Indonesian authorities are reporting that activity at Mount Sinabung volcano is still very high. Current eruptive phase started on January 4, when at least 5 pyroclastic flows traveled down on the southeastern side and reached lengths of up to 4 km. Associated ash plumes were reported rising to altitudes of 7.4 km.
Growing lava dome producing numerous explosions and pyroclastic flows prompted even more evacuations from villages around the volcano.
There are currently 20 491 refugees from 6 387 families (25 villages). 1 200 are seniors, 179 pregnant women and 606 infants (Badan Nacional Penanggulangan Bencana -BNPB).
Sutopo Purwo Nugroho, head of Data Information and Public Relation, said:
"Worst-case scenario contingency plans need to be finalized... People are encouraged to remain vigilant and to follow government directives. (BNPB (January 4, 2014)
He also noted that during the eruption of Mount Merapi in 2010, an increase in volcanic activity triggered determination of the evacuation radius of 5 km and then 10 km, 15 km and 20 km.
The following video shows some of the yesterday's flows through the VSI webcam:
Video courtesy Volcano Discovery
Latest entry to GVP's weekly volcanic report (December 25 - 31. 2013):
"PVMBG reported that seismicity at Sinabung increased during December 21 - 26 and indicated rising magma and lava-dome growth. Observers in Ndokum Siroga, about 8.5 km away, noted dense white plumes rising 70 - 1 200 m above the crater. Roaring was also periodically heard. A lava dome in the North Crater, visible on December 24, was 56 m high and 210 m wide. During December 25 - 26 plumes were white and gray, and rose 300 - 400 m above the crater. On December 26, the lava-dome volume was estimated to be over 1 million cubic meters, with a growth rate of 3.5 cubic meters per second. The Alert Level remained at 4 (on a scale of 1-4). Visitors and tourists were prohibited from approaching the crater within a radius of 5 km."
On December 30, BNPB reported: "Collapsing parts of the lava dome generated block-and-ash flows as well as pyroclastic flows which traveled as far as 3.5 km down the SE flank. Explosions and pyroclastic flows generated ash plumes that rose at least 6 km above the crater."
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: Mount Sinabung - January 4, 2014. Credit: Badan Geology via Volcano Discovery