Report on Sinabung (Indonesia) — 6 April-12 April 2016
Smithsonian / US Geological Survey Weekly Volcanic Activity Report, 6 April-12 April 2016
Managing Editor: Sally Kuhn Sennert
Please cite this report as:
Global Volcanism Program, 2016. Report on Sinabung (Indonesia). In: Sennert, S K (ed.), Weekly Volcanic Activity Report, 6 April-12 April 2016. 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 satellite images and information from PVMBG, the Darwin VAAC reported that during 6, 8-10, and 12 April ash plumes from Sinabung rose to altitudes of 3.3-4.8 km (11,000-16,000 ft) a.s.l. and drifted SW, W, and WNW.
On 10 April BNPB reported that the eruption at Sinabung has not shown any signs of ceasing since the onset of activity in September 2013. Activity remained high, characterized by almost daily lava extrusion and pyroclastic flows, and high levels of seismicity. Four events on 10 April generated ash plumes that rose as high as 2 km. BNPB noted that although there were no new evacuees that day, 9,322 people (2,592 families) remained in 10 evacuation centers. Many families awaited relocation; 1,212 people had already been permanently relocated to new homes. The Alert Level remained at 4 (on a scale of 1-4); the public was reminded to stay outside of a 3-km radius. People within 7 km of the volcano in the SSE sector, within 6 km in the ESE sector, and within 4 km in the NNE sector should remain evacuated.
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.