Report on Tokachidake (Japan) — December 1995
Bulletin of the Global Volcanism Network, vol. 20, no. 11 (December 1995)
Managing Editor: Richard Wunderman.
Tokachidake (Japan) Gradual increase in the number of seismic events
Please cite this report as:
Global Volcanism Program, 1995. Report on Tokachidake (Japan). In: Wunderman, R. (ed.), Bulletin of the Global Volcanism Network, 20:11. Smithsonian Institution. https://doi.org/10.5479/si.GVP.BGVN199512-285050.
43.418°N, 142.686°E; summit elev. 2077 m
All times are local (unless otherwise noted)
During the second half of December, the number of earthquakes gradually increased, totalling 103 for the month. Consisting of a NE-SW aligned group of stratovolcanoes, Tokachi has a record that includes a partial cone collapse in 1925 that led to ~144 deaths and 5,000 homes destroyed.
Geologic Background. Tokachidake volcano consists of a group of dominantly andesitic stratovolcanoes and lava domes arranged on a NE-SW line above a plateau of welded Pleistocene tuffs in central Hokkaido. Numerous explosion craters and cinder cones are located on the upper flanks of the small stratovolcanoes, with the youngest Holocene centers located at the NW end of the chain. Frequent historical eruptions, consisting mostly of mild-to-moderate phreatic explosions, have been recorded since the mid-19th century. Two larger eruptions occurred in 1926 and 1962. Partial cone collapse of the western flank during the 1926 eruption produced a disastrous debris avalanche and mudflow.
Information Contacts: Volcanological Division, Seismological and Volcanological Department, Japan Meteorological Agency (JMA), 1-3-4 Ote-machi, Chiyoda-ku, Tokyo 100 Japan.