Taal Volcano rumbles again; 752 quakes detected

MANILA, Philippines — The Philippine Institute of Volcanology and Seismology (Phivolcs) warned on Wednesday about the increased possibility of a magmatic eruption after it observed a heightened level of seismic activity at Taal Volcano.

In an advisory, Phivolcs said that since the volcano started showing signs of unrest on Feb. 13, a total of 2,015 volcanic tremors, 734 low-frequency volcanic earthquakes and 18 hybrid earthquake events have been recorded by the Taal Volcano Network.

It also observed that tremors caused by the movement of magma have became the common type of earthquake since March 19.

It said that most tremors had been reported at shallow depths of less than 2 kilometers, though some large earthquakes were generated at a depth of 2 to 6 km beneath the island.

“The above parameters indicate that magma has been migrating across shallow depths beneath [the] Taal Volcano Island, increasing the [possibility] of magmatic eruption,” Phivolcs said.

It added that entry to Taal Volcano Island, Taal’s Permanent Danger Zone, the main crater and the Daang Kastila fissure, and boating on Taal Lake should be prohibited.

Hazards

Phivolcs also urged civil aviation authorities to advise pilots not to fly near the volcano to avoid the hazards it might pose to aircraft.

Taal Volcano has been under Alert Level 2 or increased unrest since March 9. This means that sudden steam-driven or phreatic explosions, volcanic earthquakes, minor ashfall or expulsion of volcanic gas may occur around the island.

“Overall seismic energy release has markedly increased since yesterday afternoon compared to previous seismic swarms. Sulfur dioxide gas emission in the previous week has been generally high with a peak of 1,184 tons per day on March 21,” Phivolcs said.

Taal Volcano Island’s ground deformation has remained steady and at slightly rising trends since February, it added.