Geodynamics of Rifting (eBook)

Front Cover 1
Geodynamics of Rifting 4
Copyright Page 5
Table of Contents 6
Preface 8
TECTONOPHYSICS—Volume 208—No. 1–3 10
Chapter 1. The Oslo Rift: a review 10
Introduction 10
Geology 12
Origin and evolution of the igneous rocks 16
Geophysical surveys and results 18
Acknowledgements 23
References 24
Chapter 2. A stretching model for the Oslo Rift 28
Introduction 28
Pre-rift geological setting 30
Oslo Rift observations and modelling parameters
Modelling: theory and results 36
Isostasy 36
Discussion 39
Conclusions 42
Acknowledgements 42
References 42
Chapter 3. Early magmatic phase in the Oslo Rift and its related stress regime 46
Introduction 46
The older complex of sills and dykes 48
Rb–Sr and Sm–Nd isotopic relationship 51
Discussion 56
Conclusions 60
Acknowledgements 61
References 61
Chapter 4. North Sea rift system 64
Introduction 64
Pre-rift history of North Sea area 67
Triassic–Early Jurassic rifting stage 69
Mid-Jurassic thermal dome 72
Late Jurassic-Early Cretaceous rifting stage 72
Late Cretaceous–Paleocene late-rifting stage 74
Eocene–Recent post-rifting stage 80
Crustal configuration and amount of upper crustal extension 80
Geodynamic considerations 81
Conclusions 83
Acknowledgments 83
References 83
Chapter 5. Basaltic magmatism in the North Sea and its relationship to lithospheric extension 86
Introduction 86
Mesozoic magmatism in the North Sea 87
Melting asthenosphere during rifting in the North Sea 90
Mixing asthenospheric and lithospheric components 93
Conclusions 95
Acknowledgements 96
Appendix: Chemical analyses 96
References 98
Chapter 6. European Cenozoic rift system 100
Introduction 100
Tectonic framework 101
Evolution of the rift system 103
Crustal and lithospheric configuration 110
Geodynamic considerations 113
Conclusions 116
Acknowledgments 117
References 117
Chapter 7. Lithospheric cross sections of the European Cenozoic rift system 122
Introduction 122
European Cenozoic rift in south-central France 124
The Rhine Graben 127
Northern section of European Cenozoic rift 137
Summary aiid conclusions 139
Acknowledgments 141
References 142
Chapter 8. Deep crustal structure of the Rhine Graben from DEKORP–ECORS seismic reflection data: a summary 148
Introduction 148
Geological setting 149
Northern line 152
Southern line 153
Discussion: comparison between the northern and southern lines 154
Acknowledgments 155
References 155
Chapter 9. 3-D structure of the lithosphere beneath the southern Rhine Graben area 158
Introduction 158
3-D P-velocity model of the southern Rhine Graben area 159
Discussion of the inversion results 163
Acknowledgements 165
References 165
Chapter 10. Subsidence analysis and modelling of the Roer Valley Graben (SE Netherlands) 168
Introduction 168
Subsidence analysis 169
Discussion and conclusions 175
Acknowledgments 179
References 179
Chapter 11. Mafic alkaline magmatism associated with the European Cenozoic rift system 182
Introduction 182
Geochemical characteristics of the volcanic rocks 184
Discussion and summary 189
Acknowledgements 190
References 190
Chapter 12. The Valencia trough (western Mediterranean): an overview 192
Introduction 192
Megatectonic setting 194
Pre–late Oligocene basin evolution 196
Evolution of the Valencia trough 197
Magmatism 199
Structural configuration and stress regime 200
Paleomagnetic results 201
Crustal structure 202
Heat flow 203
Vertical movements 204
Discussion 206
Acknowledgements 207
References 207
Chapter 13. Styles of extension in the Pannonian Basin 212
Introduction 212
Reflection seismic sections and their interpretation 216
Sequence stratigraphy of the post-rift sedimentary succession 222
Discussion 223
Conclusions 225
Acknowledgements 226
References 226
Chapter 14. Tertiary evolution of the Intra-Carpathian area: a model 230
Basic features and problems of the Carpathian area 230
Timing of deformation, space problems, facies patterns and block rotation 232
Evolutionary model 239
Conclusions 247
Acknowledgements 248
References 248
