LEGAZPI CITY: The downpour that pounded Albay recently may trigger a violent eruption of Mayon volcano, according to Ed Laguerta, chief volcanologist in the province.
He warned that a major explosion may occur anytime because of the heavy rains that soaked the province in the past days.
“With heavy downpour, even a small amount of water that will seep in to clog the volcano’s crater will cause a big explosion because as the crater is choked up, the stronger is the pressure,” Laguerta told The Manila Times.
He explained that after a phreatic explosion caused by rainwater leaching, a series of magmatic explosive eruptions will follow, depending on the pressure that may be ejected by the restive volcano. Phreatic eruptions typically include steam and rock fragments.
Since alert level 3 was raised by the Philippine Institute of Volcanology and Seismology (Phivolcs) on September 15, there has been a sudden drop in sulfur dioxide emissions and volcanic tremors, puzzling scientists.
On Saturday, only one volcanic earthquake and five rockfall events occurred.
“Magma is gradually ascending towards the crater but being blocked by big lava dome so this will lead to a big explosion anytime. That’s why we reiterated the six to seven extended kilometer danger zone to be a no man’s land to avoid casualties,” Laguerta said.
Laguerta warned that heavy rains may loosen rocks that may endanger low-lying areas.
“Remember that Mayon is sandy so any loose materials from her slopes will remobilize again. Mayon has the characteristic of destruction and self-healing,” he added.
More than 12,000 families or 51,125 individuals from 40 villages and two cities in Albay
remain in 46 evacuation centers, a government disaster agency said on Saturday.
The latest bulletin issued by the National Disaster Risk Reduction Management Council (Ndrrmc) said 45 barangays in Albay were placed under a state of calamity as Mt. Mayon continues to show signs of abnormal activity. The barangays include six villages in Legazpi and Ligao cities, eight in Tabaco City, six in the towns of Camalig and Daraga; five in Guinobatan and Sto. Domingo and three in Malilipot.
Classes in 29 schools within the six kilometer permanent danger zone which start from the center of the crater of Mt. Mayon remain suspended.
Weak to moderate emissions of white steam plumes were observed overnight, the NDRRMC said.
Sulfur dioxide was measured at 308 tons a day on Thursday while ground swelling was also noted, indicating that magma is rising.
WITH ANTHONY VARGAS