Report on Karangetang (Indonesia) — 29 November-5 December 2000
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 29 November-5 December 2000
Managing Editor: Gari Mayberry
Please cite this report as:
Global Volcanism Program, 2000. Report on Karangetang (Indonesia). In: Mayberry, G (ed.), Weekly Volcanic Activity Report, 29 November-5 December 2000. Smithsonian Institution and US Geological Survey.
2.781°N, 125.407°E; summit elev. 1797 m
All times are local (unless otherwise noted)
The VSI reported that volcanic activity during 21-27 November was similar to the previous week. A thin ash plume was observed rising ~600 m above the summit from the main crater and Crater II. Booming sounds were frequently heard from the volcano's summit, and a "red flame" was observed some nights rising ~100 m above the summit. Seismic activity was high and dominated by discontinuous tremor. In total, 21 small explosions were recorded. The Alert Level remained at 2 (ranging from 1 to 4).
Geologic Background. Karangetang (Api Siau) volcano lies at the northern end of the island of Siau, about 125 km NNE of the NE-most point of Sulawesi island. 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 have produced pyroclastic flows.