Investigating the water and volatile inventory of unequilibrated ordinary chondrites

液态水是促成太阳系生命出现的重要因素之一。因此，了解太阳系水的起源(S)是太阳系科学研究的一个活跃领域。水在太阳系中无处不在，存在于大多数行星及其卫星，以及小行星和彗星中。富含挥发分的碳质球粒陨石被认为是太阳系最原始的天体之一，因此一直是早期太阳系水研究的重点。另一方面，普通球粒陨石的挥发性清单受到的关注要少得多，尽管这些陨石在我们的陨石收藏中占绝大多数样本，可能是在类地行星形成过程中发挥重要作用的小行星类型的样本。这个项目的目标是通过限制非平衡普通球粒陨石的挥发性预算来填补这一重要的知识空白。我们将使用岩石学、地球化学和光谱技术相结合的方法调查大约15-20个非平衡普通球粒陨石的水和挥发分库存。样品的矿物学将用X射线衍射分析、红外光谱和电子束技术进行检测。将使用透射式红外光谱和二次离子质谱仪在选定的样品中测定水和其他挥发性物质(如N、S和氯)的丰度和同位素组成。这个关于普通球粒陨石中水和挥发物的原始数据集最终将允许测试我们现有的关于早期太阳系中水和挥发物的来源和处理的模型。

Liquid water is one of the vital ingredients that allowed the emergence of life in the Solar System. Therefore, understanding the origin(s) of Solar System water is an active area of Solar System science research. Water is ubiquitous in the Solar System, and is present in most of the planets and their satellites, as well as asteroids and comets. The volatile-rich carbonaceous chondrite meteorites are thought to constitute some of the most primitive Solar System objects, and have thus been the focus of most of the studies on water in the early Solar System. On the other hand, the volatile inventory of ordinary chondrite meteorites has received much less attention, despite the fact that these meteorites, which represent the large majority of samples in our meteorite collections, probably sample asteroid-types that played an important role during formation of terrestrial planets. The goal of this project is to fill this important knowledge gap by constraining the volatile budget of unequilibrated ordinary chondrites.We will investigate the water and volatile inventory of around 15-20 unequilibrated ordinary chondrite meteorites using a combination of petrological, geochemical and spectroscopic techniques. The mineralogy of the samples will be examined using XRD analysis, infrared spectroscopy and electron beam techniques. The abundance and isotopic composition of water and other volatile species (e.g., N, S, and Cl) will be determined in selected samples using transmission infrared spectroscopy and secondary ion mass spectrometry. This original dataset obtained on water and volatiles in ordinary chondrite meteorites will eventually permit testing of our existing models for the origin and processing of water and volatiles in the early Solar System.