Sedimentation and Tectonics in Rift Basins

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Sedimentation and Tectonics in Rift Basins

Red Sea:- Gulf of Aden

Edited by

Bruce H. Purser Emeritus Professor of Sedimentology

Universite de Paris Sud France

and

Dan W. J. Bosence Professor of Carbonate Sedimentology

Royal Holloway University of London

UK

Much of the research presented in this book was supported by the SCiENCE Programme of the European Community.

m SPRINGER-SCIENCE+BUSINESS MEDIA, B.V.

First edition 1998

© 1998 Springer Science+Business Media Dordrecht OriginalIy published by Chapman & HalI in 1998 Softcover reprint ofthe hardcover lst edition 1998

Thomson Science is a division of International Thomson Publishing

Typeset in 1O/12pt Times by Scientific Publishing Services (P) Ltd, Chennai, India

ISBN 978-94-010-6068-4 ISBN 978-94-011-4930-3 (eBook) DOI 10.1007/978-94-011-4930-3

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Contents

Contributors Preface

SECTION A. INTRODUCTION

A 1. Organization and scientific contributions in sedimentation and tectonics of rift basins: Red Sea-Gulf of Aden B.H. Purser and D. W.J. Bosence

x XV

3

Significance of the Red Sea and Gulf of Aden as a natural laboratory for rift basin studies, 3

The organization of this volume, 4 Some major contributions of this volume, 4

A2. Stratigraphic and sedimentological models of rift basins D. W.J. Bosence

Introduction, 9 Rift basin models, 10 Stratigraphic response to different geotectonic

rift-basin models, 11

9

Application of rift models to the Gulf of Suez, Red Sea and Gulf of Aden, 14

Rift sub-basins and facies models, 18 Sequence stratigraphic concepts in rift basins, 21 Conclusions, 25

SECTION B. GEOPHYSICAL, MAGMATIC AND STRUCTURAL FRAMEWORK

B1. Geophysical studies on early tectonic controls on Red Sea rifting, opening and sedimentation R. Rihm and C.H. Henke 27

Introduction, 29 Crustal domains of the Red Sea inferred from

seismic data, 30 Gravity field of the Red Sea, 37 Magnetic trends in the southeru and central Red

Sea and onshore Yemen, 41 Geometry of Red Sea margins, 41 Plate tectonic reconstruction of the Red Sea, 45 Discussion and conclusions, 48

B2. Pre-, syn- and post-rift volcanism on the south­western margin of the Arabian plate G. Chazot, M.A. Menzies and J. Baker 50

Introduction, 50 Chronology of magmatism, 50 Arabian plate magmatism, 53 Conclusions, 55

B3. Tectonic and sedimentary evolution of the eastern Gulf of Aden continental margins: new structural and stratigraphic data from Somalia and Yemen P.L. Fantozzi and M. Sgavetti 56

Introduction, 56 General geologic setting, 57 Stratigraphic framework of the study areas, 59 Tectonic setting of the areas, 61 Discussion, 73 Conclusions, 74

VI Contents

84. Structure, sedimentation, and basin dynamics during rifting of the Gulf of Suez and north-western Red Sea W. Bosworth, P. Crevello, R.D. Winn Jr. and J. Steinmetz 77

Introduction, 78 Regional setting, 78 Fault block evolution and stratigraphic

development, 82 Conclusions, 90

85. Rift development in the Gulf of Suez and the north-western Red Sea: structural aspects and related sedimentary processes C. Montenat, P. Ott d'Estevou, J.-J. Jarrige and J.-P. Richert

General setting, 97 Structural framework, 102 Tectonic evolution, 104

97

Structural stages and sedimentary processes, 107 Initial doming versus uplift of the rift

shoulders, 114 Short comparisons with other tectono-sedimentary

rift sequences, 115 Conclusion, 116

SECTION C. EARLY RIFT SEDIMENTATION AND TECTONICS

C1. Pre-rift doming, peneplanation or subsidence in the southern Red Sea? Evidence from the Medj-zir Formation (Tawilah Group) of western Yemen A.-K. Al-Subbary, G.J. Nichols, D. W.J. Bosence and M. Al-Kadasi 119

