsrevet

11 Colesbukta*

Nordenski61d Land

12 Tromsobreen I

Haketangen

13 Tromsobreen II~

Haketangen

14 Vassdalen II*

Van Mijenfjorden

15 Vassdalen III*

Van Mijenfjorden

16 Reindalspasset I* 17 Kapp Laila I*

Nordenski61d Land

Total depth (m) 972 3304

990

504

Age: at surface at TD Early Cretaceous ? Paleogene ? Triassic ? Jurassic Triassic Triassic Permian ? Carboniferous Triassic ? Carboniferous ? Permo-Carboniferous ? Triassic Carboniferous Permian ?Carboniferous Paleogene ? Paleogene ? Early Cretaceous ? Early Cretaceous ? Paleogene ? Paleogene Triassic Early Cretaceous Carboniferous Paleogene Early Cretaceous

Data from NPD Annual Reports and Nottvedt et al. (1993, fig.7); NPN, Norsk Polarnavigasjon; SNSK. Store Norske Spitsbergen Kulkompani. * Minor shows of oil or gas encountered in well. t Wells discussed in Chapter 5 sections 7 8 and 9. Tested minor gas from Permian carbonates.

there are no rules allowing the release of well information, which is thus held privately by the licensing companies. Seventeen deep exploration wells (Fig. 23.1) have been drilled over the period 1963 to 1994 without encountering commercial hydrocarbons, but little information on their stratigraphy or fluid content has been made public. In the period 1984 to 1992 seismic surveys were conducted in the Central Spitsbergen Basin: comprising about 1000km on land and glaciers and a further 1500 km in the fiords (see Nottvedt et al. 1993, fig. 5). Some lines and structural information from these seismic surveys have been published (Nottvedt et al. 1993; Eiken 1994). Table 23.1 summarizes the deep well data on Svalbard. Only the last two wells in Table 23.1 date from after the acquisition of seismic surveys in their areas. Of the earlier wells only Ishogda 1 Raddedalen and perhaps Plurdalen are located on closures mapped at the surface. Seismic data have since shown that Ishogda 1 is positioned to the side of the subsurface closure (N~ttvedt et al. 1992). Most of the other wells are located in monoclinal or synclinal areas where a closed trapping structure is probably absent (Gronfjorden 1, Bellsund 1, Hopen, Vassdalen) or in an area where the subsurface structure is unknown (Sarstangen). Few of the wells have been drilled on certain closures. This may be the main explanation for their lack of success, with only one well testing minor quantities of gas and a few others having shows of gas or oil. This also implies that there have been few valid tests of the petroleum prospectivity of the region.

Nottvedt et al. (1992) have reviewed the petroleum geology of the Central Spitsbergen Basin, which with its thick sedimentary sequence is probably the area of Svalbard with the best petroleum prospectivity. Potential reservoir beds, both sandstones and carbonates, occur there in every System from Carboniferous to Paleogene. Generally speaking, reservoir quality in sandstones is poor in West Spitsbergen, due to quartz cementation, and gradually improves towards east Spitsbergen and the eastern islands. The principal, widespread potential source rocks are the Triassic and Jurassic marine shales (Botneheia, Barentsoya and Janusfjellet formations), each of which can generate oil and gas (Fig. A2). The maximum burial of these source rocks was achieved in late Eocene times and subsequent regional uplift of 2-3 km probably stopped generation. Maturities at Triassic level now range from gas to the oil generation zone (Mork & Bjoroy 1984, fig. 6) with an overall decreasing trend towards the east. Any future hydrocarbon finds here are most likely to be in Mesozoic reservoirs in pre-Tertiary structures that have remained intact during Paleogene compression and Neogene uplift, or in Paleogene compressional structures. Comprehensive surveys of the whole Norwegian Continental Shelf with respect to (a) petroleum discoveries and (b) petroleum resources were published by the Norwegian Petroleum Directorate (Berge 1997a, b). These authoritative works place the Svalbard exploration in relation to the whole Norwegian context and in turn in a global perspective.

APPENDIX: ECONOMIC GEOLOGY N ALASKA

MACKENZIE DELTA

S V E R D R U P BASIN

SVALBARD

453

I S O U T HSHELF BARENTS

TROMSOFLAKET [

I

1

TERTIARY- PALEOCEINIE :

I

MAASTRICHTIAN

iPRINCE C R E E K

CAE~ANIAN I< J

SANTONIAN CONIACIAN TURONIAN

0') ~)

CENOMANIAN

o

uJ

O

ALBIAN

I=

O

CAROLINEFJELLET

,~pnA.

>.

MOUNT GOODB,K~GH

BARREMIAN

er

HAUTERIV|AN

!

VALANGINIAN

m

~ KIMMERIOGIAN

m

"J ..I O

~ N I A N

<[ I .~ ~! ~1

UPPER

0XFOROIAN

BAJOCUm AALENIAN TOARCIAN PLIENSBACHtAN

>" Ir

WILHELMOYA

ul

N ~

w

['[ W -I O

~

CARNIAN LADINIAN AN~AN

i

SPATHIAN

j

GRIESBACHIAN

,~i

All; ]; {r;Vill I r:~ ;l :[,]1]

swr.~N

LIMESTONE

SHALE,SILTSTONE

: 1 1 OMM

~

SANDSTONE-DOMINATED

Fig. 23.2. Mesozoic petroleum source-rocks of the Arctic. OMM, organic-rich marine mudrocks. Reproduced with permission from Leith et al. (1993), Mesozoic hydrocarbon source rocks of the Arctic region, p. 3 in Arctic Geology and Petroleum Potential, Elsevier.

23.3

Metalliferous minerals

Sulphide minerals in particular have attracted the attention of geologists and mining companies mainly for their economic potential which has turned out, with minor exceptions, to be nil. Their occurrence is significant in that they are all recorded in one broad zone, as conveniently summarized by Flood (1969), in basement rocks along the western side of the West Spitsbergen Orogen (Fig 3.5.5). Further detail was provided by Kieres & Peistrzynski (1992), Czerny (1992a, b,c) and Wojciechowski (1964). Mention has been made of these deposits in their stratigraphic context in the regional chapters (9, 10 &l 1). Because of differences of opinion as to the age of mineralisation it would have been clumsy to treat the matter successively in four possibly relevant historical chapters and so the general discussion is summarised here. With few exceptions the host rocks are Precambrian carbonates. This has led to the opinion of Precambrian paragenesis (Birkenmajer & Wojciechowski 1964). Also most occurrences fall within the Paleogene West Spitsbergen Orogen (e.g Siggerud 1962). This led Hjelle (1962) to define a Tertiary age, citing a possible occurrence in Western Nordenski61d Land of sulphides in the Carboniferous cover to the basement. The restriction of sulphide mineral concentrates to the broad zone which satisfies these two hypotheses is not an accident of exploration. Metamorphic terranes in Northwest Spitsbergen, in Ny Friesland and in Nordaustlandet have been searched not least for their mineral content and without significant success. The hypothesis is put forward here that the distribution of these occurrences is related to the composition of the deeper basement (within the crust

and/or the lithosphere), and that were such basement available in the other areas, with extrusive granitic intrusions, it would have showed, possibly in their aureoles. The reason why such basement was not general throughout Spitsbergen may well be related to the foregoing composite terrane hypothesis for Spitsbergen. In short, the Western Terrane almost coincides with the sulphide occurrences which onlap marginally to the east. If that terrane originated north of Greenland it contrasted with the two other provinces of north eastern and central eastern Greenland. This hypothesis might be supported by a survey of mineral occurrences around eastern and northern Greenland and Ellesmere Island, but not disproved. The literature is not adequate for testing because of interest mainly on economic concentrations which need to be considerable for Arctic exploitation (Miles & Wright 1978). This terrane hypothesis is almost, but not quite, indifferent to the age of mineralisation in the surface exposures. A Paleogene age is favoured because of the structural circumstances of the occurrences. It could be argued that the final docking of the terranes in pre-Carboniferous time with Late Devonian transpression and compression tightened up the sinistral shear zones. The general dextral strike-slip Paleogene regime, in addition to generating its own faults, may have reworked and reopened the earlier faults which only brought forth the metalliferous minerals from appropriate deep basement. A little diffusion or tectonic transport east of the fault zone would account for the few adjacent occurrences there. It is conjectured that this mineralized zone was not part of the Caledonides. Even before Ordovician tectonization the zone had suffered, say Grenvillian, and still earlier orogeny.

454

APPENDIX

Extensive Russian investigations in Svalbard resulted in detailed chemical analysis of many rocks encountered for both hydrocarbon and metalliferous potential. Abstracts of previously confidential reports gave some convenient summaries (Krasil'shchikov 1996). Some conclusions are noted here. Turchenko et al. (1996a, b) recorded chalcopyrite in the Northwest corner of Spitsbergen as well as other well known occurrences. In another abstract (Turchenko et al. 1996, p. 95) other mineral occurrences were recorded and were classified into (i) siderophile (ii) chalcophile and (iii) lithophile groups. (i) Skarn iron formations were noted at Magdalenefjorden and Magnethogda; iron-titaniun-vanadiun in gabbroids of Ny Friesland and Chamberlindalen; copper-nickel in peridotites of Chamberlindalen and Jurassic-Cretaceous dolerites of Dickson Land; chromite (in ultrabasic rocks of Oscar II Land). Exogenic goethite-hematite in laterites of Oscar II Land, silicate nickel in Kaffioyra and Sarsoyra and vein siderite at Daudmannsoyra. Siggerud (1962) reported an iron occurrence at Farmhamna in Oscar II Land. (ii) Barite-lead-zinc in Bjornoya; lead~inc in Revdalen, Andvika, Kapp Mineral and Kapp Petermann, all the foregoing in veins. Stratiform occurrences were zinc-chalcopyrite, lead-zinc carbonate in western Nordenski61d Land and Oscar II Land; bornite-chalcocite volcanogenic, and chalcopyrite metamorphogenic at Bockfjorden; metasomatic arsenic-nickel at St Jonsfjorden. Other occurrences were also recorded. Makar'ev et al. (1996, p.97) reported a variety of results including: 'the occurrences of gold sulphide ores, as replacements, were found in the central part of the west coast of Oscar II Land. The mineral composition of the ores, high metal (primary gold) content, and apparent 'gold size' suggest a chance of discovering endogenic and exogenic gold occurrences in further prospecting'. This gold occurrence appears to be related to the shear zone at Kaffioyra and Sarsoya (Ohta, Krasil'shchikov et al. 1995) discussed in Chapters 9 and 12. These sheared occurrences were interpreted here as by Ohta et al. as deriving from the Lovliebreen basic volcanic rocks of Oscar II land. The shear zone of the Kongsfjorden-Hansbreen Fault might be the best prospect for gold. Many of the metalliferous occurrences along the west coast of Spitsbergen are associated with basic volcanic rocks which are correlated in this work (also Harland, Hambrey & Waddams 1993) as early Varanger

(Vendian) and not as much older (e.g. Mesoproterozoic of Ohta et al.). They all belong to the western terranes with a common basement. Uranium and thorium were investigated in the black shale of the Janusfjellet Subgroup (Dypvik & Bue 1984). The Cambridge group drilled superficially for traces of uranium in western Dickson Land without success (e.g. Wright & Henderson 1976). Earlier reports include: Robert (1840-1850), Durochez (1850), Holtedahl (1912) and Werenskiold (1919).

23.4

Non-metalliferous minerals

Only high-value materials, easy to load a n d transport, are likely to be of e c o n o m i c interest w h i c h virtually rules Svalbard out o f c o m m e r c i a l consideration. Sulphates in the f o r m o f g y p s u m and anhydrite are a b u n d a n t and easily accessible, especially in the E b b a d a l e n F o r m a t i o n in Billefjorden. See especially Cutbill & Challinor (1965), Holliday (1966, 1967) a n d J o h a n n e s s o n & Steel (1981). A n abortive mine was started in Skansbukta, Billefjorden. Phosphorite has been considered over a long period, especially Triassic concretions in the Sassendalen G r o u p further south at Svenskehuset, off Billefjorden, 6 k m E N E of K a p p Thordsen, where a m i n i n g party perished in the winter 1882-3. F u r t h e r references include Bugge (1922) and E 1 - K a m m a r & Nysa~ther (1980). Jurassic p h o s p h o r i t e concretions have been described by Backstr6m & N a g y (1985). Marble as a decorative stone was the subject of a failed enterprise attempting to m i n e it at L o n d o n on B l o m s t r a n d h a l v o y a , but was f o u n d to be too jointed. ( N o r t h e r n Exploration C o m p a n y 1913; Siggerud 1963; O h l s o n 1979). Barite was m i n e d in Bjornoya, yielding 75 tons in 1926 ( H o r n & Orvin 1928). Early Paleogene bentonites were described by Dypvik & N a g y (1979) a n d a discussion of mineral waters m a y be of interest (Postnov 1983). River gravels, a virtually renewable resource, are used for road construction.

Index of place names Compiled by ANDERSON

L. M.

This section presents a list of the principal place names used throughout the book. Spellings have been checked against the entries in The Place Names of Svalbard (NP/Skrifter Nos 80 and 112, 1991), covering standardized place names up to 1955, further names have been derived from more recent published topographic maps. Place names of geological interest are located on figures throughout the book and are indicated here by associated figure numbers. Entries in italics are referenced to a regional chapter (4-11) but not located on a figure. The list represents a large selection of those names that are referred to in the geological literature for Svalbard. The spelling in this list, if there be a conflict between the name in the text and a figure, should be preferred. Early stratigraphic names do not necessarily follow the form of the current place names; see the following stratigraphic glossary and index.

Aavatsmarkbreen, 1.7, 9.1 Abeloya, 1.2 Aberdeenflya, 9.1 Adlersparrefjorden, 6.1 Adolfbreen, 21.6 Adolfbukta, 7.1 Adriabukta, 10.1, 20.8b Adventdalen, 4.4 Adventdalen sheet C9, 1.11 Adventfjorden, 1.2, 4.4 Agardhbukta, 1.2, 4.4, 18.1 Agardhdalen, 4.4 Agardhfjellet, 4.4 Agardhfjellet sheet D9, 1.11 Ahlmannfjellet, 9.1 Ahlstrandodden, 18.1, 20.8b Aitkenodden, 9.1 Akademikerbreen, 7.1 Akseloya, 1.2, 10.1, 18.1 Alasdairhornet, 9 Albert Land, 1.3 Albertbreen, 8.4 ,&lbreen, 7.1 Aldousbreen, 5.3, 6.1, 22.6 Alexanderfjellet, 9.1 Alfred Larsentoppen, 9 Alfredfjellet, 11.3 Alkhornet, 1.4, 9.1 Alryggen, 7.1 Amsterdamoya, 8.1 Amundsenbreen, 10.1 Andr6e Land, 1.3 Andr6eneset, 6.1 Andvika, 10 Angellfjellet, 10 Ankerfjella, 9.1 Anna Sofiebreen, 9 Annaberget, 20.8b Antarcticbogen, 9.1 Antarcticfjellet, 1.4, 11.3, 14.2 Antoniabreen, 10.1, 20.8b Apebreen, 8.4 Ariekammen, 10.10 Arctowskifjellet, 4, 5 Arkfjellet, 10 Arlabreen, 8.4 Armstolen, 10 Arnesenodden, 5.6, 18.7 Asbestodden, 10.4 .&sgfirdfonna, 7.1 .&sg~trdfonna sheet C5, 1.11 Asg~rdsreia, 7.1 Aspelintoppen, 4.2 Asvindalen, 16.8 Atomfjella, 1.4, 7.1 Augustabukta, 5.3 Aulrabben, 10 Aurdalskampen, 10 Aurdalen, 10

Austerbogen, 4, l0 Austfjorden, 1.2 Austfjorden sheet C6, I. 11 Austflya, 9.1 Austfonna, 1.7 Austfonna sheet F4, 1.11 Austjokeltinden, 18.7 Austre Broggerbreane, 9 Austre Torellbreen, 1.7, 10.1 Ayerfjorden, 8.4 Backaberget, 6 Backlundtoppen, 1.4, 7.1 Bakaninbreen, 4 B~kvelvet, 20.8b Balanuspynten, 9.9 Balderfonna, 1.7 Balfourfjellet, 9.1 Balliolbreen, 7.1 Bangenhuk, 1.4, 7.1 Bardebreen, 9.1 Barentsburg, 1.2, 10.1 Barentsfjellet, 1.4, 9.1 Barentsjokulen, 1.7 Barentsjokulen sheet E8, 1.11 Barentsoya, 1.2 Basisodden, 6, 7 Basilika, 4.2, 20.8b Bassisletta, 7.1 Bdtodden, 4 Battfjellet, 4.2 Bautaen, 10.10, 20.8b Bayelva, 9 Beachflya, 9 Bellsund, 1.2, 10.1 Bellsundbanken, 1.7 Belvederetoppen, 20.8b Ben Nevis, 8.4 Bendefjellet, 4.5, 20.8b Berglibreen, 7.1 Bergmannshatten, 7 Bergnova, 10 Bergskardet, 10 Bergstr6modden, 6.1 Bernerberget, 20.8b Berrheia sheet F9, 1.11 Bertilryggen, 4.9, 9.1, 18.1 Berzeliustdalen, 3 Berzeliustinden, 1.4, 10.1, 20.8b Bessho, 20.8b Bettybukta, 10.1 Beverlysundet, 6 Billefjorden, 1.2, 4.10 Billefjorden sheet C8, 1.11 Birger Johnsonfjellet, 4.10 Biskayerfonna, 8.7 Biskayerhuken, 1.4, 8.1, 8.7 Bivrastfonna, 1.7 Bjornbogen, 5 Bjornbreen, 10.1

Bjorndalen, 4 Bjornnesholmen, 7.1 Bjornsletta, 5.17 Bjornoybanken, 1.5, 11.1 Bjornoya, 1.2 Bjornoya sheet D20, 1.11 Bjornoyrenna, 1.5 Bjornsonfjellet, 4.2 Bladegga, 10 Bl~fjella, 5.17 Blaho, 20.8b Bl~revbreen, 5.2, 7.1 Bldstertoppen, 10 Bleikfjellet, 7.1 Blomstrandhalvoya, 1.4, 8.1, 9.1 Bockfjorden, 8.1, 21.6 Bodleybreen, 6.1, 22.6 Bodleybukta, 5.3, 6.1 Bodylevskyhogda, 20.8b Bogegga, 9.1 Bogevika, 11.3 Bogstranda, 10.10 Bohemanflya, 1.4, 4.8, 9.1 Bohemanneset, 4.8, 9.1 Bohryggen, 7.1 Bolterdalen, 3 Boltodden, 4.5 Borebreen, 1.7, 9.1, 20.8b B6rrebreen, 8 Borebukta, 9.1 Botnedalen, 10 Botnehaugen, 8 Botneheia, 4.9, 18.1 Botniahalvoya, 1.4, 6.1 Botnvika, 6.1 Bottfjellet, 7.1 Braemfjellet, 20.8b Braganzav~tgen sheet C10, 1.11 Bragebreen, 6.1 Brageneset, 6.1 Br~svellbreen, 1.7 Br~svellbreen sheet F6, 1.11 Bratteggdalen, 10 Bravaisberget, 10.1, 18.1 Bravaisknatten, 10 Bravaisodden, 10 Brdvika, 6 Bredichinryggen, 10.1 Bredsdorffberget, 8, was Wijkberget Breibogen, 1.2, 8.1 Breidfjellet, 7.1 Breikampen, 18.7 Breineset, 10.1 Breinesflya, 10.1 Brenmenfjorden, 6 Brennevinsfjorden, 1.2 Brennkollen, 7.1 Brentskardhaugen, 4.4, 18.7 Brepollen, 10.1, 20.8b Brevassfjellet, 10

456 Broggerfjellet, 9.1 Broggerhalvoya, 4.12, 17.7 Broggertinden, 20.8b Brucebukta, 9.1 Brucebyen, 4.10 Buchananhalvoya, 8.4 Buchananisen, 9.1 Bullbreen, 9.1, 14.2, 14.6 Bulltinden, 14.6 Bulmanfjellet, 8 Bumerangkammen, 7.1 Bungebreen, 10.1, 18.7 Bfinsow Land, 1.3 Burgerbukta, 10.1, 20.8b Cadellfjellet, 4.10 Caiusbreen, 4 Caltexfjellet, 4, 5 Calypsobyen, 10 Calypsostranda, 10.1 Cambreen, 7.1 Cambridgebreen, 7.1 Camp Morton, 10.1 Campbellryggen, 1.4 Camryggen, 7.1 Carolinefjellet, 4.4, 19.11 Carronelva, 4.10 Cavendishryggen, 7.1 Celsiusberget, 6.3 Centralen, 9.1 Ceresfjellet, 7.1 Chamberlindalen, 10.1 Chansjinfjellet, 4 Charapovfjellet, 5.2 Charitonowhogda, 20.8b Charlesbreen, 9.1, 20.8b Cheopsfjellet, 4 Chermisideoya, 6.1 Christophersenfjellet, 20.8b Cholmfjellet, 4.5, 20.8b Chomjakovbreen, 20.8b Chydeniusbreen, 1.7 Citadellet, 4.10 Claravdgen, 6 Claus Andersenfjellet, 20.8b Colesbukta, 1.2, 4.8, 10.1 Colesdalen, 1.7 Collethogda, 4.12, 9.1 Collindadalen, 4 Comfortlessbreen, 1.7, 9.1, 13.2 Condevintoppen, 20.8b Conwaybreen, 9.1 Conwayjokelen, 7.1 Conwaytoppen, 9.1 Cookbreen, 7.1 Copper Camp, 9 Coraholmen, 9.1 Curie-Sklodowskafjellet, 20.8b Dahlbreen, 1.7, 9.1 Dahltoppen, 9 Dalkjegla, 19.11 Dalmoya, 19.11 Dalslandfjella, 20.8b Danskoya, 8.1 Daudbjornfjellet, 20.8b Daudbjornpynten, 4.7 Daudmannsodden, 1.4, 9.1 Daudmannsoyra, 9.1 Davidsonpynten, 9.1 De Geerdalen, 18.1 De Geerfjellet, 1.4 De Veerhogda, 6 Deilegga, 13.2 Deltabreen sheet F11, 1.11

PLACE NAMES Deltadalen, 18.1 Deltaneset, 4 Depotodden, 6.1 Depotoya, 4 Devikfjellet, 9.1, 20.8b Diabaspynten, 10.1 Diabasodden, 4.4 Diabastangen, 10 Diademet, 9.1 Dickson Land, 1.3 Dicksondalen, 1.7 Dicksonfjorden, 1.2 Dicksonfjorden sheet C7, 1.11 Digerfonna, 1.7 Dirksodden, 7.1 Ditlovtoppen, 7.1 Djupvatnet, 11.3 Doddsfjellet, 9.1 Doktorbreen, 1.7 Domen, 4.4 Dordalen, 10 Doveneset, 6 Dovrefjell, 8 Dracoisen, 7.1, 13.2 Draken, 7.1 Drevbreen, 10.1, 18.1, 20.8b Drevfjellet, 20.8b Dronbreen, 4 Dronningfjella, 9.1 Duckwitzbreen, 4.9, 18.1 Dumskolten, 4, 10 Dunderbukta, 10.1 Dunderdalen, 10.1, 13.2 Dundrabeisen, 10.4 Dun~rbreen, 1.7, 7.1 Dun6rfjellet, 1.4, 5.6 Dunoyane, 10.1, 12.6 Dusken, 10 Duvebreen, 6.1 Duvefjorden, 1.2, 6.1 Duvefjorden sheet F3, 1.11 Dyrdalen, 1.7 Ebaelva, 4 Ebbabreen, 4 Ebbadalen, 4.10 Ebeltofthamna, 8 Eddingtonryggen, 7.1 Edfjellet, 20.8b Edgeoya, 1.2 Edgeoyjokulen, 1.7 Edinburghbreen, 7.1 Efuglvika, 11.3 Eggetoppen, 10 Eggtinden, 10 Eholmen, 20.8b Eidembreen, 1.7, 9.1 Eidempynten, 9.1 Eidsvollfjellet sheet B6, 1.11 Eimfellebreane, 10 Eimfjellet, 12.1 Einherjane, 7.1 Einsteinfjellet, 7.1 Einvola, 20.8b Eistraryggen, 4.4, 18.7 Ekkoknausane, 7 Ekmanfjellet, 9.1, 20.8b Ekmanfjorden, 1.2, 9.1 Ekstremhuken, 6.1 Elatidesniveau, 4.1 Elbobreen, 7.1 Elisebreen, 9.1 Ellasjoen, 11.3 Ellevepiggane, 4, 5

Elsabreen, 4 Eltonbreen, 5.3, 6.1 Elvdalfjellet, 9.1 Elveflya, 10.1 Endalen, 4.2 Engadinerberget, 20.8b Engelskbukta, 1.2, 9.1 Enpiggen, 7.1 Eolusletta, 7.1 Eplet, 7.1 Erdmanflya, 4.8, 9.1 Erdmannbreen, 20.8b Erdmannodden, 9.1 Eremitten, 5.2 Ericabreen, 5.3 Erikbreen, 8.4 Eroshetta, 7.1 Eskolabreen, 12.1 Esmarkbreen, 1.7, 9.1, 20.8b Estheriahaugen, 8 Etonbreen, 1.7, 5.3, 6.1 Evabreen, 8.4 Evensenhamna, 11.3 Evjebukta, 11.3 Exilfjellet, 9.1 Fakse glaciers, 7 FaksevS.gen, 7.1 Falunfjellet, 9.1 Fannypynten, 10.1, 13.2 Fannytoppen, 10.10 Fantastiquebreen, 7.1 Farmhamna, 9.1 Farmsundet, 9.1 Farwoodtoppen, 20.8b Feiringfjellet, 9.1 Femmilsjoen, 1.4, 7.1 Ferdinandbreen, 9 Ferrierfjellet, 7.1 Ferskvassbukta, 9.1 Festningen, 4.1, 10.1 Festningsskjoeret, 4.1 Festningsodden, 4.1 Finlayfjellet, 4.10 Finneset, 4 Finnlandryggen, 7 Finnlandveggen, 1.4, 7.1 Finsterwalderbreen, 4.6, 20.8b Firlingane, 20.8b Fisherlaguna, 9 Fiskeklofta, 4 Fiskeknatten, 4 Fl~en, 7.1 Flakfjellet, 10 F15tan, 7.4 Flatbreen, 10.1, 20.8b Flathaugen, 20.8b Flatoyrdalen, 7.1 Flatsalen, 18.1 Fleksurfjellet, 4 Flinthornet, 4 Flogtoppane, 10 Floraberget, 6.3 Flowerdalen, 18.7 Floykalven, 10.4 Foldaksla, 10 Folddalen, 10 Foldtinden, 10 Fonndalen, 6 Fonnkampen, 20.8b Fonnryggen, 4.6 Fordnutane, 10.4 Forgbladodden, 20.8b Forkastingsdalen, 20.8b

PLACE NAMES Forkdalen, 1.7 Fortet, 4.10 Forlandsletta, 9.1 Forlandsundet, 1.2, 9.1 Formidablebreen, 7.1 Forsetekollen, 7.1 Forstebreen, 1.7 Foswincklenuten, 20.8b Fotkollen, 8 Foynoya sheet G2, 1.11 Framnes, 11.3 Fr~enkelryggen, 8.4 Fr~enkeltoppen, 8.4 Franklinfjellet, 6 Franklinsundet, 1.2, 6.1 Frazerbreen, 5.3, 6.1 Freemansundet sheet E9, 1.11 Fridtjovbreen, 1.7, 4.8, 10.1 Friedrichbreen, 21.6 Friherrefjella, 20.8b Frysjaodden, 4.2 Fuglefjellet, 11.3 Fuglehuken, 9.1 Fugleodden, 11.3 Fulmarberget, 7.1 Furystakken, 7.1

Gaffelbreen, 9.1 Gaimardtoppen, 10.4 Gallerbreen, 7.1 Galoistoppen, 7.1 Gangpasset, 10 Garwoodtoppen, 9.1, 20.8b Gdsbreen, 10 G~shamna, 10.1, 10.10, 13.2 Gavltinden, 9 Geddesflya, 9 Gedeonovfjellet, 20.8b Geebreen, 7 Geikebreane, 9.1 Generalfjella, 8.1 Geografryggen, 20.8b Geologryggen, 20.8b Germaniahalvoya, 8 Gerritbreen, 4.10 Gerritelva, 4.10 Gestricklandkammen, 9.1 Gideanoyfjellet, 4.7 Gilsonryggen, 4.2 Gimterbreen, 6.1 Gipsdalen, 1.7 Gipshuken, 1.4, 4.10 Gipsonryggen, Gi~everneset, 5.3 Gjelsvikfjellet, 8 Gjerstadtfjellet, 9.1, 20.8b Glasgowbreen, 7.1 Glimhetta, 20.8b Glintbreen, 7.1 Glitnefonna, 1.7 Glitrefjellet, 4.4 Gn~lberget, 10.10 GoO'sbreen, 10 Goldschmidtfjella, 20.8b Golitsynfjellet, 4 Gonvillebreen, 4 Goosbukta, 6 Gorge Valley (see Kluftdalen) Gotiahalvoya, 1.4, 6.1 Gotiahalvoya sheet D4, 1.11 Gottwaldhogda, 6 Gottytoppen, 19.14 GrShuken, 1.4, 8.1, 16.1

Grdkallen, 10 Grdkammen, 4 Grampianfjella, 1.4, 9.1 Grdnutane, 10 Gr~sdalen, 20.8b Gravsjoen, 10 Grensenfjellet, 9.1 Griegfjellet, 20.8b Grimaldibukta, 9.1 Grimfjellet, 20.8b Grinakertoppane, 9.1, 20.8b Grondalen, 1.7, 10.1 Gronfjorden, 1.2, 10.1 Gronfjordenbreane, 1.7 Gronhorgdalen, 16.8 Gronsteinodden, 10 Gropbreen, 7.1 Grossfjellet, 7.1 Grumantbyen, 1.2 Grumantdahl, 4 Grunningen, 11.3 Grusdievbreen, 7.1 Guldalen, 5 Guldalen sheet E 10, 1.11 Gulfaksebreen, 7.1 Gullichsenfjellet, 10 Gunnar Knudsenfjella, 9 Gunvorbukta, 7.1 Gustav Adolf Land, 1.3 Gustav Adolf Land sheet E5, 1.11 Gustav V Land, 1.3 Gustavfjellet, 1.4 Gyld6noyane, 6.1

Haakenbreen, 1.4 Haakentoppen, 9.1 Haakon VII Land, 1.3 Hahnfjella, 5 Haitanna, 4, 10 Haketangen, 4.7, 10.1 Halgsmarka, 9.6 Hallandkamen, 4 Hallwylfjellet, 19.11 Halvdandalen, 8 Halvdanpiggen, 8.1 Hamarbreen, 9.1 Hambergbreen, 20.8b Hambergbukta, 1.2, 4.5 Hambergfjellet, 11.3 Hamnetangen, 9.1 Hannabreen, 8.4 Hansbreen, 1.7, 10.1, 10.10 Hansoya, 6 Hansteenfjellet, 6 Hansvika, 10.1 H~oya sheet El3, 1.11 Haraldknattane, 8 Hdrbardbreen, 6 Hardiefjellet, 9.1 H~rfagrehaugen, 5.7 Harkerbreen, 7.1 Harlandisen, 7.1 Haukebukta, 9.1 Haussvatnet, 11.3 Havkollen, 19.11 Havsnes, 9.1 Heclahuken, 1.4, 7.1 Hedgehogfjellet, 20.8b Hedgehogfonna, 10 Heemskerckneset, 9.1 Heer Land, 1.3 Heerfjellet, 20.8b Heerodden, 4

457 Heia, 7.1 Heifonna, 7.1 Heimberget, 20.8b Heimbreen, 20.8b Heimfjella, 20.8b Heimfjellhumpane, 20.8b Hellefonna, 1.7 Hellhornet, 20.8b Hellwaldfjellet, 1.4 Helsinglandryggen, 9.1 Helsinkibreen, 7.1 Helvetiafjellet, 1.4, 4.4, 19.11 Henschenodden, 9.1 Hergesellfjella, 9.1 Hermansenoya, 9.1 Hermelinberget, 10 Herwighamna, 11.3 Hessbreen, 20.8b Hesteskoholmen, 8.4 Hetta, 20.8b Himkovtoppen, 5.2 Hinlopenbreen, 1.7, 7.1 Hinlopenbreen sheet D7, 1.11 Hinlopenrenna, 1.7 Hinlopenstretet, 1.2 Hobethvatnet, 11.3 Hdgkollen, 8 Hoelbreen, 4.10 Hoethalvoya, 1.4 H6ferpynten, 10.1, 12.6 H6geloftet, 8.4 Hogsterbreen, 10.1 Hohenlohefjellet, 10.10 Hollendardalen, 4.2 Hollertoppen, 19.11 Holmboeodden, 6.1 Holmbreen, 4.5 Holmesletfjella, 9 Holmesletflya, 9.1 Holmgardfjellet, 4.4, 18.7 Holmstr6mbreen, 1.7, 9.1 Holmstr6moyra, 9.1 Holmvatnet, 11.3 Holtafjella, 9.1 Holtedahlfonna, 1.7, 9.1 Hopen, 1.2 Hopen sheet G14, 1.11 Hopenbanken, 11.1 Hopendjupet, 11.1 H6rbyebreen, 4.10 Hornb~ebukta, 9.1 Hornbreen, 1.7, 10.1 Hornemantoppen, 1.4, 8.1 Hornnes, 9.1 Hornodden, 6.1 Hornstullodden, 10 Hornsund, 1.2, 10.1 Hornsundbanken, 1.7 Hornsundjupet, 11.1 Hornsundneset, 1.4, 10.1 Hornsundtind, 1.4 Hornvika, 11.3 Hotellneset, 3 Hovtinden, 20.8b Hudsonodden, 6.1 Hugindalen, 17.7 Hultberget, 4.10 Humpvarden, 4 Humpvarrier, 4.6 Hunnberget, 6 Hydrografbreen, 14.6 Hyperite Point, see Diabasodden Hyrnebreen, 10.10, 20.8b Hyrnefjellet, 4.6, 10.1, 10.10, 20.8b

458 Idabreen, 8.4 Idabukta, 8.4 Idunbreen, 6.1 Idunneset, 5.3, 6.1, 22.6 Idunfjellet, 5.3 Indre Russoya, 6 Infanten, 17.7 Infantfonna, 9.1 Ingeborgfjellet, 10.1, 20.8b Ingebrigtsenbukta, 10 Ingedjupet, 11.1 Inglefieldbukta, 4.5 Ingstadsegga, 7.1 Innkjegla, 4 Innvika, 6.1 Instrumentberget, 7.1 Irvinefjellet, 7.1 Isachsenfonna, 1.7, 8.1 Isbjornhamna, 1.2, 10.1, 12.1, 12.6 Isbukta, 1.2, 4.7, 10.1 Isdomen sheet G5, 1.11 Isfjellbukta, 10.1 Isfjordbanken, 1.7 Isfjorden, 1.2 Isfjorden sheet B9, 1.11 Isfjordflya, 9 Isfjordrenna, 1.7 Ishogda, 4.4 Isingfjellet, 20.8b Isispynten, 1.4 Isispynten sheet G4, 1.11 Isjebyskovfjellet, 10 Iskantelva, 10 Iskletten, 18.1 Islova, 10 Ispynten, 10.1 Isrundringen, 6.1 lsryggen, 10 Isrypebreen, 9.1, 20.8b Isskiltoppane, 20.8b Isungbreen, 20.8b Iversenfjellet, 1.4, 5.17, 18.1 Ivorytoppen, 7.1 Jacobpynten, 6 Ja'derindalen, 4 J6derinfjorden, 4 James I Land, 1.3 Janssonbreen, 20.8b Janusfjellet, 4.4 Jarnbreen, 10 Jemptlandryggen, 9.1 Jens Erikfjellet, 10 Jeppeberget, 5 Jessiefjellet, 9.1 Johan Hjorlfjellet, 5.17 Johansenfjellet, 9.1 John Rossbukta, 9.1 Johnsenberget, 1.4 Jorgenfjellet, 9.1 Jotunfonna, 4, 8 Julhogda, 10 K.K. Roysa, 20.8b Kaffioyra, 9.1 Kaldbukta, 10.1 Kaldneset, 9.1 Kalven, 11.3 Kamkrona, 10 Kamtoppane, 20.8b Kaosfjellet, 18.1 Kapitol, 4.12, 17.7 Kapp Agot, 11.3 Kapp ,~kerhielm, 5.7

PLACE NAMES Kapp Altmann, 5.7 Kapp Berg, l0 Kapp Bergesen, 11.3 Kapp Bjorset, 10.1 Kapp Borthen, 10.1 Kapp Breusing, 6 Kapp Bruun, 6.1 Kapp Dufferin, 4.4 Kapp Dun+r, 11.3 Kapp Dufva, 5.7 Kapp Elisabeth, 11.3 Kapp Fanshawe, 6.1 Kapp Forsberg, 11.3 Kapp Graarud, 9.1 Kapp Hammerfest, 5.6 Kapp Hanna, 11.3 Kapp Hansteen, 6.1 Kapp Harry, 11.3 Kapp Heer, 11.3 Kapp Johannesen, 4.9, 18.1 Kapp K~tre, 11.3 Kapp Kjeldsen, 21.6 Kapp Kjellstr6m, 11.3 Kapp Koburg, 5.7, 18.1 Kapp Koldewey, 6 Kapp Kolthoff, 11.3 Kapp Lady, 6.1 Kapp Laura, 6.1 Kapp Lee, 1.4, 18.1 Kapp Leigh Smith, 6.1 Kapp Levin, 11.3 Kapp Lindhagen, 6.1 Kapp Linn6, 1.2, 10.1 Kapp Lord, 6.1 Kapp Lov~n, 6.1 Kapp Lyell, 1.4, 10.1 Kapp Malmgren, 11.3 Kapp Maria, 11.3 Kapp Martin, 1.4, 10.1 Kapp Mineral, 10.1 Kapp Mitra, 1.4, 8.1 Kapp Nordenski61d, 11.3 Kapp Olsen, 11.3 Kapp Oscar, 5.7 Kapp Payer sheet E7, 1.11 Kapp Platen, 1.4, 6.1 Kapp Raverstein, 6 Kapp Ruth, 11.3 Kapp Scania, 9.1 Kapp Sietoe, 9.1 Kapp Sparre (= Sparreneset), 6 Kapp Starostin, 4.1, 18.1 Kapp Thor, 5 Kapp Thordsen, 18.1 Kapp Toscana, 18.1 Kapp Walter, 5.6 Kapp Wiessenfels, 5.6 Kapp Wrede, 6.1 Kapp Ziehen, 1.4 Karentoppen, 4 Karl XII Oyane, 6.1 Karlundhfjellet, 3 Karlsbreen, 21.6 Kartdalen, 8 Keilhaufjellet, 4.7 Keltiefjellet, 8, 16 Kikutodden, 4.7, 10.1 Kilodden, 4 Kinamurbreen, 4 Kinanderfjellet, 4 Kingbreen, 7.1 Kinnefjellet, 9.1 Kinockstr6mfjorden, 8.4 Kirtonryggen, 7.1, 14.2

Kistefjellet, 1.4 Kicerfjellet, 9 Kjeglefjella, 1.4 Kjellstr6mdalen, 1.7, 4.4, 4.5 Kjerulfbreen, 20.8b Kj61berget, 19~11 Kjolen, 5.6 Klackbergbukta, 6.3 Klampen, 9 Klausbreen, 4 Kleivdalen, 10 Klementievfjellet, 19.14 Kluftdalen 'Gorge Valley', 7.1, 13.2 Knivodden, 9 Knorringfjellet, 18.7 Knulten, 20.8b Kobbebukta, 11.3 Koefoedodden, 5.17 Kolbukta, 11.3 Kolhamna, 9 Kolhaugen, 9 Kollerbreen, 8 Kollerfjellet, 5.17 Kolosseum, 4.12, 9.1 Kolthoffberget, 4.2 Kolvebekken, 4 Komarovfjellet, 4.12, 17.7 Kong Karls Land, 1.2 Konglomeratfjellet, 10.1, 13.2 Konglomeratodden, 8.4 Konglomeratryggen, 8.4 Kongressdalen, 10 Kongressfjellet, 4.9, 18.1 Kongressvatnet, 4 Kongsbreen, 9.1 Kongsfjorden, 1.2 Kongsfjorden sheet A7, 1.11 Kongsfjordrenna, 1.7 Kongsoya, 1.2 Kongsoya sheet H7, 1.11 Kongsvegen, 1.7 Kongsvegpasset, 9.1 Kongsvegs~ta, 9.1 Konowbreen, 9.1 Kontaktberget, 6.3 Kopernikusfjellet, 20.8b Kortbreen, 7.1 Kostinskifjellet, 19.11 Kovalskifjella, 20.8b Krakken, 3 Kr~emerpynten, 6.1 Krcevefjellet, 4 Krefftberget, 5 Kregnestoppen, 9.1 Kroghfjellet, 4 Krokfjellet, 9.1 Krokoya, 6 Krokvatnet, 11.3 Kronebreen, 1.7, 9.1 Krongleisen, 7.1 Krossfjorden, 1.2 Krossfjorden sheet A6, 1.11 Krossoya, 6.1 Krosspynten, 7.1, 8.1 Kruseryggen, 20.8b Krygernuten, 20.8b Krympefjellet, 20.8b Kfikenthalfjellet, 5.6 Kulmdalen, 4 Kulmodden, 9 Kulmstranda, 10 Kvadehuken, 1.4, 9.1 Kvadehuksletta, 9.1 Kvaevefjellet, 4.8

PLACE NAMES Kvalbreen, 1.7 Kvalrossbukta, 11.3 Kvalfangarbreen, 10 Kvalfinnen, 20.8b Kvalpynten, 1.4 Kvalpyntfjellet, 18.1 Kvalpyntfonna sheet E11, 1.11 Kvalvgtgen, 1.2, 4.5 Kvalvhgen sheet C 11, 1.11 Kveitbola, 11.1 Kvislodden, 10 Kvitbreen, 5.2, 7.1 Kvitoya, 1.1, 1.2 Kvitaya sheet J3, 1.11 Kvitoyjokulen, 1.7 Kviveodden, 10 Lady Franklinfjorden, 1.2, 6.1 Ldgkollane, 4 L~tgnesbukta, 10.1 Lgtgneset, 10.1 Lgtgnesflya, 10 L~gnesrabbane, 10.1 L~goya, 1.2, 6.1 Lagunefjellet, 20.8b Lagunepynten, 7.1 Laksvatnet, 11.3 Landnordingsvika, 11.3 Langesporden, 6 Langfjellet, 7.1 Langgrunnodden, 6.1 Langleiken, 20.8b Langrundisen, 5.6 Langryggs~ta, 20.8b Langeoya, 6 Laplacetoppen, 7.1 Laponiafjellet, 6, 10 Laponiahalvoya, 1.4, 6.1 Lappbreen, 9 Lappdalen, 9.1, 9.6, 20.8b Lapworthtoppen, 20.8b Lardyfjellet, 4.4, 19.14 Larstoppen, 20.8b L~bedevfjellet, 10 Leefjellet, 9.1 Lefjellet, 20.8b Leighbreen, 1.7 Leighbreen sheet G3, 1.11 Leinbreen, 20.8b Leinryggen, 20.8b Leinstranda, 20.8b Leirhaugen, 9 Lemstr6mfjellet, 4.10, 7.1 Lerneroyane, 8.1 Lexfjellet, 9.1 Lidelva, 10 Lidfjellet, 4.7 Liefdefjorden, 1.2, 8.1 Liljevalchfjellet, 19.11 Lillieh66kbreen, 1.7 Lilljeborgfjellet, 8.4 Lindhagenbukta, 6.1 Lindstr6mdalen, 4.4 Linn6dalen, 20.8b Linnbfjella, 10.1 Linnbvatnet, 10.1, 10.8 Lognedalen, 10.4 Lokeryggen, 7.1 Lomberget, 5 Lomfjordhalvoya, 1.4 Lomfjordhalvoya sheet D5, 1.11 Lomfjorden, 1.2 Lomonosovfonna, 1.7 Lomvatnet, 11.3

London, 8.1 Longna, 10 Longnedalen, 10 Longstaffbreen, 7.1 Longyearbyen, 1.2, 4.10 Longyeardalen, 3 Louiseberget, 4 Lov+nberget, 5.2 Lov+noyane, 8.1, 9.1 Lovenskioldfonna, 9.1 Lov6nvatnet, 20.8b Lovetanna, 10 Lovliebreen, 9 Loyningdalen, 8 Luciakammen, 1.4, 10.1, 10.10, 20.8b Luciapynten, 10 Lulefjellet, 9 Lunckevika, 11.3 Lundbohmfjellet, 9.6 Lygna, 11.3 Lykta, 1.4 Lyngebreen, 10 Lyngefjellet, 5.17, 18.1 Lysefjellet, 10 Lysingen, 11.3 MacDonaldryggen, 7.1 Magdalanefjorden, 1.2, 8.1 Magdalanefjorden sheet A5, 1.11 Magdalenafjellet, 7.1 Magnethagda, 10.1, 12.1 Mgtkerholmen, 11.3 Malloryfjellet, 7.1 Malmberget, 20.8b Malmgrenfjellet, 7.1 Malte Brunfjellet, 4.10, 17.7 Manbreen, 20.1 Mansfieldfjellet, 9.1 Marchaislaguna, 9.9 Marhogda, 18.7 Mariebreen, 5.3 Marietoppen, ,10.10, 16.1, 20.8b Mariekammen, 10 Markhambreen sheet C 12, 1.11 Marsfjellet, 7.1 Marstrandabreen, Marstrandodden, 4.2 Martensoya, 6 Martinfjella, 10 Marv~gen, 10.1 Mathiasbreen, 10 Mathiesenfjellet, 9.1 Mathewbreen, 4 Mathiesondalen, 5 Maudbreen, 1.7, 6.1 Mc Vitiepynten, 9 Mediumfjellet, 9.1 Mefonntoppane, 10.1, 12.1 Mendel~jevbreen, 20.8b Merakfjellet, 9.1 Meranfjellet, 10.10, 20.8b Meranpynten, 10 Methuenbreen, 4, 5 Methuenfjellet, 9.1 Meyerbukta, 4, 6 Mezenryggen, 4 Midifjellet, 10 Midre Lov6nbreane, 9 Midtbreen, 7.1 Midterhuken, 1.4 Midterhukfjellet, 1.4 Millarodden, 4 Mimerbukta, 4, 5 Mimerdalen, 8.1, 16.1

459 Minebukta, 6 Minkinbreen, 4.10 Minkinfjellet, 17.7 Mirefjellet, 20.8b Miseryfjellet, 1.4, 11.3 Mistakodden, 1.4, 18.1 Mitrahalvoya, 1.4, 8.1 Mittag-Lefflerbreen, 1.7, 4.10 Mj61nerfjellet, 5.2 Moefjellet, 9 Moffen, 1.2 Mohnbukta, 18.7 Mohnhogda, 5.6, 18.1 M611erfjorden, 8.1 Monacobreen, 1.7 Monacofjellet, 9.1 Monfjellet, 20.8b Morabreen, 9.1 Morebreen, 20.8b Morentangen, 10.1 Moskushamna, 3 Mosselbukta, 1.2, 7.1 Mosselbukta sheet C4, 1.11 Mosseldalen, 5 Mosselhalvoya, 1.4, 7.1 Motalafjella, 9.1, 14.1, 14.6 Mtihlbacherbreen, 10.1, 20.8b Mtillerneset, 9.1 M umien, 4.10 Murchisonfjorden, 1.2, 6.1 Murraybreen, 9.1 Myklegardfjellet, 4.4 Nannbreen, 10 Nansen Bank, 8.12 Nansenbreen, 1.7, 9.1 Nathorst Land, 1.3 Nathorstbreen, 1.7, 4.6, 10.1 Nathorstdalen, 4 Negerfjellet, 4.9 Negerpynten, 1.4, 18.1 Negribreen, 1.7 Negribreen sheet D8, 1.11 Neptunfjellet, 7.1 Neukpiggen, 9 Newtontoppen, 1.4 Nidedalen, 16.8 Nielsenfjellet, 1.4, 9.1 Nigerbreen, 10 Nilsenbreen, 6.1 Nissenfjella, 1.4 Njotneset, 10.1 Nord Russoya, 6 Nordaustlandet, 1.2 Nordaustpynten, 5.7 Nordbreen, 1.7, 7.1 Nordbukta, 10.1, 10.4, 12.6 Norde Franklinbreen, 6.1 Norde Rep~ya, 6.1 Nordenfjeldskebreen, 9 Nordenski61d Land, 1.3 Nordenski61dbreen, 1.7 Nordenski61dbukta, 1.2 Nordenski61dbukta sheet E2, 1.11 Nordenski61dkysten, 1.4, 10.1 Nordfjorden, 1.2 Nordflaket, 11.1 Nordhamna, 11.3 Nordlikollen, 20.8b Nordlistoppen, 20.8b Nordkapp, 1.2, 6.1 Nordkapp (Bjornoya), 11.3 Nordmannsfonna, 1.7 Nordmarka, 6.1

460 Nordneset, 5.7 Nordporten, 6.1, 7.1 Nordstebreen, 10 Nordstetinden, 10 Norgekollen, 6 Normanbreen, 6.1 Norskebanken, 1.5, 1.7, 8.12 Norskehamna, 11.3 Norstr6mfjellet, 4 Nottinghambukta, 10.1 Nova, 20.8b Nupen, 10 Ny-Alesund, 1.2, 9.1 Ny Friesland, 1.3 Nyflua, 9 Nygaardbreen, 21.6 Oberonhamaren, 7.1 Odettfjellet, 4.10 Okstindane, 1.4, 21.1 Olav V Land, 1.3 Olenellusbreen, 10 Olenidsletta, 7.1, 14.2 Olsokbreen, 1.7, 10.1 Olsokneset, 10.1 Olvastdrnet, 8 Oppdals~ta, 4.4 Ormen, 7.1 Orsabreen, 9.1 Orustdalen, 17.7, 20.8b Orustosen, 10 Orvelva, 11 Orvinelva, 4 Orvin Land, 6.1 Orvindalen, 10.4 Osbornebreen, 9.1 Oscar II Land, 1.3 Oslobreen, 1.7, 7.1, 14.2 Osodden, 10.1 Ossian Sarsfjellet, 9.1 Ostra Bramatoppen, 10 Ostre Tvillingoddane, 4.1 Ostrogradskifjella, 1.4, 10.1, 20.8b Oxfordbreen, 7.1 Oxfordhalvoya, 5.3, 6.1 Oyangen, 11.3 Oydebreen, 20.8b Oyrlandet, 1.4, 10.1 Oyrlandsleira, 4.7 Oyrlandsodden, 1.4, 10.1 Oyrnes, 9.1 Paierlbreen, 10 Palanderbreen, 5.3 Palanderbukta, 1.4, 5.3 Palasset, 4.12, 9.1, 17.7 Palatiumfjellet, 9.1 Paleontologryggen, 1.4, 20.1 Paradisbreen, 8.4 Parisbreen, 7.1 Paskefjella, 10.1, 20.8b Passet, 5.7, 18.7 Passhatten, 4.9, 18.1, 18.7, 20.8b Peachflya, 9 Peder Kokkfjellet, 10 Penckbreen, 1.7, 4.6, 10.1, 20.8b Pentavika, 6.1 Perleporten, 11.3 Perriertoppen, 1.4 Persberget, 6 Persiskammen, 9.1 Perthesoya, 5.3 Pescheloya, 5 Peterbukta, 9

PLACE NAMES Petrellskaret, 9 Petrovbreen, 7.1 Petuniabukta, 4 Philippbreen, 5 Pikebukta, 5.7 Pilsudskifjella, 20.8b Pinkie, 12.1 Pitefjellet, 20.8b Pitnerodden, 4 Planetfjella, 7.1 Planteklofta, 4 Planteryggen, 4 Platenhalvoya, 6 Plurdalen, 1.7 Polakkbreen, 10.1 Polakkfjellet, 4.6, 20.8b Polarisbreen, 7.1, 13.2 Pothem, 7.1 Polhemhogdene, 7.1 Poolepynten, 9.1 Poulabreen, 1.7 Pretender, 4.12, 9.1 Pricepynten, 9.1 Princesse Alicefjellet, 8.4 Prins Heinrichfjella, 9.1 Prins Karls Forland, 1.2, 9.1 Prins Karls Forland sheet A8, 1.11 Prins Oscars Land, 6.1 Prismefjellet, 21.1 Profilbekken, 7.1 Profilbreen, 10.1 Profilstranda, 14.2 Protektorfjellet, 9.1 Pteraspistoppen, 8.4 Puddingen, 8.4 Pukkelen, 20.8b Pulkovofjella, 10.1, 20.8b Purchasneset, 6.1 Purpurdalen, 1.7 Pyefjellet, 4.10 Pyramiden, 1.2, 4.10, 17.7 Pyttholmen, 10 Qvigstadfjellet, 20.8b Qvanstrombreen, 9.1 Rabotdalen, 8.4, 8.7 Ragnardalen, 4 Ragundafjellet, 20.8b Raksodden, l 0.1 Ramfjellet, 4.8, 9.1, 19.11 Randberget, 10.1 Rapotpasset, 8.4 Rasstupet, 10 R~ittvikfjellet, 9.1 Raudberget, 7.1 Raudfjellet, 1.4 Raudfjordbreen, 1.7, 8.4 Raudfjorden, 1.2, 8.1, 8.7 Raudryggen, 5.2 Recherchebreen, 1.7, 4.6 Recherchefjorden, 1.2, 10.1 Reinbokkdalen, 7.1 Reindalen, 1.7, 4.4 Reinodden, 4.6, 20.8b Reinsdyrflya, 1.4, 8.1, 16.1 Reinsdyrflya sheet B4, 1.11 Reischachtoppen, 10.10 Renardbreen, 10.1 Renardodden, 10.1 Repoyane, 6.1 Repoyane sheet F2, 1.11 Retziusfjellet, 1.4, 5.7 Revdalen, 10.1, 10.10

Revnosa, 18.7 Revtanna, 20.8b Richarddalen, 8.7 Richardlaguna, 9.1 Richardvatnet, 8.4 Richthofenberget, 20.8b Rifleodden, 11.3 Rijpbreen, 6.1 Rijpdalen, 1.7 Rijpfjorden, 1.2 Rijpfjorden sheet E3, 1.11 Ringertzoya, 6.1 Risefjella, 1.4, 21.1 Rittervatnet, 7.1 Rivieratoppen, 8.4 Raoldtoppen, 6.3 Robertsonfjellet, 20.8b Rochesterpynten, 10.1 Rodahlfjellet, 7.1 Roedvika, 11.3, 16.1 Rokensglta, 10 Rordenryggen, 7.1 Ros6nfjella, 7.1 Rosenthalbreen, 5.3 Rossbukta, 9 Rotundafjellet, 4.9, 18.1 Roulletega, 19.14 Royal Societybreen, 7.1 Royevatnet, 11.3 Roysbreen, 20.8b Roysfjellet, 20.8b Roysneset, 10.1 Rozyckibreen, 20.8b Rundisen, 5.7 Rungnekampen, 7.1 Rurikfjellet, 1.4, 19.14, 20.8b Russelva, 11 Russehamna, 11.3 Ryss6, 6 Sabine Land, 1.3 Sabinebukta, 6.1 Salfjellet, 9.1 Salpynten, 9.1 Samarinbreen, 10.1 Samarinvgtgen, 10.10, 20.8b Sandbukta, 9.1 Sanderbreen, 7.1 S~irnafjellet, 9.1 Sarsbukta, 9 Sarsoyra, 9.1 Sarstangen, 1.4, 9.1 Sassendalen, 1.7, 4.4 Sassenfjorden, 1.2 Saurieberget, 18.1 Saussureberget, 20.8b Savitsjtoppen, 10 Scaniahalvoya, 5.3 Scheteligfjellet, 1.4, 9.1, 20.8b Schjelderupbreen, 21.6 Sch6nrockfjellet, 1.4, 4.5, 19.11 Schweigaardbreen, 6.1 Scoresbyoya, 6.1 Scotiadalen, 9.1 Scotiafjellet, 9.1 Scott-Ruudfjellet, 20.8b Sederholmfjellet, 7.1 Sedwickjokelen, 7.1 Sefstr6mbreen, 9.1 Seipfjellet, 4 Selanderneset, 6.1 Seligerbreen, 8 Seljehaugfjellet, 4 Selmaneset, 9.1, 18.1

PLACE NAMES Selv~gen, 9.1 Semmeldalen, 1.7 Sentinelfjellet, 5 Sentralisen, 7.1 Sergeijevfjellet, 10 Serlabreen, 8.4 Sesshogda, 9 Signehamna, 4 Signyfjellet, 7.1 Sigfredbogen, 12.1 Sigurdfjellet, 1.4, 8.1 Siksaken, 18.1, 20.8b Siktefjellet, 8.4, 16.1 Siljanfjellet, 9.1 Siljestr6mkammen, 20.8b Singerfjella, 4.5 Sinkholmen, 10 Sjdanovfjellet, 10 Sjettebreen, 8.1 Sj6grenfjellet, 5.7, 18.1 Sjubrebanken, 8.12 Sjuoyane, 1.2, 6.1 Sjuoyane sheet El, 1.11 Sjuoyflaket, (submarine bank of Sjuoyane), 6 Skakken, 20.8b Skdlfjellet, 10 Skansbukta, 4, 7 Skardkampen, 10 Skarsbukta, 3 Skiferkammen, 4 Skinfaksebreen, 7.1 Skipperbreen, 14.6 Skjoldkollen, 8 Skoddebukta, 10.1 Skoddefjellet, 10.10 Skotteknausen, 7.1 Skuggefjellet, 16.8 Skuld, 11.3, 18.1 Slaadbukta, 8.1 Slaklidalen, 10 Slangen, 7.1 Slettneset, 10 Slettfjelldalen, 10 Slettnesbukta, 10 Slottsmoya, 4.4 Slyngfjellet, 10.1 Smfihumpen, 5.17 Smalegga, 4.7, 18.7 Smalfjorend, 6 Smeerenburgbreen, 1.7 Smeerenburgfjorden, 1.2 Smerudknausen, 10 Smutsbreen, 7.1 Snelvatnet, 11.3 Snippen, 9 Snofjella, 8 Snokrossen, 10 Snovola, 19.11 Sofiebogen, 10.1 Sofiekammen, 10.1, 14.2 Solfjellet, 7.1 Solhogda, 10 Sommerfeldtbukta, 10.1 Somovaksla, 4.6, 20.8b Somovbreen, 18.1 Somovfjella, 4.6, 18.7 Sophie Canyon, 8.12 Sore Nathorstmorena, 20.8b Sorbreen, 1.7, 7.1 Sore Franklinbreen, 6.1 Sore Rep~ya, 6.1 S~rfjellet, 7.1 Sorgfjorden, 1.2, 7.1 Sorhamna, 11.3

Sorkapp, 10.1 Sorkapp sheet C 13, I. 11 Sorkappbanken, I 1.1 Sorkapp Land, 1.3 Sorkappfonna, 1.7, 4.7, 10.1 Sorkapp~ya, 1.2, 10.1 Sorlifjellet, 20.1 Sormarka, 6.1 Sorvestnaget, 11.1 Sparrefjellet, 9.1 Sparreneset, 6.1, 14.2 Spitsbergen, 1.2 Spitsbergenbanken, 11.1 Sporehogda, 4.10 St. Jonsfjorden, 1.2, 9.1, 17.7 St. Jonsfjorden sheet B8, 1.11 Stairhogdene, 9.1 Stanislavskikammen, 20.8b Stappen, 11.3 Starostinfjellet, 10.10, 20.8b Stavkjerka, 9.1 Steenfjellet, 20.8b Steinflya, 11.3 Steinpynten, 9.1 Steinvikskardet, 10 Stemmeknausane, 9.1 Sten De Geerfjellet, 20.8b Stensi6fjellet, 18.1 Stertane, 9.1 Stertbreen, 9.1 Stevatnet, 11.3 Sticky Keep, 1.4 Stjordalen, 8 Stollintinden, 20.8b Stolovajafjellet, 20.8b Stonebreen sheet FI0, 1.11 Storbanken, 1.5 Storbreen, 1.7, 4.5, 10.1, 18.1, 20.8b Storfjordbanken, 1.5 Storfjorden, 1.2, 20.8b Storfjordrenna, 1.5, 11.1 Stormbukta, 4.7, 10.1 Stormerfjellet, 7.1 Storoya, 1.2 Stor~ya sheet H3, 1.11 Storskavlen, 5 Storsteinhalvoya, 1.4, 6.1 Storsteinhalvoya sheet D3, 1.11 Stortrollet, 9.1 Storvika, 10.1 Strandlinuten, 20.8b Straumtangen, 8 Strongbreen, 1.7 Strykjernet, 20.8b Stubendorffbreen, 1.7, 7.1 Stupinden, 20.8b Subbhogda, 20.8b Sukkertoppen, 10 Sundhogda, 4 Supanberget, 10 Sutorfjella, 9.9 Svalbard, 1.1 Svalisbreen, 20.8b Svanbergfjellet, 1.4, 7.1 Svartberget, 5.3 Svarteltet, 20.8b Svartfjella, 9.1 Svartfjellstranda, 9.1 Svartknausane, 6 Svartknausflya, 6 Svartneset, 6.1 Svartperla, 20.8b Svartpiggen, 1.4, 21.1 Sveabreen, 1.7, 9.1, 9.6, 20.8b

461 Sveagruva, 1.2 Sveaneset, 4.9, 9.1, 18.1 Sveanor, 13.2 Svedenborgstupet, 19.11 Sveisarfonna, 10 Svenbreen, 4.10 Svenfjellet, 8.1 Svenskeega, 9 Svenskehuset, 3 Svenskoya, 1.2 Svenskoya sheet G7, 1.11 Sverrefjellet, 1.4, 21.6 Svingfjellet, 7.1 Sykorabreen, 20.8b Sylodden, 4.8 Syltoppen, 9.1, 18.7 Systemafjellet, 4 T~breen, 7.1 Talavera, 5 Tangvika, 9.1 Tappen, 7.1 Tdrnkanten, 9 Tavlefjellet, 1.4, 21.1 Teistberget, 18.7 Tempelfjorden, 1.2, 4.10 Templet, 1.4, 4.10 Terre Glac6e Russe, 1.7 Terrierfjellet, 4.10, 7.1 Thiisfjellet, 9 Thomsonfjella, 9.1 Tilasberget, 4.6, 18.7, 20.8b Tirolarpasset, 4.6 Tjuvfjorden, 18.1 Todalen, 4.2 Tokammane, 7.1, 14.2 Tokross~ya, 10.1 T~mmerneset, 5.7 Tomptegubben, 9.1, 20.8b Tonedalen, 10 Tonefjellet, 1.4 Topiggane, 7.1 Torafjellet, 9.1 Tordenryggen, 7 Tordenskjoldberget, 5.7 Tordenskjoldbukta, 9.1 Torell Land, 1.3 Torellbreen, 10.1 Torellbreen sheet B 12, 1.11 Torellneset, 1.4, 5.3 Torellnesfjellet, 5.3, 18.1 Tornefjellet, 9.1 Tovikbukta, 5.17 Transparentbreen, 7 Traunkammen, 10.10, 20.8b Tre Kroner, 1.4, 9.1 Tre Kroner sheet B7, 1.11 Trekloverbreen, 20.8b Treskelen, 10.1, 18.7 Treskelodden, 4.9, 18.1 Treskeloppen, 20.8b Triasnuten, 10 Trikolorfjellet, 4.10 Trillingane, 20.8b Trinutane, I0 Trollfuglfjella, 4.12, 17.7 Trollheimen, 9.1 Trollslotten, 9 Trollstedet, 19.11 Tromsobreen, 4.7, 20.8b Tromsoflaket, 21 Trondheimfjella, 9.1 Tronfjellet, 4 Triungen, 4.10

462 Trygghamna, 9. l, 18.1 Tryggvebreen, 7.1 Tschermakfjellet, 4.9, 18.1 Tsjebysjovfjellet, 10.1, 10.10 Tsjernajafjellet, 10 Tumlingodden, 18.1, 18.7 Tunabreen, 1.7, 7.1 Tunheim, 1.2, 11.3 Tunsfjodalen, 10 Tusenoyane, 1.2 Tusenayane sheet El2, 1.11 Tverraksla, 20.8b Tverrsjoen, 11.3 Tvillingoddanen, 18.1 Tviroysegga, 20.8b Tvitoppen, 18.7, 20.8b Tyrrellfjellet, 4.10

Ullaberget, 4 Ulveberget, 6 Ulvebukta, 5.3 Umefjellet, 20.8b Uranusfjellet, 7.1 Urd, 11.3, 18.1 Urmstonfjellet, 1.4 Urnetoppen, 10 Ursafonna, 1.7 Uversbreen, 1.7, 9.1 Vaigattbogen, 1.2, 7.1 Vaigattfjorden sheet D6, 1.11 Vaktaren, 1.4, 21.1 Valen, 7.1 Valhallfonna, 1.7, 14.2 Vallotfjellet, 9.1 Van Keulenfjorden, 1.2, 4.9, 10.1 Van Keulenfjorden sheet Bll, 1.11 Van Mijenfjorden, 1.2 Van Mijenfjorden sheet B10, 1.11 Van Muydenbukta, 10.1 Vardeborg, 4 Vardebreen, 4 Vardebukta, 18.1 Varderpiggen, 10 V~trsolbukta, 20.8b Vasahalvoya, 1.4 Vasahalvoya sheet A4, 1.11 Vassdalen, 4.8

PLACE NAMES Vasilievbreen, 1.7, 10.1, 20.8b Vassfaret, 7.1 Vatnelieoyra, 21.6 Vegafonna, 1.7, 5.3 Vegardbreen, 9 Vegardfjella, 9.1 Velkomstpynten, 1.4 Venernbreen, 1.7, 9.1 Vengeberget, 10 Venusfjellet, 7.1 Verdalen, 8 Verdande, 11.3, 18.1 Verlegenhuken, 1.4, 7.1 Vermlandryggen, 20.8b Vesalstranda, 11.3 Vestervhgen, 10.4 Vestbanken, 11.1 Vestfjorddalen, 1.7 Vestfjorden, 1.2 Vestflya, 9.1 Vestfonna, 1.7 Vestg6tabreen, 9.1, 14.2, 14.6 Vestnesa, 8.12 Vestre Centerfjellet, 20.8b Vestre Torellbreen, 1.7 Vestre Tvillingoddane, 4.1 Veteranen, 1.7 Veteranfjella, 7.1 Vetternbreen, 1.7, 9.1 Vibebukta, 5.3 Vibebukta sheet F5, 1.11 Vibehogdene, 5.3 Vikinghogda, 4.9, 18.1 Vildadalen, 7.1 Vimsodden, 10.1, 13.2 Vindbukta, 6.1 Vindodden, 18.1 Vomma, 11.3 Von Postbreen, 1.7 Vonbreen, 1.7, 8.1 Voringen, 20.8b Vortefjellet, 9.1 Vrangpeisbreen, 10.1 Wahlbergoya, 1.2 Wahlenbergbreen, 1.7, 9.1, 20.8b Wahlenberget, 5 Wahlenbergfjellet, 10.1 Wahlenbergfjorden, 1.2

Wahlenbergfjorden sheet E4, 1. l 1 Wallenbergfjellet, 18.1 Wallisberget, 20.8b Wedel Jarlsberg Land, 1.3 Weenfjellet, 4 Werenskioldbreen, 1.7, 10.1 Werenskioldfjellet, 5.17 Westbyfjellet, 7.1 Westmanbukta, 6 Wibebreen, 10 Wichebukta, 4.4, 18.1 Wiederfjellet, 10 Wijdefjorden, 1.2, 6.1 Wilhelmberget, 5.2 Wilhelmoya, 4.9 Wilhelm~ya sheet E6, 1.11 Willybreen, 5 Wilsonbreen, 7.1 Wilsonlaguna, 9.1 WimanJjellet, 4 Winsnesbreen, 5.3, 6.1 Winsnesfjellet, 1.4 Wittenburgfjella, 9.1, 20.8b Woodfjorddalen, 1.7 Woodfjorden, 1.2, 16.1 Woodfjorden sheet B5, 1.11 Wordiekammen, 1.4, 4.10, 17.7 Worsleybreen, 6.1 Wrightfjellet, 20.8b Wulffberget, 8.4 Wurmbrandegga, 10.10 Ydalkampen, 7.1 Yermak Plateau, 1.5, 8.12 Ymerbukta, 4.8, 9.1 Ymerdalen, 11.3, 14.2 Yoldiabukta, 9.1 Ytterdalssdta, 10 Zawadskibreen, 10.1 Zeipeldalen, 7.1 Zeipelfjella, 6 Zeipelodden, 5.3, 6.1 Zeppelinhamna, 10 Zeppelinfjellet, 20.8b Zillerberget, 4.6, 19. l 1 Zittelberget, 20.8b Zornfjellet, 9.l

Glossary of stratigraphic names

This index attempts to list in alphabetical order all proper stratigraphic names from Svalbard literature. It cannot be complete, although most names encountered during work on this book have an entry. Each entry begins with the name and its stratigraphic rank abbreviated. The name occurs and may be defined in the translation of the Russian Publication of Gramberg et al. (1990, Dallmann & Mork 1991 (eds)). This is a valuable source of further information which supplements this work. Gramberg et al. is indeed especially valuable because the Russian entries are interpreted by the authors' colleagues. However, the presently recommended equivalents of many named units are different from that work. * Names have been recommended for use by the Stratigrafisk Komite for Svalbard (SKS) of Norsk Stratigrafisk Komite (NSK). At the time of collation of this book the SKS had provisionally agreed only on post-Devonian stratigraphic nomenclature, hence there are no names as yet recommended by the SKS for preCarboniferous stratigraphy. Tertiary names were approved by NSK in December 1995, Carboniferous and Permian names by SKS in April 1996. They have been cited as Dallmann et al. (1995/96). $ The Mesozoic names, in draft yet to be recommended by the Mesozoic Subcommittee and SKS were available in July 1997 only after this text was finalized (Mork et al. in 1997 SKS). All names printed in bold type are favoured in this work. Italic type denotes those names that are not favoured for current use. However they are included in the list so as to relate to other literature. Their equivalent preferred unit is indicated by the symbol ~meaning that the relationship may be approximate only. The reason for preference or not is not explained in the glossary, but it may found in the text of the chapters noted at the end of each entry. Names in plain roman type are awaiting consideration. The upper or lower case initial of the rank term indicates formal or informal status. The second part of each entry is the reference to the early use of the name. No further reference is given where a name changes rank or status because it is the rock units which retain their name in successive schemes. However, where some significant change of meaning has been recommended, e.g. by SKS, the reference added. The reference is followed by the unit of next higher rank (if any) then by the units of next lower rank in it (if any). The penultimate entry is a rough indication only of age. Some are in two parts; a period or era symbol, followed by the three letter stage code. These conventions generally follow Harland et al. (1990) and are listed and modified in Chapter 3. This list should not be used as a source for the ages of the units. It is intended to be a helpful clue. In attempting to avoid multiple entries for the same unit separated only by alphabetical sorting many original foreign terms are put in an English language form. Such terms as French Niveau etc., German Schiehten, Kalk etc; Russian Svita; Pashka etc. may be translated so as to be listed with related unit names. For the same reason to streamline the list the proper name is listed only once with its current rank (e.g. formation) regardless of changes in rank (member, group etc.) or earlier terms such as series. Thus later authors introducing a new classification may not be cited if the same package of rock is still identified by the original name. SKS is pressing for all names to be spelled as in current official maps. This recommendation is followed here for all relatively new names established when the then current official maps were readily available. In this work older names, long in use in the literature, according to the priority principle are not changed whatever their grammatical form. It is preferred here only to change a name from its first published use when a significant investigation has shown a new scheme to be necessary. The practice of changing a name with no more than linguistic justification, and claiming authorship for it, is deprecated. Nevertheless in some cases the current place name is

completed here in square brackets where it differs. Constituent units are listed generally from the top down. As explained in Sections 18.3 and 19.3.2 correlated units in the Hammerfest Basin have been included. Aavatsmarkbreen Fm (Harland et al. 1993) Comfortlessbreen

Gp; V2, Edi; 9 13. * Aberdeenflya Fm (SKS 1996, after Rye Larsen ) McVitiepynten Sbgp; Pg; 9 20. *t Adriabukta Fro. (Birkenmajer & Turnau 1962) Billefjorden Gp; Meranfjellet, Julhogda, Haitanna mbrs; Cl,Tou-Vis; 10, 17. :~t Adventdalen Gp (Parker 1967) Janusfjellet Subgp; Carolinefjellet, Helvetiafjellet, Rurikfjellet, Agardhfjellet, Kong Karls Land, Kongsoya fms; J2-K~; 4 5, 19; it has been suggested to include Kolmule, Kolje, Knurr, Hekkingen and Fuglen fms of Hammerfest Basin. t Adventfjorden Schichten (Vonderbank 1970)~Firkanten Fm; Pg, Pal; 4 20. Advocat Seam (Orvin 1934) Kongsfjorden Fm, Kolhaugen Mbr; Pg, Pal; 9 20. Agnes-Otelie seam (Orvin 1934)= Otelie Seam. t Agardhfjellet Fm (Parker 1967) Janusfjellet Subgp; Slottsmanoya, Oppdals~ta, Lardyfjellet, Oppdalen mbrs; J2-3, Bth-Tth; 4, 19. t Akademikerbreen Gp (Harland & Wilson 1956; Harland et al. 1966) Lomfjorden Spgp; Backlundtoppen, Draken, Svanbergfjellet + Grusdievbreen fms; Neptz; 7 12. Akkar Mbr (Mork et al. SKS) Fruholmen Fm in Hammerfest Basin; Tr3, Nor. $ Alge Mbr (Mork et al. SKS) Fuglen Fm in Hammerfest Basin; J3, CIv. t Alasdairhornet Fm (Harland et al. 1979) Peachflya Gp; V ?Var; 9, 13. t Albertbreen Fm (Friend et al. 1997) Siktefjellet Gp; D1, Lok; 8,16. Albreen Mbr (Wallis 1969) Vildadalen Fm; Neoptz; 7 12. Alfred Larson-toppen unit? t Alfredfjellet Fm (Krasil'shchikov & Livshits 1974)~Hambergfjellet Fm; P1, Art; 11, 17. t Alkhorn Fm (Holtedahl 1913; Harland et al. 1979) St Jonsfjorden Gp; six divisions not formalized (Harland et al. 1993) V1, Varl; 9, 13. [Alkhornet]. Alkhornkalk (Holtedahl 1913)=Alkhorn Fm; V1, Vara; 9, 13. t .&lryggen Mbr (Wallis 1969) Vildadalen Fm; Neoptz; 7, 12. Ambigua limestone (Andersson 1990)~Kapp Kgtre Fm; C2, Bsh-Mos; 11, 17. Anasibirites horizon (Buchan et al. 1965) ,.o part of Iskletten Mbr. t Andr~e Land Gp (Harland et al. 1974); Liefde Bay Spgp; Mimer Valley, Wood Bay, Grey Hoek, Wood Bay Fms; D1-D3; Pra-Frs; 8 10, 16. Andr~ebreen Fm (Friend 1961) Red Bay Gp; Buchananhalvoya Mbr; DI: Lok, 8 16. t Andvika Mbr (?Birkenmajer 1972) H6ferpynten Fm; Neoptz; 10, 12. t Angellfjellet Mbr (Birkenmajer & Narebski 1960; Birkenmajer 1992) Skgtlfjellet Fro; Ptz; 10, 12. t Anhydrite member (Bates & Schwarzacher 1958)~part of Gipshuken Fm; P1, Sak-Art; 4, 17. t Annabreen Fm (Wilson in Harland 1960; Harland et al. 1979) Comfortlessbreen Gp; V2, ?Edi; 9, 13. t Anservika beds, mbr (Cutbill & Challinor 1965)~Terrierfjellet Mbr; C2, Mos; 4, 17. Asbestodden unit (?) Chamberlindalen Fm. Antaretiefjellet Fm (Armstrong & Smith in press) Ymerdalen Gp; (= Tetradium Limestone of Holtedahl 1920); 03; 11, 14.

464 t

STRATIGRAPHIC GLOSSARY

Arctoceras horizon (Frebold 1930) ~ upper Fish Niveau ~ Sticky

Keep Fm. t t

t

Arctoeeras layers (Stolley 1911) ~ lower Sticky Keep Fm. Argillite unit (Klubov 1965)N lower Edgeeya Fm. Ariekammen Fm (Birkenmajer 1958, 1992) Isbjernhamna Gp;

Ptz; 10, 12. t Arkfjellet Fm (Major & Winsnes 1955) Sofiekammen Gp; O; 10, 14. t Arnesodden Bed (Smith et al. 1976) Wilhelmeya Fm in Svenskoya; Tr3-J1; 5, 18, 19. Askeladden Seam (Major & Nagy 1972), Firkanten Fm in E Nordenski61d Land; Pg, Pal. ?CH. *t Aspelintoppen Fm (Major & Nagy 1972) Van Mijenfjorden Gp; Pg; 4, 20. Astarte horizon (Feyling-Hanssen 1955); Holocene raised beach deposits in Billefjorden; 21. t Atomfjella Complex (Krasil'shchikov 1970) Stubendorffbreen Spgp; Harkerbreen + Finnlandveggen gps. Paleoptz; 7, 12. t Aucella Shale (Hagerman 1925)~ Janusfjellet Subgp; JK; 4, 19. t Austfjorden gneisses (Harland & Wilson 1956),-~Eskolabreen Fm; Palptz; 7, 12. Austfjorden Mbr (Vogt 1929) Wood Bay Fm, D1, Pra-Ems; 8, 16. t Austfjorden series (Harland & Wilson 1956)~ coastal completof Harkerbreen § Finnlandveggen gps; Palptz; 7, 12. t Ausffonna Fm (Flood et al. 1969) in E Brennevinsfjorden Gp; revised (Gee & Teben'kov 1996) in middle Nordaustlandet, ?equiv. Lower Franklinsundet Gp. in W; Neoptz; 6, 12. t Austjokelen Fm (Merk et al. 1982) Kapp Toscana Gp in S. Spits. ~Tschermakfjellet Fm; Tr2_3, Lad-Crn; 4-18. (Merk et al. SKS prefer Tschermakfjellet Fm) Austre Torellbreen Gp (this work) to combine the younger (?Vendian) parts of the Werenski61d(breen) Group, i.e. Slyngfjellet, Deilegga, Jens Erikfjellet and Elveflya fms ~ Konglomeratfjellet Gp to N; Ptz, V; 10, 13. Backaberget Fm (Krasil'shchikov 1967) Gotia Gp; comprises the 5 lower divisions of Kulling's Sveanor Fm; ?V; 6, 13. t Backlundtoppen Fm (Harland & Wilson 1956; Harland et al. 1966) Akademikerbreen Gp; 6mbrs: U. Dst; Shale; M. Dst, Stromatolitic Dst; L. Lst; Oolitic Lst.; Neoptz; 7, 12. t Backlundtoppen oolites (Harland & Wilson 1956)~L. Backlundtoppen Fm. t Baklia fm (Harland et al. 1979) Scotia Gp; V ?Edi; 9, 13. * Balanuspynten fm (SKS 1996) Buchananisen Gp; Sarstangen, Sarsbukta mbrs; Pg; 9, 20. t Bangenhuk Fm (Harland et al. 1966) Bleikfjellet Subgp; Femmilsjeen + Flateyrdalen mbrs (= Camryggen Gneiss in S) Paleoptz; 7, 12. Bangenhuken Cpx (Helman et al. 1979)=Bangenhuk+ Vassfaret fms. Harkerbreen Gp (in Atomfjella Cpx, in Stubendorffbreen Supergroup), Ptz; 7. Bangenhuken Cpx (Hellman et al. 1997)= Bangenhuk + Vassafaret fms. Harkerbreen Gp (in Atomfjella Cpx, in Stubendorffbreen Spgp), Ptz; 7. ~f Barents[fjellet] Fm (Atkinson 1960; Harland et al. 1979) Grampian Gp; ?O-S; 9, 14. t Barents Group (Atkinson 1956)~ Barents Fm Barentsburg Fm (Livshits 1967)~ Firkanten Fm; Pg; 4, 20. t Barentsoya Fm (Lock et al. 1978; Merk et al. 1982) Sassendalen Gp in Barentseya & Edgeeya; Trl 2; 5, 18. (Merk et al. SKS. recommend replace by Botneheia and Vikinghegda fms). Barentsfjellet Fm. t Basal mbr (Worsley 1973) Wilhelmeya Fm; ?Rht; 5, 18. t Basal quartzite fro (Ohta 1982) ? 40-110m. *t Basilika Fm (Major & Nagy 1964) Van Mijenfjorden Gp; Pg, Pal; 4, 20. t Basissletta Mbr (Fortey & Bruton 1973) Kirtonryggen Fm; Ol, Can2; 7, 14. *t Battfjellet Fm (Major & Nagy 1972) Van Mijenfjorden Gp; Pg; 4, 20. Bautaen cgl mbr, Treskelodden Fm in Hornsund.

* Bayelva Mbr (SKS 1995) Breggerbreen Fm; Pg, Pal; 9, 20. t Bellsund beds (Smevskiy 1967)~Pleistocene strata at Calypsobyen, Kapp Lyell. Bellsund dolomite (Hjelle 1962) = Lower member of LAgnesrabbane Fro; Va ?Var; 10, 13. t Bellsund Group (Krasil'shchikov & Kovoleva 1976)~all Vendian tilloids in W Spits., includes Early and Late Varanger. t Bellsund-Dunderdalen tillite (Hjelle 1969) ~ all Vendian tilloids N and S of Bellsund, mostly Early Varanger but not distinguished. t Ben Nevis Fm (Kiaer 1916) Red Bay Gp; D1, Lok; 8, 16. t Bergnova Fm (Birkenmajer 1975) M. Deilegga Gp; V; 10, 13. t Bergskardet Fm (Birkenmajer 1975) U. Deilegga Gp; V; 10, 13. t Bertel(toppen) Member (Barbaroux 1966)~ lower part Nielsenfjellet Fm. t Billejyorden beds (Semevskiy 1967)~ Quaternary, older than his Bellsund beds. Billefjorden Stage (Boulton et al. 1982) Quaternary equivalent to Semevskiy's (1967) Bellsund Beds. *t Billefjorden Gp (Cutbill & Challinor 1965) Btinsow Land Spgp; Mumien, Herbyebreen, Vegardfjella, Orustdalen, Sergeijevfjellet, Hornsundneset, Adriabukta, Nordkapp, Reedvika fms; D3-C1; Fam-Tou-Vis; 4, 17. * Birger Johnsonfjellet Mbr (SKS 1996) Mumien Fro; C1, Vis; 4, 17. Biskayerfonna Subgp (Friend et al. 1997) Krossfjorden Gp; Biskayerhuken + Montblane fms; Ptz; 8, 12. t Biskayerhuken Fm (Harland et al. 1966; Hjelle & Lauritzen 1982 after Gee) Biskayerfonna Subgp; Ptz; 8, 12. Bjornbogen Fm (Pchelina 1980, 1983) Kapp Toscana Gp = Norian age deposits in E Sval. t Bjornbogen horizon (Pchelina 1980)~her Bjernbogen, Tvillingodden, Keilhaufjellet, Flatsalen, Koberg mbrs ~ Rhaetian age deposits. Bjornbogen Mbr (Worsley 1973) Wilhelmoya Fm; Tr3-J1, Rht?Het; 5, 18. Bjornaya Gp (Harland et al. 1993); Sorhamna, Russehamna fins; V; 11, 13. * Bjornsonfjellet Mbr (?SKS 1996) Frysjaodden Fm; Pg; 4, 20. t Bjorvigfjellet Fm (Challinor 1967) ? = Trondheimfjella Fm; preVend; 9, 13. t Black Carbonate Pelite (Knoll & Ohta 1988)~ Roysha Fm. * Black Crag Beds (Cutbill & Challinor 1965) at base of Wordiekammen Fm; C2, Kas; 4, 17. t Black shale f m (Hjelle et al. 1979),-~Black Carbonate Pelite (BCP) of Knoll & Ohta (1988), within Scotia Group of Prins Karls Forland ~ Roysha Fm. t Black shales and yellow flags (Gregory 1921)~part of Sticky Keep Fm. * Biadegga Mbr (Gjelberg 1984) Hyrnefjellet Fm; C2, Mos; 4, 17. :~t Blanknuten Beds (Mork et al. 1982) Botneheia Fm (in E); Tr2; 4, 18; ~ Oil Shales of Falcon (1928). (Mork et al. SKS raise rank to mbr of upper Botneheia Fro). t Bl~nuten Beds (Harland et al. 1966) Cavendishryggen Mbr; Neoptz; 7, 12. Bl~revbreen Mbr (Swett 1981) Tokammane Fm; El; 7, 14. t Bl~stertoppen Fm (Birkenmajer 1959) Sofiekammen Gp; Russepasset, Flakfjellet, Ggtsbreen mbrs; 10, 14. t Bleikfjellet Subgp (Harland & Wilson 1956; Harland et al. 1992) Harkerbreen Gp; Vassfaret, Bangenhuk, Rittervatnet, Polhem, Flaten, Instrumentberget, Paleoptz; 7, 12. t Blomstrandhalvoya Fm (Harland et al. 1966) ~ Generalfjella Fm. Blue & Purple Shales (Falcon 1928),-~Tschermakfjellet Fm in Edgeeya; Tr2 3; 4, 18. t Bockfjorden gneisses (Harland 1960)~ Lower part of Krossfjorden Group; Neoptz; 9, 13. t BogeggFm (Orvin 1934; Major et al. 1956) Kongsvegen Gp; preVend; 9, 13. [Bogegga] t Bogen Mbr (Harland et al. 1966) Kingbreen Fm; six div; Neoptz; 7, 12. Bogen Mbr (Larssen et al. 1995)= belemnite bed in Kongseya Fro; Jl-2, Toa-Aal.

STRATIGRAPHIC GLOSSARY J; Bogen Bed (Mork et al. SKS) name preoccupied. *t Bogevika Mbr (Worsley & Edwards 1976) Kapp K~re Fm; C2, Bsh-Mos; 4, 17. t Bogstranda unit (Harland 1978) = Lower part of G~tshamna fm N of Hornsund; V; 10, 13. t Bohryggen Mbr (Harland et al. 1966) Smutsbreen Fm; Paleoptz; 7, 12. t Bolster Beds (Wilson 1961)~lower 1st mbr of Svanbergfjellet Fm; Neoptz; 7, 12. t Botnedalen Fm (Bjornerud 1990) Nordbukta Gp; Ptz; pre-V; 10, 12. ~t Botneheia Fm (Buchan et al. 1965) Sassendalen Gp, Somovbreen, Passhatten, Blanknuten and Karentoppen mbrs; Ans-Lad; Tr2; 4, t8. t Botneheia horizon (Pchelina 1983)~all Svalbard strata of Botneheia Fm age. t Botniahalvoya Spgp (Flood et al. 1969) Laponiahalvoya, Kapp Hansteen, Brennevinsfjorden gps; Ptz; 6, 12. Bottfjellet Band (Harland et al. 1966) above Camryggen gneiss (Femmilsjoen Mbr); Paleoptz; 7, 12. Bottom shale (Orvin 1934)~ Vardebukta Fm; Trl; 9, 18. Brachiopod cherts (Gee et al. 1952)~ Kapp Starostin Fm; P1 2: Art; 4, 17. t Brachiopod Fm (Nordenski61d 1863)~ Kapp Starostin Fm; Pl-2, Art; 4, 17. * Brattberget Mbr (Dallmann et al. 1993) Hyrnefjellet Fm; C2, Mos; 4, 17. t Brattegga Mbr (Birkenmajer & Narebski 1960; Birkenmajer 1992) Sk~dfjellet Fm; Ptz; 10, 12. Bratteggdalen Fm (Czerny et al. 1993) Eimfjellet Gp; Ptz; 10, 12. ~t Bravaisberget Fm (Mork et al. 1982)= sandy facies (mbr) of Botneheia Fm in W. Spits; Tr2; 4, 18. ~' Bredsdorffberget Mbr (SKS) Gipshuken Fro; P1, Sak-Art; 4, 17. t Brennevinsfjorden Gp (Flood et al. 1969) in W: U. sst sh, M. qi sh, L. sh.sst units., Ptz; 6, 12. Brennevinsfjorden granite (Flood et al. 1969)~ Laponiahalvoya Gp; Ptz; 6, 12. $~ Brentskardhaugen Bed (Parker 1967) Oppdalen Mbr; J2, Bth; 4, 19. ~t Brevassfjellet Bed (Worsley & Mork 1978) Kistefjellet Fm (in S)=basal part of fm; Trl; 4, 18. t Brevassfjellet Myalina beds (Birkenmajer 1977) 'upper part of Urnetoppen Mbr of Vardebukta Fm'. * Broggerbreen Fm (SKS 1996) Ny-Alesund Sbgp; Bayelva, Leirhaugen mbrs; Pg, Pal; 9, 20. *t Broggertinden Fm (Cutbill & Challinor 1965) Charlesbreen Sbgp; C2, Bsh-Mos; 4, 17. *t Brueebyen Beds (Cutbill & Challinor 1965) Tyrrellfjellet Mbr; C2,Gze; 4, 17. Buchananhalvoya Mbr (Friend et al. 1997) Andr6ebreen Fm; D1, Lok; 8, 16. * Buchananisen Gp (SKS 1995) Balanuspynten fm, McVitiepynten sbgp, Selvftgen Fm; Pg; 9, 20. t Bullbreen Gp (Harland et al. 1979) Holmesletfjella, Bulltinden, Motalafjella fms); O-S; 9, 14. t Bulltinden Fm (Horsfield 1972; Hjelle et al. 1979; Kanat & Morris 1986) Bullbreen Gp;=BH3 of Kanat & Morris; ?S; 9, 14. Biinsow Land Spgp (this work) Tempelfjorden, Gipsdalen, Billefjorden gps; D3-P2: Fam-Gua; 4, 17. Bfinsowbukta Mbr (Mork et al. SKS from unpublished work on Kong Karls Land, possibly already named by Smith et al. 1976) *t Cadellfjellet Mbr (Cutbill & Challinor 1965) Wordiekammen Fm; Matthewbreen, Gerritbreen, Black Crag Beds; C2, KasGze; 4, 17. -~ Calc-argillo-volcanic f m (Hjelle et al. 1979)~fms of St Jonsfjorden Gp; Vend.; 9, 13. t Calypsobyen beds (Semevskiy 1967)~ Quaternary unit above Billefjorden and below Bellsund beds. * Calypsostranda Gp (SKS 1995) Renardodden, Skilvika, Rochesterpynten fms; Pg; 10, 20.

