(Eagle News) — Bulusan is now on alert level 1, which means it is in an “abnormal condition.”
The Philippine Institute of Volcanology and Seismology on Monday, July 6, said the volcano’s alert level was raised from 0 after 53 volcanic earthquakes were recorded since July 3, and a “short-term inflation of the edifice” was recorded since late February.
PHIVOLCS said the quakes included 43 low-frequency events that are “associated with weak and shallow hydrothermal or magmatic gas activity within the edifice.”
“The increased seismicity could be succeeded by steam-driven or phreatic eruptions at the summit crater or from flank vents on the upper to middle slopes, despite the absence of visible degassing or steaming from the active vent this year,” PHIVOLCS said.
As for the “short-term inflation,” PHIVOLCS said this indicates that “volcanic processes are underway beneath the edifice that may be caused by deep-seated degassing or hydrothermal activity or magmatic intrusion.”
With the raising to alert level 1, PHIVOLCS reiterated its reminder that entry into the 4-kilometer radius Permanent Danger Zone “is strictly prohibited and that vigilance in the Extended Danger Zone (EDZ) must be exercised due to the increased possibilities of sudden and hazardous phreatic eruptions.”
Pilots were also advised against flying close to the volcano’s summit “as ash from any sudden phreatic eruption can be hazardous to aircraft.”
“Furthermore, people living within valleys and along river/stream channels especially on the southeast, southwest and northwest sector of the edifice should be vigilant against sediment-laden stream flows and lahars in the event of heavy and prolonged rainfall,” PHIVOLCS said.
It said it was “closely monitoring Bulusan Volcano’s condition and any new development will be communicated to all concerned stakeholders.”
Earlier, PHIVOLCS said it was keeping a “close watch” on Kanlaon after a series of earthquakes struck the volcano in Negros.