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Using Oxygen and Carbon Stable Isotopes, 53Mn-53Cr Isotope Systematics, and Petrology to Constrain the History of Carbonates

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Using Oxygen and Carbon Stable Isotopes, 53Mn-53Cr Isotope Systematics, and Petrology to Constrain the History of Carbonates University of New Mexico UNM Digital Repository Earth and Planetary Sciences ETDs Electronic Theses and Dissertations 7-10-2013 Using oxygen and carbon stable isotopes, 53Mn-53Cr isotope systematics, and petrology to constrain the history of carbonates and water in the CR and CM chondrite parent bodies Mark Tyra Follow this and additional works at: https://digitalrepository.unm.edu/eps_etds Recommended Citation Tyra, Mark. "Using oxygen and carbon stable isotopes, 53Mn-53Cr isotope systematics, and petrology to constrain the history of carbonates and water in the CR and CM chondrite parent bodies." (2013). https://digitalrepository.unm.edu/eps_etds/93 This Dissertation is brought to you for free and open access by the Electronic Theses and Dissertations at UNM Digital Repository. It has been accepted for inclusion in Earth and Planetary Sciences ETDs by an authorized administrator of UNM Digital Repository. For more information, please contact [email protected]. Mark Anthony Tyra Candidate Earth and Planetary Sciences Department This dissertation is approved, and it is acceptable in quality and form for publication: Approved by the Dissertation Committee: Adrian J. Brearley , Chairperson Ian D. Hutcheon Rhian H. Jones Zachary D. Sharp Charles K. Shearer i USING OXYGEN AND CARBON STABLE ISOTOPES, 53MN-53CR ISOTOPE SYSTEMATICS, AND PETROLOGY TO CONSTRAIN THE HISTORY OF CARBONATES AND WATER IN THE CR AND CM CHONDRITE PARENT BODIES by MARK ANTHONY TYRA B.S., Geology, University of Kentucky, 2000 M.S., Geology, University of Maryland, 2005 DISSERTATION Submitted in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy in Earth and Planetary Sciences The University of New Mexico Albuquerque, New Mexico May, 2013 ii DEDICATION Education, on the other hand, means emancipation. It means light and liberty. It means the uplifting of the soul of man into the glorious light of truth, the light only by which men can be free. To deny education to any people is one of the greatest crimes against human nature. It is to deny them the means of freedom and the rightful pursuit of happiness, and to defeat the very end of their being. –Frederick Douglass iii ACKNOWLEDGEMENTS This work is the direct result of many people who have lent their support. I first would like to thank my dissertation advisor, Dr. Adrian Brearley. His support, challenges, conversations, insight, and guidance have helped my growth as a writer and a scientist. I consider him both a mentor and a friend. I also wish to thank my dissertation committee Drs. Ian Hutcheon, Rhian Jones, Charles Shearer, and Zachary Sharp for their advice, feedback, and discussion. I also am grateful for the support of Drs. Benjamin Jacobson, Jennifer Matzel, Erick Ramon, and Peter Weber at Lawrence Livermore National Laboratory for their support and ideas. Similarly, the support of Dr. Yunbin Guan at the California Institute of Technology Center for Microanalysis was essential for much of the work presented here. At the University of New Mexico, I would like to express my sincere thanks to friends and colleges who helped in a myriad of ways. This includes Dr. Mike Spilde and Ara Kooser at the EPS Electron Microbeam Facility and Drs. Ying-Bing Jiang, Shenghong Huang, and Corentin Le Guillou in the TEM lab. Furthermore, support from the administrative staff, Mary Bennett, Mabel Chavez, Cindy Jaramillo, and Paula Pascetti, has been essential during my stay here. I also am grateful for the many colleagues and friends at the E&PS department who have helped in so many ways. I also must acknowledge my friends and family for all that they have done. I am also grateful for my parents and brother, who love a good argument, a good story, and have supported me in uncounted ways. Lastly I would like thank my wife Jennifer for her support, patience, and love throughout this process. Her support underlies every phrase in this work. iv PREFACE This work is primarily the work of the author. Each chapter, however, is the culmination of work of multiple workers and will be submitted to professional journals as multi-author works. As requested by the Department of Earth and Planetary Sciences, the input of each additional worker is noted below. Chapter 1 will be submitted as a paper with A. J. Brearley1, J. Matzel2, I. D. Hutcheon2, and E. Ramon2 as coauthors. A.J. Brearley provided data interpretation, funding, and editing. J. Matzel and E. Ramon collected NanoSIMS data and provided data interpretation. I.D. Hutcheon provided funding, editing, and data interpretation. Chapter 2 will be submitted for publication along with coauthors A. J. Brearley1, J. Matzel2, and I. D. Hutcheon2. A.J. Brearley helped design and fund the project, provided data interpretation, and edited the manuscript. J. Matzel helped collect Mn-Cr data, provided data interpretation, and edited the manuscript. I. D. Hutcheon provided funding, ideas, and editorial handling. Chapter 3 will be submitted to a journal as a multi-author paper. Adrian Brearley1 secured funding and edited this work. Yunbin Guan3 provided guidance and helped acquire isotope data using SIMS. Chapter 4 coauthors include Adrian Brearley1, who provided ideas, editing, and support, and Yunbin Guan3, who provided SIMS data and interpretation. 