|BULUSAN VOLCANO BULLETIN 11 September 2011 8:00 A.M.|
|Saturday, 10 September 2011 23:03|
Bulusan Volcano's (12.7667°N, 124.0500°E) seismic network did not detect any volcanic earthquake during the past 24 hours. Yesterday, steaming activity at the known thermal vents was not observed due to thick clouds covering the summit. However, early this morning weak to moderate emission of white steam at the southwest vent while no steaming at the southeast vent could be observed. Ground deformation survey (precise leveling) conducted last 16 - 20 August 2011 yielded no significant change at Inlagadian leveling line on the NNE flank but yielded slight inflation at Mapaso leveling line on the SSE flank, relative to the previous survey last 07-09 June 2011.
Bulusan Volcano's status remains at Alert Level 1, meaning that current volcanic activity is driven by shallow, hydrothermal processes. Entry into the 4-kilometer radius Permanent Danger Zone (PDZ) is strictly prohibited due to sudden steam and ash eruptions. Due to the prevailing wind direction, residents in the northwest and southwest sectors of the volcano are reminded to take precautions against ashfall from sudden eruptions. Civil aviation authorities must also warn pilots to avoid flying close to the volcano's summit as ejecta from sudden eruptions may be hazardous to aircraft. If possible, aircraft should avoid airspace west of the volcano as volcanic ash is likely to be dispersed in this direction by prevailing winds. Furthermore, people living within valleys and along 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 development will be relayed to all concerned.