A total of 28 earthquakes were recorded at Taal Volcano in the past 24 hours, the Philippine Institute of Volcanology and Seismology (Phivolcs) said in its bulletin on Monday, Oct. 18.
The Taal Volcano Network recorded 28 volcanic tremor events having a duration of two to five minutes and low-level background tremor that has persisted since July 7.
Phivolcs said the activity at the main crater was also dominated by the upwelling of hot volcanic fluids in its lake which generated plumes 1,800 meters tall.
Sulfur dioxide (SO2) emission was measured at 11,432 tons on Sunday, Oct. 17.
Taal Volcano's highest SO2 emission was 25,456 tons on Oct. 5.
"Based on ground deformation parameters from electronic tilt, continuous GPS and InSAR monitoring, Taal Volcano Island has begun inflating in August 2021 while the Taal region continues to undergo very slow extension since 2020," Phivolcs said.
It reminded the public that Taal Volcano remains under Alert Level 2, which means that the current SO2 parameters indicate high levels of magmatic degassing from the main crater that could drive explosive activity.
"At Alert Level 2, sudden steam- or gas-driven explosions, volcanic earthquakes, minor ashfall, and lethal accumulations or expulsions of volcanic gas can occur and threaten areas within and around TVI," it pointed out.
The volcano has been under Alert Level 2 since July 23, 2021.
Phivolcs reiterated that entry into the Taal Volcano Island, which is a permanent danger zone, especially the vicinities of the main crater and the Daang Kastila fissure, is strictly prohibited.
Boating on Taal Lake is also be prohibited, it added.
Phivolcs advised the concerned local government units to continuously assess and strengthen the preparedness of previously evacuated barangays around Taal Lake in case of renewed unrest.