Understanding the effects of thermal metamorphism on the water and organic contents of primitive carbonaceous chondrites

科学背景热蚀变对地球上和地球外物质中有机物的结构、浓度和化学性质的影响已得到研究（1、2）。本研究旨在提供这些过程的影响，以确定岩石的原始组成，并妥善解决其有机物和挥发物的前体材料的性质的定量说明。这项研究为正在进行的样品返回太空任务Hayabusa 2和OSIRIS-REx提供了重要的见解，因为它们对加热的小行星进行了采样，而监督员（Chan，King）则在样品分析小组中。研究方法成功的候选人将进行加热实验，并观察陨石和富含有机物的泥岩的矿物学和有机物含量在加热时如何变化。样品的矿物学、化学、同位素和有机成分的数据将通过X射线衍射分析（XRD）、扫描电子显微镜（SEM）、红外、拉曼光谱、纳米二次离子质谱（NanoSIMS）和金刚石光源的X射线吸收近边结构（XANES）等技术获得。

Scientific backgroundThe effects of thermal alteration on the structure, concentration and chemistry of organic matter have been studied in both terrestrial and extra-terrestrial material (1,2). This study aims at providing a quantitative account of the impact of these processes in order to determine the primordial composition of the rocks, and to properly address the nature of the precursor material of their organics and volatiles. This study offers crucial insights into the ongoing sample-return space missions, Hayabusa2 and OSIRIS-REx, as they sample heated asteroids, while the supervisors (Chan, King) are on the sample analysis teams. Research methodology The successful candidate will conduct heating experiments, and observe how the mineralogy and organic content of meteorites and organic-rich mudrocks change when subjected to heating. Data of the mineralogy, chemical, isotopic and organic compositions of the samples will be acquired by techniques such as X-ray diffraction analysis (XRD), scanning electron microscopy (SEM), infrared, Raman spectroscopy, nanoscale secondary ion mass spectrometry (NanoSIMS), and X-ray absorption near edge structure (XANES) at Diamond Light Source.