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Proquest Dissertations Geologic history of the Cerberus Plains, Mars Item Type text; Dissertation-Reproduction (electronic) Authors Lanagan, Peter D. Publisher The University of Arizona. Rights Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author. Download date 01/10/2021 16:20:33 Link to Item http://hdl.handle.net/10150/290115 GEOLOGIC HISTORY OF THE CERBERUS PLAINS, MARS by Peter Denham Lanagan A Dissertation Submitted to the Faculty of tiie DEPARTMENT OF PLANETARY SCIENCES In Partial Fulfillment of the Requirements For the Degree of DOCTOR OF PHILOSOPHY In the Graduate College THE UNIVERSITY OF ARIZONA 2 0 0 4 UMI Number: 3145087 INFORMATION TO USERS The quality of this reproduction is dependent upon the quality of the copy submitted. Broken or indistinct print, colored or poor quality illustrations and photographs, print bleed-through, substandard margins, and improper alignment can adversely affect reproduction. In the unlikely event that the author did not send a complete manuscript and there are missing pages, these will be noted. Also, if unauthorized copyright material had to be removed, a note will indicate the deletion. UMI UMI Microform 3145087 Copyright 2004 by ProQuest Information and Learning Company. All rights reserved. This microform edition is protected against unauthorized copying under Title 17, United States Code. ProQuest Information and Learning Company 300 North Zeeb Road P.O. Box 1346 Ann Arbor, Ml 48106-1346 THE UNIVERSITY OF ARIZONA ® GRADUATE COLLEGE As members of the Final Examination Committee, we certify that we have read the dissertation prepared by Peter Denham Lanaqan entitled Geology of the Cerberus Plains, Mars and recommend that it be accepted as fulfilling the dissertation requirement for the Degree of Doctor of Philosophy A1 fre Date f Date Mffilpsh OJ'L^ Date V i ctoc- R. Date i.ffiatby D, Swi/idle cy^'f ZSX-/-- Date E1izabeth P. Turtle Final approval and acceptance of this dissertation is contingent upon the candidate * s submission of the final copy of the dissertation to the Graduate College. I hereby certify that I have read this dissertation prepared under my direction and recommend that it be accepted as fulfilling the dissertation requirement ^ jjjxBissertation Director Date A1 fred 5. McEwen 3 STATEMENT BY AUTHOR This dissertation has been submitted in partial fulfillment of requirements for an advanced degree at The University of Arizona and is deposited in the Uni­ versity Library to be made available to borrowers under rules of the library. Brief quotations from this dissertation are allowable without special per­ mission, provided that accurate acknowledgment of source is made. Requests for permission for extended quotation from or reproduction of this manuscript in whole or in part may be granted by the head of the major department or the Dean of the Graduate College when in his or her judgment the proposed use of the material is in the interests of scholarship. In all other instances, however, permission must be obtained from the author. SIGNED:/^ L, - 4 ACKNOWLEDGEMENTS Journeys are rarely completed without help from other people, and my passage though graduate school is no exception. I'd like to thank my dissertation advisor, Prof. Alfred McEwen, for advice, opportunities, access to useful tools, and patience. I'd also like to thank Prof. H. Jay Meiosh for listening to me at a critical point in my graduate career. I also wish to acknowledge PIRL-ites who have helped me over the years, especially Linda Hickcox for using her superadministrative powers for good rather than for evil and Joe Plassmann for fixing the things I break. Discussions with Devon Burr and Laszlo Keszthelyi were extremely fruitful and helped me look at scientific problems from different perspectives. I'd like to acknowledge many dear friends: Jason Barnes for yelling like a Deaniac, Ross Beyer for sharing the horror of seeing Viking scientists in tighty- whities, Jade Bond for creating trouble when trouble needed to be made, Fred Ciesla for inter-office rivalry, Barb Cohen for leaving little minefields of flowers, Gareth Collins for not calling me his mate, Ingrid Daubar for monkey shines, Josh Emery for commiseration, Ron Fevig for understanding what it means to be an n-th year, Jonathan Fortney for questionable webcam shows, Jen Crier and Andy Rivkin for showing how Swedes and Ferengi don't mix, Carl Hergenrother for silly asteroid stories, Terry Hurford for not taking my seat, Ralph Lorenz for contributing to entropy, Rachel Mastrapa for eloquently