par Massant, Anicée 
Président du jury Mattielli, Nadine
Promoteur Debaille, Vinciane
Co-Promoteur Thiemens, Maxwell
Publication Non publié, 2021-08-27
Président du jury Mattielli, Nadine
Promoteur Debaille, Vinciane
Co-Promoteur Thiemens, Maxwell
Publication Non publié, 2021-08-27
Mémoire
| Résumé : | The Moon accreted from the aftermath of an impact into the proto-Earth. The early Moon was in a largely or completely molten state, covered in a Lunar Magma Ocean (LMO). As the LMO crystallized, it formed different reservoirs of rock types, the low Ti basalts, high Ti basalts, an anorthositic crust, and an incompatible element enriched layer. Eventually, these all mixed. Tracing the evolution of these reservoirs requires the analysis of as many samples as possible. The primary aim of this study is to - as thoroughly as possible - analyze the petrological and mineralogical composition of the brecciated lunar meteorite NWA11474. Our goal is to thoroughly categorize the constituent components of the meteorite in order to trace their source origins. To do this, we first use micro-x-ray fluorescence (μ-XRF) to determine the element composition of the constituent clasts in-situ. Then, we perform mineral separation by hand picking to assess the composition of the individual chemical composition of each mineral type. We analyze the trace elements concentration of these separates using an Agilent ICP-mass spectrometer and an Element2 HR-ICP-mass spectrometer. Finally, we analyze the major elements concentration using an iCAP ICP-optical emission spectrometer. The result of these analysis suggests that NWA11474 is a brecciated lunar feldspathic meteorite with at least part present a variable enrichment in KREEP-poor Mg-suite components and which would have originated from the Feldspathic Highland Terrane. |
