Report on Sinabung (Indonesia) — 1 February-7 February 2017
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 1 February-7 February 2017
Managing Editor: Sally Kuhn Sennert
Please cite this report as:
Global Volcanism Program, 2017. Report on Sinabung (Indonesia). In: Sennert, S K (ed.), Weekly Volcanic Activity Report, 1 February-7 February 2017. Smithsonian Institution and US Geological Survey.
3.17°N, 98.392°E; summit elev. 2460 m
All times are local (unless otherwise noted)
Based on PVMBG observations, satellite and webcam images, and wind data, the Darwin VAAC reported that during 2-7 February ash plumes from Sinabung rose to altitudes as high as 7.3 km (24,000 ft) a.s.l. and drifted NE, E, SE, and SW.
BNPB reported that each day during 2-7 February there were 8-12 ash-producing events with plumes rising as high as 2 km above the crater and drifting E. Pyroclastic flows traveled as far as 2 km S, SE, and E. BNPB noted that more areas had been designated disaster prone, therefore the number of people needed to be relocated also increased. The Alert Level remained at 4 (on a scale of 1-4), with an exclusion zone of 7 km from the volcano on the SSE sector, and 6 km in the ESE sector, and 4 km in the NNE sector.
Geologic Background. Gunung Sinabung is a Pleistocene-to-Holocene stratovolcano with many lava flows on its flanks. The migration of summit vents along a N-S line gives the summit crater complex an elongated form. The youngest crater of this conical andesitic-to-dacitic edifice is at the southern end of the four overlapping summit craters. The youngest deposit is a SE-flank pyroclastic flow 14C dated by Hendrasto et al. (2012) at 740-880 CE. An unconfirmed eruption was noted in 1881, and solfataric activity was seen at the summit and upper flanks in 1912. No confirmed historical eruptions were recorded prior to explosive eruptions during August-September 2010 that produced ash plumes to 5 km above the summit.