Geologic Background:
Tungurahua is a steep-sided stratovolcano that
towers 3 km above its northern base. It is one of
Ecuador's most active volcanoes and is located about 75
km south of Quito. Three major volcanic edifices have
been seuentially constructed since the mid-Pleistocene.
Historic Activity:
- Historical eruptions have originated from the summit
crater and have included strong explosions and sometimes
lava flows, lahars, and pyroclastic flows that reached
populated areas at the volcano's base. The volcano's
complex historical record includes sudden, violent
eruptions.
- The last major eruption took place from 1916 to 1918,
although minor activity continued until 1925.
Recent Activity:
- Increased seismicity began in mid-September 1999 and
an eruption started on October 5, 1999. Explosive block
and ash eruptions.
- During 2000, Tungurahua experienced continuous but
relatively mild activity with occational lava
fountaining.
- Activity continued through 2001.
Data Sources:
- Global Volcanism Network (V. 24, No. 9 to V. 26, No.
7).
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