
The Philippine Institute of Volcanology and Seismology (Phivolcs) on Wednesday, Oct. 25 raised the alert status of Bulusan Volcano from Level 0 (normal) to Level 1 (low-level unrest).
In raising the alert level, Phivolcs noted that “Bulusan Volcano entered a period of low-level unrest with a sustained series of volcanic earthquakes that began on Oct. 14.”
The Bulusan Volcano Network (BVN) had recorded 121 volcanic earthquakes, 37 of which were volcano-tectonic earthquakes.
Phivolcs said the 37 earthquakes were caused by "rock fracturing processes" one to nine kilometers beneath the volcano’s northwestern and southeastern slopes.
The public and local government units are asked to avoid entering the four-kilometer permanent danger zone and the two-kilometer extended danger zone in the volcano's southeast sector.
Phivolcs warned of the possibility of sudden and dangerous phreatic eruptions from the summit crater or lateral vents.
It also warned of sediment-laden stream flows and lahars in the event of heavy and prolonged rainfall, if a phreatic eruption occurs. (Lizst Torres Abello)