Report on Sangeang Api (Indonesia) — 26 December-1 January 2013
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 26 December-1 January 2013
Managing Editor: Sally Kuhn Sennert
Please cite this report as:
Global Volcanism Program, 2012. Report on Sangeang Api (Indonesia). In: Sennert, S K (ed.), Weekly Volcanic Activity Report, 26 December-1 January 2013. Smithsonian Institution and US Geological Survey.
8.2°S, 119.07°E; summit elev. 1912 m
All times are local (unless otherwise noted)
CVGHM reported that during November through mid-December observers at the Sangeang, Bima observation post (50 km SW) noted occasional diffuse white plumes rising 5-15 m above Sangeang Api's crater. The lava dome and surrounding areas had not changed compared to October observations. Avalanches had occurred on the W and SW flanks. Earthquakes had declined. The Alert Level was lowered to 2 (on a scale of 1-4) on 21 December.
Geologic Background. Sangeang Api volcano, one of the most active in the Lesser Sunda Islands, forms a small 13-km-wide island off the NE coast of Sumbawa Island. Two large trachybasaltic-to-tranchyandesitic volcanic cones, Doro Api and Doro Mantoi, were constructed in the center and on the eastern rim, respectively, of an older, largely obscured caldera. Flank vents occur on the south side of Doro Mantoi and near the northern coast. Intermittent historical eruptions have been recorded since 1512, most of them during in the 20th century.