Introduction, 119 Definition and distribution of uppermost Tawilah

Group sediments, western Yemen, 121 Discussion, 130 Conclusions, 133

C2. Sedimentary evolution of early rift troughs on the central Red Sea margin, Jeddah, Saudi Arabia M.A. Abou Ouf and A.M. Gheith 135

Introduction, 135 Geological setting of the Usfan and Shumaysi

Formations, 136 Methods, 139 The Usfan Formation, 139 The Shumaysi Formation, 140 Discussion, 141 Conclusions, 144

C3. The sedimentary record of the initial stages of Oligo-Miocene rifting in the Gulf of Suez and the northern Red Sea C. Montenat, F. Orszag-Sperber, J.-c. Plaziat and B.B. Purser 146

Introduction, 146 Geodynamic framework, 146 Early rift sediments, 147 Climate, 154 Synsedimentary deformation related

to early rifting, 155 Evolution of relief during early rifting, 156 Asymmetry of rift initiation in space and time, 157 Discussion and conclusions, 160

SECTION D. SYN-RIFT SEDIMENTATION AND TECTONICS

D1. Rift-related sedimentation and stratigraphy, southern Yemen (Gulf of Aden) F. Watchorn, G.J. Nichols and D.W.J. Bosence 165

Introduction, 165 Previous work, 168 Regional stratigraphy, 168 Tectonic architecture, 168 Pre-rift stratigraphy, 171 Rift sediments, 172 Discussion, 185 Conclusions, 189 Appendix, 189

02. Miocene isolated platform and shallow-shelf carbonates in the Red Sea coastal plain, north-east Sudan J.H. Schroeder, R. Toleikis, H. Wunderlich and H. Kuhnett 190

Introduction, 190 Previous work, 191 Location of outcrops and geological

framework, 192 Field and laboratory work, 193 Facies analysis, 193 Biostratigraphy, 201 Discussion, 204 Conclusions, 210

03. Stratigraphy of the Egyptian syn-rift deposits: correlations between axial and peripheral sequences of the north-western Red Sea and Gulf of Suez and their relations with tectonics and eustacy J.-C. Plaziat, C. Montenat, P. Barrier, M.-C. Janin, F. Orszag-Sperber and E. Philobbos 211

Introduction, 211 Overview of stratigraphic evolution, 211 The early-rift strata, 212 The open-marine syn-rift strata (Group B), 215 The outcropping evaporites series (Group C2), 219 The post-evaporitic unit (Group D), 220 Conclusion, 222

04. Extensional tectonics and sedimentation, eastern Gulf of Suez, Egypt K.R. McClay, G.J. Nichols, S.M. Khalil, M. Darwish and W. Bosworth

Introduction, 223 Tectonic setting and geological history

of the Gulf of Suez, 224 Stratigraphy of the eastern margin of the

Gulf of Suez, 231 Tectono-stratigraphic evolution of the eastern

margin of the Gulf of Suez, 237

05. Carbonate and siliciclastic sedimentation in an active tectonic setting: Miocene of the north-western Red Sea rift, Egypt B.H. Purser, P. Barrier, C. Montenat, F. Orszag-Sperber, P. Ott d'Estevou, J.-c. Plaziat and E. Philobbos

223

239

Contents vii

Introduction, 240 The Middle Miocene syn-rift platforms

of the north-western Red Sea, 241 Discussion, 263 Conclusions, 270

06. The tectono-sedimentary evolution of a rift margin carbonate platform: Abu Shaar, Gulf of Suez, Egypt N.E. Cross, B.H. Purser and D. W.J. Bosence 271

Introduction, 271 Structural setting, 274 Regional syn-rift stratigraphy, 276 Depositional sequences, facies and

environments, 277 Discussion, 291 Conclusions, 295

D7. Miocene coral reefs and reef corals of the south­western Gulf of Suez and north-western Red Sea: distribution, diversity and regional environmental control C. Perrin, J.-c. Plaziat and B.R.· Rosen 296

