The ongoing eruption of Mayon Volcano has caused volcanic ash to fall on parts of Albay, the Philippine Institute of Volcanology and Seismology (Phivolcs) said on Tuesday, July 11.
Thin ashfall is said to have been observed in the town of Camalig, as well as in Brgy. Mabinit in Legazpi City and barangays Budiao and Salvacion in the municipality of Daraga.
According to Phivolcs, ashfall is most likely to occur in areas south of Mayon Volcano due to current wind patterns.
The Mayon Volcano ejects massive pyroclastic density currents (PDC) towards the Basud Gully in Sto. Domingo town in Albay province around 5:30 p.m. on July 10, 2023. (Niño Luces/Manila Bulletin)
Unrest continues
Phivolcs warned on Monday, July 10, that “increased activity” was occurring at Mayon Volcano due to the frequency of pyroclastic density currents (PDCs) and rockfall occurrences.
Between 5 a.m., Monday, and 5 a.m., Tuesday, 38 PDCs, 511 rockfall events, three volcanic earthquakes were recorded by the Mayon Volcano Network.
“The PDCs were generated by partial collapses from the summit lava dome and the advancing front and margins of lava flows and travelled one to three minutes within four kilometers of the Basud, Mi-isi and Bonga Gulleys,” Phivolcs said.
“Very slow effusion of lava from the summit crater continued to feed lava flows and collapse debris on the Mi-isi and Bonga gullies as well as rockfall and PDCs on these and the Basud (eastern) Gullies,” it added.
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.
The Mayon Volcano also continued to emit “moderate” amounts of sulfur dioxide, producing an 800-meter-high steam plume that drifted southwest and south-southwest.
Alert Level 3 still in effect
Mayon Volcano remains under Alert Level 3, which means there is still an “increased tendency towards a hazardous eruption.”
Communities near the restive volcano were advised to maintain increased vigilance against 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.
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.”