Wednesday, 23 February 2011 14:28


21 February 2011

 10:00 AM

At 0912H today an explosion occurred at Bulusan Volcano (12°46.2’N, 124°03’E). This event was recorded as explosion type earthquake lasting for about nineteen (19) minutes and was accompanied by a rumbling sound which was heard up to ten (10) kilometers away in the town of Juban, Sorsogon. The explosion produced a greyish ash column that rose to a height of about three (3) kilometres above the summit before drifting to the southwest. Preliminary field investigation confirmed the presence of ash deposits in Barangay Monbon and Irosin proper in Irosin Sorsogon.

Bulusan Volcano's status remains at Alert Level 1.  This means that the source of activity is hydrothermal and shallow. Entry to the 4-kilometer radius Permanent Danger Zone (PDZ) is strictly prohibited, since the area is at risk to sudden steam and ash explosions.  Due to the prevailing wind direction, residents in the northwest and southwest sectors of the volcano are reminded to take precautions against ashfalls.  Civil aviation authorities must also warn pilots to avoid flying close to the volcano's summit as ejected ash and volcanic fragments from sudden explosions may be hazardous to aircraft.  Furthermore, people living near valleys and river/stream channels should be vigilant against sediment-laden stream flows and lahars in the event of heavy and prolonged rainfall.  DOST-PHIVOLCS is closely monitoring Bulusan Volcano's activity and any new significant development will be immediately relayed to all concerned.