Bulusan Volcano in Sorsogon continued to show “increased seismicity” in the past 24 hours, based on the latest monitoring of the Philippine Institute of Volcanology and Seismology (Phivolcs).
In its 8 a.m. bulletin issued on Saturday, June 11, Phivolcs said 178 “weak” and “shallow” earthquakes were recorded at Bulusan Volcano in the past 24 hours.
It has also detected a 150-meter-high “moderate” emission from the volcano.
Moreover, Bulusan Volcano’s sulfur dioxide or SO2 emission averaged 613 tons per day on June 10.
Phivolcs said the active volcano remains under Alert Level 1, which means there is a “slight increase” in volcanic earthquake and steam or gas activity.
Bulusan Volcano’s status has been raised from Level 0 to Level 1, following a phreatic eruption on June 5, which produced an ash plume more than a kilometer-high and left parts of Sorsogon blanketed in ash.
“Local government units and the public are reminded that entry into the four-kilometer radius permanent danger zone must be strictly prohibited and that vigilance in the two-kilometer extended danger zone on the southeast sector must be exercised due to the increased possibilities of sudden and hazardous phreatic eruptions,” Phivolcs said.
Likewise, Phivolcs asked civil aviation authorities to advise pilots to avoid flying close to the volcano’s summit as ash from any sudden phreatic eruption can be hazardous to aircraft.
“People living within valleys and along river/stream channels especially on the southeast, southwest and northwest sector of the edifice should be vigilant against sediment-laden stream flows and lahars in the event of heavy and prolonged rainfall should phreatic eruption occur,” it also said.