465

Cambridgebreen gneisses (Harland & Wilson 1956)~ SW development of Bleikfjellet Subgp, Femmilsjoen Mbr ~ Harkerbreen Gp S.W. of Austfjorden; Paleoptz; 7, 12. *t Campbellryggen Sbgp (Gee et al. 1952) Gipsdalen Gp; Minkinfjt., Ebbadalen, Hultberget Fm; C1-C2, Spk-Bsh; 4, 17. t Camryggen gneiss (Harland & Wilson 1956) -,~S development of Bangenhuk Fm in Bleikfjellet Subgp; Paleoptz; 7, 12. Cancrinella limestone (Birkenmajer & Logan 1969) local variant of Gipshuken Fm; P1, Sak-Art; 4, 17. t Cape Sparre Fm (Kulling 1934); Gotia Group;~Sparreneset + Klackbergbukta fms; V-E-O; 6, 13. ~t Carolinefjellet Fm (Parker 1967) Adventdalen Gp; Sch6nrockfjellet, Zillerberget, Langstakken, Innkjegla, Dalkjegla mbrs; K1, Apt-Alb; 4, 19. *~ Carronelva Mbr (Cutbill & Challinor 1965) Minkinfjt Fm; C2, Mos; 4, 17. Cavendishryggen Mbr (Harland & Wilson 1956, Harland et al. 1966) Kingsbreen Fm; Rheanuten+Bl~nuten beds; Neoptz; 7, 12. t Celsiusberget Gp (Flood et al. 1969) Murchison Bay Spgp; Raudstup-Salodd, Norvik, Flora fms; Neoptz; 6, 12. t Chamberlindalen Fm (Harland 1978; Harland et al. 1993) Konglomeratfjellet Gp; (eastern equiv, of Dunderdalen Fm); V, Varl; 10, 13. *t Charlesbreen Sbgp (Dineley 1958) Gipsdalen Gp; Scheteligfjt, Broggertinden, T~trnkanten; Petrellskaret fms; C2, Bsh-Mos; 4, 17. Chydeniuslbreen] Granite (Harland 1959) SD; 7 t Claraia zone (Frebold 1936) ,-~lower Vardebukta Fm; Trl; 4, 18. t Coal-bearing sst. f m (Kotlukov 1936),~ Firkanten Fro. t Colesbukta Fm (Livshits 1967)~ Basilika Fm; Pg; 4, 20. t Collinderodden Fm (Livshits 1967)~ Battfjellet Fro; Pg; 4, 20. t Coloured oolitic horizon (Wilson 1961) in upper part of Lower Backlundtoppen Fro; Neoptz; 7, 12, 13. t Comfortlessbreen Gp (Harland 1960; Harland et al. 1993), Aavatsmarkbreen, Annabreen, Haaken fms; V1, Var2; 9, 13. ~- Conqueror[fjelletl Fm (Atkinson 1960; Harland et al. 1979) Grampian Gp; ?O--S; 9, 14. t Continental series (Rozyicki 1959) ~ Helvetiafjellet Fm. t Conwaybreen Fm (Challinor in Harland et al. 1966) ~ gneisses in basal (Nielsenfjellet Fm) in Kongsvegen Gp; Neoptz; 9, 12, 13. t Cora Limestone (Andersson 1900),-~Hambergfjellet Fm; P1, Art; 4, 17. t Cretaceous Shale (Hagerman 1925)~ Innkjegla Mbr; Kl; 4, 19. t Culm sandstones (Nathorst 1910) Billefjorden Gp; D3-C1, FamVis; 4, 11, 17. t Cyathopyllum limestones (Nordenski61d 1875) Minkinfjellet, Wordiekammen and Gipshuken fins; C2-P1: Mos-Art; 4, 17. t Dahlbreen Fm (of Wilson in Harland 1960)=Alkhorn Fm. :~t Dalkjegla Mbr (Parker 1967) Carolinefjellet Fro; K1, Apt-Alb; 4, 19. t Daonella layers, Niveau (Wiman 1910)~ lower Tschermak fjellet + Botneheia fms; Tr2_3; 4, 18. t Daonella 1st (Mojsisovics 1886) ~ Daonella layers t Dark grey to black shale fro (Kotlukov 1936)~ Basilika Fm Dartboard dolostone (Wilson 1961) part of old Gropbreen Series now in Backlundtoppen Fm. Daudmannsodden Fm (Ohta 1985) ? = Moefjellet Fm. ~t De Geerdalen Fm (Buchan et al. 1965) Kapp Toscana Gp; Iversenfjellet Mbr in Hopen, Tr3; 4, 18. t Deilegga Gp (Birkenmajer 1958) Bergskardet, Bergnova, Tonedalen fms; V; 10, 13. ~f Deltadalen Fm (Mork et al. 1982)=Vardebukta Fm in E. Spits.; Trl; 4, 18. :~ Deltadalen Mbr (Mork et al. SKS = Vardebukta Fm of Buchan et al. 1965). t Dense thick-flaggy plant-bearing sst f m (Kotlukov 1936)~ Battfjellet Fro. t Dentalienschichten (Nathorst 1910),-~Carolinefjellet Fm; K1; 4,19. t Diabaspynten division (Harland 1978)~ basites in L~tgneset Fro; V, Varl; 10, 13. t

466

STRATIGRAPHIC GLOSSARY

* Dickson Land Sbgp (SKS 1996) Gispdalen Gp; Gipshuken, Wordiekammen fms; C1-P2, Mos-Art; 4, 17. t Dicksonfjorden (sst) f m (Friend 1961)~1ocal Keltiefjellet, Stordalen division. t Diflovtoppen Mbr (Swett 1981) Tokammane Fm; El; 7, 14. t Ditrupa Layers (Stolley 1912) = Dentalien Schichten of Nathorst 1910 ~ upper part of CarolinefjeUet Fm. t Ditrupa Shale Series (Rozicki 1959)~Carolinefjellet Fro; K1; 4, 19. t Djevleflota Fm (Ohta 1982, Gee & Teben'kov 1996) lowest fm in Franklinsundet. in central Nordaustlandet. ?equivalent to Meyerbukta Fm in west; Neoptz; 6, 12. Dolostone mbr (Harland 1978) middle division of Fannytoppen Fm. t Dolomites and limestones at Forlandsundet (Orvin 1934)~ St Johnsfjorden Gp. Dordalen Fm (Bjornerud 1990) Nordbukta Gp; Ptz; pre-V; 10, 12. t Draken Fm (Harland & Wilson 1956) Akademikerbreen Gp; Neoptz; 7, 12. t Dracoisen Fm (Harland et al. 1966) Polarisbreen Gp; 6mbrs: D6, U. Dolomitic ShSst; D5, M. Dolost.; D4, M. Dolomite Sh. sst; D3, Black paper Shale; D2, Impure Carbon.; D1, Basal Dst; Vend, ?Edi; 7, 13. * Drevbreen Beds (Nysaeter 1977)~Treskelodden Fro; CrP2; 4,17. t Drevbreen Fm (Birkenmajer 1977)~Botneheia+Tschermakfjellet fins. t Dronbreen Bed (Dypvik et al. 1991) Oppdalen Mbr; J2, Bth; 4, 19. t Dunderbukta Fm (Krasil'shchikov & Kovaleva 1976)~ Dunderdalen Fm ~ ? Deilegga Fm. t Dunderdalen Fm (Craddock et al. 1985, Harland et al. 1993) Konglomeratfjellet Gp; (w. equiv, of Chamberlindalen Fm); V, Vary; 10, 13. t Dundrabeisen Fm (Harland et al. 1993) Kapp Lyell Gp; 4 unnamed mbrs as described by Cradock et al. 1985, and on map (Dallmann et al. 1990) V, Var2; 10, 13. t Dun6rfjellet Mbr (Smith et al. 1976) Kongsoya Fm (in Svenskoya); ?J2 3 ?K1; 5, 19. ]- Duneyane Fm (Birkenmajer 1972) - at Dunoyane; Neoptz; 10, 12. Duneyane mbr of H6ferpynten Fm (Birkenmajer 1972) t Dnsken Fm (Birkenmajer 1959) Sofiekammen Gp; Ol; 10, 14. l- Duvefjorden Cpx (Teben'kov in Gramberg et al. 1990) gneiss with granite veins & dykes, Nordenski61d 1863; granites and gneisses of Sandford 1926; migmatites and synorogenic rocks of Flood et al. 1969; Metamorphic Cpx of Krasil'shchikov (1973). t Eastern shales + quartzites (Fairbairn 1933) ~ Veteranen Gp. Ebbabreen sandstone, shale beds (Holliday & Cutbill 1972) facies in Ebbaelva Mbr; C2, Bsh; 4, 17. *t Ebbadalen Fm (Cutbill & Challinor 1965) Campbellryggen Sbgp; Odellfjellet, Trikolorfjellet, Ebbaelva mbrs; C2, Bsh-Mos; 4, 17. * Ebbaelva Mbr (Johannessen & Steel 1972) Ebbadalen Fm; C2, Bsh; 4, 17. t Edgeoya Fm (Lock et al. 1978) Kapp Toscana Gp (in Barentseya & Edgeeya); Tr2; Lad-Crn; 5, 18. *~ Efuglvika Mbr (Worsley & Edwards 1976) Kapp K~re Fro; C2, Mos; 11, 17. Eimfjellbreane Fm (Czerny et al. 1993) Eimfjellet Gp; Ptz; 10, 12. t Eimfjellet Gp (a) (Birkenmajer 1958, 1992) Vimsodden Subgp + Skhlfjellet Subgp + Gulliksenfjellet + Steinvikskardet fms; Ptz; 10, 12, 13. t Eimfjellet Gp (b) (Czerny et al. 1993) Pyttholmen, Gulliksenfjellet, Bratteggdalen, Skhlfjellet, Eimfjellbreane + Skjerstranda fins; Ptz; 10, 12. t Einsteinfjellet Mbr (Harland et al. 1966) Eskolabreen Fm; Paleoptz; 7, 12. t Elatides layers (Nathorst 1910, Hoel & Orvin 1937) ~ 3 m strata overlying Festningen sst in type section. Elbobreen Fm (Harland et al. 1966) Polarisbreen Gp; 4mbrs: E4 Slangen; E3, MacDonaldryggen; E2, Petrovbreen; El, L. Carb.; Vend; Varl; 7,13.

t

Elsabreen (conglom) beds (Cutbill & Challinor 1965)~Odell-

fjellet Mbr; C2, Bsh-Mos; 4, 17. t Elveflya Fm (Birkenmajer 1992/3) Vimsodden Subgroup; Skoddebukta, middle, Vimsa mbrs; V; 10, 13. *t Endalen Mbr (Steel et al. 1981) Firkanten Fm; Pg, Pal; 4, 20. Engelskbukta fm ? ~ Haaken Fm in Engelskbukta Gp. (?unpublished). t Enpiggen Mbr (Harland & Wilson 1956) Oxfordbreen Fm; Neoptz; 7, 12. t Erikbreen Mbr (Harland 1985 from Gee) Lerneroyane Fro; Ptz; 8, 12. t Escarpment Shales (Gregory 1921)~ Botneheia Fro; Tr2; 4, 18. Eskolabreen Fm (Harland & Wilson 1956) Finnlandveggen Gp; Einsteinfjellet, Lemstr6mfjellet, Malmgrenfjellet, Sederholmfjellet mbrs; Paleoptz; 7, 12. t Ester Seam (Orvin 1934) Kongsfjorden Fm, Kolhaugen Mbr; Pg, Pal; 9, 20. t Estheriahaugen mbr (Friend 1961) Mimer Valley Fm; D2-D3, Eif-Frs; 8, 16. [SKS to reject] t Eutomoceras horizon (Frebold 1931) ~ lower Botneheia Fm; Tr2; 4, 18. Evafjellet Fm (Bjernerud 1990) Nordbukta Gp; Ptz; pre-V; 10, 12. t Evaporite series (Bates & Schwarzacher 1958) parts of Wordiekammen and Gipshuken Fms; C2-P1, Kas-Art; 4, 17. t Fannypynten Fm (Harland 1978) Sofiebogen Gp; V, Var2; 10, 13. t Fannytoppen Fm (Birkenmajer 1972; Harland 1978) Sofiebogen Gp; Pisolitic, Dst & Lst mbrs; V; 10, 13. t Fardalen Schichten (Vonderbank 1970) ~ Frysjaodden + Battfjellet Fms; Pg; 4, 20. t FeiringoCjellet Fm (Challinor in Harland et al. 1966)~ Nielsenfjellet Fro. t Femmilsjeen Mbr (Harland et al. 1966) Bangenhuk Fro; includes Camryggen Gneiss; Paleoptz; 7, 12. t Ferrier[piggen] Gp (Tyrrell 1924, Atkinson 1960, Harland et al. 1979) Neukpiggen, Peterbukta, Hardiefjellet, Isachsen fms; V; 9, 13. t Ferrier Peak Series (Tyrrell 1924)~ Ferrier Gp etc; ?V; 9, 13. [Ferrierpiggen]. ~t Festningen Mbr (Nathorst 1913, Parker 1967) Helvetiafjellet Fm; Kl, Brm; 4, 19. *t Finlayfjellet Bed (SKS 1996) ~ Limestone B of Gee et al. 1953); Pj, Sak; 4, 17. t Finnlandveggen Gp (Harland & Wilson 1956) Atomfjella Cpx in Stubendorffbreen Spgp; Smutsbreen+Eskolabreen Fms; Paleoptz; 7, 12. *t Firkanten Fm (Major & Nagy 1964) Van Mijenfjorden Gp; Endalen, Kolthoffbreen, Todalen mbrs; Pg, Pal; 4, 20. t Fish Niveau (Wiman 1910)~ Lower Sticky Keep Fm; Trl; 4, 18. Fisherlagnna Fm (Harland et al. 1979) Peachftya Gp; V, ?Var; 9, 13. t Fiskeklofla Mbr (Friend 1961) Mimer Valley Fm; D3, Frs; 8, 16. t Fissile sst series (Nathorst 1910)~ Battfjellet Fro. t Fl~en Fm (Wallis 1969) Planetfjella Gp; 3mbrs: U, M + L ; Neoptz; 7, 12. t Flaggy sst series (Orvin 1940) ~ Battfjellet Fm. t Flakfjellet Mbr (Birkenmajer 1978) Bl~stertoppen Fm; ?El; 10, 14. t Fl~tan (granite) Fm (Johansson et al. 1995) Bleikfjellet Subgp; Harkerbreen Gp; Paleoptz, 7, 12. t Flatoyrdalen Mbr (Harland et al. 1966) Bangenhuk Fm; Paleoptz; 7, 12. t Flatsalen Mbr (Smith et al. 1975) Wilhelmoya Fm in Hopen; Tr3-Ja; Rht-?Het; 5-18. t Flogtoppane Mbr (Birkenmajer 1978) Vardepiggen Fro; El; 10, 14. Flora Fm (Kulling 1934) Celsiusberget Gp; Neoptz; 6, 12. [Floraberget]. t Floykalven Fm (Craddock et al. 1985, Harland et al. 1993) Konglomeratfjellet Gp; (w. equiv, of Gaimardtoppen Fm) V, Vary; I0, 13. t Foldnutane (Harland 1978) in Gaimardtoppen fm; V, Varl; 10, 13. t Forkdalen mbr (Murashov & Mokin 1976) Grey Hoek Fm; Da, Elf; 8, 16. (SKS to reject).

STRATIGRAPHIC GLOSSARY t ForlandCpx (Harland et al. 1979) Grampian, Scotia, Peachflya, Grikie, Ferrier gps; S-V; 9, 13, 14. [Prins Karls Forland]. t Forland f m (Orvin 1934; Krasil'shchikov 1973)~Trondheimfjella Fm. t Forland gp (Barbaroux 1966)?~ Forland Cpx. t Forlandsundet gp (Harland 1969)~Buchananisen Group replaced because Forlandsundet Graben (Harland 1969). * Fortet Mbr (Dallmann 1993) Minkinfjellet. Fm; C2, Mos; 4, 17. t Fosse Sandstone (Lundgren 1887) ~ De Geerdalen Fm; Tr3; 4, 18. t Fraenke|ryggen Fm (Kiaer 1916) Red Bay Gp; D1, Lok; 8, 16. t Franklinsundet Gp (Flood et al. 1969) Murchison Bay Spgp; Kapp Lord, Westmanbukta, Persberget, Meyerbukta fms; Neoptz; 6, 12. Fruholmen Fm (Worsley et al. 1988) Realgrunnen Gp; Krabbe, Reke and Akkar mbrs in Hammerfest Basin; correlates with lowest Wilhelmoya Fm. *~ Frysjaodden Fm (Livshits 1967) Van Mijenfjorden Gp; Bjornsonfjellet, Gilsonryggen, Hollendardalen mbrs; Pg; 4, 20. t Fugle subformation (Pavlov et al. 1983) ~ Tunheim Mbr; D3-C1, Fam-Tou; 11, 17. Fuglen Fm (Worsley et al. 1988) Adventdalen Gp; Hammerfest Basin; J3, Clv-Oxf. t Fuglhuk[en]Fm (Atkinson 1960; Harland et al. 1979) Grampian Gp; ?O-S; 9, 14. [Fuglhuken]. t Fulmarberget Mbr (Harland & Wilson 1956) Oxfordbreen Fm; Neoptz; 7, 12. Fuhrmeisterstranda fm Pg. in N. Prins Karls Forland (unpubl.?). t Fusulina limestone (Andersson 1900) Kapp Dun6r Fm; C2-P1, Gze-Art; 11, 17. t Fusulinagestein (G6es 1884; Nathorst 1910)~Brucebyen Beds of Wordiekammen Fm. Gaimardtoppen Fm (Harland 1978; Harland et al. 1993) Konglomeratfjellet Gp; (e. equiv, of Floykalven Fro) V, Varl; 10, 13. t GaloistoppenMbr (Harland et al. 1966) Kingbreen Fm; 2 divs; Neoptz; 7, 12. t Gangpasset granitization zone (Birkenmajer & Narebski 1960) facies in Sk~lfjellet Fm. t Gangpasset Mbr (Birkenmajer & Narebski 1960, B1992, Birkenmajer 1992) Sk~lfjellet Fm; Ptz; 10, 12. t Gangpasset migmatite f m (Birkenmajer 1975)~facies in SkS1fjellet Fro. Garwoodtoppen beds late in Svenskegga mbr. in S. Haakon VII Land [unpubl.]. t G~sbreenMbr (Birkenmajer 1978) Bl~stertoppen Fro; ?El; 10, 14. t G~shamna Fm (Major & Winsnes 1955, Birkenmajer 1992) Sofiebogen Gp; U, M + L divisions; cf Bogstranda unit in N; ?V, Edi; 10, 13. Geddesflya Fm (Harland et al. 1979) Grampian Gp; ?O-S; 9, 14. t Geebreen mbr ~ in Wilsonbreen Fm. t Geikie[breane] Gp (Atkinson 1960; Harland et al. 1979) Rossbukta, Gordon fms; V; 9, 13. t Generalfjella Fm (Gee & Hjelle 1966) Krossfjorden Gp; Ptz; 8, 12. Gerardodden (volcanic) (this work) the lower fm defining the Kapp Hansteen Gp and comprising mainly pyroclastic and sedimentary units; Neoptz; 6. *t Gerritbreen Beds (Cutbill & Challinor 1965) Cadellfjellett. Mbr; C2, Kas; 4, 17. Gerritelva sandstone mbr (Holliday & CutbiU 1972)~ Ebbaelva Mbr; C2, Bsh; 4, 17. Gilsenryggen Fm (Major & Nagy 1964) degraded to mbr and included with Ho|lenderdalen & Bjornsonfjellet mbrs in Frysjaodden Fm; Pg, 4, 20. *t Gilsonryggen Mbr (Major & Nagy 1972) Frysjaodden Fm; Pg; 4, 20. t Ginkgo Layers (Nathorst 1910; Hoel & Orvin 1937)~in Helvetia Fm. *t Gipsdalen Group (Cutbill & Challinor 1965) Bfinsow Land Spgp; Dickson Land, Campbellryggen, Charlesbreen, Treskelan sbgps and Kapp Dun6r, Kapp Hanna, Kapp Kfire, Landnordingsvika, Malte Brunfjellet, Harbardbreen fins; C1-P1, Spk-Art; 4, 11, 17.

467

*t Gipshuken Fm (Cutbill & Challinor 1965) Dickson Land Sbgp; Bredsdorffberget, Templet, Vengeberget, Kloten, Sorfonna, Zeipelodden mbrs; P1, Sak-Art; 4, 17. t Gjelsvikfjellet mbr (Murashov & Mokin 1976) Grey Hoek Fm; D2, Elf; 8, 16. (SKS to reject) t Glasgowbreen Fm (Harland & Wilson 1956, Harland et al. 1966) Veteranen Gp; 4mbrs: U. Greywacke, U. Qi; L. Greywacke; L. Qi; Neoptz.; 7, 12. t Glitrefjellet Mbr (Parker 1967) Helvetiafjellet Fm; K1, Brm-Apt; 4, 19. t Gn~lberget Fm (Birkenmajer 1959) Sofiekammen Gp; 4;-O; 10, 14. t Gneiss with granite veins and dykes in Nordaustlandet (Nordenski61d 1863) ~ Duvefjorden Cpx. t Goi~sbreenMbr (Birkenmajer 1978) Wiederfjellet Fm; Ol; 10, 14. t Goniodiscus nodosus horizon (Frebold 1929, 1930)~lowest nodule beds of Gregory 1921 ~ Sticky Keep Fm. Gordon[pynten] Fm (Atkinson 1960; Harland et al. 1979) Geikie Gp; V, Var2; 9, 13. t Gotia Gp (Krasil'shchikov 1967) Hinlopenstretet Spgp; Sparreneset, Klackbergbukta, Sveanor, Backaberget fms; V-GO; 6, 13. [Gotiahalvoya] t Grdhuken series (Murashov ?)~ Grey Hoek Fro. t Grdkallen Fm (Major & Winsnes 1955)~Ordovician units of Sorkapp Land: Tsjebysjovfjellet, Rasstupet, Nigerbreen, Hornstulloden units; 10, 14. t Grampian Gp (Tyrrell 1924; Harland et al. 1979) Geddesflya, Fuglhuk, Barents, Conqueror, Utnes fms; ?O-S; 9, 14. [Grampianfjella] t Granite and gneiss in Nordaustlandet (Sandford 1926)~ Duvefjorden Cpx. t Gravsjoenunit (Harland et al. 1993) LSgnesbukta Gp; V, Varl; 10, 13. Green sandstone f m (Orvin 1934)~Broggerbreen Fm in NyAlesund Subgp. t Green sandstone series (Nathorst 1910) ~ Hollendardalen Mbr + Grumantbyen Fm. t Greenish-grey dense sandstone f m (Kotlukov 1936)~Grumantbyen Fm. t Grey Hoek Fm (Holtedahl 1914; Friend et al. 1966) Andr~e Land Gp; Forkdalen, Tavlefjellet, Gjelsvikfjellet, Skamdalen, ?Verdalen mbrs; D2, Eif; 8, 10, 16. Grey sandstone f m (Orvin 1934)~Kongsfjorden Fm in NyAlesund Sbgp. t GrippiaNiveau (Wiman 1928) ~ upper Sticky Keep Fm; Trl; 4, 18. * Gronfjorden Bed (Steel in Ohta et al. 1992) bed within Todalen Mbr: Pg, Pal; 4, 20. t Gropbreen Mbr (Harland, Hambrey & Waddams 1993) Wilsonbreen Fm (W3); Vend., Var2; 7, 13. t Grumant Fm (Livshits 1967)= Grumantbyen Fm; Pg; 4, 20. * Grumantbyen Fm (Livshits 1967; Steel et al. 1981) Van Mijenfjorden Gp; Pg; 4, 20. Grumantdalen Schiehten (Vonderbank 1970) ~ Basilika + Grumantbyen + Hollendardalen Fms; Pg, 4, 20. t Grumantdalen-Schichten (Vonderbank 1970)~ his second Paleogene sedimentation cycle in Central Basin~ Battfjellet, Grumantbyen fms + Hollendardalen Mbr. t Grusdievbreen Fm (Harland & Wilson 1956) Akademikerbreen Gp; 2mbrs: U (Pale) Mbr with 6 beds, L (dark) Mbr with 4 beds; Neoptz; 7, 12. t Gulliksenfjellet Fm (Birkenmajer 1958, 1992) Eimfjellet Gp; Ptz; 10, 12. Gullichsenfjelletfm = Gulliksenfjellet Fm t Gymnotoceras horizon (Frebold 1913) ~ upper Botneheia Fm; Tr2; 4, 18. t Gypsum beds (Nathorst 1910)~Gipshuken Fm; P1, Sak-Art; 4, 17. t Gypsum mbr (Bates & Schwarzacher 1958)~Vengeberget Mbr; P~, Sak; 4, 17. t Haaken Fm (Harland et al. 1979) Comfortlessbreen Gp; [the upper tillite] V, Var2; 9, 13. [Haakentoppen and Haakenbreen].

468 t

* t t

*t t t

*t t ~t t

t

t

~t

* *t t

J;

*t t *t

t t t *t t

STRATIGRAPHIC GLOSSARY

Hahnfjella Fin (Pchelina 1980, 1983) Kapp Toscana G p =

Carnian deposits of Svalbard. Haitanna Mbr (Dallmann et al. 1993) Adriabukta Fm; C1, Tou-Vis; 9, 17. Halobia limestone (Noetling 1903)~ Tschermakfjellet Fm. Halobia zitteli bed (Moysisovichs 1886) ~ lower zone of Halobia lst.and below H. cf. meumayri subzone. Hambergfjellet Fm (Worsley & Edwards 1976) Biinsow Land Spgp; P~, Art; 11, 17. Hannabreen (sst) mbr. ~ Buchananhalvoya Mbr Hansbreen Mbr (Birkenmajer 1978) Nordstetinden Fm; E-O; 10, 14. Hansbreen tilloid (Harland 1978) = Hansvika Fm Hansvika Fm (Harland et al. 1993) Sofiebogen Gp; V, Varl; 10, 13. Hhrbardbreen Fm (Cutbill & Challinor 1965) Gipsdalen Gp; C2, Mos; 5, 17. Hardiefjellet Fm (Harland et al. 1979) Ferrier Gp; V, Var2; 9, 13. Hhrfagrehaugen Mbr (Smith et al. 1976) Kong Karls Land Fm (in Kongsoya); K1, Brm-Apt; 5, 19. Harkerbreen Gp (Harland & Wilson 1956; Harland et al. 1966, 1992) Atomfjella Cpx; Tordenryggen+Bleifjellet Subgroups; Paleoptz; 7, 12. Havert Fm (Worsley et al. 1988); lower unit of Ingoydjupet Gp in Hammerfest Basin. Hecla Hoek Complex (Nordenski61d 1863; Harland & Wilson 1956; Harland et al. 1992) Upper, Middle and Lower Hecla Hoek (Harland & Wilson 1956); Hinlopenstretet, Lomfjorden and Stubendorffbreen Spgps; Pt2-4~-O1_2; 6, 7, 12, 13, 14. Heiroglyphic series (Rozyicki 1959) an Early Triassic facies in S. Spits. Hekkingen Fm (Worsley et al. 1988) Adventdalen Gp; Krill and Alga mbrs; Hammerfest Basin; J3, Oxf-Tth. Helvetiafjellet Fm (Parker 1965, 1967) Adventdalen Gp; Glitrefjellet, & Festningen mbrs; K1, Brm-Apt; 4, 19. Helvetsflaya Fm (Gee & Teben'kov 1996) Brennevinsfjorden Gp in central Nordaustlandet. Ptz; 6, 12. Hinlopenstretet Spgp (Harland et al. 1966); Hecla Hoek Cpx; Oslobreen, Polarisbreen, Gotia gps; V-~O; 6, 7, 14. Hjelmen Mbr (Dallmann et al. 1993) Hyrnefjellet Fm; C2, Bsh-Mos; 10, 17. Hoelbreen Mbr (Cutbill & Challinor 1965) Horbyebr. Fm; C1, Tou; 4, 17. H6ferpynten Fm (Major & Winsnes 1955; Birkenmajer 1972) correlation questioned Harland (1978) six mbrs: Qi; Oolitic Lst; Wurmbrandegge, Andvika; Kvivodden U + L divisions; Neoptz; 10, 12. Hogsletta M b r (Mork et al. SKS from unpublished source possibly already named by Smith et al. 1976). Hollendardalen Fm (Livshits 1967) degraded to mbr as asst. in Gilsonryggen shales; Pg; 4, 20. Hollendardalen Mbr (Livshits 1967) Frysjaodden Fm, Pg; 4, 20. Holmesletfjella Fm (Harland 1960, Kanat & Morris 1986) Bullbreen Gp; 3mbrs: BH6, BH5 + BH4: ?S; 9, 14. Herbyebreen Fm (Cutbill & Challinor 1965) Billefjorden Gp; Hoelbreen, Triungen mbrs; D3-C1, Fam-Tou; 4, 17. Hornb~ekpollen Mbr (replaces Gee's Wulffberget Fm in Hjelle & Lauritzen 1982 because preoccupied) Lernereyane Fm; Ptz; 8, 12. Hornemanntoppen Batholith, S-D; 8. Hornnes Fm (Harland et al. 1979) Scotia Gp; V, ?Var; 9, 13. Hornstullodden Fm (Major & Winsnes 1955) Gp; upper part Luciapynten Dusken mbrs, lower part Wiederfjellet mbr; O1; 10, 14. Hornsund Spgp (Birkenmajer 1975) Sorkapp Land, Sofiekammen gps; E-O; 10, 14. Hornsundneset Fm (Siedlecki 1960) Billefjorden Gp; C1, Vis; 10, 17. Hornsundtind Fm (Birkenmajer 1975) Sofiekammen Gp; Sjdanovfjellet, Tsjebysjovfjellet; Rasstupet mbrs; O1; Can3; 10, 14. Hotellneset mbr (?) in Upper Firkanten Fm in Nordenski61d Land; Pg, Pal.

*t Hovtinden Mbr (Cutbill & Challinor 1965) Kapp Starostin Fm; P2, Gua; 4, 17. *t Hultberget Fm (Cutbill & Challinor 1965) Campbellryggen Sbgp; C1_2, Spk-Bsh; 4, 17. t Hunnberg Fm (Kulling 1934) Raoldtoppen Gp; Neoptz; 6, 12. [Hunnberget]. t Hustedia 1st (Nathorst 1910)N Retzia Lst~ u Vardebukta Fm. *t Hyrnefjellet Fm (Birkenmajer 1959) Treskelen Sbgp; Bladegga, Brattberget, Hjelmen mbrs; C2, Bsh-Kas; 10, 17. t Hyrnefjellet Fm (Pchelina 1980, 1983)~Botneheia Fm=Anisian deposits in S. Spits. *t Idunfjellet Mbr (Lauritzen 1981) Wordiekammen Fm; C2-P1, Mos-Sak; 5, 17. t Ingebrigtsenbukta Series (Rozicki 1959; Birkenmajer 1975)N Agardhfjellet Fm; J; 4, 19. Ingebrigtsenbukta Mbr (Rozicki 1959; Mork et al. SKS as lower Agardfjellet Fm in west). Ingeydjupet Gp (Worsley et al. 1988) Kobbe, Klappmyss and Havert fms; Hammerfest Basin; Trl-Tr2; 18. Ingstadsegga eonglom. (Hellman et al. 1997) basal conglomerate of Polhem Fm. Ptz; 7. ~t Innkjegla Mbr (Parker 1967) Carolinefjellet Fm; K1, Alb; 4, 19. t Innvikhogda Fm (Ohta 1982)~ upper Austfonna Gp Instrumentberget (granite) Fm (Johansson et al. 1995) Bleikfjellet Subgp, Harkerbreen Gp; Paleoptz; 7, 12. t Isaehsen Fm (Harland et al. 1979) Ferrier Gp; V, Var2; 9, 13. t Isbjernhamna Gp (Birkenmajer 1958, 1992) Revdalen, Ariekammen, Skoddefjellet fms; Ptz; 10, 12. t Isfjorden Fm (Pchelina 1980, 1983) Kapp Toscana Gp =Early Norian age deposits of Spits. & Hopen. lskantelva Mbr (Birkenmajer 1993) Tonedalen Fm; V, Varl; 10, 13. J;t lskletten Mbr (Buchan et al. 1965) Sticky Keep Fm; Trl, ?Nml; 4,18. t Iversenfjellet Mbr (Smith 1975) De Geerdalen Fm in Hopen; Tr2_3, Nor-?Rht; 5, 18. :~t Jannsfjellet Subgp (Parker 1967) Adventdalen Gp; Rurikfjellet +Agardhfjellet fms; J2-K1, Bth-Brm; 4, 19. Jemtdlandryggen beds (?) Svenskeegga Mbr in SE Oscar II Land; P 1; ?Kun. Jens Erikfjellet Fm (Birkenmajer 1991) Vimsodden Subgp; V; 10, 13. t Johnsenberget mbr (Smith et al. 1976) informal upper division of Kongsoya Fm at Johnsenberget in E Kongsoya. Josefine Seam (Orvin 1934) Broggerbreen Fm, Tvillingvatnet Mbr; Pg, Pal; 9, 20. t Jotunfonna beds (Cutbill & Challinor 1965) fusuline zone~ Kapitol Mbr; C2; 4, 17. t Julhogda Mbr (Dallmann et al. 1993) Adriabukta Fm; C1, Tou; 10, 17. t Jura-basis cgl (Frebold 1928) ~ Brentskardhaugen Bed. t Jutulslottet Mbr (SKS 1996) TArnkanten Fm; C2, Mos; 9, 17. Kattieyra complex (Ohta et al. 1996, this work) meta-dolostones in shear zone in eastern Forlandsundet; ?O. Kaffioyra f m ,,~ Paleogene of Oscar II Land. t Kaggen Fm (Harland et al. 1979) Scotia Gp; V, Edi; 9, 13. ~t Kaosfjellet Mbr (Buchan et al. 1965) Sticky Keep Fro; Trl; Spa; 4, 18. Kap Sparre Fm (Kap Sparre-formationen of Kulling 1932)= Cape Sparre (Kulling 1934)= Sparreneset + Klackbergbukta fms. *t Kapitol Mbr (Cutbill & Challinor 1965) Wordiekammen Fm; C2, Mos-Gze; 4, 17. Kapp Berg Fm (Bjernerud 1990) Nordbukta Gp; Ptz; preV; 10, 12. *t Kapp Dun~r Fm (Krasil'shchikov & Livshits 1974) Gipsdalen Gp; C2-P1, Gze-Ass; 11, 17. ~f Kapp Fanshawe Fm (Nordenski61d 1863)~ Billefjorden & Gipsdalen gps near Lomfjorden; C-P; 5, 17. *~ Kapp Hanna Fm (Krasil'shchikov & Livshits 1974) Gipsdalen Gp; C2, Mos-Kas; 11, 17.

STRATIGRAPHIC GLOSSARY t Kapp Hansteen Gp (Kulling 1934, Flood et al. 1969) Norgekollen, Gerardodden and Svartrabbane fms; Ptz; 6, 12. * Kapp Harry Mbr (SKS 1996) Nordkapp Fm; C1, Tou-Vis; 11, 17. *t Kapp Kfire Fm (Worsley & Edwards 1976) Gipsdalen Gp; C2, Bsh-Mos; 11, 17. Kapp Kjeldson Division (Foyn & Heintz 1943) Wood Bay Fm; D1, Pra; 8, 16. t Kapp Koburg Mbr (Worsley & Heintz 1977) Wilhelmoya Fm in Kongsoya; Tr3, Nor-Rht; 5, 18. *t Kapp Levin Mbr (Worsley & Edwards 1976) Roedvika Fm; D3; Fam; t Kapp Linn~ Fm (Hjelle 1962; Harland et al. 1993) V, Var2; 10, 13. t Kapp Lord Fm (Flood et al. 1969) Franklinsundet Gp; Neoptz; 6, 12. t Kapp Lyell beds (Semevskiy 1967)~ rest on Late Pleistocene Bellsund beds. t Kapp Lyell Gp (Harland 1978; Hjelle 1979; Harland et al. 1993) Lyellstranda, Logna, Dundrabeisen fms= 10 unnamed map units in Dallmann et al. (1990); V, Var2; 10, 13. t Kapp Martin Fm (Hjelle 1969; Harland et al. 1993) Lfignesbukta Gp; V, Vara; 10, 13. t Kapp Platen Fm (Flood et al. 1969) in E Brennevinsfjorden Gp; Ptz; 6, 12. t Kapp Sparre Fm (Krasil'shchikov 1965) ~ Sparreneset Fm; ~ - O ; 6, 13 (replaced because confusion with Kap Sparre-formatiohen = Cape Sparre = Sparreneset + Klackbergbukta fms). *t Kapp Starostin Fm (Cutbill & Challinor 1965) Tempelfjorden Gp; Selanderneset, Hovtinden, Revtanna, Stensi6fjellet, Palanderbukta, Svenskeegga, Voringen mbrs; P1 2: Art-Gua; 4, 17. t Kapp Toseana Gp (Buchan et al. 1965) Wilhellnoya, De Geerdalen, Tschermakfjellet, Austjokelen and Skuld fms; Try3; 4, 18. (Mork et al. SKS. recommend replace by Storfjorden Gp comprising De Geerdalen, Tschermakfjellet, Skuld, and Snadd fms and excluding Wilhelmoya Fm.) ~f Kapp Ziehen unit (Lock et al. 1978)~Kapp Starostin Fm in Barentsoya; P ; 5, 17 (in this work = mbr in Kapp Starostin Fm). ~t Karentoppen Mbr (Mork et al. 1982) Botneheia Fm (in S); Tr2; 4,18. t Keilhaufjellet Fm (Pchelina 1980, 1983) Kapp Toscana Gp ~ Tr3 in S Spits; 4, 18. t Keltiefjellet Division (Friend 1961) Wood Bay Fm; ~ Lykta Div. D1, Pra-Ems; 8, 16. Kerr Gp (Atkinson 1960)~Peachflya Gp; V; 9, 13. *t Kiaerfjellet beds (Cutbill & Challinor 1965) Tyrrellfjellet Mbr; P1, Sak; 4, 17. t Kikutodden mbr (Pchelina 1983)~lower part of Helvetiafjellet Fm in SE Sorkapp Land. t Kingbreen Fm (Harland et al. 1966)=M. Veteranen Series of Harland & Wilson (1956); Veteranen Gp; Cavendishryggen, Bogen, Galoistoppen mbrs; Neoptz; 7, 12. t Kirtonryggen Dolomites (Gobbett & Wilson 1960)= Dolostone Member of Kirtonryggen Fro. t Kirtonryggeu Fin (Harland et al. 1966): Oslobreen Gp; Nordporten, Basissletta, Spora mbrs; O1, Can; 7, 14. ;~t Kistefjellet Fin (Mork et al. 1982) Sassendalen Gp (in S) : Sticky Keep+part Vardebukta Fro, Brevassfjellet Bed; Trl; 4, 18. (Mork et al. SKS recommend K. Mbr in Vardebukta Fro) t Klackbergbukta Fm (Krasil'shchikov 1967) Gotia Gp; the lower five mbrs of Kulling's Cape Sparre Fm; Vend., ?Edi; 6, 13. t Klackberget Fm (Harland 1985; Harland et al. 1993)= Klackbergbukta Fro. :~ Klappmyss Fm (Worsley et al. 1988) middle unit of Ingoydjupet Gp in Hammerfest Basin. $ Klippfisk Fm (Mork et al. SKS. from unpublished work on Bjarmeland Platform; K1, Ber-vlg.) *t Kloten Mbr (Cutbill & Challinor 1965) Gipshuken Fm; P2, Sak; 4,17. t Knivoddeu Fm (Harland et al. 1979) Scotia Gp; V1, ?Var; 9, 13. ~t Knorringfjellet Mbr (Mork et al. 1982)~Wilhelmoya Fro, in main Spitsbergen Basin; Tr3, Rht; 4, 18.

469

Knurr Fm (Worsley et al. 1988) Adventdalen Gp; Hammerfest Basin; K1, Ber-Vlg. Kobbe Fm (Worsley et al. 1988) upper unit of Ingeydjupet Gp in Hammerfest Basin. *t Kobbebukta Mbr (SKS 1996) Kapp K~re Fm; C2, Mos; 11, 17. * Kolhaugen Mbr (SKS 1996) Kongsfjorden Fm; Pg, Pal; 9, 20. $ Kolje Fm (Worsley et al. 1988) Adventdalen Gp; Hammerfest Basin; K~, Hau. t Kollerbreen Cpx (Abakumov 1976) ~ ?upper part of Smeerenburgfjorden Cpx. Kolmule Fm (Worsley et al. 1988) Adventdalen Gp; Hammerfest Basin; K~, Brm-Alb. *t Kolthoffberget Mbr (Steel et al. 1981) Firkanten Fm; Pg, Pal; 4, 20. 1:t Kong Karls Laud Fm (Smith et al. 1976) Adventdalen Gp; Kukenthalfjellet + H~trfagrehaugen mbrs; K~, Brm-Apt; 5, 19. (Merk et al. SKS make it KKL Mbr in ?upper Helvetiafjellet Fm). Konglomeratfjellet Gp (Hjelle 1969; Harland et al. 1993); Dunderdalen, Chamberlindalen, Slettfjelldalen, Solhegda, Gaimardtoppen, Fleykalven, Thiisfjellet fms; V, Varl; 10, 13. t Konglomeratodden Mbr (Friend et al. 1997) Rivieratoppen Fm; Dl, Lok; 8, 16. t Kongressfjellet Sbgp (Buchan et al. 1965)~ Botneiheia + Sticky Keep fms. *t Kongsf]ordeu Fm (Livshits 1967) Ny-Alesund Sbgp; Tvillingvatnet, Morebekken, Kolhaugen mbrs; Pg, Pal; 9, 20. $~ Kongsoya Fm (Smith et al. 1976) Adventdalen Gp; Dun~rfjellet, Tordenski61dberget, Retziusfjellet + Passet mbrs; ?J1-K1; 5, 19. t Kongsvegen Gp (Harland et al. 1966) Bogegg, Steenfjellet, Nielsenfjellet, Mfillerneset fms; ?pre-Vend; 9, 13. Kontaktberget granite (Gee et al. 1995) Laponiahalvoya Gp; Ptz; 6, 12. t K o n u s s e n f m (Pchelina 1983)~lower Rurikfjellet Fro. t Kortbreeu Fm (Harland et al. 1966)=L Veteranen Series of Harland+Wilson (1956); Veteranen Gp; two divs: Qi, Lst; Neoptz, 7, 12. Krabbe Mbr (Mork et al. SKS, upper of three mbrs of Fruholmen Fm in Hammerfest Basin) Krill Mbr (Merk et al. SKS, upper of two mbrs of Hekkingen Fm in Hammerfest Basin). *t Krokodillen Fm (Livshits 1967) McVitiepynten Sbgp; Pg; 9, 20. t Krossfjorden Group (Abakumov 1976 extended here) Generalfjella, Signehamna, Nissenfjella + Lerneroyane Fm + Biskayerfonna Sbgps with Biskayerhuken + Montblane Fins; Ptz; 8, 12. Krossnya Fm (Lauritzen & Yochelson 1982 and this work) Hinlopenstretet Supergp. ~1, Bot; 14. t Kiikenthalfjellet Mbr (Smith et al. 1976) Kong Karls Land Fm (in Svenskeya); K1, Brm-Apt; 5, 19. Kutling Mbr (Merk et al. SKS: only mbr of Klippfisk Fm). t Kvalvdgen f m (Pchelina 1983) ~ upper four mbrs of Carolinefjellet Fm. $ Kveite Fm (Worsley et al. 1988) Adventdalen Gp; Hammerfest Basin; K2. Kvisla Mbr (Birkenmajer 1992, 1993) Nottinghambukta Fm; Ptz; 10, 12. Kvislodden Mbr (Birkenmajer 1992, 1993) Nottinghambukta Fro; Ptz; 10, 12. J; Kvitting Fm (Worsley et al. 1988) Adventdalen Gp; Hammerfest Basin; K2. t Kviveodden Mbr (Harland 1978) H6ferpynten Fm; U + L divisions; Neoptz; 10, 12. t Lfignesbukta Gp (Harland et al. 1993) L~gneset, Gravsjeen, L~tgnesrabbane, Kapp Martin fms; V, ?Vary; 10, 13. t Lfigneset Fm (Hjelle 1969; Harland et al. 1993) LAgnesbukta Gp; V1, Varl; 10, 13. t Ldgneset-Kapp Martin g r e y + g r e e n shales (Hjelle 1969)~base of Lagneset Fm Ldgnesflya Lst (Hjelle 1962) ~ Upper Lst. mbr of LAgnesrabbane Fm, Gravsjoen unit; L~tgneset Fm,+Malmberget unit; V, Varl; 10, 13. t Lfignesrabbane Fm (Hjelle 1969; Harland et al. 1993) LAgnesbukta Gp; V, Varx; 10, 13.

470 t

*t ~t

t * ]-

t

t

t t t

t t

t t

t

]t t t

t

t t

t t

STRATIGRAPHIC GLOSSARY

Laksvatnet Fm (Krasil'shchikov & Livshits 1974) ~ Miseryfjellet

Fm; P1-2; Art-Gua; 11, 17. Landnardingsvika Fin (Krasil'shchikov & Livshits 1974) Gipsdalen Gp; C2, Bsh; 11, 17. ?Landveggen gp (?) Langstakken Mbr (Parker 1967) Carolinefjellet Fm; K1, Alb; 4, 19. Laponiafjellet granite (Gee et al. 1995) Laponiahalveya Gp; Ptz; 6, 12. Laponiahalvoya Gp (this work) Kontaktberget, Laponiafjellet granites; Ptz; 6, 12. Lardyfjellet Mbr (Dypvik et al. 1991) Agardhfjellet Fm; J2-3, Clv-Oxf; 4, 19. Leinstranda fin (Barbaroux 1968)~ Scheteligfjellet Fro. Leirhaugen Mbr (SKS 1995) Breggerbreen Fro; Pg, Pal, 9, 20. Lemstriimfjellet Mbr (Harland et al. 1966) Eskolabreen Fm; Paleoptz; 7, 12. Lernerayane Fm (this work) Krossfjorden Gp; Pteraspistoppen, Erikbreen + Hornb~ekpollen mbrs; Ptz; 8, 12. Lias Conglomerate (Rozyicki 1959)~ Brentskardhaugen Bed; J2; 4, 19. Liefde Bay Supergp (Nordenski61d 1875; Nathorst map in Suess 1888; Friend et al. 1997); Andr6e Land, Red Bay, Siktefjellet gps; ?$4-D3, Pri-Frs; 8, 10, 16. Liefdefjorden Fm (Harland 1960, Hjelle & Lauritzen 1982 after Gee) preoccupied by Liefde Bay (Supergroup) so here Lernereyane Fm. Lilijeborgfjellet Fin (Murashov & Mokin 1976) Siktefjellet Gp; S4?Ol, ?Pri-Lok; 8, 16. Limestone A (Forbes et al. 1958)~ Veringen Mbr; P1, Art-Kun; 4, 17. Limestone B (Gee et al. 1952)~Finlayfjellet Beds; P1, Sak; 4, 17. Limestone mbr (Harland 1978), Lower div. of Fannytoppen Fm. Lindstroemi (sst) horizon (Frebold 1931)~ Somovbreen Mbr of Botneiheia Fm. Lingula sst. (Stolley 1911)~ in De Geerdalen Fm. Linn6fjella unit (Hjelle 1962; Harland et al. 1993) V, ? Var2; 10, 13. Lioplax layers (Nathorst 1897) Helvetiafjellet Fm, above Elatides layers and below Pityophyllum layers. Lipertoppen Mbr (Birkenmajer 1993) Tonedalen Fm; V, Varl; 10, 13. Logna Fin (Harland et al. 1993) Kapp Lyell Gp; V, Var2; 10, 13. Lomfjorden Supergp (Harland et al. 1966)= M. Hecla Hoek of Harland & Wilson (1956); Akademikerbreen+Veteranen gps; Neoptz; 7, 12. Longyear (coal) seam (Major & Nagy 1972); Firkanten Fm in NE Nordenski61d Land; Pg, Pal. Longyeardalen mbr (?) Firkanten Fm in N.E. Nordenski61d Land; Pg, Pal. Lavliebreen Fm (Harland et al. 1979) St Jonsfjorden Gp; 2 divisions not named (Harland et al. 1993) V1, Varl, 9, 13. Lower argillitefm (Livshits 1965)~ Basilika Fm. Lower coal-bearing series (Nathorst 1910)~ Firkanten Fro. Lower coal-bearing sst. f m (Lyutkevich 1937)~ Firkanten Fro. Lower coal Horizon (Orvin 1934)~ Kolhaugen Mbr of Kongsfjorden Fm. Lower dark shale series (Nathorst 1910; Lyukevitch 1937)~ Basilika Fm. Lower division of Marietoppen Fm (Murashov & Mokin 1976) cf. Wood Bay, Keltiefjellet Div. Lower dolomite mbr (Bates & Schwarzacher 1958)~ Ki~erfjellet Beds of Tyrrellfjellet Mbr of Wordiekammen Fm. Lower Gypsiferous Series (Gee et al. 1952)~Ebbadalen Fm minus Odellfjellet Mbr; C2, Bsh-Mos; 4, 17. Lower Gypsum Zone (Cutbill & Challinor 1965)~ Vengeberget Mbr; Pa, Sak; 4, 17. Lower Lamina Sandstone (Hagerman 1925)~Dalkjegla Mbr; K1; 4, 19. Lower light sst series (Orvin 1940)~ Firkanten Fm.

t

Lower Posidonia shales (Spath 1921)~ Iskletten Mbr of Sticky

Keep Fm. t

Lower Saurian Niveau (Wiman 1910)~upper Sticky Keep Fm;

Trl; 4, 18. t t

Lower transitionalfm (Livshits 1965)~ Hollendardalen Mbr. Lowest nodule beds (Gregory 1921)~ Sticky Keep Fro.

t Luciapynten Fm (Birkenmajer 1959) Sofiekammen Gp; O1; 10, 14. t Lyellstranda Fm (Harland 1978; Harland et al. 1979) Kapp Lyell gp; 5 unnamed 5-1 as described, e.g. Craddock et al. (1985); V, Var2; 10, 13. t Lykta Division (Feyn & Heintz 1943; Friend 1961) Wood Bay Fm; D1, Pra; 8, 16. Lyngebreen sequence (this work) for Dallmann et al. 1993 for map units 34, 35 + 36. Birkenmajer (1993) compared unit 34 with the H6ferpynten Fm; Ptz; 10, 12. t Lyngfjellet Mbr (Smith et al. 1975) Wilhelmeya Fm; in Hopen; Tr3-J1, Rht-?Het; 5-18. t Magdalenefjorden gneisses (Harland 1960)~Nissenfjella fm; Ptz; 8, 12. ]- Magnethogda Gp (Harland 1978; Dallmann et al. 1990) map units 49 + 50 + ?; Ptz; 10, 12. Malmberget unit (Harland et al. 1993) V, Var; 10, 13. t Malmgrenfjellet Mbr (Harland et al. 1966) Eskolabreen Fro; Paleoptz; 7, 12. Malte Brunfjellet Fm (SKS 1996) Gipsdalen Gp; C2, Mos; 5, 17. *t Marchaislaguna Fm (Livshits 1967) McVitiepynten Sbgp; Pg; 9, 20. :H- Marhogda Bed (Backstrom & Nagy 1985) Oppdalen Mbr; J2, Bth; 4, 19. t Marietoppen Fin (Friend et al. 1961) Andr~e Land Gp; upper, middle +lower divisions; DI 2; 10, 16. t Marstranderbreen Mbr (SKS 1995) Frysjaodden Fro; Pg; 4, 20. *t Mathewbreen Beds (Cutbill & Challinor 1965) Cadellfjellet Mbr; C2, Gze; 4, 17. MaeDonaldryggen Mbr (Harland, Hambrey & Waddams 1993) Elbobreen Fm (E3); Vend.; Varl; 7, 13. t McVitie Formation (Atkinson 1963)~McVitiepynten Subgp; Pg; 9, 20. t McVitiepynten Subgp (Atkinson 1963; this work) Buchananisen Gp; Aberdeenflya, Marchaislaguna, Krokodillen, Reinhardpynten, Sesshegda fms; Pg; 9, 20. Mefonntoppene units (this work) based on Dallmann et al. 1993 map units 37 and 38 who compared the rocks with facies in the Isbjornhamna Gp; Ptz; 10, 12. * Meranfjellet Mbr (Dallmann et al. 1993) Adriabukta Fm; C1, Tou-Vis; 10, 17. * Meyerbukta Fm (Ohta 1982) Franklinsundet Gp; Neoptz; 6, 12. Middle division of Marietoppen Fm (Murashov & Mokin 1976) cf. Wood Bay, Stjerdalen Div. Middle shale series (Hoel 1929)~ Frysjaodden Fro. t Midifjellet Mbr (Birkenmajer 1978) Vardepiggen Fm; El; 10, 14. Midterhuken unit (Harland 1978) ~ marbles + calc phyllites of Magnethegda Gp to S; Ptz; 10, 12. Migmatites and synorogenic granites of Nordaustlandet (Flood et al. 1969)~ Duvefjorden Cpx. t Millarodden tilloid unit (Harland 1978)~L~tgneset Fm in SE Nordenski61dkysten. t Mimer Valley Fm (Vogt 1928, 1940, Friend 1961); Andr6e Land Gp; Planteklefta, Planteryggen, Fiskeklefta, Estheriahaugen mbrs; Dz-D3, Eif-Frs; 8, 16. t Mimerbukta ssts (Friend 1961; Friend et al. 1966)~deformed Wood Bay § Mimer Valley fms. t Mimerdalen series (Vogt 1938)N Mimer Valley Fro; D2-3; 8, 16. *t Minkinfjellet Fm (Cutbill & Challinor 1965) Campbellryggen Sbgp; Fortet, Terrierfjellet; Carronelva mbrs; C2, Bsh-Mos; 4, 17. t Misery subfm (Pavlov et al. 1983) part of Vesalstranda Mbr of Roedvika Fm; D3, Fam; 11, 17. *t Miseryfjellet Fm (Worsley & Edwards 1976) Tempelfjorden Gp; Pa 2, Kun-Ufi; 11, 17.

STRATIGRAPHIC GLOSSARY t Moeqellet Fm (Wilson in Harland 1960; Harland et al. 1979) St Johnsfjorden Gp; 4 divisions not named (Harland et al. 1993) V1, Varx; 9, 13. ~t Mohnhogda Mbr (Smith et al. 1976) Wilhelmoya Fm in Svenskoya; Tr3-J1; Rht-?Sin; 5, 18. t Montblane Fm (Harland 1960; Hjelle & Lauritzen 1981 after Gee) Biskayerfonna Subgp; Ptz; 8, 12. * Morebekken Bed (SKS 1995) Kongsfjorden Fm; Pg, Pal; 9, 20. *t Morebreen Mbr (Cutbill & Challinor 1965) Wordiekammen Fm; Ca, Kas-Gze; 4, 17. Mosquensis Stufe (Holtedahl 1973) from Spirifer mosquensis, applied to Scheteligfjellet Fm; (C2, Mos); 9, 17. t Mosselbukta f m (Harland et al. 1992)=Polhem Fm Harkerbreen Gp.; Ptz; 7, 12 t Mossel(halvoya) Series (Krasil'shchikov 1973) --~northern outcrop of Planetfjella Gp. t Motalaqella Fm (Harland et al. 1979; VOD of Kanat & Morris 1986) Bullbreen Gp; with 5mbrs-see Chapter 9 include. BH2 + BH1; O; 9, 14. Mountain Limestone (e.g. Nordenski61d) an old name for (Early) Carboniferous limestones. In Svalbard) referred also to Ryss6 dolostone (Ptz). t M t Scotia series (Tyrrell 1924) ~ Scotia Gp; V; 9, 13. t Miillerneset Fm (Harland et al. 1979) Kongsvegen Gp; preVendian 9, 13. * Mumien Fm (SKS 1996) Billefjorden Gp; Birger Johnsonfjellet, Sporehogda mbrs; C1, Vis; 4, 17. Murchison Bay Supergroup (Kulling 1934; Flood et al. 1969) Raoldtoppen, Celsiusberget, Franklinsundet gps; Neoptz; 6, 12. t Myalina niveau, bed (Frebold 1930; Buchan et al. 1965) Myalina shale ~ Vardebukta Fm. Mya horizon (Feyling-Hanssen 1995); raised beach deposits, Billefjorden; Late Pleistocene - Early Holocene; 21. t Myalina shale (Lundgren 1887)~lower Vardebukta Fm; Trl; 4, 18. ~t Myklegardfjellet Bed (Birkenmajer 1980) Wimanfjellet Mbr; K1, Ber-Vlg; 4, 19. t Myophoria sst (Anderson 1990)~ Skuld Fm (Bjornoya). Nannbreen Mbr (Birkenmajer 1993) Tonedalen Fm; V, Varl; 10, 13. t Nathorstites Niveau (Stolley 1911) ~ upper Tschermakfjellet Fm; Tr2_3; 4, 18. t Negerfjellet Fm (Lock et al. 1978) Kapp Toscana Gp (in Barentsoya & Edgeoya); Tr2_3, Nor-?Rht; 5, 18. Neukpiggen Fm (Harland et al. 1979) Ferrier Gp; V, Var2; 9,13. Nielsenfjellet Fm (Challinor 1967 from Orvin 1934) Kongsvegen Gp; = units 1-9, Orvins Quartzite & Mica Schist Series; preVend; 9, 13. Nigerbreen Fm (Major & Winsnes 1955) Sofiekammen Gp; O1; 10, 14. t Nissenfjella Fm (Gee & Hjelle 1966) Krossfjorden Gp; Ptz; 8, 12. t Nordaustpynten Mbr (Smith et al. 1976) ~ middle of Dun6rfjellet Mbr of Kongsoya Fm. t Nordbukta Gp (Bjornerud 1990) Dordalen, Thiisdalen, Trinutane, Seljehaugfjellet, Botnedalen, Peder Kokkfjellet, Evafjellet, Kapp Berg fms; Ptz; 10, 12. Nordenski6ldbreen Fm (Cutbill & Challinor 1965) Gipsdalen Gp; Tyrrellfjellet, Cadellfjellet, Minkinfjellet mbrs~Wordiekammen+ Minkinfjellet fms; C2-P~, Mos-Sak; 4, 17. t Nordenski6ldfjellet Schichten (Vonderbank 1970) ~ Aspelintoppen Fm; Pg; 4, 20. * NordhamnaMbr (SKS 1996) Nordkapp Fm; Ci: Tou-Vis; 11, 17. *t Nordkapp Fm (Cutbill & Challinor 1965) Billefjorden Gp; C1, Tou-Vis; 11, 17. :~ Nordmela Fm (Worsley et al. 1988) Realgrunnen Gp; Hammerfest Basin; J1, Het-Sin. t Nordporten Mbr (Fortey & Bruton 1973) Kirtonryggen Fm; O1, Can3; 7, 14. Nordstebreen Mbr (Birkenmajer 1978) Nordstetinden Fm; E-O; 10, 14.

471

t Nordstetinden Fm (Birkenmajer 1958) Sofiekammen Gp; Nordstebreen, Hansbreen mbrs; E-O; 10, 14. t Nordvika Fm (Krasilshchikov 1965)= Norvik Fm Norgekollen fm (this work) the upper fm defining the Kapp Hansteen Gp and comprising mainly quartz-porphyries; Early Neoptz; 6, 12. t Northern Grampian Series (Tyrrell 1924) ,-~Grampian Gp etc; ?O-S; 9, 14. t Norvik Fm (Kulling 1934) Celsiusberget Gp; Neoptz; 6, 12. [Nordvika] t Nottinghambukta Fm (Birkenmajer 1993) Vimsodden Subgp; Kvisla, Pyttholmen, Kvislodden mbrs; Ptz; 10, 12. t Ny-Alesund f m (Livshits 1973)~Broggerbreen Fm in NyAlesund Subgp. *t Ny-Alesund Sbgp (Challinor 1967) Van Mijenfjorden Gp; Broggerbreen, Kongsfjorden fms, Pg, Pal, 9, 20. :~ Nygrunnen Gp (Worsley et al. 1988) Kveite and Kviting fms; Hammerfest Basin; K2; 19. (the only Late Cretaceous strata in the Barents shelf). * Odellfjellet Mbr (Johannessen & Steel 1992) Ebbadalen Fm; Ca, Bsh; 11, 17. t Oil Shale mbr (Falcon 1928; Lock et al. 1978)~upper Barentsoya Fm (cf. Botneheia Fm)= Blanknuten Mbr. t Oil Shale Series (Falcon 1928) ~ upper Barentsoya Fm; Tr2; 4, 18. t Old Red Sandstone (Harland et al. 1974)~ Liefde Bay Supergroup. t Older Dolomite Series (Holtedahl 1920) = Russehamna Fm; V+; 11, 12, 13. t Olenellusbreen Mbr (Birkenmajer 1978) Vardepiggen Fm; El; 10, 14. t Olenidsletta Mbr (Fortey & Bruton 1973); Valhallfonna Fro; O1-Arg; 7, 14. Omondryggen f m (Manby 1986) ~ Roysha Fm t Oozy mound beds (Gregory 1921) ~ upper part of Botneheia Fm. ~t Oppdalen Mbr (Dypvik et al. 1991) Agardhfjellet Fm; Dronbreen, Marhogda + Brentskardhaugen beds; J2, Bth; 4, 19. :~ Oppdals~ta Mbr (Dypvik et al. 1991) Agardhfjellet Fm; J3, OxfKim; 4, 19. Ormen Mbr (Harland, Hambrey & Waddams 1993) Wilsonbreen Fm (WI); Vend., Var2; 7, 13. t Orsabreen Mbr (Friend et al. 1966) Wood Bay Fm; D1, PraEms; 8, 16. *t Orustdalen Fm (Cutbill & Challinor 1965) Billefjorden Gp; Ca, Tou-Vis; 9, 17. t Oslobreen Gp (Harland & Wilson 1956); Hinlopenstretet Spgp; Valhallfonna, Kirtonryggen, Tokammane fms; CO; 7, 14. Otelie Seam (Orvin 1934) Broggerbreen Fm, Tvillingvatnet Mbr; Pg, Pal; 9, 20. t Oxfordbreen Fm (Harland & Wilson 1956; Harland et al. 1966) Veteranen Gp; Fulmarberget, Enpiggen mbrs; Neoptz; 7, 12. t Paierlbreen Mbr (Birkenmajer 1978) Wiederfjellet Fm; O1; 10, 14. * Palanderbukta Mbr (Lauritzen 1981) Kapp Starostin Fro; P2, Gua; 5, 17. t Passage beds (Wordie 1919; Gee et al. 1962) Minkinfjellet Fm. Western part of Ebbadalen Fm; C2, Bsh-Mos; 4, 17. t Passage unit (Klubov 1965)~ Purple shale group ,-~upper part of Edgeoya Fm ~ Tschermakfjellet Fm. Passet Mbr (Smith et al. 1976) Kongsoya Fm (in Kongsoya); JJ-2; 5, 19. ~t Passhatten Mbr (Birkenmajer 1977; Mork et al.) Botneheia Fm (in S); Tr2; 4, 18. t Peaehflya Gp (Harland et al. 1979) Knivodden, Hornnes, Alasdairhornet, Fisherlaguna fms; V; 9, 13. Peder Kokkfjellet Fm (Bjornerud 1990) Nordbukta Gp; Ptz; pre-V; 10, 12. Perleporten Fm (Smith & Armstrong 1996) Ymerdalen Gp; (=Younger Dolomite Series of Holtedahl 1920); O; 11, 14. t Persberget Fm (Flood et al. 1969) Franklinsundet Gp; Neoptz; 6, 12. t Peterbnkta Fm (Harland et al. 1979) Ferrier Gp; V, Var2; 9, 13. o

472

STRATIGRAPHIC GLOSSARY

*t Petrellskaret Fm (Dineley in Gobbett 1963) Charlesbreen Sbgp; C1, Bsh; 9, 17. Petrovbreen Mbr (Harland, Hambrey & Waddams 1993) Elbobreen Fm (E2); Vend, Varl; 7, 13. Pillow Beds (Krasil'shchikov 1973)=Bolster Beds~lower 1st mbr of Svanbergfjellet Fm; Neoptz; 7, 12. t Pinkie complex (Atkinson 1960; Harland et al. 1979) ?Vend., ?Varl; 9, 13. t Pisolitic mbr (Harland 1978) upper of three divs of Fannytoppen Fm. t Pitnerodden Fm (Pchelina 1983)~ Sticky Keep Fm. ~f Pityophyllum layers (Hoel & Orvin 1937)~ lower Helvetiafjellet Fm in Festningen section. t Planetfjella Gp (Harland & Wilson 1956) Stubendorffbreen Spgp; Vildadalen, Fl~ten fins; Neoptz; 7, 12. Plant Ravine Conglomerate ~ Planteryggen Mbr. Planteklofta Mbr (Friend 1961) Mimer Valley Fm, D3, Frs; 8, 16. t Planteryggen mbr (Friend 1961) Mimer Valley Fm; D3, Frs; 8, 16. [SKS to reject]. t Plateau Flags (Gregory 1921)~De Geerdalen Fm; Tr3; 4, 18. J;t Polakkfjellet Bed (Birkenmajer 1975) Wimanfjellet Mbr; J3-K~ Tth-Ber; 4, 19. t Polarisbreen Gp (Harland & Wilson 1956) Hinlopenstretet Spgp; Dracoisen, Wilsonbreen, Elbobreen fms; Vend; 7, 13. t Polhem Fm (Harland et al. 1966) Bleikfjellet Subgp; [~Rittervatnet]; Paleoptz; 7, 12. Polyzoa Lst. (Cutbill & Challinor 1965)~ upper part of Kapp Starostin Fm in Nordaustlandet ~ Hovtinden Mbr. t Posidonomya Layers (Nathorst 1910)~lower Sticky Keep Fro; Trl; 4, 18. Posidonomya Limestone (Mojisisovics 1886)~ Posidonia Layers Sticky Keep Fm. t Princesse Alice Fm (Murashov & Mokin 1976). Princesse Alicefjellet Mbr (Murashov & Mokin 1976, Friend et al. 1997) Rivieratoppen Fm; D1, Lok; 8, 16. t Productus-bearing limestones and cherts (Nordenski61d 1871) Kapp Starostin Fm; P1 2, Art-Gua; 4, 17. t Profilbekken Mbr (Fortey & Bruton 1973); Valhallfonna Fm; O1-2, Arg-Lln; 7, 14. Pseudomonotis shale (Lundgren 1887)~ upper Vardebukta Fm; Trl; 4, 18. t Pteraspistoppen Mbr (Harland 1985 from Gee) Lerneroyane Fm; Ptz; 8, 12. t Ptychites beds (Spath 1921)~in Botneheia Fm (Frechites laqueatum zone) Purple (blue and purple) shale group (Falcon 1928) above oil shale group ~ Tschermakfjellet Fm. t Pyefjellet beds (Pickard et al. 1995) Cadellfjellet Mbr; C2, Mos; 4, 17. Pyramiden (conglomerate) beds (Gee et al. 1952)~Pyramiden Fm (Lyutkevich 1936)~ Odellfjellet Mbr; Ca, Bsh; 4, 17. Pyttholmen Fm (Czerny et al. 1993) their Eimfjellet Gp; Ptz; 10, 12. Pyttholmen Mbr (Birkenmajer 1992, 1993) Nottinghambukta Fm; Ptz; 10, 12. = Pyttholmen Fm. Quartz Mica Schist Series (Orvin 1934) = Neilsen Fm; pre-Vend; 9, 13. Quartzite shale fro, Oscar lI Land t Rabotdalen Mbr (Murashov & Mokin 1976) Rivieratoppen Fm; D1, Lok; 8, 16. Rabotpasset Fm (Friend et al. 1997) Siktefjellet Gp; S4?D1, Pri-Lok; 8, 16. Raddedalen mbr (this work); Kapp Starostin Fm (in mid Edgeoya) Ragnhild seam (Orvin 1934) Broggerbreen Fm, Tvillingvatnet Mbr; Pg, Pal; 9, 20. Rasstupet Mhr (Major & Winsnes 1955) Hornsundtind Fm; O1, Can3; 10, 14. Raudfjorden cgl f m ~ Rivieratoppen Fm. Raudfjorden Series (Murashov & Mokin 1976)~Red Bay Group.

t Raudstup-Sal6dd Fm (Kulling 1934) Celsiusberget Gp; Neoptz; 6, 12. [Raudstupet-Sal6dden]. Realgrunnen Gp (Worsley et al. 1988) Ste, Nordmela, TubAen and Fruholmen fms; Hammerfest Basin; Tr3-J2, Nor-Baj; 18, 19. (Mork et al. SKS) suggested it to replace upper Kapp Toscana Gp = 'Wilhelmoya Subgp' = Wilhelmoya Fm + Brentskardhaugen Bed in this work. Red Bay conglomerates (Holtedahl 1914; Friend 1961) ~ Rivieratoppen Fm. t Red Bay Gp (Holtedahl 1914; Friend et al. 1966); Liefde Bay Spgp; Ben Nevis, Fr~enkelryggen, Andr~ebreen, Rivieratoppen fms; D1, Lok-Pra; 8, 16. t Red Bay Series (Holtedahl 1914) ~ Red Bay + Siktefjellet Gps. Red conglomerate (Andersson 1900) Landnordingsvika Fm; P2, Bsh; 11, 17. *t Reinhardpynten Fm (Livshits 1967) McVitiepynten Sbgp; Pg; 9, 20. t Reinodden Fm (Orvin 1940)~ Hyrnefjellet Fm; C2-P1; 10, 17. Reke Mbr (Mork et al. SKS) middle mbr of Fruholmen Fro, Hammerfest Basin; Tr3, Nor. t Renardbreen Division (Harland 1978) e. equiv, of Dundrabeisen Fm in W; V, Var2; 10, 13. t Renardodden Fm (Livshits 1973; Thiedig et al. 1979) Calypsostranda Gp; Pg; 10, 20. t Retzia Limestone (Lundgren 1887) ~ upper Vardebukta Fm; Trl; 4,18. t Retziusfjellet Mbr (Smith et al. 1976) Kongsoya Fm (in Kongsoya); J~3, ?Bth-Kim; 5, 19. t Reuterskidldfjellet ssts (Friend 1961, 1966) part of Austfjorden (sst) Mbr. t Revdalen Fm (Birkenmajer 1958, 1992) Isbjornhamna Gp; Ptz; 10, 12. * Revtanna mbr (SKS 1996) Kapp Starostin Fm; P2, Gua; 10, 17. t Rheanuten Beds (Harland et al. 1966) Cavendishryggen Mbr; Neoptz; 7, 12. t Richarddalen Complex (Hjelle & Lauritzen 1982 after Gee), Ptz; 8, 12. *t Rifleodden (conglomerate) bed (Gjelberg 1981) Tunheim Mbr; D3, Fam; 11, 17. Rijpfjorden Granite (Flood et al. 1969) ?Ptz; 6, 12. t Rittervatnet Fm (Harland et al. 1966) Bleikfjellet Subgp; 3 mbrs: U amph, feldspth, pel + psam + metatilloid; M psam pel; L marble, qi & metatilloid, Paleoptz; 7, 12. Rivieratoppen Fm (Friend et al. 1997) Red Bay Gp; S4-D1, Pri-Lok, 8, 16. t Roaldtoppen Gp (Flood et al. 1969) Murchison Bay Spgp; Rysso, Hunnberg fms; Neoptz; 6, 12. Rochesterpynten Fm (Harland et al. 1993, p. 100) Calypsostranda Gp, below Skilvika Fm; Pg; 10, 20. *t Roedvika Fm (Cutbill & Challinor 1965) Billefjorden Gp; Tunheim, Kapp Levin, Vesalstranda mbrs; D3, Fam, 11, 17. t Ros~nfjella Mbr (Wallis 1969) Vildadalen Fm; Neoptz; 7, 12. t Rossbukta Fm (Harland et al. 1979) Geikie Gp; V, Var2; 9, 13. t Roysha Fm (Harland et al. 1979) Scotia Gp; V, ?Edi; 9, 13. [Royshaugen]. t Royshaugen Fm (Krasil'shchikov in Abakumov et al. 1990)~ Roysha Fm ~t Rurikfjellet Fm (Parker 1967) Janusfjellet Subgp; Ullaberget & Wimanfjellet mbrs; K1 ?Tth-Brm; 4, 19. t Rurikfjellet horizon (Pchelina 1983) ~ strata coeval with Rurikfjellet Fm. t Rurikfjellet mbr (Birkenmajer 1975)~ lower part of Rurikfjellet Fm. t Russehamna Fm (Krasil'shchikov & Livshits 1974) Bjornoya Gp; (=Older Dolomite Series o f Holtedahl 1920) V-Pre-V; 11, 13. t Russepasset Mbr (Birkenmajer 1978) Bfftstertoppen Fm; ?El; 10, 14. t Ryss6 Fm (Nordenski61d 1863; Kulling 1934; Lauritzen & Ohta 1984) Roaldtoppen Gp; now excludes Backaberget Fro; Neoptz; 6, 12.

STRATIGRAPHIC GLOSSARY Sdlodd Fm (Kulling 1934)~ Raudstup-S~ilodd Fm. [S~ilodden] * Sandhamna beds (SKS 1996) Tokrossoya Fm; P2; 10, 17. t Sandsteinreihe (Nathorst 1910) ~ Shore sst in Festningen section ,-~Helvetiafjellet Fm. t Sandstone group (Falcon 1928) above purple shales gp in Edgeoya+Barentsoya~Negerfjellet Fm of Lock et al. 1878) (~De Geerdalen Fro). t Sarkofagen Fm (Major & Nagy 1964)~Grumantbyen F m § Hollendardalen Fm; Pg; 4, 20. t Sars Fm (Atkinson 1963)~ Balanuspynten Fm; Pg; 9, 20. *t Sarsbukta mbr (SKS 1995) Balanuspynten Fm; Pg; 9, 20. t Sarsoyra Fm (Harland et al. 1979) crops out between Aavatsmarkbreen and Balanuspynten fms; ?Pz; 9, 14, 12. * Sarstangen mbr (SKS 1995 after Larsen) Balanuspynten Fm; Pg; 9, 20. ~:t Sassendalen Gp (Buchan et al. 1965) Botneheia, Sticky Keep, Vardebukta, Barentsoya, Kistefjellet fms; Trl_2; 4, 18. t Saxicava horizon (9.) raised beach deposit; Q. *t Scheteligfjellet Fm (Gobbett 1964; Cutbill & Challinor 1965) Charlesbreen Sbgp; C2, Mos; 9, 17. J;t Schiinroekfjenet Mbr (Nagy 1970) Carolinefjellet Fm; K1, Alb; 4, 19. t Scotia Gp (Tyrrell 1924; Harland et al. 1979) Roysha, Kaggen, Baklia fms; V, Edi; 9, 13. t Sederholmfjellet Mbr (Harland et al. 1966) Eskolabreen Fm; Paleoptz; 7, 12. * Seidfjellet Suite (SKS 1995) plateau basalts, replaces Sorlifjellet Fm in this work. t Selander Fm (Burov et al. 1965) ,-~Selanderneset Mbr; P2; 5, 17. * Selanderneset Mbr (Burov et al. 1965) Kapp Starostin Fm; P2, Gua; 5, 17. Seljehaugfjellet Fm (Bjornerud 1990) Nordbukta Gp; 2mbrs unnamed; Ptz; pre-V; 10, 12. ~t Selmaneset Mbr (Buchan et al. 1965) Vardebukta Fm; Trl; 4, 18. *t Selvhgen Fm (Atkinson 1963) Buchananisen Subgp; Pg; 9, 20. * Sergeijevfjellet Fm (Siedlecki 1960) Billefjorden Gp; C1, Vis; 10, 17. * Sesshogda Fm (Livshits 1967) McVitiepynten Subgp; Pg; 9, 20. t Shale-alternating-greenish grey sst fm (Kotlukov 1936)~ Hollendardalen Mbr. t Shaly green sst fm (Lyutkevich 1937)~ Hollendardalen Mbr. Shore Sandstone (Hagerman 1925)~Helvetiafjellet Fm; K1; 4, 19. t Sigfredbogen Fm (Harland 1978) for outcrop west of Kviveodden identified by Birkenmajer (1958), with Slyngfjellet and Deilegga (Bergskardet) fms south of Hornsund, name introduced because that correlation was doubted. Ptz; 10, 12. t Signehamna Fm (Gee & Hjelle 1966) Krossfjorden Gp; Ptz; 8, 12. Sigurdfjellet Division (Goujet 1984) Wood Bay Fm; D~, LokPra; 8, 16. Siksaken Mbr (Buchan et al. 1965) Vardebukta Fm; Trl, ?Nml; 4,18. t Siktefjellet Gp (Gee & Moody Stuart 1966); Liefde Bay Spgp; Albertbreen, Lilljeborgfjellet, Rabotpasset fms; ?S4-?Db ?Pri?Lok; 8, 16. t Siktefjellet Sandstone Fm (Gee & Moody Stuart 1966)~ Albertbreen Fm +part Andrrebreen Fm; ?$4, Pri?; 8, 16. t Singerfjelletfm (Pchelina 1983) lower part of Innkjegla Mbr of Carolinefjellet Fm. t Sjdanovfjellet Mbr (Major & Winsnes 1955) Hornsundtind Fm; O1, Can3; 10, 14. :~ Sjogrenfjellet Mbr (Smith et al. 1976) Wilhelmoya Fm in Kongsoya; Tr2-J1; ?Rht-Sin; 5, 18, 19. t Skhlfjellet Fm (Birkenmajer 1958; Czerny et al. 1993) Subgp (Birkenmajer 1975, 1993) Eimfjellet Gp; Torbjornsenfjellet, Gangpasset, Angellfjellet, Brattegga mbrs; Ptz; 10, 12. t Skamdalen mbr (Murashov & Mokin 1976) Grey Hoek Fm; D2, Eif; 8, 16. (SKS may reject). ~t Skilisen bed (Birkenmajer 1977, refined by Mork et al. 1982) Retzia 1st ~ in upper Vardebukta Fm (?Siksaken Mbr)

t

473

Skilisen Retzia Lst (Worsley & Mork 1978)~ Sticky Keep Fm. *t Skilvika Fm (Livshits 1973; Thiedig et al. 1979) Calypsostranda Gp; Pg; 10, 20. t Skioldkollen Mbr (Friend et al. 1966) Wood Bay Fm; D1, Pra-Ems; 8, 16. Skjerstranda Fm (Czerny et al. 1993) Eimfjellet Gp; Ptz; 10, 12. Skoddebukta Mbr (Birkenmajer 1992, 1993) Elveflya fm; V, Varl; 10, 13. t Skoddefjellet Fm (Birkenmajer 1958, 1992) Isbjornhamna Gp; Ptz; 10, 12. f S k r e k k subformation (Pavlov et al. 1983) biostrat zone in Veselstranda Mbr; D3, Fam; 11, 17. ~t Skuld Fm (Krasil'shchikov & Livshits 1974) Kapp Toscana Gp, in Bjornoya; Tr2_3, Lad-Crn; 11, 18. Slatto mbr (?)~ upper Nielsenfjellet Fm. t Slakli Series (Major & Winsnes 1955) See Slaklidalen Fm. t Slaklidalen Fm (Major & Winsnes 1955; Birkenmajer 1960) Sofiekammen Gp; El; 10, 14. Slangen Mbr (Harland, Hambrey & Waddams 1993) Elbobreen fm (E4); Vend. Varl; 7, 13. t Slate Quartzite Series (Holtedahl 1920)=Sorhamna Fm; V; 11, 13. t Slatto (fjellet) mbr (Barbaroux 1966) upper part of Nielsenfjellet Fm Slettfjelldalen Fm (Craddock et al. 1985; Harland et al. 1993) Konglomeratfjellet Gp; (W. equiv of Solhogda Fm) V, Varl; 10, 1. Slottet Bed (Pchelina, Mork et al. SKS) cgl at base of Wilhelmoya Fm in Spitsbergen; Tr3, Nor. :~ Slottsmoya Mbr (Dypvik et al. 1991) Agardhfjellet Fm; J3, KimTth; 4, 19. t Slyngfjellet Fm (Birkenmajer 1958, restricted Harland 1978) Sofiebogen Gp; U & L mbrs; V, Var; 10, 13. ~t Smalegga Mbr (Mork et al. 1982) Wilhelmoya Fm; Tr3, Rht; 4, 18. t Smeerenburgfjorden Cpx (Abakumov 1976) Stratigraphic elements not distinguished because Cpx is largely (?Caledonian) migmatic transformation of lower parts of Krossfjorden Group. t Smntsbreen Fm (Harland & Wilson 1956) Finnlandveggen Gp; Westbyfjellet + Bohryggen mbrs; Paleoptz; 7, 12. t Smutsdalen Fm (Abakumov 1965: upper part of Austfjorden series) ~ part of Harkerbreen Gp with quartzites and amphibolites. t Snofjella marbles and schists (Preston 1969)~ Southern development of Lernereyane Fm. :~ Snadd Fm (Worsley et al. 1988) only unit of Storfjorden Gp in Hammerfest Basin. t Sofiebogen Group (Birkenmajer 1958, 1993) G~shamna, Hrferpynten, Slyngfjellet fms. The stratigraphic grouping is in doubt; Ptz; 10, 12, 13. t Sofiekammen Gp (Birkenmajer 1958, 1975) Hornsund Spgp; Nordstinden, Gn~lberget, Slaklidalen, Vardepiggen, Bl~stertoppen fms; El; 10, 14. t Soft black shale f m (Kotlukov 1936)~ Frysjaoddden Fm. t Solhogda Fm (Harland 1978; Harland et al. 1993) Konglomeratfjellet Gp; (E equiv, of Solhegda Fm) V, Varl; 10, 13. ~t Somovbreen Mbr (Birkenmajer 1977; Mork et al. 1982) Botneheia Fm (in S); Tr2; 4, 18. Sofie Seam (Orvin 1934) Kongsfjorden Fm, Kolhaugen Mbr; Pg, Pal; 9, 20. t Sorbreen Fm (Harland et al. 1966) Tordenryggen Subgp; Paleoptz; 7, 12. * Sorfonna Mbr (SKS 1996) Gipshuken Fm; P1, Art; 5, 17. t Sorhamna Fm (Krasil'shchikov & Livshits 1974) Bjornoya Gp: (--Slate Quartzite Series of Holtedahl 1920); ?V; 11, 13. t Sorkapp Fm (Pchelina 1980)~Tumlingodden horizon in Wilhelmoya Fm. t Sorkapp Land Gp (Birkenmajer 1958, 1975) Hornsund Spgp; Arkfjellet, Hornsundtind, Nigerbreen, Dusken, Luciapynten, Wiederfjellet fms; O1-2; 10, 14. Sorlifjellet (lava) f m (this work) to include 9 outliers on mountain tops; Ng; Mio; 8, 21. but should be replaced by Seidfjellet (lava) fm (SKS 1995), has been replaced.

t

474 t t t t

t *

t t

t t t St

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1:

t t t

t

*t t

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t

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t St

STRATIGRAPHIC GLOSSARY

Sparreneset Fm (this work); = the upper three mbrs of Kulling's (1934) Cape Sparre Fm; EO; 6, 14. Plateau lavas in N. Spitsbergen; Ng, Mio; 8, 21. see Seidfjellet Suite = Sorliefjellet (lava) fro. Spirifer limestone (Andersson 1900) Miseryfjellet Fm; P1-2; Kun-Ufi; 11, 17. Spirifer limestone (Nordenski61d 1871) Voringen Mbr; P1, ArtKun; 4, 17. Spora Mbr (Fortey & Bruton 1973) Kirtonryggen Fm; O1, Can1; 7, 14. Sporehogda Mhr (Cutbill & Challinor 1965) Mumien Fm; C1, Vis; 4, 17. St Jonsfjorden Gp (Harland et al. 1979); Alkhorn; Lovliebreen, Moefjellet, Trondheimfjellet fms; V1, Varl; 9, 13. Starostin Fm (Burov et al. 1965)~Kapp Starostin Fm; P12; 4, 17. Steen group (Barbaroux 1966)~ Steenfjellet Fm. Steenfjellet Fm (Orvin 1934) Kongsvegen Gp; pre-Vend; 9, 13. Steinkobbe Fm (Mork et al. SKS) ~ Kobbe Fm of Hammerfest Basin but in Svalis Dome. Steinsvikskardet Fm (Birkenmajer 1958; Czerny et al. 1993) Eimfjellet Gp; Ptz; 10, 12. StensiiJfjellet Mbr (SKS 1996) Kapp Starostin Fm; P2, Gua; 4, 17. Sticky Keep Fm (Buchan et al. 1965) Sassendalen Gp; Kaosfjellet & Iskletten mbrs; Trl, Nml-Spa; 4, 18. Stjordalen Division (Foyn & Heintz 1943; Friend 1961) Wood Bay Fm; D~; ?Pra-Ems; 8, 16. Sto Fm (Worsley et al. 1988) Realgrunnen Gp; Hammerfest Basin; J1 2, Plb-Bth. Storbreen Subgp (Birkenmajer 1977)~Sassendalen Gp in S. Spits.1 2; Trl 2; 4, 18. Storfjorden Gp (Worsley et al. 1988) = Snadd Fm in Hammerfest Basin; correlates with De Geerdalen, Tschermakfjellet and Skuld fms; has been suggested (Mork et al. SKS) to replace lower Kapp Toscana Gp; Tr3, Car, Nor; 18. Stormerfjellet schists (Harland & Wilson 1956)~ Smutsbreen Fm Storvika f m (Cambridge Group)~ Evafjellet Fm. Storvola Fm (Livshits 1967) ~Aspelintoppen Fro; Pg; 4, 20. Stubendorffbreen Spgp (Harland et al. 1966)= Lower Hecla Hoek of Harland & Wilson 1956; Planetfjella, Harkerbreen, Finnlandveggen gps; Ptz, 7, 12. Sfisswassenschichten mit Lioplax (Hoel & Orvin 1937)~in Helvetiafjellet Fro. Sutorfjella (conglomerate) mbr (Harland et al. 1979) Barents Fro; ?S; 9, 14. Svanbergf)/ellet dolomites (Wilson 1961). Svanbergfjellet Fm (Harland & Wilson 1956) Akademikerbreen Gp; 4mbrs: U. Lst; Stromatolitic Dst; Lst; (L) Dst; Neoptz; 7, 12. Svanberg[jellet lower 1st division (Wilson 1961). Svarteper (coal) Seam (?); Firkanten Fm in E. Nordenski61d Land; Pg, Pal; Svartknausane Fm (Major & Nagy 1972)~Sassendalen Gp in Nordaustlandet; Trl 2; 5, 18. Svartrabbana Fm (Gee & Teben'kov 1996) Kapp Hansteen Gp in central Nordaustlandet. Early Neoptz; 6, 12. Svea (coal) seam (?); Firkanten Fm in E Nordenski61d Land; Pg, Pal. Sveanor Fm (Kulling 1934, Krasilsh'chikov 1967) Gotia Gp; was modified by Krasil'shchikov to comprise only the tilloid and to exclude tb,e Backaberget Fm; V, Var2; 6, 13. Svenbreen Fm (Cutbill & Challinor 1965) an earlier composite unit, upper part is Hultberget Fm and lower part is Mumien Fm; C1, Vis; 4, 17. Svenskebukta mbr (?) Kongsoya Fm. Svenskeega Mbr (Cutbill & Challinor 1965) Kapp Starostin Fro; P1 2, Kun-Gua; 9, 17. Svenskoya Fm (Smith et al. 1976)~Wilhelmoya Fm in Kong Karls Land.

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*t t t

Sylodden Fm (Pchelina 1983) ~ Rurikfjellet Fm N of Isfjorden Tfihreen Mbr (Wallis 1969) Vildadalen Fm; Neoptz; 7, 12. Tage Nilsson Fm (Murashov & Mokin 1976)~Wijde Bay Fm. Tfirnkanten Fm (Dineley 1958) Charlesbreen Sbgp; Jotulslottet Mbr; C2, Mos; 9, 17. Tavlefjellet mbr (Murashov & Mokin 1976) Grey Hock Fm; D2, Eif; 8, 16. ( S K S to reject), confused with older name for Neogene plateau lavas. Taxodium (shale) bed (Heer 1870) bed within Todalen Mbr; Pg, Pal., 4; 20. Teistberget Fm (Pchelina 1980)~Tumlingodden horizon in Wilhelmoya Fm. Teltfjellet Mbr (Holliday & Cutbill 1972)~ Trikolorfjellet Mbr; C2, Bsh; 4, 17. Tempelfjorden Gp (Cutbill & Challinor 1965) B~insow Land Spgp; Kapp Starostin, Tokrossoya, Miseryfjt fms; P1-2, ArtKaz; 4, 5, 9, 10, 11, 17. Templet Mbr (SKS 1996) Gipshuken Fm; P1, Art; 4, 17. Terrace cpx (Fehling-Hanssen 1955) Quaternary terranes up to 60 m a.s.1, in Billefjorden area. Terrierfjellet Mbr (SKS 1996; Lonoy et al. 1995) Minkinfjellet Fm; Urmstonfjellet bed; C2, Mos; 4, 17. Tetradium Limestone (Holtedahl 1920)=Antarcticfjellet Fm; O; 11, 14. Thiisdalen Fm (Bjornerud 1990) Nordbukta Gp; Ptz; pre-V; 10, 12. Thiisfjellet Fm (Craddock et al. 1985; Harland et al. 1993) Konglomeratfjellet Gp; V, Varl, 10, 13. Tillitic conglomerate (Hjelle et al. 1979)~ Haaken Fm + Trondheimfjella fms Tilloid unit (Harland 1978),-~Fannypynten Fm Tirolerpasset Series (Rozicki 1959)~Janusfjellet Subgp; JK; 4, 19. (Mork et al. SKS retain name as mbr for ill defined middle part of Janusfjellet Subgroup). Todalen Mbr (Steel et al. 1981) Firkanten Fro; Pg, Pal; 4, 20. Todalen (coal) seam (Major & Nagy 1972). Tokammane Fm (Harland et al. 1966) Oslobreen Gp; Ditlovtoppen, Topiggane, Blfirevbreen mbrs; El; 7, 14. Tokrossoya Fm (Siedlecki 1964) Tempelfjorden Gp; Sandhamna beds; PI-2: Art-Gua.; 10, 17. Tonedalen Fm (Birkenmajer 1975) L Deilegga Gp; Iskantelva, Nannbreen, Lippertoppen mbrs; V; 10, 13. Topiggane Mbr (Swett 1981) Tokammane Fm; El; 7, 14. Torbjornsenfjellet Mbr (Birkenmajer & Narebski 1960, Birkenmajer 1992) Skfilfjellet Fro; Ptz; 10, 12. Tordenryggen Sbgp (Harland & Wilson 1956; Harland et al. 1992) Harkerbreen Gp; Sorbreen + ?Polhem fms; Paleoptz; 7, 12. Tordenskiiiidberget Mbr (Smith et al. 1976) Kongsoya Fm (in Kongsoya); Ki, Vlg-Hau; 5, 19. Torell Land Gp (Birkenmajer 1977) ~ Sassendalen + Kapp Toscana gps; Tr in S. Spits., 4, 18. Torellbreen Supergp (Birkenmajer 1975) Deilegga, Eimfjellet & Isbjornhamna gps ~ Precambrian of SW Wedel Jarlsberg Land. Torellnesfjeilet fm (?) upper Kapp Toscana Gp in Nordaustlandet; Tr3. Transitional Mbr (Worsley 1973) Wilhelmoya Fm, third up of four mbrs. Treskelen Sbgp (SKS 1996) Gipsdalen Gp; Treskelodden; Hyrnefjellet fms; C2-Pj, Bsh-Ass; 10, 17. Treskelodden Fm (Birkenmajer 1959) Treskelen Sbgp; C2-P1, Gze-Ass; 10, 17. Trikolorfjellet Mbr (Holliday & Cutbill 1972) Ebbadalen Fm; C2, Bsh; 4, 17. Trinutane Fm (Bjornerud 1990) Nordbukta Gp; three mbrs unnamed; Ptz; pre-V; 10, 12. Triungen Mbr (Cutbill & Challinor 1965) Horbyebreen Fm; D3-C1, Fam-Tou; 4, 17. Trondheimfjella Fm (Wilson in Harland 1960; Harland et al. 1979) St Jonsfjorden Gp; [the Lower tillite] V1, Varl; 9, 13. Trygghamna Fm (Dineley 1958)~ Orustdalen Fm; Cl, Tou-Vis; 9, 17.

STRATIGRAPHIC GLOSSARY {t Tsehermakfjellet Fm (Buchan et al. 1965) Kapp Toscana Gp; Tr2 3; Lad-Crn; 5, 18. t Tub~ten Fm (Worsley et al. 1988) Realgrunnen Gp; Hammerfest Basin; Jb Het-Sin. {t Tsjebysjovqellet Mbr (Major & Winsnes 1955) Hornsundtind Fm; O~, Can3; 10, 14. $t Tumlingodden f m (Pchelina 1980) part of Tumlingodden horizon ~ Wilhelmoya Fm. t Tumlingodden horizon (Pchelina 1980) all Svalbard strata coeval with Wilhelmoya Fm + Brentskardhaugen Bed of Agardhfjellet Fm. ]- Tumlingodden Mbr (Worsley 1973) Wilhelmoya Fm; Tr3-J1, Rht-?Het; 5, 18. t Tunheim Mbr (Horn & Orvin 1923; Cutbill & Challinor 1965) Roedvika Fm; Rifleodden bed; D3-C~, Fam-Tou; 11, 17. *t Tunheim Mbr (Worsley & Edwards 1976) upper of three mbrs of Roedvika Fm in Bjornoya. t Tunheim series (Horn & Orvin 1928) Coal-bearing part of Tunheim Member. t Tunheim subformation (Pavlov et al. 1983) after Tunheim Series (Horn & Orvin 1928) is lower coalbearing part of Tunheim Mbr; D3, Fam; 11, 17. {t Tvillingodden Fm (Mork et al. 1982)=Sticky Keep Fm in W Spits.; Trl; 4, 18. t Tvillingodden Fm (sensu Pchelina 1980, 1983) Kapp Toscana Gp : Norian age deposits in W. Spitsbergen; also equivalent to Knorringfjellet Mbr. * Tvillingvatnet Mbr (SKS 1995) Kongsfjorden Fm; Pg, Pal; 9, 20. *t Tyrrellfjellet Mbr (Cutbill & Challinor 1965) Wordiekammen Fm; Kiaerfjellet, Finlayfjellet; Brucebyen beds; C2-P1, Gze-Sak; 4, 17. t Uleneset Fm (Smith 1975) ~ upper De Geerdalen Fm in Wilhelmoya; Tr3; 5, 18. {t UUaberget Mbr (Rozicki 1959) Rurikfjellet Fm; Kl, Vlg-Hau; 4, 19. t Unterer Gipsstufe (Nathorst 1910)~ Ebbadalen Fm. t Upper argillite Fm (Livshits 1965)~ Frysjaodden Fm. t Upper black shale series (Nathorst 1910)~ Frysjaodden Fm. t Upper coal-bearing series (Nathorst 1910) ~ Aspelintoppen Fm. t Upper coal-bearing sst f m (Lyukevitch 1937)~Aspelintoppen Fm. Upper division of Marietoppen Fm (Murashov & Mokin 1976) cf. Grey Hoek Fm. t Upper fissile sst f m (Lyukevitch 1937)~ Battfjellet Fro. ~f Upper gypsiferous series (Gee et al. 1952) Gipshuken Fm; P1, Sak-Art; 4, 17. t Upper gypsum zone (Cutbill & Challinor 1965) upper Gipshuken Fm. in W Spits.; P 1, Sak-Art; 4, 17. t Upper lamina sandstone (Hagerman 1925)~ Langstakken Mbr; K1; 4, 19. Upper limestone f m (Orvin 1934)~ Generalfjella Fm. t Upper nodule beds (Gregory 1921)~ Tschermakfjellet Fro. -~ Upper plant-bearing sst series (Orvin 1940) ~ Aspelintoppen Fm. t Upper Posidonia shales (Spath 1921)~ Sticky Keep Fm. Upper saurian niveau (Wiman 1910) ~ Tschermakfjellet Fm; Tr2; 4,18. t Upper sst f m (Hoel 1929, Livshits 1965) ~ Battfjellet + Aspelintoppen fms. t Upper transitionalfm (Livshits 1965)~ lower Battfjellet Fm. t Upper unit (Tyrrell 1924 in Prins Karls Forland)~ McVitiepynten subgp. :~t Urd Fm (Krasilshchikov & Livshits 1974) Sassendalen Gp; Verdande Bed; Tr~ 2; 11, 18. * Urmstonfjellet bed (Holliday & Cutbill 1972) Terrierfjellet Mbr; C2, Mos; 4, 17. ~( Ursa sandstone (Holtedahl 1920) Roedvika+Nordkapp fms; D3-C1, Fam-Vis: 11, 17. ~ Urnetoppen Mbr (Birkenmajer 1977; Worsley & Mork 1978) in Vardebukta Fm in S. t Utnes Fm (Harland et al. 1979) Grampian Gp; ?O-S; 9, 14.

475

t Vaktaren Mbr (Friend et al. 1966) Wood Bay Fm; D1, Pra-Ems; 8, 16. t Valhallfonna Fm (Vallance & Fortey 1968); Oslobreen Gp; Profilbekken, Olenidsletta mbrs; O. Arg-Lln; 7, 14. t Van Keulenfjorden Fm (Pchelina 1980, 1983) Sassendalen Gp = Ladinian deposits in W & S Spits. { Van Keulenfjorden Mbr (Pchelina 1983; Mork et al. SKS for mbr of Bravaisberget = Sticky Keep Fm). *t Van Mijenqorden Gp (Harland 1969) Ny .~lesund Subgp; Aspelintopppen, Battfjellet, Frysjaodden, Grumantbyen, Basilika, Firkanten fins; Pg ; 4, 20. {t Vardebukta Fm (Buchan et al. 1965) Sassendalen Gp; Siksaken & Selmaneset mbrs; Trb Gri-Nml; 4, 18. t Vardebukta horizon (Pchelina 1983) ~ all coeval Vardebukta Fm strata t Vardepiggen Fm (Birkenmajer 1975) Sofiekammen Gp; Flogtoppane, Midifjellet, Olenellusbreen mbrs; C1; 10, 14. t Vdrsolbukta unit (Harland 1978)~ Gravsjoen unit. t Vassfaret Fm (Harland et al. 1966) Bleikfjellet Subgp; 3mbrs: U, M + L; Paleoptz; 7, 12. t VegardFm (Dineley 1958)~Vegardfjella Fm; C1, Vis; 9, 10, 17. * Vegardfjella Fm (Dineley 1958) Billefjorden Gp; C1, Vis; 9, 10, 17. Veidebreen mbr (this work) Kapp Starostin Fm (in SW Edgeoya). * Vengeberget Mbr (SKS 1996) Gipshuken Fm; P1, Sak; 4, 17. t Verdalen Mbr (Foyn & Heintz 1943) Grey Hoek Fm/Wood Bay Fm; 8, 16. ~t Verdande Bed (Krasil'shchikov & Livshits 1974) Urd Fm; uppermost layer of Urd Fm in Bjornoya, Tr2; 11, 18. t Vesalstranda Mbr (Worsley & Edwards 1976) Roedvika Fm; D3, Fam; 11, 17. Vestervdgen division (Harland et al. 1993) at base of eastern sequence of Kapp Lyell Group beneath Renardbreen and approximately equivalent to Logna Formation. t Vestg6tabreen Cpx (Horsfield 1972; Harland et al. 1979; Hjelle et al. 1979); O1 2, 9, 14. l- Veteranen Gp (Harland & Wilson 1956; Harland et al. 1966) Lomfjorden Spgp; Oxfordbreen, Glasgowbreen, Kingbreen, Kortbreen fms; Neoptz; 7, 12. Vikinghogda fill (Mork et al. SKS) to combine redescribed Deltadalen (=Vardebukta) and Sticky Keep mbrs, (fms) in central Spitsbergen; Trl. and specially in Edgeoya and Barentsoya where constituent units are not easily distinguished. t Vildadalen Fm (Wallis 1969) Planetfjella Gp; Ros6nfjella, .Albreen, Alryggen, Tftbreen mbrs; Neoptz; 7, 12. Vimsa Mbr (Birkenmajer 1992, 1993) Elveflya Fm; V, Varl; 10, 13. t Vimsodden Subgp (Birkenmajer 1958, 1993) Jens Erikfjellet, Elveflya, Nottinghambukta fms; Ptz; 10, 13. Vimsodden Subgp (modified here after Czerny et al. 1993 to exclude Nottinghambukta Fm) V; 10, 13. Vonbreen (sst) Fm (Hoel 1914; Foyn & Heintz 1943) local development of upper Red Bay Group E. of Breibogen Fault Zone; D~; 16. *t Varingen Mbr (Cutbill & Challinor 1965) Kapp Starostin Fm; Pa, Art-Kun; 4, 17. ~f Waggonwaybreen (Abakumov 1976)~ lower part of Smeerenburgfjorden Cpx. Werenskiold Gp (Harland et al. 1993) combined Deilegga, Vimsodden, Slyngfjellet, Sk~tlfjellet and Gulliksenfjellet units approximates Werenskioldbreen Group (Krasil'shchikov & Kovokva 1975). To exclude Early Neoproterozoic Eimfjellet Group (sensu Czerny et al. 1993) the name Austre Torrellbreen Group is proposed in this work. ~f Werenskioldbreen Gp (Krasil'shchikov & Kovaleva 1975) combines Skfilfjellet, Vimsodden + Dunderbukta units in this work thought to combine Early NeoProterozoic and Vendian strata, see Werenskiold Group; Ptz; 10, 12. t Westbyfjellet Mbr (Harland et al. 1966) Smutsbreen Fm; Paleoptz; 7, 12. t Westmanbukta Fm (Flood et al. 1969) Franklinsundet Gp; Neoptz; 6, 12.

