Taal Volcano seismic activity increases; Alert Level 1 stays

LUCENA CITY — Taal Volcano in Batangas exhibited heightened seismic activity following a minor phreatic eruption on Saturday, according to the Philippine Institute of Volcanology and Seismology (Phivolcs).

In its Sunday morning bulletin, Phivolcs reported that the volcano triggerted 15 volcanic earthquakes and 14 volcanic tremors lasting from one to 28 minutes over the past 24 hours — the highest number of daily seismic events recorded so far this month.

Monitoring data showed that Taal Volcano logged a total of 145 volcanic earthquakes and 19 volcanic tremors from May 1 to 16.

Volcanic earthquakes are triggered by magma-related processes occurring beneath or near an active volcano, while volcanic tremors are continuous low-frequency seismic signals that may persist for more than a minute.

At 12:16 a.m. on Saturday, Taal Volcano generated a minor phreatic, or steam-driven, eruption that lasted about three minutes.

The event, locally known as “pusngat,” produced a plume reaching approximately 300 meters high.

Phivolcs defines a phreatic eruption as a “steam-driven explosion that occurs when water beneath the ground or on the surface is heated by magma, lava, hot rocks, or new volcanic deposits.”

Last month, Taal Volcano recorded nine minor eruptive events, consisting of four phreatomagmatic eruptions and five phreatic eruptions.

During the latest monitoring period, the volcano also emitted 1,641 metric tons of sulfur dioxide. Its plume rose up to 2,400 meters before drifting southwest, an activity Phivolcs classified as a “moderate emission.”

No upwelling of hot volcanic fluids was observed in the main crater lake on Taal Volcano Island at the center of Taal Lake.

Likewise, no volcanic smog, or vog, was detected.

Taal Volcano remains under Alert Level 1, indicating a state of low-level unrest that should not be interpreted as the end of volcanic activity or eruptive threats. /gsg