Report on Karangetang (Indonesia) — 8 December-14 December 2010
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 8 December-14 December 2010
Managing Editor: Sally Kuhn Sennert
Please cite this report as:
Global Volcanism Program, 2010. Report on Karangetang (Indonesia). In: Sennert, S K (ed.), Weekly Volcanic Activity Report, 8 December-14 December 2010. Smithsonian Institution and US Geological Survey.
2.781°N, 125.407°E; summit elev. 1797 m
All times are local (unless otherwise noted)
CVGHM reported that during November until 12 December observers at the station at Salili, S of the volcano, noted a drastic decrease in the occurrence of pyroclastic flows on Karangetang's flanks. Seismicity also decreased, and white plumes rose up to 300 m above the craters. The Alert Level was lowered to 2 (on a scale of 1-4).
Geologic Background. Karangetang (Api Siau) volcano lies at the northern end of the island of Siau, north of Sulawesi. The stratovolcano contains five summit craters along a N-S line. It is one of Indonesia's most active volcanoes, with more than 40 eruptions recorded since 1675 and many additional small eruptions that were not documented in the historical record (Catalog of Active Volcanoes of the World: Neumann van Padang, 1951). Twentieth-century eruptions have included frequent explosive activity sometimes accompanied by pyroclastic flows and lahars. Lava dome growth has occurred in the summit craters; collapse of lava flow fronts has also produced pyroclastic flows.