Bulusan volcano news:
Bulusan volcano (Philippines): small phreatic explosion
Monday Feb 22, 2016 12:05 PM | BY: T
Eruption of Bulusan volcano yesterday (youtube)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.
The eruption was likely phreatic or hydrothermal, i.e. the result of phreatic activity (overheated, pressurized water in the upper conduit area flashing to steam with no fresh magma involved, but this can only be determined if an analysis of the ash is done.
The eruption came with little warning, although PHILVOLCS mentions that increased seismicity was recorded on 20-21 February (something that in itself is not very unusual or sufficient to predict eruptions). The explosion itself was immediately preceded by a rock fracturing earthquake, which reflected the moment rock layers inside the volcano ruptured to release accumulated pressure.
Similar eruptions were observed last year in May-June. An exclusion zone of 4 km radius around the summit is in place and the alert level remains at 1 (on a scale from 0 to 5).
Links / Sources:
Links / Sources:
- BULUSAN VOLCANO ADVISORY 22 February, 2016 18:00 P.M. (PHILVOLCS)
- Bulusan Volcano Phreatic Explosion 2016 (Youtube)
Monday, Jul 20, 2015
PHIVOLCS reported that at 1310 on 17 July an explosion at Bulusan, detected by the seismic network for 11 minutes, generated an ash plume that rose 200 m above the crater and drifted WNW. ... [more]
Saturday, Jun 20, 2015
Another eruption, moderately strong, occurred 14:55 last Friday, producing an ash column that rose 1.5 km. The eruption was not directly visible, only parts of the ash plume could be spotted, but could be heard as rumbing in Monbon village. ... [more]
Tuesday, Jun 16, 2015
Two small steam-driven (i.e. phreatic) explosions occurred at the volcano this morning at 11:02 and 11:20 local time, PHILVOLCS reported. ... [more]
Saturday, May 23, 2015
During 13-15 and 17-19 May PHIVOLCS reported that six or fewer volcanic earthquakes were recorded at Bulusan. Weak steam emissions were occasionally observed rising from the SW vent and from a vent on the upper NW flank; plumes drifted SW, WNW, or drifted downslope. ... [more]
Thursday, May 07, 2015
New, sporadic explosions have occurred at the volcano since 1 May, ejecting small plumes of ash. PHILVOLCS raised the alert level to 1 and an exclusion zone of 4 km around the volcano is in place. ... [more]