476 J; Wibebreen

STRATIGRAPHIC GLOSSARY mbr (Birkenmajer 1977) in Sticky Keep Fm,

t

t

t t t

t

t

t

t

*

Wichebukta Fm (Pchelina 1980, 1983)~ Sticky Keep Fm = Olenekian deposits in E Spits. Wiederfjellet Fm (Birkenmajer 1959) Sofiekammen Gp; Go6sbreen, Paierbreen mbrs; O1; 10, 14. Wijde Bay Fm (Holtedahl 1914; Friend et al. 1966); Andrbe Land Gp; D2 ?D3, ?Eif-Giv-?Frs; 8, ?10, 16. Wijdefjorden Series,.~Wijde Bay Fm; 02-3; 8, 16. Wilhelmoya Fm (Worsley 1973) Kapp Toscana Gp; Tumlingodden, Transitional, Bjornbogen, Basal mbrs; Lyngfjellet, Flatsalen, Mohnhogda, Sjogrenfjellet, Kapp Koberg, Smallegga, Nottingfjellet mbrs; Tr ?J, Rht-?Het; 5, 18. Wilhelmoya Subgp (Mork et al. SKS)=Wilhelmoya F m + Brentskardhaugen Bed= Realgrunnen Gp of Worsley et al. 1988. Wilsonbreen Fm (Harland et al. 1966) Polarisbreen Gp; 3mbrs: W3, Gropbreen; W2, M. Carb.; W1, Ormen; Vend., Var2; 7, 13. Wimanfjellet Mbr (Dypvik et al. 1991) Rurikfjellet Fm; Polakkfjellet & Myklegardfjellet beds; K1, Vlg-Hau; 4, 19. Wood Bay Fm (Holtedahl 1914; Friend et al. 1966) Andrbe Land Gp; Verdalen, Skioldkollen, Orsabreen, Austfjorden mbrs; Stjordalen, Keltiefjellet, Lykta, Kapp Kjeldsen divs; D1, PraEms; 8, 10, 16. Woodfjorden Series (?Murashov & Mokin 1976) ~ Wood Bay Fm Wordiekammen Fm (Gee et al. 1952; SKS 199?) Dickson Land Sbgp; Tyrrellfjellet, Cadellfjellet, Kapitol, Morebreen, Idunfjellet mbrs; C2-Pl: Mos-Sak; 4, 17.

Wordiekammen, lower 1st mbr (Forbes et al. 1958) ~ Cadellfjellet

Mbr.

Hornsund. t

Wordiekammen, middle 1st mbr (Forbes et al. 1958)N lower

Tyrrellfjellet Mbr. t

t

t t t

t t

* ~t

Wordiekammen, upper 1st mbr (Forbes et al. 1958)~upper Tyrrellfjellet Mbr. Wulffberget Mbr (Murashov & Mokin 1976) Rivieratoppen Fm; D1, Lok; 8, 16. Wulffberget (marble) Fm (Harland 1985 after Gee) preoccupied so = Hornbaekpollen Mbr; Ptz; 8, 12. Wurmbrandegga Mbr (?Birkenmajer 1972) H6ferpynten Fm; Neoptz; 10, 12. Yellow sandstone (Andersson 1900) Kapp Hanna Fm; C2, MosKas; 11, 17. Ymerbuktafm (Pchelina 1983)~ lower part of Innkjegla Mbr of Carolinefjellet Fm. Aavatsmarkbreen Fm (Harland et al. 1993; Ohta et al. 1995) St Jonsfjorden Gp protolith, Ordovician and Pg metamorphosed; V, O; 9-14. Ymerdalen Gp (Krasil'shchikov & Livshits 1974; Smith & Armstrong 1976); Antarcticfjellet & Perleporten fms; 02-03; 11, 14. Younger Dolomite Series (Holtedahl 1920) = Perleporten Fm; O; 11, 14. Zeipelodden Mbr (Lauritzen 1981) Gipshuken Fm; PI: Sak; 5, 17. Zillerberget Mbr (Nagy 1970) Carolinefjellet Fm; K1, Alb; 4, 19.

References AARSGAARD,G. 1948. [An account of the mining activity on Svalbard in 1946]. Norges OJfisielle Statistikk, 10, 54-57. ABAKUMOV, S. A. 1965. [The Lower Hecla Hoek rocks of Ny Friesland Peninsula]. In: SOKOLOV, V. N. (ed.) Materiali po Geologii Shpitsbergena. NIIGA, Leningrad, 93-101. - - 1 9 7 6 a . ]Geological sketch of the environs of Krossfjorden, Island of Spitsbergen]. In: SOKOLOV,V. N. (ed.) Geology of Svalbard. A Collection of Articles. NIlGA, Leningrad, 000 000 - - 1 9 7 6 b . [Four foundations of the geology and metamorphism of northwestern Spitsbergen]. In: SOKOLOV, V. N. (ed.) Geology of Svalbard. A Collection of Articles. NIIGA, Leningrad, 22-31. - - 1 9 7 9 . Peculiar features of regional metamorphism of northwestern Spitsbergen. Norsk Polarinstitutt Skrifter, 167, 29-36. - - 1 9 8 3 . [Ultrabasites and gabbros of Botnehaugen, West Spitsbergen island]. In: Geology of Spitsbergen. Sevmorgeologiya, Leningrad, 63-73. - & CHAYKA, L. A. 1996. Geology and petrophysical properties of the rocks of northwestern Spitsbergen. In: DALLMANN,W. K. & KRASIL'SHCmKOV,A. A. (eds) Meddelelser, 139, 22 (Oslo 1996). --, GAVRILOV,B. P., KORCHINSKAYA,M. V., KRASIL'SHCH1KOV,A. A., MURASOV, L. G., PCHELINA,T. M., SEMEVSKIY,D. V., TEBENKOV,A. M. & TURCHENKO,S. I. 1990. In: GRAMBERG, I. S., KRASIL'SHCHJKOV,A. A. & SEMEVSKIY, D. V. (eds) Stratigraphic Lexicon of Spitsbergen Nedra, Leningrad. [In Russian] (For translation to English see Dallmann & Mork 1991). AI3DULLAH,W. H., MURCHISON, D., JONES, J. M., TELNAES, N. & GJELBERG,J. 1988. Lower Carboniferous coal depositional environments on Spitsbergen, Svalbard. In: MATTAVELLI,L. & NOVELLa, L. (eds) Advances in Organic Geochemistry 1987. Part 2: Analytical Geochemistry. Organic Geochemistry, 13, 953-964. ADADUROV,V. A. 1927. [Geological Review of Spitsbergen, its coal and market places]. In: SAMO~LOVICH,R. L., ADADUROV, V. A. & SIDOROV, A. N. (eds) The Coal Industry in Grumant (Spitsbergen). Leningrad. AFANAS'YEVA, O. B. 1991. [The Osteostracans of the USSR (Agnatha)]. Nauka, Moscow. AGA, O. J., DALLAND, A., ELVERHOI, A., THON, A. & WORSLEY, D. 1986. The Geological History of Svalbard. Evolution of an Archipelago. Statoil, Stavanger. AGDESTEIN,T. 1987. Kapp Hanna Formation. In: MORK, A. (ed.) Geological Excursion Guide to Bjornoya. IKU, Trondheim. Part 9, 1-30. AGUE, J. J. & MORRIS, A. P. 1985. Metamorphism of the Mfillerneset Formation, St. Jonsfjorden, Svalbard. Polar Research, 3, 93 106. AHLMANN, H. W. 1935. Scientific results of the Norwegian-Swedish Spitsbergen Expedition in 1934. Pt. V. The Fourteenth of July Glacier. Geografiske Annaler, 17, 167-2l 8. AHLMANN, H. W. 1941. [The coal fields of Spitsbergen]. Liner, 61, 231-233. - - 1 9 4 8 . Glaciological research on the North Atlantic coasts. Royal Geographical Research Series, No. 1. London. AIINEHSAZIAN,K. & VINCENZ,S. A. 1979. Magnetic properties of diabase sills of Agardhdalen, East Spitsbergen, Svalbard Archipelago (abstract). LOS (Transactions of the American Geophysical Union), 60, 247. /~kKEMAN, H. J. 1984. Notes on talus morphology and processes in Spitsbergen. Geografiske Annaler, 66A, 267-284. ALLAN, D. A. 1941. The Geology of Spitsbergen. Proceedings of the Liverpool Geological Society, 18, 37-48. ALLEN, J. R. L., DINELEY, D. L. & FRIEND, P. F. 1967. Old Red Sandstone basins of North America and Northwest Europe. In: OSWALD, D. H. (ed.) International Symposium on the Devonian System. Alberta Society of Petroleum Geologists, Calgary, 69-98. ALLEN, K. C. 1965. Lower and Middle Devonian spores of north and central Vestspitsbergen. Palaeontology, 8, 687-748. 1967. Spore assemblages and their stratigraphic application in the Lower and Middle Devonian of North and Central Vestspitsbergen. Palaeontology, 10, 280-297. 1973. Further information on the Lower and Middle Devonian spores from Dickson Land, Spitsbergen. Norsk Polarinstitutt Arbok 1971, 43-54. - - - 1 9 8 0 . A review of in situ Late Silurian and Devonian Spores. Review of Palaeobotany and Palynology, 29, 253-270. .~M, K. 1975. Magnetic profiling over Svalbard and surrounding shelf areas. Norsk Polarinstitutt Arbok 1973, 87-100. 1975. Aeromagnetic basement complex mapping north of latitude 64~ Norway. Norges Geologiske Undersokelse, Publication, 29, 351-374. AMUNDSEN, H. E. F., GRIFFIN, W. L. & O'REILLY, S. Y. 1987. The lower crust and upper mantle beneath northwestern Spitsbergen: evidence from xenoliths and geophysics. Tectonophysics, 139, 169-185. , & - - 1 9 8 8 . The nature of the lithosphere beneath northwestern Spitsbergen: xenolith evidence. In: KRISTOFFERSEN, Y. (ed.) Progress in Studies of the Lithosphere in Norway. Norges geologiske undersokelse, Special Publications, 3, 58-65. ANDERSEN, B. G. 1981. Late Weichselian ice sheets in Eurasia and Greenland. In: DENTON, G. H. & HUGHES, T. J. (eds) The Last Great Ice Sheets. Wiley, New York, 1-65. ANDERSEN, E. S., SOLHEIM, A. & ELVERHOX, A. 1992. Development of a subpolar margin, exemplified by the western margin of Svalbard (abstract). In: International Conference on Arctic Margins, 2-4 September 1992. ICAM, Anchorage, Alaska, 2.

- & 1994. Development of a glaciated continental margin: exemplified by the Western margin of Svalbard. In." Proceedings of International Conference on Arctic Margins. U.S. Department of the Interior, Minerals Management Service. Alaska Outer Continental Shelf Region. [O.C.S. study, MMS 94-0040], 155-160. ANDERSSON, G. 1910. Die jetzige und fossile Quatdrflora Spitzbergens als Zeugnis von Klimadnderungen des Klimas seit dem Maximum der letzten Eiszeit. Exekutivkomit6 des 11. Internationalen Geologen Kongresses, Stockholm. - - 1 9 1 7 . [Spitsbergen's coal resources and Sweden's coal needs. An economic geographic study]. En ekonomisk-geografisk studie. Liner, 37, 201-248. ANDERSSON,J. G. 1900. Uber die stratigraphie und tektonik der B~iren Insel. Bulletin of the Geological Institution of the University of Uppsala, 4, 243-280. - - 1 9 0 1 . Nyare litteratur om Beeren Eilands geologi. Geologiska F6reningens Stockholm Ffrhandlingar, 23, 219-230. ANDERTON, R. 1982. Dalradian deposition and the Late Precambrian-Cambrian history of the North Atlantic region: a review of the early evolution of the Iapetus Ocean. Journal of the Geological Society, London, 139, 421-431. ANDRI~, M. F. 1986. Dating slope deposits and estimating rates of rock wall retreat in northwest Spitsbergen by lichenometry. Geografiske Annaler, 68A, 65-76. --1986. Lichenom&rie et vitesse d'evolution des vesentes arctiques pendent l'Holocene (R6gion de la Baie du Roi, Spitsberg, 70~ Revue de G~omorphologie Dynamique, 2, 49-72. ANDRESEN, A. & WELBON, A. 1991. Structural observations across the Pretender lineament - implications for Late Paleozoic and Tertiary tectonic evolution in the Kongsfjorden area, western Spitsbergen (abstract). Norsk Geologisk Foreningens Vintermote Geonytt, 18, 12-14. , BERGH, S. G. & HAREMO,P. 1994. Basin inversion and thin-skinned deformation associated with the Tertiary transpressional West Spitsbergen Orogen. In: Proceedings of International Conference on Arctic Margins, U.S. Department of the Interior, Minerals Management Service. Alaska Outer Continental Shelf Region. [O.C.S. Study, MMS 94-0040], 161-166. , HAREMO, P. • BERGH, S. G. 1988. The southern termination of the Lomfjorden Fault Zone: evidence for Tertiary compression on east Spitsbergen. In: DALLMANN, W. K., OHTA, Y. 8r ANDRESEN, A. (eds) Tertiary Tectonics of Svalbard. Norsk Polarinstitutt, Report Series, 46, 75-78. --, -& 1988. The southern termination of the Lomfjorden Fault Zone: evidence for Tertiary compression on the East of Spitsbergen. In: DALLMANN, W. K., OHTA, Y. & ANDRESEN, A. (eds) Tertiary Tectonics of Svalbard. Norsk Polarinstitutt, Report Series, 46, 43-46. , , SWENSSON, E. & BERGH, S. G. 1992. Structural geology around the southern termination of the Lomfjorden Fault Complex, Agardhdalen, east Spitsbergen. In: DALLMANN, W. K., ANDRESEN, A. & KRILL, A. (eds) PostCaledonian Tectonic Evolution of Svalbard. Norsk Geologisk Tidsskrift, 72, 8342. ANDRULEaT, H., FREIWALD,A. & SCO_AFER,P. 1996. Bioclastic carbonate sediments on the southwestern Svalbard shelf. Marine Geology, 134, 163-182. ANON 1945. Report of the activities of Norges Svalbard- og Ishavs-undersokelser 1936-1944. Skrifter om Svalbard og Ishavet, 88, 1-71. ANTEVS, E. & NATHORST, A. G. 1917. Kohlenffihrender Kulm auf der B~iren-Insel. Geologiska F6reningens Stockholm Fdrhandlingar, 39, 649-663. ANTONSEN, P., ELVERHOI, A., DYPV1K, H. & SOLHEIM, A. 1991. Shallow bedrock geology of the Olga Basin area, northwestern Barents Sea. American Association of Petroleum Geologists, Bulletin, 75, 1178-1194. ARCHER, J. B. & FORTEY, R. A. 1974. Ordovician graptolites from the Valhallfonna Formation, northern Spitsbergen. Special Papers in Palaeontology, 13, 89-97. ARHUS, N. 1991. Dinoflagellate cyst stratigraphy of some Aptian and Albian sections from North Greenland, southeastern Spitsbergen and the Barents Sea. Cretaceous Research, 12, 209-225. --, ELVEBAKK,G. & KELLY, S. R. A. 1988. Palynostratigraphy of some BathonianHauterivian Sections in the Arctic with Emphasis on the Janusfjellet Formation Type Section, Spitsbergen. IKU, Report 23.1252.11/01/88. --, KELLY, S. R. A., COLLINS, J. S. H. & SANDY, M. R. 1990. Systematic palaeontology and biostratigraphy of two Lower Cretaceous condensed sections from the Barents Sea. Polar Research, 8, 165-194. ARKELL, W. J. 1956. Jurassic Geology of the World. Oliver & Boyd, Edinburgh. ARLOV, T. B. 1994. A short history of Svalbard. Polarhdndboker. Norsk Polarinstitutt, 95. ARMSTRONG, H. A. & SMaTH,M. P. The Ordovician of Bjornoya-lithostratigraphy and conodont biostratigraphy. Geological Magazine, in press. --, NAKREM, H. m. & OHTA, Y. 1986. Ordovician conodonts from the Bulltinden Formation, Motalafjella, central-western Spitsbergen. Polar Research, 4, 17-23. ARMSTRONG, T. E. 1958. The Russians in the Arctic; aspects of Soviet exploration and exploitation of the far north 1937-57. Methuen, New York. ASKLUND, B. 1956. Minutes from the conference on Eocambrian, extent and subdivision. Norsk Geologisk Tidsskrift, 36, 86-87. ATrdNSON, D. J. 1952. British geological work on Prins Karls Forland, Spitsbergen 1950 and 1951. Polar Record, 6, 527. - - 1 9 5 6 . The occurrence of chloritoid in the Hecla Hoek Formation of Prince Charles Foreland Spitsbergen. Geological Magazine, 93, 63-71. - - 1 9 6 0 . Caledonian Tectonics of Prins Karls Forland. In: International Geological Congress, Report of 21st Session, Part XIX, International Geological Congress, Norden, 17-27. -

-

.

478

REFERENCES

- - 1 9 6 2 . Tectonic control of sedimentation and the interpretation of sediment alternation in the Tertiary of Prince Charles Foreland, Spitsbergen. Geological Society of America Bulletin, 73, 343-364. --1963. Tertiary rocks of Spitsbergen. American Association of Petroleum Geologists, Bulletin, 47, 302-323. ATLASOV, I. P. 1964. [A new tectonic chart of the Arctic]. Doklady Akademii Nauk SSSR, 156(b), 1341-1342 [Translated by E. R. Hope]. --, YEO1AZAROV, B. K., DIBNER, V. D. and 8 others. 1964. Tectonic Map of the Arctic and Subarctic. In: Report of 22nd Session, International Geological Congress, Delhi 1964, 1-19, +folding map scale 1:30 000 000. AUSTEGARD, A. 1976. Earthquakes in the Svalbard area. Norsk Polarinstitutt flrbok 1974, 83-100. - - 1 9 8 2 . Velocity analysis of sonobuoy data from the northern Svalbard margin. Scientific Reports of the University of Bergen Seismological Observatory, 9, 1-25. --, LIKEN, O., STORDAL, T. & EVERTSEN, E. C. 1988. Deep-seismic sounding and crustal structure in the western part of Svalbard. In: DALLMAYN,W. K. OHTA. Y. & ANDRESEN, A. (eds) Tertiary Tectonics of Svalbard. Norsk Polarinstitutt, Report Series, 46, 89-90. AUSTER, V. & LENGNrN~, K. 1980. Ergebnisse und Anwendungsm6glichkeiten der geoelektromagnetischen und technischen Untersuchungen auf Spitszbergen. Geoddtische und Geophysikalische Verrffentlichungen, 1, 183-187. BACKLVND, H. 1907a. Les diabases du Spitzberg oriental. In: Mission Scientifique pour la mesure d'un arc de mdridien au Spitzberg. Mission Russe, 2(9), 1~9. - - 1 9 0 7 b . Ober einige Diabase aus arktischen Gebiet. Tschermaks Mineralogische und Petrographische Mitteilungen, 26, 357-390. - - 1 9 0 8 . Observations dans le Spitzberg central. In: Mission Scientifique pour la mesure d'un arc de m~ridien au Spitsberg entrepr, en 1899-1901 sous les auspices des gouvernements russe et suddois. Mission Russe, 2(9), 1-28, with map of Billefjorden to Storfjorden, 1 : 168 000. - - 1 9 1 1 . Ober einige Olivinknollen aus der Lava von Woodbay Spitzbergen. Skrifter udgivne af Videnskabsselskabet i Kristiania. Mat.-Naturv, 16, 1-11. On the eastern part of the Arctic basalt plateau. Acta Aeademiae .4 dboensis Mathematica et Physiea, 1, 1-53. 1921. [Tectonics and isostasy on Spitsbergen]. Geologiska Frreningens Stockholm Ffrhandlingar, 43, 397-402. 1930. Contributions to the Geology of North East Greenland. Meddelelser om Gronland, 74, 207-296. - - 1 9 4 2 . Probleme der arktischen Plateaubasalte. VerOffentliehungen der Deutschen der Wissenschaften Institut, Kopenhagen, Reihe L. Arktis, 3, 1-18. B~CKSTRrM, H. 1905. Ein Kugelgranit von Spitzbergen. Geologiska Frreningens Stockholm Ffrhandlingar, 27, 254-459. BACKSTROM, S. A. & NAGY, J. 1985. Depositional history and fauna of a Jurassic phosphorite conglomerate (the Brentskardhaugen Bed) in Spitsbergen. Norsk Polarinstitutt Skrifter, 183, 1 61. BADEN-PowELL, D. F. W. 1939. On further collections of Quaternary fossils from Spitsbergen. Geological Journal, 76, 337-347. BAILEY, E. B. 1929. The Palaeozoic mountain systems of Europe and America. Report of the British Association jbr the Advancement Science 1928, 57-76. -t~ HOLTEDAHL,O. 1938. Northwestern Europe, Caledonides. Regionale Geologic der Erdo, 2. Palaeozoische Tafeln. und Gebirge, Absch. I l, (Leipzig). BAIN, G. W. 1960. Climatic zones of the Paleozoic era. In: Report of the International Geological Congress, 21st Session Norden 1960, 84 93. BAKER, B. H., FORBES, C. L. & HOLLAND, M. F. W. 1952. Fossiliferous strata at Kapp Scania, Daudmannsoyra, Vest Spitsbergen. Geologieal Magazine, 89, 303-304. BAKKEN, K. A., L~BERG, R. & THEIS, N. 1994/5. Residual oils and other hydrocarbons from the Barents sea: grouping and sourcing. In: MANNING, D. A. C. (ed.) Organic Geochemistry. Manchester University Press, Manchester, 11 13. BALASHOV, Yu. A., FEDOTOV, Z. A., SKUFKIN, P. K., SHARKOV, I. V., KRAVCHENKO, M. P., SHERSTOBITOVA, G. M. ,~ UL'YANENKO, N. A. 1992. [Evolution of volcanism in the Pechenga sedimentary-volcanic unit from Rb/Sr isotope data]. Tezisy XIII Simposiuma geockimii isotopov, 16 17. -, LARIONOV, A. N., GANNIBAL, L. F., SIROTKIN, A. N., TEBEN'KOV, A. M., RYT3N~ENEN, G. I. & OnTa, Y. 1993. An Early Proterozoic U-Pb zircon age from an Eskolabreen Formation gneiss in southern Ny Friesland, Spitsbergen. Polar Research, 12, 147-152. , TEBEN'KOV,A. M., OHTA, Y., LARIONOV,A. N., SIROTKIN,A., GANNIBAL,L. F. & RYUN~ENEN, G. 1. 1995. Grenvillian U P b zircon ages of quartz porphyry and rhyolite clasts in a metaconglomerate at Vimsodden, southwestern Spitsbergen. Polar Research, 14, 291-302. - - , PEUCAT, J. J., TEBEN'KOV,A. M., OHTA, Y., LARIONOV,A. N. & SIROTKIN,A. N. 1996a. Additional Rb-Sr and single grain zircon dating of the granitoid rocks from Albert I Land, NW Spitsbergen. Polar Research, 15, 153 165. ---, . . . . 8r BJORNERUD, M. 1996b. Rb-Sr whole rock and U-Pb zircon datings of the granitic-gabbroic rocks from the Skfilfjellet Subgroup, southwest Spitsbergen. Polar Research, 15, 167-181. BALCHIN, W. G. V. 1941. The raised features of Billefjord and Sassenfjord West Spitsbergen. Geographical Journal, 97, 364-376. BALKWILL, H. R. 8r FOX, F. G. 1982. Incipient rift zone, western Sverdrup Basin, Arctic Canada. In: EMBRY, A. F. & BALKWILL,H. R. (eds) Arctic Geology and Geophysics. Memoirs of the Canadian Society of Petroleum Geologists, 8, 171-187. BAMBER, J. L. 8r DOWDESWELL, J. A. 1990. Remote-sensing studies of Kvitoyjokulen, an ice cap on Kvitoya, north-east Svalbard. Journal of Glaciology, 36, 75-81. -

- -

-

1

9

2

0

.

BANNO, S., H1ROI, Y. & HIRAJIMA, T. 1990. Svalbard Geological Expedition, Kyoto University, Japan 1983. In: TATSUMI,T. (ed.) The Japanese Scientific Expeditions to Svalbard 1983-1988. Kyoikusha, Tokyo, 71-114. BARANOWSKLS. 1977. The sub-polar glaciers of Spitsbergen seen against the climate of the region. Acta Universitatis Wratislaviensis, 410. BARBAROUX, L. H. 1966a. Contributions fi l'rtude tectonique de la Presqu' ile de Brogger (Spitsberg). Bulletin de la Socidtd G~ologique de France, 8, 560-566. - - 1 9 6 6 b . De l'&ude statistique des blocs erratiques, riv sud du Kongsfjord, Spitsberg. C.N.R.S.R.C.P., 42, 239-244. - - 1 9 6 8 a . Les formations "detritiques-corraligenes" Carboniferes de la presqu'ile de Brogger, baie du R o i - Vestspitsbergen. Bulletin de la Soci~td Gdologique de France, 9, 714-722. - - 1 9 6 8 b . Superposition de styles tectoniques et virgation forcre au Vestspitsbergen (79 lat nord). Comptes Rendus de l'Academie des Sciences, Paris, Series D, 266, 871-874. - - 1 9 7 0 . Etude gOologique et sddimentologique de la presqu'isle de Brogger. CNRS Spitsberg, Mission Frangaise 1966, Paris. & BISSET, I. 1968. Le karst de Sarsoyra (rive nord Aavatmarksbre) Vest Spitsbergen. Norois, 57, 97-103. BARKER, A. J. ,~ GAYER, R. A. 1985. Caledonide-Appalachian tectonic analysis and evolution of related oceans. In: GAYER, R. A. (ed.) The Tectonic Evolution of the Caledonide-Appalachian Orogen. Braunschweig/Wiesbaden, Friedrich Viewig, 126-165. BARKHATOV, B. P. 1970. [Main stages of tectonic development of the Spitsbergen archipelago]. Leningrad University, Vestnik Geologiya Geogratiya, 6, 157-159 [in Russian]. BARKHATOV,D. B. 1984. [New data on the pre-Vendian folding and magmatism of the western part of the Spitsbergen Archipelago]. Vestnik Leningra~'kogo Gosudarstvennogo Universiteta, Set. Geologiya, Geografiya, 18, 67-69. - - 1 9 8 5 . New data on the pre-Vendian orogeny and magmatism in western Spitsbergen. International Geology Review, 27. BARON, S. H. 1986. Did the Russians discover Spitsbergen? Osteuropa-Institut an der Freien Universitdt Berlin, Historiche Verdffentlichungen, 38, 42-63. BARR, K. W. 1960. The Old Red Sandstone of eastern Ekmanfjorden (DINELEY, Geological Magazine, 97(1), 18-32, 1960): correspondence. Geological Magazine, 97, 263-264. BARSCH, D., GUDE, M., MAUSBACHER,R., SCHUKRAFT,G. & SCHULTE,A. 1994. Recent fluvial sediment budgets in glacial and periglacial environments, NW Spitsbergen (with 6 figures and 2 tables). Zeitschrift ffir Geomorphologie, 97, 111-122. BASSET, M. G. • OWENS, R. M. 1996. Discussion on a revision of Ordovician Series and stage divisions from the historical type area. Geological Magazine, 133, 767-772. BATES, O. E. B. & SCHWARZACHER, W. 1958. The geology of the land between Ekmanfjorden and Dicksonfjorden in central Vestspitsbergen. Geological Magazine, 95, 219-233. BATURIN, A. B. & NECHKHAYEV, S. A. 1989. [Deep structure of the Spitsbergen marginal plateau in the northeastern part of the Greenland Sea]. Doklady ,4kademii Nauk SSSR, 306, 925-930. BATURIN, D. G. 1986. [The western continental margin of the Svalbard archipelago. Tectonics and sedimentation. Geology of the sedimentary cover of Svalbard. Collection of scientific papers]. In: Sbornik nauchnykh trudov. Sevmorgeologiya, Leningrad, 125 135. - - 1 9 8 8 . [Structure and evolution of the continental margin of the Eurasia basin between the archipelagos of Spitsbergen and Franz Josef Land]. Doklady Akademii Nauk SSSR, 299, 419 423. , SAVOSTIN,I. & FEDUKHINA,T. 1992. Basement structure of the West Spitsbergen continental margin, Greenland Sea (abstract). In: International Conference on Arctic margins, 2-4 September 1992. ICAM, Anchorage, Alaska, 4. , SAVOSTIN,L. t~ YUNOV, A. 1992. Cenozoic tectonics and seismostratigraphy of the West Spitsbergen continental margin (abstract). Norsk Geologisk Tidsskr~t, 72, 136. BAUMHAUER,R. & GLASER, U. 1994. Zur Entwicklung der postglazialen Sedimentation im Bereich des Liefde-fjordes, NW-Spitzbergen (mit 4 Figuren. ZeitschHft ffir Geomorphologie, 97, 65 74. BAYLY, M. B. 1957. The Lower Hecla Hock rocks of Ny Friesland, Spitsbergen. Geological Magazine, 94, 377-392. BEACH,A. & ROWAN,M. G. 1992. Techniques for the geometrical restoration of sections: an example from the Bjornoya Basin, Barents Sea shelf. In: LARSENR. M., BREKKE, H., LARSEN, B. Z. ,~z TAELERAAS,E. (eds) Structural and Tectonic" Modelling and its Application to Petroleum Geology, Norwegian Petroleum Society (NPF), Special Publication, Part 1. Proceedings of Norwegian Petroleum Society Workshop, 18~0 October 1989, Stavanger, Norway. Elsevier, Amsterdam, 269-276. BEGE, W. 1960. WissenschaJHiche Beobachtungen auf dem Nordostland yon Spitzbergen 1944-1945, Vol. 10(10), Beitrfige von Arther Baumann. Berichte des Deutschen Wetterdienstes [English Summary]. BELYANKIN,D. & VLODAVETS,V. 1931. [On the granites of Spitsbergen and the basalts of Franz Josef Land]. Transactions of the Institute for study of the North, Moscow, Leningrad, 137-178. BENNIKE, O. & HEDEN)~S, L. 1995. Early Holocene land floras and faunas from Edgeoya, eastern Svalbard. Polar Research, 14, 205-214. BERGE, G. 1997a. Discoveries on the Norwegian Continental Shelf. Norwegian Petroleum Directorate, Stavanger. - - 1 9 9 7 b . The Petroleum Resources of the Norwegian Continental Shelf. Norwegian Petroleum Directorate, Stavanger. BERGER, S. ,~ BREKKE, A. 1980. Comparison of annual variations observed in the Earth's magnetic field, Tromso, Ny-,~lesund and Bjornoya. Geophysica Norvegica, 32, 1-6. -

-

REFERENCES BERGH, S. G. & ANDRESEN, A. 1990. Structural development of the Tertiary fold-andthrust belt in east Oscar II Land, Spitsbergen. Polar Research, 8, 217-236. , BRAATHEN,A. & ANDRESEN,A. 1997. Interaction of basement-involved and thinskinned tectonism in the tertiary fold-thrust belt of central Spisbergen, Svalbard. American Association of Petroleum Geologists Bulletin, 81, 637-661. , OHTA, Y., ANDRESEN, A., MAHER, H. D., BRAATHEN,A. ~z DALLMANN, W. K. 1993. Geological map of Svalbard I:100000, sheet BSG. St Jonsfjorden, preliminary edition. Norsk Polarinstitutt. BERGSAGER, E. 1986a. Exploration activity and prospectivity in the Barents Sea. Norwegian Oil Review, 12, 34-47. - - 1 9 8 6 b . Future petroleum potential of the Barents Sea. In: SPENCER, A. M. et al. (eds) Habitat of Hydrocarbons on the Norwegian Continental Shelf Graham & Trotman, London, 339-354. BERGSTROM, S. M. 1989. Significance of conodonts from the Valhallfonna Formation (Lower-Middle Ordovician) of Ny Friesland, Spitsbergen. Geological Society of America, Abstracts with Programs, 21. BERNARD-GRIFFITHS,J., PEUCAT,J. J. t~ OHTA, Y. 1993. Age and nature of protoliths in the Caledonian blue schist-eclogite complex of western Spitsbergen: A combined approach using U-Pb, Sm-Nd and REE whole rock system. Lithos, 30, 81-90. BERR, M. R. 1914. Les gisements de Charbon du Spitsberg. Annales du Mines, Paris, March, 1-75. BHARADWAY, D. C. & VENKATACHALA,B. S. 1961. Spore assemblage out of a Lower Carboniferous shale from Spitsbergen. The Palaeobotanist, 10, 18-47. BIDDLE, K . Z . & CHRISTIE-BLICK,N. (eds) 1985. Strike-slip Deformation, Basin Formation, and Sedimentation. Special Publications of the Society of Economic Paleontologists and Mineralogists, 37. BIDGOOD,D. E. T. & HARLAND,W. B. 1961. Palaeomagnetism in some East Greenland sedimentary rocks. Nature, 189, 633-634. BIERNAT, G. & BIRKENMAJER,K. 1981. Permian brachipods from the base of the Kapp Starostin Formation at Polakkfjellet, Spitsbergen. In: BIRKENMAJER, K. (ed.) Geological Results of the Polish Spitsbergen Expeditions. Studia Geologica Polonica, 73(12), 7-24. - ~L SZYMANSKA,W. 1982. Palaeontological Spitsbergen studies. Palaeontologica Polonica, 43, 1-140. BIRKLUND, T. & HAKANSSON, E. 1983. The Cretaceous of North Greenland: a stratigraphic and biogeographic analysis. Zitteliana, 10, 7-25. , THtJSU, B. & VICRAN, J. 1978. Jurassic-Cretaceous biostratigraphy of Norway, with comments on the British Rasenia cymodoce zone. Palaeontology, 21, 31-63. BIRKENMAJER, K. 1958a. Preliminary report on the stratigraphy of the Hecla Hoek Formation in Wedel-Jarlsberg Land, Vestspitsbergen. Bulletin de l'Acaddmie Polonaise des Sciences. S~rie des Sciences Chimiques, G~ologiques et Gdographiques, 6, 143 150. - - 1 9 5 8 b . Preliminary report on the raised marine features in Hornsund, Vestspitsbergen. Bulletin de l'Acaddmie Polonaise des Sciences. Sdrie des Sciences Chimiques, Gdologiques et G~ographiques, 6, 151 157. - - 1 9 5 9 a . Report on the geological investigations of the Hornsund area, Vestspitsbergen in 1958. Part I. The Hecla Hoek Formation. Bulletin de l'Acaddmie Polonaise des Sciences. Sdr& des Sciences Chimiques, Gdologiques et Gdographiques, 7, 129-136. - - 1 9 5 9 b . Report on the geological investigations of the Hornsund area, Vestspitsbergen in 1958. Part II. The post-Caledonian succession. Bulletin de l'AcadOmie Polonaise des Sciences. SOrie des Sciences Chimiques, Gdologiques et Gdographiques, 7, 191-196. - - 1 9 5 9 c . Report on the geological investigations of the Hornsund area, Vestspitsbergen in 1958. Part Ill. The Quaternary Geology. Bulletin de l'Acad~mie Polonaise des Sciences. S~rie des Sc&nces Chimiques, Gdologiques et Gkographiques, 7, 197-202. - - 1 9 6 0 a . Geological Sketch of the Hornsund Area (Supplement to the guide for excursion AI6: Aspects of the Geology of Svalbard). International Geological Congress, Norden. - - 1 9 6 0 b . Relation of the Cambrian to the Precambrian in Hornsund, Vestspitsbergen. In: International Geological Congress, Report of 21st Session, Part VIII. International Geological Congress, Norden, 64~4. - - 1 9 6 0 c . Recent vertical movements of Spitsbergen. In: International Geological Congress, Report of 21st Session, Part XXL International Geological Congress, Norden, 281-294. - - 1 9 6 0 d . Raised marine features of the Hornsund area, Vestspitsbergen. Studia Geologia Polonica, 5, 1-95. --1964a. Devonian, Carboniferous and Permian formations of Hornsund, Vestspitsbergen. In: B1RKENMAJER,K. (ed.) Geological Results of the 195~1958, 1959, 1960 Spitsbergen Expeditions, Part 3. Studia Geologica Polonica, 11, 47-124. - - 1 9 6 4 b . Quaternary geology of Treskelen, Hornsund, Vestspitsbergen. Studia Geologica Polonica, 11, 185-196. - - 1 9 6 5 . Some sedimentological observations in the Old Red Sandstone at Lykta, Vestspitsbergen. Norsk Polarinstitutt .4rbok 1963, 137 150. - - 1 9 6 6 a . Lower Cretaceous tidal deposits of central Vestspitsbergen. Norsk Polarinstitutt .,]rbok 1964, 73-85. - - 1 9 7 2 a . Megaripples and phosphorite pebbles in the Rhaeto-Liassic beds south of Van Keulenfjorden, Spitsbergen. Norsk Polarinstitutt Jlrbok 1970, 117-127. - - 1 9 7 2 b . Tertiary history of Spitsbergen and continental drift. Acta Geologiea Polonica, 22, 193-218. - - 1 9 7 2 c . Cross bedding and stromatolites in the Precambrian H6ferpynten Dolomite Formation of Sorkapp Land, Spitsbergen. Norsk Polarinstitutt flrbok 1970, 128 145. - - 1 9 7 2 d . Alpine fold belt of Spitsbergen. In: 24th lnternationaI Geological Congress, Canada 1972. Reports section 3. International Geological Congress, 282-292. - - 1 9 7 5 a . Jurassic and Lower Cretaceous sedimentary formations of SW Torell Land, Spitsbergen. Studia Geologica Polonica, 44, 7-43.

479

- - 1 9 7 5 b . Caledonides of Svalbard and plate tectonics. Bulletin of the Geological Society of Denmark, 24, 1 19. - - 1 9 7 7 a . Trace fossil evidence for predation on trilobites from Lower Cambrian of south Spitsbergen. Norsk Polarinstitutt ~lrbok 1976, 187-194. 1977b. Triassic sedimentary formations of the Hornsund area, Spitsbergen. In: BIRKENMAJER, K. (ed.) Geological Results of the Polish Spitsbergen Expeditions. Part 8. Studia Geologica Polonica, 51, 7-74. --1978a. Cambrian succession in South Spitsbergen. In: BIRKENMAJER,K. (ed.) Geological Results of Polish Expeditions, Part 9. Studia Geologica Polonica, 59, 7-46. 1978b. Ordovician succession in South Spitsbergen. In: BIRKENMAJER,K. (ed.) Geological Results of Polish Expeditions, Part 9. Studia Geologica Polonica, 59, 47 81. - - 1 9 7 8 c . [Polish-American paleomagnetic investigations in Spitsbergen 1974-1977]. Przeglad Geologiczny, 8, 470-473. --1979a. Lower Cretaceous twin dolerite sills at Agardhbukta (east Spitsbergen) and the problem of thermal metamorphism of Mesozoic palynomorphs. In: BIRKENMAJER, K. (ed.) Results of the Polish Spitsbergen Expeditions' Part 10. Studia Geologica Polonica, 60, 57-63. - - 1 9 7 9 b . Channeling and orientation of rugose corals in shallow marine Lower Permian of south Spitsbergen. In: BIRKENMAJER, K. (ed.) Results of the Polish Spitsbergen Expeditions Part 10. Studia Geologica Polonica, 60, 45-55. 1979c. Palaeotransport and source of early Carboniferous fresh-water elastics of south Spitsbergen. In: BIRKENMAJER,K. (ed.) Results of the Polish Spitsbergen Expeditions Part I0. Studia Geologica Poloniea, 60, 39-43. - - 1 9 8 0 a . Jurassic-Lower Cretaceous succession at Agardhbukta, east Spitsbergen. In: B1RKENMAJER,K. (ed.) Geological Results of the Polish Spitsbergen Expeditions Part 11. Studia Geologica Polonica, 66, 35 52. - - 1 9 8 0 b . Ice-cored talus and subsurface drainage at Agardhbukta, east Spitsbergen. In: BIRKENMAJER,K. (ed.) Geological Results of the Polish Spitsbergen Expeditions Part 11. Studia Geologica Polonica, 66, 53-59. - - 1 9 8 1 . The geology of Svalbard, the western part of the Barents Sea, and the continental margin of Scandinavia. In: NAIRN, A. E. M. CHURKIN, M. JR. STEHLI, F. G. (eds) The Arctic Ocean, The Ocean Basins and Margins, Part 5. Plenum, New York, 265-329. - - 1 9 8 4 a . Sedimentary features of the Helvetiafjellet Formation (Barremian) at Agardhbukta, East Spitsbergen. In: Geological Results of the Polish Spitsbergen Expeditions Part 13. Studia Geologica Polonica, 80, 59-69. - - 1 9 8 4 b . Facies variation in the Helvetiafjellet Formation (Barremian) of Torrell Land, Spitsbergen. In: BIRKENMAJER, K. (ed.) Geological Results of the Polish Spitsbergen Expeditions Part 13. Studia Geologiea Polonica, 80, 71-90. - - 1 9 8 4 e . Mid-Carboniferous red beds at Hornsund, South Spitsbergen: their sedimentary environment and source area. In: BIRKENMAJER,K. (ed.) Geological Results of the Polish Spitsbergen Expeditions, Part 13. Studia Geologica Polonica, 80, 2 2 3 . - - 1 9 8 4 d . Cyclic sedimentation in mixed alluvial to marginal-marine conditions: the Treskelodden Formation (?Upper Carboniferous and Lower Permian) at Hornsund, South Spitsbergen. In: Geological Results of the Polish Spitsbergen Expeditions, Part 13. Studia Geologica Polonica, 80, 25-46. - - 1 9 8 4 e . Regressive deposition in the De Geerdalen Formation (Rhaeto-Liassic) at Agardhbukta, east Spitsbergen. In: Geological Results of the Polish Spitsbergen Expeditions, Part 13. Studia Geologica Polonica, 80, 47-58. - - 1 9 8 5 . The geology of Svalbard, the western part of the Barents Sea and the continental margin of Scandinavia. In: GEE, D. G. & STURT, B. A. (eds) The Caledonide Orogen Scandinavia and Related Areas. Wiley, Chichester, 265-329. - - 1 9 8 6 . Tertiary tectonic deformation of Lower Cretaceous dolerite dykes in a Precambrian terrane, south-west Spitsbergen. In: BIRKENMAJER, K. (ed.) Geological Results of the Polish Spitsbergen Expeditions', Part XIV. Studia Geologica Polonica, 89, 31-44. - - 1 9 9 0 a . Non-glacial origin of the Slyngfjellet Conglomerate (Upper Proterozoic), South Spitsbergen. Polish Polar Research, 11, 301-315. - - 1 9 9 0 b . Geology of the Hornsund area. Scale 1: 75,000. University of Silesia, Katowice. - - 1 9 9 1 a . Origin of the Vimsodden tilloids (Early Proterozoic), South Spitsbergen. Bulletin of the Polish Academy of,"Sciences, 39, 39-46. - - 1 9 9 1 b . Geological map of the Hornsund area. Scale 1: 75,000. Polish Academy of Sciences, Katowice. - - 1 9 9 1 c . The Jarlsbergian unconformity (Proterozoic/Cambrian boundary) and the problem of Varangian tillites in south Spitsbergen. Polish Polar Research, 12, 269-278. - - 1 9 9 2 a . Precambrian succession at Hornsund, South Spitsbergen: a lithostratigraphic guide. Studia Geologica Polonica, 98, 7-66. - - 1 9 9 2 b . Polish geological research in Svalbard. Earth Sciences History, 11, 81-87. - - 1 9 9 3 a . Some current geological problems in the Precambrian and Lower Palaeozoic of Sorkapp Land, South Spitsbergen. Zeszyty Naukowe Uniwersytetu Jagiellonskiego, 94, 29-37. - - 1 9 9 3 b . Redefinition of parts of the Vimsodden Subgroup and the Deilegga Group (Proterozoic), SE Wedel Jarlsberg Land, Spitsbergen. Bulletin of the Polish Academy of,"Sciences, 41, 137-159. - - 1 9 9 3 c . Tertiary and Cretaceous faulting in a Proterozoic metamorphic terrain, S.E. Wedel Jarlsberg Land, Spitsbergen. Bulletin of the Polish Academy of Earth Sciences, 41, 181-189. - - 1 9 9 4 . Variscan deformation phases in southern Spitsbergen. Journal of the Czech Geological Society, 39, 10-11. - & BROWN, B. W. 1970. Zn-enriched whale bones on raised marine terraces at Hornsund, Spitsbergen. Norsk Polarinstitutt Arbok 1969, 44-54. - & CZARNIECKI, S. 1960. Stratigraphy of marine Carboniferous and Permian deposits in Hornsund (Vestspitsbergen), based on brachiopods. Bulletin de l'Acad~mie Polonaise des Sciences. Sdrie des Sciences G~ologiques et GOographiques, 8, 203-209.

480 -

REFERENCES 8/: FEDOROWSKI,J. 1980. Corals of the Treskelodden Formation (Lower Permian) at Triasnuten, Hornsund, south Spitsbergen. In: BIRKENMAJER,K. (ed.) Geological

-

Results of the Polish Spitsbergen Expeditions Part 11. Studia Geologica Polonica, 66, 7-27. & JERZMANSKA, A. 1979. Lower Triassic shark and other fish teeth from Hornsund, south Spitsbergen. In: BIRKENMAJER, K. (ed.) Results of the Polish Spitsbergen Expeditions Part 10. Studia Geologica Polonica, 60, 7-37. LOGAN, A. 1969. On the fauna and age of the Cancrinella Limestone (Permian) at Kopernikusfjellet, Vestspitsbergen. Norsk Polarinstitutt Arbok I967, 28-45. 8r MORAWSKI, T. 1960. Dolerite intrusions of Wedel-Jarlsberg Land, Vestspitsbergen, ln: BIRKENMAJER, K. (ed.) Geological Results of the Polish 195~1958 Spitsbergen Expedition, Part L Studia Geologica Polonica, 4, 103-123. & NAREBSKI, W. 1960. Precambrian amphibolite complex and granitization phenomena in Wedel-Jarlsberg Land, Vestspitsbergen. In: BIRKENMAJER,K. (ed.) Geological Results of the Polish 1957-1958 Spitsbergen Expedition, Part I. Studia Geologica Polonica, 4, 37-82. & 1963. Dolerite drift blocks in marine Tertiary of Sorkapp Land and some remarks on the geology of the eastern part of this area. Norsk Polarinstitutt Arbok 1962, 68-79. & OLSSON, I. U. 1970. Radiocarbon dating of raised marine terraces at Hornsund, Spitsbergen and the problem of land uplift. Norsk Polarinstitutt Arbok 1969, 17-43. & ORLOWSKI,S. 1977. Olenellid fauna from the base of Lower Cambrian sequence in south Spitsbergen. Norsk Polarinstitutt ~trbok 1976, 167-185. 8r PUGACZEWSKA,H. 1975. Jurassic and Lower Cretaceous marine fauna of SW Torell Land, Spitsbergen. Studia Geologica Polonica, 44, 45-88. 8z TRAMMER, J. 1975. Lower Triassic conodonts from Hornsund, South Spitsbergen. Acta Geologica Polonica, 25, 299 308. -8r TURNAU, E. 1962. Lower Carboniferous of the so-called Wijde Bay Series in Hornsund, Vestspitsbergen. Norsk P olarinstitutt ,4rbok 1961, 41-61. -& WIERZBOWSKI, A. 1991. New Kimmeridgian ammonite fauna from East Spitsbergen and its phyletic significance. Polar Research, 9, 169-180. 8r WOJCIECHOWSKI,J. 1964. On the age of ore-bearing veins of the Hornsund area, Vestspitsbergen. In: BIRKENMAJER,K. (ed.) Geological Results of the Polish 1957-1958, 1959, 1960 Spitsbergen Expeditions, Part 3. Studia Geologica Polonica, 11, 179-184. , FEDOROWSKI,J. 8r SMULIKOWSKI,W. 1972. Igneous and fossiliferous sedimentary drift pebbles in marine Tertiary of Torell Land, Spitsbergen. Norsk Polarinstitutt flrbok 1970, 146-164. , FRANKIEW1CZ,J. K. 8r WAGNER, M. 1992. Late Proterozoic anthracite coals from the Hornsund area, south Spitsbergen. Polish Polar Research, 13, 71-90. , NAGY, J. & DALLMANN,W. K. 1992. Geological map ofSvalbard 1:100 000. Sheet C12G Markhambreen. Norsk Polarinstitutt Temakart. No. 22. , PUGACZEWSKA, H. & WIERZBOWSKI, A. 1982. The Janusfjellet Formation (Jurassic-Lower Cretaceous) at Myklegardfjellet, East Spitsbergen. In: BIERNAT, G. 8L SZYMANSKA,W. (eds) Palaeontological Spitsbergen Studies. Palaeontologica Polonica, 43, 107-140. BlSSET, C. B. 1927. Geological notes. British Arctic Expedition 1925. In: WORSLEY, F. A. (ed.) Under Sail in the Frozen North. London, 278-289. - - 1 9 3 0 . Geological notes on North-East Land and Franz Josef Land. Transactions of the Edinburgh Geological Society, 12, 196 206. BJAERKE, T. 1975. Atlas of Palynomorphs from the Upper Triassic of Hopen. N T N F K Continental Shelf Project, Trondheim. - - 1 9 7 7 . Mesozoic palynology of Svalbard II. Palynomorphs from the Mesozoic sequence of Kong Karls Land. Norsk Polarinstitutt Arbok 1976, 83 120. 1978. Mesozoic palynology of Svalbard III. Dinoflagellates from the Rurikfjellet Member, Janusfjellet Formation (Lower Cretaceous) of Spitsbergen. Palinologia, l, 69~79. - - 1 9 8 0 a . Mesozoic palynology of Svalbard IV. Toarcian dinoflagellates from Spitsbergen. Palynology, 4, 57-78. - - 1 9 8 0 b . Mesozoic palynology of Svalbard V. Dinoflagellates from the Agardhfjellet Member (Middle and Upper Jurassic) in Spitsbergen. Norsk Polarinstitutt Skrifter, 172, 145-167. & DYPVIK, H. 1977. Sedimentological and palynological studies of Upper Triassic-Lower Jurassic sediments in Sassenfjorden, Spitsbergen. Norsk Polar&stitutt flrbok 1976, 131-150. & MANUM, S. B. 1977. Mesozoic palynology of Svalbard I. The Rhaetian of Hopen, with a preliminary report on the Rhaetian and Jurassic of Kong Karls Land. Norsk Polarinstitutt Skrifter, 165, 1-48. -& Tnust3, B. 1976. Cretaceous palynomorphs from the Spitsbergen-banken, NW Barents Shelf. Norsk Polarinstitutt .4rbok 1974, 258 262. , EDWARDS, M. B. 8r THUSU, B. 1976. Microplankton from the JanusfjeUet Subgroup (Jurassic-Lower Cretaceous) at Agardhfjellet, Spitsbergen. A preliminary report. Norsk Polarinstitutt ~lrbok 1974, 63-68. BJELDJANKIN,D. E. 8r VLODAVETZ,W. 1931. ()bet die Granite der Insel Spitzbergen und fiber Basalte des Franz-Joseph-Landes. Arbeiten des Institutes zur Erforschung des Nordens Lief, 50. BJORLYKKE, K., BUE, B. & ELVERHOI, A. 1978. Quaternary sediments in the northwestern part of the Barents Sea and their relation to the underlying Mesozoic bedrock. Sedimentology, 25, 227-246. , ELVERHOI,A. & MALM, A. O. 1979. Diagenesis in Mesozoic sandstones from Spitsbergen and the North S e a - a comparison. Geologische Rundschau, 68, 1152-1171. BJORNERUD, M. 1989. Mathematical model for folding of layering near rigid objects in shear deformation. Journal of Structural Geology, 11, 245 254. - - 1 9 9 0 . An Upper Proterozoic unconformity in northern Wedel Jarlsberg Land, southwest Spitsbergen: lithostratigraphy and tectonic implications. Polar Research, 8, 127-139. -

-

-

-

-

-

-

-

-

-

-

-

-

-

-

-

-

-

&

- - 1 9 9 2 . Evidence for extensive post-Caledonian karst development in southwestern Spitsbergen. Geological Magazine, 129, 465-469. --, CRADDOCK, C. & WILLS, C. J. 1990. A major late Proterozoic tectonic event in southwestern Spitsbergen. Precambrian Research, 48, 157-165. - - , DECKER, P. L. & CRADDOCK,C. 1991. Reconsidering Caledonian deformation in southwest Spitsbergen. Tectonics, 10, 171-190. BJOR_OY, M. 1977. Organic Geochemistry Applied to Mesozoic Shales from Svalbard. IKU, Trondheim, Publication No. 94. & HALL, P. B. 1983. A rich Middle Triassic source rock in the Barents Sea area. In: Offshore Technology Conference. Houston, TX, 379-387. -& VIGRAN,J. O. 1979. Organic geochemistry of the Lower Cretaceous of Andoya and Spitsbergen. In: Norwegian Sea Symposium arranged by Norwegian Petroleum Society, Tromso 27-29 August 1979, NSS/25. Norwegian Petroleum Society, Tromso, 1-20. & 1980a. Geochemical study of the organic matter in outcrop samples from Agardhfjellet, Spitsbergen. In: DOUGLAS,A. G. & MAXWELL, J. R. (eds) Advances in Organic Geochemistry 1979. Pergamon, Oxford, 141-147. -& - - 1 9 8 0 b . Organic Geochemistry of Drift Material fi'om Svalbardbanken. IKU, Report P-160/5/80. , LEYTHAEUSER,D., MACKENZIE, A. S., SCHAEFFER, R. G. & ALTEBAUMER,F. J. 1981. Recognition of migration and its effects within two core holes in shale/ sandstone sequencesfrom Svalbard, Norway. IKU, Report P-289/1/81. , MORK, A. • VIGRAN, J. O. 1980. Organic Geochemistry of Triassic Rocks of Bjornoya (Bear Island). IKU, Report P-160/2/80. --, -& - - 1 9 8 3 . Organic geochemical studies of the Devonian to Triassic succession on Bjornoya and the implications for the Barents Shelf. In: BJOROY, M. et al. (eds) Advances in Organic Geochemistry 1981. Wiley, New York, 49-59. , , & WORSLEY, D. 1980. Organic Geochemistry of the Palaeozoic sequence of Bjornoya (Bear Island). IKU, Report P- 160/4/80. , VIGRAN, J. O. & RONNINGSLAND, T. M. 1979. Source Rock Evaluation of Mesozoic Shales from Svalbard. IKU, Report P-160/1/78. BLAKE, W. JR. 1960. The late Pleistocene chronology of Nordaustlandet, Spitsbergen. In: Abstracts of Papers 19th Geological Congress, Stockholm, 26-27. - - 1 9 6 1 . Radiocarbon dating of raised beaches in Nordaustlandet, Spitsbergen. In: RAASCH, O, (ed.) Geology of the Arctic. University of Toronto Press, Toronto, 133-145. - - 1 9 6 1 . Russian settlement and land rise in Nordaustlandet, Spitsbergen. Arctic, 14, 101-111. Glacial history of Svalbard and the problem of the Barents shelf ice sheet: comments. Boreas, 10, 125-128. - - 1 9 9 5 . An historical perspective of radiocarbon dating for Nordaustlandet, Svalbard; In: HACKENS, T., Kd~NIGSSON,L.-K. & POSSNERT, G. (eds) 14C methods and applications. PACT, 49. Geological Survey of Canada, 107-116. , OLSSON, I. U. & SRODON, A. 1965. A radiocarbon-dated peat deposit near Hornsund, Vestspitsbergen, and its bearing on the problem of land uplift. Norsk Polarinstitutt ,4rbok 1963, 173 180. BLANCK, E., RIESER, A. E. & MORTENSON,A. 1928. Die wissenschafflichen Ergebnisse einer bodenkundlichen Forschungsreise nach Spitzbergen in Sommer 1926. Chemie der Erde, 3, 588-698. BLEIE, J., OPPEBIEIEN,K. A. t~ NYSASTHER,E. 1982. The hydrocarbon potential of the northern Norwegian Shelf in the light of recent drilling. In: The Geological Framework and Hydrocarbon Potential of Basins in Northern Seas. Offshore Northern Seas Conference Stavager, Norway 24-27 August 1982, Article E/5. BLIECK, A. 1975. Althaspis anatirostra nov. sp., Ptrraspide du Drvonien infrrieur du Spitsberg. Compte Rendu Sommaire des Srances de la Socirt6 Gdologique de France, 3, 74-77. - - 1 9 8 2 . Les Hrtrrostracrs (Vertrbrds Agnathes) de l'horizon Vogti (Groupe de Red Bay, Ddvonien inf&ieur du Spitsberg). Cahiers Palrontologique, Editions du CNRS, Paris. - - 1 9 8 3 . Biostratigraphie du Drvonien infrrieur du Spitsberg: donnres complrmentaires sur les Hrtrrostracrs (Vertrbrrs, Agnathes) du Groupe de Red Bay. Bulletin du Musdum National d'Histoire Naturelle, Paris, 4e srrie, 5, 75-111. -& GOUJET, D. 1983. Zascinaspis laticephela nov. sp. (Agnatha, Hrtrrostraci) du Drvonien du Spitsberg. Annales de Paldontologie, Vertebrds, 69, 43-56. -& HEINTZ, N. 1979. The heterostracan faunas in the Red Bay Group (Lower Devonian) of Spitsbergen and their biostratigraphical significance: a review including new data. Bulletin Soci&6 de la Grologique de France, 7e srrie, 21, 169-181. & 1983. The cyathaspids of the Red Bay Group (Lower Devonian) of Spitsbergen. Polar Research, 1, 49-74. , GOUJET, D. & JANVIER, P. 1987. The vertebrate stratigraphy of the Lower Devonian (Red Bay Group and Wood Bay Formation) of Spitsbergen. Modern Geology, 11, 197-217. BLOMSTRAND, C. W. 1864. Geological observations during a voyage to Spitsbergen in the year 1861]. Kungliga Svenska Vetenskapsakademiens Handlingar, 4, 1-46. - - 1 8 8 0 . [Arctolite, an Arctic mineral]. Geologiska Fdreningens Stockholm Fdrhandlingar, BS, 210-216. BLOMEL, W. D., EaERLE, J. & EITEL, B. 1994. Zur jungquart~iren Vereisungsgeschichte und Landschaftsentwicklung in NW-Spitzbergen (Liefde-, Bock-und Woodfjord). Zeitschrift ffir Geomorphologie, 97, 31-42. BLt3THGEN, J. 1936. Die fauna und stratigraphie des Oberjura und der Unterkreide yon Kdnig Karl Land. Pomerania, Grummen. - - 1 9 4 1 . Tatsachen und Deutungen des Skandik (=Europ~iischen Nordmeeres). Geologie der Meere und Binnengewdsser, 5, 83-117. BLYTHE,A. E. & KLEINSPEHN,K. L. 1994. Apatite and zircon fission-track evidence for Eocene cooling of Spitsbergen and the Barents shelf. Geological Society of America, Abstracts with Programs, 26, A198. -

-

-

-

-

-

-

1

-

9

8

1

.

REFERENCES BOCKELIE, T. G. 1978. Comments on chitinozoan classification. Norsk Geolog&k Tidsskrift, 58, 301-304. - - 1 9 8 0 . Early Ordovician Chitinozoa from Spitsbergen. Palynology, 4, 1-14. -& FORTEY, R. A. 1976. An early Ordovician vertebrate. Nature, 260, 36-38. t~ YOCHELSON,E. L. 1979. Variation in a species of 'worm' from the Ordovician of Spitsbergen. Norsk Polarinstitutt Skrifter, 167, 225-237. , BRUTON, D. L. & FORTEY, R. A. 1977. Research on the Ordovician rocks of north Ny Friesland, Spitsbergen. Norsk Polarinstitutt .4rbok 1975, 214-215. BODE, H. 1929. Kohlenlagerst~itten in arktischen Gebieten. Bergbau, 42, 647-651. BODYLEVSKIY,V. I. 1926. Contributions to the natural history of Hope Island. Fossil Shells. Resultater Norske Spitzbergenekspeditioner, 1, 1-34. - - 1 9 2 9 . [Lower Dogger fauna from Mohn Bay on the east coast of Spitsbergen]. Doklady Akademii Nauk SSSR, 10, 256-258. BOGDANOV, A. 1962. Tectonic Map of Europe, Sheet 2 1.'2500000. Spitsbergen and northern Norway. (International Geological Congress Sub-Commission for the Tectonic Map of the World). Academy of Sciences, Moscow, USSR. , KHAIN, V. E., SOBOLEV, S. F., SHIPILOV,E. V., SENIN, B. V., BOGATSKY,V. I. & KOSTYUCHENKO,S. L. 1995. Tectonic Map of the Barents Sea. Terra Nova, 7, 277. BOGOLEVOV,A. K., GOLIONKO,G. B. & DERGUNOV,N. T. 1987. [Deep structure of the junction zone of the Svalbard anteclise with the central uplifts of the Barents Sea platform]. Izvestiya AN SSSR, Seriya Geologicheskaya, 1, 123-126. BOHM, J. 1899. Ueber Triasfossilien von der B~iren-lnsel. Zeitschrift der Deutschen Geologischen Gesellschaft, 51,325-326. 1903. Ober die obertriadische fauna der B/ireninsel. Vetenskaps Academiens Frrhandlingar, 37, 1-76. - - 1 9 0 4 . l]ber Nathorstites und Dawsonites aus der arkischen Trias. Zeitschrift der Deutschen Geologischen Gesellschaft, 56, 96-97. - - 1 9 1 2 . Uber Triasversteinerungen vom Bellsunde auf Spitzbergen. Arkiv fur Zoologie, 8, 1-15. BONDEVIK, S., MANGERUD,J., RONNERT, L. & SALVIGSEN,O. 1995. Postglacial sea-level history of Edgeoya and Barentsoya, eastern Svalbard. Polar Research, 14, 153180. BOSE, M. N. & MANUM, S. B. 1990. Mesozoic conifer leaves with "Sciadopitys-like" stomatal distribution. A re-evaluation based on fossils from Spitsbergen, Greenland and Baffin Island. Norsk Polarinstitutt Skrifter, 192. BOULTER, M. C. & MANUM, S. B. 1988. Palynology dates and describes the flora at the time of opening of the northern Atlantic (abstract). Palynology, 12, 232. & 1989. The Brito-Arctic igneous province flora around the Paleocene/ Eocene boundary: ODP Leg 104. In: ELDHOLM, O., THIEDE, J., TAYLOR, J. et al. (eds) Proceedings of the Ocean Drilling Program. Scientific Results, 104. College Station, Texas, 681-696. BOULTON, G. S. 1967. The development of a complex supraglacial moraine at the margin of Sorbreen, Ny Friesland, Vestspitsbergen. Journal of Glaciology, 6, 717-735. - - 1 9 6 8 . Flow tills and related deposits on some Vestspitsbergen glaciers. Journal of Glaciology, 7, 391-412. - - 1 9 7 0 . On the deposition of subglacial and melt-out tills at the margins of certian Svalbard glaciers. Journal of Glaciology, 9, 231-245. - - 1 9 7 9 a . Glacial history of the Spitsbergen archipelago and the problem of a Barents shelf ice sheet. Boreas, 8, 31-57. - - 1 9 7 9 b . A model of Weichselian glacier variation in the North Atlantic region. Boreas, 8, 373-395. & DEYNOUX, M. 1981. Sedimentation in glacial environments and the identification of tills and tillites in ancient sedimentary sequences. Precambrian Research, 15, 397-422. -& RHODES, M. 1974. Isostatic uplift and glacial history in northern Spitsbergen. Geological Magazine, 111, 481-500. --, BALDWIN, C. T., PEACOCK, J. D., MCCABE, A. M., MILLER, G., JARVIS, J., HORSEFIELD, B., WORSLEY,P., EYLES, N., CHROSTON,P., DAY, T. E., GIBBARD,P., HARE, P. E. & BRUNN, V. VON 1982. A glacio-isostatic facies model and amino acid stratigraphy for Late Quarternary events in Spitsbergen and the Arctic. Nature, 298, 437-441. BOWRING, S. A., GROTZINGER,J. P., ISACHSEN,C. E., KNOLL, A. H., PELECHATY,S. M. & KOLOSOV,P. 1993. Calibrating rates of Early Cambrian evolution. Science, 261, 1293-1298. BOYD, A. 1990. The Thyra O flora: toward an understanding of the climate and vegetation during the Early Tertiary in the high Arctic. Review of Palaeobotany and Palynology, 62, 189-203. BOYD, D. W. & NEWELL, N. D. 1977. An addition to the known geologic range of the Permian pelecypod Oriocrassatella. Contributions to Geology (University of Wyoming), 16, 55-57. BRAATHEN, A. & BERGH, S. G. 1995. Kinematics of a Tertiary delbrmation in the basement involved fold-thrust complex, western Nordenski61d Land, Svalbard: tectonic implications based on fault slip data analysis. Tectonophysics, 249, 1-29. --, -& MAHER, H. D. 1995. Structural outline of a Tertiary basement-cored uplift/inversion structure in western Spitsbergen, Svalbard: Kinematics and controlling factors. Tectonics, 14, 95-119. BRADLEY, R. S. 1985. Quaternary Paleoclimatology. Allen & Unwin, Boston. BRANNEY, M. J. & KOKELAAR, P. 1997. Giant bed from a sustained catastrophic density current flowing over topography: Acatlfin ignimbrite, Mexico. Geology, 25, 115-118. BREUER, D. & WOLF, D. 1995. Deglacial land emergence and lateral upper-mantle heterogeneity in the Svalbard Archipelago-1 First results for simple load models. Geophysical Journal International, 121, 775-778. BREUER, P. K. & ZIMMERLUND, G. 1922. l~lber Steinkohle aus Spitzbergen. BrennstChemie, 3, 98-103. -

-

BRIDEN, J. C., KENT, D. V , LAPOINTE,P. L., LIVERMORE, R. A., RoY, J. L., SEGUIN, M. K., SMITH, A. G., VAN DER Woo, R. & WATTS, D. R. 1988. Paleomagnetic constraints on the evolution of the Caledonian-Appalachian Orogen. In: HARRIS, A. L. & FEYrES, D. J. (eds) The Caledonian-Appalachian Orogen. Geological Society, London, Special Publications, 38, 35-48. BRISEID, E. & HALVORSEN, E. 1974. The primary magnetic remanence of a dolerite sill from northeast Spitsbergen. Physics of the Earth and Planetary Interiors, 9, 45 -50. BRO, Y. G., PCHELINA, T. M., PREOBRAZHENSKAYA,E. N., RONKINA, Z. Z., VOYTSEKHOVSKAYA,A. G., KRASNOVA,V. L. • MOZHAYEVA,O. V. 1991. Sedimentary cover of the Barents Sea shelf from drilling data on islands. Petroleum Geology, 25, 239-243. BROMLEY, R. G., HNKEN, N. M., ASGAARD, U., FREDREIKSEN, K. R. & HENRIKSEN, L. B. 1989. Shallow-water zoophycos assemblages, Upper Permian, Svalbard. In: Abstracts of the 28th International Geological Congress. 1. International Geological Congress, Washington, DC, 204-205. BROOKF1ELD, M. E. 1970. Eustatic changes of sea-level and orogeny in the Jurassic. Tectonophysics, 9, 347-363. BROUGH, J. & ROBERTSON, R. H. S. 1934. Geology, Geomorphology, and Glaciology. Appendix I: B. Dickson Land. C. The Sassen Valley. In: GLEN, A. R. (ed.)

-

-

481

The Oxford University Expedition to Spitsbergen 1933. Geographical Journal, 84, 117-118. BROWN, C. S., MEIER, M. F. & POST, A. 1982. Calving speed of Alaska tidewater glaciers, with application to Columbia Glacier. US Geological Survey Professional Paper 1258C. BROWN, R. N. R. 1919. Coal fields of Spitsbergen. Nature, 104, 635-637. BRUCE, W. S. 1910. The Exploration of Prince Charles Foreland, Spitsbergen, during 1906 1907, and 1909. Spottiswood, London. - - 1 9 1 1 . Scottish exploration in Prince Charles Foreland 1906 and 1907. In: Comptes Rendu. 9th Int. Geographical Congress, 3, 242-254. BR(3CKNER, H. ~: HALFAR, R. A. 1994. Evolution and age of shorelines along Woodfjorden, northern Spitsbergen. Zeitschrift ffir Geomorphologie, 97, 75-92. BRUGMANS, P. J. 1987. Spitsbergen- mining coal within the Arctic Circle. Mining Magazine, 156, 479-487. BRYANT, D. L. 1905. Beitrdge zur Petrographic Spitzbergens. Erlangen. BRYANT, I. D. 1982. Loess deposits in Lower Adventdalen, Spitsbergen. Polar Research, 2, 93-103. BRYHNI, I. 1968. Comments on 'A scheme of petrographic nomenclature'. Norsk Polarinstitutt Arbok 1966, 38-47. BUCHAN, S. H., CnALLINOR,A., HARLAND,W. B. & PARKER, J. R. 1965. The Triassic stratigraphy of Svalbard. Norsk Polarinstitutt Skrifter, 135. BUCHARDT, B. 1981. Tertiary deposits of the Norwegian-Greenland Sea region (Svalbard, Northeast- and East Greenland Sea) and their correlation to Northwest Europe. Memoirs of the Canadian Society of Petroleum Geologists, 7, 611-646. BUDA~CrSEV, L. Y. & SVESHNIKOVA, I. N. 1961. [New palaeobotanical finds in Vestspitsbergen.] Doklady Akademii Nauk SSSR, 137, 377-379. BODEL, J. 1960. Die Frostschutt-Zone Sfidost-Spitzbergens. Colloquium Geographicum 6. Ferd. Dfimm. Verlag, Bonn. - - 1 9 6 1 . Glaciological work of the German Spitsbergen Expedition 1959. In: International Association of Scientific Hydrology, Assembly of Helsinki 1960. Gentbrugge, Belgium [in German with English summary]. - - 1 9 6 8 . Die Junge Landhebung Spitsbergens in umkaers des Freeman-Sundes und der Olga-stasse. Wfirzburger Geographische Arbeiten, 22, 1-21. BUGrE, C. 1922. [Phosphorite mining in Spitsbergen]. Tidsskrift Kjemi Bergv., 10, 1-157. BUGLE, T., BAKKE, S., ELVEBAKK,G., FANAVOLL,S., GOLL, R. M., LEITH, L., MOP,K, A., MORK, M. B. E., SMELROR, M., S.~ETTEM,J. & VERDENIUS, J. 1990. Shallow Drilling Bjornoya West 1989. Main Report. IKU, Report 21.3465. , MANGERUD,G., ELVEBAKK,G., MORK, A., NILSSON,I., FANAVOLL,S. & VIGRAN, J. O. 1995. The Upper Paleozoic succession on the Finnmark Platform, Barents Sea. Norsk Geologisk Tidsskrift, 75, 3-30. BULLARD, E. C., EVERETT, J. E. & SMITH, A. G. 1965. The fit of the continents around the Atlantic. Royal Society of London, Philosophical Transactions, A258, 41-51. BUNGUM, H. 1977. Two focal-mechanism solutions for earthquakes from Iceland and Svalbard. Tectonophysics, 41, T15-T18. - - 1 9 7 8 . Reanalyzation of three focal-mechanism solutions for earthquakes from Jan Mayen, Iceland and Svalbard. Tectonophysics, 51, T15-T16. ~; KRISTOEFERSEN,Y. 1978. The seismicity of Spitsbergen: preliminary results. Norsk Polarinstitutt .4rbok 1977, 237-246. , MITCHELL,B. J. & KRISTOEFERSEN,Y. 1982. Concentrated earthquake zones in Svalbard. Tectonophysics, 82, 175-188. BURCHART, C. 1911. Bemerkungen zu einigen Arbeiten yon W. Gothan und A.G. Nathorst. Zentralblatt ffir Minerologie, Geologic und Paldontogie 1911, 442-449. BURCHER-NURMINEN, K. 1981. Petrology of chlorite-spinel marbles from NW Spitsbergen (Svalbard). Lithos, 14, 203-213. BURKE, E. A. J., ANDERSEN,T. & AMUNDSEN,H. E. F. 1991. Melting-point depressions in CO2 fluid inclusions in granulite xenoliths from NW Spitsbergen: a Ramaninactive source? (abstract). Plinius, 5, 34. BuROV, Yu. P. 1964. [Intrusive dolerites of the Spitsbergen archipelago]. In: SOKOLOV, V. N. (ed.) Conference on the Geology of Spitsbergen, Leningrad 1964: Summary of Contributions. NIIGA, Leningrad, 26-28. - - 1 9 6 5 . Peridotite inclusions and bombs in the trachybasalts of Sverre volcano in Vestspitsbergen. In: SOKOLOV, V. N. (ed.) Materialy po geologii Shpitsbergena. NIIGA, Leningrad, 260-271. & LlVSHITS,Y. Y. 1965. [Poorly differentiated dolerite intrusions in Spitsbergen]. In: SOKOLOV,V. N. (ed.) Materialy po Geologii Shpitsbergena, NIIGA, Leningrad, 246~59. -

-

-

-

482

REFERENCES

& MURASHOV, L. G. 1967. [Some results of the littlological and stratigraphical studies of the Kapp Kjeldsen Series in the Bockfjorden area]. In: SOKOLOV,V. N. (ed.) Materials' on the Stratigraphy of Spitsbergen. NIIGA, Leningrad, 63-70. & SEMEVSKIY,D. V. 1975. The main features of the tectonic structure of the Devonian graben. In: Symposium on Svalbard Geology, Oslo 2-5 June 1975, Summary of Contributions. Norsk Polarinstitutt, Oslo, 15. & 1979. The tectonic structure of the Devonian graben (Spitsbergen). Norsk Polarinstitutt Skrifter, 167, 239-248. & ZAGRUZINA, I. A. 1976. [Results of a determination of the absolute age of Cenozoic basic rocks of the northern part of the Island of Spitsbergen]. In: SOKOLOV, V. N. (ed.) Geology of Svalbard. A Collection of Articles. NIIGA, Leningrad. - - , GAVRILOV,B. P., KLUBOV,B. A., PAVLOV,A. V. & USTRITSK1Y,V. I. 1965. [New data on the Upper Permian deposits of Spitsbergen]. In: SOKOLOV,V. N. (ed.) Materialy po Geologii Shpitsbergena. NIIGA, Leningrad, 112-126. , KLtmOV, B. A., PAVLOV, A. V., GAVRILOV,B. P. & USTRITSKIY,V. I. 1964. New data on the Permian rocks of Spitsbergen. In: SOKOLOV,V. N. (ed.) Conference on the Geology of Spitsbergen, Leningrad 1964: Summary of Contributions. NIIGA, Leningrad, 6-8. , KRAS1L'SHCHIKOV,A. A., FIRSOV, L., V & KLUBOV, B. A. 1977. The age of Spitsbergen dolerites (from isotopic dating). Norsk Polarinstitutt Arbok 1975, 101-108. , SEMEVSKIY,D. V., PANOV, A. I., MOKIN, J. I. & KOLESNIK 1996. Outline of the geology of the southeastern AndrSe Land. In: KRASIL'SHCmKOV,A. A. (ed.) Soviet Geological Research in Svalbard 1962-1992. Norsk Polarinstitutt Meddelelser, 139, 35-36. BUTTERFIELD, N. J., KNOLL, A. H. & SWETT, K. 1988. Exceptional preservation of fossils in an Upper Proterozoic shale. Nature, 334, 424-427. --1994. Paleobiology of the Neoproterozoic Svanbergfjellet Formation, Spitsbergen. Fossils and Strata, 34, 1-84. CADELL, H. M. 1920. Coal-mining in Spitsbergen. Transactions of the Institution of Mining Engineers, 60, 119-142. CALAS, G., MALOD-POLVE, M., MOELO, Y. & VIAUX, C. 1977. Observations minSralogiques p&rographiques et gSochemiques sur des roches du Woodfjorden, Spitsbergen. Norsk Polarinstitutt Arbok 1975, 89-99. CALLOMON, J. H. 1959. The ammonite zones of the middle Jurassic beds of East Greenland. Geological Magazine, 96, 505 513. - - 1 9 7 6 . Jurassic ammonites from the northern North Sea. Norsk Geologisk Tidsskrift, 55, 373-386. - - 1 9 9 4 . Jurassic ammonite biochronology of Greenland and the Arctic. Bulletin of the Geological Society of Denmark, 41, 128 137. CAMERON, A. R. & GOOOARZhF. 1992. Coal and oil shales of Early Carboniferous age in northern Canada. Geological Association of Canada. Mineralogical Association of Canada, 17, AI4 A15. CAMPBELL, C. J. & ORMAASEN, E. 1987. The discovery of oil and gas in Norway: an historical synopsis. In: SPENCER, A. M. et al. (eds) Geology of the Norwegian Oil and Gas Fields'. Graham & Trotman, London, 1 37. CAMPBELL,H. J. 1994. The Triassic bivalves' Daonella and Halobia in New Zealand, New Caledonia, and Svalbard. Institute of Geological and Nuclear Sciences, Monograph 4, Lower Hutt, New Zealand. CAMPBELL, R. 1921. Recent contributions to the geology of Spitsbergen. Geological Magazine, 58, 235-236. CAREY, S. W. 1958. Continental Drift." a symposium. Geology Department, University of Tasmania, Australia. CARL,EIM-GVLLENSKOLD,V. 1900. Traveaux de l'expbdition su~doise au Spitsbergen 1898 pour la mesure d'un arc du mSridien. No. 2. [Geological notes]. Kungliga Svenska Vetenskapsakademiens O'fvers. Arg., 56, 887-900. CARLSSON, P., JOHANSSON,A. & GEE, D. G. 1995. Geochemistry of the Paleoproterozoic Bangenhuk granitoids, Ny Friesland, Svalbard. Geologiska FSreningens Stockholm FSrhandlingar, 117, 57- 120. CATXLE, H. & T.OMSON, J. F. 1993. The Arctic response to CO2-induced warming in a coupled atmosphere-ocean general circulation model. In: PELTIER, W. R. (ed.) Ice in the Climate System, Springer-Verlag, Berlin, 579 596. CHALLINOR,A. 1967. The structure of Broggerhalvoya, Spitsbergen. Geological Magazine, 104, 322-336. - - 1 9 7 9 . Spherical harmonic deformation. Journal of Petroleum Geology, 1, 75-102. CHALONEm W. G. 1958. A Carboniferous Selaginellites with Denosporites microspores. Palaeontology, 1, 245-253. CHAN, W. W. & MITCHELL, B. J. 1982. Synthetic seismogram and surface wave constraints on crustal models of Spitsbergen. Tectonophysics, 89, 51 76. & 1985a. Surface wave dispersion, crustal structure, and sediment thickness variations across the Barents shelf. Geophysical Journal of the Royal Astronomical Society 80, 329-344. -& 1985b. Intraplate earthquakes in northern Svalbard. Tectonophysics, 114, 181 191. CHAUVET, A. & SI~RANNE,M. 1989. Microtectonic evidence of Devonian extensional westward shearing in southwest Norway. In: GAYER, R. A. (ed.) The Caledonide Geology of Scandinavia. Graham & Trotman, London, 245-254.. CHENG, A., CRADDOCK, C. & ZHu, G. 1989. Kyanite in upper Proterozoic quartzite near Veslebukta, Wedel Jarlsberg Land, western Spitsbergen. Polar Research, 7, 147-148. CHERKIS, N. Z., MAX, M. D., MIDTHASSEL,A., CRANE, K., SUNDVOR,E. & VOGT, P. R. 1992. Deep ice scour and mass-wasting features on the northern Svalbard insular shelf and slope. In: Proceeding of the International ConJerence on Arctic Margins (ICAM), Anchorage, Alaska, September 1992, 333-335. CHERNYSHEV, T. 1885. Der Permisehe Kalkstein im Gouvernement Kostroma. Verhandlungen der Russisch-Kaiserlichen Mineralogischen Gesellschaft zu St. Petersburg, Series 2, 20.

-

-

-

-

-

-

-

-

,

-

-

&

- - 1 9 0 2 . Die obercarbonischen Brachyopoden des Ural und des Timan. Mdmoire du Comit~ G~ologique. Saint P(tersburg, 16, 1-749. CIqLEBOWSKI, R. & WIERZBOWSKI,A. 1983. Pyroclastic material from the Upper Triassic deposits of Sassenfjorden, Spitsbergen. Polar Research, 1, 75-82. CHOROWlCZ, J. 1992. Gravity-induced detachment of Devonian basin sediments in northern Svalbard. In: DALLMANN,W. K., ANDRESEN, A. & KRILL, A. (eds) PostCaledonian Tectonic Evolution of Svalbard. Norsk Geologisk Tidsskrift, 72, 21-26. CHRISTIANSSON, H. 1961. The Russian settlement at Russekeila and land rise in Vestspitsbergen. Arctic, 14, 112-118. CHRISTIE, R. L. 1979. The Franklinian Geosyncline in the Canadian Arctic and its relationship to Svalbard. Norsk Polarinstitutt Skrifter, 167, 263-314. CHRISTIE-BLICK,N. & BIDDLE, K. T. 1985. Deformation and basin formation along strike-slip faults. In: BIDDLE, K. T. & CHRISTIE-BLICK, N. (eds) Strike-slip Deformation, Basin Formation and Sedimentation. Special Publications, Society of Economic Paleontologists and Mineralogists, 37, 1-34. CHUMAKOV, N. M. 1968. [On the character of the Late Pre-Cambrian glaciation in Spitsbergen]. Doklady Akademii Nauk SSSR, 180, 1446-1449. - - 1 9 7 1 . [Late Precambrian glaciation of Europe and related problems]. Doklady Akademii Nauk SSSR, 198, 419 422. - - 1 9 7 1 . The Vendian glaciation of Europe and the North Atlantic. Reports of the Academy of Sciences of the Soviet Union, 198, 000-000. - - 1 9 7 8 . [Precambrian tillites and tilloids]. Nauka, Moscow. - - 1 9 8 1 . Late Precambrian tilloids of the Rybachiy Peninsula, USSR. In: HAMBREY, M. J. & HARLAND,W. B. (eds) Earth ~ Pre-Pleistocene Glacial Record. Cambridge University Press, Cambridge, 602-605. & SEMIKHATOV,M. A. 1981. Riphean and Vendian of the USSR. Precambrian Research, 15, 229~53. CHVDENIUS, K. 1865. [The Swedish expedition in 1861 under the leadership of Otto Torrell]. Norstedt & S6ner, Stockholm. CIPPITELLJ, G. 1990. A Visean-Namurian tectonic event in the western Barents Sea Arctic North-Atlantic. Memorie della Societd Geologica Italiana, 44, 49-58. CLARKE, G. K. C., COLLINS,S. G. & THOMPSON,D. E. 1984. Flow, thermal structure and subglacial conditions of a surge-type glacier. Canadian Journal of Earth Sciences, 21,232-240. CLOUD, P. E. 1955. Physical limits of glauconite formation. Bulletin of the American Association of Petroleum Geologists, 39, 484-492. COFFIELI), D. Q. 1993. Evidence for wrenching during mid-Permian extension in central East Greenland. In: VORREN, T. O. et al. (eds) Arctic Geology and Petroleum Potential. NPF Special Publications, 2, Elsevier, 89-93. COLBERX, E. H. 1964. Dinosaurs of the Arctic: new find extends Cretaceous tropics. Natural History, 73, 20-23. CO~RADh L. A. 1951. [Ballcoke from Longyear coal]. Teknisk Ukeblad, 98, 253~61. CONWAV, M. 1906. No Mans Land. A history of Spitsbergen from its discovery in 1596 to the beginning of the scientific exploration. Cambridge University Press. COOPER, R. A. & FORTEV, R. A. 1982. The Ordovician graptolites of Spitsbergen. Bulletin of the British Museum (Natural History), Geology, 36, 157-302. & LINDHOLM, K. 1990. A precise worldwide correlation of early Ordovician graptolite sequences. Geological Magazine, 127, 497 525. COPE, J. C. W. 1994. A latest Cretaceous hot spot and the southeasterly tilt of Britain. Journal of the Geological Society, London, 151, 905-908. CORBEL, J. 1953. Probldmes de morphologie pbriglaciaire au Spitzberg. Revue Gdographie, 28, 262 268. 1965. SoulSvement isostatique et englacement ancien (Spitzberg et Met de Barentz. In: BODEL, J. & WIRTHMANN, A. (eds) Vortrdge des Fridtjof-NansenGeddchtnis-Symposions fiber Spitzbergen. F. Steiner Verlag, 59 67. CSSTER, F. 1925. Quaternary Geology of the region around Kjellstr6m Valley. Results of the Swedish expedition to Spitszbergen in 1924. Geografiske Annaler, Stockholm. COWIE, J. H. 1974. The Cambrian of Spitsbergen and Scotland. In: HOLLAr~D,C. H. (ed.) Cambrian of the British Isles, Norden and Spitsbergen. Lower Paleozoic Rocks of the World, 2, London, Wiley, 123-155. 1986. Guidelines for boundary stratotypes. Episodes, 9, 78 82. -& HARLAND, W. B. 1989. Chronology. In: COWIE, J. W. & BRASIER,M. D. The Precambrian-Cambrian Boundary. Oxford University Press, Oxford, 186-198. , ZIEGLER,W., BOUCOT,A. J., BASSETT,M. G. & REMANE, J. 1986. Guidelines and statutes of International Commission of Stratigraphy (ICS). Courier Forschungsinstitut. Seckenberg, 83, 1-14. Cox, C. B. & SMIV., D. G. 1973. A review of the Triassic vertebrate faunas of Svalbard. Geological Magazine, 110, 405-418. CRADDOCK, C., HAUSER,E. C., MAHER, H. D. JR. & ZHU, C. Q. 1984. Caledonian and Tertiary structures in west Spitsbergen. In: Abstracts of the 27th International Geological Congress, Moscow, 3, 168. , SuN, A. Y. & Quo-QIANG, Z. 1985. Tectonic evolution of the West Spitsbergen fold belt. Tectonophysics, 114, 193-211. CRAIG, R. M. 1916. Outline of the geology of Prince Charles Foreland, Spitsbergen. Transactions of the Edinburgh Geological Soc&ty, 10, 276-288. CRAME, J. A. 1986. Late Mesozoic bipolar bivalve faunas. Geological Magazine, 123, 611 618. - - 1 9 9 2 . Evolutionary History of the Polar Regions. Historical Biology, 6, 37-60. - - 1 9 9 3 . Bipolar molluscs and their evolutionary implications. Journal of Biogeography, 20, 145 161. CRAMER, C. 1868. Fossile HSlzer von Green Harbour. In: HEER, O. (ed.) Die Fossile Flora der Polarldnder enthaltend die in NordgrSnland, auf der Melville Insel, in Banksland, am Mackenzie, in Island und in Spitzbergen entdeckten fossilen Pflanzen, 1. Zurich, 175 180. CRANE, K. & SOLHEM,A. 1995. Seafloor Atlas of the Northern Norwegia~Greenland Sea. Norsk Polarinstitutt, Oslo. -

-

-

-

REFERENCES --,

ELDHOLM,O., MYHRE, A. M. & SUNDVOR,E. 1982. Thermal implications for the evolution of the Spitsbergen Transform Fault (structure of the Arctic). Tectonophysics, 89, 1-32. - - , SUNDVOR,E., FOUCHER,J.-P., HOBART,M., MYHRE, A. M. c~rLEDOUARAN,S. 1988. Thermal evolution of the western Svalbard margin. Marine Geophysical Researches, 9 , 165 194. --, VOGT, P., SUNDVOR, E., DEMOUSTIER, C. & Doss, H. 1990. SeaMARCII and associated geophysical investigation of the Knipovich Ridge, Molloy Ridge/ Fracture Zone, and Barents/Spitsbergen continental margin. Part II: volcanic/ tectonic structure (abstract). EOS (Transactions of the American Geophysical Union), 71, 622. CROOT, D. G. 1975. The morphology and evolution of an esker in Spitsbergen. Norsk Polarinstitutt Arbok 1973, 237-239. CROWELL, J. C. 1964. Climatic significance of sedimentary deposits containing dispersed megaclasts. In: NAIRN, A. E. M. (ed.) Problems in Palaeoclimatology. Interscience, New York, 296. CROXTON, C. R. & PICKTON,C. A. G. 1976. The Van Mijenfjorden Group (Tertiary) of South-West Nordenski61d Land, Spitsbergen. ln: HARLAND, W. B. et al. (eds) Some Coal-bearing Strata in Svalbard. Norsk Polarinstitutt Skrifter, 164, 29 46. CUTBILL, J. L. 1968. Carboniferous and Permian stratigraphy of Ny Friesland, Spitsbergen. Norsk Polarinstitutt Arbok 1966, 12-24. & CHALLINOR, A. 1965. Revision of the stratigraphical scheme for the Carboniferous and Permian rocks of Spitsbergen and Bjornoya. Geological Magazine, 102, 418-439. - & FORBES, C. L. 1967. Graphical aids for the description and analysis of variation in fusuline foraminifera. Palaeontology, 10, 322-337. , HENDERSON, W. G. & WRIGHT, N. J. R. 1976. The Billefjorden Group (Early Carboniferous) of Central Spitsbergen. In: HARLAND,W. B. et al. (eds) Some coalbearing strata in Svalbard. Norsk Polarinstitutt Skrifter, 164, 57-89. CZAJKA, K. & MANECKI,M. 1994. Preliminary report on REE content in metamorphic black schists from the Precambrian Hecla Hoek succession, west Spitsbergen. [Vimsodden Supergroup]. Kwartalnik Geologiczny, 38, 617-622. CZARNIECKI, S. 1964. Occurrence of Genus Archimedes Hall in Hornsund, Vestspitsbergen. In: BIRKENMAJER,K. (ed.) Geological Results of the Polish 1957-1958,1959, 1960 Spitsbergen Expeditions, Part 3. Studia Geologica Polonica, 11, 147-153. --1966. Upper Palaeozoic deposits of the north-east coast of Hornsund (Vestspitsbergen). Bulletin de l'Acaddmie Polonaise des Sciences. SOrie des Sciences Gdologiques et G~ographiques, 14, 27-35. - - 1 9 6 9 . Sedimentary environment and stratigraphic position of the Treskelodden Beds (Vestspitsbergen). Prace Museum Ziemi, 16, 201-336. CZERNY, J., KIERES, A., MANECKI, M. & RAJCHEL, J. 1992. Geological map of the SW part of Wedel Jarlsberg Land, Spitsbergen. Scale 1 : 25,000. Institute of Geology and Mineral Deposits, University of Mining and Metallurgy, Crakow. , LIPIEN, G., MANECKI, A. & PIESTRZYNSKI, A. 1992. Geology and oremineralization of the Hecla Hoek succession (Precambrian) in front of Werenskioldbreen, South Spitsbergen. Studia Geologica Polonica, 98, 67-113. , PLVWACZ, I. & SZUBALA, L. 1992. Siderite mineralization in the Hecla Hoek succession (Precambrian) at Strypegga, South Spitsbergen. Studia Geologica Polonica, 98, 153-169. DAGIS, A. A. & KORCHINSKAYA,M. B. 1987. [First conodonts found in the Otoceras beds of Svalbard]. Trudy Akademiya Nauk SSSR, Sibirskoe otdelenie Instituta Geologii i Geofiziki, 110-113. - & 1989. [Triassic conodonts of Svalbard]. In: DAGIS, A. S. & DUBATOLOV, V. N. (eds) Verkhniy Paleozoy i Trias Sibiri [Upper Paleozoic and Triassic of

Siberia]. Trudy Akademiya Nauk SSSR, Sibirskoe otdelenie lnstituta Geologii i Geofiziki, 732, 109-121. DAOS, A. S. 1988. [The Middle-Lower Triassic boundary in Boreal and Tethyan regions and correlation of Anisian deposits]. Geologiya i Geofizika, 11, 3 4 . DALLAND, A. 1977. Erratic clasts in the lower Tertiary deposits of Svalbard - evidence of transport by winter ice. Norsk Polarinstitutt Arbok 1976, 151-166. - - 1 9 7 9 . Structural geology and petroleum potential of Nordenski61dland, Svalbard. In: Norwegian Sea Symposium (NSS/30). Norwegian Petroleum Society, 1-20. - - 1 9 8 1 . The sedimentary sequence of Andoya, northern Norway-depositional and structural history. Canadian Society of Petroleum Geologists, Memoirs, 7, 563-584. DALLMANN, W. K. 1988a. Thrust tectonics south of Van Keulenfjorden. In: DALLMANN, W. K., OHXA, Y. & ANDRESEN, A. (eds) Tertiary Tectonics of Svalbard. Norsk Polarinstitutt, Report Series, 46, 43-46. - - 1 9 8 8 b . The structure of the Berzeliustinden area: evidence for thrust wedge tectonics in the Tertiary fold-and-thrust belt of Spitsbergen. Polar Research, 6, 141-154. - - 1 9 8 9 . The nature of the Precambrian-Tertiary boundary at Rcnardodden, Bellsund, Svalbard. Polar Research, 7, 139-145. - - 1 9 9 0 . Late Paleozoic tectonics in the Hornsun~Sorkapp area: new evidence of 'Adriabukta Phase' deformation in a basement mobile zone (abstract). In: PostDevonian Tectonic Evolution of Svalbard. Symposium held at Department of Geology, University of Oslo, 15-16 November 1990, Norsk Polarinstitutt, Oslo. --(ed.) 1991. Geological map of Svalbard 1:100000. Sheet C.11.G. Kvalvfigen. Preliminary edition. Norsk Polarinstitutt (Oslo). - - 1 9 9 2 a . Introduction. In: DALLMANN, W. K., ANDRESEN, A. & KRILL, A. (eds) Post-Caledonian Tectonic Evolution of Svalbard. Norsk Geologisk Tidsskrift, 72,

iii.