Introduction, 296 Age and regional setting of reef development, 297 Occurrence, geometry and development

of coral reefs, 298 Discussion, 312 Conclusions, 318

08. Miocene peri platform slope sedimentation in the north-western Red Sea rift, Egypt B.H. Purser and J.-c. Plaziat

Introduction, 320

320

The mid-Miocene slopes and their sediments, 323 Specific slope features and sedimentary

dynamics, 333 Discussion and conclusions, 343

D9. The tectonic significance of seismic sedimentary deformations within the syn- and post-rift deposits of the north-western (Egyptian) Red Sea coast and Gulf of Suez J.-c. Plaziat and B.H. Purser

Introduction, 347 Deformation processes and morpho-structural

influence on seismite types, 349 Chronological distribution of seismicity

in the syn-rift series, 351

347

Vlll Contents

Discussion: relationships between seismites and tectonic history, 365

Conclusion, 366

SECTION E. SYN-RIFT CARBONATE DIAGENESIS

El. Syn-rift diagenesis of the Middle Miocene carbonate platforms on the north-western Red Sea coast, Egypt B.H. Purser 369

Introduction, 369 The principal diagenetic attributes of the mid­

Miocene carbonates, 371 Discussion, 386 Conclusion, 387

E2. The dolomitization and post-dolomite diagenesis of Miocene platform carbonates: Abu Shaar, Gulf of Suez, Egypt N. Clegg, G. Harwood and A. Kendall 390

Geological setting, 390 Methods, 391 Diagenesis, 392 Conclusions, 402

SECTION F. EVAPORITES AND SALT TECTONICS

Fl. A review of the evaporites of the Red Sea-Gulf of Suez rift F. Orszag-Sperher, G. Harwood, A. Kendall and B.H. Purser 409

Introduction, 409 The temporal distribution of the evaporites

(Miocene-Recent), 410 Age of the Miocene evaporite formations, 411 Miocene evaporitic facies and sedimentation, 414 Relationships between Miocene evaporite

sedimentation and rift structure, 418 Evaporite tectonics, 422 Post-Miocene evaporites, 423 Discussion and conclusions, 425

F2. Post-Miocene sedimentation and rift dynamics in the southern Gulf of Suez and northern Red Sea F. Orszag-Sperher, B.H. Purser, M. Rioual and I.-C. Plaziat 427

Introduction, 427 'Pliocene' sedimentation and tectonics, 429 Discussion and conclusions, 444

F3. Salt domes and their control on basin margin sedimentation: a case study from the Tihama Plain, Yemen D. W.J. Bosence, M.H. Al-Aawah, I. Davison, B.R. Rosen, C. Vita-Finzi and E. Whitaker 448

Introduction, 448 Geological setting of south-eastern Red Sea salt

domes, 449 Sedimentology of Salif cover rocks (Kamaran

Limestone and Al Milh Sandstone), 457 Discussion concerning the role of salt diapirism

in controlling margin sedimentary evolution, 460

Conclusions and implications, 462 Appendix, 463

SECTION G. POST-RIFT AXIAL SEDIMENTS AND GEOCHEMISTRY

Gl. Axial sedimentation of the Red Sea transitional region (22°_25° N): pelagic, gravity flow and sapropel deposition during the late Quaternary M. Taviani 467

Introduction, 467 Geological and hydrological setting of the study

area, 468 Axial zone sediments, 469 Discussion, 476

G2. Sedimentation, organic chemistry and diagenesis of cores from the axial zone of the southern Red Sea: relationships to rift dynamics and climate P. Hofmann, L. Schwark, T. Brachert, D. Badaut, M. Riviere and B.H. Purser 479

Introduction, 479 The mineralogical and textural properties

of the axial zone of the Red Sea, 481 Organic geochemical properties and origins

of sapropels, 491 Diagenetic properties and origin

of lithified crusts, 497 Comparisons with other areas of the Red Sea

and Gulf of Aden, 50 I

Discussion and conclusions, 502 Appendix: analytic methods, 503

G3. Metalliferous sedimentation in the Atlantis II Deep: a geochemical insight G. Blanc, P. Anschutz and M.-C. Pierret 505

Introduction, 506 Mineralogy of the lithological units, 507 Geochemical history of the Atlantis II Deep, 517

SECTION H. POST-RIFT COASTAL SEDIMENTS, REEFS AND GEOMORPHOLOGY

H 1. Present-day sedimentation on the carbonate platform of the Dahlak Islands, Eritrea F. Carbone, R. Matteucci and A. Angelucci 523

