著者

石村 豊穂

出版者

一般社団法人日本地球化学会

雑誌

地球化学 (ISSN:03864073)

巻号頁・発行日

vol.55, no.3, pp.63-86, 2021-09-25 (Released:2021-09-25)

参考文献数

75

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Stable carbon and oxygen isotopic compositions (δ13C, δ18O) of carbonates, especially calcium carbonate (CaCO3), have been utilized in geochemical research for more than 60 years because the isotopic values record environmental history at the time of formation. In particular, the stable isotopic compositions of biogenic carbonate record the δ18O (salinity variation and global ice volume) and temperature history of ambient seawater, as well as the δ13C of dissolved inorganic carbon (DIC), which is important as basic information for elucidating carbon cycles and mechanism of environmental changes. In recent years, isotopic analysis of carbonate has been expected to improve the sensitivity for high-resolution environmental analysis, but the progress of analytical techniques has been limited. In such a situation, improvements in the sample preparation and introduction system for stable isotope ratio mass spectrometry (IRMS) have made it possible to determine the stable isotopic composition of carbonate less than 1/100 of the sample amount required by previously reported systems (MICAL: Ishimura et al., 2004, 2008b).In this paper, I described the current progress and problems of stable isotopic analysis of carbonate, then explain the details of the development of analytical method for carbonate in ultra-micro scale, and the applications to various research fields.