Impact Tectonics (eBook)

Christian Koeberl, Herbert Henkel (Herausgeber)

eBook Download: PDF

2005 | 2005
XIX, 552 Seiten
Springer Berlin (Verlag)
978-3-540-27548-0 (ISBN)

Infos

A collection of international contributions presenting current knowledge of impact tectonics, geological and geophysical investigations of terrestrial impact structures, and suggested new impact structures, resulting from the IMPACT program.

Inhalt

Preface 5
Acknowledgements 8
Contents 9
List of contributors 11
"Pseudotachylites" in Large Impact Structures 20
1 Introduction 21
2 Historical Overview 23
3 What Should Be Called “Pseudotachylite?” 30
4 The Early (1970s-end 1980s) Controversy 36
5T The Mid-1990s “Problematics” - A, B, S, E types, Tagamite and Shock Veins 36
6 The Setting of Pseudotachylitic Breccia in Impact Craters 44
7 “ Pseudotachylite” or “Pseudotachylitic Breccia”, Compari-son of Vredefort- Witwatersrand Breccias and Tectonic Friction Melt Rock 52
8 Problematics 57
9 Conclusions 63
Acknowledgements 64
References 65
The Mechanics of Pseudotachylite Formation in Impact Events 73
1 Introduction 74
2 Frictional Heating of Rocks Rocks 77
3 Brittle Deformation of a Large Rock Mass 80
4 Stresses and Strains in an Impact Event 83
5 Fault Slip in a Deforming Rock Mass 87
6 Friction Melting in Shear Zones 89
7 The Pseudotachylite Conundrum Conundrum 91
8 Conclusions 94
Acknowledgement 96
References 96
Silicified Cone-in-Cone Structures from Erfoud ( Morocco): A Comparison with Impact- Generated Shatter Cones 99
1 Introduction 100
2 Cone-in-Cone Structures 100
3 Silicified Cone-in-Cone Structures from Erfoud, Morocco 109
4 Shatter Cones 114
5 Comparing Cone-in-Cone and Shatter Cone Structures 124
Acknowledgments 125
References 125
Redistribution of Lithologies in Impact-induced Dikes of Impact Structures 129
1 Introduction 129
2 Clast-bearing Dikes Formed by Injection 131
3 Clast-bearing Dikes Formed by Squeezing 138
4 Clast-bearing Dikes Formed by Infilling 139
5 Displaced Lithologies in Injected Dikes 142
6 Conclusion 143
Acknowledgements 144
References 144
The Preliminary Analysis of Polygonal Impact Craters within Greater Hellas Region, Mars 148
1 Purpose of This Study 149
2 Earlier Studies and the Formation of Polygonal Craters 149
3 Impact Structures and Fracturing 154
4 The Schematic Geology of the Greater Hellas Region 155
5 Methods 160
6 Results 162
7 Discussion and Conclusions 169
8 Summary and Outlines for Future Studies 173
Acknowledgements 175
References 175
BP and Oasis Impact Structures, Libya: Remote Sensing and Field Studies 178
1 Introduction 179
2 General Geology of BP and Oasis Impact Structures 183
3 Remote Sensing Studies 185
4 BP Impact Structure 186
5 Oasis Impact Structure 194
6 Field Work at BP and Oasis – First Observations 201
7 Summary and Conclusions 203
Acknowledgments 204
References 205
Late Modification-Stage Tectonic Deformation of the Popigai Impact Structure, Russia 208
1 Introduction 210
2 General Geology of the Popigai Crater 211
3 Post-Impact Tectonic Structure of the Popigai Crater 214
4 Fracture Deformations of Impact Rock Bodies 217
5 Summary and Concluding Remarks 223
Acknowledgements 226
References 226
Settings of Meteorite Impact Structures in the Svecofennian Crustal Domain 228
1 Introduction 229
2 Svecofennian Crustal Domain as a Target: Crystalline Basement and Sedimentary Cover 235
3 Paleogeological and Present-Day Settings of Impact Structures 240
4 Post-impact Alteration of Impact Structures 248
5 Apparent Cratering Rates 253
6 Conclusions 255
Acknowledgements 256
References 257
Geophysical Investigations of the Siljan Impact Structure – A Short Review 263
1 Background 264
2 Morphology and Crater Diameter 269
3 Geophysical Data 273
4 Interpretations Based on Geophysical Data 281
5 Petrological and Geochemical Features 284
6 Shallow and Deep Drillings 286
7 Discussion 288
8 Conclusions and Suggestions 292
Acknowledgements 297
References 297
Mjølnir Crater as a Result of Oblique Impact: Asymmetry Evidence Constrains Impact Direction and Angle 300
