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The Periglacial Landscape of Utopia Planitia; Geologic Evidence for Recent Climate Change on Mars

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The Periglacial Landscape of Utopia Planitia; Geologic Evidence for Recent Climate Change on Mars Western University Scholarship@Western Electronic Thesis and Dissertation Repository 1-23-2013 12:00 AM The Periglacial Landscape Of Utopia Planitia; Geologic Evidence For Recent Climate Change On Mars. Mary C. Kerrigan The University of Western Ontario Supervisor Dr. Marco Van De Wiel The University of Western Ontario Joint Supervisor Dr. Gordon R Osinski The University of Western Ontario Graduate Program in Geography A thesis submitted in partial fulfillment of the equirr ements for the degree in Master of Science © Mary C. Kerrigan 2013 Follow this and additional works at: https://ir.lib.uwo.ca/etd Part of the Climate Commons, Geology Commons, Geomorphology Commons, and the Physical and Environmental Geography Commons Recommended Citation Kerrigan, Mary C., "The Periglacial Landscape Of Utopia Planitia; Geologic Evidence For Recent Climate Change On Mars." (2013). Electronic Thesis and Dissertation Repository. 1101. https://ir.lib.uwo.ca/etd/1101 This Dissertation/Thesis is brought to you for free and open access by Scholarship@Western. It has been accepted for inclusion in Electronic Thesis and Dissertation Repository by an authorized administrator of Scholarship@Western. For more information, please contact [email protected]. THE PERIGLACIAL LANDSCAPE OF UTOPIA PLANITIA; GEOLOGIC EVIDENCE FOR RECENT CLIMATE CHANGE ON MARS by Mary C. Kerrigan Graduate Program in Geography A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science The School of Graduate and Postdoctoral Studies The University of Western Ontario London, Ontario, Canada © Mary C. Kerrigan 2013 ii THE UNIVERSITY OF WESTERN ONTARIO School of Graduate and Postdoctoral Studies CERTIFICATE OF EXAMINATION Joint Supervisor Examiners ______________________________ Dr. Marco Van de Wiel ______________________________ Dr. Katrina Moser Joint Supervisor ______________________________ Dr. Phil Stooke ______________________________ Dr. Gordon R. Osinski ______________________________ Dr. Stephen Hicock The thesis by Mary Christine Kerrigan entitled: The Periglacial Landscape of Utopia Planitia; Geologic Evidence for Recent Climate Change on Mars is accepted in partial fulfillment of the requirements for the degree of Master of Science __________________________ ______________________________ Date Dr. Jeff Hopkins Chair of the Thesis Examination Board iii Abstract The northern plains of Utopia Planitia, Mars, hosts an abundance of potential periglacial landforms including scalloped depressions, gullies, and polygon networks. This research was undertaken to investigate the distribution and stratigraphy of scalloped depressions in Utopia Planitia and to reconstruct the past environment in which this periglacial landscape formed. To that end a revised geologic map of the region has been produced. We define, for the first time, a new Periglacial Unit, the youngest geologic unit in Utopia Planitia. We have also developed a model for the formation and evolution of the periglacial landscape examined by assessing the use of scalloped depressions as indicators of climate change, and combining our geologic evidence with recent climate model predictions. It is concluded that in the recent past Utopia Planitia has experienced an intensified regional climate and a dynamic, evolving landscape that has recorded the changing climate on Mars. Keywords Mars, Utopia Planitia, Periglacial, scalloped depressions, Climate change iv Co-Authorship Contributions to this thesis were made by Dr. Gordan Osinski, Dr. Marco Van de Wiel, and Dr. Radu Capitan. Dr. Osinski and Dr. Van de Wiel provided commentary and feedback on all thesis chapters. Dr. Capitan provided assistance with the production of the figures. Mary Kerrigan is lead author on all chapters and is primarily responsible for all research, writing, and data processing. v Table of Contents CERTIFICATE OF EXAMINATION ............................................................................... ii Keywords ........................................................................................................................... iii Co-Authorship.................................................................................................................... iv Table of Contents ................................................................................................................ v List of Tables .................................................................................................................... vii List of Figures .................................................................................................................. viii 1 Chapter 1: Introduction .................................................................................................. 1 1.1 Periglacial Landscape of Mars ................................................................................ 1 1.2 Utopia Planitia ........................................................................................................ 2 1.3 Analogue Studies .................................................................................................... 3 1.4 References ............................................................................................................... 5 2 Chapter 2: The Distribution and Stratigraphy of Periglacial Landforms in Utopia Planitia, Mars ................................................................................................................. 8 2.1 Introduction ............................................................................................................. 9 2.2 Study Area ............................................................................................................ 10 2.3 Methodology ......................................................................................................... 12 2.4 Results ................................................................................................................... 15 2.5 Interpretations and Discussion .............................................................................. 22 2.6 Conclusion ............................................................................................................ 25 2.7 References ............................................................................................................. 25 3 Chapter 3: Past Environments on Mars ........................................................................ 28 3.1 The Climate History of Mars ................................................................................ 28 vi 3.2 Geology and Climate ............................................................................................ 29 3.3 References ............................................................................................................. 29 4 Chapter 4: Scalloped Depressions as Indicators of Recent Climate Change in Utopia Planitia, Mars ................................................................................................... 31 4.1 Introduction ........................................................................................................... 32 4.2 Study Area and Methodology ............................................................................... 33 4.3 Scalloped depressions ........................................................................................... 36 4.4 Volcanic Activity .................................................................................................. 39 4.5 Climate Models ..................................................................................................... 40 4.6 Results and Discussion ......................................................................................... 43 4.7 Conclusions ........................................................................................................... 44 4.8 References ............................................................................................................. 47 5 Chapter 5: Research Conclusions and Future Work .................................................... 51 5.1 Major Findings ...................................................................................................... 51 5.2 Further Mapping in Utopia Planitia ...................................................................... 52 5.3 References ............................................................................................................. 53 Appendix ........................................................................................................................... 55 vii List of Tables Table 2.1 Summary of data sources. ................................................................................. 14 Table 4.1 Summary of some periglacial landforms and the environmental conditions they indicate.. ............................................................................................................................ 37 viii List of Figures Figure 1.1 Global topographic map of Mars ....................................................................... 2 Figure 1.2 Martian Landforms and their Earth Analogues. ................................................ 3 Figure 2.1 Global map of Mars with study area. .............................................................. 11 Figure 2.2 The Distribution of Periglacial Landforms in Utopia Planitia ........................ 15 Figure 2.3 Types of scalloped depressions ......................................................................
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