20211026 mayon
State volcanologists urged the public to exercise caution and avoid going inside the Permanent Danger Zone's 6-km radius. File photo shows residents walking past a house half-buried by sand and rock from Mayon volcano. Image Credit: AFP

Manila: Pilots had been advised to fly a safe distance from the summit of the restive Mount Mayon in eastern Philippines as the alert level was raised due to the volcano's “increasing unrest.”

Any quick eruption's ash could endanger their aircraft, state volcanologists warned, as the alert status of Mt Mayon in Albay to Level 2 on Monday (June 5, 2023).


The Philippine Institute of Volcanology and Seismology (Philvolcs) said the raising of the alert level means "there is current unrest driven by shallow magmatic processes that could ultimately lead to phreatic eruptions or even precede hazardous magmatic eruption.”

High alert

Volcanologists cited visual camera and earthquake data, which point to an elevated risk of hazards from unexpected explosions, rockfall, and landslides.

Phivolcs urged the public to exercise caution and avoid going inside the Permanent Danger Zone's six-kilometer radius.

“In case of ash fall events that may affect communities downwind of Mayon’s crater, people should cover their nose with a damp, clean cloth or dust mask,” it said.

Phreatic eruptions are steam-driven explosions. In the meantime, magmatic eruptions cause the ejection of lava or tephra from a magma source deep inside the ground.

It’s been nearly three months after Phivolcs lowered Mayon's status to Alert Level 1.

Rockfall, earthquakes

Since April 1, there have been 318 rockfall incidents total, and 26 volcanic earthquakes have also been noted during that time.

According to Phivolcs, the lava dome's volume has expanded by almost 164,000 cubic meters since August 20, 2022, and by about 83,000 cubic meters since February 3.

The recent measurement, taken on May 23, averaged 162 tons per day, while the maximum sulfur dioxide emission, reported on April 29, reached 576 tons per day.

These low-level volcanic earthquakes, ground deformation, and volcanic gas characteristics are obscured, according to the institute, by recent sharp increases in rockfall occurrences that could potentially trigger more dome activity.