- - 1 9 9 2 b . Multiphase tectonic evolution of the Sorkapp-Hornsund mobile zone (Devonian, Carboniferous, Tertiary), Svalbard. In: DALLMANN, W. K., ANDRESEN, A. & KRILL, A. (eds) Post-Caledonian Tectonic Evolution of Svalbard. Norsk Geologisk Tidsskrift, 72, 49-66. - - 1 9 9 3 a . Geological map of Svalbard 1:500 000, Sheet 1G Spitsbergen southern part. Revised, preliminary edition, offset colour print, Norsk Polarinstitutt.

483

- - 1 9 9 3 b . Notes on the stratigraphy, extent and tectonic implications of the Minkinfjellet Basin, Middle Carboniferous of central Spitsbergen. Polar Research, 12, (Research Note). -& KRASIL'SHCHIKOV,A. A. 1996. Geological Map of Svalbard. 1:50000, sheet D2OG. Bjornoya. Norsk Polarinstitutt, Temakart, no. 27. -& MAHER, H. D. JR. 1989. The Supanberget area - basement imbrication and detached foreland thrusting in the Tertiary fold-and-thrust belt, Svalbard. Polar Research, 7, 95-107. & MORK, A. (eds) 1991. Stratigraphical Dictionary for Svalbard. Norsk Polarinstitutt Rapportserie, 74 [translation from Gramberg, Krasil'shchikov & Semevskiy 1990]. - - , ANDRESEN,A., BERGH, S. G., MAHER JR., H. D. & OHTA, Y. 1993a. Tertiaryfoldand-thrust belt of Spitsbergen, Svalbard. Norsk Polarinstitutt, Meddelelser, 128. --• KRILL, A. 1992. Post Caledonian tectonic evolution of Svalbard. Proceedings of Symposium in Oslo 19-16.11.1990. Norsk Geologisk Ticlsskrift, 72. --, BIRKENMAJER,K., HJELLE, A., MORK, A., OHTA, Y., SALVIGSEN,O. & WINSNES, T. S. 1993b. Geological Map of Svalbard 1:100000 Sheet C13G Sorkapp (description). Norsk Polarinstitutt Temakart No. 17. - - , HJELLE, A. H., SALVIGSEN,O., BJORNERUD,M. G., HAUSER, E. C., MAHER, H. D. & CRADDOCK, C. 1990. Geological Map of Svalbard 1:]00 000, Sheet BllG, Van Keulenfjorden. Norsk Polarinstitut, Oslo, Temakart No. 15. --, OHTA, Y. t~r ANDRESEN, A. (eds) 1988. Tertiary Tectonics of Svalbard. Norsk Polarinstitutt. Report Series, 46. , , BIRJUKOV,A. S., KARSOUSENKO,E. P. & SIROTKIN,A. N. 1994. Geological map of Svalbard 1:I00 000. Sheet C7G Dicksonfjorden. (Digital edition). Norsk Polarinstitutt. , MIDBOE, P. S., NOrrVEDT, A. & STEEL, R. J. 1995. Lithostratigraphical nomenclature of the Tertiary rocks of Svalbard. SKS, Norway. , WINSNES, W. S. 8~; BIRKENMAJER,K. 1993. Geological map of Svalbard 1:100000, Sheet C11G Kvalvdgen. Norsk Polarinstitutt, 23. --, GJELLBERG,J. G., HARLAND, W. B., JOHANNESSEN,E., KEILLEN,n., LONOY, A., NILSSON, I. & WORSLEY, D. 1996. [Proposal of] Lithostratigraphical nomenclature of the Upper Paloezoic of Svalbard. SKS, Norway. DALLMEYER, R. D. 1989. Partial thermal resetting of 4~ mineral ages in western Spitsbergen, Svalbard: possible evidence for Tertiary metamorphism. Geological Magazine, 126, 587-593. -& TUCKER, R. D. 1991. Tectonothermal evolution of crystalline basement units in the East Greenland Caledonide foreland: 76 78~ In: Terranes in the Arctic Caledonides, Tromso, 12-16 August 1991. Terra Abstracts, 4, 14-15. , PEUCAT, J. J. & OHTA, Y. 1990. Tectonothermal evolution of contrasting metamorphic complexes in northwest Spitsbergen (Biskayerhalvoya): evidence from 4~ and Rb-Sr mineral ages. Bulletin of the Geological Society of America, 102, 653-663. , PEUCAT,J. J., HIRAJIMA,T. & OHTA, Y. 1990. Tectonothermal chronology within a blueschist-eclogite complex, west-central Spitsbergen, Svalbard: evidence from 4~ and Rb-Sr mineral ages. Lithos, 24, 291-304. , STRACHAN, R. A. & HENRIKSEN,N. 1994. 4~176 mineral age record in NE Greenland: implications for tectonic evolution of the North Atlantic Caledonides. Journal of the Geological Society, London, 151, 615-628. DALZIEL, I. W. D. 1991. Pacific margins of Laurentia and East Antarctica-Australia as a conjugate rift pair: Evidence and implications for an Eocambrian supercontinent. Geology, 19, 598-601. - - 1 9 9 7 . Neoproterozoic-Paleozoic geography and tectonics: Review, hypothesis, environmental speculation. Geological Society of America Bulletin, 109, 16-42. DAMES, W. 1895. ()ber die Ichtyopterygier der Triasformation. S. B. Preussischen Akademie der Wissenschaften Jahrg., 46, 1045. DANYUSHEVSKAYA,A. I., VOYCECHOVSKAYA,L. F., KOTOLOVA,L. F. & KRASIL'SHCHIKOV,A. A. 1970. The geochemistry of dispersed organic matter in the Precambrian deposits of Spitsbergen. Geology of Oil and Gas, 3 March 1970, 47-53. DAy, B. N. 1964. [Results of experinaental-methodical resistivity prospecting work of Vestspitsbergen in 1963]. In: SOKOLOV,V. N. (ed.) Conference on the Geology of Spitsbergen, Leningrad 1964: Summary of Contributions, NIIGA, Leningrad, 31 32. DAVIS, F. L. 1919. Spitsbergen. Geographical Journal, 53, 207-208. DAVIS, G. R. & NASSICHUK,W. W. 1991. Carboniferous and Permian history of the Sverdrup Basin, Arctic Islands. In: TRETTrN, H. P. (ed.) Geology of the Innuitian Orogen and Arctic Platform of Canada and Greenland. Geological Survey of Canada and Geological Society of America, Ottawa, 343-362. DAWES, P. R. 1976. Precambrian to Tertiary of northern Greenland. In: ESCHER,A. & WATt, W. S. (eds) Geology of Greenland. Gronlands Geologiske Undersogelse, Copenhagen, 249-303. DAWSON, J. W. 1873. Note on the relations of the supposed Carboniferous plants of Bear Island with the Paleozoic flora of North America. Geological Magazine, 43. DE BUFFRENIL, V., MAZIN, J. M. & DE RICQLES, A. 1987. Caract6res structuraux et mode de croissance du f+mur d'Omphalosaurus nisseri, ichthyosaurien de Trias moyen de Spitsberg [Structural features and growth process in a femur of the Middle Triassic ichthyosaur Omphalosaurus nisseri from Spitsbergen. Annales de Pal~ontologie, VertebrOs, 73, 195-216. DECKER, P. L., CRADDOCK, C., BJORNERUD, M. 8~ NANIA, J. C. 1986. Deformed clasts in the Hecla Hock succession, Wedel Jarlsberg Land, west Spitsbergen. Geological Society of America, Abstracts with Programs, 18, 285. DEGE, E. 1965. Der Kohlenbergbau auf Spitsbergen. Polarforschung Jahrg, 268-273. --1960. Wissenschaftliche Beobachtungen auf dem Nordostland yon Spitzbergen 1944 1945, 10 (10), Beitr/ige von Arther Baumann. Berichte des Deutschen Wetterdienstes [English Summary]. DE GEER, G. 1896. [Report of the Swedish geological expedition to Isfjorden in Spitsbergen in the summer of 1896]. Ymer, 4, 259-266.

484

REFERENCES

[New contributions to the geology of Spitsbergen]. Forhandlinger ved de Skandinaviske Naturforskeres Mote, 15, 229-231. - - 1 9 0 0 a . [On extending the arc measurement over southern and middle Spitsbergen]. Ymer, 20, 281-302. - - 1 9 0 0 b . [The glaciation of East Spitsbergen during the glacial period]. Geologiska Frreningens i Stockholm Frrhandlingar, 201, 427-436. --1901. [Traces after worms in a dolomite from Hecla Hock]. Geologiska Frreningens i Stockholm Frrhandlingar, 23, 532. - - 1 9 0 8 . [The Swedish Spitsbergen expedition in 1908]. Ymer, 28, 102-105 and 341-344. - - 1 9 0 9 . Some leading lines of dislocation in Spitzbergen. Geologiska Frreningens i Stockholm Frrhandlingar, 31, 199-208. - - 1 9 1 0 . A geological excursion to the Central Spitzbergen. In: Guide de l'excursion au Spitsberg. XI Congrrs Grologique Internationale, Stockholm, 1-23. - - 1 9 1 2 . The coal region of Central Spitzbergen. Ymer, 32, 335-380. - - 1 9 1 3 . The north coast of Spitsbergen, western part. Ymer, 33, 230-277. - - 1 9 1 9 . On the physiographical evolution of Spitsbergen. Geografiske Annaler, 1, 169-192. - - 1 9 2 0 . [On the nature of Spitsbergen in the neighbourhood of Sveagruva]. Ymer, 1919, 240-277. - - 1 9 2 3 . Description topographique de la rrgion explorre. Grologie. In: Mission Scientifique pour la mesure d'un arc de mdridien au Spitsberg entreprises en 1899-1902 sous les auspices des gouvernements suddois et russe. Miss. Surdois, 2 (9), 1-36. DE KONINCK,L. 1846. Notice sur quelques fossiles du Spitzberg. Bulletin de l'Acaddmie Royal de Belgique - Classe de Sciences, 13, 592-596. - - 1 8 5 0 / 1 8 4 9 ? Nouvelle notice sur les fossiles du Spitzberg. Bulletin de l'Acaddmie Royal de Belgique - Classe des Sciences, 16, 632-643. DE LAPPARENT,A. F. 1962. Footprints of dinosaur in the Lower Cretaceous of Vestspitsbergen, Svalbard. Norsk Polarinstitutt ~lrbok 1960, 14-21. DENGO, C. A. & ROSSLAND, K. G. 1992. Extensional tectonic history of the western Barents Sea. In: LARSEN, R. M. et al. (eds) Structural and Tectonic Modelling and its Application to Petroleum Geology, Norwegian Petroleum Society (NPF), Special Publications. Elsevier, Amsterdam, 91-107. DE NORSKEKULFELTERSPITSBERGENA/S 1916. Aktieinnbydelse [Company prospectus] (Norsk Kunngjorelsestidende No. 120) De Norske Kulfelter Spitsbergen A/S, Kristiania. DENTON, G. H. & HUGHES,T. J. (eds) 1981. The last great ice sheets, Wiley, New York. DE PAOR, D. G., BRADLEY,D. C., EISENSTADT,G. & PHILLIPS,S. M. 1989. The Eurekan Orogeny: A most unusual fold and thrust belt. Geological Society of America, Bulletin, 101, 952-967. DERRY, L. A., KETO, L. S., JACOBSEN, S. B., KNOLL, A. H. & SWE~Vr, K. 1989. Sr isotopic variations in Upper Proterozoic carbonates from Svalbard and East Greenland. Geochimica et Cosmochimica Acta, 53, 2331-2339. DETTMANN, M. E. & PLAYFORD, G. 1963. Sections of some spores from the Lower Carboniferous of Spitsbergen. Palaeontology, 5, 679-681. DEIATSCHER SEESEISCHEREI-VEREIN1900. Die Expedition des Deutschen SeefischereiVereins in das n6rdliche Eismeer vom Jahre 1899. In: VIII. Das Kohlenvorkommen. Mitt. Dtsch. SeefischVer, 16(1), 32-33. DIBNER, A. F. 1986. [Stratification of the Culm deposits of Spitsbergen by palynological evidence]. Geologija osadocnogo cechla archipelaga Shpitsbergen Leningrad," Sevmorgeologija, 34-74. DroNER, V. D. 1968. ['Ancient clays' and the relief of the Barents-Kara shelf- the evidence of the existence of an ice sheet in Pleistocene]. Problemy arktiki i antarktiki, 255, 118-122. - - 1 9 8 2 . Precambrian and Palaeozoic of Spitsbergen (from new data in the literature), ln: Collected Information of the Institute of Arctic Geology', 27, 21-29. Institute of Arctic Geology, Leningrad, 21-29 [in Russian]. -& KRYLOVA, N. M. 1963. [Stratigraphic position and material composition of coal measures in Franz Josef Land. Soviet Geology]. Trans. International Geology Review, 7, 1030-1038. DILLNER, G. 1913. [The coal and coke problem as seen from the point of view of the Swedish iron industry]. Jernkontor. Ann. 1913, 585-689. DIMIKOWSKI, E. 1884. Ueber Permo-Carbon-Schwdimme yon Spitzbergen. Kungliga Svenska Vetenskapsakademiens Handlinge, 21. Uppsala & Stockholm. DINELEY, D. L. 1953a. Quaternary faunas in the St. Jonsfjord-Eidembukta region, Vestspitsbergen. Norsk Geologisk Tidsskrift, 34, 1-14. - - 1 9 5 3 b . Raised features on the west coast of Vestspitsbergen. Geographical Journal, 119, 505-508. - - 1 9 5 3 c . Notes on the genus Corvaspis. Proceedings of the Royal Society of Edinburgh, 65, 166-181. - - 1 9 5 4 . Quaternary faunas in the St Jonsfjord-Eidembukta region, Vestspitsbergen. Norsk Geologiske Tidsskrift, 34, 1-14. - - 1 9 5 5 . Some Devonian fish remains from north central Vestspitsbergen. Geological Magazine, 92, 255-260. - - t 9 5 8 . A review of the Carboniferous and Permian rocks of the west coast of Vestspitsbergen. Norsk Geologisk Tidsskrift, 38 197-217. - - - 1 9 6 0 . The Old Red Sandstone of Eastern Ekmanfjorden, Vestspitsbergen. Geological Magazine, 97, 18-32. - & ALLEN, J. R. L. 1960. Deposition of the Old Red Sandstone. Geological Magazine, 97, 509-510. -& GARRETr, P. A. 1959. Whale remains in glacier ice. Nature, 183, 272. DITCHHELD, P. W. 1997. High northern palaeolatitude. Jurassic-Cretaceous palaeotemperature variation: new data from Kong Karls Land, Svalbard. Palaeogeography, Palaeoclimatology, Palaeoecology, 130, 163-175. & STALEr, S. In press. Early Cretaceous palaeotemperatures from the Carolinefjellet Formation of Spitsbergen. Geological Magazine. --1899.

DrrTMER, R. 1901. Das Nord-Polarmeer. Nach Tagebfichern und Aufnahmen w(ihrend der Reise mit Sr. Maj. Schiff "Olga", Hannover and Leipzig. DONNER, J. J. & WEST, R. G. 1957. The Quaternary geology of Brageneset, Nordaustlandet, Spitsbergen. Norsk Polarinstitutt, Skrifter, 109. DORE, A. G. & JENSEN, L. N. 1996. Sediment flux from a fjord during glacial periods, Isfjorden, Spitsbergen. Global and Planetary Change, 12, 415-436. DOVER, J. H. 1990. Problems of terrane terminology - causes and effects. Geology, 18, 487-488. DOWDESWELL,E. K. 1988a. The Cenozoic stratigraphy and tectonic development of the Barents Shelf. In: HARLAYD, W. B. & DOWDESWELL, E. K. (eds) Geological Evolution of the Barents Shelf Region. Graham & Trotman, London, 131-155.. - - 1 9 8 8 b . Cenozoic panarctic tectonic events. In: HARLA~, W. B. & DOWDESWELL, E. K. (eds) Geological Evolution of the Barents Shelf Region. Graham & Trotman, London, 33-46. DOWDESWELL, J. A. 1986. Drainage-basin characteristics of Nordaustlandet ice caps, Svalbard. Journal of Glaciology, 31, 31-38. - - 1 9 8 9 . On the nature of Svalbard icebergs. Journal of Glaciology, 35, 224-234. - - 1 9 9 5 a . Deep Pleistocene iceberg plowmarks on Yermak Plateau: sidescan and 3.5 KHz evidence for thick calving ice fronts and a possible marine ice sheet in the Arctic ocean [comment]. Geology, 23, 476-477. --1995b. Glaciers in the High Arctic and recent environmental change. Philosophical Transactions of the Royal Society, A352, 321-334. -& BAMBER, J. L. 1995. On the glaciology of Edgeoya and Barentsoya, Svalbard. Polar Research, 14, 105-122. -& COLLIN,R. L. 1990. Fast-flowing outlet glaciers on Svalbard ice caps. Geology, 18, 778-781. -& DOWDESWELL, E. K. 1989. Debris in icebergs and rates of glaci-marine sedimentation: observations and a simple model. Journal of Geology, 97, 221-231. -& DREWRY, D. J. 1985. Place names on the Nordaustlandet ice caps, Svalbard. Polar Record, 22, 519-523. - & - - 1 9 8 9 . The dynamics of Austfonna, Nordaustlandent, Svalbard: surface velocities, mass balance and subglacial meltwater. Annals of Glaciology, 12, 37-45. - & FORSBERG, C. F. 1992. The size and frequency of icebergs and bergy bits from tidewater glaciers in Kongsfjorden, north-west Spitsbergen. Polar Research, 11, 81-91. , DREWRY, D. J., COOPER, A. P. R., GORMAN, M. R., LIESTOL,O. • ORHEIM, O. 1986. Digital mapping of the Nordaustlandet ice caps from airborne geophysical investigations. Annals of Glaciology, 8, 51-58. --, - - , LIESTOL,O. &; ORHEIM, O. 1984a. Airborne Radio echo sounding of subpolar glaciers in Spitsbergen. Norsk Polarinstitutt Skrifter, 182, 41. , , & 1984b. Radio echo-sounding of Spitsbergen glaciers: problems in the interpretation of layer and bottom returns. Journal of Glaciology, 30, 16-21. --, -& SIMOES, J. C. 1990. Comment on: "6000-year climate records in an ice core from the Hoghetta ice dome in northern Spitsbergen". Journal of Glaciology, 36, 353-356. , HAMaREV, M. J. & Wu, R. T. 1985. A comparison of clast fabric and shape in Late Precambrian and modern glacigenic sediments. Journal of Sedimentary Petrology, 55, 691-704. , HAMILTON,G. S. & HAGEN, J. O. 1991. The duration of the active phase on surge-type glaciers: contrasts between Svalbard and other regions. Journal of Glaciology, 37, 388-400. , HODGKINS,R., NUTTALL, A. M., HAGEN, J. O. & HAMILTON,G. S. 1995. Mass balance change as a control on the frequency and occurrence of glacier surges in Svalbard, Norwegian High Arctic. Geophysical Research Letters, 22, 2909-2912. & 10 OTHERS 1997. The mass balance of circum Arctic glaciers and recent climatic change. Quarternary Research, 48, 1 14. DOWLING, L. M. 1988. Cenozoic evolution of the western margin of the Barents Shelf. In: HARLAND, W. B. & DOWDESWELL,E. K. Geological Evolution of the Barents Shelf Region. Graham & Trotman, London, 157-169. DOYLE, P. 1986. The belemnites of Svalbard and the "Arctic" zoogeographic province of the Boreal Realm in the Early Jurassic-Lower Cretaceous. In: Abstracts of

Annual Conference of Palaeontological Association, Leicester 18-21 December 1986. Department of Geology, Leicester University, 12-13. - - 1 9 8 7 . Systematic status of Pseudohibolites Bliithgen 1936 (Belemnitida, Coleoidea) from Kong Karls Land, Svalbard (abstract). Geological Magazine 124, 165-166. & KELLY, S. R. A. 1988. The Jurassic and Cretaceous belemnites of Kong Karls Land, Svalbard (abstract). Norsk Polarinstitutt Skrifter, 189, 1-77. DRASCHE, R. V. 1874. Petrographisch-geologische Beobachtungen an der West-Kfiste Spitzbergens. Tschermaks Mineralogische und Petrographische Mitteilungen, 3, 181-198 and 261-268. DREIMANIS,A. 1979. The problems of waterlain tills. In: SCHLUCTER,C. (ed.) Moraines and Varves. A. A. Balkema, Rotterdam, 167-177. DRINKWATER, N . J., PICKERING, K . T . & SIEDLECKA, A . 1996. Deep-water faultcontrolled sedimentation, Arctic Norway and Russia: response to Late Proterozoic rifting and the opening of the Iapetus Ocean. Journal of the Geological Society, London, 153, 427-436. DU TOIT, A. L. 1937. Our Wandering Continents, Oliver & Boyd, Edinburgh. DUBOIS, A. 1911. La rrgion du Mont Lusitania au Spitzberg. Bulletin Neuchdtel de Gdographie, 21, 53-77. DUK, G. G. & ZAPOL'NOV,A. K. 1987. [Geosynclinal complexes of the Late Riphean]. Izvestiya AN SSSR, Seriya Geologicheskaya, 8, 138-140. DUNER, N. & NORDENSKIt3LD,A. E. 1867. [the Swedish expedition to Spitsbergen in the year 1864 made under the leadership of A.E. Nordenskirld on board the "'Axel Thordsen"], Stockholm. DUNIKOWSKI,E. VON 1884. Ueber Permo-Carbon-Schwdme von Spitzbergen. Kungliga Svenska Vetenskapsakademiens Handlinger, 21. Uppsala & Stockholm.

REFERENCES DUROCHER, M . J . 1840-1850. Observations g6ologiques sur la Scandinavie et le Spitzberg. In: GAIMARD, P. (ed.) Voyages en Scandinavie, en Lapponie, au Spitzberg et aux Fer6e, pendant les ann~es 1838, 1839 et 1840 sur la corvette La Recherche, 29e, 469-478. Paris. -c. 1850 (?1839). Gkologie, Mindralogie, M~tallurgie et Chimie (Voyages en Scandinavie, en Laponie, au Spitzberg et aux Fer6e, pendant les ann+es 1838 1939 et 1840), Arther Bertrand, Paris. (Paul Gaimard, President de la Commission Scientifique du Nord). DUTRO, J. T., JR. 8L SALDUKAS, R. B. 1973. Permian palaeogeography of the Arctic. Journal of Research, United States Geological Survey, 1, 501-507. DUTUIT, J. M. 8~ HEYLEN, D. 1975. Presence de cellules d'evidement dans les os de l'arri6re-crane de deux stegocephales triassiques [Presence of cellular apertures in the bones in the back of the skull of two Triassic stegocephelians]. CNRS, Colloques Internationals, 218, 331-336. DYPVIK, H. 1978. Origin of carbonate in marine shales of the Janusfjellet Formation, Svalbard. Norsk Polarinstitutt Arbok 1977, 101-110. 1979. Major and minor element chemistry of Triassic black shales near a dolerite intrusion at Sassenfjorden, Spitsbergen. Chemical Geology, 25, 53-65. - - q 9 8 0 a . Geochemical studies of sedimentary constituents in Mesozoic shales. Norsk Polarinstitutt Skrifter, 172, 135-143. - - 1 9 8 0 b . The sedimentology of the Janusfjellet Formation, central Spitsbergen (Sassenfjorden and Agardhfjellet areas). Norsk Polarinstitutt Skrifter, 172, 97 134. 1985. Jurassic and Cretaceous black shales of the Janusfjellet Formation, Svalbard, Norway. Sedimentary Geology, 41, 235 248, 1992a. Sedimentary rhythms in the Jurassic and Cretaceous of Svalbard. Geological Magazine, 129, 93 99. 1992b. Jurassic-Cretaceous depositional history and paleogeography of the North Greenland-Svalbard region (abstract). In: International Conference on Arctic margins, 2-4 September 1992, 15. ICAM, Anchorage, Alaska. - - - & BUE, B. 1984. The U, Th and K distribution in black shales of the Janusfjellet Formation, Svalbard, Norway. Chemical Geology, 42, 287-296. -& NAGV, J. 1979. Early Tertiary bentonites from Svalbard. Geological Magazine, 116, 457-468. --, GUDLAUGSSON, S. T., TSIKALAS, F., ATTREP, JR. M., FERRELL, J., KRINSLEY, D. H., MORK, A., FALEIDE, J. I. & NAGY, J. 1996. Mjolnir Structure: an impact Crater in the Barents Sea. Geology, 24, 779-782. --, HVOSLEF, S., BJAERKE, T. & FINNERUD, E. 1985. The Wilhelmoya Formation (Upper Triassic-Lower Jurassic) at Bohemanflya, Spitsbergen. Polar Research, 3, 155-166. --, NAGY, J., EIKELAND, T. A., BACKER-OWE, K., ANDRESEN, A., HAREMO, P., BJtERKE, T., JOHANSEN, H. & ELVERHOI, A. 1991a. The Janusfjellet Subgroup (Bathonian to Hauterivian) on central Spitsbergen: a revised lithostratigraphy. Polar Research, 9, 21-43. , , , & JOHANSEN, H. 1991b. Depositional conditions of the Bathonian to Hauterivian Janusfjellet Subgroup, Spitsbergen. Sedimentary Geology, 72, 55-78. , NAGY, J. & KR~NSLEY,D. H. 1992. Origin of the Myklegardfjellet Bed, a basal Cretaceous marker on Spitsbergen. Polar Research, 11, 21 33. EDWARDS, M. B. 1975. Gravel fraction on the Spitsbergen Bank, NW Barents Shelf. Norges Geologiske Undersokelse Bulletin, 316, 205-217. 1975. Preliminary Report on Upper Palaeozoic and Mesozoic Sandstones of Svalbard. A reconnaissance. IKU, Trondheim, Publication 87. 1976a. Depositional environments in Lower Cretaceous regressive sediments Kikutodden, Sorkapp Land, Svalbard. Norsk Polarinstitutt Arbok 1974, 35-51. 1976b. Growth faults in Upper Triassic deltaic sediments, Svalbard. Bulletin of the American Association of Petroleum Geologists, 60, 341-355. 1976c. Sedimentology of Late Precambrian Sveanor and Kapp Sparre Formations at Aldousbreen, Wahlenbergfjorden, Nordaustlandet. Norsk Polarinstitutt Arbok 1974, 51-62. - - 1 9 7 8 . A regional survey of composition, provenance and diagenesis of sandstones in the Lower Cretaceous Helvetiafjellet Formation, Svalbard. Norsk Polarinstitutt Arbok 1977, 343-345. 1979. Sandstone in Lower Cretaceous Helvetiafjellet Formation, Svalbard: bearing on reservoir potential of Barents Shelf. Bulletin of the American Association of Petroleum Geologists, 63, 2193-2203. - - 1 9 7 9 . Late Precambrian glacial loessites from North Norway and Svalbard. Journal of Sedimentary Petrology, 49, 85-92. - - 1 9 8 1 . Diagenetic and sedimentological explanation for high seismic velocity and low porosity in Mesozoic-Tertiary sediments, Svalbard region: discussion. Bulletin of the American Association of Petroleum Geologists, 65, 2437-2439. - - 1 9 8 4 . Sedimentology of the Upper Proterozoic glacial record, Vestertana Group, Finnmark, North Norway. Norges Geologiske Undersokelse, Bulletin, 394, 1-76. -& TAYLOR, P. N. 1976. A Rb-Sr age for granite-gneiss clasts from the late Precambrian Sveanor Formation, Central Nordaustlandet. Norsk Polarinstitutt Arbok 1974, 255-258. , BJAERKE,T., NAOY, J., W~NSNES,T. & WORSLEY,D. 1979. Mesozoic stratigraphy of Eastern Svalbard: a discussion. Geological Magazine, 116, 49-54. --, EDWARDS, R. & COLBERT, E. 1978. Carnosaurian footprints in the Lower Cretaceous of eastern Spitsbergen. Journal of Paleontology, 52, 940-941. EIKEN, O. 1983. Seismic sections of Svalbard Lines: 1 2, 3 4A-J, 5A-B, 6 each on one sheet Bergen: University of Bergen. - - 1 9 8 5 . Seismic mapping of the post-Caledonian strata in Svalbard. Polar Research, 3, 167-176. - - 1 9 9 3 . An outline of the northwestern Svalbard continental margin. In: VORRrN, T. O. et al. (eds) Arctic Geology and Petroleum Potential, NPF Special Publication, 2. Elsevier, 619-629.

485

(ed.) 1994. Seismic atlas of Western Svalbard, a selection of regional seismic transects. Norsk Polarinstitutt Meddelelser, 130. - - & AUSTEGARD,A. 1987. The Tertiary orogenic belt of West-Spitsbergen: seismic expressions of the offshore sedimentary basins. Norsk Geologisk Tidsskrift, 67, 383-394. - & 1989. The Tertiary orogenic belt of West Spitsbergen: seismic expressions of the offshore sedimentary basins. A reply. Norsk Geologisk Tidsskrift, 69, 137-139. EINARSSON, P. 1986. Seismicity along the eastern margin of the North Atlantic Plate. In: VOGT, P. R. & TUCnOLKE, B. E. (eds) The Western North Atlantic Region. Geology of North America, Geological Society of America, 99-116. ELBO, J.G. 1952. The War in Svalbard 1939-45. Polar Record, 6, 484-495. EL-KAMMAR, A. M. & NYSa~THER, E. 1980. Petrology and mineralogy of phosphatic sediments, Svalbard. Norsk Polarinstitutt Skrifter, 172, 169-181. ELDHOLM, O. & SUNDVOR, E. 1979. Geological events during the early formation of a passive margin. Tectonophysics, 59, 233 237. , FALmDE, J. I. & MYHRE, A. M. 1987. Continent-ocean transition at the western Barents Sea/Svalbard continental margin. Geology, 15, 1118-1122. , MYHRE, A. M., FALEIDE, J. I., GUDLAUGSSON, S. T. & SKOGSEID, J. 1988. Structure and evolution of passive continental margins and adjacent areas: research within the framework of the International Lithosphere Programme 1985-1987. In: KRISTOFFERSEN,Y. (ed.) Progress in Studies of the Lithosphere in Norway. Norges geologiske Undersokelse, Special Publications, 3, 29-38. , SKOGSEID,J., SUNDVOR, E. & MYHRE, A. M. 1990. The Norwegian-Greenland Sea. ln: GRANTZ,A., JOHNSON,L. & SWEENEY,J. F. (eds) The Arctic Ocean Region, The Geology of North America, L. Geological Society of America, 351-364. , SUNDVOR, E. & CRANE, K. 1984. Sonobuoy measurements during the "Ymer" expedition. Norsk Polarinstitutt Skrifter, 180, 17-23. , MYRE, A. M. & FALHDE, J. I. 1984. Cenozoic evolution of the continental margin off Norway and western Svalbard. In: SVENCER, A. M. (ed.) Petroleum Geology of the North European Margin. Norwegian Petroleum Society/Graham & Trotman, London, 3-18. ELTON, C. S. 1922. Geological notes from the Oxford expedition to Spitsbergen. Geographical Journal, 60, 424-426. - - 1 9 2 7 . The nature and origin of soil polygons in Spitsbergen. Quarterly Journal of the Geological Society of London, 83, 163-194. - & BADEN-POWeLL,D. F. W. 1931. On a collection of raised beach fossils from Spitsbergen. Geological Magazine, 68, 385-405. ELVEBAKK,A. & PRESTRUD, P. 1996. A Catalogue of Svalbard plants, fungi, algae and cyanobacteria. Norsk Polarinstitutt, Skrifter, 198, 1-395. ELVERHOI, A. 1981. Diagenetic and sedimentologic explanation for high seismic velocity and low porosity in Mesozoic-Tertiary sediments, Svalbard region: reply. Bulletin of the American Association of Petroleum Geologists, 65, 2437-2440. - & BJ~IRLYKKE,K. 1978. Sandstone diagenesis - Mesozoic rocks from southern Spitsbergen. Norsk Polarinstitutt Arbok 1977, 145-157. - & Gr~NLIE, G. 1981. Diagenetic and sedimentologic explanation for high seismic velocity and low porosity in Mesozoic-Tertiary sediments, Svalbard region. Bulletin of the American Association of Petroleum Geologists, 65, 145-153. -& KR|STOEEERSEN, Y. 1978. Glacial deposits south-east of Bjornoya, northwestern part of the Barents Sea. Norsk Polarinstitutt ~lrbok 1977, 209-215. -& LAUmTZEN, O. 1984. Bedrock geology of the northern Barents Sea (west of 35 degrees) as inferred from the overlying Quaternary deposits. Norsk Polarinstitutt Skrifter, 180, 5-16. - & SOLHEIM,A. 1983. The Barents Sea ice sheet - a sedimentological discussion. Polar Research, 1, 23-42. -& 1987. Shallow geology and geophysics of the Barents Sea - with special reference to the existence and detection of submarine permafrost. Norsk Polarinstitute Rapport, 37. - - , LmSTOL, O. & NAGY, J. 1980. Glacial erosion, sedimentation and microfauna in the inner part of Kongsfjorden, Spitsbergen. Norsk Polarinstitutt Skrifter, 172, 33-60. --, LONNE, O. & SELAND, R. 1983. Glaciomarine sedimentation in a modern fjord environment, Spitsbergen. Polar Research, 1, 127-149. - - , PEmMAN, S. L., SOLHEXM,A. & LARSSEN,B. B. 1989. Glaciomarine sedimentation in epicontinental seas exemplified by the northern Barents Sea. Marine Geology, 85, 225-250. --, FJELDSKAAR,W., SOLHEIM, A., NYLAND-BERG, M. & RUSSWURM, L. 1993. The Barents Sea Ice Sheet - a model of its growth and decay during the last ice maximum. Quaternary Science Reviews, 12, 863 873. EMBRY, A. F. 1989. Correlation of Upper Paleozoic and Mesozoic sequence between Svalbard, Canadian Archipelago, and northern Alaska. In: COLLtNSON,J. D. (ed.) Correlation in Hydrocarbon Exploration. Graham & Trotman, London, 89-98. ESCHER, A. & WATT, W. S. 1976. Geology of Greenland. Geological Survey of Greenland, Copenhagen. ESCrtER, E. F. 1965. Geological sketch of Svalbard Islands (Spitsbergen). Geologie en M~inbouw, 44, 285-294. ETHERIDGE, R. 1878. Palaeontology of the Coasts of the Arctic Lands visited by the late British Expedition under Captain Sir George Nares. Quarterly Journal of the Geological Society of London, 34, 568-639. ETHIN~TON, R. L. & CLARK, D. L. 1982. Lower and Middle Ordovician conodonts from the Ibex area, western Country, Utah. Geology Studies, Brigham Young University, 28. EVANS, D. H. & KING, A. H. 1990. The affinities of early oncocerid nautiloids from the Lower Ordovician of Spitsbergen and Sweden. PaIaeontology, 33, 623-630. EYLES, N. & YOUNG, G. M. 1994. Geodynamic controls on glaciation in Earth history. In: DEwqoux, M. et al. (eds) Earth's Glacial Record. Cambridge University Press, 1-28. --

486

REFERENCES

--,

EYLES, C. H. & M~LL, A. D. 1983. Lithofacies types and vertical profile models: an alternative approach to the description and environmental interpretation of glacial diamict and diamictite sequences. Sedimentology, 30, 393-410. EZAKt, Y. & KAWAMURA, T. 1992. Carboniferous-Permian corals from Skansen and Festningen, Central Spitsbergen: their faunal characteristics. In: NAKAMURA, K. (ed.) Investigations on the Upper Carboniferous-Upper Permian succession of West Spitsbergen 1989-1991. Hokkaido University, Sapporo, 59-76. --, -& NAg~MURA, K. 1991. Kapp Starostin Formation in Spitsbergen: a sedimentary and faunal record of Late Permian paleoenvironments in an Arctic region. Canadian Society of Petroleum Geologists, Memoir, 17, 647-655. FAGEPa~AND, N. 1994. Barents Sea Shelf (Norway and Russia). In: KULKE, H. (ed.)

Beitrage zur regionalen Geologie der Erde, Petroleum Geology of the World. Part 1. Europe and Asia, 121-130. FAmBAIRN, P. E. 1933. The petrology of the Hecla Hook Formation in central Spitsbergen. Geological Magazine, "70, 437-454. FAIRCHILD, I. J. 1982. The Orustdalen Formation of Broggerhalvoya, Svalbard: a fan delta complex of Dinantian/Namurian age. Polar Research, 1, 17-34. - - 1 9 8 3 . Effects of glacial transport and neomorphism on Precambrian dolomite crystal sizes. Nature, 304, 714-716. - - 1 9 8 9 . Carbonate mineralization in stromatolites. In: Abstracts of the 28th International Geological Congress, 1. Washington, DC, 470. - - 1 9 8 9 . Origins and utility of carbonate in glacial facies. In: Abstracts of the 28th International Geological Congress, 1. Washington, DC, 470. - - 1 9 9 1 . Origins of carbonate in Neoproterozoic stromatolites and the identification of modern analogues. Precambrian Research, 53, 281-299. & HAMBREY, M. J. 1984. The Vendian succession of northeastern Spitsbergen: petrogenesis of a dolomite-tillite association. Precambrian Research, 26, 111-167. & 1995. Vendian basin evolution in East Greenland and N.E. Svalbard. Precambrian Research, 73, 217-233. & SPIgO, B. 1987. Petrological and isotopic implications of some contrasting Late Precambrian carbonates. Sedimentology, 34, 973 989. & 1990. Carbonate minerals in glacial sediments: geochemical clues to palaeoenvironments, ln: DOWDESWELL,J. A. & SCOURSE, J. D. (eds) Glacimarine Environments: Processes and Sediments. Geological Society, London, Special Publications, 53, 201-216. , HAMBREY, M. J., SPIRO, B. & JEFFERSON, T. H. 1989. Late Proterozoic glacial carbonates in northeast Spitsbergen: new insights into the carbonate-tillite association. Geological Magazine, 126, 469-490. , KNOLL, A. H. & SWETT, K. 1991. Coastal lithofacies and biofacies associated with syndepositional dolomitization and silicification (Draken Formation, Upper Riphean, Svalbard). Precambrian Research, 53, 165-197. FALCON, N. L. 1928. Appendix III: geology. In: The Cambridge expedition to Edge Island (ed. H. G. Watkins). Geographical Journal, 72, 134-139. FALEIDE, J. I., GUDLAUGSSON,S. T. & JACQUART, G. 1984. Evolution of the western Barents Sea. Marine and Petroleum Geology, 1, 123-150. HANKEN, N.-M. 1988. Seismic structure of Spitsbergen: implications for Tertiary deformation. In: DALLMANN, W. K., OHTA, Y. & ANDRESEN, A. (eds) Tertiary Tectonics of Svalbard. Norsk Polarinstitutt, Report Series, 46, 47 50. , ELDHOLM, O., MYHRE, A. M. & JACKSON, H. R. 1991. Deep seismic transects across the sheared western Barents Sea-Svalbard continental margin. Tectonophysics, 189, 71-89. --, MYHRE, A. M. & ELDHOLM, O. 1988. Early Tertiary volcanism at the western Barents Sea margin. In: MORTON, A. C. & PARSON, L. M. (eds) Early Tertiary Volcanism and the Opening of the NE Atlantic. Geological Society, London, Special Publications, 39, 135-146. , SOLHEIM,m., FIEDLER, A., HJELSTUEN,B. O., ANDERSEN, E. S. & VANNESTE, K. 1996. Late Cenozoic evolution of the western Barents Sea-Svalbard continental margin. Global and Planetary Change, 12, 53-74. FEDEN, R. H., VOGT,P. R. & FLEMING,H. S. 1979. Magnetic and bathymetric evidence for the "Yermak hot spot" NW of Svalbard in the Arctic basin. Earth and Planetary Science Letters, 44, 18-38. FEDOROWSKI, J. 1964. On Late Palaeozoic Rugosa from Hornsund Vestspitsbergen (preliminary communication). In: BIRKENMAJER, K. (ed.) Geological Results of Polish 1957-1958, 1959, and 1960 Spitsbergen Expeditions. Studia Geologica Polonica, 11, 139-146. - - 1 9 6 5 . Lower Permian Tetracoralla of Hornsund, Vestspitsbergen. In: BIRKENMAJER, K. (ed.) Geological Results of the Polish 1957-1958 1959 1960 Spitsbergen Expeditions. Studia Geologica Polonica, 17, 5-169. - - 1 9 6 7 . The Lower Permian tetracoralla and tabulata from Treskelodden, Vestspitsbergen. Norsk Polarinstitutt Skrifter, 142. - - 1 9 7 5 . On some Upper Carboniferous Coelenterata from Bjornoya and Spitsbergen. Acta Geologica Polonica, 25, 27-78. --1982. Coral thanatocoenoses and depositional environments in the upper Treskelodden beds of the Hornsund area, Spitsbergen. In: BIERNAT, G. & SZYMANSKA, W. (eds) Palaeontological Spitsbergen Studies. Palaeontologica Polonica, 43, 17-68. FEILDEN, H. W. 1896. Notes on the glacial geology of Arctic Europe and its islands. Quarterly Journal of the Geological Society of London, 52, 5 ~ 6 5 & 721-741. FEYHNG-HANSSEN, R. W. 1950. Changes of sea level in West Spitsbergen. A new interpretation. Geological Journal, 115, 000~00. - - 1 9 5 2 . Conglomeratesformed in situ on the Gipshuken coastalplain, Vestspitsbergen. Norsk Polarinstitutt Meddeleser, 71. - - 1 9 5 3 . The barnacle Balanus balanoides (Linn6 1766) in Spitsbergen. Norsk Polarinstitutt Skrifter, 98, 1-64. - - 1 9 5 5 a . Stratigraphy of the marine Late-Pleistocene of Billefjorden, Vestspitsbergen. Norsk Polarinstitutt Skrifter, 107, 1-186

-

-

-

-

-

-

-

-

,

EIKEN,

O.

&

Late-Pleistocene of Billefjorden, Vestspitsbergen. Norsk Polarinstitutt Skrifter, 108, 1-21. - - 1 9 5 5 c . Late-Pleistocene deposits at Kapp Wijk, Vestspitsbergen. Norsk Polarinstitutt Skrifter, 108, 1-21. - - 1 9 6 4 . A marine section from the Holocene of Talavera on Barentsoya in Spitsbergen, with a record of the Foraminifera. Norsk Polarinstitutt Meddelesen, 93, (Vortr~ige des Fridtjof-Nansen Ged~ichinis-Symposions fiber Spitsbergen 3-11 April 1961 im Wfirzburg. Steiner Vertag, Wiesbaden), 30-58. - - 1 9 6 5 . Shoreline displacement in central Vestspitsbergen and a marine section from the Holocene of Talavera on Barentsoya in Spitsbergen. Norsk Polarinstitutt Meddeleser, 93. - - 1 9 7 2 . The foraminifer Elphidium excavatum (Terquem) and its variant forms. Micropalaeontology, 18, 337-354. & JORSTAD, F. A. 1950. Quaternary fossils from the Sassen-Area in Isfjorden, West-Spitsbergen (the main Mullusc fauna). Norsk Polarinstitutt Skrifter, 94. & OLSSON, I. 1960. Five radiocarbon datings of Post Glacial shorelines in central Spitsbergen. Norsk Geographisk Tidsskrift, 17, 122-131 (also Norsk Polarinstitutt Meddelsen, 86). -& ULLEBERG,K. 1984. A Tertiary-Quaternary section at Sarsbukta, Spitsbergen, Svalbard, and its foraminifera. Polar Research, 2, 77-106. FIRSOV, L. V. & Llvsmzs, Y. Y. 1967. [Potassium-argon dating of dolerites around Sassenfjorden (West Spitsbergen)]. In: SOKOLOV, V. N. (ed.) Materialy po stratigrafii Shpitsbergena ]Materials on the stratigraphy of Spitsbergen]. NIIGA, Leningrad, 178-184. FLEMING, K. M., DOWDESWELL, J. A. & OELEMANS, J. 1997. Modelling the mass balance of northwest Spitsbergen glaciers and responses to climate change. Annals' of Glaciology, 24, 203-210. FLEMING, W. L. S. 1934. Geology, Geomorphology, and Glaciology. A. New Friesland. In: GLEN, A. R. (ed.) The Oxford University expedition to Spitsbergen 1933. Geographical Journal, 84, 116-117. & EDMONDS, J. M. 1941. Hecla Hoek rocks of New Friesland (Spitsbergen). Geological Magazine, 78, 405-428. FLOOD, B. 1965. Forholdet sedimenter-vulkanitter innen Kapp Hansteen Formasjonen (gruppen) Nordaustlandet, Svalbard (abstract). Geologi (Helsinki), 17, 130. - - 1 9 6 8 . On the contact between the Hecla Hoek and the Culm, Vestspitsbergen. Norsk Polarinstitutt /lrbok 1966, 7-11. - - 1 9 6 9 . Sulphide mineralizations within the Hecla Hoek complex in Vestspitsbergen and Bjornoya. Norsk Polarinstitutt /lrbok 1967, 109-127. , GEE, D. G., HJELLE, m., SIGGERUD, T. & WINSNES, T. 1969. The geology of Nordaustlandet, northern and central parts. Norsk Polarinstitutt Skrifter, 146. , NAGY, J. & WINSNES, T. S. 1971a. Geological Map of Svalbard. 1: 500000. Sheet IG, Spitsbergen southern part. Norsk Polarinstitutt Skrifter, 154A. --& 1971b. The Triassic succession of Barentsoya, Edgeoya and Hopen (Svalbard). Norsk Polarinstitutt Meddelelser, 100. FLOWER, B. P. 1995. Farthest North: Ocean drilling in the Arctic Gateway Region. For O.D.P. Leg 151 Shipboard Scientific Party. GSA Today, 5, 31-33. - - 1 9 9 7 . Overconsolidated section on the Yermak Plateau, Arctic Ocean: ice sheet grounding prior to ca. 660 ka? Geology, 25, 147-150. FOERSTE, A. P. 1921. Notes on Arctic Ordovician and Silurian cephalopods chiefly from Boothia Felix, King William Land, Bache Peninsula, and Bear Island. Journal of the Science Laboratories of Denison University, 19, 247-306. FOKINA, Y. I. 1980. [Petrographic characteristics of the coals of the Barentsburg deposit, Spitsbergen]. In: SEMEVSKIY,D. V. (ed.) Geologiya Osadochnogo Chekhla Arkhipelaga Sval'bard. Sbornik Nauchnykh TrudGE [Geology of the Sedimentary Mantle of the Svalbard Archipelago. A Collection of Scientific Papers]. NIIGA, Leningrad, 95-99. FOLK, R. L. & SIEDLECKA,A. 1974. The 'schizohaline' environment and its sedimentary and diagenetic fabrics as exemplified by Late Paleozoic rocks of Bear Island, Svalbard. Sedimentary Geology, 11, 1-15. FORBES, C. L. 1960. Carboniferous and Permian Fusulinidae from Spitsbergen. Palaeontology, 2, 210-225. --, HARLAND, W. B. & HUGHES, N. F. 1958. Palaeontological evidence for the age of the Carboniferous and Permian rocks of central Vestspitsbergen. Geological Magazine, 95, 465-480. FORMAN, S. L. 1990. Post-glacial relative sea-level history of northwestern Spitsbergen, Svalbard. Geological Society of America Bulletin, 102, 1580-1590. - - 1 9 9 2 . Post-glacial relative sea-level history of northwestern Spitsbergen, Svalbard: reply. Geological Society of America Bulletin, 104, 1064-1066. , MANN, D. H. & GIEEORO, H. M. 1987. Late Weichselian and Holocene relative sea-level history of Brrggerhalvrya, Spitsbergen. Quaternary Research, 27, 41-50. ,9 LUBINSKI,D., MILLER, G. H., SNYDER,J., MATISHOV,G., KORSUN, S. & MYSLIVETS, V. 1995. Postglacial emergence and distribution of Late Weichselian ice-sheet loads in the northern Barents and Kara seas, Russia. Geology, 23,113-116. FORSBERG,A. & ]]JOROY,M. 1983. A sedimentological and organic geochemical study of the Botneheia Formation, Svalbard, with special emphasis on the effects of weathering on the organic matter in shales. In: BJOROY,M. ALBRECHT,P.CORNFORD, C. et al. (eds) Advances in Organic Geochemistry 1981. Wiley, Chichester, 60-68. FORTEY, R. A. 1971. Tristichograptus, a triserial graptolite from the Lower Ordovician of Spitsbergen. Palaeontology, 14, 188-199. - - 1 9 7 4 . The Ordovician trilobites of Spitsbergen I. Olenidae. Norsk Polarinstitutt Skrifter, 160, 1-129. - - 1 9 7 4 . Opopeciter, a new pelagic trilobite from the Ordovician of Spitsbergen, Western Ireland and Utah. Palaeontology, 17, 111-124. --1975. The Ordovician trilobites of Spitsbergen II. Asaphidae, Nileidae, Raphiophoridae and Telephinidae of the Valhalla Formation. Norsk Polarinstitutt Skrifter, 162, 1~07. --t955b.

-

-

-

-

-

-

REFERENCES 1975. Early Ordovician trilobite communities. Fossils and Strata, 4, 339-360. - - 1 9 7 6 . Correlations of shelly and graptolitic Early Ordovician successions, based on the sequences in Spitsbergen. In: BASSEa'X,M. G. (ed.) The Ordovician System. Cardiff: University of Wales Press and National Museum of Wales, Cardiff, 263-280. - - - 1 9 8 0 . The Ordovician trilobites of Spitsbergen. II: Remaining trilobites of the Valhallfonna Formation. Norsk Polarinstitutt Skrifter, 171, 1-168. & BARNES, C. R. 1976. Early Ordovician trilobite and conodont communities and their influence on biogeography. In: International Geological Congress Resumes, Section 7, 303-304. & --1977. Early Ordovician conodont and trilobite communities of Spitsbergen: influence on biogeography. Aleheringa, 1, 297-309. - & BRUTON,D. L. 1973. Cambrian-Ordovician rocks adjacent to Hinlopenstretet, north Ny Friesland, Spitsbergen. Geological Society of America Bulletin, 84, 2227-2242. & HOLDSWORTH, B. K. 1971. The oldest known well-preserved radiolaria. Bollettina della Societd Paleontologica Italiana, 10, 35-41. - - - & MORRIS, S. F. 1978. Discovery of Nauplius-like trilobite larvae. Palaeontology, 21,823-833. - & WHITTAKER, J. E. 1976. Janospira; an Ordovician microfossil in search of phylum. Lethaia, 9, 397-403. , HARPER, D. A. T., INGHAM, J. K., OWEN, A. W. & RUSHTON, A. W. A. 1995. A revision of Ordovician series and stages from the historical type area. Geological Magazine, 132, 15-30. FOUNTAIN, D. M. & TREGUS, S. H. 1995. Editors raise the roof over the shingling. Geology, 23, 867. Fovy, S. 1937. The Eo-Cambrian series of the Tana district, Northern Norway. Norsk Geologisk Tidsskrift, 17, 65-163. & HEINTZ, A. 1943. The Downtonian and Devonian vertebrates of Spitsbergen.

In: The English-Norwegian-Swedish Spitsbergen Expedition 1939, VIII. Geological Results. Skrifter om Svalbard og Ishavet, 85, 1-51. FRAAS, O. 1872. Description of Triassic and Jurassic fossils from Spitsbergen. Neues Jahrbuch ffir Mineralogie, Geologie und Pal(iontologie, 1872, 203-206. FRAKES, L. A. 1979. Climates through Geologic Time. Elsevier, Amsterdam. -& FRANOS, J. E. 1988. A guide to Phanerozoic cold polar climates from highlatitude ice-rafting in the Cretaceous. Nature, 333, 547-549. FRANCE SERVICEHYDROGRAPHIQUE1950. Chapter 7: Svalbard-Bjornoya, Vestspitsbergen, Barentsoya, Edgeoya, Kong Karls Land, Nordaustlandet. In: Islande et Faer6e, Jan Mayen, Svalbard-Groenland: Cdte Est. Imprimerie Nationale, Paris. In: No. 2 1955. Instructions nautiques sdr. E IV (437), 13p. FREBOLD, H. 1928. Das Festungsprofil auf Spitzbergen. Jura und Kreide. II. Stratigraphie. Skrifter om Svalbard og Ishavet, 19, 1-39. - - 1 9 2 8 . Stratigraphie und Pal/iogeographie des Jura und der Kreide Spitzbergens. Zentralblatt Mineralogie and Paldntologie, B12, 625-629. - - 1 9 2 9 a . Oberer Lias und Unteres Callovien in Spitzbergen. Skrifter om Svalbard og Ishavet, 20, 1-24. - - 1 9 2 9 b . Ammoniten aus dem Valanginien yon Spitzbergen. Skrifter om Svalbard og Ishavet, 21, 1-24. - - 1 9 2 9 e . Die Schichtenfolge des Jura und der Unterkreide an der Ostfiste SfidwestSpitzbergens. Abhandlungen der Naturwissenschaftlichen Vereinigung Hamburg, 22, 251-292. - - 1 9 2 9 d . Untersuchungen fiber die fauna, die stratigraphie und paldogeographie der Trias Spitzbergens. Skrifter om Svalbard og Ishavet, 26, 1-66. - - 1 9 2 9 . Faunistisch-stratigraphische Untersuchungen fiber die Trias Spitzbergens und der Edge Insel. Abhandlungen der Naturwissenschaftlichen Vereinigung Hamburg, 22, 293-312. - - 1 9 3 0 a . Verbreitung und Ausbildung des Mesozoikums in Spitzbergen nebst einer Revision der Stratigraphie des Jura und der Unterkreide in Nowaja Semlja und einem Entwurf der mesozoischen Entwicklungsgeschichte des Barents-seeschelfes. Skrifter om Svalbard og Ishavet, 31, 1-126. - - 1 9 3 0 b . Die Alterstellung des Fischhorizontes, des Grippianiveaus und des unteren Saurienhorizontes in Spitzbergen. Skrifter om Svalbard og Ishavet, 28. --1930c. Die mesozoische Entwinklung des Barentsseeschelfes. Geologische Rundschau, 21, 343-345. - - 1 9 3 0 d . Neuere Forschungen fiber die Geologic Gr6nlands, Spitzbergens und der Bfireninsel. Naturwissenschaften, 18, 576-585. - - 1 9 3 1 . Fazielle Verhdltnisse des Mesozoikums im Eisfordgebiet Spitzbergens. Skrifter om Svalbard og Ishavet, 37, 1-94. - - 1 9 3 1 . Geologische Ergebnisse und Aufgaben der Arktisforschung. Geologische Rundschau, 22, 29-40. - - 1 9 3 1 . Ober die wissenschaftliche Erforschung und wirtschaftliche Bedeutung Spitzbergens. Nordisehe Rundschau 1931, 9-17. - - 1 9 3 1 . Die Kohlenlager Svalbards. Z. Oberschles. Berg-und Hfittenmaennisches Ver., 5, 1-5. - - 1 9 3 2 . Parallele Zfige im geologischen Bau Ostgr6nlands, Spitzbergens, der Bfireninsel sowie Norwegens und ihre Bedeutung. Naturwissensehaften, 20, 799-806. - - 1 9 3 4 . Tatsachen und Deutungen zur Geologic der Arktis. Meddelelserfra Dansk Geologisk Forening, 8, 301-326. -(ed.) 1935. Geologic yon Spitzbergen, der Bdreninsel des K6nig Karl und FranzJoseph Landes. Geologic der Erde, Berlin. - - 1 9 3 6 . Zur Stratigraphie des oberen Jungpalfiozoikums und der /ilteren Eotrias Spitzbergens. In: Stille Festschrift, Stuttgart, 314-346. - - 1 9 3 7 . Das Festungsprofil auf Spitzbergen. IV. Die Braehiopoden und Lamellibranchiatenfauna und die Stratigraphie des Oberkarbons und Unterperms. Skrifter om Svalbard og Ishavet, 69, 1-94. - - 1 9 3 9 . Das Festungsprofil auf Spitzbergen. V. Stratigraphie und Invertebratenfauna der d'lteren Eotrias. Skrifter om Svalbard og Ishavet, 77, 1-58.

487

- - 1 9 4 0 . Der geologische Bau Nowaja Semljas und seine Beziehung zu anderen Gebieten im Lichte neuerer Forschungen. Geologische Rundschau, 31, 634-647. - - 1 9 4 2 . Ober die Productiden des Brachiopodenkalkes und der Mallemukformation

des ndrdlichen Ostgrdnland und die Altersfrage einiger jungpaldozoischer Bildungen der Arktis. Skrifter om Svalbard og Ishavet, 84, 1-68. - - 1 9 5 1 . Geologic des Barentsschelfes. Abhandlungen der Deutschen Akademie der Wissensehaften zu Berlin 1950, 1-151. --& STOLL, E. 1937. Das Festungsprofil auf Spitzbergen. IlL Stratigraphie und Fauna des Juras und der Unterkreide. Skrifter om Svalbard og Ishavet, 68, 1-86. FREDERIKS, G. 1934. The Permian fauna of the Kanin Peninsula. Trudy Arkt. Inst., 13, 5-42 [in Russian with English summary]. FREIMUTH, B. 1909. Die Steinkohlenvorkommen Spitzbergens und der B~ireninsel. Glfickauf, 45, 1750-1756. FRIEND, P. F. 1961. The Devonian stratigraphy of north and central Vestspitsbergen. Proceedings of the Yorkshire Geological Society, 33, 77-118. - - 1 9 6 5 . Fluviatile sedimentary structures in the Wood Bay Series (Devonian) of Spitsbergen. Sedimentology, 5, 39-68. - - 1 9 6 7 . Tectonic implications of sedimentation in Spitsbergen and midland Scotland. In: International Symposium on the Devonian System, Calgary 1967, 2. Alberta Society of Petroleum Geologists, Calgary, 1141-1147. - - 1 9 6 9 . Tectonic features of Old Red sedimentation in North Atlantic Border. In: PITCHER, M. G. (ed.) Arctic Geology. Memoirs of the American Association of Petroleum Geologists, 12, 703-719. - - 1 9 6 9 . The significance of 'limonite' in the colouring of a red-bed. In: Proceedings of the 7th International Sedimentological Congress, 41, 690-694. - - 1 9 7 3 . Devonian stratigraphy of Greenland and Svalbard. Memoirs of the American Association of Petroleum Geologists, 19, 469-470. - - 1 9 7 8 . Distinctive features of some ancient river systems. In: MIALL, A. D. (ed) Fluvial Sedimentology Memoirs of the Canadian Society of Petroleum Geologists, 5, 531-542. - - 1 9 8 1 . Devonian sedimentary basins and deep faults of the northernmost Atlantic borderlands. In: KERR, J. W., FER6USSON, A. J. & MACHAN, L. C. (eds) Memoirs of the Canadian Society of Petroleum Geologists, 7, 149-166. & MOODY-STUART,M. 1970. Carbonate deposition on the river floodplains of the Wood Bay Formation (Devonian) of Spitsbergen. Geological Magazine, 107, 181-195. & - - 1 9 7 2 . Sedimentation of the Wood Bay Formation (Devonian) of Spitsbergen: regional analysis of a late orogenic basin. Norsk Polarinstitutt Skrifter, 157, 1-77. , HARLAND, W. B., ROVERS, D. A., SNAPE, I. & THORNEY, S. 1997. Late Silurian and Early Devonian stratigraphy and probable strike-slip tectonism in northwestern Spitsbergen. Geological Magazine, 134, 459-479. MOODY-STUART, M. 1966. New unit terms for the Devonian of Spitsbergen and a new stratigraphical scheme for the Wood Bay Formation. Norsk Polarinstitutt flrbok 1965, 59-64. FRITZ, W. H. & YOCHELSON,E. L. 1988. The status of Salterella as a Lower Cambrian index fossil. Canadian Journal of Earth Sciences, 25, 403-416. Fucns, T. 1883. Uber die w/ihrend der schwedischen geologischen Expedition nach Spitzbergen im Jahre 1882 gesammelten Tertitirconchylien. Bih. Kungliga Svenska Vetenskapsakademiens Handlinger, 8, 1-11. Uppsala & Stockholm. FuJII, Y. & 10 OTnERS 1990. 6000-year climate records in an ice core from the Hoghetta ice dome in northern Spitsbergen. Annals of Glaciology, 14, 85-89. FURnES, H., PEDERSEN, R. B. & MAALOE, S. 1986. Petrology and geochemistry of spinel peridotite nodules and host basalt, Vestspitsbergen. Norsk Geologisk Tidsskrift, 66, 53-68. FURRER, G. 1994. Zur Gletschergeschichte des Liefdefjords, NW-Spitsbergen (1 Figure+ 1 Table). Zeitsehriftffir Geomorphologie, 97, 43-48. GABRIELSEN, R. H. 1984. Long-lived fault zones and their influence on the tectonic development of the southwestern Barents sea. Journal of the Geological Society, London, 141, 651-662. -& FmRSETH, R. B. 1988. Cretaceous and Tertiary reactivation of master fault zones of the Barents Sea. In: DALLMANN,W. K., OHTA, Y, & ANI~RESEn, A. (eds) Tertiary Tectonics of Svalbard. Norsk Polarinstitutt, Report Series, 46, 93-98. & KOESTLER, A. G. 1985. First meeting of the Tectonic and Structural Studies Group of N G F on "Fault Tectonics of the Norwegian Mainland, Svalbard and Continental Shelf". Norsk Geologisk Tidsskrift, 65, 217-220. & - - 1 9 8 5 . Second meeting of the Tectonics and Structural Geology Studies Group of N G F on "Dating of Structural Events". Norsk Geologisk Tidsskrift, 65, 321 324. --, FOERSETH, R., HAMAR, G. & R.NNEVlK, H. 1984. Nomenclature of the main structural features on the Norwegian continental shelf north of the 62nd parallel. In: SPENCER, A. M. et al. (eds) Petroleum Geology of the North European Margin. Graham and Trotman, London, 41-60. --, GRUNNALE1TE, I. & OTTESEN, S. 1992. Reactivation of fault complexes in the Loppa High area, southwest Barents sea. In: VORREN, T. O. (ed.) Arctic Geology and Petroleum Potential, NPF Special Publications, 2, 631-641. --, -& RASMUSSEN, E. 1997. Cretaceous and Tertiary inversion in the Bjornorenna Fault Complex, South-western Barents Sea. Marine and Petroleum Geology, 14, 165-178. --, KLOVJAN,O. S., HAUGSBO, H., MIDBOE, P. S., NOTTVEDT,A., RASMUSSEN, E. & SKoa-'r, P. H. 1992. A structural outline of Fodandsundet Graben, Prins Karls Forland, Svalbard. In: DALLMANN,W. K., ANDRESEN,A. & KRILL, A. (eds) PostCaledonian Tectonic Evolution of Svalbard. Norsk Geologisk Tidsskrift, 72,105-120. GARDINER, J. S. 1887. On the leaf-beds and gravels of Ardtun, Carsaig etc. in Mull with notes by G. A. Cole. Quarterly Journal of the Geological Society of London, 43, 270-300. -

-

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-

H E I N T Z ,

N.

&

488

REFERENCES

GARWOOD, E. J. & GREGORY, J. W. 1896. The geological work of the Conway Spitsbergen expedition. Geological Magazine, 3, 437-439. - & 1898. Contribution to the glacial geology of Spitsbergen. Quarterly Journal of the Geological Society of London, 54, 197-225. GAVRILENKO, B. V. & KAMENSKIY,I. L. 1992. [K-Ar isochronous age and potassium isotopes in the ultrabasic dyke on the Mossel Peninsula, Ny Friesland Spitsbergen]. Geokhimika, 2, 124-129. , BmJuKOV, A. S. & EVDOKIMOVA,N. K. 1996. Correlation of Carboniferous and Permian successions, Billefjorden area, and coal, gypsum and bitumen occurrences in them. In: KRASIL'SHCHIKOV, A. A (eds) Soviet Geological Research in Svalbard 1962-1992. Norsk Polarinstitutt Meddelelser, 139, 53, (Oslo 1996). GAYER, R. A. (ed.) 1989. The Caledonide Geology of Scandinavia. Graham & Trotman, London. - - 1 9 6 9 . The geology of the Femmilsjoen region of the north-west of Ny Friesland, Spitsbergen. Norsk Polarinstitutt Skrifter, 145, 1-45. -(~Z WALLIS, R. H. 1966. The petrology of the Harkerbreen Group of the lower Hecla Hock of Ny Friesland and Olav V Land, Spitsbergen. Norsk Polarinstitutt Skrifter, 140, 1-32. , GEE, D. G., HARLAND, W. B., MILLER, J. A., SPALL, H. R., WALLIS, R. H. & WINSNES, T. S. 1966. Radiometric age determinations on rocks from Spitsbergen. Norsk Polarinstitutt Skrifter, 137, 1-39. GAZDZICK~, A. & TRAMMER, J. 1977. The sverdrupi zone in the Lower Triassic of Svalbard. Acta Geologica Polonica, 27, 349-356. -& 1978. Tidal deposits in the Lower Triassic of Svalbard. Neues Jahrbuchfffr Geologic und Palaontologie, Monatsehefte, 8, 321-331. GECO 1977-1986. Seismic section of Svalbard stacked sections many lines each on one of17 sheets. Bergen University and STATOIL and GECO, Stavanger. GEE, D. G. 1966. A note on the occurrence of eclogites in Spitsbergen. Norsk Polarinstitutt ~lrbok 1964, 240-241. - - 1 9 7 2 . Late Caledonian (Haakonian) movements in northern Spitsbergen. Norsk Polarinstitutt Arbok 1970, 92-101. - - 1 9 8 6 . Svalbard's Caledonian terranes reviewed. Geologiska F6reningens Stockholm Fdrhandlingar, 108, 284-286. - - 1 9 8 9 . Iapetus opening in the North Atlantic - along the axis of the Grenville Orogen? Geologiska F6reningens Stockholm Fdrhandlingar, 111, 383-385. - - 1 9 9 4 . Svalbard's Caledonian terranes. In: KARLQVIST,X. & CARLSSON, X. (eds) Swedish Research in Svalbard. Swedish Polar Research Secretariat, Stockholm, 92-117. - - 1 9 9 6 . Eastern Svalbard's three major Precambrian unconformities and their Caledonian deformation. Unconformities and Tectonic Events. In: Norwegian Geological Society, Program with Abstracts, 7-8 Nov 1996, University of Oslo. & HELLMAN, F. 1996. Zircon Pb-evaporation ages from the Smutsbreen Formation, southern Ny Friesland: new evidence for Caledonian thrusting in Svalbard's Eastern Terrane. Zeitschaft Geologische Wissenschaft, 429-439 - & HJELLE, A. 1966. On the crystalline rock of northwest Spitsbergen. Norsk Polarinstitutt .4rbok 1964, 31-45. - & MOODY-STUART,M. 1966. The base of the Old Red Sandstone in central north Haakon VII Land, Vestspitsbergen. Norsk Polarinstitutt ,4rbok 1964, 57-68. --& PAGE, L. M. 1994. Caledonian terrane assembly on Svalbard: new evidence from 4~ dating in Ny Friesland. American Journal of Science, 294,1166-1186. -& STURT, B. A. (eds) 1985. The Caledonide Orogen - Scandinavia and Related Areas, Wiley, Chichester. - & TEBENKOV,A. M. 1996. Two major unconformities beneath the Neoproterozoic Murchisonfjorden Supergroup in the Caledonides of central Nordaustlandet, Svalbard. Polar Research, 15, 81-91. -& ZEYEN, H. J. (eds) 1996. EUROPROBE 1996. Lithosphere Dynamics: Origin and Evolution of Continents, EUROPROBE Secretariate, Uppsala University. , BJORKLUND, t. & STOLEN, L.-K. 1994. Early Proterozoic basement in Ny Friesland - implications for the Caledonian tectonics of Svalbard. Tectonophysics, 231, 171-182. , JOHANSSON,,~., OHTA, Y. & TEBEN'KOV,A. 1993. The pre-Caledonian history of Nordaustlandet and Ny Friesland, Svalbard. Geonytt, 1193, 21-22. , KRASIL'SHCHIKOV,A. A., BALASHOV,Y. A., LARIONOV,A. N., GANNIBAL, L. F. & RYUNGENEN, G. I. 1995. Grenvillian basement and a major unconformity within the Caledonides of Nordaustlandet, Svalbard. Precambrian Research, 70, 215-234. , SCHOUENBORG, B . , PEUCAT, J.-J., ABAKUMOV, S. A., KRASIL'SHCHIKOV,A. A. & TEBEN'KOV, A. M. 1992. New evidence of basement in the Svalbard Caledonides: Early Proterozoic zircon ages from Ny Friesland granites. Norsk Geologisk Tidsskrift, 72, 181-190. GEE, R., HARLAND, W. B. & MCWHAE, J. R. H. 1953. Geology of central Vestspitsbergen. Part I. Review of the geology of Spitsbergen with special reference to central Vestspitsbergen. Part II. Carboniferous to Lower Permian of Billefjorden. Transactions of the Royal Society of Edinburgh, 62, 299-356. GENSHAFT, Y. S. & ILUPIN, I. P. 1987. [Mineralogy of the products of Quaternary volcanism of Spitsbergen]. Doklady Akademii Nauk SSSR, 295, 694-699. , DASHEVSKAYA, D. M., YEVDOKIMOV, m. N. & KOPYLOVA, M. G. 1992. [Abundance and shape of plutonic ultramafic inclusions in alkalic basalt from Spitsbergen]. Doklady Akademia Nauk, 326, 116-122. GEORGE, T. N., AGER, D. V., BLOW, W. H., CASEY, R., HARLAND, W. B., HOLLAND, C. H., HUGHES, N. F., KELEAWAY, G. A., KENT, P. E., RAMSBOTTOM,W. H. (~ RHODES, F. H. T. 1969. Recommendations on stratigraphic usage. Geological Society of London, Proceedings, 1956, 149-166. GI~RARD, J. & BUHRIG, C. 1990. Seismic facies of the Permian section of the Barents shelf: analysis and interpretation. Marine and Petroleum Geology, 77, 234-252. GERBER, E. 1948. Versteinertes Leben aus Spitzbergen. Prisma, 3, 113-116.

(GERMANY) KRIEGSMARINEOBERKOMMANDO1916-1943. Spitzbergen-Handbuch. E. S. Mittler and Sohn, Berlin. GILBERT, R. 1990. Rafting in glacimarine environments. In: DOWDESWELL,J. A. & SCOURSE, J. D. (eds) Glacimarine Environments: Processes and Sediments. Geological Society, London, Special Publications, 53, 105-120. GINSBURG, L. & JANVIER, P. 1976. Un nouveau gisement a P16siosaures darts la Jurassique du Spitsbergen (Archipel du Svalbard). Norsk Polarinstitutt Arbok 1974, 262-265. GmMOIrNSKY, A. 1927. La faune du Jurassique sup~rieur et du Crdtacd inf~rieur de

Spitsberg. Berichte des Wissensch. Meeresinstituts 4. GJELBERG, J. G. 1978. Facies analysis of the coal-bearing Vesalstranda Member (Upper Devonian) of Bjornoya. Norsk Polarinstitutt .4rbok 1977, 71-100. --t981. Upper Devonian (Famennian)-Middle Carboniferous succession of Bjornoya: a study of ancient alluvial and coastal marine sedimentation. Norsk Polarinstitutt Skrifter, I74, 1-67. - - 1 9 8 7 . Upper Devonian to Middle Carboniferous. In: MORK, A. (ed.) Geological Excursion Guide to Bjornoya. IKU, Trondheim. - - 1 9 8 7 . Early Carboniferous graben style and sedimentation response, Svalbard. In: MILLER, J., ADAMS, A. E. & WRIGHT, V. P. (eds) European Dinantian Environments. Geological Journal Special Issues, 12, 93-113. - & STEEL, R. J. 1979. Middle Carboniferous sedimentation in relation to tectonic, climatic and sea level changes on Bjornoya and Spitsbergen. In: Norwegian Sea Symposium, (NSS/27). Norwegian Petroleum Society, Tromso, 1-25. - & 1981. An outline of Lower-Middle Carboniferous sedimentation on Svalbard: effects of tectonic, climatic and sea level changes in rift basin sequences. In: KERR, J. W., FERGUSSON, A. J. & MACHAN, L. C. Geology of the North Atlantic Borderlands. Memoirs of the Canadian Society of Petroleum Geologists, 7, 543-562. -& 1983. Middle Carboniferous transgression, Bjorn~ya, Svalbard: facies sequences from an interplay of sea level changes and tectonics. Geological Journal, 1 8 , 1-19. & 1995. Helvetiafjellet Formation (Barremian-Aptian), Spitsbergen: characteristics of a transgressive succession. In: STEEL, R. J. (ed.) Sequence stratigraphy on the northwest European Margin, NPF Special Publications, 5, Elsevier, 571-593.. GJEESVm, T. 1963. Remarks on the structure and composition of the Sverrefjellet volcano, Bockfjorden Vestspitsbergen. Norsk Polarinstitutt Arbok 1962, 5O-54. - - 1 9 6 8 . Svalbard, Jan Mayen, Antarctic Possessions. Royal Ministry of Foreign Affairs, Department of Cultural Relations, Oslo 46. - - 1 9 7 4 . A new occurrence of Devonian rocks in Spitsbergen. Norsk Polarinstitutt ,4rbok 1972, 23-28. - - 1 9 7 9 . The Hecla Hock ridge of the Devonian Graben between Liefdefjorden and Holtedahlfonna, Spitsbergen. Norsk Polarinstitutt Skrifter, 167, 63~1. - - 1 9 8 1 . [Anders K. Orvin. A commemorative lecture at the Norwegian Academy].

Norsk Videnskaps-Akademi ,~rbok 1981, 7. - - 1 9 8 4 . The Tertiary orogenic zone of Spitsbergen and its relation to plate tectonics in the northern Greenland Sea. In: GRAMBERG,J. S. (ed.) Arctic Geology, Reports of the 27th International Geological Congress, Part 4. Nauka, Moscow, 67-84. --1991. Composition and provenance of the Lilljeborgfjellet Conglomerate, Haakon VII Land, Spitsbergen. Polar Research, 9, 141-154. - - 1 9 9 6 . Report on the basal layers of Early Devonian in Haakon VII Land, Spitsbergen. Norsk Polarinstitutt, Oslo. - & IEYES,R. 1991. Distribution of Late Silurian (?) and Early Devonian grey-green sandstones in the Leifdefjorden-Bockfjorden area, Spitsbergen. Polar Research, 9, 77-87. , EEVERHOI,A., HJELLE, A., LAURITZEN,0. • SALVIGSEN,0. 1986. Status of the geological research in Svalbard and the Barents Sea. Bulletin of the Geological Society of Finland, 58, 131 147. GLEN, A. R. 1937. The Oxford University Arctic Expedition, North East Land 1935-36. Geographical Journal, 90, 193-222, 289 314. GNILORYBOV,N. A. 1988. [Coal mines on Spitsbergen]. Nedra, Moscow. GOBHETT, D. J. 1960. A new species of trilobite from the Oslobreen Limestone, Spitsbergen. Geological Magazine, 97, 457-459. - - 1 9 6 1 . The Permian brachiopod genus, Horridonia Chao. Palaeontology, 4, 42-53. - - 1 9 6 3 . Carboniferous and Permian brachiopods of Svalbard. Norsk Polarinstitutt Skrifter, 127, 1~01. -& W~LSON,C. B. 1960. The Oslobreen Series, Upper Hecla Hock of Ny Friesland, Spitsbergen. Geological Magazine, 97, 441-457. GOES, A. 1884. [On Fusulina cylindrica Fischer from Spitsbergen]. Kungliga Svenska Vetenskapsakademiens Ofvers. ,4rg., 40, 29-35. GOLDSCHMIDT, V. M. 1911. Petrographische Untersuchung einiger Eruptivegesteine yon Nordwestspitzbergen. Skrifter udgivne af Videnskabsselskabet i Kristiania. Mat.-Naturv, 1, 1-17. GOLOVANOV, N. P. 1967. [Stromatolites of Riphean age in the region of Murchisonfjorden, Nordaustlandet]. In: SOKOLOV, V. N. (ed.) Materialy po stratigrafii Shpitsbergena, NIIGA, Leningrad, 6-20. - - 1 9 7 6 . [The vertical distribution of stromatolites in the Upper Precambrian deposits of northern Siberia and Spitsbergen]. In: SOKOLOV, B. S. et al. (eds)

Paleontology of the Precambrian and Early Cambrian. Papers presented at the AllUnion Symposium, 11 14 May 1976. Novosibirsk, 82-84. - & RAABEN, M. Y. 1967. The counterparts of the Upper Riphean in the Spitsbergen archipelago. Doklady Akademii Nauk SSSR, 173, 1141-1144. GORDIYENKO, F . G . , K O T L Y A K O V , V . M . , PUNNING, Y.-K. M. & VAIKMAE, R. 1981. Study of a 200 m ice core from the Lomonosov Ice Plateau on Spitsbergen and the Paleoclimatic implications. Polar Geography and Geology, 5, 242-251.

REFERENCES GOROCHOV, I. M., KRASIL'SHCHIKOV,A. A., MEL'NIKOV,N. N. & VARSHAVSKAYA,E. S. 1977. [Rb-Sr age of quartz porphyries of the Kapp Hansteen Series (Spitsbergen)]. In: Problemy Geokhronologii i Geokhimii Izotopov ]Problems of Geochronology and Geochemistry of Isotopes]. Nauka, Leningrad, 51-61. GORSKI, M. 1990. Seismicity of Spitsbergen Platform and its relation to geotectonics of the region. Polish Polar Research, 11, 277-285. GOTHAN, W. 1907. Die fossilen H61zer von K6nig Karls Land. Kungliga Svenska Vetenskapsakademiens Handlingar, 42, 1-44. - - 1 9 1 0 . Die fossilen Holzreste von Spitzbergen. Kungliga Svenska Vetenskapsakademiens Handlingar, 45, 1-56. - - 1 9 3 7 . Kohle. In: BEYSCHLAG,F., KRUSCH,P. & VOGT, J. H. L. Die Lagerstdtten der nutzbaren Mineralien und Gesteine, Vol. IIl(I), Stuttgart, 322-324. GOUJET, D. 1973. Sigaspis, un nouvel Arthrodire du D6vonien inf6rieur du Spitsberg. Palaeontographica Americana, 143, 73-88. - - 1 9 7 5 . Dicksonosteus, un nouvel Arthrodire du Dbvonien du Spitsberg. Remarques sur le squelette visc6ral des Dolichothoraci. In: Probldmes actuels de Pal~ontologie, Evolution des Vertebras, 218, 1. Colloque, International CNRS, 81-99. - - 1 9 8 4 . Les Poissons Placoderms du Spitsberg: Arthrodires Dolichothoraci de la Formation de Wood Bay (D~vonien Inf~rieur). Cahier Pal6ontologique, Edition du CNRS, Paris. & BLIECK, A. 1977. La faune de Vert6br6s de l'horizon 'Vogti' (Groupe de Red Bay, Spitsberg). Comparaison avec les autres faunes ichthyologiques du D6vonien inf6rieur europ6en. Comptes Rendus de l'Academie des Sciences, Paris, Series D, 1513-1515. --, JANVIER, P. t~ BLIECK, A. 1987. The vertebrate stratigraphy of the Lower Devonian (Red Bay Group and Wood Bay Formation) of Spitsbergen. Modern Geology, 11, 197-217. GRABAU, A. W. 1931. The Permian of Mongolia. Natural History of Central Asia, Part 4, New York. GRAD, C. 1866. Esquisse physique des ffes Spitzbergen et du Pdle Arctique. Paris. GRADSTEIN, F. M. & OGG, J. 1996. A Phanerozoic time scale. Episodes, 19, 3-5 & folding plate. GRAMBERG, I. S. 1959. On the interrelation of Permian and Triassic deposits in N. Central Siberia. NIIGA Leningrad, Scholarly Papers, Regional Geology, 65, 44-51. -(ed.) 1988. Barentsevskaya Shelfovaya Plita [The Barents Shelf "Plate']. Trudy NPO 'Sevmorgeo', Part 196. Nedra, Leningrad. & RONKINA,Z. Z. 1988. [Late Jurassic black clay formation of the Soviet Arctic]. Sovetskaya Geologiya, 6, 94-99. --t~ SPIRO, N. S. 1965. The palaeo-hydrochemistry of Northern Central Siberia in the Late Palaeozoic Mesozoic. Trudy NIIGA, 142. , KRASIL'SHCHIKOV,A. A. & SEMEVSKIY,D. V. 1990. Stratigraficheskiy Slovar's Shpitsbergena [Stratigraphic Lexicon of Spitsbergen], Nedra, Leningrad. --, SPIRO, N. S. & APLONOVA, E. N. 1961. Permian and Triassic' stratigraphy and -

-

2 8 4 ,

-

-

petrography of the northern portions of the Verkhoyansk foredeep and adjacent folded belts. Leningrad. --,

SHKOLA, I. V., BRO, Y. G., SHEKHODANOV,V. A. & ARMISHEV, A. M. 1985. [Parametric boreholes on the islands of the Barents and Kara Seas]. Sovetskaya Geologiya 1985, 95-98. GREEN, J. W., KNOLL, A. H., GOLUalC, S. & SWETT, K. 1987. Paleobiology of distinctive benthic microfossils from Upper Proterozoic Limestone-Dolomite 'Series', Central East Greenland. American Journal of Botany, 74, 928-940. & SWETr, K. 1989. Microfossils from silicified stromatolitic carbonates of the Upper Proterozoic Limestone-Dolomite 'Series', Central East Greenland. Geological Magazine, 126, 567-585. GREGORY, J. W. 1921. Note on the sequence across Central Spitsbergen from Advent Bay to Agardhs Bay. Geological Magazine, 58, 295-296. GRIFFIN, W. L. 8~; KRESTEN, P. 1987. Scandinavia - the carbonatite connection. In: NlXON, P. H. (ed.) Mantle Xenoliths, Wiley, Chichester, 101-106. GRn, P, K. 1927a. Beitr/ige zur Geologie von Spitzbergen. Abhandlungen der Naturwissenschaftlichen Vereinigung Hamburg, 21, 1-38. 1927b. Ergebnisse der Hamburgischen Spitzbergen-Expedition 1927. Forschungen -

-

und Fortschritte. Korrespondenzblatt der Deutschen Wissenschaft und Technik, 3, 253-254. - - 1 9 2 9 . Glaziologische und geologische Ergebnisse der Hamburgischen SpitzbergenExpedition 1927. Abhandlungen der Naturwissenschaftlichen Vereinigung Hamburg, 22, 145-249. GR~NLIE, G. 1978. Preliminary results of seismic velocity measurements in Spitsbergen in 1977. Norsk Polarinstitutt .4rbok 1977, 229-236. , ELVERHOI, A. & KRISTOFFERSEN, Y. 1980. A seismic velocity inversion on Bjornoya - the western Barents Shelf. Marine Geology, 35, M17-M28. GROSEJELD, K. 1991. Palynological age constraints on the base of the Helvetiafjellet Formation (Barremian) on Spitsbergen. Polar Research, 11, 11-19. GROSSWALD, M. G. 1980. Late Weichselian ice sheet of northern Eurasia. Quaternary Research, 13, 1-32. , DEVIRTS, A. L., DOBKINA, E. I. & SEMEVSK1Y,O. V. 1967. Crustal movements and dating of glacial stages in the Spitsbergen region. Geochemistry International, 4, 30-35. GROVE, J. M. 1988. The Little Ice Age, Methuen, London. GRtJNOW, A., HANSON, R. & WILSON, T. 1966. Were aspects of Pan-African deformation linked to Iapetus opening? Geology, 24, 1063-1066. GROSS, J. 1924. Nematiphora fascigera gen. nov., eine Devonalge als Vorldiufer der

Gymnospermen und ihre Beziehung zu einer neuen Kohlentheorie auf gdrphysiologischer Grundlage. Berlin. GRUSZCZYNSKI, M. & MALKOWSKI, K. 1987. Stable isotopic records of the Kapp Starostin Formation (Permian), Spitsbergen. Polish Polar Research, 8, 201-215.

489

, HALAS, S., HOFFMAN, A. & MALKOWSKI,K. 1989. A brachipod calcite record of the oceanic carbon and oxygen isotope shifts at the Permian/Triassic transition. Nature, 337, 64-68. --, HOEEMAN, A., MALKOWSKI,K. & VEIZER, J. 1992. Seawater strontium isotopic perturbation at the Permian-Triassic boundary, West Spitsbergen, and its implications for the interpretation of strontium isotopic data. Geology, 20, 779-782. GUDLAUGSSON,S.T. 1993. Large impact crater in the Barents Sea. Geology, 21, 291-294. --, FALEIDE, J. I., FANAVOLL, S. & JOHANSEN, I . 1987. Deep seismic reflection profiles across the western Barents Sea. Geophysical Journal of the Royal Astronomical Society, 89, 273-278. GUREVICH,Y. L. & SLAUTSITAIS,I. P. 1988. [Paleomagnetism of Mesozoic sedimentary and intrusive rocks, West Spitsbergen]. In: KHARMOV,A. N. (ed.) Paleomagnetism and Accretion Tectonics, VNIGRI, Leningrad, 18-30. GUTERCH, A. & PERCHUC, E. 1990. Seismic crustal structure of the sedimentary basin of Central Spitsbergen (discussion of results). Polish Polar Research, 11,267-276. - - , PAJCHEL,J. & PERCHUC, E. 1982. The central profile. In: SELLEVOLL,M. A. (ed.) Seismic Crustal Studies on Spitsbergen 1978. University of Bergen Seismological Observatory, Bergen, 33-62. - - , KOWALSKI,J., DUDA, S., KOMBER,J., BOJDYS,G. 8z SELLEVOLL,M. A. ]978. Seismic reconnaissance measurement of the crustal structure in the Spitsbergen region 1976. Scientific Reports of the University of Bergen Seismological Observatory, 1-61. HACZEWSKI, G. 1984. Lower Carboniferous alluvial sandy deposits (Hornsundneset Formation) of South Spitsbergen. Studia Geologica Polonica, 80, 91-98. HAGEN, J. O. 1987. Glacier surge at Usherbreen, Svalbard. Polar Research, 5, 239-252. -& LIESTOL,O. 1990. Long-term glacier mass balance investigations in Svalbard. Annals of Glaciology, 14, 102-106. & SAETRANG, A. 1991. Radio-echo soundings of sub-polar glaciers with lowfrequency radar. Polar Research, 9, 99-107. , LIESTOL, O., ROLAND, E. &; JORGENSEN, T. 1993. Glacier Atlas of Svalbard and Jan Mayen. Norsk Polarinstitutt Meddelelser, 129. HAGERMAN, T. H. 1925. Results of the Swedish expedition to Spitzbergen 1924. II. Stratigraphic and structural investigations within south-western Spitzbergen. Geografiske Annulet, 7, 195-221. H:,GG, R. 1924. Bidrag till Spetsbergens tertigirfauna. Geologiska F6reningens Stockholm F6rhandlingar, 46. - - 1 9 2 5 . A new Tertiary fauna from Spitsbergen. Bulletin of the Geological Institution of the University of Uppsala, 20, 39-56. - - 1 9 5 0 . ]Quaternary marine fossils from Spitsbergen collected by Swedish expeditions]. Geologiska F6reningens i Stockholm FSrhandlingar, 72. - - 1 9 5 1 . ]Quaternary fossils from Spitsbergen collected by Swedish expeditions]. Geologiska F6reningens i Stockholm F6rhandlingar, 73. H~GGBLOM, A. 1982. Driftwood in Svalbard as an indicator of sea ice conditions. Geografiske Annaler, 64A, 81-94. HAKANSSON,E. 1979. Carboniferous to Tertiary development of the Wandel Sea basin, eastern North Greenland. Rapport, Gronlands Geologiske Undersogelse, 88, 73-83. - - 1 9 8 8 . Did Tertiary compressional tectonics affect north Greenland? Summary of the evidence. In: DALLMANN, W. K., OHTA, Y. & ANDRESEN, A. (eds) Tertiary Tectonics of Svalbard. Norsk Polarinstitutt, Report Series, 46, 101-104. & PEDERSEN, S. A. S. 1982. Late Paleozoic to Tertiary tectonic evolution of the continental margin in north Greenland. In: EMBRY, A. F. ~; BALKWILL,H. R., Arctic Geology and Geophysics. Memoirs of the Canadian Society of Petroleum Geologists, 8, 331-348. • STEMMERIK,L. 1989. Wandel Sea basin - a new synthesis of the Late Paleozoic to Tertiary accumulation in North Greenland. Geology, 17, 683-686. HALBOUTY, M. T. 1986. Future Petroleum Provinces of the World. Memoirs of the American Association of Petroleum Geologists, 40. HALLAM, A. 1958. A Cambro-Ordovician fauna from the Hecla Hoek succession of Ny Friesland, Spitsbergen. Geological Magazine, 95, 71-76. HALLER, J. 1961. The Carolinides: an orogenic belt of late Precambrian age in northeast Greenland. In: RAASCH, G. O. (ed.) Geology of the Arctic, Vol. l, Toronto University Press, 155-159. HALLET, B. 1990. Self organization in freezing soils: from microscopic lenses to patterned ground. Canadian Journal of Physics, 68, 842-852. t~ PRESTRUD, S. 1986. Dymanics of periglacial sorted circles in western Spitsbergen. Quaternary Research, 26, 81-99. HALSTEAD, L. B. 1969. The pattern of vertebrate evolution. Oliver & Boyd, Edinburgh. HALSTEAD-TARLO,L. B. 1973; The heterostracan fishes.Biological Reviews, 48, 279-332. HALVORSEN, E. 1972. A palaeomagnetic study of two volcanic formations from northern Spitsbergen. Norsk Polarinstitutt Arbok 1970, 70-75. - - 1 9 7 3 . Demagnetization studies of the late Mesozoic dolerites from the Isfjorden area, Spitsbergen. Norsk Polarinstitutt .4rbok 1971, 17-30. - - 1 9 7 4 . The magnetic fabric of some dolerite intrusions, northeast Spitsbergen: implications for their mode of emplacement. Earth and Planetary Science Letters, 21, 127-133. - - 1 9 7 5 . Secondary Fe-spinel formation in red beds from the Wood Bay Formation, Svalbard. Norsk Polarinstitutt Arbok 1973, 73-86. HAMBERG, A. 1899. ()bet die Basalte des K6nig Karl Landes. Geologiska F6reningens Stockholm F6rhandlingar, 21, 509-532. HAMBREY, M. J. 1982. Late Precambrian diamictites of northeastern Svalbard. Geological Magazine, 119, 527-551. - - 1 9 8 3 . Correlation of Late Proterozoic tillites in the North Atlantic region and Europe. Geological Magazine, 120, 209-232. - - 1 9 8 3 . Sudden draining of ice-dammed lakes in Spitsbergen. Polar Record, 7, 189-194. - - 1 9 8 4 . Sedimentary processes and buried ice phenomena in the pro-glacial areas of Spitsbergen glaciers. Journal of Glaciology, 30, 116-119. -

-

-

-

-

-

490

REFERENCES

- - 1 9 8 8 . Late Proterozoic stratigraphy of the Barents Shelf. In: HARLAND, W. B. & DOWDESWELL, E. K. (eds) Geological Evolution of the Barents Shelf Region. Graham & Trotman, London, 49-72. - - 1 9 8 9 . The Late Proterozoic sedimentary record of East Greenland: its place in understanding the evolution of the Caledonide Orogen. In: GAYER, R. A. (ed.) The Caledonide Geology of Scandinavia. Graham & Trotman, London, 257-262. - - 1 9 9 2 . Secrets of a tropical ice age. New Scientist, 1806, 42-49. - - - & HARLAND,W. B. (eds) 1981. Earth's Pre-Pleistocene GlacialRecord. Cambridge University Press, Cambridge. & 1985. The Late Proterozoic glacial era. Palaeogeography, Palaeoclimatology, Palaeoecology, 51, 225-272. & HUDDART, D. 1995. Proglacial processes at the snout of a thermally complex glacier in Svalbard. Journal of Quaternary Science, 10, 313-326. - - - & MONCRmFF, A. C. M. 1985. Vendian stratigraphy and sedimentology of the East Greenland Caledonides. Rapport, Gronlands Geologiske Undersogelse, 125, 88-94. & SPENCER, A. M. 1987. Late Precambrian glaciation of central East Greenland. Meddelelser om Gronland Geoscience, 19. -& SWEVT, K. 1982. Rock glaciers in northern Spitsbergen: a reply. Journal of Geology, 90, 217-218. & WADDAMS, P. 1981. Deformed stones of varied lithology in Late Precambrian tillites, western Spitsbergen. Journal of the Geological Society, London, 138, 445-453. --, HARLANO, W. B. & WADDAMS, P. 1981. Late Precambrian tillites of Svalbard. Part II, Section El0. In: HAMBREY, M. J. & HARLANO, W. B. (eds) Earth's PrePleistocene Glacial Record. Cambridge University Press, Cambridge, 592-600. HAMILTON, E. I. & SANDFORD, K. S. 1964. Rubidium-strontium ages from North-East Land (Spitsbergen). Nature, 201, 1208-1209. --, HARLANO, W. B. & MILLER, J. A. 1962. Isotopic ages from some Spitsbergen rocks. Nature, 195, 1191-1192. HANISCH, J. 1984. West Spitsbergen fold belt and Cretaceous opening of the northeast Atlantic. In: SPENCER,A. M. et al. (eds) Petroleum Geology of the North European Margin, Graham & Trotman, London, 187-198. HANOA, R. 1993. Kings Bay Kull Comp. A/S 1917-1992, Schibsted, Oslo. HANSEN, A. & KNUDSEN, K. L. 1995. Recent Foraminiferal distribution in Freemansundet and Early Holocene stratigraphy on Edgeoya, eastern Svalbard. Polar Research, 14, 215-238. HANSEN-BAUER, I., KRISTENSEN, M. & STEFFENSEN, E. L. 1990. The climate of Spitsbergen. Klima, Den Norsk Meteorologisk lnstitutt, Rapport No. 39[90. HANSKY, A. 1902. Les Traverses de l'exprdition russo-suedoise pour la mbridien au Spitzberg. Revue General Scientifique, 1117 1130, 1165-1176. HAQ, B. U., HARDENBOL,J. & VAIL, P. R. 1988. Mesozoic and Cenozoic chronostratigraphy and cycles of sea level change. In: WmGUS, C. K. et al. (eds) Sea-Level Changes An Integrated Approach. SEPM Special Publication, 42, 71-108. HAREMO, P. & ANDRESEN, A. 1988. Tertiary movements along the Billefjorden Fault Zone and its relation to the Vest-Spitsbergen orogenic belt. In: DALLMANNW. K., OHTA, Y. & ANDRESEN, A. (eds) Tertiary Tectonics of Svalbard. Norsk Polarinstitutt, Report Series, 46, 71-74. & 1992. Tertiary decollement thrusting and inversion structures along Billefjorden and Lomfjorden fault zones, east central Spitsbergen. In: LARSEN, R. M., BREKKE, H., LARSEN, B. T. & TALLERAAS, E. (eds) Structural and Tectonic Modelling and its Application to Petroleum Geology. Norwegian Petroleum Society (NPF), Special Publications, Elsevier, Amsterdam, 481-494. --, -& DYPVIK, H. 1993. Mesozoic extension versus Tertiary compression along the Billefjorden Fault Zone south of Isfjorden, central Spitsbergen. Geological Magazine, 130, 783-795. , NAGY, J., ELVERHOI, A., EIKELAND, T. A. & JOHANSEN, H. 1990. Structural development along the Billefjorden Fault Zone in the area between KjellstrOmdalen and Adventdalen/Sassendalen, central Spitsbergen. Polar Research, 8, 195 216. , SWENSON, E. & ANDRESEN, A. 1988. Structural development along the Lomfjorden Fault Zone in Agardhdalen, Spitsbergen: evidence of combined thick skinned and thin skinned tectonics (extended abstract). In: DALLMANN, W. K., ANDRESEN, A. & KRILL, A. (eds) Post Caledonian tectonic evolution of Svalbard. VI Annual I.S.G.S. - Meeting Oslo November 17/18, Intern Skriftserie, 54, Institutt for geologi, Universitet i Oslo, 19-20. -& 1992. Evidence of Mesozoic extension along the Lomfjorden Fault Zone, Agardhbukta (abstract). Norsk Geologisk Tidsskrift, 72, 136-137. HARLAND, W. B. 1939. Contribution to McCabe, L. H. 1939. Nivation and corrie erosion in West Spitsbergen. Geographical Journal, 94, 447-465. - - 1 9 4 1 . Geological notes on the Stubendorff Mountains, West Spitsbergen. Proceedings of the Royal Society of Edinburgh, B51, 119-129. - - 1 9 5 2 . The Cambridge Spitsbergen Expedition 1949. Geographical Journal, 118, 309-331,508-509. - - 1 9 5 3 . Contribution to the discussion of McWhae, J. R. H. "The major fault zone of central Vestspitsbergen". Quarterly Journal of the Geological Society of London, 108, 409-432. - - 1 9 5 6 . Contribution to the discussion of Sandford "The stratigraphy and structure of the Hecla Hock Formation and its relationship to a subjacent metamorphic complex in North East Land (Spitsbergen)". Quarterly Journal of the Geological Society of London, 112, 360-361. - - 1 9 5 6 . Tectonic facies, orientation, sequence, style and date. Geological Magazine, 93, 111-120. - - 1 9 5 9 . The Caledonian sequence in Ny Friesland, Spitsbergen. Quarterly Journal of the Geological Society of London, 114, 307-342. - - 1 9 5 9 . Palaeomagnetic investigation of Arctic rocks at Cambridge. Polar Record, 9, 556-561. -

-

-

-

-

-

-

-

-

-

,

- - 1 9 6 0 . The development of Hecla Hoek rocks in Spitsbergen. In: Report of the XXI International Geological Congress (Part XIX). International Geological Congress, Copenhagen, 1-16. - - 1 9 6 1 . An outline structural history of Spitsbergen. In: Geology of the Arctic, 1. University of Toronto Press, Toronto, 68-132. - - 1 9 6 3 . On Dating the British Tertiary Igneous Province. Geological Magazine, 100, 380-381. - - 1 9 6 4 . Critical evidence for a great infra-Cambrian glaciation. Geologische Rundschau, 54, 45-61. - - 1 9 6 4 . Evidence of Late Precambrian glaciation and its significance. In: NAIRN, A. E. M. (ed.) Problems of Palaeoclimatology. Wiley Interscience, 119-149 and 179-184. - - 1 9 6 5 . The tectonic evolution of the Arctic-North Atlantic region. In: BLACKErr, P. M. S., BULLARD,E. C. & RUNCORN, S. K. (eds) A Symposium on Continental Drift. Philosophical Transactions of the Royal Society of London, A258, 59-75. - - 1 9 6 6 . A hypothesis of continental drift tested against the history of Greenland and Spitsbergen. Cambridge Research, 2, 18-22. - - 1 9 6 7 a . Tectonic aspects of continental drift. Science Progress, 55, 1-14. - - 1 9 6 7 b . Early history of the North Atlantic Ocean and its Margins. Nature, 216, 464-466. - - 1 9 6 9 a . Mantle changes beneath the Barents Shelf. Transactions of the New York Academy of Sciences, Series II, 31, 25-41. - - 1 9 6 9 b . Contribution of Spitsbergen to understanding of tectonic evolution of North Atlantic region. In: North Atlantic Geology and Continental Drift. Memoirs of the American Association of Petroleum Geologists, 12, 817-851. - - 1 9 7 1 . Tectonic transpression in Caledonian Spitsbergen. Geological Magazine, 108, 27-42. - - 1 9 7 2 . Early Palaeozoic faults as margins of Arctic plates in Svalbard. In: Proceedings of the 24th International Geological Congress', Montreal, 3. International Geological Congress, Montreal, 230-237. - - 1 9 7 3 a . Mesozoic geology of Svalbard. In: PITCHER, M. (ed.) Arctic Geology. Memoirs of the American Association of Petroleum Geologists, 19, 135-148. - - 1 9 7 3 b . Tectonic evolution of the Barents Shelf and related plates. In: P~TCHER,M. (ed.) Arctic Geology. Memoirs of the American Association of Petroleum Geologists, 19, 599-608. - - 1 9 7 4 . The Precambrian-Cambrian boundary. In: HOLLAND,M. (ed.) Cambrian of the British Isles, Norden and Spitsbergen, Lower Paleozoic Rocks of the World, Part 2. John Wiley & Sons, London, 15-42. - - 1 9 7 5 a . Essay review - Palaeogene correlation in and around Svalbard. Geological Magazine, 112, 421-429. - - 1 9 7 5 b . Phanerozoic relative motions in North Atlantic Arctic Lands. In: Canada's

Continental Margins and Offshore Petroleum Exploration. Memoirs of the Canadian Society of Petroleum Geologists, 4, 235-256. - - 1 9 7 5 c . Alternative hypotheses for the pre-Carboniferous evolution of Svalbard. In: Symposium on Svalbard Geology, Oslo, 2 5 June 1975, Summary of Contributions, Norsk Polarinstitutt, 17. - - 1 9 7 5 a . The two geological time scales. Nature, 253, 505-507. - - 1 9 7 7 . International Stratigraphic Guide 1976: Essay Review. Geological Magazine, 114, 229-235. - - 1 9 7 8 . The Caledonides of Svalbard. In: Caledonian- Appalachian Orogen of the North Atlantic Region. Geological Survey of Canada Papers, 78-13, 3 II. - - 1 9 7 8 . A reconsideration of Late Precambrian stratigraphy of southern Spitsbergen. PolarJbrschung, 48, 44-61. - - 1 9 7 8 . Geochronologic scales. In: The Geologic Time Scale, American Association of Petroleum Geologists. Studies in Geology, Part 6, 9-32. - - 1 9 7 9 . A review of major faults in Svalbard. In: Proceedings of Conference VIIIAnalysis of Actual Fault Zones in Bedrock, 1-5 April 1979. Open File Reports of the United States Geological Survey, 79-1239, 157 180. - - 1 9 8 1 . Chronology of Earth's glacial and tectonic record. Journal of the Geological Society, London, 138, 197-203. - - 1 9 8 2 . Essay review - Arctic tectonics. Geological Magazine, 119, 619-631. ----1983. Proterozoic Glacial Record. In: MEDARIS, L. G. et al. (eds) Proterozoic Geology." Selected Papers from an International Proterozoic Symposium. Geological Society of America, Memoirs, 161,279-288. - - 1 9 8 5 . Caledonide Svalbard. ln: GEE, D. G. & STURT, B. A. (eds) The Caledonide Orogen- Scandinavia and Related Areas, Wiley, Chichester, 999-1016. - - 1 9 8 9 . Paleoclimatology. ln: Cowm, J. W. & BRASIER, M. D. (eds) The Precambrian-Cambrian Boundary. Oxford University Press, Oxford, 199-204. - - 1 9 9 2 . Stratigraphic regulation and guidance: a critique of current tendencies in stratigraphic codes and guides. Geological Society of America Bulletin, 104, 1231 1235. - - 1 9 9 5 a . Discussion of: "The West Spitsbergen Fold Belt: the result of Late Cretaceous-Paleocene Greenland-Svalbard convergence?" by N. Lyberis and G. M. Manby. Geological Journal, 30, 189-195. - - 1 9 9 5 b . The Ny Friesland Orogen, Spitsbergen: reply to Manby & Lyberis. Geological Magazine, 132, 354 356. , in press. Svalbard (Spitsbergen). In: MOORES, E. M. & FAIRBR1DGE,R. W. (eds) Encyclopedia of European and Asian Regional Geology. Encyclopedia of Earth Science Series. Chapman & Hall, London, 567-576. - - 1 9 9 6 . Proto-basement in Svalbard. Polar Research, 15, 000-000. -& BAYLY, M. B. 1958. Tectonic regimes. Geological Magazine, 95, 89-104. & BIDCOOD,D. E. T. 1959. Paleomagnetism in some Norwegian sparagmites and the Late Pre-Cambrian ice age. Nature, 184, 1860-1862. -& DOWDESWELL, E. K. (eds) 1988. Geological Evolution of the Barents Shelf Region. Graham & Trotman, London. -& GAYER, R. A. 1972. The Arctic Caledonides and earlier oceans. Geological Magazine, 109, 289-314.

