LEGAZPI CITY, 22June2015 — Very slight traces of ashfall were reported in the villages of San Jose, Saclan, San Rafael and Dapdap in Bulusan town, Rachelle Miranda, Office of Civil Defense (OCD) Bicol spokesperson, said early Monday morning.
This, after Mount Bulusan in Sorsogon spewed a 150-meter-high ash steam column at around 1:15 p.m. Sunday, which drifted towards these four villages in the town of Bulusan.
The Philippine Institute of Volcanolgy and Seismology (Phivolcs) said that prior to the low-energy ash and steam ejection on Sunday afternoon, Phivolcs seismic instruments recorded three volcanic earthquakes and 41 quakes caused by movements of local faults surrounding the volcano during the past 24-hour observation period.
When asked about the implications of the 41 local fault quakes to the volcano’s restive condition, Ed Laguerta, Phivolcs resident volcanologist, said it needs further close monitoring because small earthquakes faults are found in the surrounding of the volcano.
He said the steam pressurization underneath the volcano edifice might have triggered the movements in the local earthquake faults, saying further that “it needs to be thoroughly evaluated.”
On Friday, Bulusan volcano blew its top, sending a 1.5-kilometer high ash plume cloud that drifted towards five villages in Juban town.
Laguerta said the eruption was a phreatic type similar to the four steam-driven explosions that happened last week.
Alert Level 1 remains in effect and he warned villagers not to venture in the four-km permanent danger zone due to sudden phreatic explosions.
Civil aviation authorities were likewise told to advise pilots to avoid flying close to the volcano’s summit as ash from any sudden phreatic eruption can be hazardous to aircraft. (PNA)