著者

纐纈 佑衣

出版者

一般社団法人 日本鉱物科学会

雑誌

岩石鉱物科学 (ISSN:1345630X)

巻号頁・発行日

pp.230110a, (Released:2023-04-13)

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Spectroscopy has been widely used in geology since the 1990s because it is non-destructive and easy to analyze. Raman spectroscopy has generally been used to identify mineral phases in geology, but recent studies have proposed new methods to quantitatively estimate the metamorphic pressure (quartz Raman barometry) and peak temperature (Raman carbonaceous material geothermometry). Studies using infrared spectroscopy are also underway to advance our understanding of hydration processes in subduction zones and mantle through the analysis of water in rocks. In addition to the development of new methods using spectroscopy, new tools are also being developed to analyze huge amounts of data through iterative processing, which will enable the extraction of more informative and quantitative results in a shorter time. This paper introduces examples of spectroscopy applications in geology and examines future developments.

著者

角野 浩史 ウォリス サイモン 纐纈 佑衣 遠藤 俊祐 水上 知行 吉田 健太 小林 真大 平島 崇男 バージェス レイ バレンティン クリス

出版者

一般社団法人日本地球化学会

雑誌

日本地球化学会年会要旨集

巻号頁・発行日

vol.64, 2017

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<p>四国中央部・三波川変成帯に産する変泥質岩、エクロジャイト、蛇紋岩、かんらん岩のハロゲン・希ガス組成は一様に、深海底堆積物中の間隙水と非常によく似た組成を示す。同様の組成は島弧火山岩中のマントルかんらん岩捕獲岩や深海底蛇紋岩でも見られることから、沈み込み前に屈曲したプレートの断層沿いにプレート深部に侵入した間隙水がスラブマントルを蛇紋岩化する際に、ハロゲンと希ガスが組成を保ったまま蛇紋岩に捕獲されて沈み込み、水とともにウェッジマントルへと放出されている過程が示唆される。</p>

著者

纐纈 佑衣 冨岡 優貴 西山 忠男 榎並 正樹

雑誌

一般社団法人日本鉱物科学会2021年年会・総会

巻号頁・発行日

2021-08-11

著者

金木 俊也 中村 佳博 纐纈 佑衣 向吉 秀樹

雑誌

JpGU-AGU Joint Meeting 2020

巻号頁・発行日

2020-03-13

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Carbonaceous material (CM) is widely distributed in sedimentary and metamorphic rocks, and its thermal maturity and crystallinity have been used as an indicator of burial and metamorphic temperature history. The relationship between maturity and temperature history of CM has been documented by various analytical techniques, including X-ray diffraction measurements, vitrinite reflectance measurements, transmission electron microscopy, infrared spectroscopy, and Raman spectroscopy. Among these, Raman spectroscopy is increasingly being used because of its rapidness and usefulness, as well as it is normally non-destructive technique (Henry et al., 2019).A typical Raman spectrum of CM exhibits two distinct peaks of D (around 1350 cm–1) and G bands (around 1580 cm–1) (Tuinstra & Koenig, 1970). Various spectral parameters, which is associated with the thermal maturity of CM, are reported; e.g., intensity ratio and full-width at half maximum (FWHM) of D and G bands. Importantly, there are mainly two types in these spectral parameters: (1) parameters calculated from raw data, or (2) parameters calculated by performing spectral fitting. One of the representative parameters of the latter was proposed by Beyssac et al. (2002). Because it is argued that their R2 ratio (area of G band / area of D1+D2+G bands) is closely related to the CM maturity, numerous studies adopted the R2 ratio as a representative parameter of Raman spectra of CM (e.g., Kouketsu et al., 2014). On the other hand, Henry et al. (2018) suggested that spectral fitting should not be performed because it leads to unnecessary errors, and recommended to focus on the parameters that can be calculated from the raw spectrum without spectral fitting.In the light of these backgrounds, the final goal of this study is to investigate whether spectral fitting of Raman spectra of CM is useful to evaluate its thermal maturity. As a first step toward this purpose, we developed a Python script that automatically perform spectral fitting of Raman spectra of CM. Analytical procedures of the script mainly consist of 5 parts: (i) smoothing by Savitzky-Golay filtering method, (ii) background correction with 1st or 3rd order polynomial function, (iii) normalization, (iv) setting of initial spectral parameters, and (v) non-linear spectral fitting with pseudo-Voigt function. We analyze the published data of Raman spectra of CM by Kouketsu et al. (2014), Mukoyoshi et al. (2018), and Nakamura et al. (2019), and compared the calculated parameters with the reported values of vitrinite reflectance. We will show preliminary results of our attempts in this presentation.