Introduction to Automated Tools for the Analysis of Volcanic Ejecta Built on an Analysis Platform Developed in the INeVRH Project
Atsushi Yasuda and Natsumi Hokanishi
Earthquake Research Institute, The University of Tokyo
1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-0032, Japan
Volcanic activity is diverse. Therefore, a lot of volcanic ejecta need to be analyzed to properly assess the condition of a volcano. However, until now, rapid analysis in this regard has been insufficient. To accurately evaluate both the transition and the characteristics of eruptions, we constructed a platform to efficiently analyze volcanic ejecta incorporating a number of automatic processing functions into a data processing system composed of an electron beam microprobe analyzer (EPMA) and personal computers. A number of time-consuming tasks, such as crystal size distribution analysis and ash particle classification, were automated. Further, the analysis platform is equipped with a database function for collecting various analytical data as the basis for the future development of volcanology. Various quantitative values related to the composition and microtexture of the volcanic ejecta were collected and entered into the database. This paper introduces an outline of the system, collected data, and usage examples.
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