JDR Vol.15 No.1 pp. 53-56
doi: 10.20965/jdr.2020.p0053


Air-Fall Ash from the Main Crater of Asama Volcano on August 7, 2019, and its Water-Soluble Components

Muga Yaguchi*,†, Akihiko Terada**, and Yasuo Ogawa**

*Volcanology Research Department, Meteorological Research Institute, Japan Meteorological Agency
1-1 Nagamine, Tsukuba, Ibaraki 305-0052, Japan

Corresponding author

**Volcanic Fluid Research Center, School of Science, Tokyo Institute of Technology, Tokyo, Japan

August 23, 2019
November 5, 2019
February 1, 2020
Mt. Asama volcano, volcanic ash, water-soluble components

We collected volcanic ash immediately following the eruption of Mt. Asama on August 7, 2019, observed the characteristics of ash particles, and analyzed the water-soluble components. The volcanic ash consisted mostly of altered fragments, and no clear evidence of essential materials was found. The volcanic ash contained large amounts of water-soluble components, Cl and SO4 at concentrations of 8,710 mg/kg and 49,100 mg/kg, respectively. These results indicate that this eruption was caused by the phreatic explosion and that part of the volcanic edifice of Mt. Asama was fractured and emitted.

Cite this article as:
Muga Yaguchi, Akihiko Terada, and Yasuo Ogawa, “Air-Fall Ash from the Main Crater of Asama Volcano on August 7, 2019, and its Water-Soluble Components,” J. Disaster Res., Vol.15, No.1, pp. 53-56, 2020.
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Last updated on Jan. 15, 2021