Koeberl / Henkel Impact Tectonics

2005
ISBN: 978-3-540-27548-0
Verlag: Springer Berlin Heidelberg
Format: PDF
Kopierschutz: 1 - PDF Watermark

E-Book, Englisch, 552 Seiten

Reihe: Impact Studies

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.

Autoren/Hrsg.

Koeberl, Christian

Henkel, Herbert

Inhaltsverzeichnis

1;Preface;5
2;Acknowledgements;8
3;Contents;9
4;List of contributors;11
5;"Pseudotachylites" in Large Impact Structures;20
5.1;1 Introduction;21
5.2;2 Historical Overview;23
5.3;3 What Should Be Called “Pseudotachylite?”;30
5.4;4 The Early (1970s-end 1980s) Controversy;36
5.5;5T The Mid-1990s “Problematics” - A, B, S, E types, Tagamite and Shock Veins;36
5.6;6 The Setting of Pseudotachylitic Breccia in Impact Craters;44
5.7;7 “ Pseudotachylite” or “Pseudotachylitic Breccia”, Compari-son of Vredefort- Witwatersrand Breccias and Tectonic Friction Melt Rock;52
5.8;8 Problematics;57
5.9;9 Conclusions;63
5.10;Acknowledgements;64
5.11;References;65
6;The Mechanics of Pseudotachylite Formation in Impact Events;73
6.1;1 Introduction;74
6.2;2 Frictional Heating of Rocks Rocks;77
6.3;3 Brittle Deformation of a Large Rock Mass;80
6.4;4 Stresses and Strains in an Impact Event;83
6.5;5 Fault Slip in a Deforming Rock Mass;87
6.6;6 Friction Melting in Shear Zones;89
6.7;7 The Pseudotachylite Conundrum Conundrum;91
6.8;8 Conclusions;94
6.9;Acknowledgement;96
6.10;References;96
7;Silicified Cone-in-Cone Structures from Erfoud ( Morocco): A Comparison with Impact- Generated Shatter Cones;99
7.1;1 Introduction;100
7.2;2 Cone-in-Cone Structures;100
7.3;3 Silicified Cone-in-Cone Structures from Erfoud, Morocco;109
7.4;4 Shatter Cones;114
7.5;5 Comparing Cone-in-Cone and Shatter Cone Structures;124
7.6;Acknowledgments;125
7.7;References;125
8;Redistribution of Lithologies in Impact-induced Dikes of Impact Structures;129
8.1;1 Introduction;129
8.2;2 Clast-bearing Dikes Formed by Injection;131
8.3;3 Clast-bearing Dikes Formed by Squeezing;138
8.4;4 Clast-bearing Dikes Formed by Infilling;139
8.5;5 Displaced Lithologies in Injected Dikes;142
8.6;6 Conclusion;143
8.7;Acknowledgements;144
8.8;References;144
9;The Preliminary Analysis of Polygonal Impact Craters within Greater Hellas Region, Mars;148
9.1;1 Purpose of This Study;149
9.2;2 Earlier Studies and the Formation of Polygonal Craters;149
9.3;3 Impact Structures and Fracturing;154
9.4;4 The Schematic Geology of the Greater Hellas Region;155
9.5;5 Methods;160
9.6;6 Results;162
9.7;7 Discussion and Conclusions;169
9.8;8 Summary and Outlines for Future Studies;173
9.9;Acknowledgements;175
9.10;References;175
10;BP and Oasis Impact Structures, Libya: Remote Sensing and Field Studies;178
10.1;1 Introduction;179
10.2;2 General Geology of BP and Oasis Impact Structures;183
10.3;3 Remote Sensing Studies;185
10.4;4 BP Impact Structure;186
10.5;5 Oasis Impact Structure;194
10.6;6 Field Work at BP and Oasis – First Observations;201
10.7;7 Summary and Conclusions;203
10.8;Acknowledgments;204
10.9;References;205
11;Late Modification-Stage Tectonic Deformation of the Popigai Impact Structure, Russia;208
11.1;1 Introduction;210
11.2;2 General Geology of the Popigai Crater;211
11.3;3 Post-Impact Tectonic Structure of the Popigai Crater;214
11.4;4 Fracture Deformations of Impact Rock Bodies;217
11.5;5 Summary and Concluding Remarks;223
11.6;Acknowledgements;226
11.7;References;226
12;Settings of Meteorite Impact Structures in the Svecofennian Crustal Domain;228
12.1;1 Introduction;229
12.2;2 Svecofennian Crustal Domain as a Target: Crystalline Basement and Sedimentary Cover;235
12.3;3 Paleogeological and Present-Day Settings of Impact Structures;240
12.4;4 Post-impact Alteration of Impact Structures;248
12.5;5 Apparent Cratering Rates;253
12.6;6 Conclusions;255
12.7;Acknowledgements;256
12.8;References;257
13;Geophysical Investigations of the Siljan Impact Structure – A Short Review;263
13.1;1 Background;264
13.2;2 Morphology and Crater Diameter;269
13.3;3 Geophysical Data;273
13.4;4 Interpretations Based on Geophysical Data;281
13.5;5 Petrological and Geochemical Features;284
13.6;6 Shallow and Deep Drillings;286
13.7;7 Discussion;288
