MANILA, Philippines — The Philippine Institute of Volcanology and Seismology (Phivolcs) on Wednesday said that the summit crater of the Mayon volcano has been detected having a crater glow in the past two days.
In a 4 p.m. bulletin, Phivolcs said that the crater glow was likely caused by hot magmatic gases heating the overlying atmosphere.
The crater glow, Phivolcs added, suggests “the possibility that remnant magma may be quietly rising to the shallow levels of the edifice.”
Phivolcs further said that the volcano’s edifice was detected having slight swelling or inflation, which began in February 2019.
“These observations indicate that Mayon’s recent behavior has been mainly driven by changes occurring within magma already emplaced beneath the edifice rather than by renewed magma intrusion events,” Phivolcs said.
Dave Rivera, Phivolcs science research specialist, told INQUIRER.net in a phone interview that Mayon’s activity was “normal” since it is an active volcano.
Alert Level 2 remains hoisted over Mayon, meaning it is at a “moderate level of unrest.”
“It is therefore strongly recommended that entry into the six kilometer-radius Permanent Danger Zone and a precautionary seven kilometer-radius Extended Danger Zone in the south-southwest to east-northeast sector, stretching from Anoling, Camalig to Sta. Misericordia, Sto. Domingo, should be strictly prohibited,” Phivolcs said.
The agency further warned that ashfall, sudden explosions, lava collapse, and pyroclastic density currents can occur “without warning,” and can threaten areas in the upper to middle slopes of Mayon.
“People residing close to these danger areas are also advised to observe precautions against rockfalls, pyroclastic density currents, and ashfall. Active stream/river channels and those identified as perennially lahar-prone areas on all sectors of the volcano should also be avoided especially during extreme weather conditions when there is heavy and prolonged rainfall,” Phivolcs explained.
In January 2018, Mayon had an eruption that sent a huge gray column of lava fragments, ash, and steam 10 kilometers into the sky. During that time, it prompted Phivolcs to raise Alert Level 4 over Mayon.