The Philippine Institute of Volcanology and Seismology (Phivolcs) on Monday morning raised Albay’s Mayon Volcano to Alert Level 2 due to “increasing unrest”.

In a 10 am bulletin, it said: “Since the last week of April 2023, daily visual and camera monitoring of the summit crater revealed an increase in rockfall from the Mayon Volcano’s summit lava dome indicating a seismic growth.”

Phivolcs reported that rockfall increased in frequency from five events per day to 49 events per day from 5:00 on June 4 to 5 am on June 5.

“These low-level volcanic earthquakes, ground deformation, and volcanic gas parameters are overshadowed by recent steep increases in rockfall events which may possibly lead to further dome activity,” it said.

“In view thereof, the Phivolcs-DOST is raising the alert level of Mayon Volcano from Alert Level 1 (abnormal) to Alert Level 2 (increasing unrest),” it added.

According to Phivolcs, the unrest is caused by shallow magmatic processes which could result in phreatic eruptions or precede hazardous magmatic eruptions.

The public is advised to stay away from the six-kilometer Permanent Danger Zone to “minimize risk from sudden explosions, rockfall, and landslides”.

Phivolcs also advised to cover the mouth with a clean cloth or dusk mask.

Civil aviation authorities are directed to warn pilots against flying near the volcano’s summit since ash or sudden eruptions could be dangerous to their aircraft. Jaspearl Tan/DMS