Introduction, 524 Environmental parameters, 524 General geological setting, 524 Local structural pattern, 526 Sedimentary patterns, 529 Discussion and conclusions, 533

H2. Quaternary marine and continental sedimentation in the northern Red Sea and Gulf of Suez (Egyptian coast): influences of rift tectonics, climatic changes and sea-level fluctuations J.-c. Plaziat, F. Baltzer, A. Choukri, O. Conchon, P. Freytet, F. Orszag-Sperber, A. Raguideau and J.-L. Reyss 537

Introduction, 537 Geographic and climatic context, 538 Chronology of Quaternary deposits and problems

of dating, 539 Regional synthesis and discussion, 563 Conclusion, 572

Contents lX

H3. Post-Miocene reef faunas of the Red Sea: glacio-eustatic controls M. Taviani

Introduction, 574 Late Quaternary faunal turnovers, 579 Conclusions, 582

H4. Modern Red Sea coral reefs: a review of their morphologies and zonation

574

w.-c. Dullo and L. Montaggioni 583

Introduction, 583 Siliciclastic control, 584 Modern reefs of the Aqaba-Eilat Gulf areas, 585 Tectonic control, 587 Salt diapir control on reefs, 592 Sea-level control and reef terraces, 593 Conclusions, 594

H5. Tectonic geomorphology and rates of crustal processes along the Red Sea margin, north-west Yemen I. Davison, M.R. Tatnell, L.A. Owen, G. Jenkins and J. Baker 595

Introduction, 595 Geologic history, 596 Stratigraphy, 598 Geomorphology of north-west Yemen, 599 Rates of crustal processes, 605 Discussion, 610 Conclusions, 611

References Index

613 653

Contributors

M.A. Abou our Dept of Marine Geology Faculty of Marine Science King Abdulaziz University Jeddah Saudi Arabia

M.H. AI-Aawah Dept of Geology University of Sana'a Sana'a Republic of Yemen

M. AI-Kadasi Dept of Geology University of Sana'a Sana'a Republic of Yemen

A.K. AI-Subbary Dept of Geology Royal Holloway, University of London Egham Surrey TW20 OEX UK

A. Angelucci Dipartimento di Scienze della Terra Universita 'La Sapienza' P A Moro 5 00185 Rome Italy

P. Anschutz Departement de Geologie et Oceanographie (DGO) URA CNRS 197 Universite Bordeaux 1 Avenue des Facultes 33405 Talence Cedex France

D. Badaut Laboratoire de Geologie Museum National d'Histoire Naturelle Paris France

J. Baker Dept of Geology Royal Holloway, University of London Egham Surrey TW20 OEX UK

F. Baltzer Departement des Sciences de la Terre URA 723 Batiment 504 Universite de Paris Sud 91405 Orsay Cedex France

P. Barrier Institut Geologique Albert de Lapperent (IGAL) Institut Poly technique Saint-Louis 13 Boulevard de l'Hautil F 95092 Cergy-Pontoise Cedex France

G. Blanc Departement de Geologie et Oceanographie (DGO) URA CNRS 197 Universite Bordeaux 1 Avenue des Facultes 33405 Talence Cedex France

D.W.J. Bosenee Dept of Geology Royal Holloway, University of London Egham Surrey TW20 OEX UK

W. Bosworth c/o Marathon Oil Company Cairo Office PO Box 1228 Houston TX 77251-1228 USA

T. Braehert Institut fur Geowissenschaften UniversiUit Mainz Germany

F. Carbone c/o Dipartimento di Scienze della Terra Universita 'La Sapienza' P A Moro 5 00185 Rome Italy

G. Chazot Sciences de la Terre Ecole Normale Superieure 69364 Lyon Cedex 07 France

A. Choukri Sciences de la Terre Ecole Normale Superieure 69364 Lyon Cedex 07 France

N. Clegg School of Environmental Sciences University of East Anglia Norwich NR4 7TJ UK

O. Conchon Departement des Sciences de la Terre URA 723 Batiment 504 Universite de Paris Sud 91405 Orsay Cedex France

P. CreveDo Dept of Petroleum Geosciences University of Brunei Bandar 2028 Darassalam Brunei

N.E. Cross Badley Ashton Associates Winceby Horncastle Lincolnshire LN9 6PB UK

M. Darwish Geology Department Faculty of Science Cairo University Cairo Egypt

1. Davison Dept of Geology

Contributors Xl

Royal Holloway, University of London Egham Surrey TW20 OEX UK

W.-C. DuDo GEOMAR Research Centre for Marine Geosciences Wischhofstrasse 1-3 Geb 4 D-24148 Kiel Germany

