Report on Kirishimayama (Japan) — 24 February-2 March 2021
Smithsonian Institution / US Geological Survey
Weekly Volcanic Activity Report, 24 February-2 March 2021
Managing Editor: Sally Sennert.
Please cite this report as:
Global Volcanism Program, 2021. Report on Kirishimayama (Japan) (Sennert, S, ed.). Weekly Volcanic Activity Report, 24 February-2 March 2021. Smithsonian Institution and US Geological Survey.
Kirishimayama
Japan
31.934°N, 130.862°E; summit elev. 1700 m
All times are local (unless otherwise noted)
JMA lowered the Alert Level for Kirishimayama to 1 (on a scale of 1-5) on 1 March. The number of volcanic earthquakes had increased in late December 2020 but then began to decline in January 2021 and continued the downward trend through February. No other observation data showed signs of unrest.
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.
