In the past 24-hour period, the Mayon Volcano Network recorded seven (7) volcanic earthquakes and three hundred nine (309) rockfall events based on seismic and visual observations. Very slow effusion of lava from the summit crater emplaced lava flow and collapse debris on the Mi-isi (south) and Bonga (southeastern) gullies within approximately a kilometer from the crater. Seven (7) dome-collapse pyroclastic density current (PDC) that lasted four (4) minutes was also detected via seismic signals and was visually observed. Thin ash from the rockfalls and continuous moderate degassing from the summit crater produced steam-laden plumes that bent and crept downslope before drifting general east. Fair crater glow or “banaag” and incandescent rockfall shed from new fluidal lava at the summit of Mayon Volcano was observed. Sulfur dioxide (SO2) emission averaged 149 tonnes/day on 13 June 2023. Short-term observations from EDM and electronic tiltmeter monitoring show the upper slopes to be inflating since February 2023. Longer-term ground deformation parameters based on EDM, precise leveling, continuous GPS, and electronic tilt monitoring indicate that Mayon is still inflated, especially on the northwest and southeast.
Alert Level 3 is maintained over Mayon Volcano, which means that it is currently in a relatively high level of unrest as magma is at the crater and hazardous eruption is possible within weeks or even days. It is therefore recommended that the 6-km radius Permanent Danger Zone (PDZ) be evacuated due to the danger of PDCs, lava flows, rockfalls and other volcanic hazards. Increased vigilance against pyroclastic density currents, lahars and sediment-laden streamflows along channels draining the edifice is also advised. Heavy rainfall could generate channel-confined lahars and sediment-laden streamflows in channels where PDC deposits were emplaced. 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. Based on the current prevailing wind pattern, ash fall events may most likely occur on the south side of the volcano. DOST-PHIVOLCS maintains close monitoring of Mayon Volcano and any new development will be communicated to all concerned stakeholders.