-

-

REFERENCES & 1973. Poseidon, Proto-Atlantic and Iapetus - reply. Geological Magazine, 110, 375-376. & HEROD, K. N. 1975. Glaciations through time. In: WRIGHT, A. E. & MOSELEY, F. (eds) Ice Ages." Ancient and Modern, Steel House Press, Liverpool, 189-216. & HORSFIELD,W. T. 1974. West Spitsbergen Orogen. In: SPENCER, A. M. (ed.) Mesozoic-Cenozoic Orogenic Belts, Data for Orogenic Studies. Special Publications of the Geological Society, London, 4, 747-755. -& MASSON-SMITH, D. 1962. Cambridge survey of central Vestspitsbergen. Geographical Journal, 128, 58-70 + 1 : 125,000 topographical map. & WILSON, C. B. 1956. The Hecla Hoek succession in Ny Friesland, Spitsbergen. Geological Magazine, 93, 256-286. & WRIGHT, N. J. R. 1979. Alternative hypothesis for the pre-Carboniferous evolution of Svalbard. Norsk Polarinstitutt Skrifter, 167, 89-117. , ARMSTRONG, R. L., COX, A., V, CRAIG, L. E., SMITH, A. G. & SMITH, D. G. 1990. A Geologic Time Scale 1989, Cambridge University Press, Cambridge. , CUTBILL,J. L., FRIEND, P. F., GOBBETT,D. J., HOLLIDAY,D. W., MATON, P. I., PARKER, J. R. & WALLIS, R. H. 1974. The Billefjorden Fault Zone, Spitsbergen: the long history of a major tectonic lineament. Norsk Polarinstitutt Skrifter, 161, 1-72. , GASKELL,B. A., HEAFFORD, A. P., LIND, E. K. & PERKINS,P. J. 1984. Outline of Arctic post-Silurian continental displacements. In: SPENCER, A. M. et al. (eds) Petroleum Geology of the North European Margin. Graham & Trotman, London, 137-148. - - , HAMBREY,M. J. ~r WADDAMS, P. 1993. The Vendian geology of Svalbard. Norsk Polarinstitutt Skrifter, 193, 1-130. , HEROD, K. N. & KRINSLEY,D. H. 1966. The definition and identification of tills and tillites. Earth Science Reviews, 2, 225-256. , HORSFIELD, W. T., MANBY, G. M. & MORRIS, A. P. 1979. An outline of the pre-Carboniferous stratigraphy of western Central Spitsbergen. Norsk Polarinstitutt Skrifter, 167, 119-144. , MANN, A. & TOWNSEND, C. 1988. Deformation of anhydrite-gypsum rocks in central Spitsbergen. Geological Magazine, 125, 103-116. , PERKINS,P. J. & SMITH,M. P. 1988. Cambrian through Devonian stratigraphy and tectonic development of the western Barents Shelf. In: HARLAND, W. B. & DOWDESWELL, E. K. (eds) Geological Evolution of the Barents Shelf Region. Graham & Trotman, London, 73-88. , PICKTON, C. A. G. & WRIGHT, N. J. R. 1976. Some coal-bearing strata in Svalbard. Norsk Polarinstitutt Skrifter, 164, 7-28. , SCOTT, R. A., AUCKLAND, K. A. • SNAPE, I. 1992. The Ny Friesland Orogen, Spitsbergen. Geological Magazine, 129, 679-708. , SMITH, A. G. & WILCOCK, A. (eds) 1964. The Phanerozoic Time-scale. Geological Society, London, Special Publications, 1. , WALL/S, R. H. & GAYER, R. A. 1966. A revision of the lower Hecla Hoek succession in central north Spitsbergen and correlation elsewhere. Geological Magazine, 103, 70-97. , AGER, D. V. 8L 15 OTHERS 1972. A concise guide to stratigraphical procedure. Journal of the Geological Society, London, 128, 295-305. HARRIS, A. L., BALDWIN,C. T., BRADBURY,H. J., JOHNSON,H. D. & SMITH,R. A. 1978. Ensialic basin sedimentation: the Dalradian Supergroup. In: BOWLS, D. R. & LEAKE, B. E. (eds) Crustal Evolution in Northwestern Britain and Adjacent Regions. Geological Journal, Special Issue, 115-138. HARTZ, E. & ANDRESEN, A. 1995. Caledonian sole thrust of central East Greenland: a crustal-scale Devonian extensional detachment. Geology, 23, 637-640. HATLEBERG, E. W. & CLARK, D. L. 1984. Lower Triassic conodonts and biofacies interpretations: Nepal and Svalbard. Geologica et Paleontologica, 18, 101-125. HAY, W. W., SHAW, C. A. & WOLD, C. N. 1989. Mass-balanced paleogeographic reconstructions. Geologische Rundschau, 78, 207. HEAD, M. J. 1984. A palynological investigation of Tertiary strata at RENARDODDEN, W. Spitsbergen (abstract). Sixth International Palynological Conference, Calgary. HEAFEORD, A. P. 1988. Carboniferous through Triassic stratigraphy of the Barents Shelf. In: HARLAND,W. B. ~6 DOWDESWELL,E. K. (eds) Geological Evolution of the Barents Shelf Region. Graham & Trotman, London, 89-106. HEAFEORD, A. P. 1992. The geology of Paleozoic hydrocarbonates in the eastern European USSR and their relevance to Barents shelf. In: VOREEN,T. O. et al. (eds) Arctic Geology and Petroleum Potential. NPF Special Publications, 2, 261-271. & KELLY, S. R. A. 1988. Carboniferous through Cretaceous Panarctic Tectonic Events. In: HARLAND,W. B. & DOWDESWELL,E. K. (eds) Geological Evolution of the Barents Shelf Region. Graham & Trotman, London, 19-32. HEDBERG, H. D. (ed.) 1976. International Stratighraphic Guide. New York, Wiley. HEER, O. 1866. On the fossil plants discovered in Spitsbergen by A. E. Nordenski61d and C. W. Blomstrand. Kungliga Svenska Vetenskapsakademiens OJvers..4rg., 23, 149-155 [in Swedish]. - - 1 8 6 8 . Die Fossile Flora der Polarldnder enthaltend die in Nordgr6nland, auf der Melville Insel, in Banksland, am Mackenzie, in Island und in Spitzbergen entdeckten fossilen Pflanzen. Zurich. - - 1 8 6 8 . On the Miocene flora of the polar regions. Geological Magazine, 5, 273-280. - - 1 8 7 0 . Die miocene Flora und Fauna Spitzbergens. Mit einem Anhang fiber die diluvialen Ablagerungen Spitzbergens. Kungliga Svenska Vetenskapsakademiens Handlingar, 8, 1-98. - - 1 8 7 1 a . Fossile Flora der Bdren-Insel. Enthaltend die Beschreibung yon den Herrn A. E. Nordenskidld und A. J. Malmgren im Sommer 1868 der dort gefundenen Pflanzen. Kungliga Svenska Vetenskapsakademiens Handlingar, 9, 1-51. - - - 1 8 7 1 b . Die mioc~ine Flora von Spitzbergen. Gaea, 7, 91-98. - - 1 8 7 2 . On the Carboniferous flora of Bear Island. Quarterly Journal of the Geological Society of London, 28, 161 169. - - 1 8 7 4 a . Uebersicht der miocenen Flora der arktischen Zone. Zurich.

-

-

-

-

-

-

-

-

-

-

-

-

491

- - 1 8 7 4 b . Beitrdge zur Steinkohlen-Flora der arctischen Zone. I. Steinkohlen-Pflanzen aus der Klaas Billen-bai in Spitzbergen. Kungliga Svenska Vetenskapsakademiens Handlingar, 12, 1-7. - - 1 8 7 4 c . Die Kreideflora der arctischen Zone, gegrfindet auf die yon den schwedischen Expedition yon 1870 und 1872 in Grdnland und Spitzbergen gesammelten Pflanzen. Kungliga Svenska Vetenskapsakademiens Handlingar, 12. - - 1 8 7 4 d . [Remarks on the fossil plants discovered by the Swedish polar expedition of 1872-73]. Kungliga Svenska Vetenskapsakademiens O'fvers. ,4rg., 31, 25-32. - - 1 8 7 6 . Beitrdge zur fossilen Flora Spitzbergens. Gegrfindet auf die Sammlungen der schwedischen Expedition vom Jahre 1872 auf 1873. Mit einen Anhang: Obersicht der Geologie des Eisfjordes und des Bellsundes von Prof. A. E. Nordenskidld. Kungliga Svenska Vetenskapsakademiens Handlingar, 14. - - 1 8 7 7 . Die Fossile Flora der Polarldnde, 4, Zurich. - - 1 8 8 0 . Flora fossilis arctica. Die Fossile Flora de Polarlande, 6. - - 1 8 8 6 - 1 8 8 0 . Die Fossile Flora der Polarldnder. Friedrich Schulthess, Zurich. HEEZEN, B. C. & EWlNG, M. 1961. The mid-oceanic ridge and its extension through the Arctic Basin. Geology of the Arctic, 1 University of Toronto Press, 622-642. HEiYrz, A. 1926. Bl~skjell p~t Spitsbergen. Norsk Geologiske Tidsskrift, 9, 7-36. - - 1 9 2 8 . Einige Bemerkungen fiber den Panzerbau bei Homosteus und Heterosteus. Skrifter udgivne af Videnskabsselskabet i Kristiania. Mat.-Naturv 1928, 1-12. - - 1 9 2 9 . Die Downtonischen und Devonischen Vertebraten yon Spitzbergen. 11. Acanthaspida. Skrifter om Svalbard og Ishavet 22. III Acanthaspida. Nachtrag. Skrifter om Svalbard og Ishavet, 23. - - 1 9 3 5 . Holonema-Reste aus dem Devon Spitzbergens. Norsk Geologisk Tidsskrift, 15, 115-122. - - 1 9 3 7 . Die Downtonischen und Devonischen Vertebrater von Spitzbergen. VI. Lunaspis-arten dem Devon Spitzbergens. Skrifter om Svalbard og Ishavet, 72, 1-23. - - 1 9 5 3 . [Some observations about glacial retreat in Hornsund, Spitsbergen]. Norsk Geologiske Tidsskrift, 31, 7-36. - - 1 9 6 2 . New investigations on the structure of Arctolepis from the Devonian of Spitsbergen (the Downtonian and Devonian vertebrates of Spitsbergen XII). Norsk Polarinstitutt Arbok 1961, 23-40. -& SIGGERUD,T. 1965. A note on the stratigraphy of Goldschmidtfjella, Oscar II Land. Norsk Polarinstitutt .4rbok 1963, 251-258. , WINSNES, T. S. & HEINTZ, N. 1961. Aspects of the geology of Svalbard. Norsk Polarinstitutt Meddelelser, 87. HEINTZ, N. 1960. The Downtonian and Devonian vertebrates of Spitsbergen. X. Two species of the genus Pteraspis from the Wood Bay series in Spitsbergen. Norsk Polarinstitutt Skrifter, 117, 1-13. - - 1 9 6 2 . The Downtonian and Devonian vertebrates of Spitsbergen. XI. Gigantaspis - a new genus of fam. Pteraspidae from Spitsbergen. A preliminary note. Norsk Polarinstitutt ~lrbok 1960, 22-27. - - 1 9 6 2 . Geological excursion to Svalbard in connection with the 21st International Geological Congress in Norden 1960. Norsk Polarinstitutt flrbok 1960, 98-106. - - 1 9 6 3 . Dinosaur footprints and polar-wandering. Norsk Polarinstitutt Arbok 1962, 35-43. --1964. Mesozoiske oglefunn fra Norge og Svalbard. Norsk Polarinstitutt Meddelelser, 91. - - 1 9 6 5 . Doryaspis nathorsi ell eiendomnelih pteraspidomorph fra Svalbards Devon (abstract). Geologi (Helsinki), 17, 133. - - 1 9 6 8 . The pteraspid Lyktaspia n.g. from the Devonian of Vestspitsbergen. In: ~RVIG, T. (ed.) Current Problems of Lower Vertebrate Phylogeny, 73-80. Stockholm: Proceedings of the Fourth Nobel Symposium, 73-80. - - 1 9 7 2 . The thelodont Sigurdis lata n.g., n. sp. from the Lower Devonian at Sigurdfjellet, Spitsbergen. Norsk Polarinstitutt Arbok 1970, 112-116. HELLAND-HANSEN,W. 1990. Sedimentation in Paleogene foreland basin, Spitsbergen. American Association of Petroleum Geologists Bulletin, 74, 260-272. , HELLE, H. B. & SUNDE, K. 1994. Seismic modelling of Tertiary sandstone clinothems, Spitsbergen. Basin Research, 6, 181-191. HELLEM, T. 1987. Miseryfjellet Formation. In: MORK, A. (ed.) Geological Excursion Guide to Bjornoya. IKU, Trondheim. -& WORSLEY, D. 1978. An outcrop of the Kapp Starostin Formation at Austjokeltinden, Sorkapplandet. Norsk Polarinstitutt Arbok 1977, 340-343. HELLMAN, F. J., GEE, D. G., JOHANSSON,A. & WITT-N1LsSON,P. 1997. Single-zircon Pb-evaporation geochronlogy constraints basement-cover relationships in the Lower Hecla Hoek of northern Ny Friesland, Svalbard. Chemical Geology, 137, 117-134. HELOVUORI, O. 1983. [On coal investigations of Gipsdalen]. Geologi, 35 Vuosikerta [Annual volume], 77-82, HENRIKSEN, N. 1978. East Greenland Caledonian fold belt. In: CaledonianAppalachian Orogen of the North Atlantic Region. Geological Survey of Canada Papers, 78-13, 105-109. -& HIGGINS,A. K. 1976. East Greenland Caledonian Fold Belt. In: ESCHER,A. & WATT, W. S. (eds) Geology of Greenland. Geological Survey of Greenland, 1

8

2

-

2

4

6

.

, FRIDERICHSEN,J. D., STRACHAN, R. A., SOPER, N. J. & HIGGINS, A. K. 1989. Caledonian and pre-Caledonian geology of the region between Grandjean Fjord and Bessel Fjord (75~176 North-East Greenland. Rapport, Gronlands Geologiske Undersogelse, 145, 90-97. HEQUETTE, A. 1992. Post-glacial relative sea-level history of northwestern Spitsbergen, Svalbard: alternative interpretation. Geological Society of America Bulletin, 104, 1059-1064. HERITSCH, F. 1929. Line Caninia aus dem Karbon des De Geer-Berges im EisfjordGebiet auf Spitzbergen. Skr~ter om Svalbard og Ishavet, 24, 1-21.

492

REFERENCES

- - 1 9 3 9 . Die Korallen des Jungpal~iozoikums von Spitzbergen. Arkiv fur Zoologic, 31, 1-138. HERMAN, A. B. & SI'IC~R, R. A. 1996. Palaeobotanical evidence for a warm Cretaceous Arctic Ocean. Nature, 380, 330-333. HEUGLIN,T. 1874. Reisen nach dem Nordpolarmeer in den Jahren 1870 und 1871. Dritter theil: Beitriige zur Fauna, Flora und Geologic yon Spitzbergen und Novaya Zemlya. Braunschweig. HINDE, G. J. 1888. On the chert and siliceous schists of the Permo-Carboniferous strata of Spitsbergen, and on the characters of the sponges therefrom, which have been described by Dr. E. von Dunikowski. Geological Magazine, 5, 241-251. H~ORTH, F. 1912. Om Spitsbergens kulforekomster [On the coal deposits of Spitsbergen]. Teknisk Ukeblad, 30, 135-137. HrRAJIMA, T. 1990. Action records of The Svalbard Geological Expedition, Kyoto University, Japan, 1983. In: TATSUMI,T. (ed.) The Japanese Scientific Expeditions to Svalbard 1983-1988. Kyoikusha, Tokyo, 115-124. , BANNO, S., HIROI, Y. & OHTA, Y. 1988. Phase petrology of eclogites and related rocks from the Motalafjella high-pressure metamorphic complex in Spitsbergen (Arctic Ocean) and its significance. Lithos, 22, 75-97. , HIRO~, Y. & OHTA, Y. 1984. Lawsonite and pumpellyite from the Vestg6tabreen Formation in Spitsbergen. Norsk Geologisk Tidsskrift, 64, 267-274. HISDAL, V. 1985. Geography of Svalbard. Polarhhndbok No. 2, Norsk Polarinstitutt, Oslo. HJELLE, A. 1962. Contribution to the geology of the Heela Hock Formation in Nordenski61d Land, Vestspitsbergen. Norsk Polarinstitutt Arbok 1961, 83-95. --1965. On the geology of the upper Grusdievbreen area, Olav V Land, Vestspitsbergen. Norsk Polarinstitutt Arbok 1963, 81-88. - - 1 9 6 6 . The composition of some granitic rocks from Svalbard. Norsk Polarinstitutt Arbok 1965, 7-30. - - 1 9 6 8 . [Recent investigations in the meta-supracrustal/migmatite complex in northwest Svalbard]. Geologiska Ftreningens i Stockholm Ftrhandlingar, 90, 460. 1969. Stratigraphical correlation of Hecla Hoek successions north and south of Bellsund. Norsk Polarinstitutt .4rbok 1967, 46-51. - - 1 9 6 9 . Comparison of chemical and modal analyses of granitic rocks from Svalbard. Norsk Polarinstitutt Arbok 1967, 230-232. 1970. [change of name in Svalbard]. Norsk Polarinstitutt flrbok 1968, 79-80. - - 1 9 7 8 . A preliminary report on the geology of Sjuoyane. Norsk Polarinstitutt ~lrbok 1977, 337-340. - - 1 9 7 8 . An outline of the Pre-Carboniferous geology of Nordaustlandet. Polarforschung, 48, 62-77. - - 1 9 7 9 . Aspects of the geology of northwest Spitsbergen. Norsk Polarinstitutt Skrifter, 167, 37-62. - - 1 9 8 8 . Tertiary structures in western Nordenskitld Land. In: DALLMANN,W. K. OHTA, Y. & ANDRESEN (eds) Tertiary Tectonics ofSvalbard. Norsk Polarinstitutt, Report Series, 46, 29-31. - - 1 9 9 3 . Geology of Svalbard. Polarhandbok, No. 7, Norsk Polarinstitutt, Oslo. -& LAURITZEN, O. 1982. Geological Map of Svalbard. 1:500000. Sheet 3G, Spitsbergen Northern part. Norsk Polarinstitutt Skrifter 154C. - & OHTA, Y. 1974. Contribution to the geology of north western Spitsbergen. Norsk Polarinstitutt Skrifter, 158, 1-107. , LAURITZEN, O., SALVIGSEN, O. & WINSNES, T. S. 1986. Geological Map of Svalbard: 1:100 000. B10G Van Miienfjorden. Norsk Polarinstitutt Temakart, 2. , OHTA, Y., THIEDIG,F., PtEPJOHN, K., DALLMANN,W. K. & SVALmGSEN,O. 1994. Geological Map of Svalbard, 1: 100000. Sheet A7G Kongsfjorden, preliminary edition. Norsk Polarinstitutt. --, -& WINSNES, T. S. 1978. The geology of northeastern Svalbard. Norsk Polarinstitutt ~lrbok 1977, 7 24. --, -& 1979. Hecla Hock rocks of Oscar II Land and Prins Karls Forland, Svalbard. Norsk Polarinstitutt Skrifter, 167, 145-169. HJORT, C., ADRIELSSON,L. J., MANGERUD, J. & SALVIGSEN,O. 1992. Mytilus edulis on eastern Svalbard- dating the Holocene Atlantic water influx maximum. LUNDQUA Report, 35, 171-175. , MANGERUD, J., ADRIELSSON,t . , BONDEVIK,S., LANDVIK,J. Y. & SALVIGSEN,0. 1995. Radiocarbon dated common mussels Mytilus edulis from eastern Svalbard and the Holocene marine climatic optimum. Polar Research, 14, 239-243. HOCHULI, P. A., COLIN, J. P. & VIGRAN, J. O. 1989. Triassic biostratigraphy of the Barents Sea area. In: COLLINSON, J. D. (ed.) Correlation in Hydrocarbon Exploration. Graham & Trotman, London, 131-153. HODGKINS,R. & DOWDESWELL,J. A. 1994. Tectonic processes in Svalbard tidewater glacier surges: evidence from structural glaciology. Journal of Glaciology, 40, 553-560. --, TRANTER, M. & DOWDESWELL, J. A. 1995. Hydrochemical interpretation of meltwater routing through a High Arctic (cold-based) glacier. International Association of Hydrological Sciences Series, 228, 387-394. HOEG, O. A. 1926. Contributions to the natural history of the Hope Island. Fossil plants. Resultater Norske Spitzbergenekspeditioner, 1, 32-33. - - 1 9 4 2 . The Downtonian and Devonian flora of Spitsbergen. Skrifter om Svalbard og Ishavet, 83, 1-229. - - 1 9 5 6 . The present and past vegetation of Spitsbergen. Proceedings of the Linnean Society of London, 166, 144-149. - - 1 9 7 3 . Pertica sp. in the Devonian of Mimerdalen, Spitsbergen. Norsk Geologisk Tidsskrift, 53, 85-86. HOEL, A. 1909. [Geological observations made on the Spitsbergen expeditions in 1906 and 1907]. Norsk Geologisk Tidsskrift, 1, 1-28. - - 1 9 1 2 . Rapport sur ses traveaux au cour de l'exptdition Isachsen au Spitsberg, en 1909-1910. Skrifter udgivne af Videnskabsselskabet i Kristiania. Mat.-Naturv, 15, 81-85. - - 1 9 1 4 . Nouvelles observations sur le district volcanique du Spitsberg du Nord. Skrifter udgivne af Videnskabsselskabet i Kristiania. Mat.-Naturv, K1, 1-33.

- - 1 9 1 4 . Exploration du Nord-Ouest du Spitsberg entreprise sous les auspices de S.A.S. le Prince de Monaco par la Mission Isachsen. Troisi~me Partie. Rtsultats des Campagnes Scientifiques, Monaco, Fasc. 42. - - 1 9 1 6 . [The Arctic Coal Co.'s coalfields in Spitsbergen]. Tidsskrft. Bergv. Aarg., 4, 78-84. - - 1 9 1 6 . Observations sur la vitesse d'ecoulement et sur l'ablation du glacier Lillehook au Spitsberg 1907-1912. Kristiania Videuskepet Skrifter 1. Math-natur. K1. - - 1 9 2 0 . [The coal and ore deposits of Spitsbergen, their economic importance and distribution between the different nations]. Norsk Geologisk Tidsskrift, 5, 417-419. - - 1 9 2 2 a . [The coal deposits of Spitsbergen and Bear Island and their importance to our country]. Teknisk Ukeblad 1922, 285-287. - - 1 9 2 2 b . [The coals from Spitsbergen and Bjornoya and the fuel supply of Norway]. Teknisk Ukeblad 1922, 462-466. - - 1 9 2 2 c . A burning coal seam at Mt. Pyramide, Spitsbergen. In: Resultater an de Norske stas undersokelse. Spitsbergen ekspedit, 1(3). Skrifter om Svalbard og Ishavet. - - 1 9 2 4 . The coal-fields of Svalbard (Spitsbergen and Bear Island). In: Transactions of the First Worm Power Conference, 1, London, 1008-1040. - - 1 9 2 5 . The coal deposits and coal mining of Svalbard (Spitsbergen and Bear Island). Skrifter om Svalbard og Ishavet, 6, 1-92. - - 1 9 2 9 . The Norwegian Svalbard Expeditions 1906-1926. In: HOEL, A. (ed.) Resultates av de Norske Statsunderstottede Spitbergenekspeditioner, 1, 104. - - 1 9 3 8 . Coal mining in Svalbard. Polar Record, 2, 74-85. - - 1 9 4 4 . The Survey of Bjornoya (Bear Island) 1922-1931. Skrifter om Svalbard og Ishavet, 8 6 . - - 1 9 6 6 . Svalbard. Svalbard's historic 1596-1965, Vol. 1-3. Sverre Kildahls, Oslo. -& HOLTEDAHL,O. 1911. Les nappes de lave, les volcans et les sources thermales dans les environs de la Baie Wood au Spitsberg. Skrifter udgivne af Videnskabsselskabet i Kristiania. Mat.-Naturv, 8. - & ORVIN, A. K. 1937. Das Festungsprofil auf Spitzbergen. Karbon-Kreide. Part I. Vermessungsresultate. Skrifter om Svalbard og Ishavet, 18, 1-59. HOVFMAN, P. 1991. Did the breakout of Laurentia turn Gondwana Land inside-out? Science, 252, 1409-1412. HOFMANN, W. 1968. Geobotanische Untersuchungen in Sfidost-Spitzbergen 1960. Franz Steiner, Wiesbaden. HtGBOM, B. 1911. [Contributions to the Quaternary geology of the Isfjorden area]. Geologiska Ftreningens Stockholm Ftrhandlingar, 33. - - 1913. The coal resources of Spitsbergen. In: Vol. 3. The Coal Resources of the World. International Geological Congress. 12th Session, Toronto, Canada, 1141-1147. - - 1 9 1 3 . Om Spetsbergens mytilorstid. Geologiska Ftreningens i Ftrhandlingar, 35. - - 1 9 1 4 . Uber die geologische Bedeutung des Frostes. Bulletin of the Geological Institution of the University of Uppsala, 12, 257-389. HOLDSWORTH,R. E. & STRACaAN, R. A. 1991. Interlinked system of ductile strike slip and thrusting formed by Caledonian sinistral transpression in northeastern Greenland. Geology, 19, 510-513. HOLLAND, C. H. (ed.) 1974. Cambrian of the British Isles, Norden and Spitsbergen. Lower Palaeozoic Rocks of the World, Part 2. John Wiley & Sons, London. HOLLAND, M. F. W. 1961. The geology of certain parts of eastern Spitsbergen. Norsk Polarinstitutt Skrifter, 122, 1-44. HOLL1DAY, D. W. 1966. Nodular gypsum and anhydrite rocks in the Billefjorden region, Spitsbergen. Norsk Polarinstitutt ,4rbok 1965, 65-74. --1967. Secondary gypsum in Middle Carboniferous rocks of Spitsbergen. Geological Magazine, 104, 171-177. - - 1 9 6 8 a . Basal sediments of the Nordenskitldbreen Formation (Middle Carboniferous) on the southwest coast of Broggerhalvoya, Spitsbergen. Norsk Polarinstitutt Arbok 1966, 99-104. - - 1 9 6 8 b . Early diagenesis in Middle Carboniferous nodular anhydrite of Spitsbergen. Proceedings of the Yorkshire Geological Society, 36, 277-292. - - 1 9 7 3 . Early diagenesis in nodular anhydrite rocks. Transactions of the Institution of Mining and Metallurgy, Section B Applied Earth Science, 82, B81-B84. -& CUTBILL,J. L. 1972. The Ebbadalen Formation (Carboniferous), Spitsbergen. Proceedings of the Yorkshire Geological Society, 39, 1-32. HOLMES, A. 1918. The basaltic rocks of the Arctic region. Mineralogical Magazine, 18, 180-223. - & HARWOOD, H. F. 1917. The basaltic rocks of Spitsbergen and Franz-Joseph Land, with conclusions regarding the Brito-Arctic Tertiary petrographic province. Nature, 99, 97-98. HOLMSEN, G. 1911a. [The nature and history of Spitsbergen]. Kristiania. --191lb. [Report on a geological expedition to Spitsbergen in 1909]. Bergens Museums Aarbog 1911, 1-76. HOLTEDAHL, 0. 1911. Zur kenntnis der Karbonablagerungen des westlichen Spitzbergens. L Eine fauna der Moskauer Stufe. Skrifter udgivne af Videnskabsselskabet i Kristiania. Mat.-Naturv, 10. - - 1 9 1 2 . Rapport sur ses traveaux au cour de l'exptdition Isaclisen au Spitsberg, en 1909-1910. In: ISACHS~N, G. (ed.) Rapport sur l'expddition Isachsen au Spitsberg 1909-1910. Skrifter udgivne af Videnskabsselskabet i Kristiania. Mat.-Naturv, 14, 86-88. - - 1 9 1 3 . Zur kenntnis der Karbonablagerungen des westlichen Spitzbergens. IL Allgemeine stratigraphische und tektonische Beobachtungen. Skrifter udgivne af Videnskabsselskabet i Kristiania. Mat.-Naturv, 23. - - 1 9 1 4 a . New features in the geology of northwestern Spitzbergen. American Journal of Science, 37, 415-424. 1914b. On the Old Red Sandstone Series of northwestern Spitzbergen. In: Congress Report, XIIth Session. International Geological Congress, Canada, 707-712. - - 1 9 1 8 . Notes on the Ordovician fossils from Bear Island collected during the Swedish expedition of 1898 and 1899. Norsk Geologisk Tidsskrift, 5, 121.

REFERENCES - - 1 9 1 9 . [On the distribution of land and sea in the North-Atlantic-Arctic region in Paleozoic time]. Naturen. Aarg., 43, 73-87 and 119-130. - - 1 9 1 9 . On the Paleozoic formations of Finmarken in northern Norway. American Journal of Science, 197, 85-107. - - 1 9 2 0 . Paleogeography and diastrophism in the Atlantic-Arctic region during Paleozoic time. American Journal of Science, 49, 1-25. - - 1 9 2 0 . Notes on the Ordovician fossils from Bear Island collected during the Swedish Expeditions of 1898 and 1899. Norsk Geologisk Tidsskrift, 5, 79-94. - - 1 9 2 0 . On the Paleozoic series of Bear Island, especially the Hecla Hoek System. Norsk Geologisk Tidsskrift, 5, 121-148. - - 1 9 2 0 . [The geology of Spitsbergen and Bjornoya]. Naturen. Aarg., 44, 288 307. - - 1 9 2 5 . Some points of structural resemblance between Spitsbergen and Great Britain, and between Europe and North America. Avhandlingar utgitt av det Norske Videnskapsakademi i Oslo, Mat.-Naturvid. Klasse, 4, 1-20. - - 1 9 2 5 . A 'pipe-rock' in the Upper Carboniferous of Bear Island. Norsk Geologisk Tidsskrift, 8, 270-280. - - 1 9 2 6 . Notes on the geology of northwestern Spitsbergen. Skrifter om Svalbard og Ishavet, 8, 1-25. - - 1 9 2 6 . Tectonics of the Arctic regions. Pan-American Geology, 46, 257~72. - - 1 9 2 9 . Some remarkable features of the sub-marine relief on the north coast of the Varanger Peninsula, northern Norway. Avhandlingar utgitt av det Norske Videnskapsakademi I Oslo, 12. - - 1 9 3 0 . Geologische Karte der Arktis mit angrenzenden Gebieten. In: PERTHUS, J. (ed.) Arktis, 3, 49-60. Gotha. - - 1 9 3 1 . Some general structural features of the Arctic and adjacent regions (abstract). Proceedings of the Geological Society of London, 87, CVII-VIII. - - 1 9 3 1 . Additional observations on the rock formations of Finmarken, northern Norway. Norsk Geologisk Tidsskrift, 11, 241-279. - - 1 9 3 2 . Einige Hauptlinien im geologischen Bau des nordatlantisch-arktischen Gebietes. Zeitschrift der Deutschen Geologischen Gesellschaft 1932, 176. - - 1 9 3 6 . On fault lines indicated by the submarine relief in the shelf area west of Spitsbergen. Norsk Geologisk Tidsskrift, 6, 214-221. HOLZAPFEL, P. 1892. Petrefacten von Spitzbergen und Bfiren-Eiland. In: CREMER, L. (ed.) Ein Ausflug nach Spitzbergen. Berlin, 74-80. HOOKE, LEB., R. & ELVERHOI, A. 1996. Sediment flux from a fjord during glacial periods, Isfjorden, Spitsbergen. In: SOLHEIM,A., RtIS, F., ELVERHOI,A., FALEIDE, J. I., JENSEN, L. N. & CLOETINGH, S. (eds) Global and Planetary Change, 12, 237-250. HOPPE, G. 1981. Glacial traces on the island of Hopen, Svalbard: a correction. Geografiske Annalen, 63A, 67-68. , SCHYTT, V., H~.GGBLOM, A. & OSTERHOLM, A. 1969. The glacial history of Hopen. Geografiske Annalen, 514, 185-192. HORN, G. 1928. Beitrdge zur Kenntnis der Kohle yon Svalbard (Spitzbergen und der Bgireninsel). Skrifter om Svalbard og Ishavet, 17, 1-60. - - 1 9 2 9 a . l[lber gagatartige Kohle aus Spitzbergen. Norsk GeoIogisk Tidsskrift, 10, 213~15. - - 1 9 2 9 b . [Petrographic examination of Svalbard coal]. Norsk Geologisk Tidsskrift, 10, 466-468. - - 1 9 3 0 . Die Kohlenvorkommen Svalbards. Geologische Rundschau, 21, 349-351. - - 1 9 3 2 . Some geological results of the Norwegian expedition to Franz Josef Land 1930. Norsk Geologisk Tidsskrift, I1,482-489. - - 1 9 3 5 . Petrified wood from a Tertiary coal-seam in Spitsbergen. Norsk Geologisk Tidsskrift, 14, 312-315. - - 1 9 4 1 . Petrology of a Middle Devonian cannel coal from Spitsbergen. Norsk Geologisk Tidsskrift, 21, 13-18. -& ORVIN, A. K. 1928. Geology of Bear Island with special reference to the coal deposits, and with an account of the history of the island. Skrifter om Svalbard og Ishavet, 15. HORNER, L. 1860. Notes on rock-specimens from Spitzbergen, collected by Capt. Parry and Lieut. Foster. Quarterly Journal of the Geological Society of London, 16, 442-444. HORODYSKt, B. & KOSSOBUDZKI,K. 1988. [Geomorphological map of the western part of Nordenski61d Land/western Spitsbergen. Scale 1:75000]. In: JAHN, A., PEREYMA, J. & SZCZEPANKIEWlCZ-SZMYRKA,A. (eds) X V Sympozjum Polarne. Start obecny i wybrane problemy polskich badan polarnyeh, Wroelaw 19-21 May 1988. Wydawnictwo Uniwersytetu Wroclawskiego, Warsaw, 57-60. HORSFIELD, W. T. 1970. Cambridge Spitsbergen Expedition 1969. Polar Record, 15, 331. - - 1 9 7 2 . Glaucophane schists of Caledonian age from Spitsbergen. Geological Magazine, 109, 29-36. --t973. Half-moon oolites from the Hecla Hoek of Nordenski61d Land, Spitsbergen. Norsk Polarinstitutt Arbok 1971, 55-58. & MATON, P. I. 1970. Transform faulting along the De Geer Line. Nature, 226, 256 257. HOUNSLOW, M. W., MORK, A., PEERS, C. & WEITSCHAT, W. 1996. Boreal Lower Triassic Magnetostratigraphy from Deltadalen, Central Svalbard. Albertiana 17 May 1996, 3-9. How, O. 1990. Shallow Drilling Bjornoya West 1989. Appendix Volume 4 - Core Photographs. IKU, Report 21.3465. HOWELLS, K 1967. Cambridge Spitsbergen Expedition 1966. Polar Record, 13, 458-459. - - 1 9 6 7 . Land Gravity Measurements in Spitsbergen. U.K. contribution to the Upper Mantle Project, progress report. Royal Society, London. MASSON-SMITH, D. & MATON, P. I. 1977. Some rock and formation densities from Svalbard. Norsk Polarinstitutt Arbok 1975, 53-67. HUGHES, N. F. 1989. Fossils as information: new recording and stratal teachings, Cambridge University Press. -

-

,

493

- - 1 9 8 9 . W. B. Harland. Geological Magazine, 126, 463-468. - - 1 9 9 4 . The Enigma of AngiosTerm Origins. Cambridge University Press. & PLAYEORD,G. 1961. Palynological reconnaissance of the Lower Carboniferous of Spitsbergen. Micropaleontology, 7, 27-44. , HARLAND, W. B. & SMITH, D. G. 1976. Preservation and abundance of palynomorphs in Svalbard. Geological Magazine, 113, 233-240. HuanEs, T. J. 1992. Theoretical calving rates from glaciers along ice walls grounded in water of variable depths. Journal of Glaciology, 38, 282-294. , DENTON, G. H. & GROSSWALD,H. G. 1977. Was there a Late-Wurm Arctic Ice Sheet? Nature, 266, 596-602. HULKE, J. W. 1873. Memorandum on some fossil vertebrates remains collected by the Swedish expeditions to Spitzbergen in 1864 and 1868. Bih. Kungliga Svenska Vetenskapsakademiens Handlinger, 1, 1 11. Uppsala & Stockholm. HURCEWITZ, H. 1982. Permian sponges from brachiopod cherts at Hornsund, Spitsbergen. Acta Palaeontologica Polonica, 27, 85-114. HURST, J. M., MCKERROW, W. S., SOPER, N. J. & SURLYK, F. 1983. The relationship between Caledonian nappe tectonics and turbidite deposition in North Greenland. Journal of ttte Geological Society, London, 140, 123-132. HUTCHINS, P. F. 1952. History of Fieldwork. In: GEE, E. R., HARLAND, W. B. & MCWHAE (eds) q.v. - - 1 9 6 2 . Authigenic minerals in Carboniferous sediments from central Vestspitsbergen. Geological Magazine, 99, 63-68. HUTTON, D. H. W. 1987. Strike-slip terranes and a model for the evolution of the British and Irish Caledonides. Geological Magazine, 124, 405 425. , DEMPSTER, T. J., BROWN, P. E. & BECKER, S. D. 1990. A new mechanism of granite emplacement: intrusion in active extensional shear zones. Nature, 343, 452-455. HUXLEY, J. S. & ODELL, N. E. 1924. Notes on surface markings in Spitsbergen. Geographical Journal, 63, 207-229. HVOSLEF, S., DYPVIK, H. & SOLLI, H. 1986. A combined sedimentological and organic geochemical study of the Jurassic/Cretaceous Janusfjellet Formation (Svalbard), Norway. In: JULICH,F. R. G. (ed.). Advances in Organic Geochemistry 1985. Part I Petroleum Geochemistry. Organic Geochemistry, 10, 101-112. HYDROGRAPHICDEPARTMENT, G. B. 1949. Arctic Pilot, 2, Hydrographic Department, HMSO, London. - - 1 9 6 1 . Arctic Pilot, 2, Hydrographic Department, Admiralty, London (Supplement No. 3, 1966). HYV)~RINEN, H. 1969. Trullvatnet: A Flandrian stratigraphical site near Murchisonfjorden, Nordaustlandet, Spitsbergen. Geographiske Annaler, Stockholm, 51, 42-45. IGNATENKO,E. A. 1995. Structural~ectonic zonation and evolution history of the West Arctic metaplatform, Russian Barents Sea. In: HANSLIEN, S. (ed.) Petroluem Exploration and Exploitation in Norway. NPF Special Publication, 4. Elsevier, 305-320. IGO, H. & OKIMURA, Y. 1992. Carboniferous-Permian foraminifers of west Spitsbergen. In: NAKAMURA, K (ed.) Investigations on the Upper CarboniferousUpper Permian succession of West Spitsbergen 1989 1991. Hokkaido University Sapporo, 97-118. I K U 1986. Deep Seismic Profiles of the Barents Sea. Lines 85-D, 85-D1, 85-E, 85-E1, 85-E2, 85-F1, 85-F2, 85-F3, 85-F, 85-H, 85-H1, 85-H2, 85-H3, 85-H5, 85-H4, 85-G (37 sheets). IKU, Stavanger. - - 1 9 8 8 . Barents Sea Mapping Program 1984-1988. IKU, Trondheim. ILYES, R. R. 1995. Acanthodian scales and worm tubes from the Kapp Kjeldsen Division of the Lower Devonian Wood Bay Formation, Spitsbergen. Polar Research, 14, 89-92. - - , OHTA, Y. & GUDDINNGSMO,J. 1995. The Downtonian and Devonian vertebrates of Spitsbergen XV. New Heterostracans from the Lower Devonian Red Bay Group, northern Spitsbergen. Polar Research, 14, 33-42. IMLAY, R. W. 1976. Middle Jurassic (Bajocian and Bathonian) ammonites from Northern Alaska. Professional Paper of the United States Geological Survey, 854. INGOLFSSON,0., ROGNVALDSSON,F., BERGSTEN,H., HEDEN.~S, L., LEMDAHL,G., LIR10, J. M. & SEJRUP, H. P. 1995. Late Quaternary glacial and environmental history of Kongsoya, Svalbard. Polar Research, 14, 123 139. INGRI, J. & PONTER, C. 1987. Rare earth abundance patterns in ferromanganese concretions from the Gulf of Bothnia and the Barents Sea. Geochimica et Cosmochimica Acta, 51, 155-161. ISACHSEN, G. & HOEL, A. 1912-1914. Exploration du Nord-Ouest du Spitzberg enterprise sous les auspices de S.A.S. le Prince Albert 1 de Monaco par la Mission Isachsen. R6sultats des Campagnes Scientifiques. Fasc. 40 (Monaco 1912), 41 (1913), 42 (1914), 43 (1912), 44 (1913). ISAKSEN, G. H. 1996. Organic geochemistry and geohistory of the Triassic succession of Bjornoya, Barents Sea. Organic Geochemistry, 24, 339-349. ISHmASHI, T. & NAg.AZAWA, K. 1989. Triassic ammonites from West Spitsbergen. Memoirs of the Faculty of Science, Kyushu University, Series D Geology, 26, 215-241. IVANOV, I. M. 1934. [Spitsbergen], OGIZ, Sevkraygiz, Arkhargel'sk. IVANOV, S. S., KARASIK,A. M. & SOKOLOV,V. N. 1968. [On the connection between the structure of Spitsbergen and mid-oceanic rift genesis]. Uchenyye Zapiski NIIGA: Regional'naya Geologiya, 12, 224-228. IVERSEN, T. 1926. Hopen (Hope Island), Svalbard. Results of a reconnaissance in the summer 1924. Skrifter om Svalbard og Ishavet, 10, 44. JACKSON, H. R. & GtrNNARSSON, K. 1990. Reconstructions of the Arctic: Mesozoic to Present. Tectonophysics, 172, 303-322. , JOHNSON, G. L., SUNDVOR,E. & MYHRE, A. M. 1984. The Yermak Plateau: hot spot adjacent to a continental margin. Journal of Geophysical Research, 89, 3223 3232. -

-

494

REFERENCES

JAHN, A. 1961. Quantitative analysis of some periglacial processes in Spitsbergen. In: JAHN, A. (ed.) Geophysics, Geography & Geology III. Universytet Wroctawski in Bolestawa Bieruta, Zeszyty Naukowe, Nauki Przyrodnicze, Series B, 5, 3-34. - - 1 9 6 8 . Raised shore lines and terraces at Hornsund, and postglacial vertical movements on Spitsbergen. In: BIRKENMAJER, K. (ed.) Polish Spitsbergen Expedition 1957-1960. Polish Academy of Sciences. JAVA, J. 1988. [Dynamic glacial processes in Southern Spitsbergen]. Katowice University Press. JANtA, J., MOCHNACra, D. & GADEK, B. 1996. The thermal structure of Hansbreen, a tidewater glacier in south Spitsbergen, Svalbard. Polar Research, 15, 53-68. JANSEN, E. & SJOHOLM,J. 1991. Reconstruction of glaciation over the past 6 Myr from ice-born deposits in the Norwegian Sea. Nature, 349, 600-603. - - , BELIE, U. & ERICHSEN,J. A. 1990. Neogene and Pleistocene glaciations in the northern hemisphere and Late Miocene-Pliocene global ice volume fluctuations: evidence from the Norwegian Sea. In: BLEIL, U. & THIEDE, J. (eds) Geological History of the Polar Oceans: Arctic versus Antarctic. Kluwer Academic, Dordrecht, 677-705. JANVIER, P. 1971. La position et la forme du sac nasal chez des Osteostraci. Comptes Rendus de l'Academie des Sciences, Paris, Series D, 272, 2434-2436. - - 1 9 7 7 . Contribution d la connaissanee de la systdmatique et de l'anatomie du genre Boreaspis Stensio (Agnatha, Cephalaspid Osteostraci) du D~vonien inf~rieur du Spitsberg. Annales de Palrontologie, Vertebrrs, 63, 1-32. - - 1 9 8 1 . Norselaspis glacialis n.g., n.sp., et les relations phylogrnrtiques entre les Kiaeraspidiens (Osteostraci) du Drvonien infrrieur du Spitsberg. Palaeovertebrata, 11, 19-131. - - 1 9 8 5 . Les Cgphalaspides du Spitsberg: anatomic, phylogknie et systdmatique des ,

Ostdostracds siluro-d~voniens; rOvision des Ostdostracds de la Formation de Wood Bay (Dgvonien infdrieur du Spitsberg). Cahles Palrontologiqu, Edition du CNRS, Paris. JECZMYK, M. & CIESLINSKI,S. 1986. Heavy mineral spectra from alluvia and ablation cones of the Hornsund area, south Spitsbergen. In: BIRKENMAJER, K. (ed.) Geological Results of the Polish Spitsbergen Expeditions, Part XIV. Studia Geologica Polonica, 89, 45-50. JELENSKA, M. 1985. Paleomagnetism of Permo-Carboniferous sediments of Spitsbergen, Svalbard Archipelago. Acta Geophysiea Poloniea, 33, 279-297. - - 1 9 8 7 . Aspects of pre-Tertiary palaeomagnetism of Spitsbergen and the tectonic implications. Tectonophysics, 139, 99-106. 1988 1989. Paleomagnetic study of Carboniferous sediments and PermoDevonian segment of APWP for Spitsbergen: tectonic implications. Aeta Geophysiea Poloniea, 36, 217-232. & LEWANDOWSKI,M. 1986. Paleomagnetic study of Devonian sandstone from Central Spitsbergen. Geophysical Journal of the Royal Astronomical Society, 87, 617-632. & VINCENZ, S. A. 1987. Origin of the magnetization of Permo-Carboniferous sediments of Spitsbergen, Svalbard Archipelago. Earth and Planetary Science Letters, 85, 173-182. , KADZIALKO, M., KRUCZYK, J. & VINCENZ, A. S. 1978b. Thermomagnetic properties of some Late Mesozoic diabase dikes of south Spitsbergen. Pure and Applied Geophysics, 177, 784-794. , KADZIALKO-HOFMOKL,M. & KRUCZYK, J. 1978a. Palaeomagnetic studies of sedimentary rocks from the Hornsund region, Spitsbergen. Acta Geophysica Polonica, 26, 151-158. - - , KRUCZYK, J. & VINCENZ, S. A. 1978c. Palaeomagnetic reconnaissance of some Palaeozoic sediments of South Spitsbergen, Svalbard Archipelago. LOS (Transactions of the American Geophysical Union), 59, 265. JEPSEN, H. F. & KALSBEEK, F. 1985. Evidence for non-existence of a Carolinidian fold belt in eastern North Greenland. In: GEE, D. G. & STURT, B. A. (eds) The Caledonide Orogen: Scandinavia and related areas. Wiley, London, 1071-1076. JOHANNESSEN, E. P. & EMBRY, A. F. 1989. Sequence correlation. Upper Triassic to Lower Jurassic succession, Canadian and Norwegian Arctic. In: COLLINSON,J. O. (ed.) Correlation in Hydrocarbon Exploration. Graham & Trotman, London, 155-170. & STEEL, R. J. 1992. Mid-Carboniferous extension and rift-infill sequences in the Billefjorden Trough, Svalbard. In: DALLMANN,W. K., ANDRESEN,A. & KRILL, A. (eds). Post-Caledonian Tectonic Evolution of Svalbard. Norsk Geologisk Tidsskrift, 72, 35-48. JOHANNESSON, Z., RAYMOND, C. F. & WADDINGTON, E. 1989. Time-scale for adjustment of glaciers to changes in mass balance. Journal of Glaciology, 35, 355-369. JOHANSEN, S. E., OSTISTY, B. K., BIRKELAND,O., FEDEROVSKY,Y. F., MARTIROSJAN, V. N., BRUUN CHRISTENSEN, O., CHEREDEEV, V. I., IGNATENKO, E. A. & MARGULIS, L. S. 1992. Hydrocarbon potential of the Barents Sea region: play distribution and potential. In: VORREN, T. O. (ed.) Arctic Geology and Petroleum Potential. Norwegian Petroleum Society Special Publications, 2, 273-320. , KIBSGAARD,S., ANDRESEN, A., HENNINGSEN,T. & GRANLI, J. R. 1994. Seismic modelling of a strongly emergent thrust front, West Spitsbergen Fold Belt, Svalbard. American Association of Petroleum Geologists Bulletin, 78, 1018-1027. JOHANSSON,A. 1994. Age determinations of Precambrian granitoids from Ny Friesland and Nordaustlandet, Svalbard Caledonides. Nordiska Geologiska Vintermrtet, 10-13 Jan. 1994 Lulea, 94. , GEE, D. G. & LARIONOV, A. 1994. Precambrian basement within the eastern terrane of the Svalbard Caledonides. Terra abstracts, Abstract supplement No. 1 to Terrra Nova, 7, 109. --, BJORKLUND, L. & WITT-NIESSON, P. 1995. Isotope studies of granitoids from the Bangenhuk Formation, Ny Friesland Caledonides, Svalbard. Geological Magazine, 132, 303-320. -

-

-

-

,

-

-

,

JOHNSEN, S. J., DANSGAARD,W., CLAUSEN, H. B. & LANGWAY, C. C. 1970. Climatic oscillations 1200-2000AD. Nature, 227, 482-483. JOHNSON, H. D., LEVELL, B. K. • SIEDLECKI,S. 1978. Late Precambrian sedimentary rocks in East Finnmark, North Norway and their relationship to the TrollfjordKomagelv fault. Journal of the Geological Society, London, 135, 517-534. JOHNSON, L. C. & ECKHOFF, D. B. 1966. Bathymetry of North Greenland Sea. Deep Sea Research, 13, 1161-1174. JOLv, F. 1959. Carte gdomorphologique de reconnaissance de la presqu'ile de Brogger (Spitsbergen). Spitsberg, Mission Fran~aise 1966. CNRS. JONES, T. R. 1883. Notes on the Palaeozoic bivalved Entomostraca. No. 16: 2. Some Palaeozoic bivalved Entomostraca from Spitzbergen. Annals and Magazine of Natural History, Series 5, 12, 247-249. JONSSON, S. 1982. On the present glaciation of Stor6ya, Svalbard. Geografiska Annaler, 131A, 53-79. --1983. On the geomorphology and past glaciation of Storoya, Svalbard. Geografiske Annaler, 65A, 1-17. KAISER, H. 1970. Die Oberdevon-Flora der B~ireninsei. 3. Mikroflora des H6heren Oberdevons und des Unterkarbons. Palaeontographica, 129, 71-124. 1971. Die Oberdevon-Flora der B/ireninsel 4. Mikroflora der Misery-serie und der F16zleeren Sandstein-serie. Palaeontographica, 135, 127-164. - - 1 9 7 4 . Die mikrofloren und makrofloren des Oberdevon und Untercarbon der B/ireninsel (Ursasandsteinformation). In: Proceedings of the Third International Palynological Conference, Novosibirsk. Nauka, Moscow, 96-97 KALSBEEK, F. 1981. The northward extent of the Archean basement of Greenland a review of R b - S r whole-rock ages. Precambrian Research, 14, 203-219. & TAYLOR,P. N. 1989. Programme of geochronology and isotope geochemistry in the Ammassalik region, South-East Greenland: outline and preliminary results. Rapport, Gronlands Geologiske Undersogelse, 146, 13-16. , NUTMAN, A. P. & TAYLOR, P. N. 1993. Paleoproterozoic basement province in the Caledonian fold belt of North-East Greenland. Precambrian Research, 63, 163-178. KAMB, B. 1987. Glacier surge mechanism based on linked cavity configuration of the basal water conduit system. Journal of Geophysical Research, 92, 9083-9100. KANAT, J. 1984. Jadeite from southern Oscar II Land, Svalbard. Mineralogical Magazine, 48, 301-303. KANAT, L. & MORRIS, A. 1988. A working stratigraphy for central western Oscar II Land, Spitsbergen. Norsk Polarinstitutt Skrifter, 190, 1-25. KANO, A. 1992. Paleoecology of the palaeoaplysinid bioherms of the Lower Permian in Central Spitsbergen. In: NAKAMURA, K. (ed.) Investigations on the upper Carboniferous-upper Permian succession of West Spitsbergen 1989-1991. Hokkaido University, Sapporo, 98-118 KARATAYUTE-TALIMAA,V. N. 1978. [Thelodonts of the Silurian and Devonian of the USSR and Spitsbergen]. Mokslas, Vil'nyus. KARCZEWSKI, L. 1982. Some gastropods and bivalves from the Treskelodden and Kapp Starostin Formations, Hornsund region, Spitsbergen. In: BmRNAT, G. & SZYMANSg.A, W. (eds) Palaeontological Spitsbergen Studies. Palaeontologica Polonica, 43, 97-105. - - 1 9 9 0 . Petuniabukta, Billefjorden, Spitsbergen," Geomorphology map. Scale 1:40 000. A. Mickiewicz University, Poznan. KARLQVIST,A. & CARLSSON,M. L. (eds) 1994. Swedish Research in Svalbard - A Cruise Report. Swedish Polar Secretariat, Stockholm. KAVEMAN, A. J. & KNOLL, A. H. 1995. Neoproterozoic variations in the C-isotope composition of seawater: stratigraphic and biogeochemical implications. Precambrian Research, 73, 27-49. KAYSER, E. 1882. Pal~iozoische Versteinerungen yon Spitzbergen. Zeitschrift der Deutschen Geologischen Gesellschaft, 34, 818. - - 1 9 0 1 . lJber eine Mollusken fauna yon Greyhook auf Spitzbergen. Kungliga Svenska Vetenskapsakademiens Handlingar, 27, 1-24. KAZAKOV, I. N. 1974. [Regional Geology of the World, No. 2. Caledonides of Scandinavia and Spitsbergen]. VINITI, Leningrad. KHLEN, H. B. 1992. Lower Permian sedimentary sequences in Central Spitsbergen, Svalbard. In: NAKAMURA, K. (ed.) Investigations on the Upper CarboniferousUpper Permian succession of West Spitsbergen 1989-1991. Hokkaido University, Sapporo, 127-134. KEILHAU, B. M. 1831. [A journey in East- and West-Finmarken, and also to Bear Island and Spitsbergen in the years 1827 and 1828. Petermanns Mitteilungen Erganzung, 16, 43-67, [German translation of original]. KELLER, B. M. & KRASNOBAEV,A. A. 1983. Late Precambrian geochronology of the European USSR. Geological Magazine, 120, 381-389. KELLOGG,H. E. 1975. Tertiary stratigraphy and tectonism in Svalbard and continental drift. American Association of Petroleum Geologists Bulletin, 59, 465-485. KELLY, P. M., JONES, P. D., SEAR, C. B., CHERRY, B. S. G. & TAVAKOL, R. K. 1982. Variations in surface air temperatures: Part 2 Arctic regions 1881-1980. Monthly Weather Reviews, 110, 71-83. KELLY, S. R. A. 1988. Jurassic through Cretaceous Stratigraphy of the Barents Shelf. In: HARLAND, W. B. & DOWDESWELL E. K. (eds) Geological Evolution of the Barents Shelf Region. Graham & Trotman, London, 109-130. - - 1 9 9 0 . [Biostratigraphy of the Upper Jurassic and Lower Cretaceous of Europe by buchias]. In: MENNER, V. V. (ed.) Trudy Instituta Geologii i Geofiziki, Sibirskoye Otdeleniye. Nauka, Moscow, 129-151. [In Russian with English abstract; in Cyrillic author reads Kelli, S. R.]. KHAIN, V. Y. 1990. The tectonics and magmatism of Europe. International Geology Review, 32, 215-227. KHRAMOV, A. N. & USTRITSKIY,V. I. 1990. Paleopositions of some northern Eurasian tectonic blocks: paleomagnetic and paleobiologic constraints. In: VAN DER VOO, R. t~ SCHMIDT,P. W. (eds). Reliability of Paleomagnetic Data Tectonophysics, 184, 101-109. -

-

REFERENCES KIAER, J. 1916. [Spitsbergen Devonian faunas]. Forhandlinger ved de Skandinaviske Naturforskeres Mote, 16, 490-498. - - 1 9 2 8 . The structure of the mouth of the oldest known vertebrates, Pteraspids and Cephalaspids. Palaeobiologica, 1, 117-134. - - 1 9 3 0 . Ctenaspis, a new genus of Cyathaspidian fishes- a preliminary report. Skrifter om Svalbard og Ishavet, 33, 1-7. - - 1 9 3 2 . The Downtonian and Devonian vertebrates of Spitsbergen. IV. Sub-order Cyathaspida. A preliminary report edited by A. Heintz. Skrifter om Svalbard og Ishavet, 52, 1-138. & HEINTZ, A. 1935. The Downtonian and Devonian vertebrates of Spitsbergen. V. Cyathaspida Pt. 1 Tribe Poraspidei, family Porasidae Kiaer. Skrifter om Svalbard og Ishavet, 40, 1-138. KIDDER, D. L. & SWETT, K. 1989. Basal Cambrian reworked phosphates from Spitsbergen (Norway) and their implications. Geological Magazine, 126, 79-88. KIELAN, Z. 1960. On two olenellid trilobites from Hornsund Vestspitsbergen. In: BIRKENMAJER, K. (ed.). Geological Results of the Polish 1957-1958 Spitsbergen Expedition, Part I. Studia Geologica Polonica, 4, 83-92. KIERES, A. ~; PIESTRZYNSKI,A. 1992. Ore-mineralization of the Hecla Hock succession (Precambrian) around Werenskioldbreen, South Spitsbergen. Studia Geologica Polonica, 98, 115-151. KIMURA, G., OHTA, Y. & NAKAMURA, K. 1990. Minor structures and estimation of tectonic stress during the 'West Spitsbergen Orogeny' in the Festningen region, Spitsbergen. In: TATSUMI,T. (ed.) The Japanese Scientific Expeditions to Svalbard 1983-1988. Kyoikusha, Tokyo, 155-172. KING, L. & VOLK, M. 1994. Glaziologie und Glazialmorphologie des Liefdeund Bockfjordgebietes, NW-Spitzbergen. Zeitschrift ffir Geomorphologie, 145-160. KING, R. E. 1964. Petroleum Exploration and Production in Europe in 1963. American Association of Petroleum Geologists, Bulletin, 48, 1299-1344. KIRKEMO, K. & MC~RK,A. 1987. Kapp K~tre Formation. In: Morur A. (ed.) Geological Excursion Guide to Bjornoya. IKU, Trondheim. KIRSCHWNK,J. L. 1992. A Snowball Earth. In: SCHOPV,J. W. & KLEIN, C. (eds) The Proterozoic Biosphere: A multidisciplinary study. Cambridge University Press, 51-52. KJEMPERUD, A. & FJELDSKAAR,W. 1992. Pleistocene glacial isostasy - implications for petroleum geology. In: LARSEN, R. M., BREKKE, H., LARSEN, B. T. & TALLERAAS, E. (eds) Structural and Tectonic Modelling and its Application to Petroleum Geology. Norwegian Petroleum Society (NPF), Special Publications, 1. Elsevier, Amsterdam, 187-195. KJODE, J., STORETVEDT,K. M., ROBERTS,D. & GIDSKEHAUG,A. 1978. Palaeomagnetic evidence for large scale dextral movement along the Trollfjord-Komagelv Fault, Finnmark, north Norway. Physics of the Earth and Planetary Interiors, 16, 132-144. KLEINSPEHN, K. L. & TEYSSIER, C. 1992. Tectonics of the Paleogene Forlandsundet Basin, Spitsbergen: a preliminary report. In: DALLMANN,W. K., ANDRESEN,A. & KRILL, A. (eds) Post-Caledonian Tectonic Evolution ofSvalbard. Norsk Geologisk Tidsskrift, 72, 93-104. & 1993. Paleostress stratigraphy of the Paleogene Central Basin, Spitsbergen: implications for deformation partitioning along a transform margin. Abstract supplement No. 2. Terra Abstracts, 5, 17. , PERSHING, J. & TEYSSIER, C. 1989. Paleostress stratigraphy: a new technique for analyzing tectonic control ON sedimentary-basin subsidence. Geology, 17, 253-256. , STEEL, R. J., JOHANNESSEN, E. & NETLAND, A. 1984. Conglomeratic fan-delta sequences, Late Carboniferous - Early Permian, Western Spitsbergen. In: KOSTER, E. H. & STEEL, R. J. (eds). Sedimentology of Gravels and Conglomerates. Memoirs of the Canadian Society of Petroleum Geologists, 10, 279-294. KLIMACZEWSKI,M. 1960. Geomorphological studies of the western part of Spitsbergen between Kongsfjorden and Eidembukta. Zesz Nan Unuv Jagiellonskiego, 23. KLITGORD,K. D. & SCHOUTEN,H. 1986. Plate Kinematics and the Central Atlantic. In: VOGT, P. R. & TUCHOLKE, B. E. (eds) The Western North Atlantic Region. The Geological Society of America. The Geology of North America, M, 351-378. KLITIN, K. A. 1960. [On the tectonics of Spitsbergen]. Izvestiya Akademii Nauk SSSR. Seriya geologicheskaya, 10, 62-69. - - 1 9 6 4 . The Caledonides of Spitsbergen. In: BOGDANOV,A. A,, MOURATOV,N. S. & SHATSKY, N. S. (eds) Tectonics of Europe. Explanatory note to International Tectonic Map of Europe, Scale 1 : 2 500 000. Moscow. 1965. [Baykalian folding and tillite-like conglomerates in the Caledonian sections of Europe and Greenland]. Doklady Akademii Nauk SSSR, 163, 702-705. - - - 1 9 8 1 . [The paleoclimate of Spitsbergen and problems of Arctic tectonics]. Priroda, 113-114. - - 1 9 8 1 . [The problem of the structural links between Spitsbergen and Scandinavia and their mutual relationship to the Atlantic Ocean]. In: Problemy tektoniki zemnoy kory [Problems of the Tectonics of the Earth's Crust], Moscow, 226-236. - - 1 9 8 3 . [The structure of the sedimentary cover in the sea around Spitsbergen in the North Atlantic]. Byulleten' Moskovskogo Obshchestva Ispytateley Prirody, Otdel Geologicheskiy, 58, 16-23. - - 1 9 8 6 . [Tectonics of the sedimentary cover of the western part of the Barents Sea]. -

-

9 7 ,

-

-

1 9 8 1 ,

Byulleten' Moskovskogo Obshchestva Ispytateley Prirody, Otdel Geologicheskiy, 61, 13-24. 1988. [Relationship of the Nordkapp platform and the west Barents perioceanic downwarps]. Izvestiya AN SSSR, Seriya Geologicheskaya, 108-114. KLUBOV, B. A. 1964. [Triassic rocks and oil prospects of Edgeoya (Spitsbergen Archipelago)]. In: SOKOLOV,V. N. (ed.) Conference on the Geology of Spitsbergen, Leningrad 1964: Summary of Contributions. NIIGA, Leningrad, 10-11. 1965a. [Triassic and Jurassic deposits of Wilhelmoya]. In: SOKOLOV,V. N. (ed.) Materialy po geologii Shpitsbergena [Materials on the Geology of Spitsbergen]. NIIGA, Leningrad, 174-184.

495

[A geological sketch of Edgeoya]. In: SOKOLOV,W. N. (ed.) Materialy po Geologii Shpitsbergena. NIIGA, Leningrad, 71-82. - - 1 9 6 5 c . [The main features of the geological structure of Barentsoya]. In: SOKOLOV, V. N. (ed.) Materialy po Geologii Shpitsbergena. NIIGA, Leningrad, 83-92. - - 1 9 6 5 d . [Concerning the occurrence of Permian rocks on Barentsoya]. Doklady Akademii Nauk SSSR, 162, 629-631. - - 1 9 6 5 e . [Basic features of the Geological structure of Bear Island. Materials on the Geology of Spitsbergen]. N I I G A Leningrad, [Scholarly Papers on Regional Geology]. - - 1 9 7 0 . Triassic and Jurassic deposits of Wilhelmoya. National Lending Library for Science and Technology, Boston spa, Yorkshire, 2, 182-192. - - , ALEKSEYEVA,A. B. & DROZDOVA, I. N. 1967. [On Triassic coal of Spitsbergen]. In: SOKOLOV, V. N. (ed.) Materialy po stratigrafii Shpitsbergena. NIIGA, Leningrad, 170-177. KNARUD, R. 1984. Depositional Environment and Paleogeographical Reconstructions of the Upper Triassic Succession on Svalbard. Report 046341.00/02/84. IKU, Trondheim. KNIPOWITSCH, N. 1900. (Jber die postpliocenen Mullusken und Brachiopoden yon Spitzbergen ( Zoologiscke Ergebnisse du russischen Expedition tach Spitsbergen in Jalue 1899). Bulletin de l'Acadrmie Imperiale de Sciences de St. Petersbourg 12. KNOLL, A. H. 1981. Chronostratigraphic age of Late Precambrian tillites in Svalbard. Appendix to Hambrey et al. "Late Precambrian tillites of Svalbard". In: HAMBREY, M. J. & HARLAND W. B. (eds) Earth's Pre-Pleistocene Glacial Record. Cambridge University Press. --1982. Micro-fossil based biostratigraphy of the Precambrian Hecla-Hoek sequence, Nordaustlandet, Svalbard. Geological Magazine, 119, 269-279. - - 1 9 8 2 . Microfossils from the Late Precambrian Draken Conglomerate, Ny Friesland, Svalbard. Journal of Paleontology, 56, 755-790. - - 1 9 8 2 . Paleoecology of Late Precambrian microbial assemblages. In: NIKLAS, K. J. (ed.) Paleobotany, Paleoecology, and Evolution, 1. Praeger, New York, 17-54. - - 1 9 8 4 . Microbiotas of the Late Precambrian Hunnberg Formation Nordaustlandet, Svalbard. Journal of Paleontology, 58, 131-162. - - 1 9 8 5 . A paleobiological perspective on sabkhas. In: FRIEDMAN, G. M. KRUMBEIN, W. E. (eds) Hypersaline Ecosystems. Ecological Studies, 53, 407-425. - - 1 9 8 5 . Exceptional preservation of photosynthetic organisms in silicified carbonates and silicified peats. Philosophical Transactions of the Royal Society of London, B311, 111-122. - - 1 9 8 5 . Patterns of evolution in the Archean and Proterozoic cons. Paleobiology, 11, 53 -64. - - 1 9 8 9 . The microbiological information in Proterozoic rocks. In: COHEN, Y & ROSENBERG, E. (eds) Microbiai Mats - Physiological Ecology of Benthic Microbial Communities. American Society for Microbiology, Washington, DC, 469-484. - - 1 9 9 1 . End of the Proterozoic Eon. Scientific American, 265, 64-73. - - 1 9 9 2 . Vendian microfossils in metasedimentary cherts of the Scotia Group, Prins Kads Forland, Svalbard. Palaeontology, 35, 751-774. - - 1 9 9 2 . The early evolution of eukaryotes: a geological perspective. Science, 256, 622-627. - - 1 9 9 2 . Biological and biogeochemical preludes to the Ediacaran radiation. In: LIPPS, J. H. ~:; SIGNOR, P. W. (eds) Origin and Early Evolution of the Metazoa. Plenum, New York, pp. 53-84. t~ BUTTERFIELD, N. J. 1989. New window on Proterozoic life. Nature, 337, 602-603. & CALDER, S. 1983. Microbiotas of the Late Precambrian Ryss6 Formation, Nordaustlandet, Svalbard. Palaeontology, 26, 467-496. & GOLUBIC, S. 1979. Anatomy and taphonomy of a Precambrian algal stromatolite. Precambrian Research, 10, 115-151. -& OWrA, Y. 1988. Microfossils in metasediments from Prins Karls Forland, western Svalbard. Polar Research, 6, 59-67. & SWETT,K. 1985. Micropaleontology of the Late Proterozoic Veteranen Group, Spitsbergen. Palaeontology, 28, 451-473 + plates. & 1987. Micropaleontology across the Precambrian-Cambrian boundary in Spitsbergen. Journal of Paleontology, 61, 898-926. & 1990. Carbonate deposition during the Late Proterozoic era: an example from Spitsbergen. In: KNOLL, A. H. & OSTROM,J. H. (eds) Proterozoie Evolution and Environments. American Journal of Science, 290-A, 104-132. --& WALTER, M. R. 1992. Latest Proterozoic stratigraphy and Earth history. Nature, 356, 673-678. - - , HAYES, J. M., KAUFMAN,J., SwEar, K. & LAMBERT,I. 1986. Secular variation in carbon isotope ratios from Upper Proterozoic successions of Svalbard and East Greenland. Nature, 321, 832-838. , KAVFMAN, A. J., SEMIKHATOV,M. A. & GROTZINGER,J. P. 1995. Sizing up the sub-Tommotian unconformity in Siberia. Geology, 23, 1139-1143. , SWEar, K. & BURKrtARDT, E. 1989. Paleoenvironmental distribution of microfossils and stromatolites in the Upper Proterozoic Backlundtoppen Formation, Spitsbergen. Journal of Paleontology, 63, 129-145. --, -& MARK, J. 1991. Paleobiology of a Neoproterozoic tidal flat/lagoonal complex: the Draken Conglomerate Formation, Spitsbergen. Journal of Paleontology, 65, 531-569. KNOTHE, H. 1931. Spitzbergen, eine landeskundliehe Studie. Petermanns Mitteilungen Erganzung, 211. KNUTSEN, S. M. & LARSEN, K. I. 1997. The late Mesozoic and Cenozoic evolution of the Sorrestsnaget Basin: A tectonostratigraphic mirror for regional events along the southwestern Barents Sea Margin? Marine and Petroleum Geology, 14, 27-54. , RICHARDSEN,G., VORREN, T. O. et al. 1993. Late Miocene-Pleistocene sequence stratigraphy and mass movement on the western Barents Sea margin. In: VORRENT, T. O. et al. (eds) Arctic Geology and Petroleum Potential. NPF Special Publication, 2. Elsevier, 573-606. --1965b.

-

-

-

-

-

-

-

-

-

-

496

REFERENCES

KOBAYASHI,T. 1987. A Permian trilobite from Spitsbergen, Norway, with a note on biogeographic bearing of the genus Neoproetus. Proceedings of the Japan Academy, 63B, 139-142. KOERN~R, R. M. 1977. Devon Island Ice Cap: core stratigraphy and paleoclimate. Science, 196, 15-18. KOETTLTTZ,R. 1898. Observations on the Geology of Franz Josef Land. Quarterly Journal of the Geological Society of London, 54, 620-645. KON1NCK, L. de 1846. Notice sur quelquesfossiles du Spitzberg. Bulletin de l'Academie royale de belgique 16. - - 1 8 4 9 . Nouvelle notice sur les fossiles du Spitzberg. Bulletin de l'Academie royale de belgique 16 (Bruxelles). KOHLER-LoPEZ, M. & LEHMANN, U. 1984. The Triassic ammonite Aristoptychites kolymensis (Kiparisova) from Botneheia, Spitsbergen. Polar Research, 2, 61-75. KOPIK, J. 1968. Remarks on some Toarcian ammonites from the Hornsund area, Vestspitzbergen. Studia Geologica Polonica, 21, 33-52. -& WtERZBOWSK~,A. 1988. Ammonites and stratigraphy of the Bathonian and Callovian at Janusfjellet and Wimanfjellet, Sassenfjorden, Spitsbergen. Acta Palaeontologica Polonica, 33, 145-168. KORCHINSKAYA,M. V. 1969. [Olenekian ammonites of Spitsbergen]. In: GERKE, A. A. (ed.) Uchenyye Zapiski NIIGA. Paleontologiya i biogstratigrafiya, 27, NIIGA, Leningrad, 80-90. - - 1 9 7 0 . [Biostratigraphy of the deposits of the Olenekian stage of Spitsbergen]. Doklady Akademii Nauk SSSR, 193, l 130-1133. - - 1 9 7 1 . The biostratigraphy of the Triassic of Spitsbergen. Bulletin of Canadian Petroleum Geology, 19, 334-335. - - 1 9 7 2 a . Biostratigraphy of Triassic deposits of Svalbard. Bulletin of Canadian Petroleum Geology, 20, 742-749. - - 1 9 7 2 b . The distribution of Nathorstites in the Triassic deposits of Svalbard. In: SOKOLOV, V. N. & VASILEVSKAYA, N. D. (eds) Mezozoyskiye otlozheniya Sval'barda [Mesozoic Deposits of Svalbard], NIIGA, Leningrad, 64-72. - - 1 9 7 3 . Biostratigraphy of Triassic deposits of Svalbard. In: The Permian and Triassic systems and their mutual boundary. Memoirs of the Canadian Society of Petroleum Geologists, 2, 261-268. - - 1 9 8 0 . [Early Norian fauna of the Svalbard Archipelago]. In: SEMEVSKlV,D. V. (ed.) [Geology of the Sedimentary Mantle of the Svalbard Archipelago. A Collection of Scientific Papers]. NIIGA, Leningrad, 30-43. - - 1 9 8 2 . [An Explanatory Note to the Stratigraphic Scheme of the Mesozoic (Trias) of Svalbard], "Sevmorgeo", Leningrad. - - d 9 8 3 . [New Ceratids from Upper Olenekian deposits of Spitsbergen]. Paleontologicheskiy Zhurnal, 3, 109-112. - - 1 9 8 6 . [Biostratigraphy of the Induan Stage of Svalbard]. In: KRASIL'StiCHIKOV, A . A . & MmZAVEV, M. H. (eds) Geology of the Sedimentary Cover of the Spitsbergen Archipelago. Sevmorgeologiya, Leningrad, 78-89. & VAVlLOV, M. N. 1987. [Early Induan ammonoids of Spitsbergen]. /n: ZAKHAROV, YU. D. & ONOPRIYENKO,YU. I. (eds) Problemy biostratigrafii permi i triasa vostoka SSSR [Problems of the Permian and Triassic Biostratigraphy of the Eastern USSR]. DVNTs, Biological-Pedological Institute, Vladivostok, 64-73. - - - , ARKAD'YEV,V. V. & VAVILOV, M. N. 1989. [Biostratigraphy and correlation of the Ladinian stage of the Middle Trias of the Boreal Province]. Sovetskaya Geologiya, 10, 40-47. , KLUBOV,B. A. & PCHELINA,T. M. 1967. [On the boundary of the Middle and Upper Triassic in Spitsbergen]. In: SOKOLOV,V. N. (ed.) Materiali po stratigraphii Shpitsbergena. NI1GA, Leningrad, 159-169 [in Russian]. KORINEVSKIY, V. G. 1988. A very important episode in the tectonic history of the southern Urals. Geotectonics, 22, 119. KORJArON, V. S. 1975. [Position and morphology of glaciers]. Oledenenie Spitsbergena, NAUKA, 7-39. KORNFELD, J. A. 1965. Amoseas' Spitsbergen test is world's northernmost wild cat. Worm Oil, October, 164-166. KOROTKEVlCH,V. D. 1966. Comparison of Upper Triassic spore and pollen complexes from the Lena-Olenek interfluve and the islands of Vestspitsbergen. Uchenyye Zapiski NI1G. Paleontologiya i Biostratigrafiya, 12, 81-85. - - 1 9 6 9 . Spore-pollen characteristics of Upper Triassic deposits in Vestspitsbergen. In: GERKE, A. A. (ed.) Uchenyye Zapiski NIIGA. Paleontologiya i Biostratigrafiya, 28, NIIGA, Leningrad, 61-66. KORStJN, S. A., POGODINA, I. A., FORMAN, S. L. & LUBINSKI, D. J. 1995. Recent foraminifera in glaciomarine sediments from the arctic fjords of Novaya Zemlya and Svalbard. Polar Research, 14, 15-32. KOSAK, H.-P. 1967. Die Polarforschung, Brannschweig, 472pp. KOTENEV, B. N. & MATISHOV,G. G. 1972. [The sea-floor relief in the region of Vest Spitsbergen]. Voprosy Okeanologii i Kompleksnykh issledokinii shel. Barentserai Belogo Morei, Murmansk [in Russian]. KOTLUKOV,V. A. 1933. [The coal at Ice Fjord]. Gornyy Zhurnal, 9, 53-59. - - 1 9 3 5 . [Coal from some deposits in Spitsbergen]. Khimiya Tverdogo Topliva, 4, 195-201. - - 1 9 3 6 . [The geological structure and coal deposits of Barentsburg and of the Boheman Tundra (Western Spitsbergen)]. Trudy Leningradskogo Geologicheskogo Tresta, 11, 1-40 [with English summary]. KOTLYAKOV,V. M., ZAGORODNOV,V. S. & NIKOLAYEV,V. 1. 1990. Drilling on ice caps in the Soviet Arctic and on Svalbard and prospects of ice core treatment. In: KOTLYAKOV, V. M. & SOKOLOV, V. Y. (eds) Arctic Research: Advances and Prospects, 2, Nauka, Moscow, 5-18. --, KOROTKOV, I. M., NIKOLAYEV, V. I., PETROV, V. N., BARKOV, N. I. & KLEMENT'YEV, O. L. 1989. [Reconstruction of the Holocene climate from the results of ice-core studies on the Vavilov Dome, Severnaya Zemlya]. Materialy Glyatsiologicheskikh lssledovaniy, 67, 103-108. -

-

KOVALEVA, G. A. 1983. [The post-Archean basic-ultrabasic association of the Spitsbergen Archipelago]. In: KRASIL'SHCHI~:OV,A. A. & BASOV, V. S. (eds) Geologiya Shpitsbergena: sbornik nauchnykh trudov [The Geology of Spitsbergen: a Collection of Papers]. "Sevmorgeo", Leningrad, 87-95. - - & BuRov, Y. P. 1976. [Main peculiarities of the Meso-Cenozoic basitic complexes of the Archipelago of Svalbard]. In: SOKOLOV,V. N. (ed.) Geology of Svalbard. A Collection of Articles, NIIGA, Leningrad, 126-138 [in Russian]. --, SHKATOV,YEP. & SEMEVSKIV,D. V. 1983. [The geostrnctural position of the Spitsbergen Archipelago]. In: KRASlL'SnCnIKOV, A. A. & BAsov, V. A. (eds) Geologiya Shpitsbergena: sbornik nauchnykh trudov [The Geology of Spitsbergen: a Collection of Papers]. "Sevmorgeo", Leningrad, 5-17. KOWALLIS, B. J. & CR~,DDOCK, C. 1982. The occurrence of Permian blocks near Calypsobyen, Spitsbergen, and their significance. Polar Research, 2, 105-108. -& - - 1 9 8 4 . Stratigraphy and structure of the Kapp Lyell diamictites (Upper Proterozoic), Spitsbergen. Geological Society of America Bulletin, 95, 1293-1302. KoYL H., TALBOT,C. J. & TORUDBAKKEN,B. O. 1995. Analogue models of salt diapirs and seismic interpretation in the Nordkapp Basin, Norway. Petroleum Geoscience, 1, 185-192. KRAJEWSKI, K. P. 1989. Organic geochemistry of a phosphorite to black shale transgressive succession: Wilhelmoya and Janusfjellet Formations (RhaetianJurassic) in central Spitsbergen, Arctic Ocean. Chemical Geology, 74, 249-263. - - - 1 9 9 0 . Phosphorization in a starved shallow shelf environment: the Brentskardhaugen Bed (Toarcian-Bajocian) in Spitsbergen. Polish Polar Research, 11,331-344. - - 1 9 9 2 a . Phosphorite-bearing sequence of the Wilhelmoya Formation in Van Keulenfjorden, Spitsbergen. Studia Geologica Polonica, 98, 171-199. - - 1 9 9 2 b . Phosphorite-bearing sequence of the Wilhelmoya Formation at Hornsund and along western coast of Sorkapp Land, Spitsbergen. Studia Geologica Polonica, 98, 201-233. KRASIL'St~CmKOV, A. A. 1964. New data on the geology of the northern part of the Spitsbergen archipelago. In: SoKoeov, V. N. (ed.) Conference on the Geology of Spitsbergen, Leningrad 1964: Summary of Contributions. NIIGA, Leningrad, 2355. - - 1 9 6 5 . [Some aspects of the geological history of North Spitsbergen[. In: So•oLov, V. N. (ed.) Materialy po Geologii Shpitsbergena, NIIGA, Leningrad, 29-44. - - 1 9 6 5 . [Stratigraphy of the Upper Proterozoic deposits around Murchisonfjorden, Nordaustlandet I. In: SOKOLOV,V. N. (ed.) Materialy po Geologii Shpitsbergena, NIIGA, Leningrad, 102--111. - - 1 9 6 7 . [Tillite-like rocks of North East Land]. In: SOKOLOV,V. N. (ed.) Materialipo stratigraphii Shpitsbergena, NIIGA, Leningrad, 36-62. - - 1 9 6 9 . [Caledonian intrusions of the Spitsbergen Archipelago]. Uchenyye Zapiski N|IG. Paleontologiya i Biostratigrafiya, 16. - - 1 9 7 0 . [Scheme for the Precambrian and Lower Palaeozoic stratigraphy of the Spitsbergen Archipelago]. Doklady Akademii Nauk SSS R, 194, 1153-1156. - - 1 9 7 3 . [Stratigraphy and paleotectonics of the Precambrian-early Paleozoic of Spitsbergen]. Trudy Arkticheskogo Nauchno-Issledovatel'skogo Instituta, 172, 1-120. - - 1 9 7 9 . Stratigraphy and tectonics of the Precambrian of Svalbard. Norsk Polarinstitutt Skrifter, 167, 73-79. - - 1 9 8 3 . ]Some problems of correlation of Precambrian complexes of the Spitsbergen Archipelago]. In: KRASIL'SHCmKOV, A. A. & BASOV, V. A. (eds) Geologiya Shpitsbergena: sbornik nauchnykh trudov [The Geology of Spitsbergen: a Collection of Papers]. "Sevmorgeo", Leningrad, 18-27. -(ed.) 1996. Soviet Geological Research in Svalbard 1962-1992, extended abstracts of unpublished reports Spitsbergen. Norsk Polarinstitutt Meddelelser, 139. -& BAsov, V. A. (eds) 1983. [The Geology of Spitsbergen." a Collection of Papers], PGO "Sevmorgeo", Leningrad. & KOVALEVA,G. A. 1979. Precambrian rock stratigraphic units of the west coast of Spitsbergen. Norsk Polarinstitutt Skrifter, 167, 81-88. & LlVSHITS,Y. Y. 1974. Tectonics of Bear Island (Bjornoya). Geotectonics, 8, 215-221. & LOPATIN,B. G. 1996. Preliminary results of the study of Caledonian granitoids and Hecla Hock gneisses in northern Svalbard. In: KRASlL'SHCm~COV,A. A. (ed.) Soviet Geological Research in Svalbard 1962-1992, extended abstracts of unpublished reports Spitsbergen. Norsk Polarinstitutt Meddelelser, 139, 16. & MIL'SH'rEIN,V. YE. 1975. [On the age of the "Series of Ancient Dolomites" on Bjornoya (Barents Sea)]. Doklady Akademii Nauk SSSR, 225, 161-163. -& MIP~ZAYEV,M. N. (eds) 1986. [The Geology of the Sedimentary Cover of the Spitsbergen Archipelago. A Collection of Papers], "Sevmorgeo", Leningrad. & ABAKUMOV,S. A. et al. 1996. Main features of the Geology of Svalbard. In: KRASIL'SHCHIKOV,A. A. (ed.) Soviet Geological Research in Svalbard 1962-1992, extended abstracts of unpublished reports Spitsbergen. Norsk Polarinstitutt Meddelelser, 139, 8-16. --, GOLOVANOV,N. P. & MIL'SHTEIN,V. Y. 1965/1970. [Stratigraphy of the Upper Proterozoic deposits around Murchisonfjorden, Nordaustlandet]. In: SOKOLOV,V. N. (ed.) MateriaIy po geologii Shpitsbergena. Inst. for Geol. of Arctic, Leningrad, -

-

-

-

-

-

-

-

-

-

1

--,

0

2

-

1

1

1

.

KUBANESKIY,A. P. & OrtTa, Y. 1995. Surface magnetic anomaly study on the eastern part of the Forlandsundet Graben. Polar Research, 14, 55-68. - - , KRYLOV,A. J. & ALPAPYSHEV,O. A. 1964. [The age of some granitic and gneissic rocks from the northern part of Spitsbergen Archipelago]. Doklady Akademii Nauk SSSR, 159, 796-798. --, KUNO, V. G. & SmsovA, T. E. 1996. The geology of basement of the epiCaledonian platform of Svalbard. In: KRASm'SHCHmOV, A. A. (ed.) Soviet Geological Research in Svalbard 1962-1992, extended abstracts of unpublished reports Spitsbergen. Norsk Polarinstitutt Meddelelser, 139, 20-22. K ~ s o v , D. D. 1978. The Barents Ice Sheet as a relay regulator of glacial-interglacial alternation. Quaternary Research, 9 288-299.

