Mayon back to Alert Level 1

MANILA, Philippines — Mayon Volcano in Albay has been showing signs of activity, prompting state seismologists to place it under Alert Level 1 anew.

In a bulletin issued yesterday afternoon, the Philippine Institute of Volcanology and Seismology (Phivolcs) cited various observations that indicated the volcano is under abnormal condition.

Mayon’s status was lowered from Alert Level 1 to zero on July 30 this year.

Recent developments showed the need to again raise the alert level, Phivolcs said.

Daily visual and camera monitoring of the summit crater showed the remnant lava dome emplaced toward the end of the 2018 eruption had changed between June 6 and Aug. 20.

“Ground deformation observations from global positioning system, precise leveling, and electronic tilt and distance meter monitoring showed a slight short-term inflation of the volcano’s edifice, particularly on the northwestern and southeastern slopes since April,” Phivolcs said.

Sulfur dioxide emission on Aug. 12 averaged 688 tons per day or near baseline level, it added

“Short-lived spikes in the number of low-frequency volcanic earthquakes were recorded between May 26 and June 20. But for most of the year, only baseline seismic activity has been detected,” state seismologists said.

These parameters indicated that volcanic gas-induced pressurization at the shallow depths of the edifice might be occurring, causing the summit dome of Mayon to be pushed out.

Entry into the volcano’s permanent danger zone is prohibited due to possible sudden steam-driven or phreatic eruptions as well as rockfalls.

People living in valleys and river channels were advised to stay alert as sediment-laden streamflows and lahars can occur, especially during prolonged and heavy rain.