Phivolcs removes alerts on Mt. Bulusan in Sorsogon

LEGAZPI CITY –– The Philippine Institute of Volcanology and Seismology (Phivolcs) on Saturday morning lowered the warning on Bulusan Volcano in Sorsogon from Alert Level 1 (abnormal) to Alert Level 0 (normal), following a general decline in monitoring parameters.

“This means observational parameters have returned to baseline or background levels and no magmatic eruption is foreseen in the immediate future,” a Phivolcs bulletin released at 8 a.m. said.

The monitoring shows that the frequency of volcanic earthquakes has declined to baseline levels (0-2 earthquakes/day) since May 17, 2019, which indicates that rock fracturing within the volcanic system associated with hydrothermal activity has diminished, the bulletin
said.

The overall ground deformation data indicate that there is no pressurization from subsurface magma, while the gas emission has dropped below detection levels.

However, Phivolcs reminds the public that entry to the four-kilometer radius permanent danger zone, particularly near the vents on the south-southeastern slopes is strictly prohibited due to the possibility of a sudden and hazardous steam-driven or phreatic eruption, rockfall, and landslide.

Pilots are also advised to avoid flying close to the volcano’s summit as ash from any sudden phreatic eruption could be hazardous to aircraft.

People living within valleys and along river or stream channels are also warned of possible lahar flow during times of heavy rainfall./lzb