REFERENCES KRAVETS, V. S,, MESEZHNIKOV, M. S. & SLONIMISKIY,G. A. 1976. [Structure of Jurassic-Lower Cretaceous strata in the basin of the Pechora River]. Trudy VNIGRI, 388, 27-41. KREMENETSKAYA, Y. O. 1983. [Deep siting of some seismic boundaries on the Kola Peninsula and Vestspitsbergen]. Geofiz. Issled. na Yevrop. Severe SSSR, 1983, 44-50. KRISTOEFERSON,Y. 1980. A microearthquake survey of the Svalbard region. Final report, Phase I. Norsar Technical Report No. 1/80. NTNF/Norsar, Kjeller. - - 1 9 9 0 . Eurasia Basin. In: GRANTZ, A., JOHNSON, L. & SWEENEY, J. F. (eds) The Arctic Ocean Region. The Geology of North America, Geological Society of America, L, 365-378. -& ELVERHOI,A. 1978. A diapir structure in Bjornoyrenna. Norsk Polarinstitutt Arbok, 1977, 189-198, - - - & TALWANI,M. 1977. Extinct triple junction south of Greenland and the Tertiary motion of Greenland relative to North America. Geological Society of America Bulletin, 88, 1037-1049. --, MILL/MAN, J. D. & ELLIS, J. P. 1984. Unconsolidated sediments and shallow structure of the northern Barents Sea. Norsk Polarinstitutt Skrifter, 180, 25-39. - - , SAND, M., BESKOW,B. & OHTA, Y. 1988. Western Parents Sea, Bathymetry. Scale 1.1.5M. Norsk Polarinstitutt. KROEMER, E. A., MAUSBACHER,J., M13LLER, J. & SCHACHT, R. 1994. First results of structural and sedimentological investigations in the Liefdefjorden and Woodfjorden (northern Spitsbergen). Zeitschriftffir Geomorphologie, 97, 49-64. KRONER, A. 8z COMPSTON, W. 1990. Archaean tonalitic gneiss of Finnish Lapland revisited: zircon ion-microprobe ages. Contributions to Mineralogy and Petrology, 104, 348-352. KRUMSIEK, K., NAGEL, J. & NAIRN, A. E. M. 1968. Record of palaeomagnetic measurements on some igneous rocks from the Isfjorden region, Spitsbergen. Norsk Polarinstitutt Arbok 1966, 76-83. Kuc, M. 1964. [Deglaciation of Treskelen-Treskelodden in Hornsund, Vestspitsbergen, as shown by vegetation]. Studia Geologica Polonica 11. KUKLA, G. J. 1977. Pleistocene land-sea correlations. I. Europe. Earth Science Reviews, 13, 307-374. KULLING, O. 1930. Stratigraphic studies of the geology of Northeast Greenland. Meddelelser om Gronland, 74, 317-346. - - 1 9 3 2 . [Some geological results from the 1931 expedition to Nordaustlandet]. Geologiska Ffreningens Stockholm Frrhandlingar, 54, 138-146. - - 1 9 3 4 . Scientific results of the Swedish-Norwegian Arctic Expedition in the summer of 1931. Part XI. The "Hekla Hock Formation" round Hinlopenstredet. Geografiske Annaler, 16, 161-254. - - 1 9 3 7 . Ueber prfikarbonische Klimazeugnisse aus Svalbard (B/ireninsel, Spitzbergen und umliegenden Inseln). In: International Geological Congress, XVII Session, Abstract Papers, International Geological Congress, Leningrad, 211. 1951. ]Traces of the Varanger Ice age in Norbotten]. Sveriges Geologiska Unders6kning, Series C 503. & AHLMANN, H. W. 1936. Observations on raised beaches and their faunas. Surface makings. Geographiske Annaler, Stockholm, 18, 1-19. KUMMEL, B. 1961. The Spitsbergen Arctoceratids. Bulletin of the Museum of Comparative Zoology, Harvard, 123, 499-532. KUNIN, N. Y., USENKO, S. V., VINOGRADOV,A. V. & KERUSOV, I. N. 1990. Regional seismostratigraphy of the sedimentary section beneath the Barents Shelf. International Geology Review, 32, 34-46. KURININ, R. G. 1965. [Density and magnetic susceptibility of Spitsbergen rocks]. In: SOKOLOV, V. N. (ed.) Materialy po Geologii Shpitsbergena. NIIGA, Leningrad, 284-287 [in Russian]. KURKOV, A. V. & NEIZVESTNOV,Y. V. 1983. [Aquifer complexes of the Spitsbergen Archipelago]. In: NEIZVESTNOV,YA, V. & SEMEVSKIY,D. V. (eds) Gidrogeologiya,

Inzhenernaya Geologiya, Geomorfologiya Arkhipelaga Shpitsbergen [The Hydrogeology, Engineering Geology and Geomorphology of the Spitsbergen Archipelago]. PGO "Sevmorgeo", Leningrad, 41-53. KUZNETSOV, Ju. A. 1964. [Main types of magmatic formations]. Nedra, Moskva. KVACEK, Z. & MANUM, S. B. 1993. Ferns in the Spitsbergen Paleogene. Palaeontographica, B230, 169-181. --, -& BOULTER, M. C. 1994. Angiosperms from the Palaeogene of Spitsbergen, including an unfinished work by A. G. Nathorst. Palaeontographiea, 8, 103-128. KVASOV, D. D. & BLAZHCHEIN,A. I. 1978. The key to the source of the Pliocene and Pleistocene glaciation is at the bottom of the Barents sea. Nature, 273, 138-140. LABERG, J. S. & VORREN, T. O. 1995. Late Weichselian submarine debris flow deposits on the Bear Island Trough Mouth Fan. Marine Geology, 127, 45-72. & - - 1 9 9 5 . High resolution seismic and stratigraphic data from the Bear Island Fan Plate 76. In: Seafloor Atlas of the Northern Norwegian-Greenland Sea. Norsk Polarinstitutt, 165-166. & 1996. The glacier fed fan at the mouth of the Storfjorden trough, western Barents Sea: a comparitive study. Geologische Rundschau, 85, 338-349. LAMAR, D. L. t~; DOUGLASS, D. N. 1995. Geology of an area astride the Billefjorden Fault Zone, northern Dickson Land, Spitsbergen, Svalbard. Norsk Polarinstitutt Skrifter, 197, 1-43 (Oslo). , REED, W. E. & DOUGLASS,D. N. 1986. The Billefjorden fault zone, Spitsbergen: is it part of a major Late Devonian transform? Geological Society of America Bulletin, 97, 1083-1088. LAMBECK, K. 1996. Late Cenozoic evolution of the western Barents Sea-Svalbard continental margin. In: SOLHEIM, A., RHS, F., ELVERI-I~, A., FALEIDE, J. I., JENSEN, L. N. & CLOETINGH,S. (eds) Global and Planetary Change, 12, 53-74. LAMMERS, S., SUESS, E. & HOVLAND, M. 1995. A large methane plume east of Bear Island (Barents Sea): implications for the marine methane cycle. Geologiske Rundschau, 84, 59-66. -

-

-

-

497

LAMONT, J. 1860. Notes about Spitzbergen in 1859. Quarterly Journal of the Geological Society of London, 16, 428-442. LAMPLUGH,G. W. 1910. Stockholm to Spitsbergen: the geologist's pilgrimage. Nature, 85, 152-157. - - 1 9 1 1 . On the shelly moraine of the Sefstr6m Glacier and other Spitsbergen phenomena illustrative of British glacial conditions. Proceedings of the Yorkshire Geological Society, New Series, 17, 1909-1911. LANDVIK,J. Y., HANSEN,A., KELLY, M., SALVIGSEN,O., SLETTERMARK,O. t~ STUBDRUP, O. P. 1992. The last deglaciation and glaciomarine/marine sedimentation on Barentsoya and Edgeoya, eastern Svalbard. LUNDQUA Report, 35, 61-83. --, HJORT, C., MANGERUD, J., MOLLER, P. t~; SALV1GSEN,O. 1995. The Quaternary record of eastern Svalbard - an overview. Polar Research, 14, 95-103. LANKESTER,E. R. 1884. Report on fragments of fossil fishes from the Palaeozoic strata of Spitsbergen. Kungliga Svenska Vetenskapsakademiens Handlingar, 20, 1-7. LAPTAS, A. 1986. Sedimentary evolution of Lower Ordovician carbonate sequence in south Spitsbergen. In: BIRKENMAJER, K. (ed.) Geological Results of the Polish Spitsbergen Expeditions, Part )(IV. Studia Geologica Polonica, 89, 7-27. LARIONOV, A. N., JOHANSSON,/~k., TEBENKOV, A. M. & SIROTKIN,A. N. 1995. U-Pb zircon ages from the Eskolabreen Formation southern Ny Friesland, Svalbard. Norsk Geologisk Tidsskrift, 75, 247-257. LARSEN, B. T. 1988. Tertiary thrust tectonics in the east of Spitsbergen, and implications for the plate-tectonic development of the North-Atlantic. In: DALLMANN, W. K., OHTA, Y. & ANDRESEN, A. (eds) Tertiary Tectonics of Svalbard. Norsk Polarinstitutt, Report Series, 46, 85-88. LARSEN, H. C., SAUNDERS, A. D. & CLIFT, P. 1994. East Greenland Margin. Joides Journal, 20, 22-26. LARSEN, V. B. 1987. A synthesis of tectonically-related stratigraphy in the North Atlantic-Arctic region from Aalenian to Cenomanian time. Norsk Geologisk Tidsskrift, 67, 281 293. LARSON, S. 1957. The suborder Charadrii in Arctic and Boreal areas during the Tertiary and Pleistocene. Acta Vertebratica, 1, 1-24. LAURITZEN, O. 1977. Development patterns of gypsum/anhydrite in Lower Permian sediments of central Spitsbergen - a suggested classification. Norsk Polarinstitutt .4rbok 1976, 5-20. - - 1 9 8 1 . Investigations of Carboniferous and Permian sediments in Svalbard. I: The development of the Gipshuken Formation (Lower Permian) at Trollfuglfjella in Central Spitsbergen, Svalbard. II: The Carboniferous and Permian stratigraphy of the Wahlenbergfjorden area, Nordaustlandet, Svalbard. Norsk Polarinstitutt Skrifter, 176, 1-44. - - 1 9 8 3 . Karstic surface in the Lower Permian sabkha sequence of the Gipshuken Formation, central Spitsbergen, Svalbard. Polar Research, 1, 157-160. & HJELLE, A. 1982. Geological Map of Svalbard 1:500000, Sheet A4G. Nordaustlandet. Norsk Polarinstitutt, Skrifter 154D. -& OItTA, Y. 1984. Geological Map of Svalbard. Sheet 4G, Nordaustlandet. Scale 500 000. Norsk Polarinstitutt Skrifter, 154D. & WORSLEY, D. 1975. Observations on the Upper Palaeozoic stratigraphy of the Ny Friesland area. Norsk Polarinstitutt Arbok 1973, 41-51. -& YOCHELSON, E. L. 1982. Salterella rugosa (Early Cambrian: Agmata) on Nordaustlandet and Spitsbergen, Svalbard. Polar Research, 1, 1-15. , ANDRESEN, A., SALVIGSEN, O. • WINSNES, T. S. 1989. Geological Map of Svalbard 1:I00000 Sheet C8G Billefjorden (text). Norsk Polarinstitutt Temakart No. 5. --, SALVlGSEN,O. & WINSNES, T. S. 1989. Geological Map of Svalbard, I:100000, Sheet C8G, BilleJjorden. Norsk Polarinstitutt, Temakart No. 5. LAUSBERG, K. 1913. Das Nordland. Leipzig. LAVRUSHIN, Y. A. 1967. [The Pleistocene of Northern Spitsbergen (Vestspitsbergen)]. Doklady Akademii Nauk SSSR, 176, 167-170 [in Russian]. - - 1 9 6 9 . Stratigraphy of Quaternary deposits and some questions of the palaeogeography of Spitsbergen. In: Quaternary deposits of Spitsbergen, 8th INQUA Conference, Paris. Publ. M., 144-147. - - 1 9 6 9 . [Quaternary deposits' of Spitsbergen]. Izdatel'stvo 'Nauka', Moscow. - - 1 9 7 0 . [Questions of the stratigraphy and palaeogeography of Spitsbergen in the Late Pleistocene]. In: TOLMACnEV,A. I. (ed.) The Arctic Ocean and its coast during the Cenozoic. NIIGA, Leningrad and Amerind, New Delhi (1982), 53-56. , DEVmTS, A. L., DOBKINA, E. I., ZAVEL'SKrV, F. S. & FOROVA, V. S. 1968. [Pleistocene stratigraphy of Spitsbergen]. Doklady Akademii Nauk SSSR, 181, 178-181, [translation in Doklady of the Academy of Sciences of the USSR, Earth Sciences Sections, 181(1-6), 24-27]. LAZUTKrNA, O. F. & GORYL~NOVA,R. V. 1972. [New early Permian bryozoa from Spitsbergen, the Pamirs and Darvaza]. In: Novyye vidy drevnikh rasteniy i bespozvonochnykh SSSR. Akad. Nauk SSSR, Moscow, 166-168. LE PICHON, X., SmUET, J.-C. & FRANCHETAU,J. 1977. The fit of the continents around the North Atlantic Ocean. Tectonophysics, 38, 169-209. LEBESaYE, E. & VORREN, T. O. 1996. Submerged terraces in the southwestern Barents Sea: origin and implications for the late Cenozoic geological history. Marine Geology, 130, 265-280. LEE, G. W. 1908. Notes on fossils from Prince Charles Foreland. Proceedings of the Royal Physical Society of Edinburgh, 17, 149-166. - - 1 9 1 2 . Notes on Arctic Palaeozoic fossils from the "Hecla" and "Fury" collections. Proceedings of the Royal Physical Society of Edinburgh, 18-19, 255-264. LEEDER, M. R. & GAW'rHORPE, R. L. 1987. Sedimentary models for extensional tiltblock/half-graben basins. In: COWARD,M. P. DEWEY, J. F. & HANCOCK,P. L. (eds) Continental Extensional Tectonics. Special Publications Geological Society, London, 28, 139-152. LEFAUCO~rNIER, B. & HAGEN, J. O. 1990. Glaciers and climate in Svalbard: statistical analysis and reconstruction of the Broggerbreen mass balance for the last 77 years. Annals of Glaciology, 14, 148-152. 1

-

-

:

498

REFERENCES

& 1991. Surging and calving glaciers in eastern Svalbard. Norsk Polarinstitutt Meddelelser 116. - - , - - & RUDANT, J. P. 1994. Flow speed and calving rate of Kongsbreen glacier, Svalbard, using SPOT images. Polar Research, 13, 59-65. LEHMAN,J. P. 1947. Un nouvel Amiide de l'Eocene du Spitsberg, Pseudamia heintzi. In: Naturhistorisk Avd. 39. Tromso Museums ,4rshefter 70(2). - - 1 9 7 0 . L'exprdition palrontologique francaise de 1969 au Spitzberg. Atomes, 25, 193-198. LEHMAN, U. 1981. The Ammonites. Cambridge University Press. , THIEDIG,F. & HARLAND,W. B. 1978. Spitzbergen im Terti/ir. Polarforschung, 48, 120-138. LHTH, L. 1990. Shallow Drilling Bjornoya West 1989. Appendix Volume 3 - Organic Geochemical Data (Report 21..3465). IKU. , WEISS, H. M., MORK, A., ARHUS, N., ELVEBAKK,G., EMBRY, A. F., BROOKS, P. W., STEWART, K. R., PCHELINA, T. M., BRO, E. G., VERBA, M. L., DANYUSHEVSKAYA, A . &: BORISOV, A. V. 1993. Mesozoic hydrocarbon sourcerocks of the Arctic region. In: VORREN, T. O. et al. (eds) Arctic Geology and Petroleum Potential, NPF Special Publication, 2. Elsevier, Amsterdam, 1-25. LEPVR1ER,C. 1988. Relais compressifs et distensifs entre drcrochements dans la chaine tertiaire du Spitzberg (Svalbard, Norvege) Comptes Rendus de l'Academie des Sciences, Paris (Series II), 307, 409-414. - - 1 9 9 0 . L'l~volution tectonique de la chaine Tertiaire du Spitsberg. lnter-nord, 19, 455-464. --1992. Early Tertiary palaeostress distribution on Spitsbergen: implications for the tectonic development of the western fold-and-thrust belt. In: DALLMANN,W. K., ANDRESEN, A. & KRILL, A. (eds) Post-Caledonian Tectonic Evolution of Svalbard. Norsk Geologisk Tidsskrift, 72, 129-135. - - 1 9 9 4 . The origin of the West Spitsbergen fold belt from geological constraints and plate kinematics: implications for the A r c t i c - comment. Tectonophysics, 234, 329-333. - • GEYSSANT,J. 1984. Tectonique cassante et champs de contrainte tertiaires le long de la marge en coulissement du Spitsberg: corrrlations avec les mrchanismes d'ouverte de lamer de Norvrge-Gro6nland. Annales de la SociOtO G~ologique du Nord, 103, 333-344. - & 1985. L'evolution structurale de la marge occidentale du Spitsberg: coulissement et rifting tertiares. Bulletin de la Soci~t~ Gdologique de France, 8, 115-125. , LEPARMENTIER,F. & SELAND,R. 1988. Tertiary stress evolution on Svalbard. In: DALLMANN, W. K., OHTA, Y. & ANDRESEN, A. (eds) Tertiary Tectonics of Svalbard. Norsk Polarinstitutt, Report Series, 46, 59-62. ----orw--~r &Na_ 1989. Upper Palaeozoic faulting regimes in Bjornoya (Svalbard, Bulletin de la Soci~t~ G~ologique de France, 5, 411-417. LEVESBYE,E. & VORREN, T. O. 1996. Submerged terraces in the southwestern Barents Sea: origin and implications for the Late Cenozoic geological history. Marine Geology, 130, 265-280. LEYTHAEUSER,D., MACKENZIE,A. S., SCHAEFEER,R. G., ALTEBAUMER,F. J. & BJOROY, M. 1983. Recognition of migration and its effects within two coreholes in shale/ sandstone sequences from Svalbard, Norway. In: BJOROY,M. et al. (ed.) Advances in Organic Geochemistry 1981. Wiley, New York, 136-146. LIESTOL, O. 1962. Talus terraces in Arctic regions. Norsk Polarinstitutt ,4rbok 1961, 10~105. - - t 9 6 9 . Glacier surges in West Spitsbergen. Canadian Journal of Earth Sciences, 69, 895-897. - - 1 9 7 2 . Submarine moraines of the west coast of Spitsbergen. Norsk Polarinstitutt ,4rbok, 1910, 165-168. - - 1 9 7 6 . [Annual moraines in front of Nathorstbreen?]. Norsk Polarinstitutt Arbok 1976, 361-363. - - 1 9 7 7 . Pingos, springs and permafrost in Spitsbergen. Norsk Polarinstitutt Arbok 1975, 7-29. - - 1 9 8 6 . Glaciological investigations in the balance year 1983-84. Polar Research, 4, 97-101. - - 1 9 9 3 . Glaciers of Svalbard. In: WILLIAMS, R. S. JR. d~; FERRIGNO, J. G. (eds) Satellite Image Atlas of GIaciers of the World. US Geological Survey Professional Papers, 1386E. LILJEQUIST, G. H. 1958. Swedis~Finnish-Swiss International Geophysical Year Expediton to Nordaustlandet 1957-1958. Operations in 1957. Polar Record, 9, 24-25. LINDNER, L., MARKS, L. t~; SZCZESNY,R. 1986. Late Quaternary tectonics in western Sorkapp Land, Spitsbergen. Acta Geologica Polonica, 36, 281-288. LINDSTROM, G. 1865. Om Trias- och Jura-f/Srsteningar frfin Spetsbergen. Kungliga Svenska Vetenskapsakademiens Handlingar, 6, 1-20. - - 1 8 9 9 . On a species of Tetradium from Beeren Eiland. Kungliga Svenska Vetenskapsakademiens O]vers. Arg., 56, 41 47. - - 1 9 0 0 . On Thecocyathus nathorsti n. Sp., a Neocomian coral from King Charles Land. Kungliga Svenska Vetenskapsakademiens Handlingar, 57, 5 12. LISZKA, S. 1964. Occurrence of Lower Permian foraminifers in the Treskelodden Beds of Hornsund, Vestspitsbergen. In: BIRKENMAJER,K. (ed.) Geological Results of the Polish 1957-1958 1959, 1960 Spitsbergen Expeditions, Part 3. Studia Geologica Polonica, ll, 169-172. L~TVIN, V. M. 1965. [Origin of the bottom configuration of the Norwegian sea]. Okeanologiya A N SSSR, 5, 90-96 [translated for American Geophysical Union]. LIVSHITS,YU. YA. 1964. [Tectonics of the central part of Vestspitsbergen]. In: SOKOLOV, V. N. (ed.) Conference on the Geology of Spitsbergen, Leningrad 1964: Summary of Contributions. NIIGA, Leningrad, 17-20. - - 1 9 6 4 . [Palaeogene rocks of the area Isfjorden to Van Mijenfjorden]. In: SOKOLOV, V. N. (ed.) Conference on the Geology of Spitsbergen, Leningrad 1964: Summary of Contributions. NIIGA, Leningrad, 12-15. --

- - 1 9 6 4 . [Results of the conference on Spitsbergen. Geology, 26-27 March 1964]. Uchenyye Zapiski NIIG. Paleontologiya i Biostratigrafiya, 4. Recorded Studies of Regional Geology. NIIGA, Leningrad, 265-270. - - 1 9 6 5 . [Tectonics of central Vestpitsbergen]. In: SOKOLOV,V. A. (ed.) Materialy po Geologii Shpitsbergena. NIIGA, Leningrad, 55-70. - - 1 9 6 5 . [Palaeogene deposits of Nordenski61d Land, Vestspitsbergen]. ln: SOKOLOV, V. N. (ed.) Materialy po Geologii Shpitsbergena. NIIGA, Leningrad, [trans. 1970] 185-208. - - 1 9 6 5 . [Conference on the geology of the Spitsbergen archipelago]. Sovetskaya Geologiya, 4, 150-155. - - 1 9 6 6 . [New data on the geological structure of the Pyramiden area (Vestspitsbergen)]. Uchenyye Zapiski NIIGA: Regional'naya Geologiya, 9, 36-56. - - . 1 9 6 7 . Tertiary deposits in the western part of the Spitsbergen archipelago. In: SOKOLOV,V. N. (ed.) Materialy po stratigrafi Shpitsbergena. NIIGA, Leningrad, 1 8 5 -204. --1970. [Main stages in the formation of the platform structures of Spitsbergen]. In: Materials for the First Scientific Conference of Leningrad Geological Research Students (9-10 February 1970). VSEGEI, Leningrad, 8-10. - - 1 9 7 4 . Palaeogene deposits and the platform structure of Svalbard. Norsk Polarinstitutt Skrifter, 159, 1-51. - - 1 9 9 2 . Tectonic history of Tertiary sedimentation of Svalbard. In: DALLMANN, W. K., ANDRESEN, A. & KRILL, A. (eds) Post-Caledonian Tectonic Evolution of Svalbard. Norsk Geologisk Tidsskrift, 72(1), 121-128. - & PCHELINA,T. M. 1972. [The stratigraphy of the Mesozoic and Early Cenozoic of Spitsbergen]. In: The Stratigraphy, Palaeogeography and Useful Minerals of the Soviet Arctic. A Collection of Articles. NIIGA, Leningrad, 44-54. - - 1 9 3 7 . [Geology of the Tertiary coal-bearing deposits of Spitsbergen in the Isfjorden region]. Trudy Arkticheskogo Instituta, 76, 7-24 [in Russian with English summary]. LLOYD, J. M., KROON, D., BOULTON,G. S., LABAN,C. & FALLICK,A. 1996. Ice rafting history from the Spitsbergen ice cap over the last 200 kyr. Marine Geology, 131, 103-121. LOCK, B. E., PICKTON,C. A. G., SMITH,D. G., BATTEN,D. J. & HARLAND,W. B. 1978. The geology of Edgeoya and Barentsoya, Svalbard. Norsk Polarinstitutt Skrifter, 168, 1-64. LOFALDLI, M. 1978. Early Cretaceous foraminifera from the JanusfjeUet Formation in Kong Karls Land, eastern Svalbard. Norsk Polarinstitutt Arbok, 1977, 345-350. - & NAGV, J. 1980. Foraminiferal stratigraphy of Jurassic deposits on Kongsoya, Svalbard. Norsk Polarinstitutt Skrifter, 172, 63-95. - & - - 1 9 8 3 . Agglutinating foraminifera in Jurassic and Cretaceous dark shales in southern Spitsbergen. In: VERDENIUS,J. G., VAN HINTE, J. E. & FORTUIN,A . R. (eds) Proceedings of the First Workshop on Arenaceous Foraminifera, 7-9 September 1981. IKU, Publications, 108, 91-107. -& THUSU, B. 1977. Microfossils from the Janusfjellet Subgroup (Jurassic-Lower Cretaceous) at Agardhfjellet and Keilhaufjellet, Spitsbergen. Norsk Polarinstitutt ,4rbok 1975, 69 77. LOGAN, A. 1966. The Upper Palaeozoic productoid brachiopod Horridonia timanica (Stuckenberg) and its close relatives. Transactions of the Leeds Geological Society, 7, 193-210. LONG, J. A. 1993. Morphological characteristics of Paleozoic vertebrates used in biostratigraphy. In: LONG, J. A. (ed.) Palaeozoic Vertebrate Biostratigraphy. Belhaven Press, London, 3-24 LONNE, I. 1997. Facies characteristics of a proglacial turbiditic sand-lobe at Svalbard. Sedimentary Geology, 109, 13-35. LONOY, A. 1988. Environmental setting and diagenesis of Lower Permian palaeoaplysinid build-ups and associated sediments from Bjornoya: implications for the exploration of the Barents Sea. Journal of Petroleum Geology, 11, 141-156. - - 1 9 9 5 . A mid-Carboniferous carbonate platform, Central Spitsbergen. Norsk Geologisk Tidsskrift, 75, 48 63. LOSETH,H., LIPPARD,S. J., SiETTEM,J., FANAVOLL,S., FJERDINGSTAO,V., LEITH,L. T., RITTER, U., SMELROR, M. t~ SYLTA, O. 1990. Cenozoic uplift and erosion of the Barents S e a - evidence from the Svalis Dome area. Report 23.9011.03/HL/ame, IKU, Trondheim. LOTZE, F. & SCHMIDT,K. (eds) 1966. Prdkambrium. Handbuch der Stratigraphischen Geologi, Part 13, F. Enke, Stuttgart. LOVLIE, R., SVENDSEN, J. I. & MANGERUD, J. 1991. High-latitude Holocene paleosecular variation and magneto-stratigraphic correlation between two lakes on Spitsbergen (78~ Physics of the Earth and Planetary Interiors, 67, 348-361. --, TORSVIK, T., JELENSKA, M. & LEVANDOWSK1,M. 1984. Evidence for detrital remanent magnetization carried by hematite in Devonian red beds from Spitsbergen: palaeomagnetic implications. Geophysical Journal of the Royal Astronomical Society, 79, 573-588. LOWELL, J. D. 1968. Upper Palaeozoic and Lower Mesozoic stratigraphy of southwestern Nordaustlandet, Spitsbergen. Geological Magazine, 105, 348 355. - - 1 9 7 2 . Spitsbergen Tertiary orogenic belt and the Spitsbergen fracture zone. Geological Society of America Bulletin, 83, 3091-3101. LowY, J. 1949. A labyrinthodont from the Trias of Bear Island, Spitsbergen. Nature, 163, 1002. Lu, S. R. 1985. [Tectonic evolution of Spitsbergen in the Arctic]. Journal of Wuhan College of Geology, Earth Science, 10, 49-56 [in Chinese]. LUBER, A. A. 1935. Les types petrographiques de charbons fossiles du Spitsbergen. Chimie Combustible Solide, 5, 186-195. LUDWIG, P. 1989. Depositional environment in the Middle Carboniferous of the Broggerhalvoya (Svalbard)- facies and tectonic interpretation of sedimentary sequences. Polarforschung, 59, 79-99.

REFERENCES - - 1 9 9 0 . Petrographic und Entwicklung yon Calcrete in mittelkarbonen Alluvial Fans auf Spitzbergen (Norwegen). Neues Jahrbuchffir Geologic und Palaontologie, Monatschefte 1990, 109 119. - - 1 9 9 1 . The marine transgression in the Middle Carboniferous of Broggerhalvoya (Svalbard). Polar Research, 9, 65-76. LUONSKAYA, T. N. & TROITSKIY, L. S. 1972. [On the diagnostics of glacial and glaciomarine deposits and forms of relief in Spitsbergen]. Materialfi glaciology issledovano" Chronika, Obsurdeniya, Moscow, 160-165. LUNCKE, B. 1949. [Norway's Svalbard and Arctic" Ocean mapping and the application to it ofaerialphotogrammetry]. Norsk Polarinstitutt Meddelelser, 68. LUNDE, T. 1965. Ice conditions at Svalbard 1946-1963. Norsk Polarinstitutt Arbok, 61-80. LUNDGREN, B. 1883. Bemerkungen fiber die yon der schwedischen Expedition nach Spitzbergen 1882 gesammelten Jura- und Trias-Fossilien. Bih. Kungliga Svenska Vetenskapsakademiens Handlinger, 8. Uppsala & Stockholm. LUNDGREN, B. 1887. Anmdirkningar om Permfossil frdn Spetsbergen. Bih. Kungliga Svenska Vetenskapsakademiens Handlinger, 13. Uppsala & Stockholm. LUSSJAA-BERDOV-POLU~,M. & VIDAC, P. 1973. Initial strontium isotopic composition of volcanic rocks from Jan Mayen and Spitsbergen. Earth and Planetary Science Letters, 18, 33. LYBERIS, N. & MANBY, G. M. 1993a. The West Spitsbergen Fold Belt: the result of Late Cretaceous-Palaeocene Greenland-Svalbard convergence? Geological Journal, 28, 125 136. & 1993b. The origin of the west Spitsbergen Fold Belt from geological constraints and plate kinematics: implications for the Arctic. Tectonophysics, 224, 371-391. -& - - 1 9 9 4 . The origin of the West Spitsbergen fold belt from geological constraints and plate kinematics: implications for the Arctic - reply to comment. Tectonophysics, 234, 334-337. --, -& TH1EDI~, F. 1992. The West Spitsbergen Fold Belt: the result of Late Cretaceous-Palaeocene Greenland-Svalbard convergence? (abstract). Norsk Geologisk Tidsskrift, 72, 137. LYCKE, A. 1987. Foraminferal stratigraphy as a method for the correlation of Weichselian sedimentology along the west coast of Spitsbergen (abstract). In: lOth Conference of the Norwegian Geological Society. N.G.F., Trondheim, 138. LYTSKJOLD, B. E. 1991. Magnetic Survey in Svalbard 1985-1987. Norsk Polarinstitutt Meddelelser 114. LYUBER, A. A. 1935. [Petrographical types of coal mined in the island of Spitsbergen]. Khimiya Tverdogo Topliva, 4, 186-195. LYUTKEVICH,YE. M. 1937a. [Geological survey and the problems of the coal fields of Mount Pyramid, Spitsbergen]. Trudy Arkticheskogo Instituta, 76, 25-38 [English summary]. - - 1 9 3 7 b . [Geology of the Tertiary coal-bearing deposits of the Isfjorden region of Spitsbergen]. Trudy Arkticheskogo Instituta, Leningrad, 76, 7-24. MACHEK, P. 1978. Nansenia, n.g. new bivalve genus from the Devonian of Spitsbergen. Sbornik vedeckych praci Vysoke skoly banske v Ostrave Rocnik, 24, 113-142. MACHERET, Y. Y. & ZHURAVLEV, A. B. 1982. Radio-echo sounding of Svalbard glaciers. Journal of Glaciology, 28, 295 314. MADERA, E. & O'Cor,VNELL,S. 1995. Pliocene-Pleistocene glacial history of the Yermak Plateau, western Spitsbergen. Geological Society of America, Abstracts with programs, 27, 66. MAHER, H. D. JR.. 1988. Minimum estimate of Tertiary shortening suggested by surface structures exposed on Midterhuken, Bellsund, Spitsbergen. In: DALEMANN, W. K., OHTA, Y. & ANDRESEN, A. (eds) Tertiary Tectonics of Svalbard. Norsk Polarinstitutt, Report Series, 46, 35-38. - - 1 9 8 8 . Photointerpretation of Tertiary structure in platform cover strata of interior Oscar II Land, Spitsbergen. Polar Research, 6, 155 172. --1989. A storm-related origin for the Jurassic Brentskardhaugen Bed of Spitsbergen, Norway. Polar Research, 7, 66-77. & CRADDOCK,C. 1988. Decoupling as an alternate model for transpression during the initial opening of the Norwegian Greenland Sea. Polar Research, 6, 137 140. & WELBON, A. I. 1992. Influence of Carboniferous structures on Tertiary tectonism at St Jonsfjorden and Bellsund, western Svalbard. In: DALLMANN, W. K., ANDRESEN, A. & KRILL, A. (eds) Post-Caledonian Tectonic Evolution of Svalbard. Norsk Geologisk Tidsskrift, 72, 67-76. , BERGH, S., BRAATHEN, A. & OHTA, A. 1997. Svartfjella, Eidembukta, and Daudmannsodden" Tertiary orogen-parallel motion in the crystalline hinterland of Spitsbergen's fold-thrust belt. Tectonics, 6, 88-106. - - , BRAATHEN,A., BERGH, S., DALLMANN,W. ~; HARLAND, W. B. 1995. Tertiary or Cretaceous age for Spitsbergen's fold-thrust belt on the Barents shelf. Tectonics, 14, 1321-1326. - - , CRADDOCK,C. & MAHER, K. A. 1986. Kinematics of Tertiary structures in upper Paleozoic and Mesozoic strata of Midterhuken, west Spitsbergen. Geological Society of America Bulletin, 97, 1411-1421. - - , RINGSET,N. & DALLMANN,W. K. 1989. Tertiary structures in the platform cover strata of Nordenskirld Land, Svalbard. Polar Research, 7, 83-93. MAINKA, C. 1914. Ergebnisse der Erdbebenstation Adventbay auf Spitzbergen in der Zeit vom 27. Oktober 1911 bis 18. Juni 1912. Gerlands Beitrage zur Geophysik., 13, 103-113. MAJOR, H. 1955. Ordovician cephalopods. In: MAJOR, H. & WINSNES, T. S. (eds) -

-

-

-

-

-

Cambrian and Ordovieian fossils from Sorkapp Land, Spitsbergen. Norsk Polarinstitutt Skrifter, 106, 31-47. - - 1 9 6 5 . Kartbladet Adventdalen, Svalbard (abstract). Geologi (Helsinki), 17, 137. & NAGY, J. 1964. [Adventdalen Geological map]. Norsk Polarinstitutt Meddeleser. -& 1972. Geology of Adventdalen map area. Norsk Polarinstitutt Skrifter, 138, 1 58 (with 1:100 000 geological sheet C9G).

499

& WINSNES, T. S. (eds) 1955. Cambrian and Ordovieianfossils from Sorkapp Land, Spitsbergen. Norsk Polarinstitutt Skrifter, 106, 1-47. , HARLAND, W. B. & ST~NI~, T. 1956. Dictionary of Geological Formations in Svalbard. In: Lexique Stratigraphic International, 1 (Europe), Paris, 919-925. , NAGY, J., HAREMO,P., DALLMANN,W. K., ANDRESEN, A. & SALV~GSEN,O. 1992. Geological Map of Svalbard. 1:100000, Sheet C9G. Adventdalen: Preliminary edition. (Revised after MAJOR, H. & NAVY, J. 1964) Norsk Polarinstitutt. MAKAR'EV, A. A., HAJLOV, V. V. et al. 1996. Report on specialized geologicalgeophysical exploration, aimed at the study of geological structure and mineral occurrences of Spitsbergen in 1988-1991. In: KRASIL'SHCHIKOV,A. A. (ed.) Soviet Geological Research in Svalbard 1962-1992. Norsk Polarinstitut Meddelelser, 139, 97. MALECK~, J. 1968. Permian bryozoans from the Tokrossoya beds, Sorkappland, Vestspitsbergen. Studia Geologica Polonica, 21, 7-32. - - 1 9 7 3 . [Permian bryozoans from Spitsbergen]. Przeglad Geologiczny, 20, 410 [abstract, in Polish]. - - - 1 9 7 7 . Permian bryozoans from southern Spitsbergen and Bjornoya (Svalbard). Studia Geologica Poloniea, 51, 75-87. MALWA, R. G., KNOLL, A. H. & SIEVER, R. 1989. Secular change in chert distribution: a reflection of evolving biological participation in the silica cycle. Palaios, 4, 519 532. MALKOWSKI,K. 1982. Development and stratigraphy of the Kapp Starostin Formation (Permian) of Spitsbergen. In: BIERNAT, G. & SZYMANSKA,W. (eds) Palaeontological Spitsbergen Studies. Palaeontologica Polonica, 43, 69-81. - - 1 9 8 8 . Paleoecology of Productacea (Brachiopoda) from the Permian Kapp Starostin Formation, Spitsbergen. Polish Polar Research, 9, 3-60. & HOFVMAN,A. 1979. Semi-quantitative facies model for the Kapp Starostin Formation (Permian), Vestspitsbergen. Acta Palaeontologica Poloniea, 24, 217 230. & SZAMAWSKLH. 1976. Permian conodonts from Spitsbergen and their stratigraphic significance; a preliminary note. Norsk Polarinstitutt Arbok 1975, 79-83. --, GRUSZCZYNSKI,M. & HOFFMAN, A. 1991. A facies geological test of stable isotope interpretation of the Upper Permian depositional environment in West Spitsbergen. Terra Nova, 3, 631-637. & HALAS, S. 1989. Oceanic stable isotope composition and a scenario for the Permo-Triassic crisis. Historical Biology, 2, 289-309. MALOD, J. & MASCLE, J. 1975. Structures geologiques de la marge continentale a l'ouest du Spitsberg. Marine Geophysical Researches, 2, 215-229. MALOVITSKY, YA. P. • MATIROSSYAN, V. N. 1995. The Barents Shelf investigations: main results. In: HANSHEN, S. (ed.) Petroleum Exploration and Exploitation in Norway. NPF Special Publication, 4, Elsevier, 321 331. MANBY, G. M. 1978. Aspects of Caledonian metamorphism in central western Svalbard with particular reference to the glaucophane schists of Oscar II Land. Polarforschung, 48, 92-102. - - 1 9 8 3 . Primary scapolite from the Forland complex of Prins Karls Forland, Svalbard. Mineralogical Magazine, 47, 89 93. - - 1 9 8 3 . A re-appraisal of chloritoid-bearing phyllites in the Forland Complex of Prins Karls Forland, Svalbard. Mineralogical Magazine, 47, 311 318. - - 1 9 8 6 . Mid-Paleozoic metamorphism and polyphase deformation of the Forland Complex, Svalbard. Geological Magazine, 123, 651-663. - - 1 9 8 8 . Tertiary folding and thrusting in NW Svalbard. In: DALLMANN, W. K., OHTA, Y. & ANDPd~SEN, A. (eds) Tertiary Tectonics of Svalbard. Norsk Polarinstitutt, Report Series, 46, 17-20. - - 1 9 9 0 . The petrology of the Harkerbreen Group, Ny Friesland, Svalbard: protoliths and tectonic significance. Geological Magazine, 127, 129-146. & HAMBREY, M. J. 1989. The structural setting of the Late Proterozoic tillites of East Greenland. In: GAYER, R. A. (ed.) The Caledonide Geology of Scandinavia. Graham & Trotman, London, 257-262. -& LYBERIS,N. 1991. Contrasting tectono-metamorphic terranes in NE Svalbard: Sm/Nd-Rb/Sr isotopic and structural constraints. In: Terranes in the Arctic Caledonides, Tromso, 12-16 August 1991. Terra Abstracts, 4, 22-23. & 1992. Tectonic evolution of the Devonian basin of northern Svalbard. In: DALLMANN, W. K., ANDRESEN, A. & KRILL, A. (eds) Post-Caledonian Tectonic Evolution of Svalbard. Norsk Geologisk Tidsskrift, 72, 7-20. -& 1995. Discussion on the Ny Friesland Orogen, Spitsbergen. Geological Magazine, 132, 351-356. & 1996. State of stress and tectonic evolution of the West Spitsbergen Fold Belt. Tectonophysics, 267, 1-29. & MORRIS, A. P. 1981. The Mid-Palaeozoic Orogen of Svalbard: an example of gravity inversion tectonics? (abstract). In: March Meeting in Leeds. TSG, Leeds. - - , LYBER1S,N., CHOROW~CZ,J. & THIEDtG, F. 1994. Post-Caledonian tectonics along the Billefjorden fault zone, Svalbard, and its implications for the Arctic region. Geological Society oJ'America Bulletin, 105, 201-216. MANECKX, M. 1987. Prehnite occurrences in dolerite dikes of SW Spitsbergen (WedelJarlsberg Land). Mineralogia Polonica, 18, 79 86. MANGERUD, G. 1992. Palynostratigraphy of the Triassic succession, western Barents Sea. In: Suppl. 25-27 May 1992, Acadia University, Nova Scotia. Geological Association of Canada, Mineralogical Association of Canada, Abstracts with Programs, 17, A73. & KONIECZNY,R. M. 1991. Palynological investigations of Permian rocks from Nordaustlandet, Svalbard. Polar Research, 9, 155-168. & KONIECZNY,R. M. 1993. Palynology of the Permian succession of Spitsbergen, Svalbard. Polar Research, 12, 65-93. -& SALVIGSErq,O. 1984. The Kapp Ekholm section, Billefjorden, Spitsbergen: a discussion. Boreas, 15, 51-59. - - , BOLSTAD,M., ELGERSMA,A., HELLIKSEN,D., LANDVIK,J. Y., LONNE, L., LYECKE, A. K., SALW~SEN, O., SA~DAHL, T. & SVENDSEN, J. I. 1992. The last glacial maximum on Spitsbergen. Quaternary Research, 38, 1-31. --

-

-

-

-

-

-

-

-

-

-

-

-

-

-

500

REFERENCES

, JANSEN, E. & LANDVIK,J. Y. 1996. Late Cenozoic history of the Scandinavian and Barents Sea ice sheets. In: SOLHEIM, A. et al. (eds) Global and Planetary Change, 12, 11-26. MANN, A. & TOWNSEND, C. 1989. The post-Devonian tectonic evolution of southern Spitsbergen illustrated by structural cross-sections through Bellsund and Hornsund. Geologieal Magazine, 126, 549-566. MANSFIELD, E. 1919. Spitsbergen. Mining Magazine, 21, 95-97. MANUM, S. 1954. [Spores and pollen from Tertiary coal of Vestspitsbergen]. Norsk Polarinstitutt Meddelelser, 79. - - 1 9 5 5 . Spitsbergen Tertiary coal fossils (abstract). Nature, 176, 248-249. - - 1 9 5 6 . A palynological investigation of Tertiary coals from West Spitsbergen. In: Congr. Int. Bot. 8me, Paris 1954, (Rappt. Commun., Sections 3-6), 254-255. - - 1 9 6 0 . Some dinoflagellates and hystriehosphaerids from the Lower Tertiary of Spitsbergen. Norsk Polarinstitutt Meddelelser, 85. - - 1 9 6 2 . Studies in the Tertiary flora of Spitsbergen with notes on Tertiary floras of Ellesmere Island, Greenland and Iceland. Norsk Polarinstitutt Skrifter, 125, 1-127. 1963. Notes on the Cretaceous-Tertiary boundary in Basilika, Vestspitsbergen, and a new record of Ginko from the Spitsbergen Tertiary. Norsk Polarinstitutt Arbok 1962, 149-152. - - 1 9 6 6 . Ginkgo spitsbergensis n. sp. from the Paleocene of Spitsbergen and a discussion of certain Tertiary species of Ginko from Europe and North America. Norsk Polarinstitutt .4rbok 1965, 49-58. & THRONDSEN, T. 1978a. Rank of coal and dispersed organic matter and its geological bearing in the Spitsbergen Tertiary. Norsk Polarinstitutt Arbok 1977, 159-177. & 1978b. Dispersed organic matter (kerogen) in the Spitsbergen Tertiary. Norsk Polarinstitutt ftrbok 1977, 179-187. & 1986. Age of Tertiary formations on Spitsbergen. Polar Research, 4, 103-131. , BJAERKE, T., THRONDSEN,T. & LIEN, M. 1977. Preservation and abundance of palynomorphs, and observations on thermal alteration in Svalbard. Norsk Polarinstitutt Arbok 1976, 121-130. MARINCOVICH, L., BROUWERS, E. M. & CARTER, L. D. 1985. Early Tertiary marine fossils from northern Alaska: implications for Arctic Ocean palaeogeography and faunal evolution. Geology, 13, 770-773. MARSCHALL, A. G. von 1875. Note on the transition from Carboniferous to Permian. Geological Magazine, N.S. Dec. II, 272. MARINCOVTICH,L. J. & ZINSMEISTER,W. J. 1991. The first Tertiary (Paleocene) marine molluscs from the Eureka Sound Group, Ellesmere Island, Canada. Journal of Palaeontology, 65, 24~248 (Abstract). MATISHOV,G. G. 1977. [Bottom morphology and the problem of Pleistocene glaciation of the Barents Sea Shelf]. Geomorphology, 2, 91 98. MAX, M. D. & LOWRIE, A. 1993. Natural gas hydrates: Arctic and Nordic Sea Potential. In: VORREN, T. O. et al. (eds) Arctic Geology and Petroleum Potential. Elsevier, 27-53. & OIqTA,Y. 1988. Did major fractures in continental crust control orientation of the Knipovich Ridge-Lena Trough segment of the plate margin? Polar Research, 6, 85-93. MAZIN, J.-M. 1981. Grippia longirostia Wiman, 1929, un Ichthyopterygia primitif du Trias inf6rieur du Spitsberg. Bulletin of the British Museum (Natural History), Geology, C3, 317-340. McCABE, L. H. 1939. Nivation and corrie erosion in West Spitsbergen. Geographical Journal 94, 447-465. McCANN, A. J. 1996. Timing of basement deformation in NW Svalbard - Evidence from Devonian unconformities. In: Unconformities and Tectonic Events Program with Abstracts. Tectonic and Structural Geology Study Group Meeting 7-8 November 1996. Norwegian Geological Society, University of Oslo. 8z DALLMANN, W. K. 1995. Multiple tectonic event history of the Billefjorden Fault Zone in north central Spitsbergen, Svalbard. Geological Magazine, 133, 63-84. MCKENZIE, D. 1978. Some remarks on the development of sedimentary basins. Earth and Planetary Science Letters, 40, 25 32. MCKERROW, W. S. &; COCKS, C. R. M. 1976. Progressive faunal migration across Iapetus Ocean. Nature, 263, 304-306. , SCOTESE, C. R. & BRASIER, M. D. 1992. Early Cambrian continental reconstructions. Journal of" the Geological Society, London, 149, 599 606. MCWHAE, J. R. H. 1953. The major fault zone of central Vestspitsbergen. Quarterly Journal of the Geological Society of London, 108, 209-232. - - 1 9 5 3 . The Carboniferous breccias of Billefjorden, Vestspitsbergen. Geological Magazine, 90, 287-298. - - 1 9 8 6 . Tectonic history of northern Alaska, Canadian Arctic, and Spitsbergen regions since Early Cretaceous. Bulletin of the American Association of Petroleum Geologists, 70, 430-450. MEHLUM, F. 1990. The Birds and Mammals of Svalbard. Polarhandbook No. 5. Norsk Polarinstitutt, Oslo. MEIER, M. F. ~r POST, A. S. 1969. What are glacier surges? Canadian Journal of Earth Sciences, 6, 807-817. MENNER, V. V. 1960. On the nomenclature problem of the Upper Precambrian Group. -

-

-

-

-

-

-

-

MEUNIER, S. 1894. Note sur les 6chantillons g~ologiques recueillis par La Manche au cours de son voyage. In: Voyage de "La Manche'" a l'fle Jan-Mayen et au Spitzberg (juillet-aodt 1892). Nouvelles Archives Miss. Sci. Litt. Paris, 1894, 221-229. MEWIUS, F. 1900. Spitzbergens Steinkohlen. Berg- und hfittenmaennisches Zeitungs, 451-452. - - 1 9 0 1 . Deutsche Nutzbarmachung auf der B/ireninsel. Globus, 79, 236-239. MIALL, A. D. t984. Sedimentation and tectonics of a diffuse plate boundary: The Canadian Arctic Islands from 80 Ma B.P. to the present. Tectonophysics, 107, 261-277. MICHALSr,A, Z. 1968. Geological research in the frontal zone of Penckbreen, Van Keulenfjorden, Vestspitsbergen. In: BIRKENMAJER, K (ed.) Polish Spitsbergen Expeditions 195~1960. Polish Academy of Sciences, Warsaw, 371-375. MICHELSEN,J. K. & KHORASANI,G. K. 1991. A regional study of coals from Svalbard: organic facies, maturity and thermal history. Bulletin de la Soci~t~ GOologique de France, 162, 385-397. MIGALA, K. 8z SOBIK, M. 1982. Discovery of thermal springs in the Raudfjellet region, SW Spitsbergen. Polar Research, 2, 109-110. MII, H., GROSSMAN,E. ,~r YANCEY, T. E. 1997. Stable carbon and oxygen isotope shifts in Permian seas of West Spitsbergen-Global or diagenetic artifact. Geology, 25, 227-230. MIKHAYLOVA,N. S. & TURCHENKO,S. I. 1986. [Microfossils of the Late Precambrian of Spitsbergen and their stratigraphic significance]. Izvestiya AN SSSR, Seriya Geologicheskaya 1986, 18-25. MILLER, G. H. 1982. Quaternary depositional episodes, western Spitsbergen, Norway: aminostratigraphy and glacial history. Arctic and Alpine Research, 14, 321 340. MILLER, J. A. t~ HARLAND,W. B. 1963. Ages of some Tertiary intrusive rocks in Arran. Mineralogical Magazine, 33, 521-523. M1L'SHTEYN, V. YE. 1967. [New forms of oncolites from the Precambrian deposits of Spitsbergen]. In: SOKOLOV, V. N. (ed.) Materiali po stratigraphii Shpitsbergena. NIIGA, Leningrad, 21-35. --1976. [Vertical and areal distribution of microphytolites in the Upper Precambrian to Lower Cambrian deposits of northern Siberia and Bear and Spitsbergen Islands]. In: SOKOLOV, B. S. et al. (eds) Paleontology of the Precambrian and Early Cambrian. Papers presented at the All-Union Symposium, May 1976, Novosibirsk, 88-90. & GOLOVANOV,N. P. 1979. Upper Precambrian microphytolites and stromatolites from Svalbard. Norsk Polarinstitutt Skr!fter, 167, 219-224. & 1983. [The stratigraphic significance of the Upper Precambrian phytolites of Svalbard for interregional correlation]. In: KRASIL'SHCHIKOV,A. A. & BASOV, B. A. (eds) Geologiya Shpitsbergena: sbornik nauchnykh trudov [The Geology of Spitsbergen: a Collection of Papers]. "Sevmorgeo", Leningrad, 28-37. MILES, P. & WRIGHT, N. J. R. 1978. An outline of mineral extraction in the Arctic. Polar Record, 19, 11-38. MILOSLAVSKIY,M. Ju., BIRYUKOV,A. S., SLENSKIY,S. N., HANSEN, S., LARSEN, B. T., DALLMANN,W. K. 8r ANDRESEN, A. 1993. Geological Map of Svalbard. 1:100,000. Sheet D9G Agardhfjellet. Norsk Polarinstitutt, Temakart, 21. , __ , KRASIL'SHCHIKOV,A. A. 8/; DALLMANN,W. K. 1994. Geological Map of Svalbard, 1:100,000, sheet D8G, Negribreen Digital Version, NW 1994. Norsk Polarinstitutt. , DALLMANN,W. K. & SALVIGSEN,O. 1977. Geologicalmap of Svalbard 1:I00,000, Sheet D8G Negribreen text. Norsk Polarinstitutt. MISNIK, I. YU. & BELOUSOV,K. N. 1983. [Features of engineering geology conditions in the Soviet mining areas of Vestspitsbergen]. In: NEIZVESTNOV, YA. V. 8,:; SEMEVSKIY, D. V. (eds) Gidrogeologiya, Inzhenernaya Geologiya, Geomorfologiya 5 9 ,

1 1 - 1 4

-

-

In: International Geological Congress. Report of 21st Session, Part VIII, Late Precambrian and Cambrian Stratigraphy. International Geological Congress, Norden, 18-23. MERRIAM, J. C. 1911. Notes on the relationships of the marine Saurian described from the Triassic of Spitzbergen by Wiman. University of California Publication Department of Geology, 6, 317-327.

-

-

-

-

Arkhipelaga Shpitsbergen [The Hydrogeology, Engineering Geology and Geomorphology of the Spitsbergen Archipelago]. PGO "Sevmorgeo", Leningrad, 16-33. MITCHELL, B. J. & CHAN, W. W. 1978. Characteristics of earthquakes in the Heerland seismic zone of eastern Spitsbergen. Polarforschung, 48, 31 40. - - , BUNGUM,H., CHAN, W. W. & MITCHELL,P. B. 1990. Seismicity and present-day tectonics of the Svalbard region. Geophysical Journal International, 102, 139-149. --, VINCENZ, S. A., TEISSEYRE, R., GUTERCH, A., DUDA, S. J. & SELLEVOLL,M. A. 1978. Geophysical research in Spitsbergen. Arctic Bulletin, 2, 314-319. - - , ZOLLWEG,J. E., KOHSMANN,J. J., CHENG, C. C. & HAUG, E. J. 1979. Intraplate earthquakes in the Svalbard archipelago. Journal of Geophysical Research, 84, 5620-5627. MOIGN, A. 1966. Formes sous-marines et littorales de la Baie du Roi (Spitsberg). M~thodes d'~tude, aspects et problems. Bulletin de l'Association G~ographique de Fran;ais, 34~343, 11-24. MoJsxsovIcs VON MOJSVAR, E. 1874. 15ber die triadischen Pelecypoden-Gattungen Daonella und Halobia. Abhandlungen der Geologischen ReichsAnst, 7, 1-37. - - 1 8 8 6 . Arktische Triasfaunen. Beitrdge zur paldontoIogisehen Charakteristik der arktisch-pacifisehen Triasprovinz unter Mitwirkung der Herren Dr. Alexander Bittner und Friedrich Teller. M6moire de l'Acad6mie Imperiale des Sciences de St. P6tersbourg, 33, 1-159. MOKIN, J. I. 1996. Outline of the geology of northwestern Andr6e Land. In: KRASIL'SHCHIKOV,A. A. (ed.) Soviet Geological Research in Svalbard 1962-1992. Norsk Polarinstitut Meddelelser, 139, 33. & KOLESNIK, V. G. 1996. Outline of the geology of the Raudfjorden and Liefdefjorden areas. In: DALL~aANN, W. K. & KRASlL'SHCHIKOV,A. A. (eds). Meddelelser, 139, 32. MOLLER, P., SXUBDRUP, O. P. & KRONBORG, C. 1995. Late Weichselian to early Holocene sedimentation in a steep fjord/valley setting, Visdalen, Edgeoya, eastern Svalbard: Glacial deposits, alluvial/colluvial-fan deltas and spit-platforms. Polar Research, 14, 181-203.

-

-

REFERENCES MONACO, ALBERT LER, PRINCE SOUVERAINDE. 1912--1914. Rdsultats de Campagnes Scientifiques accomplis sur son yacht. Fascicles: XL, Isachsen 1912, topographical; XLI, Isachsen & Hoel 1913, general; XLII, Hoel 1914, geology & glaciers; XLIII, Schetetig 1912, "Formations primitives"; XIV, Holmsen 1913, botany and soil polygons; XV Emile Topsent. Monaco. MOLLMAN, B. 1900. Die Kohlenlager der B/ireninsel. GlfickauJ~ 36, 225-226. MONCRIEFF, A. C. M. 1989. The Tillite Group and related rocks of East Greenland: implications for Late Proterozoic palaeogeography. In: GAYER, R. A. (ed.) The Caledonide Geology of Scandinavia. Graham & Trotman, London, 285 297. MONJUVENT, G. 1966. Quelques observations sur le Quaternaire au Spitsberg (P6ninsule de BrOgger et Isfjord. In: Centre National de la Recherche Scientifique: Recherche Cooperative sur Programme, Spitsberg 1964 et premidres observations 1965 (ed.), Audin, Lyon, 93-109. MONTFORD, H. M. t970. The terrestrial environment during Upper Cretaceous and Tertiary times. Proceedings of the Geologists' Association, 81, 181-204. MOODY-STUART,M. 1966. High and low-sinuosity stream deposits, with examples from the Devonian of Spitsbergen. Journal of Sedimentary Petrology, 36, 1102 1117. MOORES, E. M. 1991. Southwest U.S.-East Antarctic (SWEAT) connection: A hypothesis. Geology, 19, 425-428. MORK, A. 1978. Observations on the stratigraphy and structure of the inner Hornsund area. Norsk Polarinstitutt Arbok 1977, 61 70. - - 1 9 8 7 . History of Bjornoya and geological setting. In: MORK, A. (ed.) Geological Excursion Guide to Bjornoya. IKU, Trondheim. - - 1 9 9 4 . Triassic transgressive-regressive cycles of Svalbard and other Arctic areas, a minor of stage subdivision. In: Gu~x, J. & BAUD, A. (eds) Recent developments on Triassic stratigraphy. Lausanne, 69-81. BJOROY,M. 1984. Mesozoic Source rocks on Svalbard. In: SPENCER, A. M. (ed.) Petroleum Geology of the North European Margin. Graham & Trotman, London, 371-382. & DUNCAN, R. A. 1993. Late Pliocene basaltic volcanism on the Western Barents Shelf margin: implications from petrology and 40Ar-39Ar dating of volcaniclastic debris from a shallow drill core. Norsk Geologisk Tidsskrift, 73, 209-225. -& FANAVOLL, S. 1987. The shelf near Bjornoya. In: MORK, A. (ed.) Geological Excursion Guide to Bjornoya , IKU, Trondheim. & WORSeEY, D. 1979. The Triassic and Lower Jurassic succession of Svalbard: a review. In: Norwegian Sea Symposium (NSS/29). NPF, Stavanger, 1-22. , EMBRV, A. F. & WEI,rSCHA,r,W. 1989. Triassic transgressive-regressive cycles in the Sverdrup Basin, Svalbard and the Barents Shelf. In: COLL~NSON,J. D. (ed.) Correlation in Hydrocarbon Exploration. London, Graham & Trotman, 113-130. , KNARUD, R. & WORSLEY, D. 1982. Depositional and diagenetic environments of the Triassic and Lower Jurassic succession of Svalbard. In: EMBRY, A. R. & BALKWILL,H. R. (eds) Arctic Geology and Geophysics. Memoirs of the Canadian Society of Petroleum Geologists, 8, 371-398. , VmRAN, J. O. & HOCHUL~, P. 1990. Geology and palynology of the Triassic succession of Bjornoya. Polar Research, 8, 141 164. -- - , KORCHINSKAYA,M. V., PCHELINA,T. M., FEFILOVA,L. A., VAVlLOV,M. N. 8r WHTSCnA,r, W. 1992. Triassic rocks in Svalbard, the Arctic Soviet islands and the Barents Shelf: beating on their correlations. In: VORREN, T. O. et aL (eds) Arctic Geology and Petroleum Potential. NPF Special Publication, 2, Elsevier, Amsterdam, 457-479. MORRIS, A. 1982. Low grade (greenschist facies) metamorphism in southern Prins Karls Forland, Svalbard. Polar Research, 2, 17-56. - - 1 9 8 8 . Polyphase deformation in Oscar II Land, central western Svalbard. Polar Research, 6, 69-84. - - 1 9 8 9 . Distributed right-lateral strike-slip in Prins Karls Forland, western Svalbard. Polar Research, 7, 79-82. MORRIS, A. P. 1981. Competing deformation mechanisms and slaty cleavage in deformed, quartzose meta-sediments. Journal of the Geological Society, London, 455-462. MORRIS, N. J. & FORTEV, R. A. 1976. The significance of Tironucula gen. nov. to the study of bivalve evolution. Journal of Paleontology, 50, 701 709. MoY-THOMAS, J. & MILES, R. S. 1971. Palaeozoic Fishes. Chapman & Hall, London. MUIR-WOOD, H. M. & COOPER, G. A. 1960. Morphology, classification andlife habits of the Productoidea (Braehipoda). Memoirs of the Geological Society of America, 81. MOLLER, R. D. & SPIELHAOEN,R. F. 1990. Evolution of the Central Tertiary Basin of Spitsbergen: towards a synthesis of sediment and plate tectonic history. Palaeogeography, Palaeoclimatology, Palaeoecology, 80, 153-172. MtJRASHOV, L. G. 1976. [New data on the stratigraphy of the Devonian deposits of the northern coast of Hornsund, Spitsbergen]. In: SOKOLOV,V. N. (ed.) Geology of Svalbard. A Collection of Articles. NIIGA, Leningrad, 92-102. - - 1 9 9 6 a . Lower-Middle Devonian stratigraphy of northern Andrre Land. In: KRASII.'SHCmKOV,A. A. (ed.) Soviet Geological Research in Svalbard 1962-1992. Norsk Polarinstitutt Meddelelser, 139, 34. - - 1 9 9 6 b . Devonian deposits in the Mimerdalen area, Dickson Land, and the Hornsund area, Torell Land. In: KRASTL'SHCHmOV,A. A. (ed.) Soviet Geological Research in Svalbard 1962-1992. Norsk Polarinstitutt Meddelelser, 139, 40. - - 1 9 9 6 c . Stratigraphy and composition of Devonian deposits on Spitsbergen (in type sections). In: Ka_~SXIJSHCHIKOV,A. A. (ed.) Soviet Geological Research in Svalbard 1962-1992. Norsk Polarinstitutt Meddelelser, 139, 43. & KAPa~TAJU,rE-TALIMAa, V. N. 1980. [New data on the stratigraphy of Fraenkelryggen and the Ben Nevis suite of the lower Devonian of Spitsbergen]. In: SEMEVSKW, D. V. (ed.) Geologiya osadochnogo chekla arkhipelaga Sval'bard. Sbornik nauchnykh trudov [Geology of the Sedimentary Mantle of the Svalbard Archipelago. A Collection of Scientific Papers]. NIIGA, Leningrad, 5-12. & MOVdN, Yu. I. 1976. [Stratigraphic separation of the Devonian deposits of the Spitsbergen region]. In: SOKOLOV,V. N. (ed.) Geology of Svalbard. A Collection of Articles. NIIGA, Leningrad, 78-91. -

-

-

-

-

&

-

1 3 8 ,

-

-

501

& - - 1 9 7 9 . Stratigraphic subdivision of the Devonian deposits of Spitsbergen. Norsk Polarinstitutt Skrifter, 167, 249-261. - - , PCHELINA,T. M. & SEMEVSKIY,D. V. 1983. [New data on evidence of volcanism in the Lower Devonian and Upper Triassic formations of Vestspitsbergen]. In: KRASle'SHCHIKOV,A. A. & BASOV, V. A. (eds) Geologiya Shpitsbergena: spornik nauchnykh trudov [The Geology of Spitsbergen: a Collection of Papers]. PGO "Sevmorgeo", Leningrad, 96-101. MYHRE, A. M. 1984. Compilation of seismic velocity measurements along the margins of the Norwegian-Greenland Sea. Norsk Polarinstitutt Skrifter, 180, 41-61. & ELDHOLM, O. 1988. The western Svalbard margin (74~176 Marine and Petroleum Geology, 5, 134-156. -& THIEDE, J. 1995. North Atlantic-Arctic gateways. In: Proceedings of the Ocean Drilling Program. Initial Reports, A151, 5-26. --, EeDHOLM, O. & SUNDVOR, E. 1982. The margin between Senja and Spitsbergen zones: implications from plate tectonics. Tectonophysics, 89, 33-50. - - , THIEDE, J. & FIR,rH, J. 1994. North Atlantic Arctic gateways. Joides Journal, 14 (February 1994). MYRVANG, A. M. & UTSl, J. 1989. Rock mechanics investigations in the Svea coal mine, Svalbard. In: BANDOPADHYAY,S. & SKUDRZYK, F. J. (eds) Mining in the Arctic. Proceedings of the 1st International Symposium on Mining in the Arctic, Fairbanks, 1%19 July 1989. Balkema, Rotterdam, 241-244. NACY, J. 1963. Echinoderms from the Lower Cretaceous of Vestspitsbergen. Norsk Polarinstitutt Arbok 1962, 192-193. - - 1 9 6 5 . Oil exploration in Spitsbergen. Polar Record, 12, 703-708. - - 1 9 6 6 . Preliminary report on the Geology of eastern Torell Land, Vestspitsbergen. Norsk Polarinstitutt Arbok 1964, 69-72. - - 1 9 6 8 . Oil exploration in Spitsbergen 1967. Polar Record, 14, 197. - - 1 9 7 0 . Ammonite faunas and stratigraphy of Lower Cretaceous (Albion) rocks in southern Spitsbergen. Norsk Polarinstitutt Skrifter, 152, 1-58. - - 1 9 7 3 . [Fossil bearing rock fragments" of Mesozoic age J~om the Svalbardbank]. N T N F Continental Shelf Project, Publication 42. & LOFALDLI,M. 1981. Agglutinating foraminifera in Jurassic dark shale facies in Svalbard. In: NEALE, J. W. & BRASIER,M. D. (eds) Mierofossilsfrom Recent and Fossil Shelf Seas. Ellis Horwood, Chichester, 114-121. , LOFALDLI,M. & BXCKSTRON, S. A. 1988. Aspects of foraminiferal distribution and depositional conditions in Middle Jurassic to Early Cretaceous shales in eastern Spitsbergen. In: ROGL, F. & GRADSrEIN, F. M. (eds) Proceedings of the Second Workshop on Agglutinated Foraminifera, Vienna 1986. Abhandlungen der Geologischen Bundesanstalt, 41, 28"/300. , , & JOI~ANSEY, H. 1990. Agglutinated foraminiferal stratigraphy of Middle Jurassic to basal Cretaceous shales, central Spitsbergen. In: HEMeEBEN,C., KaMINSKh M. A., KUHNT, W. & SCOTT,D. B. (eds) Paleoecology, Biostratigraphy, Paleoceanography and Taxonomy of Agglutinated Foraminifera. Kluwer, Dordrecht, 969-1015. NAKAMURA, K. 1992. Investigation on the Upper Carboniferous-Upper Permian succession of West Spitsbergen 1989 1991. Hokkaido University, Sapporo. , KIMURA, G., OHTA, Y. & LAURI,rZEN, O. 1990. Report on The Cooperative Geological Study between Norsk Polarinstitutt and Hokkaido University, Japan, in Svalbard 1984. In: TATSUMI, T. (ed.) The Japanese Scientific Expeditions to Svalbard 1983-1988. Kyoikusha, Tokyo, 125 134. --, -& WINSNES,T. S. 1987. Brachiopod zonation and age of the Permian Kapp Starostin Formation (central Spitsbergen). Polar Research, 5, 207-219. ---, --, -& LAURI,rZEN, O. 1990. Permian and Permian-Triassic boundary in Central Spitsbergen. In: TATSUMh T. (ed.) The Japanese Scientific Expeditions to Svalbard 1983-1988. Kyoikusha, Tokyo, 135-154. , TAZAWA, J. & KUMON, F. 1992. Permian brachiopods on the Kapp Starostin Formation, West Spitsbergen. In: NAKAiVIURA,K. (ed.) Investigations on the Upper Carboniferous-Upper Permian succession of West Spitsbergen 1989-1991. Hokkaido University, Sapporo, 7~96. NAKAZAWA, K., NAKAMURA, K. & KIMURA, G. 1987. Discovery of Otoceras boreale Spath from West Spitsbergen. Proceedings of the Japan Academy, 63B, 171-174. ,SuzuKt, H., KUMON, F. & WINSNES, T. S. 1990. Scientific results of the Japanese Geological Expedition to Svalbard 1986. In: TATSUMI, T. (ed.) The Japanese Scientific Expeditions to Svalbard 1983-1988. Kyoikusha, Tokyo, 179-214 NAKREM, H. A. 1988. Permian bryozoans from southern Spitsbergen and Bjornoya. A review of bryozoans described by J. Malecki (1968, 1977). Polar Research, 6, 113-121. - - 1 9 9 1 . Conodonts from the Permian succession of Bjornoya (Svalbard). Norsk Geologisk Tidsskrift, 71, 235-248. - - - 1 9 9 4 . Bryozoans from the Lower Permian Voringen Member (Kapp Starostin Formation), Spitsbergen, Svalbard. Norsk Plarinstitutt Skrifter, 196, 1-60. & MORK, A. 1991. New early Triassic bryozoa (Trepostomata) from Spitsbergen, with some remarks on the stratigraphy of the investigated horizons. Geological Magazine, 128, 129-140. & SPJZLDN~S, N. 1995. Ramipora hochstetteri Toula, 1875 (Bryozoa, Cystoporata), from the Permian of Svalbard. Journal of Paleontology, 69, 831-838. - - , NILSSON,I. & MANGERUD, G. 1992. Permian biostratigraphy of Svalbard (Arctic Norway) - a review. International Geology Review, 34, 933-959. NANSEN, F. 1920. [An expedition to Spitsbergen], Kristiania. NAREBSrd, W. 1960. Petrochemical characteristics of amphibolite rocks of the Lower Skfilfjellet Series, Hecla Hock Succession, Wedel Jarlsberg Land. Bulletin de l'Acad~mie Polonaise des Sciences. Sdrie des Sciences Gdologiques et G~ographiques, 8, 173-179. - - 1 9 6 0 . Calculation of the mineral composition of rocks of the albite-epidoteamphibolite facies. Bulletin de l'Acadimie Polonaise des Sciences. Sdrie des Sciences G~ologiques et Gdographiques, 8, 165-171. -

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502

REFERENCES

NATHORST, A. G. 1884. [Record of the geological expedition to Spitsbergen made together with G. De Geer in the year 1882]. Bib. Kungliga Svenska Vetenskapsakademiens Handlinger, 9, 1-78. Uppsala & Stockholm. --1892. [Preliminary note on plant fossils gathered in Spitsbergen by G. Nordenskiold]. Bih. Kungliga Svenska Vetenskapsakademiens Handlinger, 17, 61-66. Uppsala & Stockholm. --1894. Zur pal/iozoischen Flora der arktischen Zone enthaltend die auf Spitzbergen, auf der B/iren-Insel und auf Novaja Zemlja von den schwedischen Expeditionen entdeckten palhozoischen Pflanzen. Kungliga Svenska Vetenskapsakademiens Handlingar, 26, 1-80. Stockholm. - - 1 8 9 4 . [On the Palaeozoic flora of the Arctic zone]..lb. Geol. ReichsAnst. 44, 87-98. - - 1 8 9 6 . Marine Conchylien im Terti~ir Spitzbergens und Ost-Gr6nlands. Zeitschrift der Deutschen Geologischen Gesellschaft, 48, 983-986. 1897a. zur Mesozoischen Flora Spitzbergens gegriindet auf die sammlungen der Schwedischen Expeditionen. Kungliga Svenska Vetenskapsakademiens Handlingar, 30, 1-77. Stockholm. - - 1 8 9 7 b . Nachtr/igliche Bemerkungen fiber die mesozoische Flora Spitzbergens. Kungliga Svenska Vetenskapsakademiens Arsbok, 54, 383-387. - - 1 8 9 9 . Fossil plants from Franz Josef Land. Norwegian Polar Expedition 18931896, Scientific Results, 1, 1-22. - - 1 8 9 9 . [Explanatory remarks on the new map of Beeren Eiland]. Ymer, 19, 171-185. - - 1 9 0 0 . Uber die oberdevonische Flora (die "Ursaflora") der B/iren Insel. Bulletin of the Geological Institution of the University of Uppsala, 4, 152-156. - - 1 9 0 0 . Fossil Plants from Josef Land, Norwegian Polar Expedition 1893-1896. Science Research, 1. - - 1 9 0 1 . Bidrag til Kung Kads Land geologi. Geologiska Fdreningens Stockholm Fdrhandlingar, 23, 341 378. - - 1 9 0 2 . Zur oberdevonischen Flora der B/iren-Insel. Kungliga Svenska Vetenskapsakademiens Handlingar, 36, 1-60. Stockholm. - - 1 9 1 0 a . Beitrage zur Geologie der B~iren Insel, Spitzbergens und des K/Snig-KarlLandes. Bulletin of the Geological Institution of the University of Uppsala, 10, 261-416. - - 1 9 1 0 b . Line vorl~iufige Mitteilung von Prof. J. F. Pompeckj fiber die Altersfrage der Juraablagerungen Spitzbergens. Geologiska Fdreningens Stockholm Fdrhandlingar, 32, 1-9. - - 1 9 1 1 . On the value of fossil floras of the arctic regions as evidence of geological climates. Geological Magazine, 5, 217-225. - - 1 9 1 3 . Die pflanzenffihrenden Horizonte innerhalb der Grenzschichten des Jura und der Kreide Spitzbergens. Geologiska Fdreningens Stockholm Ffrhandlingar, 35, 273-282. - - 1 9 1 4 . Nachtr~ige zur pal~iozoischen Flora Spitzbergens. In: NATHORST,A. G. (ed.) Zur fossilen Flora der Polarldnder, 1. Stockholm, 1-110. - - 1 9 1 9 a . Zwei kleine pal~iobotanische Notizen. 1. Arctodendron kidstonii (Nath.) nov. conb. 2. Line weitre Fundst/itte eines terti'/iren Ginkgo auf Spitzbergen. Geologiska Fdreningens Stockholm Fdrhandlingar, 41, 457 459. - - 1 9 1 9 b . Ginkgo adiantoides (Unger) Heer im Terti~ir Spitzbergens nebst einer kurzen Ubersicht der iibrigen fossilen Ginkgophyten desselben Landes. Geologiska FfJreningens Stockholm Fdrhandlingar, 41,233-248. - - 1 9 2 0 . Zur Kulmflora Spitzbergens. In: NATHORST,A. G. (ed.) Zurfossilen Flora der Polarldnder, II. Stockholm, 1-45. 1920. Einige Psygmophyllum-B1/itter aus dem Devon Spitzbergens. Bulletin of the Geological Institution of the University of Uppsala, 18, 1-8. - - 1 9 2 0 . Zur fossilien Flora der Polarldnder. Zur Kulmfora Spitzbergens, 3. NEIZVESTNOV,Y. V. & SEMEVSKIY,D. V. (eds) 1983. [The Hydrogeology, Engineering Geology and Geomorphology of the Spitsbergen Archipelago]. PGO "Sevmorgeo", Leningrad. NEMEC, W., STEEL, R. J., GJELBERG,J., COLLINSON,J. D., PRESTHOLM,E. & OXNEVAD, I. E. 1988a. Anatomy of collapsed and re-established delta front in Lower Cretaceous of eastern Spitsbergen: gravitational sliding and sedimentation processes. American Association of Petroleum Geologists Bulletin, 72, 454 476. . . . . & WORSLEY, O. 1988b. Exhumed rotational slides and scar infill features in a Cretaceous delta front, eastern Spitsbergen. Polar Research, 6, 105-112. NEWTON, E. T. & TEALL, J. J. H. 1897. Notes on a Collection of Rocks and Fossils from Frans Josef Land, made by Jackson-Harmsworth Expedition during 1894 1896. Quarterly Journal of the Geological Society of London, 53, 472519. - & 1898. Additional Notes on Rocks and Fossils from Franz Josef Land. Quarterly Journal of the Geological Society of London, 54, 646 651. NIELSEN, A. T. 1992. Intercontinental correlation of the Arenigian (Early Ordovician) based on sequence and ecostratigraphy. In: WEARY, B. D. & LAURIE, J. R. (eds) Global Perspectives on Ordovician Geology. Balkema, Rotterdam, 367-372. NIEWlADOMSKI,J. 1982. Report on the activities of the research expedition of the Polish Academy of Sciences to Spitsbergen 1980/1981. Polish Polar Research, 3, 123-127. NIKIFOROVA, A. I. 1936. [Some Early Permian bryozoans from Novaya Zemlya and Spitsbergen]. Trudy Arkticheskogo Nauchno-Issledovatel'skogo Instituta, 58, 113-141 [in Russian with English summary]. NILSSON, T. 1941. The Downtonian and Devonian vertebrates of Spitsbergen. VII. Order Antiarchi. Skrifter om Svalbard og lshavet, 82, 1-54. - - 1 9 4 2 . Sassenisaurus, a new genus of Eotriassic Stegocephalians from Spitsbergen. Bulletin of the Geological Institution of the University of Uppsala, 30, 91-102. --1943. (Jber einige postkraniale Skelettreste der triassischen Stegocephalen Spitzbergens. Bulletin of the Geological Institution of the University of Uppsala, 30, 227-272. - - 1 9 4 3 . On the morphology of the lowerjaw of Stegocephalia with special reference to Eotriassic Stegocephaliansfrom Spitsbergen. L Descriptivepart. Kungliga Svenska Vetenskapsakademiens Handlingar, 20, Stockholm.

On the morphology of the lowerjaw of Stegocephalia with special reference to Eotriassic Stegocephalians from Spitsbergen. II. General part. Kungliga Svenska Vetenskapsakademiens Handlingar, 21, Stockholm. - - 1 9 4 6 . On the genus Peltostega Wiman and the classification of the Triassic Stegocephalians. Kungliga Svenska Vetenskapsakademiens Handlinger, 23, 1-55. Uppsala & Stockholm. NIOCAILL, C. M., VAN DER PLUIJM & VAN DER VOO, R. 1997. Ordovician paleogeography and the evolution of the Iapetus Ocean. Geology, 25, 159-162. NISSAN, K. 1941. [Voyage of la Recherche]. Norsk Geografiske Tiddsskrift, 8, 161-218. NIXON, W. A., DOWDESWELL,J. A., COOPER, A. P. R., DREWRY, D. J., WATTS, L. G., LIESTOL, O. & SMITH, R. A. 1985. Applications and limitations of finite element modeling to glaciers: a case study. Journal of Geophysical Research, 90, I1303-11 311. NOLDEKE, W. 1962. zur Geologie Westspitzbergen. Zeitschrift fli'r Angewandte Geologie, 8, 96-100. NORDENSKI()LD, A. E. 1863. [Geographic and geognostic description of the northeast part of Spitsbergen and Hinlopen Strait]. Kungtiga Svenska Vetenskapsakademiens Handlingar, 4. Stockholm. - - 1 8 6 6 . Utkast till Spetsbergens geologi ]Sketch of the geology of Spitzbergen]. Kungliga Svenska Vetenskapsakademiens Handlingar, 6 [English translation published 1867, Norstedt, Stockholm]. - - 1 8 6 7 . Sketch of the geology of Spitsbergen. Kungliga Svenska Vetenskapsakademiens Handlinger, 6. Norstedt, Stockholm [Translated from Transactions of Royal Swedish Academy of Sciences 1866]. - - 1 8 7 0 . Mittheilung fiber die tertifiren und postterti/iren Lager Spitzbergens. In: HEER, O. (ed.) Die miocene Flora unf Fauna Spitzbergens. Kungliga Svenska Vetenskapsakademiens Handlingar, 8. Stockholm, 18-25. - - 1 8 7 1 . Die Bergkalkformation auf der Bdren-Insel und Spitzbergen. Kungliga Svenska Vetenskapsakademiens Handlingar, 9. Stockholm, 25-31. - - 1 8 7 5 . [Record of the Swedish Polar Expedition, 1872-1873: lists of minerals found in Spitsbergen and Bear Island]. Kungliga Svenska Vetenskapsakademiens Handlinger, B2. Uppsala & Stockholm, 21-28. - - 1 8 7 5 . [A sketch of the geology of Isfjorden and Bellsund]. Utkast till Isfjordens och Bellsounds geologi. Geologiska Fdreningens Stockholm Fdrhandlingar, 2, 243-260 and 301-322 and 356-373 [translation in Geological Magazine, 1876. - - 1 8 7 6 . Sketch of the geology of Ice Sound and Bell Sound. Geological Magazine, 13, (2) 63-75; (3) 16-33; (3) 118-127; (4) 255-267; (10) 393-401. NORDENSKIOLD,G. 1892. Redogdrelsefffr den svenska expeditionen till Spetsbergen 1890 [Record of the Swedish Expedition to Spitsbergen in 1890]. Kungliga Svenska Vetenskapsakademiens Handlingar, 17. Stockholm. NORDENSKJOLD, O. 1921. Die nordatlantischen Polarinseln. Handb. Regionalen Geol., 4 , 1-30. -& MECKING, L. 1928. The geography of the Polar regions. Special Publication of the American Geographical Society, 7, 138-158. NORTHERN EXPLORATIONCOMPANY 1913. Marble Island (unpublished confidential report). Northern Exploration Company Ltd, London. NOTTVEDT, A. 1985. Askelodden delta sequence (Palaeocene) on Spitsbergensedimentation and controls on delta formation. Polar Research, 3, 22-48. NorrVEDT, A., BERGLUND,L. T., RASSMUSSEN,E. & STEEL, R. J. 1988. Some aspects of Tertiary tectonics and sedimentation along the western Barents Shelf. In: MORTON, A. C. & PARSON, L. M. (eds) Early Tertiary Volcanism and the Opening of the NE Atlantic. Geological Society, London, Special Publication, 39, 421-425. , CECCHI, M., GJELBERG, J. G., KOSTENSEN, S. E., LONOY, A., RASMUSSEN, A., RASMUSSEN, E., SKOTr, P. H. & VAN VEEN, P. M. 1993. Svalbard Barents Sea correlation: a short review. In: VORREN, P. M. et al. (eds) Arctic Geology and Petroleum Potential. Norwegian Petroleum Society, Special Publication, 2, Elsevier, Amsterdam, 363-375. , GABRIELSEN, R., HAUGSBO, H., KLOVJAN,O., MIDBOE, P. S., RASMUSSEN, E. & SKOTT, P. H. 1992. Stratigraphy and sedimentology of the Forlandsundet Graben (abstract). Norsk Geologisk Tidsskrift, 72, 137. , LIVBJERG,F. & MIDBOE, P. S. 1988. Tertiary deformation on Svalbard various models and recent advances. In: DALLMANN, W. K., OHTA, Y. & ANDRESEN, A. (eds) Tertiary Tectonics of Svalbard. Norsk Polarinstitutt, Report Series, 46, 79-84. , , & RASMUSSEN, E. 1992. Hydrocarbon potential of the Central Spitsbergen Basin. ln: VORREN, T. O. et al. (eds) Arctic Geology and Petroleum Potential. Norwegian Petroleum Society, Special Publication, 2, Elsevier, Amsterdam, 333 361. NOWlNSKI, A. 1982. Some new species of Tabulata from the Lower Permian of Hornsund, Spitsbergen. In: BIERNAT,G. & SZYMANSKA,W. (eds) Palaeontological Spitsbergen Studies'. Palaeontologica Polonica, 43, 83-96. - - 1 9 9 1 . Late Carboniferous to Early Permian Tabulata from Spitsbergen. Palaeontologia Polonica, 51, Wydawnictwo Naukowe PWN, Warsaw. NUNNS, A. G. 1982. The structure and evolution of the Jan Mayen ridge and surrounding areas. American Association of Petroleum Geologists, Memoir, 34, 193-208. 1983. Plate tectonic evolution of the Greenland-Scotland ridge and surrounding regions. In: BOTT, M. H. P. et al. (eds) Structure and development of the Greenland Scotland ridge, new methods and concepts. Plenum, New York, 11 30. NUTTALL,A.-M., HAGEN,J. O. & DOWDESWELL,J. A. 1997. Quiescent-phase changes in velocity and geometry of Finsterwalderbreen, a surge-type glacier in Svalbard. Annals of Glaciology, 24, 249-254. NYLAND, l . , JENSEN, L. N., SKAGEN, J., SKARPNES, O. • VORREN, T. 1992. Tertiary uplift and erosion in the Barents Sea: magnitude, timing and consequences. In: LARSEN, R. M., BREKKE, H., LARSEN, B. T. & TALLERAAS,E. (eds) Structural and Tectonic Modelling and its Application to Petroleum Geology. Norwegian Petroleum Society (NPF), Special Publication, 1, Elsevier, Amsterdam, 153-162. --1944.

REFERENCES NYSAETHER,E. 1977. Investigations on the Carboniferous and Permian stratigraphy of the Torell Land area, Spitsbergen. Norsk Polarinstitutt flrbok 1976, 21-41. & SAEBOEE, A. 1976. Geology and Petroleum possibilities of the Svalbard Archipelago. In: Offshore North Sea Technology Conference and Exhibition: Exploration, Geology and Geophysics Section. North Sea Technology Conference, Stavanger, 1-23. NYSTAD, A. N. 1996. [Geology and petroleum resources in the Barents Sea]. Oljedirektoratet, Stavanger. NYSTUEN, J. P. 1976. Facies and sedimentation of the Late Precambrian Moelv tillite in the eastern part of the Sparagmite Region, southern Norway. Norges Geologiske Undersokelse, Bulletin, 67, 1-70. 1982. Late Proterozoic basin evolution on the Baltoscandian Craton: the Hedmark Group, southern Norway. Norges Geologiske Undersokelse, 3ulletin, 67, 1-74. - - 1 9 8 5 . The Varanger Ice Age in the North Atlantic. Palaeogeography, Palaeoclimatology, Palaeoecology, 51, 209-229. - - - (ed.) 1989. Rules and recommendations for naming geological units by the Norwegian Committee on Stratigraphy. Norsk Geologisk Tidsskrift, 69, Supplement 2, 1-111. OBERG, P. 1877. Om trias-ffrsteningar frdn Spetsbergen. Kungliga Svenska Vetenskapsakademiens Handlingar, 14. Stockholm. OBRUCHEV, S. 1927. [Geological sketch of the east coast of Spitsbergen between Kvalv~gen and Agardhbukta]. Bericht des Wissenschaftlichen Meeresinstituts, 2, 59-88 [Russian with German summary]. ODEGARD, R . S., HAMRAN, S.-E., BO, P. H., ETZELMOLLER,B., VATNE, G. & SOLLID, J. L. 1992. Thermal regime of a valley glacier, Erikbreen, northern Spitsbergen. Polar Research, 11, 69-79. , SOLLID, J. L. & TROLLVIK, J. A. 1987. Forlandsundet. Scale 1:200000. Norsk Polarinstitutt (1 sheet). ODELBERG, H. 1916. [Sweden's coal resources on Spitsbergen]. Sten oeh Cement. Svensk Tidskr. Prakt. Geol..4rg, 13, 1-3. ODELL, N. E. 1922. Geological notes from the Oxford Expedition to Spitsbergen. Geographical Journal, 60, 424-426. - - 1 9 2 7 . Preliminary notes on the geology of the eastern parts of central Spitsbergen: with special reference to the problem of the Hecla Hook Formation. Quarterly Journal of the Geological Society of London, 83, 147-162. OERLEMANS, J. 1992. Climate sensitivity of glaciers in southern Norway: applications of an energy-balance model to Nigardsbreen, Hellstugubreen and Alfotbreen. Journal of Glaciology, 38, 223-232. - - 1 9 9 3 . Modelling of glacier mass balance. In: PELT~ER, W. R. (ed.) Ice in the Climate System. Springer-Verlag, Berlin, 101-116. OFFRET, A. 1911. Le XI e congr6s g6ologique international en Su6de. Revue G~nerale des Sciences pures et Appliquees, 22, 359-373. OHLSON, B. 1979. [Coal mines, marble quarries and fossil finds in Svalbard]. Nordenski(ild-Samfundets Tidsskrift, 39, 24-35. OHTA, Y. 1969. The geology and structure of metamorphic rocks in the Smeerenburgfjorden area, north-west Vestspitsbergen. Norsk Polarinstitutt .4rbok 1967, 52-72. - - 1 9 7 8 a . Caledonian metamorphism in Svalbard, with some remarks on the basement. Polarforschung, 48, 78-91. - - 1 9 7 8 b . Caledonian basic rocks of Storoya and Kvitoya, NE Svalbard. Norsk Polarinstitutt flrbok 1977, 25-42. - - - 1 9 7 9 . Blue schists from Motalafjella, western Spitsbergen. Norsk Polarinstitutt Skrifter, 167, 171-217. - - 1 9 8 1 . Caledonian fractures on Svalbard. In: GABRIELSEN,R. H., RAMBERG,1. B., ROBERTS, D. 8z STEINLEIN, O. (eds) Proceedings of the Fourth International Conference on Basement Tectonics. International Basement Tectonics Association, Oslo, Norway, Publications, 4, 339-350. - - 1 9 8 2 a . Morpho-tectonic studies around Svalbard and the northern-most Atlantic. In: EMBRY, A. R. & BALKWlLL, H. R. (eds) Arctic Geology and Geophysics. Memoirs of the Canadian Society of Petroleum Geologists, 8, 415-429. - - 1 9 8 2 b . Hecla Hoek rocks in central and western Nordaustlandet. Norsk Polarinstitutt Skrifter, 178, 1-60. - - 1 9 8 5 . Geochemistry of the late Proterozoic Kapp Hansteen igneous rocks of Nordaustlandet, Svalbard. Polar Research, 3, 69-92. - - 1 9 8 5 . Geochemistry of Precambrian basic igneous rocks between St. Jonsfjorden and Isfjorden, central western Spitsbergen. Polar Research, 3, 49-67. - - 1 9 8 7 . Ordovician-Silurian restoration between Svalbard and Ellesmere Island (abstract). Norsk Geologisk Tidsskrift, 67, 436. - - 1 9 8 8 . Basement of W-Spitsbergen: an outline. In: DALLMANN,W. K., OHTA, Y. t~ ANDRESEN, A. (eds) Tertiary Tectonics of Svalbard. Norsk Polarinstitutt, Report Series, 46, 9-12. - - 1 9 8 8 . Structure of the Carboniferous strata at Trygghamna and along the SE margin of the Forlandsundet Graben. In: DALLMANN, W. K., OHTA, Y. & ANDRESEN, A. (eds) Tertiary Tectonics of Svalbard. Norsk Polarinstitutt, Report Series, 46, 25-28. - - 1 9 8 8 . An additional presentation on the basement-platform boundary structures in NW Nordenski61d Land. In: DALLMANN, W. K., OHTA, Y. & ANDRESEN, A. (eds) Tertiary Tectonics of Svalbard. Norsk Polarinstitutt, Report Series, 46, 3~34. - - 1 9 9 2 . Recent understanding of the Svalbard basement in the light of new radiometric age determinations. In: DALLMANN,W. K., ANDRESEN, A. & KRILL, A. (eds) Post-Caledonian Tectonic Evolution of Svalbard. Norsk Geologisk Tidsskrift, 72, 1-6. - - 1 9 9 4 . Caledonian and Precambrian history in Svalbard: a review and an implication of escape tectonics. Tectonophysics, 231, 183-194. -& DALLMANN, W. K. 1992. Geological Map of Svalbard. 1:100,000, sheet BI2G. Torellbreen (preliminary edition, updated 1996). Norsk Polarinstitutt, Oslo.

503

, BERNARD-GRIFFITHS,J. & PEUCAT, J. J. 1992, 1996. Geochronological studies on the basement rocks of Svalbard. In: Arctic Research Seminar Proceedings. October 15-16, 1992. , DALLMEYER, R. D. & PEUCAT, J. J. 1989. Caledonian terranes in Svalbard. In: DALLMEYER, R. D. (ed.) Circum-Atlantic Paleozoic Orogens, Special Papers of the Geological Society of America, 230, 1-15. --, GJELSVIK, Z. • MCCANN, A. 1995. Hornbaekpollen Thrust Zone in Liefdefjorden, NW Spitsbergen. In: Abstract. Geonytt, 95(1), 55. --, HIRAJIMA, T. & HIROI, Y. 1986. Caledonian high-pressure metamorphism in central western Spitsbergen. In: EVANS, B. W. &; BROWN, E. H. (eds) Blueschists and Eclogites. Memoirs of the Geological Society of America, 164, 205 216. --, HIROI, Y. & HIRAJIMA, T. 1983. Additional evidence of pre-Silurian highpressure metamorphic rocks in Spitsbergen. Polar Research, 1, 215-218. - - , HJELLE, A., ANDRESEN, A., DALLMANN,W. K. & S.~LVIGSEN,O. 1991. Geological Map of Svalbard. I:100,000. Sheet BgG Isfjorden, with description. Norsk Polarinstitutt Temakart, No. 16. --_--, & DALLMAN, W. K. 1996. Geological Map of Svalbard 1:100000, Sheet A4G, Vasahalvoya. Norsk Polarinstitutt, Preliminary edition. --, --, LEPVRIER, C. t~ TEBEN'KOV, A. M. 1995. Northern continuation of Caledonian high-pressure metamorphic rocks in central-western Spitsbergen. Polar Research, 14, 303-315. OKAY, N. 1994. Evidence for propagating asthenosphere corridors: along the transtensional volcanic margins of the Norwegian-Greenland Sea. EOS (Transactions of the American Geophysical Union), 75, 321. --1995. Magmatism and rift margin evolution: evidence from the northern Norwegian Greenland Sea. Terra Abstracts, 7, 151. OLJEDIREKTORATET 1996. [Geology and petroleum resources in the Barents Sea]. Oljedrektor, Stravanger. OLSEN, E. L. 1920. [The coal deposits in Spitsbergen]. Nat. Verd. Kjob. Aarg., 4, 252-309. OLSSON, I. & BLAKE, W. J. 1962. Problems of radiocarbon dating of raised beaches, based on experience in Spitsbergen. Norsk Geologisk Tidsskrift, 18, 47-64. OLSSON, J. U. 1968. Radiocarbon analysis of lake sediment samples from Bjornoya 1968. Geografiske Annaler, AS0. OOSTERVOLD,P. 1970. Geology-Palaeontology. De Nederlandse Spitsbergen Expeditie 1968-1969, Preliminary Report Series, 4. ORBELL 1973. Palynology of the British Rhaeto-Liassic. Bulletin of Geological Survey of Great Britian, 44, 1-44. ORHEIM, A. 1979. Coal Mining in Spitsbergen. POAC 79: Port and Ocean Engineering under Arctic Conditions, Norwegian Institute of Technology. - - 1 9 8 2 . Undiscovered Tertiary coal resources of Svalbard: an assessment, using the Monte Carlo simulation. In: EMBRY, A. F. t~z BALKWlLL, H. R. (eds) Arctic Geology and Geophysics. Memoirs of the Canadian Society of Petroleum Geologists, 8, 399-413. , ARONSEN, H. A., JENSEN, L. N., SKARPNES, O. & LARSEN, B. T. 1988. Seismic mapping of Grimfjellet and Isfjorden, Svalbard: tectonic implications. In: DALLMANN, W. K., OHTA, Y. & ANDRESEN, A. (eds) Tertiary Tectonics of Svalbard. Norsk Polarinstitutt, Report Series, 46, 63-66. ORVI~, T. 1957. Notes on some Paleozoic lower vertebrates from Spitsbergen and North America. Norsk Geologisk Tidsskrift, 37, 285-353. - - 1 9 6 9 . The vertebrate fauna of the Primaeva Beds of the Frankelryggen Formation of Vestspitsbergen and its biostratigraphic significance. Lethaia, 2, 219-239. - - 1 9 6 9 . A new brachythoracid arthrodire from the Devonian of Dickson Land, Vestspitsbergen. Lethaia, 2, 261-271. - - 1 9 6 9 . Vertebrates from the Wood Bay Group and the position of the EmsianEifelian boundary in the Devonian of Vestspitsbergen. Lethaia, 2, 273-328. - - 1 9 6 9 . Thelodont scales from the Grey Hoek Formation of Andr6e Land, Spitsbergen. Norsk Geologisk Tidsskrift, 49, 387-401. - - 1 9 7 1 . Comments on the lateral lens system of some Brachythoracid and Ptyctodontid Arthrodires. Zool. Scr., 1, 5-35. ORVIY, A. K. 1934. Geology of the Kings Bay region, Spitsbergen. Skrifter om Svalbard og Ishavet, 57, 1 195. - - 1 9 4 0 . Outline of the geological history of Spitsbergen. Skrifter om Svalbard og Ishavet, 78, 1-57. - - (ed.) 1942. The place-names of Svalbard. Skrifter om Svalbard og Ishavet, 80,1-539 - - 1 9 4 7 . Bibliography of literature about the geology, physical geography, useful minerals, and mining of Svalbard. Skrifter om Svalbard og Ishavet, 89, 1-12. - - 1 9 5 8 . Supplement 1 to the Place Names of Svalbard dealing with new names 1935-55. Norsk Polarinstitutt Skrifter, 112, 1-131. OSMOLSKA, H. 1968. Two new trilobites from the Treskelodden beds of Hornsund (Vestspitsbergen). Acta Palaeontologica Polonica, 13, 605-617. Orro, S. C. & BAILEY, R. J. 1995. Tectonic evolution of the northern Ural Orogen. Journal of the Geological Society, London, 152, 903406. OWEN, H. G. 1988. Correlation of ammonite faunal provinces in the Lower Albian (mid-Cretaceous). In: WIEDMANN,J. & KULLURANN,J. (eds) Cephalopods past and present. Schweizerbart'sche Verlagsbuchhandlung, Stuttgart, 477-489. OXNEVAD, I. E. 1985. Anatomy of an early Cretaceous storm-wave influenced deep shelf succession (Janusfjellet Fm, Spitsbergen). In: International Association of SedimentoIogists European regional meeting June 1985, Leida, Spain. Univ. Autonoma, Barcelona, 632. OZIMKOWSrd, W. 1989. Joint fractures on the southern shore of Bellsund, Spitsbergen. Polish Polar Research, 10, 81-91. PADGET, P. 1954. Notes on some corals from late Palaeozoic rocks of inner Isfjorden, Spitsbergen. Norsk Polarinstitutt Skrifter, 100, 1-10. PAJCHEL, J., SELLEVOLL, M. A., GUTERCH, A., DUDA, S. & KOMBER, J. 1982. The Isfjorden profile. In: SELLEVOLL, M. A. (ed.) Seismic Crustal Studies on Spitsbergen 1978. University of Bergen Seismological Observatory, Bergen, 20-32.

