Mayon Volcano shows increased seismic activity; Alert Level 3 remains

Mayon Volcano in Albay has been having continuous tremor-like weak volcanic earthquakes since Monday afternoon that steadied and increased in strength on Tuesday, the Philippine Institute of Volcanology and Seismology (PHIVOLCS) said in an advisory.

The said quakes, recorded since 3:47 p.m. on Monday, are persisting up to Tuesday afternoon.

"These events last approximately 11 seconds and recur at intervals of 5 seconds," PHIVOLCS said.

"This resulted in an abrupt and sustained increase in the level of seismic energy release beginning 03 July 2023," it added.

A satellite has detected a pronounced increase in sulfur dioxide emission on Monday. Meanwhile, "a same-day sharp increase in average SO2 emission to 1,558 tonnes/day measured by campaign survey" was also observed.

PHIVOLCS said the activities may have been caused by magmatic gas within the edifice causing dome-collapse pyroclastic density currents (PDCs) and continuous rockfalls.

Two-minute dome-collapse PDCs were also observed within 1-2 kilometers from the crater at the Basud Gully (eastern slopes), Mi-isi Gully (southern slope), and Bonga Gully (southeastern slope).

Ashfall traces have also been reported by residents of Guinobatan and Ligao in Albay.

Alert Level 3 remains in effect in Mayon Volcano, PHIVOLCS said. This means increased tendency towards a hazardous eruption.

The increase in seismic energy release is being monitored closely, PHIVOLCS added.

Meanwhile, the agency strongly recommends that the areas within the 6-kilometer radius Permanent Danger Zone remain evacuated, and preparation for evacuations for communities within the 7-kilometer and 8-kilometer Danger Zones be done.

PHIVOLCS raised the alert level on Mayon Volcano from level 2 to level 3 on June 8 signifying "increased tendency towards a hazardous eruption." —Jiselle Anne Casucian/KG, GMA Integrated News