Mayon Volcano Eruption Activity Monitored by PHIVOLCS (Update September 18, 2014)

On 18 September 2014, Philippine Institute of Volcanology and Seismology (PHIVOLCS) reported 142 VT earthquake events and 251 rockfall events during the past day on Mayon Volcano in the province of Albay, Philippines.

White steam plumes drifted to the south-southwest and rain clouds covered the summit. Sulfur dioxide (SO2) emission was measured at an 757 tonnes/day on 17 September 2014, after it had peaked at 2,360 tonnes/day on 06 September 2014. Ground deformation (precise leveling and tilt meters) during the 3rd week of August 2014 recorded edifice inflation.

PHIVOLCS issued the following alert on its website:

NOTICE OF INCREASE TO ALERT LEVEL 3:

In the past several hours, a noticeable escalation of unrest was recorded by the Mayon Volcano monitoring network. Since 5:00 AM to 8:00 PM today, 39 rockfall events that are ascribed to incipient breaching of the growing summit lava dome across the southeastern crater rim, and 32 low frequency volcanic earthquakes that indicate magma intrusion and/or volcanic gas activity, have been detected. Crater glow has become observable, indicating incandescence of the crater from molten lava and hot volcanic gas.

In view thereof, PHIVOLCS-DOST is now raising the alert status of Mayon Volcano from Alert Level 2 to Alert Level 3. This means that Mayon is exhibiting relatively high unrest and that magma is at the crater and that hazardous eruption is possible within weeks. It is therefore recommended that the 6-km radius Permanent Danger Zone (PDZ) around the volcano and the 7-km Extended Danger Zone (EDZ) on the southeastern flank be enforced due to the danger of rockfalls, landslides and sudden explosions or dome collapse that may generate hazardous volcanic flows. PHIVOLCS maintains close monitoring of Mayon Volcano and any new development will be communicated to all concerned stakeholders.

Update 1: According to the report from the Philippine Star, three cities and five towns covering 46 barangays are now under a state of calamity as the province prepares for the imminent eruption of Mayon. Twelve Army trucks evacuated at least 4,624 families, or 23,557 persons, from 16 barangays located within six to eight kilometers from Mayon’s crater.

Evacuated were residents of barangays Maninila, Muladbucad Grande, Muladbucad Pequeño and Tandarora in Guinobatan town; Canaway, San Isidro and Calbayog in Malilipot town; Anoling, Cabangan, Quirangay, Salugan, Sua and Tumpa in Camalig town; Baligang and Nasisi in Ligao City; and Magapo, Comon, Buang and Mariroc in Tabaco City.