THE Philippine Institute of Volcanology and Seismology (Phivolcs) yesterday reported an increase in the possibility of Taal Volcano erupting, based on an “elevated increase” in the volcano’s seismic activity.
The volcano in Batangas remains under alert Level 2 (increased unrest).
In an advisory, Phivolcs said it has recorded 2,015 volcanic tremors, 734 low-frequency volcanic earthquakes and 18 hybrid earthquake events at the volcano since February 13 when unrest began.
“Harmonic tremor associated with magma migration has become the dominant type of earthquake since 19 March 2021,” Phivolcs said.
It said most of the earthquake events occurred at shallow depths of less than two km, although some large earthquakes were generated in the deeper region of two to six km beneath the Taal Volcano Island (TVI) edifice.
“Overall seismic energy release has markedly increased since yesterday afternoon compared to previous seismic swarms,” Phivolcs said.
“Sulfur dioxide gas emission in the previous week has been generally high with a peak of 1,184 tonnes/day on 21 March 2021,” it added.
Phivolcs nevertheless said that ground deformation at the TVI and and Taal Caldera region “has remained steady and at slight inflationary trends” since last month.
“The above parameters indicate that magma has been migrating across shallow depths beneath TVI, increasing the possibilities of magmatic eruption,” Phivolcs said.
Phivolcs reminded the public that under alert Level 2, “sudden steam-driven or phreatic explosions, volcanic earthquakes, minor ashfall, and lethal accumulations or expulsions of volcanic gas can occur and threaten areas within and around TVI.”
Entry at the TVI, which is considered a permanent danger zone, is strictly prohibited.
“Local government units are advised to continuously assess and strengthen the preparedness of previously evacuated barangays around Taal Lake in case of renewed unrest,” Phivolcs said.
It said civil aviation authorities must advise pilots to avoid flying close to the volcano because particles from the volcano may pose hazard to aircraft.