PVMBG and BNPB reported that an eruption at Sinabung at 0641 on 7 May generated a dense ash plume that rose 2 km above the crater rim and drifted SW [correction: the plume drifted SE], causing the sky to turn dark in some areas. The eruption lasted 42 minutes and 49 seconds according to the seismic data. Ashfall was reported on farms in many villages in the Simpang Empat (7 km SE), Namanteran, Kabanjahe, and Berastadi districts. The Alert Level remained at 4 (on a scale of 1-4), with a general exclusion zone of 3 km and extensions to 7 km on the SSE sector, 6 km in the ESE sector, and 4 km in the NNE sector.

Geological Summary. 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.

Sources: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG, also known as CVGHM), Badan Nacional Penanggulangan Bencana (BNPB), Darwin Volcanic Ash Advisory Centre (VAAC), The Jakarta Post