|This serves as a notice for the lowering of Mayon Volcano’s status from Alert Level 4 (hazardous eruption imminent) to Alert Level 3 (decreased tendency towards hazardous eruption).|
PHIVOLCS: MAYON VOLCANO BULLETIN 15 March 2018 8:00 A.M.SUMMARY | Alert Level 3 currently prevails over Mayon Volcano.
Mayon’s activity in the past 24 hours was characterized by a brief period of lava effusion, weak to moderate degassing from the summit crater, gravity-driven lava flow and general quiescence. One (1) lava fountaining event from 0831H to 0832H PST yesterday generated light gray ash plumes that rose 200m above the summit crater before drifting southwest. Lava flows could be observed at night to be moving downslope on the Miisi,Bonga and Basud Gullies within 3.3 kilometers, 4.5 kilometers and 1.9 kilometers of the crater, respectively.
A total of thirty one (31) volcanic earthquakes and thirty (30) rockfall events were recorded by Mayon's seismic monitoring network. Sulfur dioxide (SO2) emission was measured at an average of 1938 tonnes/day on 14 March 2018. A slight inflation of the lower flanks beginning 11 March 2018 was recorded by electronic tilt, consistent with results of Precise Leveling (PL) surveys on 03 - 06 March 2018. Overall ground deformation data indicate that the edifice is still swollen or inflated relative to pre-eruption baselines.