P.L. Fantozzi Dept of Earth Sciences University of Siena Via delle Cerchia 3 53100 Siena Italy

P. Freytet Departement des Sciences de la Terre URA 723 Batiment 504 Universite de Paris Sud 91405 Orsay Cedex France

A.M. Gheith Dept of Marine Geology Faculty of Marine Science King Abdulaziz University Jeddah Saudi Arabia

C.H. Henke Terrasys Eiffestrasse 78 20537 Hamburg Germany

Xli Contributors

P. Hofmann Geologisches Institut Universitat Kaln Germany

M.-C. Janin Universite Pierre et Marie Curie Laboratoire de Micropaleontologie CNRS 4 place Jussieu 75252 Paris Cedex 05 France

J.J. Jarrige Elf-Aqui taine CSTJF A venue Larribau 64108 Pau Cedex France

G. Jenkins Dept of Earth Sciences University of Wales PO Box 914 Cardiff CF1 3YE UK

A. Kendall School of Environmental Sciences University of East Anglia Norwich NR4 7TJ UK

S.M. Khalil Dept of Geology Royal Holloway, University of London Egham Surrey TW20 OEX UK

H. Kuhnett Universitat Bremen Fachbereich 5 Geowissenschaften Postfach 330 440 28334 Bremen Germany

R. Matteucci Dipartimento di Scienze della Terra Universita 'La Sapienza' P A Moro 5 00185 Rome Italy

K.R. McClay Dept of Geology Royal Holloway, University of London Egham Surrey TW20 OEX UK

M.A. Menzies Dept of Geology Royal Holloway, University of London Egham Surrey TW20 OEX UK

L. Montaggioni URA 1208 CNRS Universite de Provence Centre de Sedimentologie et Paleontologie 3 Place V Hugo F-13331 Marseille Cedex 3 France

C. Montenat Institut Geologique Albert de Lapperent (IGAL) Institut Poly technique Saint-Louis 13 Boulevard de l'Hautil F 95092 Cergy-Pontoise Cedex France

G.J. Nichols Dept of Geology Royal Holloway, University of London Egham Surrey TW20 OEX UK

F.Orszag-Sperber Departement des Sciences de la Terre URA 723 Biitiment 504 Universite de Paris Sud 91405 Orsay Cedex France

P. Ott d'Estevou Elf-Aquitaine CSTJF Avenue Larribau 64108 Pau Cedex France

L.A. Owen Dept of Earth Sciences University of California Riverside California 92521 USA

c. Perrin Laboratoire de Paleontologie Museum National d'HistoireNaturelle 8 rue Buffon 75005 Paris France

E. Philobbos Dept of Geology University of Assiut Faculty of Sciences 71516 Assiut Egypt

M.-C. Pierret Centre de Geochimie de la Surface (CGS) UPR 6251 Universite Louis Pasteur 1 Rue Blessig 67084 Strasbourg France

J .-C. Plaziat Departement de Sciences de la Terre Batiment 504 Universite de Paris Sud 91405 Orsay Cedex France

B.R. Purser Laboratoire de Petrologie et Pale ontologie Batiment 504 Universite de Paris Sud 91405 Orsay Cedex France

A. Raguideau Departement des Sciences de la Terre URA 723 Batiment 504 Universite de Paris Sud 91405 Orsay Cedex France

J.-L. Reyss Centre des Faibles Radioactivites Laboratoire mixte CNRS/CEA Domaine CNRS F-91198 Gif-sur-Yvette Cedex France

