Alert level 2, however, still in place
(Eagle News) — The Philippine Institute of Volcanology and Seismology on Tuesday, May 18, warned against Taal’s “elevated unrest” after over 200 earthquakes were monitored at the volcano in 24 hours.
PHIVOLCS said the 288 quakes at the volcano, which remains on alert level 2, included 39 low-frequency volcanic earthquakes and 249 volcanic tremor events with durations of one to 20 minutes, and low-level background tremor that has persisted since April 8.
“Most of these earthquakes were very shallow and generated within five (5) kilometers beneath Taal Volcano Island or TVI and northeast Taal Lake,” PHIVOLCS said.
According to PHIVOLCS, an upwelling of hot volcanic fluids in the main crater lake and “active degassing from fumaroles on the main crater that produced 300-meter-tall steam-laden plumes” were also observed since daybreak.
Sulfur dioxide emission averaged 2,214 tons on May 17.
“Electronic tilt monitoring recorded a slight but very abrupt inflation of Taal Volcano Island that began yesterday, while longer-term ground deformation parameters from electronic tilt, continuous GPS and InSAR monitoring continue to record a very slow and steady inflation and expansion of the Taal region that began after the January 2020 eruption,” PHIVOLCS said, noting that these parameters indicate “persistent magmatic activity at shallow depths beneath the edifice.”
According to PHIVOLCS, while the alert level 2 remains over the volcano, volcano conditions remain unstable.
PHIVOLCS reiterated its recommendation for the entry into Taal Volcano Island, Taal’s Permanent Danger Zone or PDZ, especially the vicinities of the main crater and the Daang Kastila fissure, and occupancy and boating on Taal Lake should remain prohibited.
“(Department of Science and Technology)-PHIVOLCS reminds the public that at 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,” PHIVOLCS said.
Local government units were also advised to “continuously assess and strengthen the preparedness of previously evacuated barangays around Taal Lake in case of renewed unrest.”
