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MacArtney, Adrienne (2018) Atmosphere crust coupling and carbon sequestration on early Mars. PhD thesis. http://theses.gla.ac.uk/9006/ Copyright and moral rights for this work are retained by the author A copy can be downloaded for personal non-commercial research or study, without prior permission or charge This work cannot be reproduced or quoted extensively from without first obtaining permission in writing from the author The content must not be changed in any way or sold commercially in any format or medium without the formal permission of the author When referring to this work, full bibliographic details including the author, title, awarding institution and date of the thesis must be given Enlighten:Theses http://theses.gla.ac.uk/ [email protected] ATMOSPHERE - CRUST COUPLING AND CARBON SEQUESTRATION ON EARLY MARS By Adrienne MacArtney B.Sc. (Honours) Geosciences, Open University, 2013. Submitted in partial fulfilment of the requirements for the degree of Doctor of Philosophy at the UNIVERSITY OF GLASGOW 2018 © Adrienne MacArtney All rights reserved. The author herby grants to the University of Glasgow permission to reproduce and redistribute publicly paper and electronic copies of this thesis document in whole or in any part in any medium now known or hereafter created. Signature of Author: 16th January 2018 Abstract Evidence exists for great volumes of water on early Mars. Liquid surface water requires a much denser atmosphere than modern Mars possesses, probably predominantly composed of CO2. Such significant volumes of CO2 and water in the presence of basalt should have produced vast concentrations of carbonate minerals, yet little carbonate has been discovered thus far. These ‘missing carbonates’ comprise the Mars carbonate conundrum. This thesis provides insight to the conundrum via three distinct lines of investigation. Firstly, using engineering to expand our ability to locate carbonates on the Martian surface. A Micro-Optic UltraSonic Exfoliator (MOUSE) was designed and built that was tested on a range of rock types and wavelengths. Using ultrasonics demonstrates many advantages over the rock abrasion tool currently used on Mars rovers, including a smoother grind finish and a lower rate of tool tip wear when using tungsten carbide. Secondly, carbonates present in our only samples of the Martian regolith on Earth, meteorites, were studied. Carbonates found in Martian meteorites can provide a record of aqueous and atmospheric conditions extending back over 4.5 billion years. This thesis observes carbonates in two meteorites, ALH 84001 and Lafayette, representing early Mars and more recent Mars respectively, and finds evidence for two types of carbonate replacing glass in ALH 84001. The aqueously altered minerals of these two meteorites were compared with those found in the terrestrial ophiolites of Leka (Norway), and Semail (United Arab Emirates), and these ophiolites were assessed for suitability as Mars analogues. Chemically zoned carbonate rosettes similar to those in ALH 84001 are found in the Semail ophiolite samples. No carbonates were identified in Leka samples, but extensive serpentinisation was present. Finally, this thesis sought to replicate alteration processes and products that are recorded by Martian meteorites within a Mars analogue laboratory environment. The effects of differing initial atmospheric and mineral compositions were explored, specifically the comparison of CO2 and SO2 with basalt versus CO2 with olivine. These three interdisciplinary strands of investigation provide some novel tools, ideas and evidence to help solve the Mars carbonate conundrum. Page | 2 Dedication This PhD is dedicated to Debbie Brown Where it all began. And to a rabbit who looked after me. Page | 3 Acknowledgements This work was funded by the UK Space Agency (UKSA) through the Science and Technologies Facilities Council (STFC). I hope most sincerely that this thesis is a good return on their investment in me, and that they might be proud of its contribution to the fields of space engineering and geochemistry. I would like to thank my supervisors, Professor Martin Lee and Dr Patrick Harkness, for offering me the opportunity to research such a fantastic project, engaging in climate challenges both terrestrial and Martian. Their ongoing support, advice and wisdom have been invaluable in helping navigate the politics and intricacies of early career academia. Keith Bateman and Dr Chris Rochelle from the British Geological Survey have my deepest appreciation for equipment provision, laboratory space, ICPMS processing, extensive technical advice and proof reading of chapter 4. Gratitude is also extended to John Faithful from the Huntarian museum, Glasgow, for supplying many mineral samples, and ongoing encouragement. Essential engineering collaboration was provided by Dr Xuan Li. Further, appreciation to Peter Chung, from the school of geographical and Earth sciences, University of Glasgow, for scanning electron microscope support, and thin section support by