Geologic Background:
Raung, one of Java's most active volcanoes, is a
massive stratovolcano in easternmost Java that was
constructed SW of the rim of Ijen caldera. The
unvegetated summit of Gunung Raung is truncated by a
dramatic steep-walled, 2-km-wide caldera that has been
the site of frequent historical eruptions. A prehistoric
collapse of Gunung Gadung on the west flank produced a
large debris avalanche that traveled 79 km from the
volcano, reaching nearly to the Indian Ocean. Raung
contains several centers constructed along a NE-SW line,
with Gunung Suket and Gunung Gadung stratovolcanoes being
located to the NE and west, respectively.
Historic Activity:
- Raung's first historic eruption in 1586 caused
fatalities, as did 5 more through 1817.
- Since then, eruptions have been reported more
frequently (52) but were only moderately explosive.
- Its last strong eruption, in July 1982, ejected a
6000 m plume.
Recent Activity:
- Strombolian activity in bottom of crater was observed
from air in July and August 1988.
- Continued plumes and seismicity in July 1990.
- Dense plumes were observed in early September and
October 1991.
- Ash clouds were reported in april and June 1997.
- Large ash plume on July 9, 2000.
Data Sources:
- Smithsonian's SEAN Bulletin (V. 7, No. 7 to V. 14,
No. 7)
- Global Volcanism Network (V. 15, No. 7 to V. 25, No.
10).
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