PHIVOLCS: 4 pyroclastic density currents recorded in Mayon Volcano

The Philippine Institute of Volcanology and Seismology (PHIVOLCS) said Mayon Volcano had four pyroclastic density current (PDC) events on Wednesday morning as it remained under Alert Level 3.

PHIVOLCS director Teresito Bacolcol said the PDCs occurred between 5 a.m. and 9 a.m., based on a report by Super Radyo dzBB’s Allan Gatus.

The highest amount was recorded at 8:58 a.m. with ash plumes reaching 100-meter high.

At 6 a.m., the PDC extended to 50 meters.

Despite this, PHIVOLCS said it sees no reason to raise Alert Level 4 in Mayon Volcano. Currently, Alert Level 3 remains hoisted over the active volcano in Albay due to intensified unrest or magmatic unrest.

PHIVOLCS’ Wednesday bulletin showed that Mayon Volcano had nine earthquakes and 147 rockfall events over the past 24 hours. 

Its sulfur dioxide emission also averaged 870 tonnes per day on Tuesday, September 19. It also generated a moderate 700 meter-tall plume, drifting west-southwest.

The slow effusion of lava from the volcano’s summit crater also continued, reaching 3.4 kilometers along the Bonga Gully (southeastern), 2.8 kilometers along Mi-isi Gully (south), and 1.1 kilometers along Basud Gully (eastern).

Collapses of the lava flow margins and of the summit dome likewise deposited debris still within 4 kilometers from the crater.

The Civil Aviation Authority of the Philippines (CAAP), meanwhile, extended the Notice to Air Mission (NOTAM) until Thursday morning due to the continued activities of Mayon Volcano.

Flights operating 11,000 feet from the surfaces of Mayon Volcano were prohibited starting 7:27 a.m. on Wednesday, to 6:20 a.m. on Thursday.

Entry into the six-kilometer radius of Mayon Volcano’s permanent danger zone is not allowed. Flying any aircraft close to the volcano is likewise prohibited. — Giselle Ombay/RSJ, GMA Integrated News