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A Tool to Constrain Early Parent Body Hydrothermal Processes

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A Tool to Constrain Early Parent Body Hydrothermal Processes Microbeam characterization of volatile-rich clasts - a tool to constrain early parent body hydrothermal processes A Dissertation Submitted in Partial Fulfilment of the Requirements for the Degree of Doktor der Naturwissenschaften (Dr. rer. nat.) to the department of Earth Sciences of the Freie Universität Berlin by Robbin Visser Berlin, September 2019 Gutachter: Prof. Dr. Timm John Prof. Dr. Addi Bischoff Disputationsdatum: 08.11.2019 ii Erklärung der Eigenständigkeit Hiermit versichere ich, dass ich die vorliegende Arbeit selbstständig verfasst und keine anderen als die angegebenen Quellen und Hilfsmittel benutzt habe; alle Ausführungen, die anderen Schriften wörtlich oder sinngemäß entnommen wurden, kenntlich gemacht sind und die Arbeit in gleicher oder ähnlicher Fassung noch nicht Bestandteil einer Studien- oder Prüfungsleistung war. Berlin, iii Table of contents Summary ..................................................................................................................................... v Zusammenfassung ...................................................................................................................... vii Chapter 1 - Introduction .............................................................................................................. 1 1.1 This thesis in the TRR170 framework .................................................................................................. 2 1.2 Distribution of highly volatile elements during solar system formation ................................................. 3 1.3 Meteoritic breccias ............................................................................................................................... 4 1.4 Volatile-rich clasts ................................................................................................................................ 5 1.5 Aim of the thesis................................................................................................................................... 8 1.6 Scientific chapters ................................................................................................................................. 8 1.7 References .......................................................................................................................................... 10 Chapter 2 - Temperature constraints by Raman spectroscopy of organic matter in volatile-rich clasts and carbonaceous chondrites .................................................................................... 14 Abstract .................................................................................................................................................... 15 2.1 Introduction ....................................................................................................................................... 16 2.2 Methods ............................................................................................................................................. 19 2.3 Results................................................................................................................................................ 26 2.4 Discussion .......................................................................................................................................... 30 2.5 Conclusions ....................................................................................................................................... 39 2.6 Acknowledgements ............................................................................................................................. 40 2.7 References .......................................................................................................................................... 41 Chapter 3 - Sulfur isotope study of sulfides in CI, CM, C2ung chondrites and volatile-rich clasts - evidence for different generations and reservoirs of sulfide formation ................................. 47 Abstract .................................................................................................................................................... 48 3.1 Introduction ....................................................................................................................................... 48 3.2 Methods and samples ......................................................................................................................... 50 3.3 Results................................................................................................................................................ 52 3.4 Discussion .......................................................................................................................................... 58 3.5 Conclusions ....................................................................................................................................... 66 3.6 Acknowledgements ............................................................................................................................. 67 3.7 References .......................................................................................................................................... 67 Chapter 4 - A short-lived 26Al induced hydrothermal alteration event in the outer solar system: Constraints from Mn/Cr ages of carbonates ....................................................................... 71 Abstract .................................................................................................................................................... 72 4.1 Introduction ....................................................................................................................................... 72 4.2 Methods ............................................................................................................................................. 74 4.3 Results................................................................................................................................................ 76 4.4 Discussion .......................................................................................................................................... 79 4.5 Conclusion ......................................................................................................................................... 87 4.6 Acknowledgements ............................................................................................................................. 87 4.7 References .......................................................................................................................................... 87 Chapter 5 - Conclusions ............................................................................................................. 91 Chapter 6 - Outlook ................................................................................................................... 94 Appendix 1 - Thesis-related publications .................................................................................... 96 Appendix 2 - Meteorite list ......................................................................................................... 98 Appendix 3 - Supplement tables and figures .............................................................................. 104 Supplements chapter 2 ........................................................................................................................... 105 Supplements chapter 3 ........................................................................................................................... 106 Supplements chapter 4 ........................................................................................................................... 122 Curriculum Vitae ..................................................................................................................... 130 Acknowledgements ................................................................................................................... 133 iv Summary Meteoritic breccias can contain material that is not yet available in current meteorite collections as individual rocks. These materials can significantly contribute to answering questions related to the formation, environment, and evolution history of planetary bodies. Volatile-rich clasts are a great example of material that occurs in brecciated meteorites and can be used to answer questions related to the above mentioned topics. Volatile-rich clasts in general are characterized by abundant volatile-bearing secondary formed minerals and can be subdivided into two main types: 1) The CM-like type, which contains chondrules with accretionary rims, tochilinite-cronstedtite intergrowths (TCI), carbonates, and Fe-Ni sulfides dispersed in a very fine phyllosilicate matrix. 2) The CI-like type clasts that contain a fine-grained phyllosilicate matrix with embedded magnetite, Fe-Ni sulfides, carbonates, accessory minerals, and very rarely chondrules or fragments of them. The mineralogy of the two types of clasts shows a strong association to the well-known CM and CI chondrites, respectively. However, it is unclear whether the volatile-rich clasts are actually similar to the analogue chondrites or whether they represent material that is not yet present in our meteorite collections. The goal of this thesis is to not only characterize the volatile-rich clasts and investigate the differences between the clasts and the chondrites, but also to obtain a
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