|PUBLIC ADVISORY: Notice of raising Mayon Volcano’s status from Alert Level 3 to Alert Level 4 as of January 22, 2018.|
PHIVOLCS: MAYON VOLCANO BULLETIN 20 February 2018 8:00 A.M.PHIVOLCS has raised the alert level to Alert Level 4 in effect over Mayon Volcano. The public is strongly advised to be vigilant and desist from entering the eight (8) kilometer-radius danger zone, and to be additionally vigilant against pyroclastic density currents, lahars and sediment-laden stream flows along channels draining the edifice.
SUMMARY | Alert Level 4 remains in effect over Mayon Volcano.
Mayon’s activity in the past 24 hours was characterized by sporadic and weak lava fountaining, lava flow and degassing from the summit crater. As of 04:05 AM this morning, fifty-six (56) discrete lava fountaining episodes that lasted five (5) to sixty-two (62) minutes were recorded by the seismic network. One (1) lava collapse pyroclastic density current (PDC) event that generated white to dirty white plume was visually observed yesterday at 6:16 AM along the Basud Gully. Lava flow sustained at 3.3 kilometers, 4.5 kilometers and 900 meters on the Miisi, Bonga and Basud Gullies, respectively, from the summit crater. Pyroclastic density currents or PDCs remained confined within the farthest recorded reaches of 4.6, 5.2 and 4.2 kilometers on the Miisi, Bonga and Basud Gullies, respectively.
A total of seventy-two (72) volcanic earthquakes, corresponding to lava fountaining and tremor events, was recorded by Mayon's seismic monitoring network. Sulfur dioxide (SO2) emission averaged 2,148 tonnes/day on 19 February 2018. Electronic tilt and continuous GPS still record sustained swelling or inflation of the edifice since November and October 2017, consistent with pressurization by magmatic intrusion.