Construction of a multi-element XANES library of layered silicates used for water metamorphism analysis in meteorite mother celestial bodies

Abstract

Layered silicate, which is a kind of hydrous mineral that may be contained in meteorites, is a mineral produced in the presence of liquid water, and layered silicate is a variety of minerals depending on the content of structural elements and coordination position. Species exist and the mineral species of layered silicates are associated with the production environment. Therefore, it may be possible to estimate the aquatic environment of extraterrestrial celestial bodies from the mineral species of layered silicate contained in meteorite samples. In this study, we focus on ”scanning transmission electron microscope (STXM)” as a method for meteorite sample analysis. STXM is a tool for analyzing the existence of elements in local regions. That is, it is possible to understand information such as which part of the structure the element is coordinated with, and to estimate the type of layered silicate. In this study, X-ray absorption spectra of constituent elements were collected using various layered silicates on the earth as standard samples, and the obtained results were made into a library together with the sample characteristics so that they could be applied to STXM analysis of meteorite samples.