Alert level 1 raised over Bulusan Volcano 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 following increased seismic activities.

“We detected abnormal quakes and increase of hot spring temperature,” Paul Alanis, senior science research specialist of Phivolcs based in Ligñon Hill Observatory in Legazpi City said.

In a bulletin issued at 11:10 a.m. on Sunday, Phivolcs said that from May 4 to May 5, there was an increase in seismic activity which was deemed “abnormal.”

Sixteen volcanic earthquakes were recorded.  There was a notable increase in water temperature of the monitored hot springs. Weak emission of white steam plumes was observed from the southeast vents of the volcano.

“This indicates that hydrothermal processes may be underway beneath the volcano that may lead to steam-driven eruptions,” the bulletin added.

The tilt data from April 29 to May 5 indicated slight inflation of the upper slopes.

Alanis reminded local government units and the public not to enter the 4-kilometer radius Permanent Danger Zone of the volcano for possible sudden and hazardous phreatic eruptions, rockfall, and landslide.

Bulusan’s last phreatic eruption was recorded on June 5, 2017. The alert level was lowered to zero or normal condition on August 15, 2018.