504

REFERENCES

PALIB1N, J. 1906. Ueber die Entdeckung von Sequoia-Resten auf West-Spitzbergen.

Verhandlungen der Russisch-Kaiserlichen Mineralogischen Gesellschaft zu St. Petersburg, Series 2, 44, 411-414. PALMLrV, E. 1995. Seismic stratigraphy and tectonics of the Loppa High, Western Barents Sea. Acta Universitatis Stockholmiensis (Stockholm contributions in Geology), 43, 111 198. PANASENKO, G. D., KREMENETSKAYA,Y. O. & ARANOVICH,Z. I. 1987. [Earthquakes on Spitsbergen]. Mezhvedomstvennyy Geofizicheskiy Komitet pri Prezidiume AN SSSR 1987. PANOV, A. I. et al. 1996. Outline of the geology northern Dickson Land. In: KRASIL'SHCHIKOV,A. A. (ed.) Soviet Geological Research in Svalbard 1962-1992. Norsk Polarinstitutt Meddelelser, 139, 7. , et aL 1996. Geological study in eastern Nordenski61d Land (Kjellstr6mdalen, Danzigdalen and Agardhdalen areas). In: KRASIL'SHCHIKOV,A. A. (ed.) Soviet Geological Research in Svalbard 1962-1992. Norsk Polarinstitutt Meddelelser, 139, 74. - & NEPOMILUEV, V. F. 1996. Outline of the geology of the AgardhbuktaSassendalen area. In: KRASIL'SHCHIKOV,A. A. (ed.) Soviet Geological Research in Svalbard 1962-1992. Norsk Polarinstitutt Meddelelser, 139, 74. PARK, R. G. 1994. Early Proterozoic tectonic overview of the northern British Isles and neighbouring terranes in Laurentia and Baltica. Precambrian Research, 68, 65-79. PARKER, J. R. 1966. Folding, faulting and dolerite intrusions in the Mesozoic rocks of the fault zone of central Spitsbergen. Norsk Polarinstitutt Arbok 1964, 47-55. - - 1 9 6 7 . The Jurassic and Cretaceous sequence in Spitsbergen. Geological Magazine, 104, 487 505. PATERSON, W. S. B., KOERNER, R. M., FISHER, D., JOHNSON, S. J., CLAUSEN, H. B., DANSGAARD, W., BUCHER, P. (~z OESCHGER, H. 1977. An oxygen isotope climatic record from the Devon Island Ice Cap, Arctic Canada. Nature, 266, 508-511. PATTEN, W. 1926. New Ostracoderms of Spitsbergen. Geological Society of America Bulletin, 36, 237. PAVLOV, A. V. 1964. [Material composition of the ash of coal beds of some regions of Vestspitsbergen (on the data of spectral analysis)]. In: SOKOLOV, V. N. (ed.) Conference on the Geology of Spitsbergen, Leningrad 1964: Summary of Contributions. NIIGA, Leningrad, 29. 1964. [On the history of the formation and development of the Vestspitsbergen trough]. In: SOKOLOV, V. N. (ed.) Conference on the Geology of Spitsbergen, Leningrad 1964: Summary of Contributions. NIIGA, Leningrad, 20 22. - - 1 9 6 5 . [Ash content of coals of some regions of Spitsbergen]. Uchenyye Zapiski NIIGA: Regional'nays Geologiya, 8, 128-136. - - 1 9 6 5 . [Comparitive stratigraphy of the boreal Mesozoic of Europe] NIIGA, Moscow [with Latin nomenclature]. & EVDOKIMOVA, N. K. 1996. Coal-bearing deposits of Svalbard. In: KRASIL'SHCHIKOV,A. A. (ed.) Soviet Geological Research in Svalbard 1962- 1992. Norsk polarinstitutt Meddelelser, 139, 98. & PANTY, A. [. 1980. [The geology and coal content of Heer Land, Spitsbergen]. In: SEMEVSKIY,D. V. (ed.) Geologiya osadochnogo chekhla arkhipelaga Svalbard. Sbornik nauchnykh trudov [Geology of the Sedimentary Mantle of the Svalbard Archipelago. A Collection of Scientific Papers]. NIIGA, Leningrad, 81-94. & SOKOLOV,V. N. 1965. [Origin and history of the Vestspitsbergen Trough]. In: SOKOLOV, V. N. (ed.) Materialii po Geologii Shpitsbergena. NIIGA, Leningrad, 45-54. , KLITINA, L. V. & YEVDOKIMOVA,N. K. 1980. [Metamorphism of coals of the Storvola Formation of Spitsbergen]. In: SEMEVSKIY, D. V. (ed.) Geologiya Osadochnogo Chekhla Arkhipelaga Sval'bard. Sbornik Nauchnykh Trudov [Geology of'the Sedimentary cover of the SvaIbard Archipelago. A Collection of Scientific Papers]. NII GA, Leningrad, 100-109. , YEVDOKIMOVA,N. K. & KLITINA, L. V. 1983. [The occurrence and quality of coals in Bjornoya. In: KRASIL'SHCmKOV,A. A. & BASOV,V. A. (eds) ]The Geology of Spitsbergen." a Collection of Papers]. "Sevmorgeo", Leningrad, 102-109. PCHELINA, T. M. 1964. Stratigraphy and basic characters of the composition of the Mesozoic rocks of Vestspitsbergen. In: SOKOLOV,V. N. (ed.) Conference on the Geology of" Spitsbergen, Leningrad 1964." Summary' of Contributions. NIIGA, Leningrad, 8- l 0. - - 1 9 6 5 a . [On the Hauterivian Stage in West Spitsbergen]. Doklady Akademii Nauk SSSR, 163, 1234 1236. 1965b. [Stratigraphy and composition of the Mesozoic deposits of central Vestpitsbergen]. In: SOKOLOV, V. N. (ed.) Materialy po geologii Shpitsbergena [Materials' on the Geology of Spitsbergen]. NIIGA, Leningrad, 127 147. --t965c. [Mesozoic deposits around Van Keulenfjorden, Vestspitsbergen]. In: SOKOLOV, V. N. (ed.) Materialy po geologii Shpitsbergena [Materials on the geology of Spitsbergen]. NIIGA, Leningrad, 149-173. - - 1 9 6 7 . [Stratigraphy and some features of the composition of Mesozoic deposits of the southern and eastern areas of Spitsbergen]. In: SOKOLOV,V. N. (ed.) Materialy po stratigrafii Shpitsbergena [Materials on the stratigraphy of Spitsbergen]. NIIGA, Leningrad, 121-158. - - 1 9 7 2 a . [Concerning the age of sedimentary strata on Hopen]. In: SOKOLOV,V. N. t~s VASILEVSKAYA,N. D. (eds) Mezozoyskiye otlozheniya Sval'barda [Mesozoic Deposits of Svalbard]. NIIGA, Leningrad, 75-81. - - 1 9 7 2 b . [Triassic deposits on Bjornoya]. In: SOKOLOV, V. N. & VASILEVSKAYA, N. D. (eds) Mezozoyskiye otlozheniya Sval'barda [Mesozoic Deposits of Svalbard]. NIIGA, Leningrad, 5-20. - - 1 9 7 7 . [Permian and Triassic deposits of Edgeoya (Svalbard)]. In: Stratigraphy and Paleontology of the Precambrian and Paleozoic of Northern Siberia. A Collection of Scientific Papers. NIIGA, Leningrad, 59-71. 1980. [New data on the Triassic/Jurassic boundary beds of Svalbard]. In: SEMEVSKIY, D. V. (ed.) Geologiya Osadochnogo Chekhla Arkhipelaga Sval'bard. Sbornik Nauchnykh Trudov [Geology of the Sedimentary Mantle of the Svalbard Archipelago. A Collection of Scientific Papers]. NIIGA, Leningrad, 44-60.

- - 1 9 8 3 . [New material on the Mesozoic stratigraphy of the Spitsbergen Archipelago]. In: KRASlL'SHCHIKOV,A. A. & BAsov, V. A. (eds) Geologiya Shpitsbergena:

sbornik nauchnykh trudov [The Geology of Spitsbergen: a Collection of Papers]. PGO "Sevmorgeo", Leningrad, 121-141. - - 1 9 9 6 . Mesozoic stratigraphy and paleogeography of Svalbard. In: KRASIL'SHCHIKOV, A. A. (ed.) Soviet Geological Research in Svalbard 1962-1992. Meddelelser Norsk Polarinstitutt, 139, 60. PEACH, A. M. 1916. The pre-glacial platform and raised beaches of Prince Charles Foreland. Transactions of the Edinburgh Geological Society, 10, 289-307. PEDERSEN, G. 1979. Application of well data from Svalbard for palaeotemperature analysis of source rocks for petroleum in the Barents Sea. In: Norwegian Sea Symposium, (NSS/14). Norwegian Petroleum Society, Tromso, 1-13. PEDERSEN, G. S. 1977. Petroleum exploration in Svalbard, Spitsbergen. In: MUGGERIDGE, D. B. et al. (eds) POAC 77, Proceedings, 2. International Conference on Port and Ocean Engineering in Arctic Conditions, 4, 821 831. PEDERSEN, S. A. S. 1988. Model of structural events in the late Mesozoic platform break up between Greenland and Svalbard. In: DALLMANN,W. K., OHTA, Y. (~; ANDRESEN, A. (eds) Tertiary Tectonics of Svalbard. Norsk Polarinstitutt, Report Series, 46, 99-100. , HAKANSSON, E., HEINBERG, C. & MADSEN, L. 1992. Variations in the regional stress field through the Carboniferous to Tertiary development in North Greenland. In: DALLMANN, W. K., ANDRESEN, A. & KRILL, A. (eds), Post-Caledonian tectonic evolution of Svalbard. Norsk Geologisk Tidsskrift, 72[1,000 000 PEEL, J. S. & SMITH, M. P. 1988. The Wandel Valley Formation (Early-Middle Ordovician) of North Greenland and its correlatives. In: Cambrian-Jurassic Fossils, Trace Fossils and Stratigraphy from Greenland. Rapport, Gronlands Geologiske Undersogelse, 137, 61-92. PELTO, M. S. t~ WARREN, C. R. 1991. Relationship between tidewater glacier calving velocity and water depth at the calving front. Annals' of Glaciology, 15, 115 118. PERSSON, P. O. 1962. Plesiosaurians from Spitsbergen. Norsk Polarinstitutt Arbok 1961, 62-68. PETRENKO, V. M. 1963. [Some important finds of Early Triassic fauna in Spitsbergen]. Uchenyye Zapiski NIIGA: Paleontologiya i Biostratigrqfiya. [Scholarly Papers on Palaeontology and Biostratigraphy], 3, 50-54. PEUCAT, J. J., OHTA, Y., GEE, D. G. &; BERNARD-GRIFEITHS,J. 1989. U-Pb, Sr and Nd evidence for Grenvilliau and latest Proterozoic tectonothermal activity in the Spitsbergen Caledonides, Arctic Ocean. Lithos, 22, 275-285. --, TISSERANT,D., CABY, R. & CLAUER, N. 1985. Resistance of zircons to U-Pb resetting in the prograde metamorphic sequence of Caledonian age in East Greenland. Canadian Journal of Earth Sciences, 22, 330-338. PEWE, T. L., ROWAN, D. E. & PEWE, R. H. 1981. Engineering geology of the Svea lowland, Spitsbergen, Svalbard. Frost i Jord, 23, l 11. PEIRMAN, S. & MILLIMAN,J. D. 1987. Morphology, geology and oceanography of the Hinlopen Strait and Trough, Svalbard, Norway (extended abstract). Polar Research, 5, 297-298. PFIRMAN, S. L. & SOLHEIM,A. 1989. Subglacial metlwater discharge in the open-marine tidewater glacier environment: observations from Nordaustlandet, Svalbard archipelago. Marine Geology, 86, 265-281. PmHPP, H. 1914. Ergebnisse der W. Filchnerschen Vorexpedition nach Spitzbergen 1910. Geologische Beobachtungen. Petermanns Mitteilungen Erganzung, 179, 13-45. PICKARD, N . A . H . , EILERTSEN, F . , HANKEN, N.-M., JOHANSEN, T. A., LONOY, A., NAKREM, H. A., NILSSON, I., SAMUELSBERG, T. G. • SOMERVILLE, I. D. 1996. Stratigraphic framework of Upper Carboniferous (Moscovian Kasimovian) strata in Btinsow Land, central Spitsbergen: palaeogeographic implications. Norsk Geologisk Tidsskrift, 76, 169-186. PICKEmNG, K. T. & SMITH, A. G. 1995. Arc and back arc basins in the Early Paleozoic lapetus Ocean. The Island Arc, 4, 1 67. PICKTON, C. A. G. 1981. Palaeogene and Cretaceous dropstones in Spitsbergen. In: HAMBREY, M. J. & HARLAND, W. B. (eds) Earths pre-Pleistocene glacial record. Cambridge University Press, 567- 569. , HARLAND,W. B., HUGHES, N. F. & SMITH, D. G. 1979. Mesozoic stratigraphy of Eastern Svalbard: a reply. Geological Magazine, 116, 55-61. PIEPJOHN, K. & THIED1G, F. 1992. Tektonische Entwicklung des kaledonischen Basements und der postkaledonischen Old Red-Sedimente in NW-Spitsbergen (Liefdefjorden-Woodfjorden). Stuttgarter Geographische Studien, 117, 13 35. - & - - 1 9 9 4 . Geologie und tektonische Entwikhlung der Germaniahalvoya, Haakon VII Land, NW-Spitsbergen (Svalbard). ZeitschriJt .far Geomorphologie N.F., 97, 19-29. , HARLING, U., KEEL, S., MOLLER, M. & THIEDIG, F. 1992. Geologische Neukartiering der Germaniahalvoya, Haakon VII Land, NW-Spitsbergen, Svalbard. Stuttgarter Geographische Studien, 117, 37-54. PIPER, D. J. W. & PORRITT 1966. Some pingos in Spitsbergen. Norsk Polarinstitutt Arbok 1965, 81-84. , HARLAND,W. B. & CUTBILL,J. L. 1970. Recording of geological data in the field using forms of input to the IBM Handwriting Reader. In: Data processing Biology~Geology. Systematics Association, 17-38. PIPER, J. D. A. 1973. Latitudinal extent of Late Precambrian glaciations. Nature, 244, 342-344. - - 1 9 8 7 . Palaeomagnetism and the Continental Crust. Open University Press and Halstead Press. PISKAREV, A. L. & RAKHIN, V. A. 1981. [The nature of magnetic and gravitational anomalies in the eastern Svalbard massif according to the results of geophysical research on Bjornoya]. In: Morskiye Geofizicheskiye Issledovaniya v Arktike [Marine Geophysical Investigations in the Arctic]. Leningrad, 41-45. PITMAN, W. C. & TALWANI, M. 1972. Sea-floor spreading in the North Atlantic. Geological Society of America Bulletin, 83, 619-646.

REFERENCES PLAYFORD, G. 1962. Lower Carboniferous microfloras of Spitsbergen. Part 1. Palaeontology, 5, 550-618. 1963. Lower Carboniferous microfloras of Spitsbergen. Part II. Palaeontology, 5, 619-678. POGARSKAYA, I. A. & GUREVICH, Y. L. 1988. [Paleomagnetism of Devonian rocks, Spitsbergen]. In: KHRAMOVA. N. (ed.) Paleomagnetism and Accretion Tectonics. VNIGRA, Leningrad, 6-18. POLARSTERN SHIPBOARD SCIENTIFIC PARTY 1988. Breakthrough in Arctic deep-sea research: the R/V Polarstern Expedition 1987. L O S (Transactions of the American Geophysical Union), 665, 676. POLYAK, L., LEHMAN, S. J., GATAULLIN, V. & JULL, A. J. T. 1995. Two-step deglaciation of the southeastern Barents Sea. Geology, 23, 567-571. POMPECrd, J. F. 1899. Marines Mesozoikum yon Krnig Xarls-Land. 0fversigt af Konglia. Vetenskaps Academiens Frrhandlingar, 56, 449 464. - - - 1 9 0 1 . Ueber Aucellen und Aucellen-fihnliche Formen. Neues Jahrbuch far Mineralogie, Geologic und PaMontologie, 14, 319-368. PONOMAREV, T. N. 1935. [A problem of fuel]. In: POLKANOVA, A. A. Kontury geologicheskoy problemy Severa Evropeyskoi chasti SSSR. VNIGRI, Geologich. Problemy Soyuza, Leningrad-Moscow, 28-59. PORTMAYN, J. P. 1969. Some Superficial deposits within the map sheet Adventdalen, Vestspitsbergen. Norsk Polarinstitutt Meddelelser, 98, 5-16. POSTNOV, I. S. 1983. [Mineral waters of Spitsbergen]. In: NEIZVESTNOV,YA. V. & SEMEVSrdY, D. V. (eds) Gidrogeologiya, Inzhenernaya Geologiya, Geomorfologiya Arkhipelaga Shpitsbergen [The Hydrogeology, Engineering Geology and Geomorphology of the Spitsbergen Archipelago]. PGO "Sevmorgeo", Leningrad, 5-15. POULSEN, C. 1957. Quelques remarques sur le Cambrien Infrrieur et l'Eocambrian du Groenland et d'autres regions septentrionales. In: Les Relations entre Prdcambrien et Cambrien. Probldmes des sOries intermddiares. Colloques Internationaux du Centre National de la Recherche Scientifique, 76, Paris 27 Juin gt 4 Juillet 1957, 25-31. POZDEYEV, V. S. 1964. [Seismic survey work on the Spitsbergen Archipelago]. In: SOKOLOV,V. N. (ed.) Conference on the Geology of Spitsbergen, Leningrad 1964." Summary of Contributions. NIIGA, Leningrad, 29-31. - - 1 9 6 5 . [Seismic surveys in Vestspitsbergen]. In: SOKOLOV,V. N. (ed.) Materialy po Geologii Shpitsbergena. NIIGA, Leningrad, 285-292. [English translation by J. E. Bradley, National Lending Library for Science and Technology, Boston Spa, England.] PRAY, J. R., MAHER, H. D. JR. & WELBON,A. I. 1992. Ruminations on Tuttle lamellae (fluid inclusion planes) in Carboniferous strata from Bellsund and St. Jonsfjorden, western Svalbard. In: DALLMANN,W. K., ANDRESEN, A. & KRILL, A. (eds) PostCaledonian Tectonic Evolution of Svalbard. Norsk Geologisk Tidsskrift, 72, 77-82. PRESTON, J. 1959. The geology of the Snofjella and Dovrefjella in Vestspitsbergen. Geological Magazine, 96, 5-57. PRESWIK, T. 1978. Cenozoic plateau lavas of Spitsbergen- a geochemical study. Norsk Polarinstitutt Arbok 1977, 129-143. PRESTWICH,J. 1860. Description of Gravels from Spitsbergen collected by Mr Lamont. Quarterly Journal of the Geological Society of London, 16, 438. PRIGMORE,J. K., BUTLER,A. J. & WOODCOCK,N. H. 1997. Rifting during separation of Eastern Avalonia from Gondwana: Evidence from subsidence analysis. Geology, 25, 203-206. PRINGLE, I. R. 1973. Rb-Sr age determinations on shales associated with the Varanger ice age. Geological Magazine, 109, 465-472. QUENSTEDT,W. 1926. Mollusken aus den Redbay- und Greyhookschichten Spitzbergen. Skrifter om Svalbard og Ishavet, 11, 1-107. - - 1 9 2 7 . Uber fossilerhattung und Tektonik in Devonian Spitzbergen. Zeitschrift der Deutschen Geologischen Gesellschaft, Monatsberichte. RAABEN, M. YE. 1960. On the stratigraphical position of the beds with Gymnosolen. In: International Geological Congress, Report of 21st Session. International Geological Congress, Norden, 125-131. - - 1 9 6 7 . [Geological research in Spitsbergen]. Izvestiya A N SSSR, Seriya Geologicheskaya, 2, 50-54. - & LAVRUSHIN,YU. A. 1967. Geological research on Spitsbergen. Bulletin of the Academy of Sciences, St. Petersburg, 2, 50-54. - t~ ZABRODIN,V. YE. 1969. [Biostratigraphic characteristics of the upper Riphean in the Arctic]. Doklady Akademii Nauk SSSR, 184, 676-679. -& 1972. [Upper Riphean Problematic Algae; Stromatolites; Oncolites], Akademiya Nauk SSSR, Moscow. [Geol. Inst. translation]. RAASCH, G. 1961. Geology of the Arctic. Vols. 1 & 2, University of Toronto Press. RABOT, C. 1901. La grologie de la terre du Roi Charles. Grographie, 4, 379-383. - - 1 9 1 7 . Nouvelles exploration grologique au Spitsberg. G~ographie, 000-000. RACHOCKI, A. H. & CHURCH,M. (eds) 1990. Alluvial Fans. A Field Approach. Wiley, Chichester. RADWANSKI, A. t~ BIRKENMAJER,K. 1977. Oolitic/pisolitic dolostones from the Late Precambrian of south Spitsbergen: their sedimentary environment and diagenesis. Acta Geologica Polonica, 27, 1-39. RAMOND, G. & DOLEUS, G. 1894. Grologie c]u Spitsberg, ~t propros de la mission de "La Manche". Notes et rrsum&. Feuille des Juenes Naturalistes, 286, 145 147 and 287, 161-167 and 288, 117-185. RApp, A. 1960. Talus slopes and mountain walls at Tempelfjorden, Spitsbergen. Norsk Polarinstitutt Skrifter, 119, 1-96. RASMUSSEN, E. & FJELDSKAAR,W. 1996. Quantification of the Pliocene-Pleistocene erosion of the Barents Sea from present-day bathymetry. In: SOLHEIM,A. et al. (eds.) Global and Planetary Change, 12, 119-134. , SKOTT, P. H. & LARSEN, K.-B. 1995. Hydrocarbon potential of Bj~rnoya West Province, western Barents Sea margin. In: HANSLIEN, S. (ed.) Petroleum Exploration and Exploitation in Norway. NPF Special Publication, 4. Amsterdam, Elsevier, 277-286.

505

RATLIFF, R. A., MORRIS, A. P. & DODT, M. E. 1988. Interaction between strike-slip and thrust-shear: deformation of the Bullbreen Group, central-western Spitsbergen. Journal of Geology, 96, 339-349. RAVICH, M. G. 1979. Is there an early Precambrian granite-gneiss complex in northwestern Spitsbergen? Norsk Polarinstitutt Skrifter, 167, 9-28. RAVN, J. P. J. 1922. On the mollusca of the Tertiary of Spitsbergen. Resultater Norske Spitzbergenekspeditioner, 1, 1-28. RAWSON, P. F. 1982. New Arctocephalitinae (Ammonoidea) from the Middle Jurassic of Kong Karls Land. Geological Magazine, 119, 95-100. RAYMOND, C. F. 1987. How do glaciers surge? Journal of Geophysical Research, 92, 9121-9134. READING, H. G. 1980. Characteristics and recognition of strike-slip fault systems. Special Publications of the International Association of Sedimentologists, 4, 7-26. RECTOR, S. 8z BJORNERUD,M. 1987. Quartz petrofabric and microstructural analysis of Antoniabreen Sequence rocks east of Recherchebreen, west Spitsbergen. Geological Society of America, Abstracts with Programs, 19, 814. REED, W. E. 1991. Genesis of calcretes in the Devonian Wood Bay Group, Dicksonland, Spitsbergen. Sedimentary Geology, 75, 149-161. , DOUGLASS, D. N. t~; LAMAR, D. L. 1987. Devonian Old Red Sandstone sedimentation and tectonic history of the Billefjorden Fault Zone, Spitsbergen. Geologic en Mijnbouw, 66, 191-199. REEMST, P., CLOETINGH,S. • FANAVOLL,S. 1994. Tectonostratigraphic modelling of Cenozoic uplift and erosion in the south-western Barents Sea. Marine and Petroleum Geology, 11, 478-490. REMANE, J., BASSETT, M. G., COWIE, J. W., GORBANDT, K. H., LANE, H. R., MICHELSEN, O. & WANG, N. 1996/7? Revised guidelines for the establishment of global chronstratigraphic standards by the International Commission on Stratigraphy. Episodes, 19, 77-81. REMPP, G. 1914. Die mikroseismische Unruhe nach Registrierungen der deutschen geophysikalischen Station Advent Bay (Spitzbergen) 1911-12. Gerlands Beitrage zur Geophysik, 13, 100-102. - - 1 9 1 4 . Aufstellung und Betrieb eines Seismographen auf der deutschen geophysikalischen Station Adventbay (Spitzbergen) 1911-12. Gerlands Beitrage zur Geophysik, 13, 91-99. RESVOLL-HOLMSEN,H. 1925. [On the flora of Svalbard at present and in earlier periods of the Earth]. Norges Tidsskrift om vdrt Land., 4, 113-119. REUSCH, B. H. 1891. [Striations and moraine debris demonstrated in Finnmark from a period much older than the "ice age"]. Norges geologiske undersokelse, .flrbok 1891, 78-85. - - 1 9 1 3 . The coal resources of Norway and the Arctic islands north of Europe. In: The Coal Resources t?f the World, 3, Toronto, 1139-1140. RIIs, F. & FJELDSKAAR, W. 1992. On the magnitude of the Late Tertiary and Quaternary erosion and its significance for the uplift of Scandinavia and the Barents Sea. In: LARSEN,R. M., BREKKE,H., LARSEN,B. T. & TALLERAAS,E. (eds) Structural and Tectonic Modelling and its Application to Petroleum Geology. Norwegian Petroleum Society (NPF), Special Publication, Part 1 (Proceedings of Norwegian Petroleum Society Workshop, 18-20 October 1989, Stavanger, Norway). Elsevier, Amsterdam, 163-185. - & VOLLSET,J. 1988. A preliminary interpretation of the Hornsund Fault Complex between Sorkapp and Bjornoya. In: DALLMAN,W. K., OHTA,Y. & ANDERSON,A. (eds) Tertiary Tectonics ofSvaIbard. Norsk Polarinstitutt, Report Series, 46, 91-92. - - , - - & SAND, M. 1985. Tectonic development of the western margin of the Barents Sea and adjacent areas. NPD Contributions, 22. Oljedirektoratet, Stavanger. --, -& 1986. Tectonic development of the western margin of the Barents Sea and adjacent areas. In: HALBOUTV,M. T. (ed.) Future Petroleum Provinces of the World. Memoirs of the American Association of Petroleum Geologists, 40, 661-675. RINGSET, N. 1988. The fold and thrust system of Midterhukfjellet, Bellsund. In: DALLMANN, W. K., OHTA, Y. & ANDRESEN, A. (eds) Tertiary Tectonics of Svalbard. Norsk Polarinstitutt, Report Series, 46, 39-42. - & ANDRESEN, A. 1988. The Gipshuken Fault System- evidence for Tertiary thrusting along the Billefjorden Fault Zone. In: DALLMANN,W. K., OHTA, Y. & ANDRESEN, A. (eds) Tertiary Tectonics of Svalbard. Norsk Polarinstitutt, Report Series, 46, 67-70. RITTER, U., DUDDY, I., MORK, A., JOHANSEN,H. & ARNE, D. 1996. Temperature and uplift history of Bjornoya (Bear Island), Barents Sea. Petroleum Geoscience, 2, 133-144. ROBERT, E. 1840-1850. Grologie, minrralogie et m&allurgie. In: GAIMARD, P. (ed.) Voyages en Scandinavie, en Lapponie, au Spitzberg et aux Ferfe, pendant les anndes 1838, 1839 et 1840 sur la corvette La Recherche, 4, 87-118 and 26, 129-131. Paris. ROBERTS,D. & GEE, D. G. 1985. An introduction to the structure of the Scandinavian Caledonides. In: GEE, D. G. & STURT, B. A. (eds) The Caledonide OrogenScandinavia and Related Areas. Wiley, 55-68. RONNERT, L. t~ LANDVIK, S. Y. 1993. Holocene glacial advances and moraine formation at Albrecbreen, Edgeoya, Svalbard. Polar Research, 12, 57-63. RONNEVIK,H. C. 1981. Geology of the Barents Sea. In: ILLING,L. V. & HOBSON,G. D. (eds) Petroleum Geology of the continental Shelf of the Northwest Europe. Institute of Petroleum, London, 395 406. - & JACOBSEN,H. P. 1984. Structural highs and basins in the western Barents Shelf. In: SPENCER,A. M. et al. (eds) Petroleum Geology of the North European Margin. Graham & Trotman, London, 19-32. - - , BESKOW,B. & JACOBSEN,P. 1982. Structural and stratigraphic evolution of the Barents Sea. In: EMBRY, A. F. & BALKWELL,H. R. (eds) Arctic Geology and Geophysics. Canadian Society of Petroleum Geologists, Memoirs, 8, 431-440. - - , EGGEN,S. & VOLLSET,J. 1983. Exploration of the Norwegian Shelf. In: BROOKS,J. (ed.) Petroleum Geochemistry and Exploration of Europe. Geological Society, London, Special Pubhcations, 12, 71--93.

506

REFERENCES

ROOTS, W. D. & SRIVASTAVA,S. P. 1984. Origin of the marine magnetic quiet zones in the Labrador and Greenland Seas. Marine Geophysical Researches, 6, 395-408. ROSENKP,ANZ, A. 1942. Sitzung des [Paleoz/in] Klubs (d/inisch) Meddelelser. Dansk Geologisch Frreningen, 10, 277-278. Ross, C. A. 1963. Standard Wolfcampian Series (Permian), Glass Mountains. Memoirs of the Geological Society of America, 88. - - 1 9 6 5 . Fusulinids from the Cyathophyllum Limestones, Central Vestspitsbergen. Contributions from the Cushman Foundation for Foraminiferal Research, 16, 74-86. ROWLEY, D. B. & LOTTES, A. L. 1988. Plate-kinematic reconstructions of the North Atlantic and Arctic: Late Jurassic to Present. Tectonophysics, 155, 73-120. ROZYCKI, S. Z. 1959a. Geology of the north-western part of Torell Land, Vestspitsbergen. Part I. Studia Geologica Poloniea, 2, 1-38 [in Polish]. - - 1 9 5 9 b . Geology of the north-western part of Torell Land, Vestspitsbergen. Part II. Studia Geologica Polonica, 2, 39-94 [in English]. RUDBERG, S. 1986. Present-day geomorphological procession, Prins Oscars Land, Svalbard with appendix: Recent transgression in Svalbard? Geografiske Anna&r, 68A, 41-63. RYrG, E. 1972. Rayleigh wave dispersion and crustal structure: the Norwegian Sea and adjacent areas. Norsk Polarinstitutt Arbok 1970, 169-177. RYGIELSKL W. 1988. [Geomorphology of gypsum/anhydrite rocks around Petuniabukta, central Spitsbergen]. In: JAHN, A., PEREYMA, J. & SZCZEPANKIEWICZSZMYRKA, A. (eds) XV Sympozjum Polarne. Stan obecny i wybrane problemy polskich badan polarnych, Wroclaw 19-21 May 1988. Wydawnictwo Uniwersytetu Wroclawskiego, Warsaw, 38 44. SAKAGAMI, S. 1992. Notes on the Permian bryozoans from the Kapp Starostin Formation at Festningen route, Spitsbergen. In: NAKAMURA, K. (ed.) Investiga-

tions in the Upper Carboniferous-Upper Permian succession of West Spitsbergen 1989-1991. Hokkaido University, Sapporo, 39-58. SAKS, V. N. (ed.) 1976. [Stratigraphy of the Jurassic System of the North of the USSR], Nauka, Moscow. & SHULGINA,N. I. 1974. Basic problems of the Upper Volgian, Berriasian and Valanginian stratigraphy of the Boreal zone. Acta Geologica Polonica, 24, 543-560. SALES, J. 1988. Tertiary deformation of Svalbard: regional relationships, critical areas, alternative models. In: DALLMAN,W. K., OHTA, Y. & ANDRESEN, A. (eds) Tertiary tectonics of Svalbard. Extended abstractsfrom symposium held in Oslo 26-27 April 1989. Norsk Polarinstitutt Rapport Serie, 46, 109-110. SALTER, J. W. 1860. Notes on the fossils from Spitzbergen. Quarterly Journal of the Geological Society of London, 16, 439-442. SALWCSEN, O. 1977. Radiocarbon datings and the extension of the Weichschian icesheet in Svalbard. Norsk Polarinstitutt Arbok 1976, 209-224. - - 1 9 7 8 . Holocene emergence finds of pumice, whale bones, and driftwood at Svart Knausflya, Nordaustlandet. Norsk Polarinstitutt Arbok 1977, 217-228. - - 1 9 7 9 . The last deglaciation of Svalbard. Boreas, 8, 229-231. & MANGERUD,J. 1991. Holocene shoreline displacement at Agardhbukta, eastern Spitsbergen, Svalbard. Polar Research, 9, 1-7. & NYDAL, R. 1981. The Weichselian glaciation in Svalbard before 15,000B.P. Boreas, 10, 433-446. & OSTERHOLM,H. 1981. Radiocarbon dated raised beaches and glacial history of northern Spitsbergen coast, Svalbard. Polar Research, 1, 97-115. & SLETTEMARK,O. 1994. Past glaciation and sea levels on Bjornoya, Svalbard. Polar Research, 14, 245 25l. -& WINSNES, T. S. 1987. Geological Map of Svalbard. 1."100,000. Sheet ClOG Braganzavdgen. Norsk Polarinstitutt Temakart, 4. , ADRIELSSON, L., HJORT, C., JOPHANSSON, K., KELLY, M., LANDVIK, J. Y. & RONNERT, L. 1992. Ice movements in eastern Svalbard. LUNDQUA Report, 35, 9-16. , , , KELLY, M., LANDWK, J. Y. & RONNERT, L. 1995. Dynamics of the last glaciation of eastern Svalbard inferred from glacier-movement indicators. Polar Research, 14, 141-152. , FORMAr~, S. L. & MrLLER, G. H. 1992. Thermophilus molluscs on Svalbard during the Holocene and their paleoclimatic implications. Polar Research, 11, 1-10. , LAURITZEN, Q~l.& MANGERUD, J. 1983. Karst and karstification in gypsiferous beds in Mathiesondalen, Central Spitsbergen, Svalbard. Polar Research, 1, 83-88. SAMOmOWCH, R. L. 1913. [Account of the coal deposits in Spitsbergen belonging to the merchant house "'Grumant" A. G. Agafelov & Co., Jbr mining work in Spitsbergen by the mining engineer R. L. Samoilovich, leader of the mining expedition to Spitsbergen in 1913]. St Petersburg. - - 1 9 2 0 . [A scheme for the establishment of collieries upon the Russian territory of Grumant (Spitsbergen)]. Trudy Severnoy Nauchno-Promyslovoi Ekspedicfi, 1, 1-32. - - - , ADADUROV, V. A. & SIDOROV,A. N. (eds) 1927. [The coal industry of Grumant (Spitsbergen)]. A collection of articles. Leningrad. SANDAL, S. T. & HALVORSEN, E. 1973. Late Mesozoic palaeomagnetism from Spitsbergen: implications for continental drift in the Arctic. Physics of the Earth and Planetary Interiors, 7, 125-132. SANDEORD,K. S. 1925. The Oxford University Arctic Expedition 1924. II. Geology and Glaciology. Geographical Journal, 66, 114-120. - - 1 9 2 6 . The geology of North-East Land (Spitsbergen). Quarterly Journal of the Geological Society of London, 82, 615-665. - - 1 9 2 9 . The glacial conditions and Quaternary history of North-East Land. Geographical Journal, 74, 1-30. - - 1 9 5 0 . Observations on the geology of the northern part of North-East Land (Spitsbergen). Quarterly Journal of the Geological Society of London, 105, 461-49 t. -

-

-

-

-

-

-

-

-

-

- - 1 9 5 4 . The geology of Isis Point, North-East Land (Spitsbergen). Quarterly Journal of the Geological Society of London, 110, 11-20. - - 1 9 5 6 . The stratigraphy and structure of the Hecla Hoek Formation and its relationship to a subjacent metamorphic complex in North-East Land (Spitsbergen). Quarterly Journal of the Geological Society of London, 112, 339-362. - - 1 9 6 3 . Exposures of Hecla Hoek and younger rocks on the north side of Wahlenbergfjorden, Nordaustlandet (Svalbard). Norsk Polarinstitutt Arbok 1962, 7-23. SJETTEM, J., POOLE, D., ELLtNSEN, K. E. & LOVLIE, R. 1990. Shallow Drilling Bjornoya West 1989. Appendix Volume 2 - Quaternary Sediments and Glacial Geology. I K U Report 21.3465. , Buc_a3E, T., FANAVOLL,S., GOLL, R. M., MORK, A., MORK, M. B. E., SMELROR, M. ~,~ VERDENIUS, J. O. 1992. Cenozoic margin development and erosion of the Barents Sea: core evidence from southwest of Bjornoya (abstract). In: International Conference on Arctic margins, 2-4 September 1992. ICAM, Anchorage, Alaska, 61. SAvE-SODERBERGH, G. 1935. On the dermal bones of the head in labyrinthodont Stegocephalians and primitive Reptilia. Meddelelser om Gronland, 98. - - 1 9 3 6 . On the morphology of Triassic Stegocephalians from Spitsbergen, and the interpretation of the endocranium in the Labyrinthodontia. Kungliga Svenska Vetenskapsakademiens Handlingar, 16, Stockholm. - - t 9 3 7 . On the dermal skulls of Lyrocephalus, Aphaneramma, and Benthosaurus, Labyrinthodonts from the Triassic of Spitsbergen and N. Russia. Bulletin of the Geological Institution of the University of Uppsala, 27, 209-211. - - 1 9 4 1 . Remarks on "Downtonian" and related problems. Geologiska FO?eningens Stockholm FO'rhandlingar, 63, 229-244. SAVOSTIN, L. A. • BATURIN,D. G. 1986. [Seismostratigraphy and Cenozoic history of the continental margin of the Greenland Sea in the area around the southern termination of the Spitsbergen archipelago]. Doklady Akademii Nauk SSSR, 291, 1458-1462. SAWAGAKI, T. & KOAZE, T. 1996. Land slides and relict ice margin landforms in Adventdalen, central Spitsbergen. Polar Research, 15, 139-152. SCHELLVIEN, E. 1908. Monographie der Fusulinen. Nach dem Tode des Verfassers herausg, und fortges, yon H. v. Staff. T. 1. Die Fusulinen des russisch-arktischen Meeresgebietes. Palaeontographica, 55, 145 194. SCHENCK, A. 1890. Jurassiche HOlzer yon Green Harbour auf Spitzbergen. Kungliga Svenska Vetenskapsakademiens Ofvers. Arg., 47, 5-10. - - 1 9 3 7 . Kristallin und Devon im nordlichen Spitzbergen. Geologische Rundschau, 124. SCHERMERHORN, L. J. G. 1974. Late Precambrian mixtites: glacial and/or non glacial? American Journal of Science, 274, 673-824. SCHETELIG,J. 1912. Les formations primitives - exploration du Nord-Ouest du Spitsberg entreprise sous les auspices de S.A.S. le Prince de Monaco par la Mission Isachsen. R~sultats des Compagnes Scientifiques, Monaco, Fasc. 43, 1-32. SCHLOEMER-JAGER, A. 1958. Altterti~ire Pflanzen aus Fl6zen der Brogger-Halbinsel Spitzbergens. Palaeontographica, 104, 39 103. SCHLOTER, H. U. & HINZ, K. 1978. The continental margin of west Spitsbergen. Polarforschung, 48, 151-169. SCHMIDT, K. 1966. Chapter CIII. In: LOTZE, F. & SCHMIDT, K. (eds) Prdkambrium. Handbuch der Stratigraphischen Geologie, 13, F. Enke, Stuttgart, 201-206 [in German]. SCHOPF, J. W. 1968. Microflora of the Bitter Sprining Formation, Late Precambrian, central Australia. Journal of Paleontology, 42, 651-688. SCHOPE, J. W. & KLEIN, C. (eds) 1992. The Proterozoic Biosphere: A Multidisciptinary Study. Cambridge University Press. SCHOU, L., MORK, A. & BJOROY, M. 1984. Correlation of source rocks and migrated hydrocarbons by GS-MS in the Middle Triassic of Svalbard. Organic Geochemistry, 6, 513-520. SCHULTZE, H.-P. 1968. Palaeoniscoidea-Schuppen aus dem Unterdevon Australiens und Kanadas und aus dem Mitteldevon Spitzbergens. Bulletin of the British Museum (Natural History), Geology, 16, 343-365. SCHUMACHER, J. C., OHTA, Y. & BUCHER, K. 1995. Petrology of spinel-rich segregations in gneisses of the Smeerenburgfjorden area, NW Spitsbergen. Terra Abstracts, 7, 314. SCHWEITZER,H.-J. 1965. 0ber Bergeria mimerensis und Protolepidodendropsispulchra aus dem Devon Vestspitzbergens. Palaeontographica, Bl15, 117-138. - - 1 9 6 7 a . Die Oberdevon-Flora der B~ireninsel 1. Pseudobornia ursina Nathorst. Palaeontographica, 120, 116-137. - - 1 9 6 7 b . Ein Riesenschachtelhalm aus dem Oberdevon, Pseudobornia ursina Umschau, 67, 196-197. - - 1 9 6 8 . Pflanzenreste aus dem Devon Nor-Vestspitzbergens. Palaeontographica, B123, 43-73. - - 1 9 6 9 . Die Oberdevon-Flora der B~ireninsel 2. Lycopodiinae. Palaeontographiea, 126, 101-137. - - 1 9 7 4 . Die "Terti~iren" Koniferen Spitzbergens. Palaeontographica, B149, 1-89. - - 1 9 7 8 . Paleoecological conditions of the Lower Tertiary flora of Spitsbergen. American Association of Petroleum Geologists, Abstracts with Programs, 10. - - 1 9 9 2 . Vorliiufiger Bericht fiber die w~thrend der geowissenschaftlichen Spitzbergen-Expedition 1990 (SPE 90) erzielten pal~iobotanischen Ergebnisse. Stuttgarter Geographiske Studien, 117, 55-72. SCHYTT, V. 1964. Scientific results of the Swedish glaciological expedition to Nordaustlandet, Spitsbergen 1957 and 1958. Geografiska Annaler, 46, 243-248. - - 1 9 6 9 . Some comments on glacier surges in eastern Svalbard. Canadian Journal of Earth Sciences, 6, 867-873. --, HOPPE, G., BLACKE, W. ~; GROSSWALD, M. G. 1968. The extent of the Wtirm glaciation in the European Arctic. A prelimary report about the Stockholm University Svalbard Expedition 1966. International Association of Scientific Hydrology, IUGG, Committee on Snow and Ice, Publications, 79, 207-216. 2 8 ,

1 1 2

REFERENCES ScooN, J. H. & GEE, D. G. 1966. A note on the occurrence of eclogites in Spitsbergen. Norsk Polarinstitutt Arbok 1964, 240-241. SCORESBV,W. 1820. An Account of the Arctic Regions, with a History and Description of

the Northern Whale-Fishery, Appendix VL Notice Respecting the Minerals of Spitzbergen. Edinburgh. SCOTT, R. H. 1872. Heer's Flora Fossilis Arctica. Geological Magazine, 9, 69-72. SCRUTTON, C. T., HORSFIELD, W. T. & HARLAND, W. B. 1976. Silurian fossils from western Spitsbergen. Geological Magazine, 113, 519-523. SELLEVOLL,M. (ed.) 1982. Seismic Crustal Studies on Spitsbergen. Bergen: University of Bergen Seismological Observatory. - - , DUDA, S. J., GUTERCH,A., PAJCHEL,J., PERCHUC,E. & THYSSEN,F. 1991. Crustal structure in the Svalbard region from seismic measurements. Tectonophysics, 189, 55-71. SELLiNg, O. H. 1944. On cupressoid root remains of Mesozoic age from the Arctic. Arkiv f t r Betanic, 31A. Uppsala. - - 1 9 4 5 . A megaspore from the Mesozoic of Hope Island, Svalbard. Botaniska Notiser, 1945, 44-48. - - 1 9 5 1 . On Protojuniperoxylon arcticum. Journal of Paleontology, 25, 538-539. SEMEVSKIV, D. V. 1965. [an the age of the Sverre Volcano]. In: SO~:OLOV,V. N. (ed.) Materialy po geologii Shpitsbergena. Institute for Geology of the Arctic, Leningrad, 272-275. - - 1 9 6 5 . [Paleontological characteristics of the marine terranes of Van Mijenfjorden and Billefjorden]. In: SOKOLOV,V. N. (ed.) Materialy po geologfi Shpitsbergena. Institute for Geology of the Arctic, Leningrad, 222-231. (ed.) 1980. [Geology of the Sedimentary Platform Cover of the Svalbard Archipelago. A Collection of Scientific Papers]. NIIGA, Leningrad [in Russian]. - - 1 9 9 6 . Pleistocene deposits, neotectonics and paleogeography of the Spitsbergen archipelago. In: DALLMANN, W. K. & KRASIL'SHCHIKOV,A. A. (eds). Norsk Polarinstitutt Meddelelser, 139, 68. -& SHKATOV,YE. P. 1965. [Geomorphology of Nordenskirld Land, Vestspitsbergen]. In: SOKOLOV,V. N. (ed.) Materialy po geologii Shpitsbergena. Institute for Geology of the Arctic, Leningrad, 232-240. -& - - 1 9 7 0 . [The influence of young tectonic movements on the formation of the coast of the archipelago of Spitsbergen]. Uchenyye Zapiski NIIGA: Paleontologiya i Biostratigrafiya [Scholarly Papers on Regional Geology], 18, NIIGA, Leningrad, 46-47. & 1980. [Quaternary fossil invertebrate fauna from the Svalbard Archipelago]. In: SEMEVSKIY, D. V. (ed.) Geologiya Osadochnogo Chekhla Arkhipelaga Sval'bard. Sbornik Nauchnykh Trudov [Geology of the Sedimentary Platform Cover of the Svalbard Archipelago. A Collection of Scientific Papers]. NIIGA, Leningrad, 129-133. -& 1996. Quaternary deposits, geomorphology and recent tectonics on the north coast of Van Mijenfjorden and the east coast of Billefjorden. In: KRASIL'SHCrtlKOV,A. A. (ed.) Soviet Geological Research in Svalbard 1962-1992. Norsk Polarinstitutt Meddelelser, 139, 67. -& 1996. Quaternary deposits and geomorphology of some areas of Spitsbergen. In: KRASIL'SHCmKOV,A. A. (ed.) Soviet Geological Research in Svalbard 1962-1992. Norsk Polarinstitutt Meddelelser, 139, 68. SEN, J. 1958. On the megaspores described by Nathorst from the Upper Devonian of Bear Island. Geologiska Frreningens Stockholm Frrhandlingar, 80, 141-148. SERANNE, M., CrtAtWET, A., SECURE'r, M. & BRUNEL, M. 1989. Tectonics of the Devonian collapse-basins of western Norway. Bulletin de la Soci~tO Gdologique de France, 5, 489. SEWARD, A. C. 1931. Plant Life through the Ages. Cambridge University Press. SEXTON, D. J., DOWDESWELL, J. A., SOLHEM, A. & ELVERHOh A. 1992. Seismic architecture and sedimentation in northwest Spitsbergen fjords. Marine Geology, 103, 53-68. SHELL 1995. Geological Data Table, (Version 2-1). Mesozoic and Paleozoic [time scale]. Shell, The Hague). SH~PILOV,E. V. & MOSSUR, A. P. 1990. On anomalous seismic horizons in the Barents Sea sedimentary cover. Geotectonics, 24. & - - 1 9 9 1 . The structure of the sedimentary section at depth in the Arctic region. International Geology Review, 33. SrtKOLa, I. V., PCrIEHNA, T. M., MAZUR, V. B. & AL'TER, S. M. 1980. [New data on the composition and structure of the sedimentary cover, from the Grumant parametric borehole]. In: SEMEVSrOY, D. V. (ed.) Geologiya osadochnogo chekhla arkhipelaga Sval'bard. Sbornik nauchnykh trudov [Geology of the Sedimentary Platform Cover of the Svalbard Archipelago. A Collection of Scientific Papers]. NIIGA, Leningrad, 13-24. SHVaRTS, V. L. 1985. [Lithologic-stratigraphic division of the Raddedalen-I borehole section (Edge~ya, Spitsbergen archipelago)]. In: VERBA, M. L. (ed.) Geologicheskoye stroyeniye Barentsevo-Karskogo shelfa. "Sevmorgeo", Leningrad, 44-58. SIEBERG, A. 1914. Spitzbergens Erdbeben und Tektonik. Gerlands Beitrage zur Geophysik, 13, 114-120. SIEDE, J., D~ESEN, G. W., KNUDSEN, B.-E. & SNARE, T. 1986. Patterns of Cenozoic sedimentation in the Norwegian-Greenland Sea. Marine Geology, 69, 323-352. SIEDLECr,.A, A. 1968. Lithology and sedimentary environment of the Hyrnefjellet beds and the Treskelodden beds (Late Palaeozoic) at Treskelen, Hornsund, Vestspitsbergen. Studia Geologica Polonica, 21, 53-95. - - 1 9 7 0 . Investigations of Permian cherts and associated rocks in southern Spitsbergen. Norsk Polarinstitutt Skrifter, 147. - - 1 9 7 2 . Length-slow chalcedony and relicts of sulphates - evidence of evaporitic environments in the Upper Carboniferous and Permian beds of Bear Island, Svalbard. Journal of Sedimentary Petrology, 42, 812-816. - - 1 9 7 5 . The petrology of some Carboniferous and Permian rocks from Bjornoya, Svalbard. Norsk Polarinstitutt ~lrbok 1973, 53-72. -

-

507

• SIEDLECKI,S. 1967. Some new aspects of the geology of the Varanger Peninsula (Northern Norway). Preliminary report. Norges geologiske undersokelse, 247, 288-306. SIEDLECKI, S. 1960. Culm beds of the S.W. coast of Hornsund, Vestspitsbergen. Preliminary communication. Studia Geologica Polonica, 4, 93-102. - - 1 9 6 4 . Some remarks on the reconnaissance boat trip around Sorkapplandet to Kvalvfigen, Vestspitsbergen. In: BIRKENMAJER,K. (ed.) Geological Results of the Polish 1957-1958 1959 1960 Spitsbergen Expeditions, Part 3. Studia Geologica Polonica, 11, 28-37. - - 1 9 6 4 . Permian succession on Tokross6ya, S6rkapplandet, Vestspitsbergen. In: BIRKENMAJER, K. (ed.) Geological Results of the Polish 1957-1958 1959 1960 Spitsbergen Expeditions, Part 3. Studia Geologica Polonica, 11, 155-167. - - 1 9 7 0 . A helicoprion from the Permian of Spitsbergen. Norsk Polarinstitutt Arbok 1968, 36-54. & TURNAU, E. 1964. Palynological investigations of Culm in the area SW of Hornsund, Vestspitsbergen. In: BIRKENMAJER, K. (ed.) Geological Results of the 1957-1958 1959 1960 Spitsbergen Expeditions, Part 3. Studia Geologica Polonica, 11, 125-138. SIEGERT, M. J. & DOWDESWELL, J. A. 1995. Numerical modelling of the Late Weichselian Svalbard-Barents Sea Ice Sheet. Quaternary Research, 43, 1-13. & - - 1 9 9 6 . Topographic control on the dynamics of the Svalbard-Barents Sea Ice sheet. In: SOLHEIM,A. et al. (eds) Global and Planetary Change, 12, 27-40. SIGGERUD, E. I. 1993. Characteristics of sequence boundaries and flooding surfaces using trace fossils; examples from Eocene Ebro Basin, N.E. Spain and from midCarboniferous Rift Basins on Spitsbergen, Svalbard. British Sedimentological Research Group, 15-17 December 1993, Abstract volume. SIG~ERUD, T. 1962. The iron occurrence at Farmhamna, Vestspitsbergen. Norsk Polarinstitutt Arbok 1960, 86-89. - - 1 9 6 3 . On the marble-beds at Blomstrandhalvoya in Kongsfjorden. Norsk Polarinstitutt Arbok 1962, 44-49. SILBERL1NG, N. J. & TOZER, E. T. 1968. Biostratigraphic correlation of the marine Triassic of North America. Geological Society of America, Special Papers, 110. SIMMERBACH, B. 1917. Die Steinkohlenvorkommen auf Spitzbergen. Z. Prakt. Geol., 25, 154-157 and 167-173. - - 1 9 1 9 . Die Kohlenlager auf Spitzbergen. Braunkohle, 17, 386-388 and 399-402. SIMONSEN, B. T. 1987. The Kapp Duner Formation [and] the Hambergfjellet Formation. In: MORK, A. (ed.) GeologicalExcursion Guide to Bjornoya. IKU, Trondheim. - - 1 9 8 8 . Upper Palaeozoicfusulinids ofBjornoya. I K U Report 23.1252. SIMVSON, J. B. 1961. The Tertiary pollen flora of Mull and Ardnamukrchan (comparison with other European Tertiary floras by I. M. Simpson). Transactions of the Royal Society of Edinburgh, 16, 421-468. SINDBALLE,K. 1927. Report of the Svalbard Commissioner concerning the claims to land in Svalbard. Parts I and IL Copenhagen. SKAUG, M., DONS, C. E., LAURITZEN, ~. & WORSLEY, D. 1982. Lower Permian palaeoaplysinid bioherms and associated sediments from central Spitsbergen. Polar Research, 2, 57-75. SKILBREI, J. R. 1991. Interpretation of depth to the magnetic basement in the north Barents Sea (south of Svalbard). Tectonophysics, 200, 127-142. - - 1 9 9 2 a . Interpretation of the first available gravity map from Svalbard and the adjacent sea areas (75~176 In: Suppl. 25-27 May 1992, Acadia University, Nova Scotia. Geological Association of Canada, Mineralogical Association of Canada, Abstracts with Programs, 17, A102. - - 1 9 9 2 b . Preliminary interpretation of aeromagnetic data from Spitsbergen, Svalbard Archipelago (76~176 implications for structure of the basement. Marine Geology, 106, 53-68. -& LINEN, O. 1992. Interpretation of aeromagnetic and reflection seismic data from the Billefjorden Fault Zone, Svalbard. Geological Society of America, Abstracts with Programs, 24, A83. , FALEIDE, J. L. & MYKLEHURST. Geologic structure of the northwestern Barents Sea from Aeromagnetic images and seismic data (74~176 submitted. SKJELKVA.LE,B.-L., AMUNDSEN,H. E. F., O'REILLY, S., GRIFEEN,W. L. & GJELSVIK,T. 1989. A prilrtitive alkali basaltic stratovolcano and associated eruptive centres, northwestern Spitsbergen: volcanology and tectonic significance. Journal of Volcanology and Geothermal Research, 37, 1-19. SKOLA, J. V., PCELINA,T. M., MAZUR, V. B. & ALTER, S. M. 1980. [New data on the composition and structure of the sedimentary platform cover on the basis of materials from the drilling of a parametric hole at Grumantbyen]. In: SEMEVSrdY, D. V. (ed.) Geologija osadocnogo cechla archipelaga Sval'bard. Sbornik naucnych -

-

-

-

-

-

trudov [Geology of the sedimentary platform cover of the archipelago of Svalbard. Collection of scientific papers]. NIIGA, Leningrad, 13-24 [in Russian]. SLIVKOVA,R. P., IOEFE, G. A., KONAVALOVA,M. W. & FIRER, G. M. 1976. [New zone of Early Permian bioherm facies in the Timan-Pechora province]. Akademii. Nauk. SSSR. Doklady, 226, 101-103. SKOROPISTEVA, L. YE. 1969. Late Paleozoic sea lilies of the Soviet and non-Soviet Arctic. In: Uchenyye Zapiski NIIGA: Paleontologiya i Biostratigrafiya, 25. [Scholarly Papers on Palaeontology and Biostratigraphy]. NIIGA, Leningrad; Gerke, AA, 30-57, SMELROR, M. 1987. Bathonian and Callovian (Middle Jurassic) dinoflagellate cysts and acritarchs from Franz Joseph Land, Soviet Arctic. Polar Research, 5, 221-238. - - 1 9 8 8 . Bathonian to Early Oxfordian dinoflagellate cysts and acritarehs from Kong Karls Land, Svalbard. Review of Palaeobotany and Palynology, 56, 257-304. - - 1 9 8 9 . Chlamydophorella ectotabulata sp.nov, a gonyaulacoid dinoflagellate cyst from the Late Bathonian to the Oxfordian of the Arctic. Review of Paleobotany and Palynology, 61, 131-145. - - 1 9 9 1 . Two new dinoflagellate cysts from the Middle Jurassic of the Barents Shelf region. Journal of Mieropalaeontology, 10, 175-180.

508

REFERENCES

Jurassic stratigraphy of the Western Barents sea region, a review. Geobios M.S., 17, 441-451. -& ARHUS, N. 1989. Emendation of the dinoflagellate cyst genus Crussolia Wolfard and Van Erve 1981, and description of C. dalie n.sp. from the Callovian of Svalbard. Neues Jahrbuch ffir Geologie und Palaontologie, Monatschefte 1989, 37-46. SMIRNOW, L. 1961. Oil basins surround the Arctic Ocean. Worm Oil, 27-32. SMITH, A. G., HURLEY, A. M. & BRIDEN, J. C. 1980. Phanerozoic Palaeocontinental Worm Maps. Cambridge University Press. , SMITI~, D. G. & FUNNELL, B. M. 1994. Atlas of Mesozoic and Cenozoic Coastlines. Cambridge University Press. SMITH, D. G. 1974. Late Triassic pollen and spores from the Kapp Toscana Formation, Hopen, S v a l b a r d - a preliminary account. Review of Palaeobotany and Palynology, 17, 175-178. - - 1 9 7 5 . The stratigraphy of Wilhelmoya and Hellwaldfjellet, Svalbard. Geological Magazine, 112, 481-491. - - 1 9 7 7 . Late Triassic palynology and the definition of the lower boundary of the Rhaetian Standard Age/Stage. Geological Magazine, 114, 153-156. - - 1 9 8 2 . Stratigraphic significance of a palynoflora from ammonoid-bearing Early Norian strata in Svalbard. Newsletter on Stratigraphy, 11, 154-161. - - 1 9 8 6 . Stratigraphic time-correlation in the Late Triassic of Svalbard: a discussion of N.F. Hughes's working methods. Special Papers in Palaeontology, 35, 149-161. - - 1 9 8 7 . Late Paleozoic to Cenozoic reconstructions of the Arctic. In: TAILLEUR,I. & WEIMER, P. (eds) Alaskan North Slope Geology, 2. Society of Economic Paleontologists and Mineralogists/Alaskan Geological Society, 785-795. & PICKTON,C. A. G. 1976. The Helvetiafjellet Formation (Cretaceous) of NorthEast Nordenski61d Land, Spitsbergen. In: HARLAND,W. B. et al. (eds) Some Coalbearing Strata in Svalbard. Norsk Polarinstitutt Skrifter, 164, 47-55. , HARLAND, W. B. & HUGHES, N. F. 1975. Geology of Hopen, Svalbard. Geological Magazine, 112, 1-23. , , -& PICKTON, C. A. G. 1976. The geology of Kong Karls Land, Svalbard. Geological Magazine, 113, 193-232. SMITH, M. P. 1988. Cambrian through Devonian Panarctic tectonic events. In: HARLAND, W. B. & DOWDESWELL,E. K. (eds) Geological Evolution of the Barents Shelf Region. Graham & Trotman, London, 7-17. In press. Ordovician stratigraphy of Bjornoya and North Greenland: Constraints on tectonic models for the Arctic Caledonides and the opening of the Greenland Sea. Journal of the Geological Society, London. & PEEL, J. S. 1986. The age of the Danmarks Fjord Member, eastern North Greenland. Rapport, Gronlands Geologiske Undersogelse, 132, 7-13. --, SONDERHOLM, M. & TULL, S. J. 1989. The Morris Bugt Group (Middle Ordovician-Silurian) of North Greenland and its correlatives. In: North Greenland Stratigraphy and Petroleum Geology. Rapport, Gronlands Geologiske Undersogelse, 143, 5-20. SMULIKOWS~I, W. 1960. Preliminary report on the petrology of the Isjb6rnhamna Formation. Bulletin de l'Acad~mie Polonaise des Sciences. S#rie des Sciences Gdologiques et G~ographiques, 8, 159 162. - - 1 9 6 0 . Evolution of the amphibolite complex of Upper Revdalen. In: Petrologic Supplements to the Geological Guide of Excursion A.16, 21st International Geological Congress. International Geological Congress, Norden, 25-46. - - 1 9 6 0 . Evolution of the amphibolite complex of Upper Revdalen. Bulletin de l'Acaddmie Polonaise des Sciences. S~rie des Sciences Gdologiques et G~ographiques, 8, 85-93. - - 1 9 6 5 . Petrology and some structural data of lowest metamorphic formations of the Hecla Hoek succession in Hornsund, Vestspitsbergen. Studia Geologica Polonica, 21, 97-107. - - 1 9 6 8 . Some petrological and structural observations in the Hecla Hock succession between Werenskioldbreen and Torellbreen, Vestspitsbergen. Studia Geologica Polonica, 21, 97-161. - - 1 9 7 4 . Amphiboles and biotite in relation to the stages of metamorphism in granogabbro. Mineralogical Magazine, 39, 857-866. & KOZLOWSKI, A. 1994. Distribution of cerium, lathanium and yttrium in allanites and associated epidotes of metavolcanic rocks of Hornsund area, Vestspitsbergen. Neues Jahrbuch Mineralogie, Abh, 166, 295-324. SOKOLOV,D. N. 1908. [Aucelles of the Timan and Spitsbergen]. Trudy Geologicheskago Komiteta. Nov. Ser., 36, 1-29 [in Russian with German summary]. - - 1 9 2 2 . Vorl~iufiger Bericht fiber die Bearbeitungsergebnisse des von HOEL im Festungsprofil gesammelten Materials. Travaux du Musde G~ologique (et Mineralogique ) Pierre le Grand pr~s l'Acad~mie Imp~riale des Sciences de St. Petersbourg, 8, 1917-1918. - - 1 9 2 2 . [Report on work carried out in 1914]. Trudy Geologieheskago (I Mineralogicheskago) Muzeya imeni. Petra Velikago lmperatorskoi Akademii Nauk, St. Petersburg, 3, 124-126. BODYLEVSKV,W. 1931. Jura und Kreidefaunen von Spitzbergen. Skrifter om Svalbard og Ishavet, 35, 1-151. SOKOLOV, V. N. 1964. [Geological make-up and oil bearing prospects of the Spitsbergen Archipelago]. In: SOKOLOV, V. N. (ed.) Conference on the Geology of Spitsbergen, Leningrad 1964: Summary of Contributions. NIIGA, Leningrad, 3-6. - - 1 9 6 5 . [A geological sketch of Spitsbergen]. In: SOKOLOV,V. N. (ed.) Materialy po Geologii Shpitsbergena. NIIGA, Leningrad, 8-28. & LIVSHITS,Y. Y. 1966. [The West Spitsbergen graben-forming trough and the history of its formation]. In: Conference on the Problem of Downwarping, 20-23 April 1966, Leningrad. Summaries of Reports. NIIGA, Leningrad, 159-161. & PCHELINA, T. M. 1967. [Lower and Middle Triassic of Sorkapp Land, West Spitsbergen]. Doklady Akademii Nauk SSSR, 176, 1374-1377 [translation in Doklady of the Academy of Sciences USSR, Earth Sciences Sections, 176(1-6), 109-112]. & VASlLEVSKAYA, N. F. (eds) 1972. Mezozoyskiye otlozheniya Sval'barda [Mesozoic" Deposits in Svalbard]. NIIGA, Leningrad.

--1994.

-

-

-

-

-

-

-

-

-

-

-

-

-

-

&

(ed.) 1965. [Materials on the geology of Spitsbergen]. NIIGA, Leningrad. (ed.) 1967. [Materials on the stratigraphy of Spitsbergen]. NIIGA, Leningrad. (ed.) 1976. [Geology of Svalbard. A Collection of Articles]. NIIGA, Leningrad. , KRASIL'SnCmKOV, A. A. & LIVSHITS, Y. Y. 1968. The main features of the tectonic structure of Spitsbergen. Geological Magazine, 105, 95-115. - - ' 0 0--&1 1 0 7 - - 1 9 6 8 . Tectonics of the Spitsbergen Archipelago. Geotectonies, 2, [translation of Geotektonika, 2, 65-82]. , , & SEMEVSKtY, D. V. 1973. Structural history of Spitsbergen and adjoining shelves. In: PITCHER,M. (ed.) Arctic Geology. Memoirs of the American Association of Petroleum Geologists, 19, 269-274. SOLrtEIM, A. 1986. Submarine evidence of glacier surges. Polar Research, 4, n.s., 91-95. -& ANDERSEN, E. S. 1995?. Late Cenozoic seismic stratigraphy and character of the Svalbard-Barents Sea margin. Plates 72-75. In: CRANE, K. & SOLHEIM, A. (eds) Seafloor Atlas of the Norwegian-Greenland Sea. Norsk Polarinstitutt, 155-164. 8s KRISTOFEERSEN,Y. 1984. Distribution of sediments above bedrock and glacial history on the western Barents Sea. Norsk Polarinstitutt Skrifter, 1979b. 8s PFIRMAN, S. L. 1985. Sea-floor morphology outside a grounded, surging glacier; Brfisvellbreen, Svalbard. Marine Geology, 65, 127-143. , ANDERSON, E. S. F. W., ELVERHOI, A. 8s FIEDLER, A. 1996. Late Cenozoic depositional history of the western Svalbard continental shelf, controlled by subsidence and climate. In: SOLHEIM,A. et al. (eds) Global and Planetary Change, 12, 135-148. , ELVERHOI,A., ANDERSEN, E. S. 8s JAHRE, H. 1991. Marine geological/geophysical cruise on the western Svalbard margin 1990: cruise report. Norsk Polarinstitutt, Report Series, 69. SOLHEIM,F. et al. 1996. Impact of glaciations on basin evolution: Data and model from the Norwegian margin and adjacent areas. Global and Planetary Change, 12, (N). STELE, G. 1935. Die devonischen Ostracoden Spitzbergens: I. Leperditiidae. Skrifter om Svalbard og Ishavet, 64, 1-61. SoLLID, J. L. 8s SORBEL, L. 1988. Influence of temperature conditions information of endmoraines in Fennoscandia and Svalbard. Borias, an International Journal of Quaternary Geology, 17, 553-558. -& 1988. [The distribution and pattern of superficial deposits and landforms in Svalbard- some main features]. Norsk Geographisk Tidsskrift, 42, 265-270. , ETZELMI]LLER,B., VATNE, G. 8s DEGARD, R. S. 1994. Glacial dynamics, material transfer and sedimentation of Erikbreen and Hannabreen, Leifdefjorden, northern Spitsbergen. Zeitschriftffir Geomorphologie, 97, 123-144. SoLov'YEV, V. A. 1989. [Stage and zone scales of the Boreal Mesozoic of the USSR]. Trudy IGIG SO AN SSSR, 722, 223. SOLOV'YEVA,M. N. 1969. Foraminifera of the genus Wedekindellina from Spitsbergen. Voprosy Mikropaleontologii, 12, 34-46. SOOT-RYEN, T. 1925. Notes on some Mollusca and Brachiopoda from Spitsbergen. Tromso Museums Aarshberetning, 47. - - 1 9 3 2 . Pelecypods, with a discussion of possible migrations of Arctic pelecypods in Tertiary times. The Norwegian North Polar Expedition with the "Maud" 1918-1925 Scientific Results 5. Bergen. - - 1 9 3 9 . Some pelecypods from Franz Josef Land, Victoriaoya and HopeD, collected on the Norwegian scientific Expedition 1930. Meddelelser. Norges Svalbard-og Ishavs-undersokelsen, 43. SOPER, N. J. 1980. Caledonides of East and North Greenland and Svalbard. Episodes, 19-20. - - 1 9 9 4 . Neoproterozoic sedimentation on the northeast margin of Laurentia and the opening of Iapetus. Geological Magazine, 131,291-299. 8s HIGG1NS, A. K. 1987. A shallow detachment beneath the North Greenland Fold Belt: implications for sedimentation and tectonics. Geological Magazine, 124, 441-450. & - - 1 9 9 0 . Models for the Ellesmerian mountain front in North Greenland: a basin margin inverted by basement uplift. Journal of Structural Geology, 12, 83-97. & - - 1 9 9 1 . Devonian-Early Carboniferous deformation and metamorphism, North Greenland. In: TRETTIN, H. P. (ed.) Geology of the Innuitian Orogen and Arctic Platform of Canada and Greenland. Decade of North American Geology, E. Geological Society of America and Geological Survey of Canada, 3, 283-291. , DAWES, P. R. & HIGGINS, A. K. 1982. Cretaceous-Tertiary magmatic and tectonic events in North Greenland and the history of adjacent ocean basins. Meddeleser om Gronland, Geoscience, 8, 205-219, , STRACHAN, R. A., HOLDSWORTH,R. E., GAYER, R. A. 8s GREILING,R. O. 1992. Sinistral transpression and the Silurian closure of Iapetus. Journal of the Geological Society, London, 149, 871-880. SOSIPATROVA,G. P. 1967. [Foraminifers of the Upper Palaeozoic]. In: SOIr V. N. (eds) Materialy po stratigrafii Shpitsbergena. NIIGA, Leningrad, 94-119. --1967. [Upper Paleozoic foraminifera assemblages of Spitsbergen]. Doklady Akademii Nauk SSSR, 176, 182-185 [translation in Doklady of the Academy of Sciences USSR, Earth Sciences Sections, 176(1-6), 45-47]. --1969. [Foraminifera from the Kapp Starostin Formation of Spitsbergen]. In: GERKE, A. A. (ed.) Uchenyye Zapiski NIIGA: Paleontologiya i Biostratigrafiya [Scholarly Papers on Palaeontology and Biostratigraphy], 27, 46-79. SPALL, H. 1968. Anomalous palaeomagnetic poles from Late Mesozoic dolerites from Spitsbergen. Earth and Planetary Science Letters, 4, 73-78. SPATH, L. F. 1921. On ammonites from Spitsbergen. Geological Magazine, 58, 297-305 and 347-356. SPENCER, A. M. 1971. Late Pre-Cambrian glaciation in Scotland. Geological Society, London, Memoirs, 6. -(ed.) 1984. Petroleum Geology of the North European Margin. NPF/Graham & Trotman, London.

----

-

-

-

-

1

-

-

-

-

-

-

9

8

0

,

REFERENCES --,

HOME, P. C. & BERGLUND, L. T. 1984. Tertiary structural development of the western Barents Shelf: Troms to Svalbard. In: SPENCER, A. M. et al. (eds) Petroleum Geology of the North European Margin. Graham & Trotman, London, 199~09. SPICER, R. A. t~ PARRISH, J. T. 1986. Paleobotanical evidence for cool north polar climates in Middle Cretaceous (Albian-Cenomanian) time. Geology, 14, 703-706. SPJELDNJES, N. 1961. Ordovician climatic zones. Norsk Geologisk Tidskrift, 41, 45-77. - - 1 9 6 4 . The Eocambrian glaciation in Norway. Geologische Rundschau, 54, 24-45. - - 1 9 8 2 . Palaeoecology of Ichthyostega and the origin of the terrestrial vertebrates. In: GALLITELLI, E. M. (ed.) Proceedings of the 1st International Meeting on Palaeontology, Essential of Historical Geology. Venice, 323-343. SRIVASTAVA, S. P. 1978. Evolution of the Labrador Sea and its bearing on the early evolution of the North Atlantic. Geophysical Journal of the Royal Astronomical Society, 52, 313-357. - - 1 9 8 5 . Evolution of the Eurasian Basin and its implications for the movement along the Nares Strait. Tectonophysics, 114, 29-53. & ROEST, W. R. 1989. Sea floor spreading history II-VI. In: BELL, J. S. (Co-ordinator) East-coast Basin Atlas Series, Labrador Sea. Geological Survey of Canada, Atlas Geosciences Centre, sheet L17.2 sheet L17.6. t~ TAPSCOTT,C. R. 1986. Plate kinematics of the North Atlantic. In: VOGT, P. R. & TUCHOLKE, B. E. (eds) The Western North Atlantic Region. Geology of North America, M, Geological Society of America, 379 404. SRODON, A. 1968. A survey of botanical and palaeobotanical research of the Polish Spitsbergen expeditions 1957-1960. In: BIRKENMAJER,K. (ed.) Polish Spitsbergen Expeditions 1957-1960. Polish Academy of Sciences, Warrzawa, 91~5. STAFF, H. & WEDEKIND, R. 1910. Der oberkarbone Foraminiferensapropelit Spitzbergens. Bulletin of the Geological Institution of the University of Uppsala, 10, 81-123. STANLEY, W. D., LABSON, V. F., NOKLEBERG,W. J., CSEJTEY, B., JR. & FISHER, M. A. 1990. The Denali Fault system and Alaska Range of Alaska: evidence for underplating Mesozoic flysch from magnetotelluric surveys. Geological Society of America, Bulletin, 102, 160-173. STATISTISKE CENTRALBYRA (ed.) 1916. [Mining in Svalbard. Reports in Norges Bergverksdr(ft since 1916]. Oslo. STEEL, R. J. 1977. Observations on some Cretaceous and Tertiary Sandstone bodies in Nordenski61d Land, Svalbard. Norsk Polarinstitutt flrbok 1976, 43-67. - - 1 9 9 2 . The Tertiary succession of the Central Basin: sequence stratigraphy and its tectonic implications (abstract). Norsk Geologisk Tidsskrift, 72, 138. & WORSLEY, D. 1984. Svalbard's post-Caledonian strata: an atlas of sedimentational patterns and palaeogeographic evolution. In: SPENCER, A. M. et al. (eds) Petroleum Geology of the North European Margin. Norwegian Petroleum Society/Graham & Trotman, London, 109-135. , DALLAND, A., KALGRAFF, K. & LARSEN, V. 1979. An outline of the history of sedimentation of Svalbard's central Tertiary basin. In: Norwegian Sea Symposium (NSS/24), Norwegian Petroleum Society, Tromso, 1-29. , , & 1981. The Central Tertiary Basin of Spitsbergen: sedimentary development of a sheared-margin basin. In: KERR, J. W., FERGUSSON, A. J. & MACHAN, L. C. (eds) Geology of the North Atlantic Borderlands. Memoirs of the Canadian Society of Petroleum Geologists, 7, 647--664. , GJELBERG, J. & HAARR, G. 1978. Helvetiafjellet Formation (Barremian) at Festningen, Spitsbergen - a field guide. Norsk Polarinstitutt ,4rbok 1977, 111-128. , HELLAND-HANSEN,W., KLEINSPEHN,K., NOTTVEDT,A. & RYE-LARSEN,M. 1985. The Tertiary strike-slip basins and orogenic belt of Spitsbergen. In: BmDLE, K. T. & CHRIST~E-BLICK,N. (eds) Strike-slip Deformation, Basin Formation, and Sedimentation. Special Publications, Society of Economic Paleontologists and Mineralogists, 37, 339 359. , WINSNES,T. S, & SVALVIGSEN,O. 1989. Description of Geological Map of Svalbard. 1:100.000. Sheet ClOG Braganzavdgen. Norsk Polarinstitutt Temakart, 4. STEMMERIK, L. 1988. Discussion. Brachiopod zonation and age of the Permian Kapp Starostin Formation (central Spitsbergen). Polar Research, 6, 179-180. - - 1 9 9 2 / 3 . Moscovian bryozoan-dominated build-ups, northern Amdrup Land, eastern North Greenland. In: VORREN, T. O. (ed.) Arctic Geology and Petroleum Potential. Elsevier, Amsterdam, 99-106. & LARSSEN, G. B. 1993. Diagenesis and porosity evolution of Lower Permian Paleoaplysina buildup, Bjornoya, Barents sea: An example of diagenetic response to high frequency sea level fluctuations in an arid climate. In: HORBURY, A. D. & ROBINSON,A. G. (eds) Diagenesis and basin development. American Association of Petroleum Geologists, studies in Geology, 36, 199-211. -& PIASECKI, S. 1991. The Upper Permian of East Greenland a review. -

-

-

-

-

-

Zentralblalt ffim Geologie und Paleontolgie, 1,825-837. & WORSLEY, D. 1989. Late Palaeozoic sequence correlations, North Greenland, Svalbard and the Barents Shelf. In: COLLINSON, J. D. (ed.) Correlation in Hydrocarbon Exploration. Graham & Trotman, London, 99-111. -& - - 1 9 9 5 . Permian history of the Barents Shelf area. In: SCHOLLE,P.A. et al. (eds) The Permian of Northern Pangea 2. Sedimentary Basins and environments, Springer-Verlag, 82-97. , LARSON,P. A., LARSSEN, G. B., MURK, A. & SIMONSEN,B. T. 1994. Depositional evolution of Lower Permian Palaeoaplysina build-ups, Kapp Dunrr Formation, Bjornoya, Arctic Norway. Sedimentary Geology, 92, 161-174. STENSI0, E. A. 1918. Zur Kenntnis des Devons und des Kulms an der Klaas Billenbay, Spitzbergen. Bulletin of the Geological Institution of the University of Uppsala, 16, 65-80. - - 1 9 1 8 . Notes on a Crossopterygian fish from the Upper Devonian of Spitsbergen. Bulletin of the Geological Institution of the University of Uppsala, 16, 115-124. - - 1 9 1 8 . Notes on some fish remains collected at Hornsund by the Norwegian Spitsbergen Expedition 1917. Norsk Geologisk Tidsskrift, 5, 75-78.

-

-

509

- - 1 9 2 1 . Triassic FishesJ~om Spitsbergen, Part L Adolf Holzhansen, Vienna. - - 1 9 2 5 . Triassic Fishes from Spitzbergen, Part II. Kungliga Svenska Vetenskapsakademiens Handlingar, 2, Stockholm. - - 1 9 2 7 . The Downtonian and Devonian vertebrates of Spitsbergen. Part I. Family Cephalaspidae. Skrifter om Svalbard og Ishavet, 12, 1-391. STEPANOV, D. L. 1924. [Short article on the bryozoan fauna of Bear Island]. Izvestiya Geologicheskogo Komiteta, 40. - - 1 9 3 6 . [Contribution to the knowledge of the brachiopoda of the Upper Paleozoic of Spitsbergen]. Uchenyye Zapiski Leningradskogo Gosudarstvennogo Universiteta, 9, 114-123. - - 1 9 3 7 . [Permian Brachipoda of Spitsbergen]. Trudy Arkticheskogo Instituta, 76, 105-192. - - 1 9 5 7 . [A new stage of the Permian system in the Arctic]. Vestnik Leningradskogo Gosudarstvennogo Universiteta, 24, 20-24. STEVENSON, J. J. 1905. Recent geology of Spitzbergen. Journal of Geology, 13, 611-616. - - 1 9 0 5 . The Jurassic coal of Spitzbergen. Annals of the New York Academy of Sciences, 16, 82 95. STEWART, D. J., BERGE, K. & BOWLIN1995. Exploration trends in the southern Barents Sea. In: HANSLIEN,S. (ed.). NPF Special Publication, 4. Elsevier, Amsterdam. STOLLEY,E. 1911. Zur Kenntnis der arktischen Trias. Neues Jahrbuchfuer Mineralogie, Geologic und Paldeontologie 1911, 1, 115-125. - - 1 9 1 2 . Ober die Kreideformation und ihre Fossilien auf Spitzbergen. Kungliga Svenska Vetenskapsakademiens Handlingar, 47. Stockholm. STORETVEDT,K. M. 1972. Old Red Sandstone palaeomagnetism of central Spitsbergen and the Upper Devonian (Svalbardian) phase of deformation. Norsk Polarinstitutt ,4rbok 1970, 59-69. STORMER, L. 1934. Downtonian Merostomata from Spitsbergen, with remarks on the sub-order Synziphosura. Skrifter udgivne af Videnskabsselskabet i Kristiania. Mat.-Naturv, 3, 1~6. STRACHAN, R. A. 1994. Evidence in North-East Greenland for Late Silurian - Early Devonian regional extension during the Caledonian orogeny. Geology, 22, 913~16. , NUTMAN, A. P. & FRIDERICHSEN 1995. Shrimp U-Pb geochronology and metamorphic history of the Smallefjord sequence, N.E. Greenland Caledonides. Journal of the Geological Society, London, 152, 779-784. STROMBERG,B. 1972. Glacial striae in southern Hinlopenstretet and Kong Karls Land, Svalbard. Geographiske Annalesas, 54A, 53-65. STUPAVSKY,M., SYMONS,D. T. A. 8z GRAVENOR,C. P. 1982. Evidence of metamorphic remaglaetisation of Upper Precambrian tillite in the Dalradian Supergroup of Scotland. Transactions of the Royal Society of Edinburgh, 73, 59-65. STURT, B. A., PRINGLE, I. R. 8z RAMSAY, D. M. 1978. The Finnmarkian phase of the Caledonian Orogeny. Journal of the Geological Society, London, 135, 597-610. , SOPER, N. J., BRUCK, P. M. 8z DUNNING, F. W. 1980. Caledonian Europe. Episodes, 1980, 13-21. SUESS, E. 1888. Das Antlitz der Erde [The Face of the Earth], 2. Oxford [translation by H. B. C. Sollas 1905]. SUMMERHAYES, V. S. t~ ELTON, C. S. 1928. Further contributions to the ecology of Spitsbergen. Journal of Ecology, 16, 193~68. SUNDVOR, E. • ELDHOLM, O. 1976. Marine Geophysical Survey on the Continental Margin from Bear Island to Hornsund, Spitsbergen. University of Bergen, Seismological Observatory, Scientific Report, 3. -& 1979. The western and northern margin off Svalbard. Tectonophysics, 59, 239-250. , CRANE, K., VOGT, P., CHAYES, D., JONES, C., NISHIMURA,C., DEMOUSTIER,C., DOSS, H., SHOR, A., ROGNSTAD, M., ERICKSON, J., DANG, S., SENDER, J. t~; YAMADA, G. 1990. SeaMARCII and associated geophysical investigation ,of the Knipovich Ridge, Molloy Ridge/Fracture Zone, and Barents/Spitsbergen continental margin. Part I: Overview (abstract). LOS (Transactions of the American Geophysical Union), 71, 622. , ELDHOLM, O., GIDSKEHAUG, A. & MYHRE, A. M. 1977. Marine geophysical survey on the western and northern continental margin off" Svalbard. Scientific Reports of the University of Bergen Seismological Observatory, 4. , GIDSKEUAUG,A., MYHRE, A. & ELDHOLM, O. 1978. Marine Geophysical Survey on the Northern Svalbard Margin. University of Bergen, Seismological Observatory, Scientific Reports, 5. , JOHNSON,G. L. & MYHRE, A. 1982. Some Aspects of Morphology and Structure of the Yermak Plateau, NW of Spitsbergen. University of Bergen Seismological Observatory, NPD Scientific Report, 8. - - - , MYHRE, A. M., AUSTEGARD,A., HAUGLAND,K., ELDHOLM,O. & GIDSKEHAUG,A. 1982. Marine geophysical survey on the Yermak Plateau. Scientific Reports of the University of Bergen Seismological Observatory, 7. 8~;ELDHOLM,O. 1979. The Svalbard continental margin. In: Norwegian Sea Symposium (NSS/6). Norwegian Petroleum Society, 1-25. , SELLEVOLL, M., GIDSKEHAUG, A. et al. 1978. Seismic investigations on the western and northern margin of Svalbard. Polarforschung, 48, 41-43. SURLYK, F. & ZAKHAROV,V. A. 1982. Buchiid bivalves from the Upper Jurassic and Lower Cretaceous of East Greenland. Palaeontology, 25, 727-753. SVENDSEN, J. I., MANGERUD,J., ELVERH~I,A., SOLHEIM,A. & SCHUTTENHELM,R. T. E. 1992. The Late Weichselian glacial minimum on western Spitsbergen inferred from offshore sediment cores. Marine Geology, 104, 1-17. -& MILLER, G. H. 1989. Denudation rates in the Arctic estimated from lake sediments on Spitsbergen, Svalbard. Palaeogeography, Palaeoclimatology, Palaeoecology, 76, 153-168. SVENSSON, H. 1970. Pingos i yttre delen av Adventdalen. Norsk Polarinstitutt l~rbok 1970, 168-174. SVENSSON, T. 1931. Svenska Spetsbergsexpeditionen 1930. Ymer, 51, 77 84. ,

-

-

,

-

-

510

REFERENCES

SVERDRUP, E. & BJORLYKKE,K. 1992. Small faults in sandstones from Spitsbergen and Haltenbanken. A study of diagenetic and deformational structures and their relation to fluid fow. In: LARSEN,R. M. et al. (eds) Structuraland Tectonic Modeling and its Application to Petroleum Geology. Norwegian Petroleum Society (NPF), Special Publication, 1. Proceedings of Norwegian Petroleum Society Workshop, October 1989, Stavanger, Norway, Amsterdam, Elsevier, 507-517. & PRESTHOLM, E. 1990. Synsedimentary deformation structures and their implications for stylolitization during deeper burial. Sedimentary Geology, 68, 201-210. SVESHNIKOVA, I. N. & BUDANTSEV, L. YU. 1969. [Paleozoic and Mesozoic floras of Western Spitsbergen, Franz Josef Land and the New Siberian Islands], 1 [Fossil Floras of the Arctic]. V. L. Komarov Botanical Institute, Akademii Nauk, SSSR. SVEUM, T., REYMERT, P. K. • HAUAN, M. A. 1987. [Svalbard Literature: a bibliography]. Universitetsbiblioteket i Troms, Troms Museum. SWEENY, F. J., WEBER, J. R. & BLASCO, S. M. 1982. Continental ridges in the Arctic Ocean: LOREX constraints. Tectonophysics, 89, 217-238. SWETT, K. 1981. Cambro-Ordovician strata in Ny Friesland, Spitsbergen, and their palaeotectonic significance. Geological Magazine, 118, 225-250. -& CROWDER, R. K. 1982. Primary phosphatic oolites from the Lower Cambrian of Spitsbergen. Journal of Sedimentary Petrology, 52, 587-593. & KNOLL, A. H. 1985. Stromatolitic bioherms and microphytolites from the Late Proterozoic Draken Conglomerate Formation, Spitsbergen. Precambrian Research, 28, 327-347. & 1989. Marine pisolites from Upper Proterozoic carbonates of East Greenland and Spitsbergen. Sedimentology, 36, 75-93. , HAMBREY, M. J. & JOHNSON, D. B. 1978. Lobate rock glaciers and related talus terraces in northern Spitsbergen. American Association of Petroleum Geologists, Abstracts with Programs, 10. -& 1980. Rock glaciers in northern Spitsbergen. Journal of Geology, 88, ~175-482. SYKES, L. R. 1965. The seismicity of the Arctic. Bulletin of the Seismological Society of America, 55, 501-518. SYKES, R. M. & CALLOMON, J. H. 1979. The Amoeboceras Zonation of the Boreal Upper Oxfordian. Palaeontology, 22, 839-903. & SURLYK,F. 1976. A revised ammonite zonation of the Boreal Oxfordian and its application in northeast Greenland. Lethaia, 9, 421-436. SZANIAWSKI, H. & MALKOWSKI, K. 1979. Conodonts from the Kapp Starostin Formation (Permian) of Spitsbergen. Acta Palaeontologica Polonica, 24, 231-264. SZCZESNV,R. 1988. [Tectonics of Hilmarfjellet/Spitsbergen]. In: JAHN,A., PEREYMA,J. & SZCZEPANKIEWICZ-SZMYRKA,A. (eds) .~V Sympozjum Polarne. Stan obecny i wybrane problemy polskich badan polarnych, Wroclaw 19-21 May 1988. Wydawnictwo Uniwersytetu Wroclawskiego, Warsaw, 8-1 I. SZUPRYCZYNSKI,J. 1968. Glaciations in the Spitsbergen area. Geogr. Pol., 14, 175-183. TALIMAA, V. N. 1978. ]Silurian and Devonian Thecodontes of the U.S.S.R and Spitsbergen]. Mokslas, Vil'nius. TALWANI, M. & ELDHOLM, O. 1977. Evolution of the Norwegian-Greenland Sea. Bulletin of the Geological Society of America, 88, 969-999. , MUTTER, J. & ELDHOLM,O. 1981. The initiation of the opening of the Norwegian Sea. In: Geology of Continental Margins. Oceanologica Acta, 4, 23-30. TAPPONIER, P., PELTZER, G., LE DAIN, A. Y., ARMIJO, R. & COBBOLD, P. 1982. Propagating extrusion tectonics in Asia: new insights from simple experiments with plasticine. Geology, 10, 611-616. TARUSSOV, A. 1992. The Arctic from Svalbard to Severnaya Zemlya: climatic reconstructions from ice cores. In: BRADLEY, R. S. t~ JONES, P. D. (eds) Climate since A.D. 1500. Routledge, London, 505-516. TAYLOR, F. B. 1928. Sliding continents and tidal forces. In: Theory of Continental Drift: 1 8 - 2 0

-

-

-

-

-

-

a symposium on the origin and movement of land masses both intercontinental and intra-continental as proposed by Alfred Wegener. American Association of Petroleum Geologists, 158 177. TAYLOR, P. N., KALSBEEK, F. & BRIDGWATER, D. 1992. Discrepancies between neodymium, lead and strontium model ages from the Precambrian of southern East Greenland: evidence for a Proterozoic granulite-facies event affecting Archean gneisses. Chemical Geology, 94, 284 291. TEBEN'KOV,A. M. 1983. [Late Precambrian magmatic formations of Nordaustlandet]. In: KRASIL'SHCHIKOV,A. A. & BASOV,V. A. (eds) Geologiya Shpitsbergena: sbornik nauchnykh trudov [The Geology of Spitsbergen." a Collection of Papers]. "Sevmorgeo", Leningrad, 74-86. -& KORAGO,YE. A. 1992. [Listvanites of West Spitsbergen]. Zapiski Vsesoyuznogo Mineralogicheskogo Obshchestva, 2, 69-84. -& SmoTK~rq,A. N. 1990. A new occurrence of Cenozoic(?) basalt from Manbreen, Ny Friesland, northeastern Spitsbergen. Polar Research, 8, 295 298. --, BALASHOV, YU. A. & KRASIL'Sr~CmKOV,A. A. 1991. Trace of pre-Paleozoic events in Svalbard (abstract). In: Terranes in the Arctic Caledonides, Tromso, 12-16 August 1991. Terra Abstracts, 4, 32. - - , BUROV, Yu. P. & VANSIqTEYN,B. G. 1980. [The geochemistry of some elements of Mesozoic dolerites of the Svalbard Archipelago]. In: SEMEVSmu D. V. (ed.) Geologiya osadochnogo chekhla arkhipelaga Sval'bard. Sbornik nauchnykh trudov [Geology of the Sedimentary Mantle of the Svalbard Archipelago. A Collection of Scientific Papers]. NIIGA, Leningrad, 121-128. --, OHTA, Y., BALASHOV,J. A. & SmOTKIN, A. N. 1996. Newtontoppen granitoid rocks; their geology, chemistry and Rb-Sr age. Polar Research, 15, 67-80. TEYSSIER, C., KLEINSPEHN, K. & PERSHING, J. 1995. Analysis of fault populations partitioning along transform margins. Geological Society of America Bulletin, 107, 68-82. --, TIKOEF, B. & MARKLEu M. 1995. Oblique plate motion and continental tectonics. Geology, 23, 447-451.

THANNHEISER,D. & MOLLER, I. 1994. Frostbodenformen in inneren Woodfjord, NW Spitsbergen. Zeitsehrift ffir Geomorphologie, 97, 195-204. THIED~6, F. 1988. Post-Caledonian thrust structures on Blomstrandhalvoya, Kongsfjorden, NW Spitsbergen. ln: DALLMAN,W. K., ORTA, Y. & ANDERSON,A. (eds) Tertiary Tectonics ofSvalbard. Norsk Polarinstitutt, Report Series, 46, 15-16. & MArqBY, G. M. 1992. Origins and deformation of post-Caledonian sediments on Blomstrandhalvoya and Lovrnoyane, northwest Spitsbergen. In: DALLMANN, W. K., ANDRESEN, A. & KRtLL, A. (eds) Post-Caledonian Tectonic Evolution of Svalbard. Norsk Geologisk Tidsskrift, 72, 27-33. , PICKTON,C. A. G., LEHMANN,U., HARLAND,W. B. & ANDERSON,H. J. 1980. Das Terti/ir von Renardodden (Ostlich Kapp Lyell, West Spitzbergen). Mitteilungen aus dem Geologisch-Paldontologischen lnstitut der Universitdt Hamburg, 49, 135-146. THOMPSON, H. R. 1953. Geology and geomorphology in southern Nordaustlandet (North-East Land), Spitsbergen. Proceedings of the Geologists' Association, 64, 293-312. THOMSON, J. 1871. On the occurrence of pebbles and boulders of granite in schistose rocks in Islay, Scotland. In: 40th Meeting of the British Association. Liverpool

-

-

Transactions: British Association,

8 8 .

