MAYON VOLCANO ADVISORY

18 July 2023

3:30 PM

This is a notice of increased activity from Mayon Volcano’s summit crater.

Since 16 July 2023, the Mayon Volcano Network has been recording a continuous series of weak low frequency volcanic earthquakes (LFVQs) totaling 573 events until present. Some of these LFVQs were detected by infrasound sensors and were reported to have produced audible rumbling sounds in the evening of 17 July 2023 and this morning. Based on seismic analyses, most of the events originated from a shallow source and are associated with rapid releases of volcanic gases. However, no visible changes in effusive activity at the summit crater and no significant increases in overall seismic energy release have been recorded. Sulfur dioxide (SO₂) emissions measured by campaign surveys have been increasing since 12 July 2023 and peaked at an average of 2,989 tonnes/day on 15 July 2023, with today’s (18 July 2023) emission measured at 1,945 tonnes/day.

DOST-PHIVOLCS reiterates that Alert Level 3 (increased tendency towards a hazardous eruption) still currently prevails over Mayon Volcano, but that seismic and degassing parameters have been undergoing changes that may progress into further activity. It is strongly recommended that the areas inside the 6 kilometer-radius Permanent Danger Zone remain evacuated, and that communities within the 7- and 8-kilometer radius be prepared in case current PDC activity worsens. Civil aviation authorities must also advise pilots to avoid flying close to the volcano’s summit as ash from eruptions can be hazardous to aircraft. DOST-PHIVOLCS maintains close monitoring of Mayon Volcano and any new development will be communicated to all concerned stakeholders.

DOST-PHIVOLCS