Bulusan volcano (Philippines): new phreatic explosion, ash plume of 2000 m
Fri, 10 Jun 2016, 07:4607:46 AM | BY: T
A sudden eruption occurred this morning (at 11:35 local time). An explosion generated an ash plume that rose about 2000 m above the volcano's summit and drifted northwest, causing light ash falls in nearby downwind areas.
Eruption of Bulusan volcano this morning (PHILVOLCS)
According to PHILVOLCS, the eruption preceded by a seismic swarm with more than 100 small earthquakes and lasted 5 minutes. The eruption itself was only steam-driven - no magma itself has reached the surface,- and caused by explosion of over-pressurized and over-heated fluids from the volcano's strongly developed hydrothermal system.
A similar explosion had occurred on 21 February. Following it, scientists monitoring the volcano have been seeing an inflation of the edifice (swelling of the ground) since May, probably caused by magma intruding at depth. This would have been providing new energy (heat) to the system and cause increasing instability.
Bulusan's official status remains unchanged at "Alert Level 1 (abnormal)" on the scale of 0 (normal) to 5 (highest):
"This indicates that hydrothermal processes are underway beneath the volcano that may lead to more steam-driven eruptions. The local government units and the public are reminded that entry to the 4-kilometer radius Permanent Danger Zone (PDZ) is strictly prohibited due to the possibility of sudden and hazardous steam-driven or phreatic eruptions." (PHILVOLCS)
Wed, 8 Jun 2016, 06:00
Bulusan volcano (Luzon, Philippines) - Smithsonian / USGS Weekly Volcanic Activity Report for 8 June-14 June 2016 (New Activity / Unrest)
PHIVOLCS reported that a five-minute-long phreatic explosion at Bulusan began at 1135 on 10 June, and generated an ash plume that rose 2 km and drifted NW. The Alert Level remained at 1, indicating abnormal conditions and a 4-km radius Permanent Danger Zone (PDZ). ... Read all
Mon, 22 Feb 2016, 12:05
An unexpected small eruption occurred at the volcano yesterday afternoon. At 17:01 local time, two successive small explosions from a fissure vent on the west-northwestern part of the summit crater produced an ash plume that rose approx. 500 meters and caused light ash fall in some nearby villages such as Juban 11 km NW and Irosin 8 km SSW of the volcano. ... Read all