Geologic Background:
One of Japan's most noted volcanoes, Bandai-san
rises above the north shore of Lake Inawashiro. The
Bandai complex is formed of several overlapping
stratovolcanoes, the largest of which is O-Bandai.
O-Bandai volcano was constructed within a
horseshoe-shaped caldera that formed about 40,000 years
when an earlier volcano collapsed, forming the Okinajima
debris avalanche, which traveled to the SW and was
accompanied by a plinian explosive eruption. Four major
phreatic eruptions have occurred during the past 5000
years, two of them in historical time, in 806 and 1888.
Seen from the south, Bandai presents a conical profile,
but much of the north side of the volcano is missing as a
result of the collapse of Ko-Bandai volcano during the
1888 eruption, in which a debris avalanche buried several
villages and formed several large lakes.
Historic Activity:
- A phreatic eruption in 1888 was associated with a
collapse of the edifice, producing a huge debris
avalanche that buried villages at the foot of the volcano
and killed 461 people.
Recent Activity:
- Increased seismicity toward the end of November
1988.
- Unprecedented increase in seismicity during Aug
14-16, 2000.
Data Sources:
- Smithsonian's SEAN Bulletin (V. 12, No. 6 and V. 13,
No. 11).
- Global Volcanism Network (V. 25, No. 8).
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