Mayon Volcano’s ongoing activity still shows no signs of slowing down after a month of increased unrest.
Between 5 a.m. on Saturday, July 8, and 5 a.m. on Sunday, July 9, the Philippine Institute of Volcanology and Seismology (Phivolcs) recorded three lava dome collapse-triggered pyroclastic density currents (PDC) lasting 1.5 to two minutes, one lava front collapse-triggered PDC producing a 500-meter-high light brown plume, 303 rockfall occurrences, and 26 volcanic quakes.
Mayon Volcano's lava flows and collapse debris have been continuing slowly down the Mi-isi and Bonga gullies on the southern and southeastern flanks, respectively.
Rockfall and pyroclastic density current (PDC) occurrences were also observed in these gullies, as well as in Basud Gully on the eastern flank of the volcano.
Superheated degassing plume from Mayon crater’s intense emissivity was captured by an infrared camera at the Bical, Sto. Domingo Station in Albay province on June 28, 2023. (Phivolcs)
Phivolcs said lava flows have progressed by about 2.8 kilometers (km) and 1.3 km, respectively, along the Mi-isi and Bonga gullies, while collapsed debris has advanced by four km along the Basud Gully.
It also pointed out that the Mayon Volcano continues to emit a “moderate” amount of sulfur dioxide, producing a one-km-high steam-laden plume that drifted southwest and west-southwest.
Sustained unrest
Phivolcs has upgraded Mayon Volcano’s status twice in the past month, first to level 2 on June 5 and then to level 3 on June 8 due to “intensified magmatic unrest.”
As of Sunday, Mayon Volcano is still in a relatively high level of unrest and that a potentially hazardous eruption within weeks or even days is still be possible.
Phivolcs advised communities near the restive volcano to maintain increased vigilance against PDCs, lahars and sediment-laden stream flows along channels draining the volcano edifice, as heavy rainfall could cause channel-confined lahars and sediment-laden stream flows.
It has strongly advised that entry into the six-kilometer permanent danger zone be strictly prohibited.
Pilots were also asked to avoid flying close to the volcano because ash from a sudden eruption may pose hazards to aircraft.
According to Phivolcs, communities on the southern side of Mayon Volcano may most likely experience ash fall events based on the current wind pattern.