13.8;8 Conclusions and Suggestions;292
13.9;Acknowledgements;297
13.10;References;297
14;Mjølnir Crater as a Result of Oblique Impact: Asymmetry Evidence Constrains Impact Direction and Angle;300
14.1;1 Introduction;302
14.2;2 Mjølnir as an Oblique Impact Event;304
14.3;3 Impact Direction and Angle;311
14.4;4 Mjølnir Impact Obliquity Constrains Models for Near-Field Perturbations;313
14.5;5 Conclusions;318
14.6;Acknowledgments;318
14.7;References;319
15;The Duobblon Structure - A Small Segment of a Large Precambrian Impact Structure?;322
15.1;1 Introduction;322
15.2;2 Previous Geological Interpretation;323
15.3;3 The Impact Concept;325
15.4;4 Tectonic Structures;331
15.5;5 Mineralizations;332
15.6;6 Discussion: Reinterpretation of the Duobblon Stratigra-phy as a Sequence of Impactites;332
15.7;7 Conclusions;335
15.8;Acknowledgements;335
15.9;References;336
16;Åvike Bay – a 10 km Diameter Possible Impact Structure at the Bothnian Sea Coast of Central Sweden.;338
16.1;1 Introduction;339
16.2;2 Background;340
16.3;3 Topography and Fracture Pattern;342
16.4;4 Geology;342
16.5;5 Occurrence of Microdeformation Features in Quartz;347
16.6;6 Rock Physical Properties;348
16.7;7 Magnetic Anomaly;350
16.8;8 Age of the Åvike Bay Structure;352
16.9;9 Discussion and Conclusions;352
16.10;Acknowledgements;355
16.11;References;355
17;The Structure and Age of the Kaali Main Crater, Island of Saaremaa, Estonia;356
17.1;1 Introduction;357
17.2;2 Early Descriptions of the Main Crater Morphology;357
17.3;3 Formation of the Crater;361
17.4;4 Recent Data on the Crater Structure;364
17.5;5 On the Age of the Impact;364
17.6;6 Conclusions;367
17.7;Acknowledgements;368
17.8;References cited;368
18;The Lockne Crater: Revision and Reassessment of Structure and Impact Stratigraphy;371
18.1;1 Introduction;374
18.2;2 Terminology;374
18.3;3 Research History;376
18.4;4 Stratigraphy;377
18.5;5 The Inner Crater;378
18.6;6 The Brim;379
18.7;7 Resurge Gullies;385
18.8;8 Ynntjärnen Breccia;388
18.9;9 Large Masses of Crystalline Ejecta;391
18.10;10 The Lockne Breccia and Loftarstone;393
18.11;11 The Sub-Cambrian Peneplain and the Crater Rim;394
18.12;12 Younger Tectonic Structures;395
18.13;13 Conclusions;398
18.14;Acknowledgements;400
18.15;References;400
19;A Study of Impact Fracturing and Electric Resistivity Related to the Lockne Impact Structure, Sweden;403
19.1;1 Background;403
19.2;2 Methods;409
19.3;3 Results;413
19.4;4 Discussion;414
19.5;5 Conclusions;416
19.6;Acknowledgements;417
19.7;References;417
20;Hydrocode Simulation of the Lockne Marine Target Impact Event;419
20.1;1 Introduction;419
20.2;2 Numerical Model;422
20.3;3 Shallow Excavation;423
20.4;4 Ejecta Distribution;426
20.5;5 Oblique Impact;431
20.6;6 Conclusions;434
20.7;Acknowledgements;435
20.8;References;435
21;Numerical Simulation of Shock Propagation in Heterogeneous Solids;437
21.1;1 Introduction;438
21.2;2 Experimental Shock Compression of Rocks;439
21.3;3 Numerical Modelling;442
21.4;4 Simulations in Lagrangian Mode;445
21.5;5 Simulations in Eulerian Mode;451
21.6;6 Implications, Outlook, and Some Precautionary Notes;455
21.7;Acknowledgements;457
21.8;References;457
22;The Kentland Impact Crater, Indiana (USA): An Apatite Fission- Track Age Determination Attempt;460
22.1;1 Introduction;461
22.2;2 Newton County Stone Quarry (Kentland) Geology;465
22.3;3 Working Hypothesis;466
22.4;4 Samples and Fission-Track Methods;467
22.5;5 Fission-Track Results;471
22.6;6 Discussion;475
22.7;Acknowledgements;476
22.8;References;477
23;The Combined Petrographic and Chemical Analysis of end- Permian Kerogens;480
23.1;1 Introduction;481
23.2;2 Experimental;483
23.3;3 Results and Discussion;484
23.4;4 Conclusions;489
23.5;Acknowledgements;490
23.6;References;490
24;Economic Mineral Deposits in Impact Structures: A Review;492
24.1;1 Introduction;493
24.2;2 Pre-Impact (Progenetic) Deposits in Large Impact Structures;498
24.3;3 Syngenetic, Directly Impact-related Deposits;515
24.4;4 Hydrothermal Processes in Impact Structures;528
24.5;5 Other Deposits in, and Benefits from, Impact Structures;544
24.6;6 Final Remarks;547
24.7;Acknowledgements;548
24.8;References;548