Mayon calm; Phivolcs lowers alert level

Mayon Volcano. INQUIRER.net FILE PHOTO/NOY MORCOSO

About a year after lava was seen flowing down Mt. Mayon in Albay, the Philippine Institute of Volcanology and Seismology (Philvolcs) lowered the alert level on the volcano.

The volcano was placed on Alert Level 3 in September last year when volcanic earthquakes became frequent and incandescent rock fall was observed. In December, it was placed on Alert Level 2. On Thursday, it was further lowered to Alert Level 1 due to continued decline in its overall activity.

Phivolcs said that the for the past six months, seismic activity had declined to a daily average of one volcanic earthquake.

“There has been no occurrence of low frequency earthquakes associated with magma or volcanic gas movement recorded. Such overall low-level seismicity indicates that there is currently no active transport of eruptible magma to the shallow levels of the volcano,” it said.

Other parameters such as ground deformation, gas emission and visual observation of the summit were also considered in lowering of the alert level.

This means “there is no likelihood of an eruption occurring” but said  “in the event of a renewed increase in any one or combination of the above monitoring parameters, the alert status may step up once again to Alert Level 2.”

Despite the notice, the public is still reminded to the six-kilometer permanent danger zone “due to perennial hazards of rock fall, avalanche, ash puff and sudden steam-driven or phreatic eruption at the summit area.”

“Furthermore, people living in valleys and active river channels are cautioned to remain vigilant against sediment-laden stream flows and lahars in the event of prolonged and heavy rainfall brought about by the advent of the rainy season,” Phivolcs said. Frances Mangosing / CB