Chapter 15. Review of Neogene and Quaternary volcanism of the Carpathian–Pannonian region 252
Introduction 252
Calc-alkaline volcanism 254
Alkaline volcanism 259
Conclusions 262
Acknowledgements 262
References 263
Chapter 16. Dnieper–Donets palaeorift 266
Introduction 266
Structural configuration and geological evolution 267
Geophysical data 271
Geodynamic considerations 274
Conclusions 280
References 280
Chapter 17. Baikal rift zone: structure and geodynamics 282
Introduction 282
Structural framework of basement and relation to rift pattern 283
Structure and evolution of rift basins 285
Rift dome: magnitude and timing of uplift 288
Crustal thickness 289
Lithospheric thickness 291
Geodynamic considerations 292
Conclusions 293
Acknowledgements 294
References 294
Chapter 18. Asthenospheric diapir beneath the Baikal rift: petrological constraints 296
Introduction 296
Thermal regime from petrological data 298
Discussion 300
Conclusions 302
Acknowledgments 302
References 302
Chapter 19. Faults and tectonic stresses of the Baikal Rift Zone 306
Introduction 306
Geological setting 308
Methods 308
Fault parameters and their relation 310
Tectonic stress field 312
Conclusions 314
Acknowledgments 316
References 316
Chapter 20. Heat flow variations in continental rifts 318
Introduction 318
Heat flow and thermal anomalies in Baikal rift zone 319
Heat flow and thermal anomalies in East African rift system 321
Heat flow and thermal anomalies of the Rhine–Lybian rift belt 325
Heat flow and thermal anomalies in Cordilleran rift system 328
Discussion and conclusions 330
Acknowledgements 330
References 330
Chapter 21. Geodynamics of the Shanxi Rift system, China 334
Introduction 334
Tectonic setting 334
Structural segmentation of the Shanxi Rift system 336
Cenozoic volcanism 340
Geophysics and lithosphere structure 341
Geodynamics of the Shanxi Rift system 346
Acknowledgments 348
References 348
Chapter 22.The Mesozoic-Cenozoic east China rift system 350
Introduction 350
Basement provinces and timing of rifting 350
Structural characteristics of rifted basins 353
Control of rifting on sedimentation, the example of the Bohai Bay basin 355
Magmatic activity 358
Crustal thickness and geothermal field 361
Geodynamic of the East China rift system 365
Acknowledgments 371
References 371
TECTONOPHYSICS—Volume 213—No. 1–2 374
Chapter 1. Tectonic setting of the Midcontinent Rift system 376
Background 376
Regional geology of the pre-rift basement 377
Midcontinent Rift system 381
Acknowledgements 387
References 387
Chapter 2. Geophysical investigations and crustal structure of the North American Midcontinent Rift system 392
Introduction 392
Geophysical investigations 394
Structure 397
Summary 404
Acknowledgements 404
References 404
Chapter 3. The igneous petrology and magmatic evolution of the Midcontinent rift system 408
Introduction 408
Magmatic evolution 411
Discussion 412
Acknowledgments 414
References 414
Chapter 4. The Midcontinent rift in the Lake Superior region with emphasis on its geodynamic evolution 416
Introduction 416
Regional geology 416
Subsidence history 421
Volume and eruption rate of volcanic rocks 421
Acknowledgements 422
References 422
Chapter 5. Speculations on the origin of the North American Midcontinent rift 424
Introduction 424
Plume derivation of some MCR basalts 425
Extension defined by dike swarms 426
Discussion 427
Summary 429
Acknowledgements 429
References 429
Chapter 6. Variations across and along a major continental rift: an interdisciplinary study of the Basin and Range Province, western USA 432
Introduction 433
Geologic overview 438
Igneous geochemistry 443
Geophysics 452
Conclusions 463
Acknowledgements 465
Appendix: Using crustal refraction profiles to estimate the buoyancy of the mantle lithosphere 465
References 466
Chapter 7. Tectonics and stratigraphy of the East Brazil Rift system: an overview 472
1. Introduction 472
2. Megatectonic setting 473
3. Stratigraphical development 476
4. Subsidence history 486
5. Structural styles 488
