Report on Kelut (Indonesia) — December 2000
Bulletin of the Global Volcanism Network, vol. 25, no. 12 (December 2000)
Managing Editor: Richard Wunderman.
Kelut (Indonesia) Inflation and increase in crater lake's temperature and surface height
Please cite this report as:
Global Volcanism Program, 2000. Report on Kelut (Indonesia) (Wunderman, R., ed.). Bulletin of the Global Volcanism Network, 25:12. Smithsonian Institution.
7.93°S, 112.308°E; summit elev. 1731 m
All times are local (unless otherwise noted)
Increasing crater lake temperature, water level, and inflation have been observed since 19 January 2001. Water temperature in the crater lake rose to 47.5-49.1°C. On 21 January water level rose 5 cm. Leveling measurement showed 5.5-6 mm of inflation. During 16-22 January, seismographs recorded 20 tectonic earthquake events. These observations prompted the VSI to increase Kelut's hazard status from 1 to 2 (on a scale of 1-4).
Geologic Background. The relatively inconspicuous Kelut stratovolcano contains a summit crater lake that has been the source of some of Indonesia's most deadly eruptions. A cluster of summit lava domes cut by numerous craters has given the summit a very irregular profile. Satellitic cones and lava domes are also located low on the E, W, and SSW flanks. Eruptive activity has in general migrated in a clockwise direction around the summit vent complex. More than 30 eruptions have been recorded from Gunung Kelut since 1000 CE. The ejection of water from the crater lake during the typically short but violent eruptions has created pyroclastic flows and lahars that have caused widespread fatalities and destruction. After more than 5000 people were killed during an eruption in 1919, an ambitious engineering project sought to drain the crater lake. This initial effort lowered the lake by more than 50 m, but the 1951 eruption deepened the crater by 70 m, leaving 50 million cubic meters of water after repair of the damaged drainage tunnels. After more than 200 deaths in the 1966 eruption, a new deeper tunnel was constructed, and the lake's volume before the 1990 eruption was only about 1 million cubic meters.
Information Contacts: Dali Ahmad, Volcanological Survey of Indonesia (VSI), Jalan Diponegoro No. 57, Bandung 40122, Indonesia (URL: http://www.vsi.esdm.go.id/).