Phivolcs: Bulusan 'quiet' a day after explosion

A day after exploding and spewing a column of ash three kilometers into the air last Monday, Bulusan Volcano in Sorsogon was relatively quiet on Tuesday, with only one volcanic quake recorded in the last 24 hours. But the Philippine Institute of Volcanology and Seismology (Phivolcs) said the volcano remains at Alert Level 1, as an explosion may still occur. "For the past 24 hours, seismic observation at Bulusan Volcano revealed the occurrence of one volcanic earthquake. Steaming activity from the crater and known thermal vents was not observed due to thick clouds that covered the upper slope of the volcano during the past observation period. No other significant volcanic activity was observed since the 21 February 2011 ash explosion," Phivolcs said in its Wednesday update. On Monday, Bulusan exploded and spewed ash, which fell on many areas in Sorsogon and even in Masbate province. Several families in the affected areas were evacuated due to the ash fall. Phivolcs maintained Bulusan Volcano’s status at Alert Level 1, meaning the 4-km Permanent Danger Zone (PDZ) remains strictly off limits to people, "since the area is at risk of sudden steam and ash explosions." It also reminded residents in the northwest and southwest sectors of the volcano to take precautions against ash falls. "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," it said. It said people living near valleys and river or stream channels should be vigilant against sediment-laden stream flows and lahar in the event of heavy and prolonged rainfall. — LBG, GMA News