1 Introduction 302
2 Mjølnir as an Oblique Impact Event 304
3 Impact Direction and Angle 311
4 Mjølnir Impact Obliquity Constrains Models for Near-Field Perturbations 313
5 Conclusions 318
Acknowledgments 318
References 319
The Duobblon Structure - A Small Segment of a Large Precambrian Impact Structure? 322
1 Introduction 322
2 Previous Geological Interpretation 323
3 The Impact Concept 325
4 Tectonic Structures 331
5 Mineralizations 332
6 Discussion: Reinterpretation of the Duobblon Stratigra-phy as a Sequence of Impactites 332
7 Conclusions 335
Acknowledgements 335
References 336
Åvike Bay – a 10 km Diameter Possible Impact Structure at the Bothnian Sea Coast of Central Sweden. 338
1 Introduction 339
2 Background 340
3 Topography and Fracture Pattern 342
4 Geology 342
5 Occurrence of Microdeformation Features in Quartz 347
6 Rock Physical Properties 348
7 Magnetic Anomaly 350
8 Age of the Åvike Bay Structure 352
9 Discussion and Conclusions 352
Acknowledgements 355
References 355
The Structure and Age of the Kaali Main Crater, Island of Saaremaa, Estonia 356
1 Introduction 357
2 Early Descriptions of the Main Crater Morphology 357
3 Formation of the Crater 361
4 Recent Data on the Crater Structure 364
5 On the Age of the Impact 364
6 Conclusions 367
Acknowledgements 368
References cited 368
The Lockne Crater: Revision and Reassessment of Structure and Impact Stratigraphy 371
1 Introduction 374
2 Terminology 374
3 Research History 376
4 Stratigraphy 377
5 The Inner Crater 378
6 The Brim 379
7 Resurge Gullies 385
8 Ynntjärnen Breccia 388
9 Large Masses of Crystalline Ejecta 391
10 The Lockne Breccia and Loftarstone 393
11 The Sub-Cambrian Peneplain and the Crater Rim 394
12 Younger Tectonic Structures 395
13 Conclusions 398
Acknowledgements 400
References 400
A Study of Impact Fracturing and Electric Resistivity Related to the Lockne Impact Structure, Sweden 403
1 Background 403
2 Methods 409
3 Results 413
4 Discussion 414
5 Conclusions 416
Acknowledgements 417
References 417
Hydrocode Simulation of the Lockne Marine Target Impact Event 419
1 Introduction 419
2 Numerical Model 422
3 Shallow Excavation 423
4 Ejecta Distribution 426
5 Oblique Impact 431
6 Conclusions 434
Acknowledgements 435
References 435
Numerical Simulation of Shock Propagation in Heterogeneous Solids 437
1 Introduction 438
2 Experimental Shock Compression of Rocks 439
3 Numerical Modelling 442
4 Simulations in Lagrangian Mode 445
5 Simulations in Eulerian Mode 451
6 Implications, Outlook, and Some Precautionary Notes 455
Acknowledgements 457
References 457
The Kentland Impact Crater, Indiana (USA): An Apatite Fission- Track Age Determination Attempt 460
1 Introduction 461
2 Newton County Stone Quarry (Kentland) Geology 465
3 Working Hypothesis 466
4 Samples and Fission-Track Methods 467
5 Fission-Track Results 471
6 Discussion 475
Acknowledgements 476
References 477
The Combined Petrographic and Chemical Analysis of end- Permian Kerogens 480
1 Introduction 481
2 Experimental 483
3 Results and Discussion 484
4 Conclusions 489
Acknowledgements 490
References 490
Economic Mineral Deposits in Impact Structures: A Review 492
1 Introduction 493
2 Pre-Impact (Progenetic) Deposits in Large Impact Structures 498
3 Syngenetic, Directly Impact-related Deposits 515
4 Hydrothermal Processes in Impact Structures 528
5 Other Deposits in, and Benefits from, Impact Structures 544
6 Final Remarks 547
Acknowledgements 548
References 548

Produkt-Details

• Erscheint lt. Verlag: 17.12.2005
• Reihe/Serie: Impact Studies
• Reihe/Serie: Impact Studies
• Zusatzinfo: XIX, 552 p.
• Verlagsort: Berlin
• Sprache: englisch
• Themenwelt: Naturwissenschaften ► Geowissenschaften ► Geologie
• Themenwelt: Naturwissenschaften ► Physik / Astronomie
• Themenwelt: Technik
• Schlagworte: Deformation • dike • Economic Ecology • Fracture Patterns • Impact Mechanisms • Pseudotachylite Formation • Structural Geology • Tectonics
• ISBN-10: 3-540-27548-7 / 3540275487
• ISBN-13: 978-3-540-27548-0 / 9783540275480