6. Magmatism 496
7. Coastal range uplift 499
8. Crustal framework 500
9. EBRIS geodynamic model 507
Acknowledgements 508
References 508
Chapter 8. The West and Central African rift systems: Foreword 514
References 515
Chapter 9. A plate tectonic setting for Mesozoic rifts of West and Central Africa 516
Introduction 516
Rift systems of West and Central Africa 519
Opening of the Atlantic Ocean 523
Plate tectonic interactions 523
Acknowledgements 524
References 524
Chapter 10. Early Cretaceous rifts of Western and Central Africa: an overview 528
Introduction 528
Basin structure and timing of subsidence 531
Basin genesis 537
Discussion and conclusions 539
Acknowledgments 540
References 541
Chapter 11. Regional framework, structural and petroleum aspects of rift basins in Niger, Chad and the Central African Republic (CAR.) 544
Introduction 544
Regional framework and tectonic evolution 545
Rift basin description and structure 552
Conclusions 558
Acknowledgements 558
References 559
Chapter 12. Tectonostratigraphic development of the Interior Sudan rifts, Central Africa 562
Introduction 562
Stratigraphic history of rifting 564
Structural and tectonic development 568
Magmatism 575
Regional tectonic synthesis 575
Conclusions 576
Acknowledgments 576
References 576
Chapter 13 Magmatism and rifting in Western and Central Africa, from Late Jurassic to Recent times 578
Introduction 578
Magmatic activity associated with intra-continental rifts 581
Mesozoic–Cenozoic rifting in West and Central Africa 582
Major tectonic events within the rift system 583
Mesozoic magmatism 584
Cenozoic magmatism 589
Summary 595
References 596
Chapter 14. Chronology and geodynamic setting of Cretaceous–Cenozoic rifting in West and Central Africa 602
Introduction 602
Permo-Triassic initial rifting episodes related to break up of Gondwana 602
Neocomian-early Aptian rifting episode 604
Aptian-Albian rifting episode 605
The Santonian (80–85 Ma) compressive event 605
Cenomanian–early Eocene sag phase of basin deepening 606
Intra-Eocene compressional event 606
Late Eocene–Oligocene rifting episode 606
Neogene magmatic activity 607
Role of subsidence /uplift during rifting 607
Conclusions 608
Acknowledgments 608
References 608
Chapter 15. Comparison of the Tanganyika, Malawi, Rukwa and Turkana Rift zones from analyses of seismic reflection data 610
Introduction 611
Background 611
Tanganyika and Malawi Rift Zones 619
Rukwa Rift Zone 621
Turkana Rift Zone 623
Discussion 627
Acknowlegments 629
References 630
Chapter 16. Some remarks on the structure and geodynamics of the Kenya Rift 632
1. Introduction 632
2. Crustal structure and kinematics 634
3. Lithospheric structure 636
4. Implications concerning the geodynamics of the Kenya Rift 641
Acknowledgements 642
References 642
Chapter 17. Nature of the crust beneath magmatically active continental rifts 644
Introduction 644
Flood basalt initiation of rift magmatism 645
Rise of the asthenosphere / lithosphere boundary 647
Asthenospheric melting and crustal accretion 648
Sources of mantle melts 648
The anatectic contribution to new igneous crust 649
Approach to a crustal model (Fig. 5) 653
Conclusions 655
Acknowledgments 656
References 656
TECTONOPHYSICS—Volume 215—No. 1–2 660
Chapter 1. The role of rifting in the evolution of the Earth's crust 662
Introduction 662
Aulacogens, peri-continental rifts and aulacogeosynclines 663
Break-up of Pangeas since Archean times 664
Mechanism of rifting 665
Conclusion 667
Acknowledgements 667
References 667
Chapter 2. Plate tectonics, plate moving mechanisms and rifting 670
Introduction 670
Palaeotectonic reconstructions 671
Main phases of plate boundary reorganization 671
Plate moving forces 681
Interaction of lithospheric plates 689
Conclusions 691
Acknowledgments 692
References 692
Chapter 3. Rifting of Africa and pattern of mantle convection beneath the African plate 696
Introduction 696
Pattern of tension axis orientations 697
Gravity anomalies and crustal thinning 699
Origin, growth and shape of the African plate 701
