Report on Kirishimayama (Japan) — 27 June-3 July 2018
Smithsonian Institution / US Geological Survey
Weekly Volcanic Activity Report, 27 June-3 July 2018
Managing Editor: Sally Sennert.
Please cite this report as:
Global Volcanism Program, 2018. Report on Kirishimayama (Japan) (Sennert, S, ed.). Weekly Volcanic Activity Report, 27 June-3 July 2018. Smithsonian Institution and US Geological Survey.
31.934°N, 130.862°E; summit elev. 1700 m
All times are local (unless otherwise noted)
JMA reported that at Shinmoedake (Shinmoe peak), a stratovolcano of the Kirishimayama volcano group, an event at 1534 on 27 June generated a plume that rose 2.2 km above the crater rim. The report stated that since the beginning of May the rate of deformation had slowed, and tiltmeter data showed no change. In addition, sulfur dioxide emissions had decreased from 1,000 tons/day on mid-March to 80 tons/day on 1 June. On 28 June the Alert Level was lowered to 2 (on a scale of 1-5).
Geological Summary. Kirishimayama is a large group of more than 20 Quaternary volcanoes located north of Kagoshima Bay. The late-Pleistocene to Holocene dominantly andesitic group consists of stratovolcanoes, pyroclastic cones, maars, and underlying shield volcanoes located over an area of 20 x 30 km. The larger stratovolcanoes are scattered throughout the field, with the centrally located Karakunidake being the highest. Onamiike and Miike, the two largest maars, are located SW of Karakunidake and at its far eastern end, respectively. Holocene eruptions have been concentrated along an E-W line of vents from Miike to Ohachi, and at Shinmoedake to the NE. Frequent small-to-moderate explosive eruptions have been recorded since the 8th century.