|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 04 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.
Sporadic and weak lava fountaining, lava flow and degassing from the summit crater characterized Mayon’s activity yesterday. One event produced a 500-meter high ash plume and a low and weak lava fountain that lasted 37 seconds. Throughout the night, quiet lava effusion fed lava flows in the Miisi and Bonga-Buyuan channels and barrancos between these. The Miisi and Bonga-Buyuan lava flows have advanced to 3.2 kilometers and 4.3 kilometers, respectively, from the summit crater.
A total of fifty-five (55) volcanic earthquakes, most of which corresponded to sporadic and weak fountaining events, nine (9) rockfall events were recorded by Mayon's seismic monitoring network. Sulfur dioxide gas emission was measured at an average of 1,583 tonnes/day on 02 February 2018. Electronic tilt and continuous GPS measurements indicate a sustained swelling or inflation of the edifice since November and October 2017, consistent with pressurization by magmatic intrusion.