Isotope Planetology Inaugural-Dissertation zur Erlangung des Doktorgrades der Mathematisch-Naturwissenschaftlichen Fakultät der Universität zu Köln vorgelegt von Maxwell Marzban Thiemens aus San Diego Köln, 2018 Berichterstatter Prof. Dr. Carsten Münker (Gutachter) Dr. Dominik Hezel Tag der mündlichen Prüfung: 11.1.19 A process cannot be understood by stopping it. Understanding must move with the flow of the process, must join it and flow with it. Dune By F. Herbert 1965 Table of Contents Table of Contents .................................................................................................................................. 5 1.0 Acknowledgements .................................................................................................................. 7 2.0 Overview ................................................................................................................................... 9 2.1 Abstract ............................................................................................................................... 10 2.2 Zussamenfassung ................................................................................................................ 12 3.0 Introduction ............................................................................................................................ 15 3.1 Early Solar System Evolution .............................................................................................. 16 3.2 Lunar Genesis ...................................................................................................................... 19 3.3 The Lunar Magma Ocean .................................................................................................... 23 3.4 Lunar Isotopic Composition ................................................................................................ 30 3.5 From Earth’s formation to mantle rocks from the Eifel ..................................................... 33 3.6 Motivation and Objectives ................................................................................................. 39 4.0 Isotopic investigations of peridotites from the West Eifel Volcanic Field .............................. 44 4.1.0 Introduction .................................................................................................................... 45 4.1.1 Background ..................................................................................................................... 45 4.1.2 Geological Setting ........................................................................................................... 48 4.2.1 Methods and Samples .................................................................................................... 51 4.3.0 Results ............................................................................................................................. 52 4.3.1 Microprobe Analysis ....................................................................................................... 52 4.3.2 Isotope Analyses ............................................................................................................. 55 4.4.0 Discussion ....................................................................................................................... 62 4.4.1 Direct chronological information - mineral isochrons and model ages ......................... 62 4.4.2 Indirect chronological information from recently reset peridotites .............................. 64 4.5.0 Conclusions ..................................................................................................................... 66 5.0 Isotope dating of lunar meteorite NWA 6950 ........................................................................ 72 5.1.0 Introduction .................................................................................................................... 73 5.2.0 Methods .......................................................................................................................... 76 5.3.0 Results ............................................................................................................................. 78 5.4.0 Discussion ....................................................................................................................... 82 5.4.1 The age of NWA 6950 ..................................................................................................... 82 5.4.2 Age spectra within the NWA 773 clan ............................................................................ 84 5.4.3 NWA 6950 and the evolution of (ur)KREEP .................................................................... 86 5.4.4 NWA 6950 representing KREEP evolution ...................................................................... 89 5.4.5 Differing model ages ....................................................................................................... 90 5.5.0 Conclusions ..................................................................................................................... 92 6.0 New Evidence for an Old Moon .............................................................................................. 94 6.1.0 Introduction .................................................................................................................... 95 6.2.0 Methods and Results ...................................................................................................... 97 6.2.1 Sample selection ............................................................................................................. 97 6.2.2 Sample Preparation ........................................................................................................ 98 6.2.3 Analytical protocols ............................................................................................................. 103 6.2.4 Results - modeling constraints ..................................................................................... 104 6.2.5 Lunar Magma Ocean fractionation and partial melting modeling ............................... 105 6.2.6 Results........................................................................................................................... 107 6.4.0 Discussion ..................................................................................................................... 108 6.5.0 Conclusions ................................................................................................................... 115 Appendix 1.0 Lunar Samples Gallery .......................................................................................... 119 A1.1 Apollo 11 ........................................................................................................................... 120 A1.2 Apollo 12 ........................................................................................................................... 121 A1.3 Apollo 13 ........................................................................................................................... 123 A1.4 Apollo 14 ........................................................................................................................... 123 A1.5 Apollo 15 ........................................................................................................................... 124 A1.6 Apollo 16 ........................................................................................................................... 126 A1.7 Apollo 17 ........................................................................................................................... 127 Appendix 2.0 References ............................................................................................................ 130 Appendix 3.0 Erklarung ............................................................................................................... 155 Appendix 4.0 Curriculum Vitae: .................................................................................................. 156 1.0 Acknowledgements I gratefully acknowledge funding from the ERC grant 669666 “Infant Earth” to Carsten Münker and SP1385 1/1 to Peter Sprung. This work wouldn’t have been possible without the Apollo samples provided by CAPTEM, or by Northwest Africa 6950, provided by Randy Korotev. Without these the work would not have been possible. Chronologically, of course, it is prudent to thank my parents first. Both Mom and Dad encouraged me towards study and the application of this from t0 was the most fundamental help towards the writing of this thesis. Thank you both for everything you have done. The skills applied to this thesis have similarly been developed over time. Dr. Schuller’s lab was the first I worked in, and I learned fundamental presentation skills (as well as some computer programming). I then learned lab etiquette with Dr. Kummel, for which I greatly owe thanks to him and the team of welcoming graduate students in his lab. Dr. Keating’s lab was where I spent the most time, and where I learned how to deal with students, bureacracy, and failed experiments. Dr. Renbarger was my mentor, and continued to provide advice for years after I left the lab. This thesis is built upon the foundation you all made. I would still be floundering through physics if Dr. Moynier had not suggested I try isotope chemistry. While the projects themselves had their own hiccups, I am incredibly appreciative for the opportunity he gave me. Similarly, my subsequent