|DOST-PHIVOLCS - MAYON VOLCANO BULLETIN 21 January 2018 8:00 A.M.|
ALERT LEVEL 3: MAYON VOLCANO BULLETIN UPDATED as of 21 January 2018 8:00 A.M.Past 24 Hours Activity: Quiet lava effusion from the new summit lava dome and lava collapse events characterized Mayon Volcano's eruptive.
Alert Level 3 remains in effect over Mayon Volcano,Mayon Volcano is currently still in a relatively high level of unrest and hazardous eruption is still possible within weeks or even days. The public is strongly advised to be vigilant and desist from entering the six (6) kilometer-radius Permanent Danger Zone (PDZ) and the 7-km Extended Danger Zone (EDZ) on the southern flanks due to the danger of rockfalls, landslides and sudden explosions or dome collapse that may generate hazardous volcanic flows.
Fourteen (14) rockfall events and ten (10) pyroclastic density currents or PDCs were recorded by Mayon's seismic monitoring network. Rockfall events were generated by the collapsing lava front and margins of the advancing lava flow on the Miisi Gully and by shedding from the summit dome onto the Bonga Gully. Currently, the Miisi lava flow has advanced to three (3) kilometers from the summit crater well within the Permanent Danger Zone (PDZ). Weak ash clouds were lofted from the rockfall events as well as from the persistent disintegration of lava on the advancing front of the Miisi lava flow before drifting to the southwest. During night time, crater glow with incandescent rock flow along Miisi gully was observed. Sulfur dioxide gas emission was measured at an average of 954 tonnes/day on January 20, 2018. Electronic tilt measurements indicate a sustained swelling or inflation of the edifice since November 2017, consistent with pressurization by magmatic intrusion.