R. Rihm Geomar Foschungszentrum fUr Marine Geowissenschaften Wischhofstrasse 1-3 24148 Kiel Germany

M. Rioual Department des Sciences de la Terre URA 723 Batiment 504 Universite de Paris Sud 91405 Orsay Cedex France

M. Riviere

Contributors xiii

Laboratoire de Petrologie et Paleontologie Batiment 504 Universite de Paris Sud 91405 Orsay Cedex France

B.R. Rosen Dept of Palaeontology Natural History Museum Cromwell Road London SW7 5BD UK

J .R. Schroeder Technische Universitat Berlin Institut fUr Angewandte Geowissenschaften II Sekr. EB 10 Ernst-Reuter Platz 1 01587 Berlin Germany

L. Schwark Geologisches Institut Universitat Kaln Germany

M. Sgavetti Institute of Geology University of Parma Viale delle Scienze 78 43100 Parma Italy

J. Steinmetz Montana Bureau of Mines & Geology Butte Montana 59701-8997 USA

M.R. Tatnell Dept of Geology Royal Holloway, University of London Egham Surrey TW20 OEX UK

xiv Contributors

M. Taviani Instituto di Geologia Marina CNR Via Go betti 101 40129 Bologna Italy

R. Toleikis Technische UniversiHit Berlin Institut fUr Angewandte Geowissenschaften II Sekr. EB 10 Ernst-Reuter Platz 1 01587 Berlin Germany

C. Vita-Finzi Dept of Geological Sciences University College London Gower Street London WCIE 6BT UK

F. Watchorn Dept of Geology Royal Holloway, University of London Egham Surrey TW20 OEX UK

E. Whitaker Dept of Geology Royal Holloway, University of London Egham Surrey TW20 OEX UK

R.D. Winn Jr. Dept of Geology University of Papua New Guinea PO Box 414 University NCD Papua New Guinea

H. Wunderlich Technische UniversiHit Berlin Institut fUr Angewandte Geowissenschaften II Sekr. EB 10 Ernst-Reuter Platz 1 01587 Berlin Germany

Preface

The Red Sea-Gulf of Aden is an active maritime rift system which is unique in the world. Interest in rifts is considerable because they are vital in terms of under­standing the fundamental mechanisms of plate move­ments and their related seismicity, and because the sedimentary basins which result can be important in terms of hydrocarbon and metalliferous potential. Furthermore, the Red Sea-Gulf of Aden rift system covers about 200 of latitude and therefore is also a favourable site for the study of past climatic changes through a particularly rich sedimentary record.

In recent years, the European Community pro­gramme SCIENCE (Stimulation of the Cooperation and Interchange among European Scientists) has financed several research groups working in the im­portant field of rifting. Thus, from 1988 to 1994, four rift projects were implemented which strengthened the collaboration between the research teams, developed competences, and reinforced the mobility of researchers, thus contributing to the understanding of the Red Sea­Gulf of Aden rift system.

This volume, comprising eight sections, presents results of extensive research carried out by 62 scientists based mainly in different European and Middle East countries. It represents a valuable reference for all potential users (students, geoscientists and climatolo­gists), since it covers most aspects of rifting mechanisms, starting with the geophysical, magmatic and structural framework of rifts, through early rift sedimentation and tectonics, syn-rift sedimentation, diagenesis of rift

sediments and, finally, post-rift sedimentation and geochemistry. The originality of this volume is that, for the first time, rift evolution is treated from many angles. The compilation includes items of varying scale ranging from 'broad-brush' plate tectonics to micro­scopic sedimentary components, all relating to a common factor - rift dynamics and evolution. This compilation is also based both on classical onshore field studies and on offshore oceanographic methods, giving a balanced picture of rift dynamics and its sedimentary expression. It also discusses both the superficial and deep-crustal expressions of a given set of geological events.

Finally, the Red Sea-Gulf of Aden volume represents a genuine step forward in the knowledge of the sedimentary processes within rift systems. Although discussed mainly in terms of a specific rift-type basin, the results may be readily extrapolated to other parts of the world and thus be utilized as a comparative model for the better understanding of rift-type basins in general. In particular, this volume provides a unique source of new data readily accessible to all researchers working on the plate tectonics of new ocean basins and the economically important sedimentary fill of rifts.

Gilles Ollier European Commission

Directorate General XII Science, Research and Development