Japan Geoscience Union Meeting 2018

Presentation information

[JJ] Poster

S (Solid Earth Sciences) » S-VC Volcanology

[S-VC41] Active Volcanism

Wed. May 23, 2018 1:45 PM - 3:15 PM Poster Hall (International Exhibition Hall7, Makuhari Messe)

convener:Yuta Maeda(Nagoya University), Takahiro Miwa(National research institute for earth science and disaster prevention), Yosuke Aoki(東京大学地震研究所, 共同), Takeshi Nishimura(Department of Geophysics, Graduate School of Science, Tohoku University), Takahiro Ohkura(Aso Volcanological Laboratory, Institute for Geothermal Sciences, Graduate School of Science, Kyoto University), Satoshi Okumura(Division of Earth and Planetary Materials Science, Department of Earth Science, Graduate School of Science, Tohoku University), Tomofumi Kozono(Department of Geophysics, Graduate School of Science, Tohoku University)

[SVC41-P12] A Review of Eruptions at Kusatsu-Shirane Volcano ~ Especially on Jan 2018 Explosion.

*Osamu Oshima1 (1.none)

Keywords:Kusatsu-Shirane volcano, steam eruption, crater row

A steam explosion of Kusatsu-Shirane Volcano on January 23, 2018, occurred at Northern end of summit crater of Moto-Shirane Volcano that had no record of eruption in historical time. (Recent eruptions have occurred in Shirane Volcano famous for its blue crater lake, that is located 2 km north of Moto-Shirane.) The new crater row (up to 500m long) is aligned in WNW-ESE direction, that is nearly normal to the main alignment of pyroclastic volcanic bodies in Kusatsu-Shirane Volcano. The bi-axial two directions may represent the main stress field from E in this volcano area.

Video images of the new eruption shows specific characters of steam explosion with fallen blocks, lapilli, and ash without heat. In February the new small craters are covered by snow, and no one can reach there. However, there may still be a danger of leak of poisonous gas.