Mayon's volcano's sustained reduction in sulfur dioxide emission, continuous surface inflation may lead to violent eruption

Mayon volcano

A sustained reduction in sulfur dioxide emission and continuous surface inflation of Mayon Volcano may lead to a violent eruption, the Philippine Institute of Volcanology and Seismology (Phivolcs) warned yesterday. Phivolcs-Bicol chief volcanologist Ed Laguerta issued the warning after Mayon's gas emission dropped to 308 tons last Thursday, way below the normal 500 tons per day in the past 48-hour monitoring period.

He said the reduction in sulfur dioxide emission could mean that the lava dome protruding at the summit of the volcano is gradually blocking the crater. "If Mayon's crater is clogged by lava dome, a violent eruption is very likely to happen," Laguerta told .

He said they are closely monitoring Mayon's gas emission to determine if the drop would be a prelude to a small or big eruption. But Laguerta noted that even a phreatic or ash explosion may be followed by bigger eruption once the deep-seated magma deposit is depressurized.

He added that the absence of volcanic quakes in the past three days is not an indication that Mayon has calmed down.

Laguerta dismissed the idea of lowering Mayon's alert level, saying that the 8,077-foot volcano's activity might only be in a lull and that a hazardous eruption is highly possible. Meanwhile, Albay Gov. Joey Salceda urged the Army teams to strictly enforce the no man's land policy within the six-kilometer and seven-kilometer extended danger zones around Mayon.

"With the recent developments in the abnormal behavior of Mayon, we really could not take chances," Salceda told . He said relief goods from the national government and some foreign donors continued to arrive in the province. Albay is spending at least P1.5 million a day to feed the over 12,000 families or 56,000 individuals housed in 40 evacuation centers in the province.

Phivolcs raised Mayon's Alert Level to 3 last Sept. 15. Earlier, Phivolcs director Renato Solidum advised the local government to prepare for a massive evacuation when Alert Level 4 is raised. "We cannot stop this because this will go up to Alert Level 4," he said.