1Dept. of Earth and Planetary Sciences, University of New Mexico, Albuquerque, NM 87131, USA ([email protected]), 2Glenn T. Seaborg Institute, Chemical Sciences Division, Lawrence Livermore National Laboratory, Livermore, CA 94551. 3Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA 91125 v USING OXYGEN AND CARBON STABLE ISOTOPES, 53MN-53CR ISOTOPE SYSTEMATICS, AND PETROLOGY TO CONSTRAIN THE HISTORY OF CARBONATES AND WATER IN THE CM AND CR CHONDRITE PARENT BODIES by Mark Anthony Tyra B.S., Geology, University of Kentucky, 2000 M.S., Geology, University of Maryland, 2005 Doctor of Philosophy in Earth and Planetary Sciences University of New Mexico, May 2013 ABSTRACT I carried out a petrologic and Mn-Cr isotopic study of carbonates in the paired CM1 chondrites, ALH 84049 and ALH 84051, in an effort to understand the origin and chronology of formation of carbonates in the most heavily altered CM chondrites. Dolomite is strongly compositionally zoned (Ca, Mg, Fe, Mn), indicating very heterogeneous formation conditions, yet all carbonate Mn-Cr analyses form individual isochrons. In this study, I also analyzed the Mn-Cr isotope systematics of the CR1 chondrite GRO 95577 and determined that siderite is the youngest secondary mineral yet observed in carbonaceous chondrites. This has implications for the CR parent body as it either was large enough to retain heat for long periods of time or was heated by impact after most aqueous alteration in carbonaceous chondrites had ceased. This study also presents analyses of carbonates in the same samples (ALH 84049 and GRO 95577) in- situ for their oxygen, and, in ALH 84049, carbon isotope composition to constrain aqueous alteration. The results show that multiple generations of carbonates must have occurred in ALH 84049 from a carbon source with either heterogeneous carbon isotopes or with changing carbon isotope compositions from ongoing methane formation. Furthermore, in GRO 95577, the oxygen isotope values suggest that calcite precipitated before siderite if CR chondrite fluids followed a closed system oxygen isotope evolution path similar to CM chondrites. vi TABLE OF CONTENTS CHAPTER 1, Origin and chronology of formation of carbonates in the most heavily altered CM chondrites………………………………………......……………………….1 1. Abstract…………………………………….…………………………………...……..1 2. Introduction…………………………………………………….……………...………1 3. Samples and Methods……………………………………………………………...….4 3.1. Samples………………………………………………………………………..….4 3.2. Analytical Methods…………………………………………………………….…6 3.2.1. Petrographic analysis…………………………………………………..….6 3.2.2. NanoSIMS analyses…………………………………………………….....9 4. Results……………………………………………………………………………..…11 4.1. General Petrography……………………………………………………….……11 4.2. Carbonate Petrography…………………………………………………...……..13 4.2.1. Dolomite zoning and chemistry………………………………………….15 4.2.2. Dolomite major element composition……………………...…………….20 4.3. Mn-Cr isotopic systematics……………………………………………………..21 5. Discussion……………………………………………………………………...…….23 5.1. Mn-Cr Systematics……………………………………………………………...23 5.1.1. All CM1 dolomite ages are cogenetic………………………………..…..25 5.2. Composition and Petrography……………………………………………….….28 5.2.1. Total dolomite compositional variability………………………………...28 5.2.2. Chemical zoning in dolomite…………………………………………….29 5.2.3. Implications of carbonate zoning on the nature of fluid…………………32 5.2.4. Significance of veins……………………………………………………..37 6. Conclusions…………………………………………………………………………..39 7. Acknowledgements…………………………………………………………………..40 8. Bibliography…………………………………………………………………………40 vii 9. Tables………………………………………………………………………………...46 10. Figures……………………………………………………………………………..…48 11. Appendix….………………………………………………………………………….72 CHAPTER 2. Very late timing of CR1 GRO 95577 aqueous alteration: a NanoSIMS 53Mn-53Cr study of siderite……………………………………………………………..83 1. Abstract……………………………………………………………………………....83 2. Introduction………………………………………………………………………..…83 3. Samples and Methods………………………………………………………………..87 4. Results………………………………………………………………………………..89 4.1. Petrography……………………...………………………………………………89 4.1.1. Whole rock petrography…………………………………………………89 4.1.2. Carbonate petrography and chemistry…………………………………...92 4.2. Siderite Mn-Cr isotopic systematics…………………………………………….95 5. Discussion……………………………………………………………………………96
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