Report on Karangetang (Indonesia) — 5 February-11 February 2003
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 5 February-11 February 2003
Managing Editor: Gari Mayberry
Please cite this report as:
Global Volcanism Program, 2003. Report on Karangetang (Indonesia). In: Mayberry, G (ed.), Weekly Volcanic Activity Report, 5 February-11 February 2003. Smithsonian Institution and US Geological Survey.
2.781°N, 125.407°E; summit elev. 1797 m
All times are local (unless otherwise noted)
Volcanic activity at Karangetang during 3-9 February consisted of low-level ash clouds rising above South and North craters, incandescent glow extending to 50 m above South Crater, and booming noises that were heard at the observation post. On 6 February at 0027 an ash explosion produced a cloud to an unknown height that deposited ash in villages SW of the volcano, including Akesembeka, Tarurane, Tatahadeng, Bebali, and Salili. During the report week, there was a significant increase in volcanic and emission earthquakes in comparison to the previous week. Karangetang remained at Alert Level 3 (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.