Geotectonic model 706
Deep structure, geophysical evidence 710
Unidirectional versus diverging mantle flow beneath active sea-floor spreading ridges 711
African lithospheric divergence, ALD, and global tectonics 712
Discussion 712
Acknowledgements 712
References 713
Chapter 4. Aulacogens and aulacogeosynclines: Regularities in setting and evolution 716
Introduction 716
Aulacogens 718
Aulacogeosyncunal zones 723
Metaplatforms 725
Conclusions 726
Acknowledgments 728
References 728
Chapter 5. From rifting to passive margin: the examples of the Red Sea, Central Atlantic and Alpine Tethys 730
Introduction 730
Red Sea and Gulf of Suez 731
Central Atlantic 734
Transform northwest African margin: example from the External Rif 743
Discussion 744
Conclusions 753
Acknowledgements 754
References 754
Chapter 6. Modelling the loading stresses associated with active continental rift systems 760
Introduction 760
Principles of modelling 761
Results of modelling 763
Discussion 773
Conclusions 774
Acknowledgements 775
References 776
Chapter 7. The mechanics of continental extension and sedimentary basin formation: A simple-shear/pure-shear flexural cantilever model 778
Introduction 778
A flexural cantilever model of continental extension and sedimentary basin formation 779
Interaction of multiple faults 786
Thermal subsidence 787
Erosion of footwall uplift and isostatic rebound 788
Discussion 788
Acknowledgements 791
References 791
Chapter 8. Modeling the tectonic development of the Tucano and Sergipe-Alagoas rift basins, Brazil 794
Introduction 795
Tectonic and geologic setting of the Tucano and Sergipe-Alagoas basins 795
Evidence for the involvement of intracrustal detachments in the formation of the Tucano and Sergipe-Alagoas basins 798
Kinematic development of the Tucano basin 800
The effect of flexural strength on the pattern of basin subsidence and gravity anomalies 804
Calculating the rheological strength of extended lithosphere 807
Implications of "instantaneous" lithospheric extension on rheological strength 810
Implications of finite rates of lithospheric extension on rheological strength 813
Implications of extension-induced magmatic underplating on rheological strength 815
Conclusions 817
Acknowledgements 819
Appendix 819
References 820
Chapter 9. Variation in extensional fault geometry related to heterogeneities within basement and sedimentary sequences 822
Introduction 822
Dominant low-angle heterogeneity sequence 822
Dominant high-angle heterogeneity sequence 824
Conclusions 825
Acknowledgements 826
References 826
Chapter 10. Intraplate stresses and dynamical aspects of rifted basins 828
Introduction 828
Tectonic stresses in the plates 830
Intraplate stresses and stratigraphy of rifted basins 831
Non-thermal contributions record to the subsidence 834
Implications 838
Conclusions 842
Acknowledgements 843
References 843
Chapter 11. Role of crustal stretching on subsidence of the continental crust 848
Introduction 848
Deep sedimentary basins within the continents 850
Intra-continental basins with thin crystalline crust: The case of the Black Sea 853
Continental rise of passive margins 857
Grabens with moderate extension 860
Intensely stretched regions 863
Reliability of determining the absence or presence of significant crustal stretching 864
Role of stretching in crustal subsidence on a global scale 865
Conclusions 866
Acknowledgements 866
References 867
Chapter 12. Development of asymmetric basins along continental transform faults 870
Introduction 870
Structural features unexplained by the pull-apart model 871
Discussion 876
Conclusions 879
Acknowledgements 880
References 880
Chapter 13. Geodynamics of rifting and implications for hydrocarbon habitat 882
Introduction 882
Geotectonic setting of rifts 883
Magmatism and rifting 885
Syn-rift subsidence 891
Structural style of rifts 893
Duration of rifting stage 896
Post-rift subsidence 897
Hydrocarbon habitat in rifted basins 900
Conclusions 903
Acknowledgments 905
References 905