Residents in Sorsogon were still advised to be cautious, as Bulusan Volcano remains on Alert Level 1, or "low-level volcanic unrest."

In a Bagong Pilipinas Ngayon interview on Wednesday, Jan. 31, Philippine Institute of Volcanology and Seismology (Phivolcs) Director Dr. Teresito Bacolcol warned the public to refrain from entering the four-kilometer permanent danger zone (PDZ), as phreatic eruption is possible.

"We remind our people na nakatira sa Sorsogon malapit sa paanan ng Bulusan Volcano na Alert Level 1 prevails, which means it is currently at low-level unrest, which means pwedeng magkaroon ng stream-driven or phreatic eruptions (We remind our people residing in Sorsogon, those who are near the Bulusan Volcano, which is under Alert Level 1 that means it is currently at low-level unrest and stream-driven or phreatic eruption is possible)," Bacolcol said.

Based on the Phivolcs' data, eight volcanic earthquakes were recorded in Bulusan Volcano in the past 24 hours, which was lower than the record of 65 volcanic earthquakes on Jan. 30.

Bacolcol also said Phivolcs released an advisory on Jan. 28, as Bulusan Volcano showed increased seismic activity with 126 volcano-tectonic earthquakes.

Read: https://mb.com.ph/2024/1/28/seismic-activity-rises-in-bulusan-volcano-phivolc

Meanwhile, Bacolcol reminded the affected residents to evacuate when volcanic earthquakes with "strong" magnitudes have been felt.

"Kapag may malalakas na lindol na naramdaman nila, usually mga lindol sa bulkan mahihina lamang iyan pero kapag felt na, ibig sabihin tuloy-tuloy na iyong pag-angat ng magma and kapag nakaramdam na sila ng mga paglindol, then they have to move away from the danger zone" (When there are strong earthquakes felt, usually the earthquakes in volcanoes are weak, but if those are felt already, it means there is continuous rise of magma and when they felt tremors, then they have to move away from the danger zone)," he said.

Moreover, Bacolcol cited few signs that volcanoes are "quiet" which include less occurrences of volcanic earthquakes, minimal volcanic gasses emission, weak steaming, and less inflation of the volcano.

"Kapag ang ating monitored parameters are within the background levels, then we can say na tuloy-tuloy na ang pagkalma ng isang bulkan (When our monitored parameters are within the background levels, then we can say that there is continuous calming of a volcano)," he said.