Impact Cratering

Dr Gordon "Oz" Osinski is the NSERC/MDA/CSA Industrial Research Chair in Planetary Geology in the Departments of Earth Sciences and Physics and Astronomy at Western University, Canada. He holds a B.Sc. (Hons) First Class in Geology from the University of St. Andrews, Scotland (1999) and a Ph.D., also in Geology (2004), from the University of New Brunswick, Canada. His research covers the tectonics of impact crater formation, the generation of impact melts, emplacement of ejecta, and post-impact processes such as impact-associated hydrothermal activity. He has published more than 70 papers in peer-reviewed journals and special papers and has given over 60 conference presentations since 2001. Dr Elisabetta Pierazzo, who tragically died during the preparation of this book, was a Research Scientist at the Planetary Science Institute and an Adjunct Assistant Research Scientist at the Lunar & Planetary Laboratory, University of Arizona, both located in Tucson, Arizona. She held a Laurea in Physics from the University of Padua, Italy (1988) and a Ph.D. in Planetary Sciences from University of Arizona (1997). She was a world renowned expert on the numerical modelling of impact events, focusing on the environmental effects of impact events, oblique impacts, and impact melt production.

• Preface xiList of contributors xii1 Impact cratering: processes and products 1Gordon R. Osinski and Elisabetta Pierazzo1.1 Introduction 11.2 Formation of hypervelocity impact craters 31.3 Morphology and morphometry of impact craters 81.4 Impactites 121.5 Recognition of impact craters 141.6 Destructive effects of impact events 151.7 Benefi cial effects of impact events 151.8 When a crater does not exist: other evidence for impact events 161.9 Concluding remarks 16References 172 Population of impactors and the impact cratering rate in the inner Solar System 21Patrick Michel and Alessandro Morbidelli2.1 Introduction 212.2 Population of impactors in the inner Solar System 222.3 Impact frequency of NEOs with the Earth 242.4 Comparison with the impact record on terrestrial planets 252.5 Variability of the impact frequency during the last 3 Ga 262.6 The early cratering history of the Solar System 272.7 Conclusions 28References 293 The contact and compression stage of impact cratering 32H. Jay Melosh3.1 Introduction 323.2 Maximum pressures during contact and compression 353.3 Jetting during contact and compression 373.4 The isobaric core 383.5 Oblique impact 393.6 The end of contact and compression 40References 424 Excavation and impact ejecta emplacement 43Gordon R. Osinski, Richard A. F. Grieve and Livio L. Tornabene4.1 Introduction 434.2 Excavation 434.3 Impact plume 464.4 Generation of continuous ejecta blankets 474.5 Rayed craters 514.6 Generation of multiple ejecta layers 524.7 Distal impact ejecta 564.8 Depth of excavation 57References 575 The modification stage of crater formation 60Thomas Kenkmann, Gareth S. Collins and Kai Wünnemann5.1 Introduction 605.2 Morphology and morphometry of simple and complex impact craters 625.3 Kinematics of crater collapse 645.4 Subsurface structure of complex impact craters 665.5 Mechanics of cavity collapse: what makes the target so weak? 695.6 Effects of oblique impact incidences on cavity collapse 715.7 Effects of rheologically complex targets on cavity modifi cation 71References 736 Impact-induced hydrothermal activity 76Kalle Kirsimäe and Gordon R. Osinski6.1 Introduction 766.2 Formation and development of the post-impact thermal field 766.3 Composition and evolution of the hydrothermal fluids and mineralization 796.4 Implications for extraterrestrial impacts and microbial life 85References 877 Impactites: their characteristics and spatial distribution 90Richard A. F. Grieve and Ann M. Therriault7.1 Introduction 907.2 Autochthonous impactites 907.3 Parautochthonous impactites 917.4 Allochthonous impactites 927.5 Concluding remarks 101References 1028 Shock metamorphism 106Ludovic Ferrière and Gordon R. Osinski8.1 Introduction 1068.2 Shock metamorphic features 1088.3 Post-shock thermal features 1198.4 Concluding remarks 120References 1219 Impact melting 125Gordon R. Osinski, Richard A. F. Grieve, Cassandra Marion and Anna Chanou9.1 Introduction 1259.2 Why impact melting occurs 1259.3 