The Philippine Institute of Volcanology and Seismology (Phivolcs) on Sunday, Jan. 28, said increased volcano-tectonic earthquakes were observed in Bulusan Volcano by the Bulusan Volcano Network.

Phivolcs said a total of 126 "weak" volcanic earthquakes ranging from magnitude 0.3 to magnitude 2.2 were generated between one to nine kilometers "beneath the north to northwestern flank of the volcano edifice."
There was "very weak to moderate" degassing of plumes from the summit crater and active vents drifting southwest to northwest, said Phivolcs.
It also advised the public to refrain from entering into the 4-kilometer radius Permanent Danger Zone (PDZ) and the 2-kilometer Extended Danger Zone (EDZ), as Alert Level 1 still prevails over Bulusan Volcano.
"Sustained seismic unrest for the past month indicates persistent hydrothermal activity that is likely driven by deep-seated magmatic processes and may lead to steam-driven or phreatic eruption," Phivolcs said.