explaining why solar physics blew like a passing wind, Dave O'Brien for pushing Gallon-Beers, Matt Pasek for withstanding daily beatings, Jani Radebaugh for not suing me for harassment, Joe Spitale for not spiking my drink with sugar, Eric Wegryn for sharing knowledge of martian currency exchange rates, and Paul Withers for avoiding deportation to Guatemala. There are many more people I would acknowledge if I had the space. Rest assured, I know who you are (and I know where you live, too). At the risk of sounding serious, some individuals deserve special thanks. Josh Emery shared my office for many years and was always a willing confidant (much to the detriment of his own graduate studies). Joe Spitale, Jani Radebaugh, and Ron Fevig went above and beyond the call of friendship during my hospital­ ization by keeping me company even though I spent most of that time complaining about bodily malfunctions. Jade Bond has been a tremendous help in keeping me sane these last few months, partly through her assistance in practical matters but mostly just by being around. Although others have been helpful to me. Jade is the only person hsted on this page who gets a big kiss from me. 5 DEDICATION To my parents, for reasons which extend beyond their mixing strands of DNA. 6 TABLE OF CONTENTS LIST OF FIGURES 9 LIST OF TABLES 11 ABSTRACT 12 CHAPTER 1 Introduction 14 1.1 Background 14 1.2 Summary of Work 17 CHAPTER 2 Rootless Cones on Mars Indicating the Presence of Shallow Equatorial Ground-ice in Recent Times 20 2.1 Introduction 20 2.2 Observations of Rootless Cones on Mars and Earth 22 2.3 Implications for Recent Equatorial Ground-ice 25 CHAPTER 3 Geomorphic Analysis of the Cerberus Plains: Con­ straints on the Emplacement of the Youngest Lava Flows on Mars 28 3.1 Introduction 28 3.2 Background 30 3.3 Datasets and Mapping Methods 33 3.3.1 Topography 33 3.3.2 Imaging 35 3.3.3 Radar 35 3.4 Observations 36 3.4.1 Topography 36 3.4.2 Imaging . 39 3.4.2.1 Platy-Ridged Surfaces 43 3.4.2.2 Pitted Plateaus 43 3.4.2.3 Patterned Surfaces 46 3.4.2.4 Overlapping Subparallel Ridges 46 3.4.2.5 Mantled Surfaces 49 3.4.3 Radar 49 3.5 Interpretations 52 3.5.1 Flood Lavas 52 3.5.2 Possible Pyroclastic Deposits 60 3.6 Stratigraphic Relationships of Cerberus Plains Lavas with Surround­ ing Terrains 62 7 TABLE OF CONTENTS — Continued 3.6.1 Medusae Fossae Formation 63 3.6.2 Channels and Valles 63 3.6.2.1 Athabasca Valles . 65 3.6.2.2 Eastern Cerberus Plains/Western Cerberus Plains Breach 68 3.6.2.3 Railway Valles 68 3.6.2.4 Marte Valles 73 3.7 Crater Densities of Large Lava Flows 73 3.7.1 Statistics of Small Craters 76 3.7.2 Statistics of Large Craters 86 3.8 Discussion . 89 3.8.1 Geologic History of the Cerberus Plains 89 3.8.2 Volume Estimates for Volcanics 91 3.8.3 Time to Emplace Volcanic Fields 94 3.8.4 Hydrologic Effects 95 3.8.5 Climatic Effects 96 3.9 Summary 97 CHAPTER 4 Lake Athabasca, Mars; Evidence for a Late- Amazonian Paleolake 99 4.1 Introduction 99 4.2 Background 99 4.3 Observations 100 4.3.1 Topography 100 4.3.2 Imaging 101 4.3.2.1 Scarps and Benches . 101 4.3.2.2 Cratered cones 103 4.4 Interpretations 107 4.4.0.3 Shorelines 107 4.4.0.4 Rootless Cones 108 4.4.0.5 Spillways 109 4.4.0.6 Closed Basin . 110 4.5 Discussion Ill 4.5.1 Physiography Ill 4.5.2 Sinks of Athabasca Floodwaters 112 4.5.2.1 Overland Flow 112 4.5.2.2 Freezing and Sublimation 113 4.5.2.3 Infiltration 114 8 TABLE OF CONTENTS — Continued 4.5.3 Timing of Floods 116 4.6 Conclusions 118 CHAPTER, 5 Summary and Conclusions 120 APPENDIX A Images of Cerberus Plains Rootless Cones 122 APPENDIX B Images of Lake Athabasca Shorelines 126 REFERENCES 132 9 LIST OF FIGURES 1.1 Maps of Mars 16 2.1 Locations of cone groups in the Cerberus Plains 21 2.2 Martian and Icelandic cone comparison 23 3.1 Cerberus Plains location map 29 3.2 Cerberus Plains topography 34 3.3 Cerberus Plains radar backscatter map 37 3.4 Cerberus Plains geomorphology 38 3.5 Eastern Cerberus Plains map 40 3.6 Western Cerberus Plains map 41 3.7 Regions of MOC images examined of the Cerberus Plains 42 3.8 MOC image of platy-ridged lavas 44 3.9 MOC image of pitted plateaus 45 3.10 THEMIS image of platy-ridged lavas 47 3.11 Medusae Fossae Formation superposition 48 3.12 MOC image of Cerberus Fossae 50 3.13 Air photo of the Burfell lava flow 54 3.14 THEMIS mosaic of Athabasca Valles 57 3.15 Eastern Cerberus Plains pit crater 58 3.16 Filled portion of Cerberus Fossae 59 3.17 Lavas superimposed over Medusae Fossae Formation 64 3.18 Athabasca Valles 66 3.19 MOC images of Athabasca Valles .
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