By Gabriela Baron
The Philippine Institute of Volcanology and Seismology (Phivolcs) on Sunday, Aug. 21, raised the alert level status over Mayon Volcano in Albay, citing “abnormal conditions” and “period of unrest.”
In its 4:00 p.m. bulletin, Phivolcs reported that daily visual and camera monitoring of the summit crater revealed that the remnant lava dome emplaced towards the end of the 2018 eruption “has undergone a change in morphology and slight extrusion.”
State volcanologists also observed slight short-term inflation of the volcano edifice, particularly on the northwestern and southeastern slopes.
Phivolcs reported average daily sulfur oxide emission levels of 688 tons near baseline levels on Aug. 12.
“These observation parameters indicate that volcanic gas-induced pressurization at the shallow depths of the edifice may be occurring, causing the summit dome of Mayon to be pushed out,” Phivolcs said.
The agency reminded the public that entry into the 6-kilometer Permanent Danger Zone must be strictly avoided due to an increase in the chances of sudden steam-driven or phreatic eruption and perennial hazards of rockfalls, avalanches, and ash bursts at the summit area.
“[People] living in valleys and active river channels are cautioned to remain vigilant against sediment-laden stream flows and lahars in the event prolonged and heavy rainfall brought about by the advent of the rainy season.”
–ag