Seismic activity surges at Taal Volcano
The Philippine Institute of Volcanology and Seismology (Phivolcs) reported on Tuesday, October 7, 2025, a noticeable increase in seismic activity at Taal Volcano in Batangas province. (Photo courtesy of Jillian Dumas.)
LUCENA CITY — The Philippine Institute of Volcanology and Seismology (Phivolcs) reported on Tuesday a noticeable increase in seismic activity at Taal Volcano in Batangas province.
In its morning bulletin, Phivolcs said 19 volcanic earthquakes were recorded over the past 24 hours — a sharp rise from the seven logged the previous day.
From Oct. 1 to 7, a total of 48 volcanic earthquakes and four tremor episodes were recorded. In comparison, Phivolcs documented 189 volcanic earthquakes and 129 tremors throughout September.
READ: Taal Volcano logs 2 eruptions, 10 quakes, 4 tremors in 24 hours
According to Phivolcs, volcanic earthquakes are generated by active volcanoes and can be identified by distinct arrival times, durations, and amplitudes. Tremors, meanwhile, are continuous seismic signals characterized by low-frequency waves and may have regular or irregular patterns.
During the most recent monitoring period, sulfur dioxide (SO₂) emissions from Taal’s main crater were measured at 1,892 metric tons, with plumes rising 600 meters before drifting southwest. The emission was categorized as moderate.
No upwelling of hot volcanic fluids was observed in the main crater lake on Volcano Island, which lies at the center of Taal Lake. There was also no presence of volcanic smog (vog) during the observation window, according to Phivolcs.
Taal Volcano remains under Alert Level 1, indicating abnormal activity, but not yet at a level requiring evacuation.
Phivolcs warned, however, that Alert Level 1 does not mean that unrest has ceased or that eruptive activity is no longer a threat.
Residents and visitors are reminded to remain cautious and heed official advisories as monitoring continues./coa
