|BULUSAN VOLCANO BULLETIN 07 April 2011 8:00 A.M.|
|Wednesday, 06 April 2011 23:12|
Bulusan Volcano’s (12°46.2’N, 124°03’E) seismic network did not detect any volcanic earthquake during the past 24 hours. During cloud break yesterday, wispy to weak emission of white steam was observed at the southeast and northwest thermal vents while the summit crater was cloud-covered during the past observation period. Measurements of sulphur dioxide (SO2) emission rate yesterday showed a decline to 28 tonnes per day (t/d) compared from the previous reading of 38 t/d (April 5, 2011). Results of ground deformation survey (precise leveling) conducted last 01-05 March 2011 showed no significant change as compared with 25-29 January 2011 survey. No other significant volcanic activity was observed since the 21 February 2011 ash explosion. No lahar event was reported or observed.
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. If possible aircraft should avoid flying on the western side of the volcano as volcanic debris are likely to be carried in this direction by the prevailing winds. 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.