The Philippine Institute of Volcanology and Seismology (Phivolcs) is closely monitoring three active volcanoes due to increased volcanic activities.
On Thursday, Phivolcs raised the alert level (AL) for Mayon, situated in the Province of Albay, from AL 2, or increasing unrest to AL 3, or increased tendency towards a hazardous eruption.
In its Volcano Bulletin for Mayon issued at 12 noon on Thursday, Phivolcs noted that since the AL status was raised from AL 1 to Alert L 2 on June 5, 2023, the repeated collapse of the growing summit dome of Mayon Volcano has generated an increasing number and volume of rockfall events.
“A total of 267 rockfall events and two volcanic earthquakes were recorded from 05 to 08 June, compared to 54 rockfall events from 01 to 04 June 2023,” Phivolcs said.
In raising the alert level for Mayon, Phivolcs said Mayon is exhibiting magmatic eruption of a summit lava dome, with increased chances of lava flows and hazardous pyroclastic density current (PDC) affecting the upper to middle slopes of the volcano and of potential explosive activity within weeks or even days.
“It is therefore recommended that the 6-kilometer radius Permanent Danger Zone [PDZ] be evacuated due to the danger of PDCs, lava flows, rockfalls, and other volcanic hazards,” Phivolcs said.
According to Phivolcs, pyroclastic density currents, lahars, and sediment-laden streamflows along channels draining the edifice is possible.
“Civil aviation authorities must also advise pilots to avoid flying close to the volcano’s summit as ash from any sudden eruption can be hazardous to aircraft,” it says.
“Based on the current prevailing wind pattern, ash fall events may most likely occur on the south side of the volcano,” Phivolcs warned.
Also being monitored by Phivolcs are Batangas’ Taal Volcano and Negros Island’s Kanlaon Volcano, which are both under Alert Level 1 or low-level unrest.
For Taal, entry into Taal Volcano Island, which has been declared as a PDZ, especially the main crater and Daang Kastila fissures and occupancy. Boating on Taal Lake, is strictly prohibited. Likewise, Phivolcs advised against flying any aircraft close to the volcano.
For Kanlaon, entering the 4 kilometer PDZ is now prohibited. Phivolcs also advised against flying any aircraft close to the volcano.