LEGAZPI CITY, Oct. 13 (PNA) -- After almost a month lull, Mayon is now showing signs of possible big eruption, an official of the Philippine Institute of Volcanology and Seismology (Phivolcs) said Monday.
"Once the seismicity continues to accelerate, this is the signal that will compel the Phivolcs to elevate the alert level from 3 to 4 as eruption will likely to happen anytime," Dr. Winchelle Ian Sevilla, Phivolcs supervising science and research specialist, said.
Sevilla said the conduit is fully loaded now -- only that the crater is clogged with lava dome.
"Once the seismicity continues to increase, this is the signal for us to raise alert level 4 as this means that magma is accelerating towards the crater,” he said.
For 29 days after Phivolcs raised alert level 3 on Mayon due to unrest, the volcano exhibited a period of lull. But on Sunday a small quantity of lava flowed from the summit, which was classified by Phivolcs as a quiet stage of eruption.
And as the Phivolcs is strictly monitoring the quiet stage of eruption, Sevilla said, they are expecting a bigger explosion any moment as big volume of fresh magma has accumulated, as indicated by the inflated edifice of the volcano for the past few weeks.
Ed Laguerta, Phivolcs resident volcanologist, said the lull period exhibited by the restive volcano is an indication of "calm before the storm."
Overtime, since the volcano’s unrest, fresh magma build up is calculated at about 40 million cubic meters.
These new volcanic materials will be added to the 30 million cubic meters ejected by the volcano during its last eruption.
Mayon volcano's last phreatic eruption took place in May 7, 2013, which killed four foreigners and one Filipino tour guide.
On Sunday, Defense Secretary Voltaire Gazmin, National Disaster Risk Reduction Management Council chair, directed military officials to ensure the zero-casualty goal of the government.
Gazmin's last-minute directive was done at the Tactical Operations Group 5-Philippine Air Force shortly before his return flight to Manila after the Food Caravan.
Army Col. Raul Farnacio, commanding officer of the Army’s 901st Infantry Brigade and head of the Team Albay Bayanihan, said the are working round the clock to ensure the safety of the people living at the foot of the restive volcano.
The Philippine Army and the Philippine National Police in Bicol, specifically in Albay, are patrolling within the danger zones of Mayon volcano. But despite of the strict policy of the government, numerous farmers tried to sneak in to harvest their agricultural crops in the no-man’s land area to support and send their children to school.
Sevilla reiterated the warning to the public not to venture inside the six-kilometer permanent danger zone and the 7-km extended danger zone as Mayon volcano may erupt anytime.
While only two volcanic earthquakes were recorded during the past 24-hour observation period and moderate-to-voluminous emission of white steam plumes drifting northeast was observed with an average of 420 tons of sulfur dioxide, ground deformation, however, showed continuous inflation at the base of the edifice during the August to October precise leveling surveys. (PNA) LAM/FGS/RBB/CBD/UTB