Report on Lokon-Empung (Indonesia) — December 2003
Bulletin of the Global Volcanism Network, vol. 28, no. 12 (December 2003)
Managing Editor: Richard Wunderman.
Lokon-Empung (Indonesia) During November, elevated seismicity and a minor gas plume
Please cite this report as:
Global Volcanism Program, 2003. Report on Lokon-Empung (Indonesia). In: Wunderman, R. (ed.), Bulletin of the Global Volcanism Network, 28:12. Smithsonian Institution. https://doi.org/10.5479/si.GVP.BGVN200312-266100.
1.358°N, 124.792°E; summit elev. 1580 m
All times are local (unless otherwise noted)
Ongoing seismicity at Lokon was reported in BGVN 28:10. The Volcanological Survey of Indonesia (VSI) report for 27 October-30 November showed continuing seismicity (table 8), and a white gas plume rising 75-150 m from the Tompaluan crater. The volcano remained at alert level 2 (on a scale of 1-4).
|Date||Deep volcanic (A-type)||Shallow volcanic (B-type)||Tectonic|
|27 Oct-02 Nov 2003||3||29||22|
|03 Nov-09 Nov 2003||15||171||26|
|10 Nov-16 Nov 2003||9||146||43|
|17 Nov-23 Nov 2003||22||96||20|
|24 Nov-30 Nov 2003||7||116||21|
Geologic Background. The twin volcanoes Lokon and Empung, rising about 800 m above the plain of Tondano, are among the most active volcanoes of Sulawesi. Lokon, the higher of the two peaks (whose summits are only 2 km apart), has a flat, craterless top. The morphologically younger Empung volcano to the NE has a 400-m-wide, 150-m-deep crater that erupted last in the 18th century, but all subsequent eruptions have originated from Tompaluan, a 150 x 250 m wide double crater situated in the saddle between the two peaks. Historical eruptions have primarily produced small-to-moderate ash plumes that have occasionally damaged croplands and houses, but lava-dome growth and pyroclastic flows have also occurred. A ridge extending WNW from Lokon includes Tatawiran and Tetempangan peak, 3 km away.
Information Contacts: Dali Ahmad, Hetty Triastuty, Nia Haerani and Suswati, Vulcanological Survey of Indonesia (VSI), Jalan Diponegoro No. 57, Bandung 40122, Indonesia (URL: http://www.vsi.esdm.go.id/).