Pyroclastic flows continue at Sinabung volcano, Indonesia

Lava extrusion continues at Indonesian Sinabung volcano. A series of small to moderately sized pyroclastic flows occurred this morning at the volcano. 

Whether the apparently more intense activity is a sign of increased lava effusion is difficult to say, VolcanoDiscovery reported.

The flows were likely produced as parts of the upper, unstable and still growing viscous lava dome on the SE flank collapsed:

Video courtesy of VolcanoDiscovery / PVMBG webcam

According to news articles a pyroclastic flow at Sinabung traveled 2 km SE down the flanks at on September 24. The height of a corresponding ash plume could not be determined because it rose into the cloud cover. About 4 700 people remained in evacuation shelters.

On September 30 at 17:20 local time (10:20 UTC) an ash plume rose 2 km and a pyroclastic flow traveled 3.5 km.

Geologic 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, 2460-m-high andesitic-to-dacitic volcano is at the southern end of the four overlapping summit craters.

An unconfirmed eruption was noted in 1881, and solfataric activity was seen at the summit and upper flanks of Sinabung 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. (GVP)

Featured image credit: Pusat Vulkanologi dan Mitigasi Bencana Geologi (PVMBG)