Report on Tokachidake (Japan) — July 1995
Bulletin of the Global Volcanism Network, vol. 20, no. 7 (July 1995)
Managing Editor: Richard Wunderman.
Tokachidake (Japan) For the first time since 1989, monthly seismic events total over 100
Please cite this report as:
Global Volcanism Program, 1995. Report on Tokachidake (Japan) (Wunderman, R., ed.). Bulletin of the Global Volcanism Network, 20:7. Smithsonian Institution. https://doi.org/10.5479/si.GVP.BGVN199507-285050.
43.418°N, 142.686°E; summit elev. 2077 m
All times are local (unless otherwise noted)
Increased seismicity starting on 9 July was recorded 4.3 km NNW of the 1962 crater. The peak daily high for the month took place on 17 July (28 events). During the entire month of July there were 101 events. Not since January 1989, when 179 seismic events were recorded, have >100 events occurred in one month.
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.