THOREN, R. 1969. Picture Atlas of the Arctic. Elsevier, London. THRONOSEN, T. 1979. Kerogen maturation of Triassic deposits in Svalbard. In: Norwegian Sea Symposium (NSS/28). Norwegian Petroleum Society, Tromso, 1-14. - - t 982. Vitrinite reflectance studies of coals and dispersed organic matter in Tertiary deposits in the Adventdalen area, Svalbard. Polar Research, 2, 77-91. THUSU, B. 1978. Aptian to Toarcian dinoflagellate cysts in Arctic Norway. In: THUSU,B. (ed.) Distribution of Biostratigraphically Diagnostic Dinoflagellate Cysts and Miospores from the Northwest European Continental Shell"and Adjacent Areas. IKU, Publications, 100, 61-96. TIDTEN, G. 1972. Morphogenetisch-Ontogenetische Untersuchungen an Pterocorallia aus dem Permo-Karbon yon Spitzbergen [Morphogenetic-ontogenetic study of Pterocorallia from the Permo-Carboniferous of Spitsbergen]. Palaeontographica, A139, 1-63. T6RNEBOHM, A. E. 1875. [Microscopical studies of rocks. 4. Some basic eruptives from Spitsbergen]. Geologiska Ffreningens Stockholm Fdrhandlingar, 2, 543-549. TORSV~K,T. H. 1995 Large continental rotations during Vendian and Palaeozoic times: a simple geodynamic explanation. Norges geologiske undersokelse, Bulletin, 427, 2224. -& TRENCH, A. 1991. The Lower-Middle Ordovician palaeofield of Scandinavia: southern Sweden 'revisited'. Physics of the Earth and Planetary Interiors, 65, 283 291. , LOHMANN,K. C. & STURT, B. A. 1995. Vendian glaciations and their relation to the dispersal of Rodinia: paleomagnetic constraints. Geology, 23, 727-730. , LOVLIE, R. & STURT, B. A. 1985. Palaeomagnetic argument for a stationary Spitsbergen relative to the British Isles (Western Europe) since late Devonian and its bearing on North Atlantic reconstruction. Earth and Planetary Science Letters, 75, 278-288. , RYAN, P. D., TRENCH, A. & HARPER, D. A. T. 1991. Cambrian-Ordovician paleogeography of Baltica. Geology, 19, 7-10. , SMETHURST,M. A., MEERT, J. G., VANDER VOO, R., MCKERROW,W. S., BRASIER, M. D., STURT, B. A. & WALDERHAU6 1996. Continental break-up and collision in the Neoproterozoic and Paleozoic- A tale of Baltica and Laurentia. Earth Science Reviews, 40, 229-258. , VAN DER VOO, R., TRENCH, A., ABRAHAMSEN,N. & HALVORSEN,E. 1992. altica. A synopsis of Vendian-Permian paleomagnetic data and their paleotectonic implications. Earth Science Reviews, 33, 133-152. TOULA, F. 1873. Kohlenkalk-Fossilien yon der Siidspitze yon Spitzbergen. S. B. Akad. Wiss., 68, 267-291. - - 1 8 7 5 . Kohlenkalk- und Zechstein-Fossilien aus dem Hornsund an der SiidWestkfiste von Spitzbergen. S. B. Akad. Wiss., 70, 133-156. - - 1 8 7 5 . Permo-Carbon-Fossilien vonder Westkfiste yon Spitzbergen (Belsund, Cap Staratschin, Nordfjord). Neues Jahrbuch ffir Mineralogie, Geologie and Paldontologie 1875, 225-264. TOWNSEND, C. 1992. Cenozoic tectonics, deformation and basin development on Svalbard (abstract). Norsk Geologisk Tidsskrift, 72, 138-139. -& GAYER, R. A. 1989. The timing of orogenesis in northern Norway: did the Finnmarkian Orogeny occur? In: GAYER, R. A. (ed.) The Caledonian Geology of Scandinavia. Graham & Trotman, London, 63-65. & MANN, A. 1989. The Tertiary orogenic belt of West Spitsbergen: seismic expressions of the offshore sedimentary basins. A comment. Norsk Geologisk Tidsskrift, 69, 135 136. TOZER, E. T. 1967. A standard for Triassic time. Geological Survey of Canada Bulletin, 156, 1 103. - - 1 9 7 3 . Lower and Middle Triassic ammonoids and bivalves from Nordaustlandet (Spitsbergen) collected by Dr. Oscar Kulling in 1931. Geologiska Fdreningens Stockholm Fffrhandlingar, 95, 99-104. - - 1 9 8 8 . Towards a definition of the Permian-Triassic boundary. Episodes, 11, 251-255. & PARKER, J. R. 1968. Notes on the Triassic biostratigraphy of Svalbard. Geological Magazine, 105, 526-542. TRAMMER, J. 1978. Middle Triassic (Ladinian) conodonts and cephalopod arm hooks from Hornsund, Spitsbergen. Acta Geologica Polonica, 28, 283-287. TRETT~N, H. P. 1987. Pearya: a composite terrane with Caledonian affinities in northern Ellesmere Island. Canadian Journal of Earth Sciences, 24, 224-245. --1991. Summary (Silurian-Early Carboniferous deformational phases and associated metamorphism and plutonism, Arctic Islands. In: TREXTIN, H. P. (ed.) Geological of the Innuitian Orogen and Arctic Platform of Canada and Greenland. The Geology of North America, E. Geological Survey of Canada and Geological Society of America. -

-

-

-

REFERENCES , PARRISH, R. R. & RODDICK, J. C. 1992. New U-Pb and 40Ar-30Ar age determinations from northern Ellesmere and Axel Heiberg islands, Northwest Territories and their tectonic significance. Geological Survey of Canada Papers, 92-2, 3-30. TROITSKIY, L. S., PUNNING, J. M., HURT, G. & RAJAMAE, R. 1979. Pleistocene glaciation chronology of Spitsbergen. Boreas, 8, 401-407. , ZINGER, Y. M. & KORYAKIN,et al. 1975. The glaciation of Spitsbergen. Nauka press, Moscow. TSCHERNYSCHEW,F. N. 1898. Lrber die Artinsk-und Karbon-Schwamme vom Ural und vom Timan. Memoires de la Soci~tk russes du Mineralogue, 36, 1-54. - - 1 9 0 2 . Die obercarbonischeu Brachyopoden des Ural und des Timan. Memoires du Comitd Geologique, St. Petersburg, 16, 1-749. TUCHSCHMID, M. & SPILLMANN, P. 1992. Neogene and Quaternary volcanism on Spitsbergen - the revival of an Arctic hot spot. Schweizerische Mineralogische und Petrographische Mitteilungen, 72, 251-270. TUCKER, R. D. & McKERROW, W. S. 1995. Early Paleozoic chronology: a review in light of new U-Pb zircon ages from Newfoundland and Britian. Canadian Journal of Earth Sciences, 32, 368-379. TURCHENKO, S. I. 1987. [The pre-Caledonian stage of tectonic development of the Spitsbergen archipelago as basement to the ancient platform, ln: [Tectonic and Oil-bearing Perspectives of the Basement in the Ancient Platform]. Nauka, Leningrad, 222-230. --, BARKHATOV,D. B., BARMATENKOV,I. I. & SERGEYEV, D. V. 1983. [Geological structure of the west coast of Nordenskirld Land]. In: KRASIL'SHCHIKOV,A. A. ~; BASOV, V. A. (eds) Geologiya Shpitsbergena: sbornik Nauchnykh trudov [Geology of Spitsbergen: a Collection of Scientific Papers]. "Sevmorgeo", Leningrad, 1-15. - - , TEBEN'KOV,A. M., BARKHATOV,D. B. & BARMATENKOV,I. I. 1983. [Geological structure and magmatism of the region of Chamberlindalen, West Spitsbergen]. In: KRASlL'SHCHIKOV,A. A. & BASOV,V. A. (eds) Geologiya Shpitsbergena: sbornik

Nauchnykh trudov [Geology of Spitsbergen: a Collection of Scientific Papers]. "Sevmorgeo", Leningrad, 38-48. --, BARHATOV, D. B., SERGEEV, n . B. & BARMATENKOV, I. I. 1996. Ore mineralization on Spitsbergen and Bjornoya. In: KRASIL'SHCH1KOV,A. A. (ed.) Soviet Geological Research in Svalbard 1962-1992. Norsk Polarinstitutt Meddelelser, 139, 94. , - - - , BUTOMO, N. 1. & BARMATENKOV, t. I. 1996. Geology and mineral occurrences of Spitsbergen. In: KRASIL'SHCHIKOV,A. A. (ed.) Soviet Geological Research in Svalbard 1962-1992. Norsk Polarinstitutt Meddelelser, 139, 95. TYRRELL, G. W. 1922. The pre-Devonian basement complex of central Spitsbergen. Transactions of the Royal Society of Edinburgh, 53, 209-229. - - 1 9 2 2 . The glaciers of Spitsbergen. Transactions of the Geological Society of Glasgow, 17, 1-48. - - 1 9 2 4 . The geology of Prince Charles Foreland, Spitsbergen. Transactions of the Royal Society of Edinburgh, 3, 443-478. - - 1 9 3 3 . Stratigraphical observations in the Stor Fjord region of Spitsbergen. Appendix by J. Weir: Mesozoic fossils from Spitsbergen collected by Dr. G. W. Tyrrell. Transactions of the Royal Society of Edinburgh, 57, 675-697. -& SANDFORD, K. S. 1933. Geology and petrology of the dolerites of Spitsbergen. Proceedings of the Royal Society of Edinburgh, 53, 284-321. UEMISHEK,G. 1985. Geology and Petroleum Resources of the Barents-Kara Shelf in Light of New Geologic Data. Argonne National Laboratory, Reports, ANL/ES-148. UNRU~, R. 1996. The assembly of Gondwanatand (International Geological Congress, Project 288) Gondwanaland sutures and mobile belts. Episodes, 19, 11-20. - - 1 9 9 7 . Rodvinia to Gondwana: the geodynamic map of Gondwana supercontinent assembly. GSA Today, 7, 1-6. USTRITSKIY, V. I. 1962. [New data on the Permian brachiopods of Spitsbergen]. Sbornik statey po paleontologii i biostratigrafii [A Collection of Articles on Palaeontology and Biostratigraphy], 28, NIIGA; Leningrad, 74-89, - - 1 9 6 7 . [Main features of the stratigraphy and palaeogeography of the Upper Palaeozoic of Spitsbergen]. In: SOKOEOV, V. N. (ed.) Materialy po stratigrafii Shpitsbergena. NIIGA, Leningrad, 71-93. - - 1 9 7 1 . [The Carboniferous and Permian deposits of Spitsbergen]. In: [The Biostratigraphy of the Upper Palaeozoic of the Arctic]. Trudy Arkticheskogo Nauchno-Issledovatel'skogo Instituta, 164, 46-50. - - 1 9 7 9 . [On the distribution of brachiopods in Upper Permian deposits of Spitsbergen]. In: SHUE'GINA,N. I. (ed.) Verkhniy paleozoy i mezozoy ostrovov i poberezh'ya arkicheskikh morey SSSR [The Upper Paleozoie and Mesozoic of the islands and coasts of the Arctic seas of the USSR]. NIIGA, Leningrad, 126-133. - - 1 9 8 0 . [Burovia- a new Horridonia genus (Brachiopoda) from the Selander Formation of the Svalbard Archipelago]. In: SEMEVSKIY,D. V. (ed.) Geologiya Osadochnogo Chekhla Arkhipelaga Sval'bard. Sbornik Nauehnykh Trudov [Geology of the Sedimentary Cover of the Svalbard Archipelago. A Collection of Scientific Papers]. NIIGA, Leningrad, 25-29. - - - & C~RNYAK,G. E. 1973. Marine Upper Paleozoic deposits of the Arctic. Memoir, American Association of Petroleum Geologists, 19, 204-268. UTTJNG, J. 1989. Preliminary palynological zonation of surface and subsurface sections of Carboniferous, Permian and Lowest Triassic rocks, Sverdrup Basin, Canadian Arctic and Archipelago. Geological Society of Canada Papers 1989, 89-1G, 233-240. 1992. Permian palynological assemblages and paleoclimatics Sverdrup Basin, Canada. Geological Association of Canada and Mineral Association of Canada, 25-27 May 1992, Nova Scotia. VAGNES, E. & AMUNDSEN, H. E. F. 1993. Late Cenozoic uplift and volcanism on Spitsbergen caused by mantle convention? Geology, 21, 251-254. --, FALEIDE, J. I., GUDLAUGSSON, S. T. & REKSNES, P. A. 1992. Plate tectonic constraints on Late Cretaceous-Early Tertiary evolution of Svalbard and the Wandel Sea Basin (abstract). Norsk Geologisk Tidsskrift, 72, 140. -

-

511

, REKSNES, P. A., FALEIDE, J. I. & GUDLAUGSSON, S. T. 1988. Plate-tectonic constraints on the formation of the Spitsbergen fold and thrust belt. In: DALEMANN, W. K, OHTA, Y. • ANDRESEN, A. (eds) Tertiary Tectonics of Svalbard. Norsk Polarinstitutt, Report Series, 46, 105-108. VALE, P. R., MITCHUM, R. M., JR. & THOMPSON, S. 1977. Seismic stratigraphy and global changes of sea level, part 4. Global cycles of relative change of sea level. In: PLATON, C. (ed.) Seismic Stratigraphy Applications to Hydrocarbon Exploration. Memoirs of the American Association of Petroleum Geologists, 26, 83-97. VAKULENKO, A. S. 1973. [Paleogene Spore-pollen complexes of Spitsbergen]. In: ZAKLINSKAYA,ME. D. et al. (eds) The Palynology of the Cenophytes. Nauka, Moscow, 109-113. LIVSHITS,Y. Y. 1981. [Palynological characteristics of Palaeogene deposits of Spitsbergen]. Uchenyye Zapiski NlIGA: Paleontologiya i Biostratigrafiya, 31, 39-50. VALLANCE, G. & FORTEY, R. A. 1968. Ordovician succession in north Spitsbergen. Proceedings of the Geological Society of London, 1648, 91-97. VALYUKYAVICHYUS,Y. Y. 1981. Acanthodian scales from the Eifelian of Spitsbergen. Paleontologicheskiy Zhurnal 1979, 482-492 [AGI translation published 1981]. VAN DER Voo, R. 1993. Paleomagnetism in the Atlantic, Tethys and Iapetus Oceans. Cambridge University Press. VAN DER ZWAN, C. J., BOULTER,M. C. & HUBBARD, R. N. L. B. 1985. Climatic change during the Lower Carboniferous in Euramerica based on multivariate statistical analysis of palynological data. Palaeogeography, Palaeoclimatology, Palaeoecology, 52, 1-34. VASlLEVSKAYA, N. D. 1965/1970. [New finds of Fossil Flora in Spitsbergen]. In: SOKOLOV,V. N. (ed.) Materialy po geologii Shpitsbergena. Institute for Geology of the Arctic, Leningrad, 209-221 - - 1 9 7 2 . [The Late Triassic flora of Svalbard]. In: SOKOLOV,V. N. & VASILEVSKAYA, N. D. (eds) Mezozoyskiye otlozheniya Sval'barda [Mesozoic Deposits of Svalbard]. NIIGA, Leningrad, 27-63. - - 1 9 8 0 . [Early Cretaceous flora of Spitsbergen]. In: SEMEVSKIY,D. V. (ed.) [Geology -

-

&

of the Sedimentary Cover of the Svalbard Archipelago. A Collection of Scientific Papers]. NIIGA, Leningrad, 61-69. --I986. [The Early Cretaceous flora of Kapp Selma (West Spitsbergen)]. ln" KRASIL'SHCHmOV, A. A. & MIRZAYEV, M. N. (eds) [The Geology of the Sedimentary Cover of the Spitsbergen Archipelago. A Collection of Papers[. "Sevmorgeo", Leningrad, 94-101. - - 1 9 8 7 . [A new Late Triassic representative of peltaspermic pteridosperrns from Spitsbergen]. Paleontolog&heskiy Zhurna11987, 131-133. VERBA, M. L. 1984. [The structure of the Spitsbergen Shelf from geophysical data]. In: GRAMBERG,I. S. & KULAKOV,YU N. (eds): Neftegazonosnost' Mirovogo okeana [Oil and Gas Content of the Worm Ocean]. "Sevmorgeo", Leningrad, 22-33. -(ed.) 1985. [The Geological Structure of the Barents-Kara Shelf. A Collection of Papers]. "Sevmorgeo", Leningrad. --, DARA~AN-SusHcrIOVA, L. A. & PAVL~NKIN, A. D. 1991. Rifts of the western Arctic shelf based on refraction surveys. Petroleum Geology, 25, 220-225. --, KRASIL'SHCmKOV,A. A. & LIVSmTS, Y. Y. 1981. [Reflection of the basement structure of the Spitsbergen shelf in the magnetic field]. In: PUSHKOV,A. N. (ed.) Anomalii Geomagnitnogo Polya i Glubinnoye Stroyeniye Zemnoy Kory [Geomagnetic Anomalies and the Deep Structure of the Earth's Crust]. "Naukova Dumka", Kiev, 93-95. VERDENrUS, J. G. 1978. A Valanginian calcareous nalmofossil association from Kong Karls Land, Eastern Svalbard. Norsk Polarinstitutt ~lrbok 1977, 350-352. VIDAL, G. 1979. Acritarchs from the Upper Proterozoic and Lower Canlbrian of East Greenland. Bulletin Gronlands Geologiske Undersogelse, 134, 1-55. - - 1 9 8 1 . Micropalaeontology and biostratigraphy of the Upper Proterozoic and Lower Cambrian sequences in East Finnmark, northern Norway. Norges Geologiske Undersokelse, 362, 1-53. --1985. Biostratigraphical correlation of the Upper Proterozoic and Lower Cambrian of the Fennoscandian and the Caledonides of East Greenland and Svalbard. In: GEE, D. G. STURT, B. A. (eds) The Caledonide Orogen - Scandinavia and related areas. Wiley, Chichester, 331-338. & KNOLL, A. H. 1982. Radiations and extinctions of plankton in the Late Proterozoic and Early Cambrian. Nature, 297, 57-60. & - - 1 9 8 3 . Proterozoic plankton. In: MEDARIS, L. G. et al. (eds) Proterozoic Geology: An International Symposium. Memoirs of the Geological Society of America, 161, 265-277. & SEIDEECKA, A. 1983. Planktonic, acid-resistant microfossils from the Upper Proterozoic strata of the Barents Sea region of Varanger Peninsula, East Finnmark, northern Norway. Norges geologiske undersokelse, 382, 45-79. VIGRAN, J. 1964, Spores from Devonian deposits, Mimerdalen, Spitsbergen. Norsk Polarinstitutt Skr~ter, 132, 1-30. V1NCENZ, S. A. & JELENSKA,M. 1985. Palaeomagnetic investigations of Mesozoic and Paleozoic rocks from Svalbard. Tectonophysics, 114, 163-180. --, COSSACK, D., DUDA, S. J., BIRKENMAJER, K., JELENSKA, M., KADZIAEKO HOFMOKL, M. & KRUCZYK, J. 1981. Palaeomagnetism of some Late Mesozoic dolerite dykes of south Spitsbergen. Geophysical Journal of the Royal Astronomical Society, 67, 599-614. --, JELENSKA, M., AUNEHSAZ1AN, K. & BIRKENMAJER, K. 1984. Palaeomagnetism of some late Mesozoic dolerite sills of east central Spitsbergen, Svalbard Archipelago. Geophysical Journal of the Royal Astronomical Society, 78, 751-773. VINJE, T. 1989. Icebergs in the Barents Sea. In: SINHA, N. K., SODHI, D. S. & CHUNG, J. S. (eds) Offshore Mechanics and Arctic Engineering, 4, 139-145. VINOGRADOV, A. V. 1987. [Structure of the Permian and Triassic deposits of the Barents Sea according to M O G T (common depth point method) seismic data]. Izvestiya AN SSSR, Seriya Geologicheskaya 1987, 74-86. -

-

-

-

-

-

512

REFERENCES

VISKOVA, L. A. (ed.) 1986. [Permian Bryozoans of the Arctic' (Western Sector)]. Nauka, Moscow. VolT, P. R., CRANE, K. & SUNDVOR, E. 1994. Deep Pleistocene iceberg plowmarks on the Yermak Plateau: Sidescan and 3.5 kHz evidence for thick calving ice fronts and a possible marine ice sheet in the Arctic Ocean. Geology, 22, 403-406. , FEDEN, R. H., ELDHOLM,O. & SUNDVOR,E. 1978. The ocean crust west and north of the Svalbard archipelago: synthesis and review of new results. Polarforschung, 48, 1 19. , KOVACS,L. C., BERNERO, C. & STRIVASTAVA,S. P. 1982. Asymmetric geophysical signatures of the Greenland-Norwegian and Southern Labrador Seas and the Eurasian Basin. Tectonophysics, 89, 95-160. , SUNDVOR, E., CRANE, K., PFIRMAN, S., NISHIMURA, C. & MAX, M. 1990. SeaMARCII and associated geophysical investigation of the Knipovich Ridge, Molloy Ridge/Fracture Zone, and Barents/Spitsbergen continental margin. Part III: sedimentary processes (abstract). EOS (Transactions of the American Geophysical Union), 71,622. VOaT, T. 1922. [Contributions to the stratigraphy and tectonics of the mountain chain]. GeoIogiska Fdreningens Stockholm FO'rhandlingar, 44, 714 739. 1928. Den norske fjellkjedes revolusjonshistorie. Norsk Geologisk Tidsskrift, 10, 9%115. - - 1 9 2 9 . [Account of the explorations in the summers of 1924-1928]. Norges geologiske undersokelse, 133, 50 65. --1936. Orogenesis in the region of Paleozoic folding of Scandinavia and Spitsbergen. In: 16th International Geological Congress, Report 2, International Geological Congress, Washington, 953 955. - - 1 9 3 8 . The stratigraphy and tectonics of the Old Red formations of Spitsbergen. Abstracts of the Proceedings of the Geological Society of London, 1343, 88. - - 1 9 4 1 . Geology of a Middle Devonian cannel coal from Spitsbergen. Norsk Geologisk Tidsskrift, 21, 1-12. .. VON Buell, L. 1847. Uber Spirifer Keilhavii, fiber dessen Fundort und Verh/iltniss zu fihnlichen Forrnen. Abhandlungen der Preussischen Akademie der Wissenschaften 1846, 65 80. Berlin. VON DRASCHE, R. 1874. Petrographisch-geologische Beobachtungen an der WestKiiste Spitzbergens. Tschermaks Mineralogische und Petrographische Mitteilungen, 3, 181-198. VON DUNIKOWSKL E. 1884. Ueber Permo-Carbon-Schwdmme yon Spitzbergen. Kungliga Svenska Vetenskapsakademiens Handlingar, 21. Stockholm. VON HEUGLIN,M. T. 1872. Beitrdge zur Fauna, Flora und Geologie yon Spitzbergen und Novaja Semlja. Reisen nach dem Nordpolarmeer in den Jahren 1870 und 1871, Part 3. Braunschweig. VON POST, L. 1912. Vulkaner och varma kfiller p~. Spetsbergen [Volcanoes and warm springs in Spitsbergen]. Pop. Naturv. Rev., 2, 49-61. VON WITTENBURG, P. 1910. l~lber einige Triasfossilien yon Spitzbergen. Travaux du

Mus~e Gdologique (et Mineralogique) Pierre le Grand pros I'Acad~mie Impdriale des Sciences de St-Petersbourg, 4, 31 39. - - - 1 9 1 2 . Ueber Werfener-Schichten von Spitzbergen. Bulletin of the Academy o[" Sciences, St. Petersburg 1912, 947 948. VONDERBANK, K. 1970. Geologic und Fauna der Terti~iren Ablagerungen ZentralSpitsbergens. Norsk Polarinstitutt Skr(fter, 153, 1-119. VORREN, T. O. 1992. Glaciation of the Barents Sea - an overview. Sveriges Geologiska Unders6kning, Series C, 81, 367-372. - & KR1STOFFERSEN, Y. 1986. Late Quaternary glaciation in the southwestern Barents Sea. Boreas, 15, 51-59. --, BERGSAGER E., DAHL-STAMNES, "~. A., HOLTER, E., JOHANSEN, B., LIE, E. & LUNO, T. B. (eds) 1993. Arctic Geology and Petroleum Potential. Proceedings of NPF Conference, 15-17 August 1990, Tromso. Elsevier, Amsterdam. , RICHARDSEN,G., KNUTSEN, S.-M. & HENRmSEN, E. 1991. Cenozoic erosion and sedimentation in the western Barents Sea. Marine and Petroleum Geology, 8, 317-340. -, VORREN,K. D., ALM, T., GULLIKSEN,S. S. & LOVLIE,R. 1988. The last deglaciation (20,000 to 11,000 BP) on Andoya, northern Norway. Boreas, 17, 41-77. , LEBESBYE, E., ANDREASSEN, K. & LARSEN, K. B. 1989. Environments in the Barents Sea. Marine Geology, 85, 251 272. VOYTOV, G. I., KRAVTSOV, A. I., TERENT'YEV, Y. V., GORDIYENKO, P. D., BOBROV, V. A. & TEREKHOVA,G. P. 1979. [Features of the chemical composition of gases and the isotope composition of carbon in carbonaceous compounds of the Barentsburg deposit (West Spitsbergen)]. Doklady Akademii Nauk SSSR, 248, 205-208, 1221-1224. WADDAMS, P. 1983. The late Precambrian succession in northwest Oscar li Land, Spitsbergen. Geological Magazine, 120, 233-252. - - 1 9 8 3 . Late Precambrian resedimented conglomerates from Bellsund, Spitsbergen. Geological Magazine, 120, 153 164. WADHAM, J. L., HODSON, A. S., TRANTER, M. & DOWDESWELL,J. A. 1997. The rate of chemical weathering beneath a quienscent, surge-type glacier in Svalbard. Annals' of" Glaciology, 24, 27-3 I. WAGNER, G. 1965. Klimatologische Beobachtungen in Sfidostspitzbergen 1960. Ergebnisse der Stauferland-Expedition 1959/1960 (Deutsche Expedition nach Siidostspitzbergen). Heft 10. Pub. Frank Steiner Verlag GMBH, Wiesbaden 1965. WALLIS, R. H. 1969. The Planetfjella Group of the lower Hecla Hoek of Ny Friesland, Spitsbergen. Norsk Polarinstitutt ~lrbok 1967, 80-108. , HARLAND, W. B., GEE, D. G. & GAYER, R. A. 1968. A scheme of petrographic nomenclature for some metamorphic rocks in Spitsbergen. Norsk Polarinstitutt .4rbok 1966, 25-37. & 1969. "A scheme of petrographic nomenclature" - a reply. Norsk Polarinstitutt /{rbok 1967, 135-145. WALNIUK, O. M. & MORRIS, A. P. 1985. Quartz deformation mechanisms in metasedilnents from Prins Karls Forland, Svalbard. Tectonophysics, 115, 87-100.

WALTON, J. 1927. On some fossil wood of Mesozoic and Tertiary age from the Arctic zone. Annales of Botany, Oxford, 41, 239-252. WANGSJO, G. 1937. On a new species of Benneviaspis from Red Bay Series in Spitsbergen. Bulletin of the Geological Institution of the University of Uppsala, 27, 209-211. - - 1 9 5 2 . The Downtonian and Devonian vertebrates of Spitsbergen. IX. Morphologic and systematic studies of the Spitsbergen Cephalaspids. Norsk Polarinstitutt Skrifter, 97, 1-611. WATTS, D. R. 1985. Palaeomagnetism of the Lower Carboniferous Billefjorden Group, Spitsbergen. Geological Magazine, 122, 383-388. WEBBY, B. D. E. & LAURIE,J. R. (eds) 1992. Globalperspectives on Ordovician geology. Balkema, Netherlands. WE~ENER, A. 1924. The Origin of Continents and Oceans. Metheun [Translation by J. G. A. Skerl from Die Entstehung der Kontinente und Ozeane 1922]. WEGMANN, C. E. 1948. Geological tests of the hypothesis of continental drift in the Arctic Regions, Scientific Planning. Meddedelelser om Gronland, 144. WEIGAND, P. W. & TESTA, S. M. 1982. Petrology and geochemistry of Mesozoic dolerites from the Hinlopenstretet area, Svalbard. Polar Research, 1, 35-52. WEIR, J. t933. Mesozoic fossils from Spitsbergen collected by Dr. G. W. Tyrrell. Transactions of the Royal Society of Edinburgh, 5 7 , 675 690 [appendix to 'Stratigraphical observations in the Stor Fjord region of Spitsbergen' by G. W. Tyrrell]. WEISS, L. E. 1953. Tectonic features of the Hecla Hock Formation to the south of St. Jonsfjord, Vestspitsbergen. Geological Magazine, 90, 273-286. - - 1 9 5 8 . The structure of the Trygghamna-Vermlandryggen area, Isfjorden. Norsk Geologisk Tidsskrift, 38, 218-219. WEITSCHAT, W. 1983. Ostracoden (O. Myodocopida) mit Weichk6rper-Erhaltung aus der Unter-Trias von Spitzbergen. Palaeontologische Zeitschrift, 57, 309-323. - - 1 9 8 6 . Phosphatisierte Ammonoideen aus der Mittleren Trias von CentralSpitzbergen [Phosphatised anamonoids from the Middle Triassic of central Spitsbergen]. Mitteilungen aus dem Geologisch-Paldontologischen lnstitut der Universitfft Hamburg, 61, 249-279. -& DA~YS, A. S. 1989. Triassic biostratigraphy of Svalbard and a comparison with NE-Siberia. Mitteilungen aus dem Geologisch-Paldontologischen lnstitut der Universitdtt Hamburg, 68, 179-213. - & LEr~MANN, U. 1978. Biostratigraphy of the uppermost part of the Smithian Stage (Lower Triassic) at Botneheia, W. Spitsbergen. Mitteilungen aus dern Geologisch-Paldontologischen lnstitut der Universitdt Hamburg, 4 8 , 85 100. - & 1983. Stratigraphy and ammonoids from the Middle Triassic Botneheia Formation (Daonella shales) of Spitsbergen. Mitteilungen aus dem GeologisehPaldontologischen Institut der Universitdt Hamburg, 54, 27-54. WELBON, A. I. & ANDRESEN, A. 1992. The Pretender Lineament-structural and stratigraphic significance of a major lineament in western Spitsbergen. Norsk Geologisk Tidsskrift, 72, 139 (abstract). -~ & MAHER, H. D. JR. 1992. Tertiary tectonism and basin inversion of the St. Jonsfjorden region, Svalbard. Journal of Structural Geology, 14, 41-55. WENDORFF, M. 1985. Geology of Palflyodden area (NW Sorkapp Land, Spitsbergen) and some results of the investigations. Zeszyty naukowe Universytetu Jagiellonskiego, Prace Geograficzne, 63, 33-55. WENNBERG, O. P., ANDRESEN, A., HANSEN, S. & BER6H, S. G. 1994. Structural evolution of a frontal ramp section of the West Spitsbergen Tertiary fold and thrust belt, north of Isfjorden, Spitsbergen. Geological Magazine, 131, 67-80. --, HANSEN, S. & ANDRESEN, A. 1992. A geometric and kinematic analysis of the eastern margin of the Tertiary fold belt north of Isfjorden, Oscar 1I Land, Spitsbergen (abstract). Norsk Geologisk Tidsskrift, 72, 139-140. WERENSKIOLD, W. 1919. [Deposits of ores and useful minerals in Spitsbergen]. Tidsskrift Bergv. Aarg., 7, 149-152. - - 1 9 2 0 . [The country between Hornsund and Bellsund, Spitsbergen. Observations made in 1917 and 1918]. Naturen. Aarg., 44, 246-254. - - 1 9 2 6 . Contributions to the natural history of Hope Island. Physical geography and geology; coal deposits, ln: IVERSEN,T. (ed.) Hopen (Hope Island), Svalbard. Resultater Norske Spitzbergenekspeditioner, 1(10), 25-27. -& OFTEDAHL, I. 1922. A burning coal seam at Mt. Pyramide, Spitsbergen.

Resultater Norske Spitzbergenekspeditioner, 1. WERNER, A. 1990. Lichen growth rates for the northwest coast of Spitsbergen, Svalbard. Arctic and Alpine Research, 22, 129-140. --1993. Holocene moraine chronology, Spitsbergen, Svalbard: lichenometric evidence for multiple Neoglacial advances in the Arctic. The Holocene, 3, 12-137. WEST, R. M., DAWSON, M. R., HICKEV, L. J. & MIALL, A. D. 1981. Upper Cretaceous and Paleogene sedimentary rocks, eastern Canadian Arctic and related North Atlantic areas. In: KERR, J. W., FER~USSON, A. J. & MACHAN,L. C. (eds) Geology of the North Atlantic Borderlands. Memoirs of the Canadian Society of Petroleum Geologists, 7, 279-298. WESTOLL, T. S. 1951. The vertebrate bearing strata of Scotland. Reports of the 18th Session of International Geological Congress, Great Britian 1948, Part II, 5-21. WHITE, E. I. 1956. Preliminary note on the range of the Pteraspids in Western Europe. Bulletin de l'Institut Royal des Sciences Naturelles de Belgique, 32, 1-10. WHITTINGTON, H. B. 1968. Ordovician faunas from Ny Friesland, north-central Spitsbergen. Proceedings of the Geological Society of' London, 1648, 74. WIERZBOWSKI, A. 1988. [The succession of the Kimmeridgian ammonite faunas in Spitsbergen]. In: JAHN, A., PEREYMA,J. & SZCZEPANKIEWICZ-SZMYRKA,A. (eds) XV

- -

Sympozjum Polarne. Stan obecny i wybrane problemy polskich badan polarnych, Wroclaw 19~1 May 1988. Wydawnictwo Uniwersytetu Wroclawskiego, Warsaw, 12-19. & fikRHUS, N. 1990. Ammonite and dinoflagellate cyst succession of an Upper Oxfordian-Kimmeridgian black shale core from the Nordkapp Basin, southern Barents Sea. Newsletters on Stratigraphy, 22, 7-19.

REFERENCES & SMELROR, M. 1993. Ammonite succession in the Kimmeridgian of southwestern Barents Sea, and the Amoeboceras zonation of the Boreal Kimmeridgian. Acta Geologica Polonica, 43. , KULICKI, C. & PUGACZEWSKA,H. 1981. Fauna and stratigraphy of the uppermost Triassic and the Toarcian and Aalenian deposits in the Sassenfjorden, Spitsbergen. Acta Palaeontologica Polonica, 26, 195-241. WIGNALL, P. B. t~ TWITCHETT,R. J. 1996. Oceanic anoxia and the End Permian mass extinction. Science, 272, 1155-1158. - - , MORANTE, R. & NEWTON, R. 1998. The Permo-Triassic transition in Spitsbergen: 6~3Corg chemostratigraphy, Fe and S geochemistry, facies, fauna and trace fossils. Geological Magazine, in press. WILLIAMS, G. F. 1994. The enigmatic Late Proterozoic glacial climate: an Australian perspective. In: DEYNOUX, M. et al. (eds) Earth's Glacial Record. Cambridge University Press, 146-164. WILLIAMS,P. J. & SMITH,M. W. 1989. The Frozen Earth:fundamentals of Geocryology. Cambridge University Press. WILSON, C. B. 1958. The Lower Middle Hecla Hoek rocks of Ny Friesland, Spitsbergen. Geological Magazine, 95, 305 327. - - 1 9 6 1 . The Upper Middle Hecla Hock rocks of Ny Friesland, Spitsbergen. Geological Magazine, 98, 89-116. & HARLAND, W. B. 1964. The Polarisbreen Series and other evidences of Late Pre-Cambrian ice ages in Spitsbergen. Geological Magazine, 101, 198-219. WILSON, J. T. 1966. Did the Atlantic close and then re-open? Nature, 211,657-681. W~MAN, C. 1910a. Ein Paar Labyrinthodontenreste aus der Trias Spitzbergens. Bulletin of the Geological Institution of the University of Uppsala, 9, 34-40. - - 1 9 1 0 b . Ichtyosaurier aus der Trias Spitzbergens. Bulletin of the Geological Institution of the University of Uppsala, 10, 124 148. - - 1 9 1 3 a . 15ber das Hinterhaupt der Labyrinthodonten. Bulletin of the Geological Institution of the University of Uppsala, 12, 1-8. - - 1 9 1 3 b . Ein Plesiosaurierswirbel aus dem jungeren Mesozoicum Spitzbergens. Bulletin of the Geological Institution of the University of Uppsala, 12, 201. - - 1 9 1 4 a . Ein Plesiosaurierwirbel aus der Trias Spitzbergens. Bulletin of the Geological Institution of the University of Uppsala, 12, 201--204. 1914b. l~Iber die Stegocephalen aus der Trias Spitzbergens. Bulletin of the Geological Institution of the University of Uppsala, 13, 1-34. 1914c. ()ber die Karbonbrachiopoden Spitzbergens und Beeren Eilands. Nova Acta Soc. Sci. Uppsala, Ser. 4, 3, 1-91. - - - 1 9 1 6 a . Neue Stegocephalenfunde aus dem Posidonomyaschiefer Spitzbergens. Bulletin of the Geological Institution of the University of Uppsala, 13, 209-222. - - 1 9 1 6 b . Ein Plesiosaurierwirbel aus der Trias Spitzbergens. Bulletin of the Geological Institution of the University of Uppsala, 13, 223-226. - - 1 9 1 6 c . Notes on the marine Triassic reptile fauna of Spitzbergen. Bulletin of the Department of Geology, University of California, 10, 63-73. - - 1 9 1 7 . lJber die Stegocephalen Tertrema und Lonchorhynhus. Bulletin of the Geological .. Institution of the University of Uppsala, 14, 229-240. - - 1 9 1 8 a . Uber Gehirn und Sinnesorgane bei Tremataspis. Bulletin of the Geological Institution of the University of Uppsala, 16, 86-95. - - 1 9 1 8 b . Ein Archosaurier aus der Trias Spitzbergens. Bulletin of the Geological Institution of the University of Uppsala, 16, 81-85. - - 1 9 2 8 . Eine neue marine Reptilien-Ordnung aus der Trias Spitzbergens. Bulletin of the Geological Institution of the University of Uppsala, 22, 183-196. - - 1 9 3 3 . (lber Grippia Longirostris. Nova Acta Soc. Sci. Uppsala, Ser. 4, 9, 1-19. WINSNES, T. S. 1955. A preliminary description of the Hecla Hoek rocks and its Cambrian and Ordovician faunas. In: MASOR, H. & WtNSNES, T. (eds) Cambrian and Ordovician fossils from Sorkapp Land, Spitsbergen. Norsk Polarinstitutt Skrifter, 106, 31-47. - - 1 9 6 5 . The Precambrian of Spitsbergen and Bj~rnoya. In: RAUHAMA, K. (ed.) The Precambrian, 2. The Geologic Systems. Wiley, London, 1-24. - - 1 9 6 6 . Observations on the Carboniferous and Permian rocks of Vestspitsbergen. Norsk Polarinstitutt ~lrbok 1964, 7-29. - - 1 9 7 5 . Geological background: Svalbard. In: Arctic Oil and Gas, Problems and Possibilities. CNRS, Colloques International, 12, 56-78. - - 1 9 7 9 . The geological development of Svalbard during the Precambrian, Lower Paleozoic and Devonian. Norsk Polarinstitutt Skrifter, 167, 1-324. - - 1 9 8 8 . Bedrock map of Svalbard and Jan Mayen. Scale l:l,000,000. Norsk Polarinstitutt, Temakart, 3. & OIaTA, Y. 1988. Fold structures of Carboniferous to Triassic rocks in the inner part of St. Jonsfjorden. In: DALLMANN,W. K., OHTA, Y. & ANDRESEN, A. (eds) Tertiary Tectonics of Svalbard. Norsk Polarinstitutt, Report Series, 46, 21-24. - - & WORSLEY, D. 1981. Geological Map ofSvalbard. 1 : 500 000. Sheet 2G. Edgeoya. Norsk Polarinstitutt, 154B. --, BIRKENMAJER, K., DALLMANN, W. K., HJELLE, A. t~ SALVIGSEN, O. 1993. Geological Map of Svalbard, 1 : 100,000 sheet C13G. Sorkapp. Norsk Polarinstitutt. Temakart 7. - - , HE1NTZ, A., HEINTZ, N., BIRKENMAJER,K. & DONS, J. A. (eds) 1960. Aspects of the Geology of Svalbard. Guide to excursion A.16. International Geological Congress, Norden [also in Norges geologiske undersokelse, 212]. WITTENBURG, P. 1910. 13her einige trias fossilien yon Spitsbergen. Travaux du Music g~ologique Pierre le Grand, 4, 31-39. - - 1 9 1 2 . Ueber Werfener-Schichten yon Spitzbergen. Bulletin of the Academy of Sciences, St. Petersburg, 6, 947-948. WITT-NILSSON, P. 1997. Middle crust transpressional deformation of the Caledonian Lower Hecla Hock Complex, Svalbard (abstract). In: Continental Transpressional and Transtensional Tectonics, Geological Society, London, 5-6 March 1997. --

-

-

513

, GEE, D. G. & HELLMAN, F. J. 1997. The Atomfjella Antiform of northern Ny Friesland, Svalbard Caledonides. Norsk Geologisk Tidsskrift, in press. WOHLEARTH, B., LEMDAHL, G., OLSSON, S., PERSSON, T., SNOWBALL,I., ISING, J. & JONES, V. 1995. Early Holocene environment on Bjornoya (Svalbard) inferred from multidisciplinary lake sediment studies. Polar Research, 14, 253-275. WOJCIECI.IOWSKI,J. 1964. Ore-bearing veins of Hornsund area, Vestspitsbergen (preliminary communication). In: BIRKENMAJER, K. (ed.) Geological Results of the Polish 1957-1958, 1959, 1960 Spitsbergen Expeditions, Part 3. Studia Geologica Polonica, 11, 173-177. WOJCIK, C. 1981. Geological observations in the eastern part of the Forlandsundet Graben between Dahlbreen and Engleskbukta, Spitsbergen. In: BIRKENMAJER,K. (ed.) Geological Results of the Polish Spitsbergen Expeditions. Studia Geologica Polonica, 72, 25-35. WOOD, R. J., EDRICH, S. P. & HUTCHISON, I. 1989. Influence of North Atlantic tectonics on the large-scale uplift of the Stappen High and Loppa High, Western Barents Shelf. In: TANKARD, A. J. & BALKWILL,H. R. (eds) Extensional tectonics and stratigraphy of the North Atlantic Margins. American Association of Petroleum Geologists, Memoirs, 46, 559-566. WOODWARD, A. S. 1891. The Devonian fish-fauna of Spitzbergen. Annals and Magazine of Natural History, Series 6, 8, 1-15. - - 1 9 0 0 . Notes on fossil fish-remains collected in Spitzbergen by the Swedish Arctic Expedition, 1898. Kungliga Svenska Vetenskapsakademiens Handlingar, 25. Stockholm. - - 1 9 0 4 . On two new Labyrinthodont skulls of the genera Capitosaurus and Aphaneramrna. Proceedings of the Zoological Society 1904. - - 1 9 1 2 . Notes on some fish remains from the Lower Trias of Spitzbergen. Bulletin of the Geological Institution of the University of Uppsala, l l , 291-297. WORDIE, J. M. 1921. Present day conditions in Spitsbergen. Geographical Journal, 63, 25-49. WORSLEY, D. 1972. Sedimentological observations on the Grey Hoek Formation of northern Andr~e Land, Spitsbergen. Norsk Polarinstitutt ~lrbok 1970, 102-11 I. - - 1 9 7 3 . The Wilhelmoya F o r m a t i o n - a new lithostratigraphical unit from the Mesozoic of eastern Svalbard. Norsk Polarinstitutt Arbok 1971, 7-13. - - 1 9 8 5 . Svalbard's Late Paleozoic and Early Mesozoic sequence. In: Upper Paleozoic and Lower Mesozoic Stratigraphy of Arctic Basins. NPF Symposium held at Stavanger 19 February 1985, 35-45. - - 1 9 8 6 . Evolution of an arctic archipelago: The Geological History of Svalbard. In: AGA, O. J. (ed.). Statoil, Stavanger. - - 1 9 8 7 . The lithostratigraphic scheme for Tromsoflaket in a regional structural framework (abstract). Norsk Geologisk Tidsskrift, 67, 438-439. - - 1 9 8 8 . Late Paleozoic and Mesozoic history of Svalbard. In: DALLMANN, W. K., OHTA, Y. • ANDRESEN, A. (eds) Tertiary Tectonics of Svalbard. Norsk Polarinstitutt, Report Series, 46, 13-14. -& EDWARDS, M. B. 1976. The Upper Palaeozoic succession of Bjornoya. Norsk Polarinstitutt ,4rbok 1974, 17-34. t~ GJELBERG,J. 1980. Excursion guide to Bj~rnoya, Svalbard. Contributionsfrom the Paleontological Museum, Oslo, Norway, 258, 1-33. & HEINTZ, N. 1977. The stratigraphical significance of a marine vertebrate fauna of Rhaetian age, Kong Karls Land. Norsk Polarinstitutt ~lrbok 1976, 69-81. -& MORK, A. 1978. The Triassic stratigraphy of southern Spitsbergen. Norsk Polarinstitutt .4rbok 1977, 43-60. -& - - 1 9 8 1 . Excursion guide to Isfjorden. IKU, Trondheim. - - - , AGDESTEIN,T., GJELBERG,J., KIRKEMO, K. & STEEL, R. J. 1987. Late Paleozoic basinal evolution and stabilisation of Bjorn~ya- implications for the Barents Shelf. In: MoP,X, A. (ed.) GeologicalExcursion Guide to Bjornoya. IKU, Trondheim. - - , JOHANSEN,R. & KRISTENSEN,S. E. 1988. The Mesozoic and Cenozoic succession of Tromsoflaket Norwegian Petroleum Directorate Bulletin, 4, 42-63. WRIGHT, N. J. R. & HENDERSON, W. G. 1976. Small-scale drilling in Spitsbergen. Norsk Polarinstitutt Arbok 1974, 101-107. WRONA, R. M. 1977. Troschiliscus (Eutrochiliscus) cf. bulbiformis Karpinsky (Charophyta) in the Devonian limestone of Traunkammen, Spitsbergen. Acta Palaeontologica Polonica, 22, 289-296. - - 1 9 8 2 . Early Cambrian phosphatic microfossils from southern Spitsbergen (Hornsund region). In: BIERNAT, G. & SZYMANSKA, W. (eds) Palaeontological Spitsbergen Studies. Palaeontologica Polonica, 43, 9-16. Wu, R. T. 1984. A new Carboniferous trilobite from Spitsbergen. Geological Magazine, 121, 475-481. YAKOBSON, K. E. 1987. [Paragenesis of glacial and chemogenic deposits in the Upper Precambrian]. Doklady Akademii Nauk SSSR, 295, 1429-1432. YAKOVLEV, N. 1903. Neue Funde yon Trias-Saurien auf Spitzbergen. Verhandlungen -

-

-

-

der Russisch-Kaiserlichen Mineralogischen Gesellschaft zu St. Petersburg, Series 2, 40, 179-202. - - 1 9 0 3 . Einige Bemerkungen fiber die triassischen Ichtyosaurien. Verhandlungen der Russisch-Kaiserlichen Mineralogischen Gesellschaft zu St. Petersburg, Series 2, 40, 263 -266. - - 1 9 0 4 . Nachtrag zu meiner Abhandlung "Neue Funde yon Trias-Saurien auf Spitzbergen" und Bemerkungen zu der von Prof. Koken verfassten Recenzion dieser Abhandlung. Verhandlungen der Russisch-Kaiserlichen Mineralogischen Gesellschaft zu St. Petersburg, Series 2, 41, 165-169. YEFREMOVA, V. I., DITMAN, A. V. & TARAKOVSKIY,A. N. 1983. [New data on the stratigraphy of the Middle to Upper Jurassic of Champ Island, Franz Josef Land]. In: BONDAREV,V. I. (ed.) Palaeontological basis for the division of the Palaeozoic and Mesozoic of the Arctic regions of the USSR. PGO "Sevmorgeologiya", Leningrad, 63~6. - - , MEEEDINA,S. V. & NAL'NYAYEVA,Z. I. 1983. [Jurassic cephalopods from Champ Island (Franz Josef Land)]. In: ZAKHAROV,V. A. & NAL'NYAYEVA, T. I. (eds) Trudy Instituta Geologii I Gefiziki, 555, 125-154.

514

REFERENCES

YERMOLAYEV, M. M. 1937. [Geological review of Svalbard. Explanatory note to the geological map of the northern part of the USSR (scale 1: 2500000)]. In: YEP,MOLAVEV,M. M. & PETRENKO,A. A. (eds) Trudy Arkt. Inst., 87, 29-68. YERSI-IOV, Yr. P., KRASIL'SrICIJIKOV,A. A., VOLVO,V. E. & S m M A ~ V , V. N. 1974. [Geote&onic characterisation of the southern part of the Barents Sea shelf]. In: [Geotectonic preconditions for the search for useful minerals on the shelf of the Arctic Ocean]. NIIGA, Leningrad, 34-50. YERSHOVA, YE. S. 1969. [New finds of Late Volgian ammonites in Spitsbergen]. Uchenyye Zapiski NIIGA: Paleontologiya i Biostratigrafiya, 26, 52-69. - - 1 9 7 2 a . [Some Berriasian ammonites of the island of Spitsbergen]. In: SOIr V. N. & VASILEVSKAYA, N. D. (eds) Mezozoyskiye otlozheniya Sval'barda [Mesozoic Deposits of Svalbard]. NIIGA, Leningrad, 82-89. - - 1 9 7 2 b . [Hauterivian ammonites of the island of Spitsbergen]. ln: SOKOLOV,V. N. & VASILEVSKAVA,N. D. (eds) Mezozoyskiye otlozheniya Sval'barda [Mesozoic Deposits of Svalbard]. NIIGA, Leningrad, 90-99. - - 1 9 8 0 . [Some Early Valanginian ammonites from Spitsbergen]. In: SEMEVSKJV, D. V. (ed.) Geologiya osadochnogo chekhla arkhipelaga Sval'bard. Sbornik nauchnykh trudov [Geology of the Sedimentary Mantle of the Svalbard Archipelago. A Collection of Sc&ntific Papers']. NIIGA, Leningrad, 70-80. - - 1 9 8 3 . [Explanatory notes to Biostratigraphic Scheme of Jurassic and Lower Cretaceous' deposits of the Spitsbergen Archipelago]. Ministerstvo Geologii SSSR, PGO "Sevmorgeologiya", Leningrad. -& PCI~ELINA,T. M. 1982. [Boundary deposits of the Upper Jurassic and Lower Cretaceous of Spitsbergen]. ln: SAKS,V. N. (ed.) Verkhnyayayura igranitsayeyes melovoy sistemoy [The Upper Jurassic and its boundary with the Cretaceous system]. Nauka, Novosibirsk, 44-48. -& REWN, Y. S. 1983. [Toarcian and Aalenian ammonites from the Spitsbergen Archipelago]. In: KRASIL'SHCHIKOV, A. A. & BASOV, V. A. (eds) Geologiya Shpitsbergena: sbornik nauchnykh trudov [The Geology of Spitsbergen: a Collection of Papers]. "Sevmorgeo", Leningrad, 50 170. YEVOOKIMOVA, N. K. 1980. [Features of the distribution of organic matter in the sedimentary deposits of the Svalbard Archipelago]. In: SEMEVSKIY,D. V. (ed.) Geologiya osadochnogo chekhla arkhipelaga Sval'bard. Sbornik nauchnykh trudov [Geology of the Sedimentary Cover of the Svalbard Archipelago. A Collection of Scientific Papers]. NIIGA, Leningrad, 110-120. - - 1 9 9 6 . Composition and quality of coals of Spitsbergen. In: KRASIL'SHCm~r A. A. (eds) Soviet Research in Svalbard 1962-1992. Norsk Polarinstitutt Mcddelelser, 139, 99 (Oslo 1996). , VOROKHOVSKAVA,A. M. & BIRVUKOV, A. S. 1986. Composition of the Lower Carboniferous coal-bearing sequence of West Spitsbergen. Geologiya osadochnogo chekhla arkhipelaga Shpitsbergen, Sevmorgeologiya, 20-23. YOCHELSON,E. L. 1966. Some new Permian gastropods from Spitsbergen and Alaska. Norsk Polarinstitutt ,4rbok 1965, 31-35. YOSHIKAWA, K. & NAKAMURA, T. 1996. Pingo growth ages in the delta area, Adventdalen, Spitsbergen. Polar Record, 32, 347. YOUNG, G. M. 1995. Are Neoproterozoic glacial deposits preserved on the margins of Laurentia related to the fragmentation of two supercontinents. Geology, 23, 153-156.

ZAGORODNOV, V. S., ZJNrER, Y. M., TROITSKIY, L. S. & ARKHIPOV, S. M. 1988. [Completion of deep drilling on Austfonna]. Materialy Glyatsiologicheskikh Issledovaniy, 61, 184.

ZAKHAROV,V. A. 1981. [Buchiids and the biostratigraphy of the Boreal Upper Jurassic and Neocomian]. Trudy IGIG SO AN SSSR, 458, 1-271. , SURLYK, F. & DALLAND, A. 1981. Upper Jurassic-Lower Cretaceous Buehia from Andoy, northern Norway. Norsk Geologisk Tidsskrift, 61, 261-269. ZAKnAROV, Y. D. & ONOPRWENKO,Y. I. (eds) 1987. Problemy Biostratigrafii Permi i Triasa Vostoka SSSR [Problems of the biostratigraphy of the Permian and Triassic of the eastern USSR]. DVNTs, Biological-Pedological Institute, Vladivostok. ZAKHAROV, Y. V. & KULIBAKINA,L B. 1989. [Potential of the Jurassic complex of Arctic seas of the USSR for hydrocarbon exploration]. Sovetskaya Geologiya, 5, 33-38. - & - - 1 9 9 4 . [Temperature and gravitation anomalies - criteria of oil and gas content of Barents Sea Shelf]. Geologiya Nefti i Gaza, 8, 2-4. ZALASIEWICZ, J. A., RuswroN, A. W. A. & OWEN, A. W. 1995. Late Caradoc graptolitic faunal gradients across the Iapetus Ocean. Geological Magazine, 132, 611-617. ZAN6, W. & WALTER, M. R. 1992. Late Proterozoie and Cambrian mierofossils and biostratigraphy, Amadeus Basin, Central Australia. Association of Australasian Palaeontologists Memoirs, 12. ZASPELOVA, V. S., Zn~6AVTE, V. K., MOL~, V. A. et al. 1972. [New Palaeozoic and early Mesozoic conchostracans from the U.S.S.R. and Spitsbergen]. In: Novyye vidy drevnikh rasteniy i bespozvonochnykh SSSR. Akadamii Nauk SSSR, Moscow, 247-254. ZASTAWNIAn, E. 1981. Tertiary plant remains from Kaffioyra and Sarsoyra, Forlandsundet, Spitsbergen. In: BmKENMAJER, K. (ed.) Geological Results of the Polish Spitsbergen Expeditions. Studia Geologica Polonica, 72, 37-42. ZAV'rZEV, A. F. 1917. [Spitsbergen coal]. Isvestiya Uprav. po Soyuz Murmanskoi zel. dor. Ekonomoceskie izyskania Ill, Petrograd. ZETZSCHE,P. 1921. Steinkohle auf Spitzbergen. Zeitschriftffir Praktische Geologie, 29, 118 124. ZHmMUrqSKIV, A. M. 1927. [Fauna of the Upper Jurassic and Lower Cretaceous deposits of Spitsbergen]. Trudy Plovuchego Morskogo Nauchnogo Instituta, 2, 89-115. ZmJ GUOQIANG & CR.nDDOCrr C. 1987. [The folding characteristics and tectonic evolution of Hecla Hoek sequence of Wedel Jarlsberg Land, Spitsbergen]. Journal of Chengdu College of Geology, 14, 19 [in Chinese]. ZHURALEV, A. Yu. & WOOD, R. 1996. Anoxia as a cause of the mid-Early Cambrian (Botomian) extinction event. Geology, 24, 311-314. ZIAJA, W. & SALVIGSEN,O. 1995. Holocene shoreline displacement in southernmost Spitsbergen. Polar Research, 14. ZmGLER, A. M., PARRISH,J. T. & SCOTESE,C. R. 1981. Cambrian World Paleontology. U.S. Geological Survey, Open File Report. ZIEGLER, P. A. 1978. North Western Europe: tectonics and basin development. Geologie en Mijnbouw, 57, 589-626. - - 1 9 8 8 . Evolution of the Arctic-North Atlantic and the Western Tethys. Memoirs of the American Association of Petroleum Geologists, 43. ZONENSrtAm, L. P. & NATAPOV,L. M. 1989. Tectonic history of the Arctic region from the Ordovician through the Cretaceous. In: HERMAN, Y. (ed.) The Arctic Seas. Climatology, Oceanography, Geology, and Biology. Van Nostrand Reinhold, New York, 829-862.

General Index This excludes references to place names and stratigraphic unit names as these are covered in separate lists. Pages numbers in italics refer to Figures and Tables

abbreviations in names 7 Abeloya 83 acritarchs 233-4, 248 Admiralty 16 Admiralty chart 16 Adriabukta folding (HSDT) 33 aerial photography 18 aeromagnetic survey 422-3 Agardhbukta Lineament 344 Albert I Land 299-300 Albian-Aptian events 382 ammonite zonation 369-71,354, 378 AMOSEAS 20 amphibolites 123, 165, 283-4 Amundson, R. 19 Andr~e Land-Dickson Land Terrane (ADLT) 32, 33, 147-8, 285, 301 anhydrite 67, 310, 454 Anisian environments 358 anoxia, Early Siberian 260 anoxic facies 356-7 angiosperms 11 annelid worms fossil 379 living 10 anthracite 227, 450 aplite dykes 106, 142 Aptian-Albian events 382 Arc of Meridian Project 16 Arc of Meridian Surveys 76, 96 Archean 151,229 Arktikugol 13 arthropods fossil 293, 394 living 10, Artinskian events 333 Asselian Sakmarian events 332-3 Atomfjella antiform 27, 124 Atomfjella arch 123 Atomfjella Complex 123 augen gneiss 283 Austfjorden tectonothermal event 33 Austfonna 96 Axel Heiberg Island 36

Backlund, H. G. 18, 76 baked sediment 85 Balliolbreen Fault 112, 305 Baltica 253-4, 287 Bangenhuken anticline 27 Bangenhuk granitoid 124 Barents craton/Barentsia 108, 287 Barents Sea 5, 8, 209, 350, 368 Barents shelf 7, 424, 427-8 petroleum potential 20 structural elements 26 Barents, W 16 Barentsburg 13, 388 Barentsoya biostratigraphy 89-91 ice cover 436 igneous bodies 91 lithic units 87-9, 350 Barentsoya Edgeoya Platform Terrane (BEPT) 32, 36 barite 454 Barremian events 382 basalts 76, 84, 85

basement Bjornoya 219-20 sequences 32 structures 27 see also proto-basement Bashkirian-Moscovian events 330-1 basic igneous petrography 76 basic layers 106 Bathonian transgression 363 Bathonian-Tithonian events 381-2 bathymetric chart sheet lines 14 bathymetry 7-8, 420 bay ice 8 Bear Island see Bjornoya belemnites 371-2, 378-9 bentonite 454 Berriasian stage 369 Berzeliustinden 203 Bibliography of Svalbard 20 Billefjorden Fault Zone (BFZ) 26, 70, 129, 146-7, 285, 301-3, 303-5, 316, 409 Billefjorden Lineament 53, 363 Billefjorden Trough 70, 315, 344 biota living 10 fossil Paleogene 393-4 Jurassic-Cretaceous 378-80 Triassic 353-6 Carboniferous-Permian 324-8 Devonian 291-6 Silurian 272 Cambro-Ordovician 260-4 Vendian 248-9 Pre-Vendian 231-5 birds 10 Biskayerfonna Horst 149 Biskayerfonna-Holtedahlfonna Horst 148 Biskayerfonna-Holtedahlfonna terrane (BHFT) 32, 33, 148-50, 230, 285, 300-1 bivalves 294, 372, 379, 394 Bjornoya 212 biota Cambro-Ordovician 260 Vendian 248 coal 450 cover sequences 36 lithic units 210, 257 Paleozoic 212-19 pre-Vendian 231 Triassic 212-13, 350, 361 palinspastic reconstructions 269 structure 219-22 tectonic setting Cambro-Ordovician 266 Silurian 280 volcanic rocks 252 Bjornoya Basement Terrane (BOBT) 32, 34 Bjornoya Basin 315-16 Bjornoya Platform Terrane (BOPT) 32, 36 Black Carbonate Pelite (BCP) 167 Blomstrand, C. B. 16 Blomstrandhalvoya graben-syncline 27 Blomstrandhalvoya Basins 150-1,300 Bonnia-Holmia faunas 259, 264 bornite 189 Botniahalvoya 103 Botniahalvoya unconformity (NAWT) 32 Botonian-Toyonian faunas 259, 264

boudinage 276, 288 boundary faults 316 brachiopods 272, 327, 379 Breibogen Fault 48, 148, 301,305 Breibogen Fault Zone 26, 316 Brentskardhaugen Bed 58, 363, 373, 374 Broggerhalvoya structure 168 Bruce, W. S. 16 bryophytes fossil 394 living 11 bryozoans 327-8, 355 Byrd, R. 19

13C plot 249 calc-alkalic basites 106 calcite 189 Caledonian (Ny Friesland) Orogeny 33, 34, 36, 151, 192, 219, 288 structures 204 vergencies 278, 280 Calypsobyen coal 388 Calypsostranda Basin 180, 449 Cambrian basal unconformity 266 early diastrophism 266 lithic units 116-17, 192 time scale 259, 260 see also Cambro-Ordovician Cambridge Arctic Shelf Programme (CASP) 22 Cambridge University expeditions 18, 389 Cambridgebreen Shear Zone 129, 305 Cambro-Ordovician biotas 260-2 correlation within Svalbard 262-4 palinspastics 268-70 sedimentary environments 264-6 tectonic environments 266-8 tectonothermal events 270-1 terranes 268-70 Carnian environments 358-60 Carboniferous biota 324-8 economic deposits 310, 450 history of research 310 lithic units 312-14 Bjernoya 212, 215-17 Central Basin 66-73 Spitsbergen, NE 77, 112 Spitsbergen, NW 134-5 Spitsbergen, SW 183-7 lithostratigraphic scheme 313 palinspastics 335 sedimentary environments 318-23 structural frame 314-16 tectonic control of sedimentation 328-32 time scale 316 Cenomanian-Maastrichtian events 382-3, 386 Central basement terranes 32, 33-4 Central Basin coal 449 geomorphology 48 lithic units 48-72, 390-1 structural development 73-4, 409 structural setting 48, 344 Central Basin Terrane (CBT) 32, 35 Central East Greenland Province 38 Central Spitsbergen 73-4 Central Svalbard terranes 38

516 Central Province (Vendian) 254-5 central terrane palinspastics 268-70 central terranes (SW Spitsbergen) 199-200 Central vent volcanics (Quaternary) 423 Central West Fault Zone 48, 316 Centralwestern Spitsbergen see Spitsbergen chalcocite 189 chalcopyrite 154, 189, 197, 454 Challinor's sections 389-90, 400, 402-8 charts, hydrographic 14 Changxingian stage 351 chromium-rich dolostone 158 chronometric scale 26-7, 29, 30 chronostratic scale 25-6 Chydeniusbreen granite 113 cirripedes 379 claims 11 climate records 444-5 glacial 436 Jurassic-Cretaceous 380-1 Vendian 249 coal 37, 47, 51, 72, 73, 216, 217, 310, 363 coal fields 50, 51, 154, 389 coal mining 11,209 coccoliths 372, 379 Colesbukta well 58, 451, 452 collisional orogeny 288 compressional tectonics 38 conchostraca 294 conodonts 354 continental drift 21, 37-8 continental shelf 12 convection polygon 433 convergence, tectonic 38 Conway, Sir Martin 5, 16, 189, 340 copper minerals 454 corals 272, 327, 379 covellite 189 cover sequences 21 Bjornoya 220-2 NE Spitsbergen 112 cover terranes 32, 35-6 Cretaceous age estimation 371-2 biotas 372, 378-80 climates 380-1 coal 363, 450 history 363 igneous activity 363-5, 377-8 lithic units 52, 374-7 sedimentary environments 382-3 sedimentary sequences 386-7 stratal scheme 366 stratigraphy 366-8 structural frame 365 tectonic environments 383 time scale 371-2 cryoturbation 433 crystalline rocks see igneous also metamorphic Danskoya Basin 153 daylight 8 decoupling in transpression/transtension 410 de Geer, G. 16, 18, 340, 388, 389 deformation events 151-2 delta complexes 58, 87 desiccation cracks 434 Devonian biostratigraphy and correlation 289-91 biota 291-5 coal 450 history 289 isotopic ages 291 lithic units 135-42, 187-8, 212, 217-18

GENERAL INDEX sedimentary record 296-9 sequence of events 306-9 tectonics 299-303 time scale 289 dextral transpression/transtension, Paleogene 410-11 diamictites 21, 100, 118 Dickson Land 62 dinoflagellates 380, 394 dinosaurs 20 footprints carnosaur 55 Iguanodon 20, 58, 380 Dirksodden Nappe 129 Dirksodden Thrust 129 discontinuities (faults and unconformities) 23, 26 discovery of Svalbard 5, 11 dolerites 76, 106, 112 dolostone 31, 67, 70, 158, 163, 169-70, 265 Dragon Oil p.l.c. 94 Duvefjorden Complex 104, 108 Duvefjorden granites 106 dykes and sills 76, 106, 112, 113, 377-8 East Spitsbergen Basin 315 East Greenland aulacogen 242-3 East Spitsbergen current 8 East Svalbard terranes 38 East Svalbard Vendian Province 254 Eastern basement terranes 32-3 Eastern Svalbard Platform (ESP) 32, 75-7, 315, 344 Barentsoya 86-91 Edgeoya 86-91 Hopen 91-3 Kong Karls Land 83-6 NE Spitsbergen 77-80 SW Nordaustlandet 80-3 Tusenoyane 86-91 echinoderms fossil 279, 379 living 10 eclogite 165 economic geology coal mining 449-51 metalliferous mining 453-4 non-metaliferous mining 454 petroleum 451-2 Edgeoya 86 7 biostratigraphy 89-91 ice cover 436 igneous bodies 91 lithic units 87-8 oil exploration 93-5 Edgeoya-Barentsoya monocline 344 Ediacara biota 167 Ediacara epoch 244 Edmonds, J. M. 18 Eidembreen tectonics 34, 36, 154, 169, 266-8 Eifelian-Givetian events 308-9 Ellesmere Island 253, 255, 306 Ellesmerian (M'Clintock) orogeny 38, 270-1 ellipsoids, deformed 112 Ellsworth, L. 19 Emsian events 308 environmental regulations 12-13 Eoarchean 28 Eocene events 415-17 Eolusletta Shear Zone 130 escape tectonics 38, 277 evaporites 67, 70 exploration history 16 exploratory wells 89, 93-5, 451-2 extension 38

Fairbairn, P. E. 18 Falcon, N. L. 18 Famennian events 309 faults 172-3 boundary 316 lineaments 26 major zones 25, 27 strike-slip 38, 303, 306 dextral 173-4, 390 sinistral 204 fauna, living 10 feldspathite 31,283 ferns see pteridophytes Festningen section (Festungs Profil) 18, 49, 62, 343 Finnmarkian phase 36 fish fossil 137, 138, 291-3, 295, 353, 394 living 10 fission track analysis 398 fjords 4, 48 Fleming, W. L. S. 18 flint concretions 70 flora see plants Floraberget anticline 27 flower structure 177 flowering plants 11 fluid springs 424-6 fold and thrust front 48 fold-thrust belt 400 foraminifers 326-7, 372, 379 Forlandsundet Basin 175-6 coal 449 origin 176-7 Forlandsundet Graben 268 Paleogene 157-8, 388, 391,399, 402-9 Forlandsundet Graben Terrane (FSGT) 32, 34 formation, stratigraphic 29 Frasnian Famennian events 309 Frebold, H. 18, 363 freeze-thaw processes 433-4 frozen ground 10 fuchsite 158

galena 189, 197, 210 Garwood, E. J. 16, 18 gastropods fossil 328, 379, 394 living 10 geochemistry 102, 126-7 geographical nomenclature 5 geological maps outcrops Neogene-Quaternary 419 Paleogene 50, 389 Jurassic-Cretacous 364 Triassic 341 Carboniferous-Permian 311 Devonian 290 Silurian 273 Cambro-Ordovician 258 Proterozoic 228, 245 regions Bjornoya 211 Central Basin 47, 54, 55, 56, 58 Nordauslandet 101 Oscar II Land 58, 156 Prince Karls Forland 156 Spitsbergen NW 133, 139 Spitsbergen SW 181 geomorphology 48, 431-4 geotectonic interpretation 37 Givetian events 308-9 glacial dynamics 441-2

GENERAL INDEX glacial episodes Cenozoic 429-31 Vendian 249-51 glacial geophysics 436 glacial hydrological structure 438-41 glacial sedimentation, submarine 431 glacier flow, fast 441 glacier mass balance 444 glaciers 9, 437 glaciers and climate change 444-5 glacio-fluvial sediments 432 glaucophane schist 165, 266 gneisses 143-4, 281 gold 454 golden spike 26 graben cover sequences 37 granites 105, 106, 112-13, 143, 281-3 grasses, living 11 gravel extraction 454 gravity survey 423 Greenland 247 Carboniferous-Permian sediments 336 Devonian tectonics 306 Silurian 275 Vendian 253, 254-5 Gregory, J. W. 16, 18 Grenvillian 36, 151,453 magmatism 104, 106 grey granites, foliated 142 Griesbachian stage 351 Gripp, K. 18 group, stratigraphic 29 groups Adventdalen 52-9, 83-6, 182, 365 Akademikerbreen 119 Andr6e Land 135-8, 257, 292 Aust Torellbreen 196, 199 Billefjorden 71-3, 77, 112, 161-2, 186-7, 312, 314 Bjornoya 212, 216-18, 257 environments 318-20 Bjornoya 212, 219, 248, 257 Brennevinsfjorden 103 Buchananisen 158, 391,396 Bullbreen 162-4, 257, 272 Calypsostranda 180, 391,397 Celsiusberget 102 Comfortlessbreen 165, 257 Conglomeratfjellet 231 Deilegga 192, 193, 196 Eimfjellet 192, 193, 196, 231,239 Ferrier 167-8, 230 Finnlandveggen 124-5 Franklinsundet 102, 232 Geikie 167 Gipsdalen 66-71, 77, 82, 112, 159-61, 184-6, 214-16, 312, 314, 320-3 Gotia 248 Gotiahalvoya 100 Grampian 167, 274 Harkerbreen 122-4 Isbjornhamna 192, 194, 196, 231,239 Kapp Hansteen 103 Kapp Lyell 189, 199 Kapp Toscana 365 age 59 biostratigraphy 351 formations 59-63, 81, 87-8, 158, 182, 183, 212, 213, 340, 345, 348-50 Konglomeratfjellet 189-91, 199 Kongsvegen 166, 230 Krossfjorden 144, 144-5, 230 Lhgnesbukta 188 Magnethogda 191,196, 230, 239

Nordbukta 191, 199, 231 Oil Shales 87 Oslobreen 99-100, 116-17, 257 Peachflya 167 Planetfjella 121-2 Polarisbreen 117-18, 248, 257 Red Bay 5, 138-40, 292, 296-8, 308 Roaldtoppen 102, 232 St Jonsforden 165-6 Sassendalen 59-63, 81, 88-9, 112, 159, 183, 212, 213, 340, 345, 346-8, 351,356 Scotia 167, 248 Siktefjellet 140-2, 274, 292, 296-8 Sofiebogen 192, 195, 196, 198 Sofiekammen 192, 195, 196, 198, 257, 261 Sorkapp Land 192, 194, 196, 198, 257, 261 Tempelfjorden 63-6, 77, 81-2, 112, 159, 183-4, 212, 213-14, 312, 313, 323-4 Van Mijenfjorden 48-50, 50-1, 51-2, 155, 389 Veteranen 119-21 Werenski61dbreen 196 Ymerdalen 210, 212, 218-19 Grumanbyen coal 388 Grumantbyen 13 GSSP (global stratigraphic section and point) 26, 244, 317, 351 Guadelupian events 333-4 Gulfaksbreen anticline 27 gypsum and gypsiferous rocks 67, 310, 454 Gzelian events 331-2 Haakonian 36, 141, 151,307-8 Hageman, J. T. H. 18 half-graben 289 Halvandalen 134 Halvotenpiggen 134 Hamberg, A. 18 Hammerfest Basin 368 Hannabreen Fault (Rabotdalen-Bockfjorden Fault) 26, 149 Haraldknuttane 134 Hazen Fold Belt 36 Hecla, H.M.S. 16, 113 Hecla Hoek Complex 16, 113 basement 113-16 fabric 129 nappes 116 shear zones 129 structure 128-9 Heclahuken anticline 27 Heer, O. 16 Heer Land 55 Hellwaldfjellet 77-9 high pressure metamorphic rocks 158, 164 highland ice 10 Hinlopenstretet Islands 4, 79 Hinlopenstretet synclinorium 27 history of names of islands 7 Hoel, A. 17, 18 Holocene 443-4 geomorphology 431-4 heatflow 421 history 418 seafloor spreading 421 seismicity 421 Holtedahl, O. 17, 18, 310 Holtedahl Geosyncline 247 Hopen 91-3, 452 oil exploration 93-5 radio-station 13 Hopen Platform Terrane (HOPT) 32, 36 Horn, G. 18 Hornemantoppen Batholith 142, 150 Hornsund Fault Zone 48, 222-3

517 Hornsund High 63 Hornsund Supergroup 192, 194-5, 198, 257 Hornsund terrane (HSDT) 32, 33 Hornsundian diastrophism 192, 266 Hornsundian unconformity (HSDT) 33 hotsprings see fluid springs hunting 11 hydrocarbons see petroleum geology hyperite 76, 363 Iapetus Ocean 21,224, 255-6, 269, 271,287, 288 ice bergs 8, 442-3 ice caps 445 map 437 ice core record of climate change 445 ice cover 10, 437 ice mass dimensions 436-8 ice-ocean interaction 442 idaite 189 igneous rocks 76, 105 6, 112-13, 132-4, 142-3, 377-8 see also dykes and sills; plutonic activity; volcanic activity lguanodon 20, 58, 380 impact structure 382 indentor tectonics cf. transpression 277 Induan environments 356 Inner Hornsund Trough 316 Innuitian Orogeny 36, 306 Instrumentberget granitoid 124 International Geological Congress 20 International Polar Year 18 International Stratigraphic Lexicon 20 invertebrates (see also named groups) fossil 293-4 living 10 iron minerals 454 Isachsen, G. 16 islands map 4 isostatic rebound, glacial 431 isotopic ages 28, 29, 105-6, 113, 134, 142, 194, 235 6, 274-5, 291,393 Italia 19 jadeite 165, 266 Jarlsbergian diastrophism 192, 204-5, 266 Jarlsbergian tectonism 36 Jarlsbergian unconformity (HSDT) 33 Juvdalskampen-thrusting 53 Johanson, B. 18 Jurassic biotas 378-80 coal 363,450 climates 380-1 history 363 lithic units 52, 58, 366-8, 372-4 magrnatism 363-5, 377-8 regional sedimentation 386-7 sedimentary environment 381-2 sedimentary sequence 386 stratal scheme 366 structural frame 365 tectonic environment 383 time scale 368-71 Kaffioyra Complex 158, 175, 268 Kapp Linn6 radio station 13 Kapp Mineral 189 Kasimovian-Gzelian events 331-2 Keilhau, B. M. 16 1.9, 210, 363 Kings Bay Coalfield 154, 391 Kings Bay Kull Comp. A/S (KBKC) 13 Kinnvika syncline 27 Kluftdalen syncline 27

518 Knipovich lineament 222-3 Knipovich Ridge 48 Koch, L. 19 Kollerbreen zone 151 Kong Karls Land 83-6, 350, 436 Kong Karls Land Platform Terrane (KKPT) 32, 36 Kongsfjorden-Hansbreen Fault Zone 26, 62, 200, 305, 316 Kongsoya 83 Kontaktberget granites 105 Krossfjorden anticline 27 Krosspynten 135 Kulling, O. 18, 96-7, 99 Kungurian-Guadelupian events 333-4 Kvitbreen syncline 27 Kvitoya 97 ice cover 436

La Rkcherche 16, 189 Ladinian environments 358 Lhgoya 232 L~goya syncline 27 lamprophyres 113, 135 lands of Svalbard 7 Laponiahalv~ya granites 105 Laponiafjellet granite 105 Late Cretaceous hiatus 48 Late Permian hiatus 48 late tectonic plutons 105 latitude 8 lavas 76, 84, 85, 112, 134 lawsonite 165, 266 layered gneisses 144, 281 lead minerals 454 see also galena Lexique stratigraphique International 31 lineaments 25 lithic code 29 lithospheric contraction/expansion 43-4 lithospheric motions 38-40 lithostratigraphy v. lithic code 29 Little ice age 436 Llandeilo 28, 259, 260 Llanvirn 28, 259, 260 Lochkovian events 308 Lomfjorden Fault 53, 112 Lomfjorden (Agardhbukta) Fault Zone 26, 79, 316, 409 Lomonosovfonna pluton 113 Lomonsov conjecture 309 Lomonsov Ridge 108-9 Longyear Airport 13 Longyearbyen 11, 13 coal 388, 449 Lopingian 29, 351 Loven, S. L. 16 Lovrn syncline 27 Lovrn~yane Basin 150, 300 Lyngebreen sequence 199 Lyutkevich, Ye. M. 18 Maastrichtian events 382-3, 386 mafites 283-4 magnetostratigraphy 418, 420, 421 main fold belt, W. Nordenski61d Land 201 mammals, living 10 map projection 14 maps see geological also ice caps marble mining 454 marine influences 8 marine temperatures, Mesozoic 43 Martin, A. R. 16 Mathieson 18

GENERAL INDEX M'Clintock or Ellesmerian affinity 38, 154, 270-1, 468 Mefonntoppene rocks 199 member, stratigraphic 29 Mesoarchean 28 Mesoproterozoic 28 Mesozoic 158-9, 182-3 metamorphic complexes Hecla Hoek 128-9 Northern Nordaustlandet 104-5 NW Spitsbergen 143-4 Prins Karls Land 174 Stubendorffbreen Supergroup 131 metamorphism 174-5, 220, 280-1 microbial mats 232, 233 Middle Hornsund Terrane (MHDT) 285 migmatites of NW Spitsbergen 143-4, 281 military neutrality 11 Millarodden mining camp 189 Mimer Valley phase 309 mineralization 154, 180, 189, 197, 199, 210, 220 mineralogy 165, 361 mining see economic geology Mining Inspector 11 mining settlements 388 Miocene plateau lavas 134 Mississippian 310, 328-30 Mitrahalvoya 300 Mitrahalvoya syncline 27, 151 Mjolnir (impact) structure 382 molluscs fossil 294, 354-5 living 10 Monaco, Prince of 5, 16 Monacobreen phase/diastrophism 150 monchiquite 135 moraines 431,443-4 mosses 11 Motalafjellet 169 Moffen Island 427 Mushamna 13 Myklegardfjellet Bed 374 mylonites 283

nannofossils 379-80 Nathorst, A. G. 5 16, 18, 310, 340, 363, 388 Nathorst Land 57-8, 62, 191,201,401-2 national parks 12 nature reserves 12 Neoarchean 28 Neocomian events 382 neodigenite 189 Neogene geomorphic sequence 429 history 418 lithic units 132 magnetic anomalies 418-21 magnetostratigraphy 420 marine sedimentation 426-7 plate motions 418 shaping of Svalbard 428-9 time scale 418 uplift and erosion 427-8 volcanism 423-4 Neoproterozoic 28, 151, 189-91, 198-9 Newtontoppen granite 113 Nilsson, T. 18 nivation 433 Nobile, U. 19 Nordaustlandet Eastern Terrane (NAET) 32, 284 Nordaustlandet Platform Terrane (NAPT) 32, 35 Nordaustlandet Western Terrane (NAWT) 32-3, 284

Nordaustlandet 7 northern age determinations 106-7, 235 biotas 248, 263 Devonian thermal regime 291 history of research 96 ice cover 436 igneous bodies 105-6, 282-3 metamorphic complexes 104-5 stratal succession 96-104, 232, 257 structure 107-8 tectonostratigraphy 238 terranes 276 southwestern 80-3 Nordbreen Nappe 129 Nordbreen Thrust 129 Nordenskirld, A. E. 5, 16, 76, 96, 210, 310, 340, 388 Nordenskirldkysten 188 Nordenskirld Land 53, 58, 188-9, 200-1,400, 401 Nordenskirldkysten Terrane (NDKT) 32, 34 Nordfjorden Block/High 62, 63, 315, 344, 409 Nordhamna radio-station 13 Nordkapp anticline 27 Nordkapp granite 105 Norge, (airship) 19 Norges Svalbard og Ishavs Undersokelser 19 Norian environments 358-60 Norskebanken 153 Norske Fina 94 Norsk Polarinstitutt 11, 15, 19-20, 21, 22, 96 North Basin Terrane (NBT) 35 North East Greenland Province 37-8 North Greenland Pearya Province 37-8 Northern Platform 316 Northwest Spitsbergen Terrane (WNWT) 32, 33, 144 Northwest Wedel Jarlsberg Land Terrane, (WJNT) 32, 34 Norwegian Hydrographic Office 11 Norwegianization of names 7 Ny-]klesund 13 Ny-.~lesund coal field 154, 157, 388, 450 Ny Friesland 7 age determinations 235-6 biotas 262-3 plutonic activity 36, 112-13, 281-4, 291 stratal succession 98, 232, 257 tectonostratigraphy 237-8 topographic surfaces 111 unconformity surface 110 volcanic activity 423-4 Ny Friesland (Caledonian) Orogeny 33, 36, 192, 276-8, 306-7 Ny Friesland Eastern Terrane (NFET) 33, 284 Ny Friesland Western Terrane (NFWT) 33, 284

oblique motions 38 ocean basins 7 Odell, N. E. 18 official publications 13-15 offshore geology 152-3, 209-10 oil exploration 93-5 oil seeps 425 oil shales 340 Olav V Land 77, 110 Olav V Land Platform Terrane (OVPT) 32, 35-6 Old Red Sandstone Province 289 Olenekian environments 357 Oligocene events 417 omphacite 267 oncolites 232, 248 ooliths 58

GENERAL INDEX Ordovician biotas 260-2 correlation within Svalbard 262-4 lithic units 116-17, 162-5, 192, 212, 218-19 palinspastics 268-70 sedimentary environments 264-6 tectonic environments 266-8 tectonothermal events 270-1 time scale 259, 260 Orvin, A. K. 18, 20 Oscar II Land 155, 156 age determinations 236 biotas 264 Mesozoic 59, 62, 158-9 Paleozoic 159-65, 257 Proterozoic 165, 230 structure 168-71 tectonic setting 239, 266, 285, 399-400, 400-1 volcanics 251 Oscar II Land Terrane (OIILT) 32, 34 ostracodes 294 Oxford University expeditions 18, 77, 96 Oydandet Basin 180-1,390, 391 Palaeoaplysina build-ups 67 Palaeo-Hornsund-Bjornoya Fault Zone (PHBFZ) 344 palaeoclimates 40-3 palaeogeography 335-9, 384-5 palaeolatitudes 43 palaeomagnetic studies 43 palaeostress history 175-6 Paleoarchean 28 Paleocene events 415-16 palaeotemperatures see paleoclimate Paleogene age estimates 391-3 biota 391,393-4 coal 449-50 correlation 391-3 history of research 388-90 isotopic ages 393 lithic units Central Basin 48-52, 390-1,394-5 Central Western Spitsbergen Forlandsundet Graben 157-8, 391,395-6 Kings Bay coal field 154-7, 391,396-7 offshore 397 South Spitsbergen 180-1 regional tectonic sequence 413 structural frame 390 structure 207, 399, 409, 410 west Spitsbergen graben 402-9 western basement 399-400 tectonic sequence 410-13 thermal degradation 398 time scale 391 Paleoproterozoic 28 Paleozoic setting Oscar II Land 159-65 SW Spitsbergen 183 palinspastic reconstructions 41, 42, 268-70, 284-8, 335 Parry, W. E. 96, 310 patterned ground 432-3 Pearya 38, 253, 255, 269-70, 270-1 pegmatite 106, 142, 377 Pennsylvanian 310 see also Kasimovian-Gzelian pereletok 10 permafrost 10, 432-3 Permian biota and biostratigraphy 89-91,324-8 history 310

lithic units 312-14 Bjornoya 212, 213-15 Central Basin 63-6 Spitsbergen, NE 77, 112 Spitsbergen, NW 134-5 Spitsbergen, SW 183-7 lithostratigraphic scheme 313 palinspastics 335 sedimentary environments 323-4 structural frame 314-16 tectonic control of sedimentation 332-4 time scale 316-18 petroleum geology 93-5, 227, 451-2 Petunian 151 Phipps, C.J. 16 phosphorite and phosphates 16, 265, 340, 363, 454 pingo formation 434 place names of Svalbard 7 111, 155, 180 Planetfjella schists 129-30 plants fossil Paleogene 391,393-4 Jurassic~0.5Cretaceous 380 Triassic 355-6 Carboniferous 326 Devonian 294-6 living 11 plate tectonic motions 38-40 see also palinspastic reconstructions plateau lavas 134, 423-4 platform sequence 222 Pleistocene volcanic activity 132-3 see also Quaternary plesiosaur 86 plowmarks, glacial 431 Plurdalen-1 well 89, 93-5, 274, 451, 452 plutonic activity 105-6, 112-13, 142-3, 281-3 Polar Ocean Basin 7 political history 11 polygons 433-4 potash horizon, Cambrian 264 Pragian-Emsian events 308 pre-Vendian biotas 231-5 correlation 239-40 lithic units 117-27 palinspastics 240-3 provinces 241-2 unit names 227 terranes central 230 eastern 229 western 230-1 Precambrian chronometric scale 27 hydrocarbons 227 isotopic ages 235-6 time scales 229 precipitation 8 Pretender Fault 62, 150 Pretender Lineament 151,344 Princess Alice (yacht) 16 Prins Karls Forland 155, 156 biota 264 lithic units 166-8 structure 171-5 tectonic setting 268, 285, 399 volcanics 251 Prins Karls Forland Terrane (PKFT) 32, 34 prokaryotes 233 Proterozoic Nathorstland 189-94 Nordenskirld Land 188-9

519 Oscar II Land 165-6 Sorkapp Land 197-9 Wedel Jarlsberg Land 189-94 see also pre-Vendian also Vendian protists multicellur 234-5 unicellular 233-4 proto-basement 236-7 deformation 205, 305 terranes and subterranes East 237-8 North Central 238-9 South Central 239 West 239 protolith 31 provinces 37-8 provinces, tectono-stratigraphic 25 pteridophytes fossil 394 living 11 Pyramiden 13 pyrite 189, 197 pyrrhotite 197

Quaternary geomorphic sequence 429 history 418 marine sedimentation 426-7 time scale 418 uplift and erosion 427-8 volcanism 423-4 Queen Elizabeth Islands 360

Rabotdalen-Bockfjorden Fault 149 Raddedalen-I well 93-5, 89, 274, 451, 452 raised beaches 432, 434 rank, stratigraphic 3 I Raudberget granites 113 Raudfjorden Basin 149 Raudfjorden Fault 150, 300 Raudfjorden Fault Zone 26, 305 Ravn, J. P. J. 18 reef build-ups 310 Rekvika Nappe 129 Rekvika Thrust 124, 129 reservoir rocks 310, 363 Rhaetian 351,356, 360-1,381 Richarddalen Complex 145, 149, 230 age determinations 236 tectonostratigraphy 238-9 tectonothermal events 291 Richarddalen Orogeny 33 Richardvatnet anticline 27 Rijpdalen granites 104, 106 Rijpfjorden granites I06 Rinkian 36 rock glaciers 432 Rozycki, S. Z. 18

Sabine, Sir Edward 16 Sabine Land 61-2 sabkhas 71 St Jonsfjorden Trough 315, 344 Salterella 262 Sandford, K. 18 Save Srderbergh, G. 18 scaphopods 379 scientific serials, official 15 Scoresby, W. 16 Scotiadalen Fault Zone 172

520 Scottish Spitsbergen Syndicate 18 Scottish Vendian 253 Scythian environments 356-7 sea level changes 7, 434-5 sea ice 8-10 sector boundary 11-12 sectors for description in this work 23 seismic stratigraphy 421 sequence stratigraphy 37 serpentine 164, 267 settlements 4, 13 Shell Oil Company 20 Sigurdfjellet volcanic core 132 sills and dykes 106, 112, 113, 377-8 Silurian biostratigraphic correlation 272-4 igneous activity 281-3 isotopic ages 274-5 metamorphism 280-1 palinspastics 284-8 petrogenesis 280 sedimentation and tectonics 275 tectogenesis 275-80 tectonic vergences 280 time scale 272 Sjdanovfjellet faunas 262 Sjubrebanken 152-3 Skrifter om Svalbards og Ishavet 18

SKS, Committee on the stratigraphy of Svalbard 31 Slakli faunas 261-2 Smeerenburgian (Caledonian) Orogeny 33, 36, 142, 151,307 Snofjella syncline 27 snow cover 10 soil polygons 434 solid geology see geological maps Sorkapp Basin 224 Sorkapp Land biotas 260 lithic units 55-7, 63, 182-3, 230, 231,257 structure 205-8 tectonic setting 286, 400, 402 volcanic rocks 252 Sorkapp-Hornsund High 316 Sorlifjellet 134 source rocks 310 South Eastern Svalbard Terrane 285 Southern basement terrane 32 Southern Basin Terrane (SBT) 35 Southwest Basin 344 Southwest Wedel Jarlsberg Land Terrane (WJST) 32, 34 Sparreneset syncline 27 sphalerite 189, 197 Spitsbergen tectogenesis 169-71 Spitsbergen 436 basins classified 315 central basin coal 449 geomorphology 48 lithic units 48-72, 390-1 structural development 73-4, 409 structural setting 48, 344 central western lithic units 154-68 structure 168-77 northeastern cover rocks 112 geological setting 110-12 lithic units 77, 116-27 metamorphic rocks 113-16, 128-31 plutonic rocks 112-13 tectonic environment 266

GENERAL INDEX northwestern cover rocks 134-5 fault zones 305 offshore geology 152-3, 410 Paleozoic units 135-45, 275, 278-9 Proterozoic 230 structure 145-52 volcanic rocks 132-4, 423 southern and southwestern biostratigraphic correlation 260-2 lithic units 180-99, 230 structure 200-7 tectonism 266, 279-80 western 275 Spitsbergen Basin 35-6, 315, 136, 344 Spitsbergen Treaty 5, 11-13, 18 Spitsbergian (West Spitsbergen Orogeny) 5, 7, 50, 151-2, 154, 169-70, 388 springs with gas, Holocene 424 Stappen High 224 Stensi6, A. E. 18 Stepanov, D. L. 18 stone circles 433 stone uplift 433 stone walking 433 Storoya 97, 107 stratigraphic conventions and names 31 strike-slip motions 38, 303, 306 dextral 173-4, 390 sinistral 204 stromatolites 58, 248, 232, 379 structural elements of Svalbard 25, 27, 128 Sturtian 450 submarine outcrop studies 76, 222-4 subsidence 43-4 subterranes 32 6 suffixes 7 sulphates see anhydrite; barite; gypsum sulphide minerals 179, 180, 189, 197, 201,453-4 summit envelope 8 supergroup, stratigraphic 29 supergroups Bfinsow Land Supergroup 48, 63-73, 134-5, 159, 183-7, 257, 312-14 Hinlopenstretet Supergroup 99-100, ! 16-18,

thermal contraction 434 thorium 454 tillites 18, 100, 118, 188 time scales and time frame 25-9 Tithonian stage 348-9 Toarcian events 381 topography and topographic maps 6, 7-8, 14, 111, 155, 180

Torell, D. M. 5 16, 388 Torell Land 55, 57 Torellian 34, 36, 192 tourism 12 trace fossils 65, 137, 138, 380, 394 transpression 38, 50-1, 168, 303 transpressive shear 130-1 transtension 50-1,303 transverse Mercator projection 14 Treaty of S6vres (1920) 5 tree trunks, fossil 84 Triassic biostratigraphic correlation 89, 351-3 biota 353-6 climates 362 economic deposits 340, 450 environments 356-61 history of research 340 initial boundary 351 lithic units 59, 77, 112, 212-13 magneto-stratigraphic correlation 353 palaeolatitudes 362 regional sedimentation 362 rock units 344 50 structural frame 343-4 tectonic framework 361-2 time scale 350-1 trilobites 328 Trollfjorden-Komagev Fault 287 Trygghamna-Lappdalen 170 1 Tunheim 13 turbidites 87 Tusenoyane 4, 86-7 biostratigraphy 89-91 igneous bodies 91 lithic units 87-9 Tyrrell, G. W. 18

257

Liefde Bay Supergroup 135-42, 292 Lomfjorden Supergroup 118-21,232 Murchison Bay Supergroup 100-3, 232 Nordenski61d Land Supergroup 47 Stubendorffbreen Supergroup 121-8, 131 surging, glacier 441 Sutorfjella conglomerate 34, 167, 268, 274 Svalbardian events 18, 33, 36, 151,309 Svalbardian stage 318 Sveagruva 13 Sveagruva coal 388 Sveanor syncline 27 Svenskoya 82, 83 Sverdrup, H. V. 20 Sverrefjellet volcanic cone 132 talite 10 talus cores 432 tectonic map 182 tectonic synthesis 175, 176-7, 177-8 tectono-stratigraphic sequences 31 temperatures, summer and winter 8 terrane, composite 38 terranes, allochthonous 21, 37-8 terranes, descriptive 32-6 Terre Glac6e Russe 77 Tertiary Basin see Central Basin thematic maps 15

unconformities 25 underplating 288 uplift 44, 427-8,431 uplift stones 433 Upper Atlantic Layer 8 uranium 454 Varanger Epoch 21,244 sequence 199 tillites 21, 188 Vegardbreen thrust 171 Vendian biostratigraphy 246 biota 248 climates 249 correlation 246-8 environments 249 glacial 21,249-51 tectonic 252 volcanic 251-2 international correlation 252-4 lithic units 212, 219 palinspastics 254-6 paleolatitude 256 time scale 244-6 vergence, Caledonian 219 vergence, tectonic 172

GENERAL INDEX Versailles Treaty 11, 16 vertebrates, fossil 353-4, 379, 380 see also dinosaurs; fish Vestbakken volcanic province 223 Vestfonna 96 Vestg6tabreen Complex 164-5, 231,257 Veteranen Line 26 Veteranen syncline 27 Viking exploration 5 Vimsodden-Isbjornhamna Terrane 192 Vimsodden-Kosibapasset Fault (VKF) 194 Visean events 328-30 vitrinite reflectance 175, 398 Vogt, T. 18 volcanic activity Mesozoic 365 Neogene 132, 134, 423-4 Pleistocene 132-4 Tertiary 223 Vendian 251-2

weather 8 Wedel Jarlsberg Land 195-6 age determination 236 lithic units 62-3, 189-91, 195-6, 230, 231,257 structure 201-5 tectonics 239, 279, 286, 401-2 terranes (WJNT; WJST) 32 volcanic rocks 251-2 wells, exploratory 93-5, 451-2 Werenski61dian 36, 192 West Spitsbergen Basin 315 West Spitsbergen current 8 West Spitsbergen Fault Zone 48, 316 West Spitsbergen Orogen 48, 177-8, 389, 403-8, 453 northern segment 177-8 Wedel Jarlsberg Land 201-5 western zone 63 West Spitsbergen Orogeny 5, 7, 50, 151-2, 154, 169-70, 388

521 West Svalbard terranes 38 Western basement terranes 32, 34 Western Basin 344 Western Basin Terrane (WBT) 32, 35 Western Northwest Terrane 144, 150-1,285 western terranes, SW Spitsbergen 199 whaling 11, 13 Wilhelmoya 4, 75, 77-9 Wilkins 19 Wiman, C. 18 Yermak Plateau 152, 388 Zechstein 310 zircon ages 36, 105, 114, 124, 151,220, 235,236, 398 zinc 454