Last Update 05/19 2016
Research: I am interested in the evolution of magma plumbing system beneath volcanoes. The questions I am attempting to answer are: What depth do magmas stagnate beneath volcanoes? How do their chemical compositions change during the life-time of volcanoes? I think the concentration of volatiles, especially water, in magma is most influential factor to control the evolution of magma plumbing system. And thus I have engaged in the measurement of water in magma by means of analyses on melt-inclusions in these years. With regards to this issue, I have developed a new method to measure water concentration on small volcanic glass by FTIR reflectance micro spectroscopy. I am also interested in the field of computer-aided geoscience. The world wide web (WWW) is a powerful user-interface for handling a variety of geological and geophysical data. As a co-operative study with VRC, we have launched several web sites to help to recognize volcanic activity as quickly as possible (e.g., http://magma.eri.u-tokyo.ac.jp/intro.html; http://vrsserv.eri.u-tokyo.ac.jp/REALVOLC/indexJ.html), and I have written many scripts to maintain the sites. Publications: Yasuda, A., Fujii, T, Application of a solid-electrolyte oxygen fugacity sensor to high-pressure experiment, Phys. Earth Planet. Inter., 80, 49--64, 1993. Yasuda, A., Fujii, T., Kurita, K., Melting pahse relations of an anhydrous mid-ocean ridge basalt from 3 to 20 GPa: Implications for the behavior of subducted oceanic crust in the mantle, J. Geophys. Res., 99, 9401--9414, 1994. Yasuda, A., T. Fujii, and K. Kurita, A composite diapir model for extensive basaltic volcanism: Magmas from subducted oceanic crust entrained within mantle plumes, Proc. Japan Acad. Ser. B, 73, 10, 201--204, 1997. Yasuda, A., and T. Fujii, Ascending subducted oceanic crust entrained within mantle plumes, Geophys. Res. Lett., 25, 10, 1561--1564, 1998. 安田 敦・中田節也・藤井敏嗣, 三宅島2000年噴火噴出物のmelt inclusionに記録されたマグマのS濃度とfO2環境, 火山, 46, 4, 165--173, 2001. 安田 敦, 顕微FT-IR反射分光法による斑晶ガラス包有物の含水量測定, 火山, 56, 2-3, 41--49, 2011. 安田 敦・金子隆之・新堀賢志・藤井敏嗣, ユーザーインターフェイスを改良した溶岩流シミュレーションシステムとその防災上の意義, 火山, 58, 2, 379--385, 2013. Atsushi YASUDA, A new technique using FT-IR micro-reflectance spectroscopy for measurement of water concentrations in melt inclusions, Earth Planets Space, 66, DOI: 10.1186/1880-5981-66-34, , 2014. 安田 敦・吉本充宏・藤井敏嗣, 姶良火砕噴火のマグマ溜まり深度, 火山, 60, 3, 381--397, 2015. 安田 敦, プルームを読む（川勝均編「地球科学の新展開１：地球ダイナミクスとトモグラフィー」，p161-189）, 朝倉書店, 2002. |