John Gileece. I would also like to thank the staff at the CARBFIX project in Iceland for the site tour, discussions and highlighting the SULFIX work to me. An amaze balls thank you to Dr Caroline Smith from the Natural History museum, London, for ongoing loans of Mars meteorite samples. Semail ophiolite samples were kindly donated by Dr Alicja Lacinsk. Thank you to Dr Elisabeth Streit Falk, Pol Knops, Loredana Bessone, Professor Charles Cockell, Professor Martin McCoustra, Dr Mario Toubes, Tasha Nicholson, Dr Claire Cousins, Jane MacArthur, Dr Paul Niles, Dr Susan Fitzer, Dr Zita Martins, Ania Losiak, Sapphire Wanmer, Dr Florent Caste, Dr Natasha Vasiliki Almeida, Lotta Kemppinen, Dr Terry-Ann Suer, Kristin Johnson, Dr Rebecca Skuce, Dr Jaime Toney and Dr Charity Phillips-Lander for all their assistance; from Page | 4 discussions on minerals, ophiolites and space exploration, to giving a hug and a space to cry. Good advice, friendship, support, coffee and ice cream have come from a number of people; principally, Robert MacDonald (the big yin), Professor Susan Waldron, Bevis Evans Teush (my partner at Wild Orbit Films), Kenny Roberts, Kirsty Shona Hill and Dr Cristina Persano. A beautiful Jewel deserves my thanks, and fellow jail mate Nick Thomas has been a mainstay of affection, support, patience and loving kindness. I am also grateful to my mother, Margaret, for proof reading many pages of troublesome rock and mineral names, and supporting me when it all got harsh and tiresome. I would also have struggled more than I did without the practical and emotional support of Mike Cavin, the wee rabbit. Thanks also to Steve Webster, for providing me space, shelter and fine single malt in a remote Hebridean croft, where many of these pages were written. I also remember that I would not have a PhD, nor even a BSc, if it were not for the financial support of the Open University, the patient guidance and care of Alison Tossell, and the friendship of Steph Patterson, Shana Ellis, Cindy Courtillier and especially Tammy Michelle, along with the love of Deb Patterson. My unapologetic background prior to the PhD was sex work. Without the friendship, laughter, affection, cocktails and enormous support of a great many sex workers who will go unnamed, I would not have held together and achieved what I have. They are my family, and will always have my open and vociferous support. It is important to never forget where you come from. I would also like to acknowledge the encouragement of all the Science Hooker followers: the encouragement really makes all the difference. A final, sparkling, super special thank you to Dr Sarah Rugheimer, an intellectual fireball glued together with love, compassion and care. I hope all PhD students are fortunate enough to find such a valuable and supportive inspiration to guide them through the research rocks, and provide bridges into further academia. For anyone I may have inadvertently left out, it is due to my temporary myopic absorption, and not due to any lack of love or appreciation. Page | 5 Thesis contents Page Chapter 1: 7 – 71 Introduction. Chapter 2: 72 – 153 The effects of ultrasonics on Mars rover rock abrasion tool performance. Chapter 3: 154 – 274 Terrestrial ophiolite carbonates as Martian analogues. Chapter 4: 275 – 389 Experimental reproduction of Martian type carbonates and clays. Chapter 5: 390 – 405 Conclusions. Appendix 1: 406 – 419 Mineral spectral data. Appendix 2: 420 Rock abrasion tool stepper motor Arduino code. Appendix 3: 421 – 435 Scanning Electron Microscope Standards. Appendix 4: 436 – 463 Quantitative Scanning Electron Microscope analysis. Appendix 5: 464 – 481 IC – ICPMS data. Appendix 6: 482 – 485 Saturation indices. Page | 6 Chapter 1 Introduction. Page | 7 Introduction contents. Page 1.1 The Mars carbonate conundrum. 9 - 12 1.2 What are carbonate minerals? 13 - 20 1.2.1 Carbonate mineral structure and classification. 13 - 15 1.2.2 Carbonate mineral formation processes. 16 - 19 1.2.3 Importance of carbonate minerals for planetary evolution. 19 - 20 1.3 Terrestrial warming and carbon sequestration: 20 - 28 lessons from Mars. 1.4 Mineral and landed mission maps of Mars. 28 - 33 1.5 Solution to the Mars carbonate conundrum 1: 34 - 35 Locating Mars carbonates. 1.6 Solution to the Mars carbonate conundrum 2: 36 - 38 Terrestrial analogues. 1.7 Solution to the Mars carbonate conundrum 3: 38 - 45 Experimental mineralogy. 1.7.1 Experiments replicating Mars: Water. 41 1.7.2 Experiments replicating Mars: Olivine and CO2. 42 - 44 1.7.3 Experiments replicating Mars: Sulphur. 44 - 45 1.8 The structure of the thesis. 45 - 55 1.8.1 Effects of ultrasonics on rover rock abrasion 46 - 47 tool performance. 1.8.2 Terrestrial ophiolites as Mars carbonation analogues. 48 - 51 1.8.3 Experimental reproduction of Martian type carbonates 51 - 53 and clays. 1.9 References. 53 – 70 Page | 8 1.1 The Mars carbonate conundrum. Evidence exists for great volumes of water on early Mars. Liquid surface water requires a much denser atmosphere than modern Mars possesses, probably predominantly composed of CO2.