Report on Karangetang (Indonesia) — 15 August-21 August 2007
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 15 August-21 August 2007
Managing Editor: Sally Kuhn Sennert
Please cite this report as:
Global Volcanism Program, 2007. Report on Karangetang (Indonesia). In: Sennert, S K (ed.), Weekly Volcanic Activity Report, 15 August-21 August 2007. Smithsonian Institution and US Geological Survey.
2.781°N, 125.407°E; summit elev. 1797 m
All times are local (unless otherwise noted)
The Alert Status of Karangetang was raised on 18 August from 3 to 4 (on a scale of 1-4) due to increased eruptive activity, based on visual observation and increased seismicity. According to news articles, lava flowed about 1 km down the S slope and "booming" noises were heard. Thick ashfall covered villages, farms, and trees on the slopes.
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.