Report on Karangetang (Indonesia) — November 1985
Scientific Event Alert Network Bulletin, vol. 10, no. 11 (November 1985)
Managing Editor: Lindsay McClelland.
Karangetang (Indonesia) Small ash eruption
Please cite this report as:
Global Volcanism Program, 1985. Report on Karangetang (Indonesia) (McClelland, L., ed.). Scientific Event Alert Network Bulletin, 10:11. Smithsonian Institution.
2.781°N, 125.407°E; summit elev. 1797 m
All times are local (unless otherwise noted)
"Api Siau erupted from the main crater (Kawah Utama) on 6 November. A 1.5-km-high ash column covered villages S of the volcano (Salili, Beong, Kanawong, and Lehi) with 1-3 mm of ash. Detonations were heard from the observation post at Muaralawa, 4.5 km SW of the volcano. Additional detonations were reported throughout the month. Possible precursory signs of this activity included a darkening of the normally whitish quiescent plume beginning on 4 November."
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.
Information Contacts: T. Casadevall and L. Pardyanto, VSI.