Report on Karangetang (Indonesia) — 9 March-15 March 2016
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 9 March-15 March 2016
Managing Editor: Sally Kuhn Sennert
Please cite this report as:
Global Volcanism Program, 2016. Report on Karangetang (Indonesia). In: Sennert, S K (ed.), Weekly Volcanic Activity Report, 9 March-15 March 2016. Smithsonian Institution and US Geological Survey.
2.781°N, 125.407°E; summit elev. 1797 m
All times are local (unless otherwise noted)
Based on observations conducted at the Karangetang Volcano Observation Post in the village of Salili, PVMBG reported that during 1 February-[15 March] the lava dome was incandescent at night. Variable amounts of white and blue emissions rose as high as 150 m above Main Crater. Seismicity was dominated by shallow volcanic earthquakes; volcanic and multi-phase earthquakes declined though signals indicated that lava-dome growth continued. Thermal anomalies had not been detected in satellite images since 8 March. The Alert Level was lowered to 2 (on a scale of 1-4); visitors and residents were warned not to approach Karangetang within a 1.5-km radius.
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.