The Philippine Institute of Volcanology and Seismology (Phivolcs) announced on Monday that Mayon Volcano’s alert level has been raised from Level 1 (abnormal) to Level 2 (increased unrest) due to a significant rise in rockfall occurrences.
Phivolcs reported that the volcano has experienced a surge in rockfall events, with an average of 49 incidents recorded from 5 a.m. on June 4 to 5 a.m. the following day. This is a significant increase compared to the usual average of five daily rockfalls. In addition, since April 1, a total of 318 rockfall events and 26 volcanic earthquakes have been documented.
— PHIVOLCS-DOST (@phivolcs_dost) June 5, 2023
The volcano’s lava dome has also shown noticeable growth, expanding by approximately 83,000 cubic meters since February 23. In total, it has increased by nearly 164,000 cubic meters since August 20, 2022.
Phivolcs highlighted that the elevated sulfur dioxide emission is another concerning factor. The highest recorded emission of sulfur dioxide was 576 tonnes on April 29, with subsequent measurements averaging 162 tonnes as of May 23.
In their advisory, Phivolcs stated, “These low-level volcanic earthquakes, ground deformation, and volcanic gas parameters are overshadowed by recent steep increases in rockfall events, which may possibly lead to further dome activity.”
Under Alert Level 2, the ongoing unrest caused by shallow magmatic processes could potentially result in phreatic eruptions or serve as a precursor to a hazardous magmatic eruption.
To ensure the safety of the public, authorities urge residents to remain vigilant and refrain from entering the 6 km radius permanent danger zone surrounding the volcano. By adhering to this advisory, individuals can minimize risks associated with sudden explosions, rockfalls, and landslides.
In the event of ashfall affecting communities downwind of Mayon’s crater, residents are advised to cover their nose and mouth with a damp, clean cloth or wear a dust mask to protect themselves from potential respiratory problems.
Furthermore, Phivolcs has emphasized the importance of aviation authorities informing pilots to avoid flying in close proximity to the volcano’s summit. Any ash released during a sudden eruption can pose serious hazards to aircraft.