Phivolcs raises alert level 1 over Mt. Bulusan in Sorsogon
LEGAZPI CITY — The Philippine Institute of Volcanology and Seismology (Phivolcs) raised the alert status of Bulusan Volcano in Sorsogon province to Alert Level 1 (low-level unrest) after the series of volcanic earthquakes recorded during the past few days.
In a bulletin issued at 3 p.m. on Wednesday, Oct. 25, Phivolcs said 121 volcanic earthquakes were recorded by the Bulusan Volcano Network since Oct. 14.
The 37 of these were volcano-tectonic earthquakes that “were associated with rock fracturing processes at depths of one to nine kilometers beneath the northwestern and southeastern slopes of the volcano edifice.”
Based on the ground deformation data, an inflation or swelling at the southern flank was noted since February and of the northeastern flank since September, while volcanic carbon dioxide concentrations from June to August was also detected.
Local government units and the public were reminded to avoid entry into the 4-kilometer radius permanent danger zone and be vigilant in the 2-kilometer extended danger zone in the southeast sector due to increased possibilities of sudden and hazardous phreatic eruptions from the summit crater and/or lateral vents.
On Jan. 18, the alert level over the volcano was lowered to zero.