HUNDREDS of people were displaced yesterday as Bulusan Volcano in Sorsogon erupted again.
The ash column from the phreatic or steam-driven eruption was estimated to be a kilometer high, said Renato Solidum, director of the Philippine Institute of Volcanology and Seismology (Phivolcs).
Ashfall reached at least 17 barangays in three towns. These are Cogon, Inlagadian, San Juan, Tulay in Casiguran town; Añog, Aroroy, Bacolod, Buraburan, Calateo, Lajong, Mabini, Puting Sapa, Tublijo in Juban; and Incarizan, Pili, Sta. Elena, Tula-tula in Magallanes town.
Juban town municipal disaster risk reduction officer Arian Aguallo said almost all areas of the town were affected by ashfall. “There are more barangays affected now,” he said.
Phivolcs said wind-drifted ash was reported in Sorsogon City and in Pilar town across Sorsogon bay, and as far as Anislang, Daraga in Albay towns or about 50 km northwest of Bulusan.
Phivolcs said the 18-minute phreatic eruption occurred at 3:37 a.m. and was recorded as an “explosion-type earthquake.”
It said shaking was felt at Intensity III by residents of Barangay Añog in Juban town, and Intensity II in Barangay Inlagadian in Casiguran town.
It said rumbling sounds accompanying the eruption were reported by witnesses in several barangays in Juban and Gubat towns.
It said a “brief incandescence at the base of the eruption plume” was reported in Barangay Inlagadian in Casiguran town.
“By daybreak, multiple active vents at the summit could be observed spewing ash and steam to a height of at least 500 meters before being drifted to the northwest,” Phivolcs said.
“In the morning, six vents — the major crater called Blackbird, three explosion pits on the summit, and the lateral vents on the northwest and north sides of the summit — were actively degassing short plumes which entrained ash until at least 9 in the morning,” Phivolcs also said.
The agency said the plumes dispersed into a long veil of ash, extending several kilometers to the northwest.
“This period of ‘ashing’ was accompanied by very weak sporadic volcanic tremor. Degassing of steam-laden plumes continues while the Blackbird crater generates a thin haze of ash upon the upper northwestern slopes,” it also said.
Phivolcs also said Bulusan Volcano remains under Alert Level 1 (low-level unrest), which was declared on June 5 shortly after making a similar phreatic eruption.
Solidum said yesterday’s eruption was stronger compared to the week before. He said Phivolcs recorded more than 100 volcanic earthquakes since the first eruption.
He also said yesterday’s phreatic eruption was similar to events the volcano had in the past decades.
“But we are not discounting the possibility that magma will come into play,” he said, adding the last time Bulusan Volcano had a magmatic eruption was more than 200 years ago.
“At present, what we saw are phreatic eruptions,” added Solidum, referring to the June 5 and yesterday’s eruptions.
Solidum said there are no indicators magma from the beneath the volcano is rising. He said the entire volcano edifice will be inflated if there is magma movement.
At the moment, Solidum said, Phivolcs is not seeing a possibility this would lead to a major eruption.
Mark Timbal, spokesman of the National Disaster Risk Reduction and Management Council, said initial information from the ground showed about 103 families or about 403 individuals from Juban were evacuated.
He said the displaced families were mostly the same people who were displaced during Bulusan Volcano’s eruption on June 5. The evacuees returned to their residents a few days ago.
Timbal reiterated the NDRRMC call to local government units not to allow any activity within the four-kilometer danger zone.
He also asked residents to wear face mask when they are going out of their homes.
