MANILA, Philippines - After spewing ash, lava, pyroclastic material for weeks, Philippines’ most active volcano, Mayon, erupted on Tuesday.
State volcanologists said on Tuesday that the phreatomagmatic eruption lasted eight minutes and generated a dense, five-kilometre tall column of volcanic ash.
The massive eruption was followed by two explosion-type earthquakes, several tremors and rockfall events that went on throughout the day.
According to the latest bulletin by the Philippine Institute of Volcanology and Seismology (PHIVOLCS), the eruption took place at 12:43 p.m. and emitted a cloud of volcanic ash that covered the towns of Guinobatan, Camalig, Oas, Polangui, and Iriga City.
The bulletin added that the region witnessed two explosion-type earthquakes, 15 tremor events, 35 rockfall events and two pyroclastic flows from lava collapse events, recorded by Mayon’s seismic monitoring network.
On Tuesday, five instances of “intense but sporadic” lava fountaining took place, which lasted between three to 30 minutes from 9:37 p.m. Monday to 5:25 a.m. Tuesday.
Further, the bulletin added that the lava fountains from these episodes reached 500 to 700 meters high and produced ash plumes that went as high as 2.5 to 3 kilometres above the crater.
Late last week, authorities had imposed the alert level 4, which is one level away from the highest alert - meaning a hazardous eruption is underway - continues to remain in place over the restive volcano.
On Tuesday, the danger zone was extended to eight kilometres from seven kilometres.
Authorities said that the eruption also generated pyroclastic density currents (PDCs) or flows on several gullies and rivers within four kilometres of the summit vent, and was followed by a minor degassing event at 5:51 p.m. that produced a 500 meter-high ash plume.
They added that lava flows at the Miisi and Buyuan gullies have advanced three kilometres and 200 meters from the summit crater.
Meanwhile, state volcanologists also said that the volcano is emitting sulfur dioxide gas at an average rate of 992 tonnes per day.
This, however, was before the phreatomagmatic eruption.
Since January 13, when the volcanic activity increased, and hazardous eruption looked imminent, residents fled the town but had returned in recent days.
The eruption, however, sent thousands of these residents fleeing again.
As of Tuesday morning, authorities confirmed that almost 36,000 people have fled to safety, while the Mayon continues to spew lava and generate ash.
Officials also warned residents to wear face masks, or damp cloth over their nose and mouth, and to stay indoors.
A central Philippine province suspended work in public and private offices in at least three towns as a heavy fall of ash hit urban areas.
The Civil Aviation Authority of the Philippines said it shut down the Legazpi airport in Albay province because of ashfall, which affected nine international and 16 domestic flights.
Albay’s governor and chairman of its disaster agency, Al Francis Bichara, said he had suspended office work in three towns due to the thick ashfall.