Terrestrial impact melt products 1269.4 Planetary impact melt products 1399.5 Impactor contamination 1419.6 Concluding remarks 142References 14210 Environmental effects of impact events 146Elisabetta Pierazzo and H. Jay Melosh10.1 Introduction 14610.2 The impact hazard 14610.3 The impact cratering process 14710.4 Shock wave effects 14810.5 Ejecta launch 15010.6 Long-term atmospheric perturbation 15110.7 The response of the Earth system to large impacts 15210.8 Environmental impact effects favourable for life 15310.9 Concluding remarks 153References 15411 The geomicrobiology of impact structures 157Charles S. Cockell, Gordon R. Osinski and Mary A. Voytek11.1 Introduction 15711.2 Physical changes 15811.3 Chemical changes 16511.4 Impact events and weathering 16611.5 Impoverishment or enrichment? 17111.6 Astrobiological implications 17211.7 Concluding remarks 172References 17212 Economic deposits at terrestrial impact structures 177Richard A. F. Grieve12.1 Introduction 17712.2 Progenetic deposits 17712.3 Syngenetic deposits 18212.4 Epigenetic deposits 18612.5 Hydrocarbon accumulations 18612.6 Concluding remarks 189References 19013 Remote sensing of impact craters 194Shawn P. Wright, Livio L. Tornabene and Michael S. Ramsey13.1 Introduction 19413.2 Background 19413.3 Photogeology 19613.4 Morphometry, altimetry, topography 19613.5 Composition derived from remote sensing 19613.6 Physical properties derived from remote sensing 20113.7 General spectral enhancement and mapping techniques 20213.8 Case studies 20313.9 Concluding remarks 207References 20714 Geophysical studies of impact craters 211Joanna Morgan and Mario Rebolledo-Vieyra14.1 Introduction 21114.2 Geophysical signature of terrestrial impacts 21114.3 The resolution of geophysical data 21514.4 Modelling geophysical data 21614.5 Case studies 217References 22015 Projectile identification in terrestrial impact structures and ejecta material 223Steven Goderis, François Paquay and Philippe Claeys15.1 Introduction 22315.2 Current situation: projectile identification at impact craters and ejecta layers 22315.3 Methodology 22615.4 Review of identified projectiles 23415.5 Concluding remarks 235References 23516 The geochronology of impact craters 240Simon P. Kelley and Sarah C. Sherlock16.1 Introduction 24016.2 Techniques used for dating terrestrial impact craters 24116.3 Impact craters at the K–Pg boundary 24616.4 Geochronology of impacts, flood basalts and mass extinctions 24716.5 Using geochronology to identify clusters of impacts in the geological record 24816.6 Concluding remarks 250References 25117 Numerical modelling of impact processes 254Gareth S. Collins, Kai Wünnemann, Natalia Artemieva and Elisabetta Pierazzo17.1 Introduction 25417.2 Fundamentals of impact models 25617.3 Material models 26217.4 Validation, verifi cation and benchmarking 26717.5 Concluding remarks 267References 26818 Comparison of simple impact craters: a case study of Meteor and Lonar Craters 271Horton E. Newsom, Shawn P. Wright, Saumitra Misra and Justin J. Hagerty18.1 Introduction 27118.2 Meteor Crater, Arizona 27118.3 Lonar Crater 27418.4 Comparisons and planetary implications 28318.5 Summary and concluding remarks 285Acknowledgements 285References 28619 Comparison of mid-size terrestrial complex impact structures: a case study 290Gordon R. Osinski and Richard A. F. Grieve19.1 Introduction 29019.2 Overview of craters 29019.3 Comparisons and implications 30119.4 Comparisons with lunar and Martian impact craters 30219.5 Concluding remarks 303References 30320 Processes and products of impact cratering: glossary and definitions 306Gordon R. Osinski20.1 Introduction 30620.2 General definitions 30620.3 Morphometric definitions and equations 30720.4 Impactites 308References 308Index 310

"I fully recommend this book to anyone interested in impacts and their geological influence.  Impact Cratering is first class, fascinating reading to the expert, I am sure, as well as the novice (like your reviewer), and destined to be the standard reference for years to come."  (Geological Journal, 4 April 2014)“This book is now the single best starting point for anyone interested in almost any aspect of impact cratering.  Summing Up: Highly recommended.  Upper-division undergraduates and  above.”  (Choice, 1 November 2013)