The Philippine Institute of Volcanology and Seismology (Phivolcs) on Saturday, April 3, said Taal Volcano continued to exhibit “increased unrest” as 125 volcanic earthquakes were monitored in its vicinity in the past 24 hours.
Of the number, seven were volcanic tremor episodes with durations of one to one and a half minutes, 114 low frequency volcanic earthquakes, three hybrid earthquakes, and one volcano-tectonic earthquake.
The state seismology bureau said activity at Taal’s main crater consisted of weak emission of steam-laden plumes from fumarolic vents that rose 30 meters.
It also measured a significant sulfur dioxide emission of 1854 tonnes/day on April 2, while temperature highs of 71.8 degrees Celsius and pH of 1.59 were last measured from the main crater lake on March 4 and February 12, respectively.
Ground deformation parameters also indicated “a very slow and steady inflation and expansion of the Taal region since after the January 2020 eruption,” as such “parameters may indicate increased magmatic activity at shallow depths beneath the edifice.”
With this, Phivolcs said Taal Volcano remained under Alert Level 2 or “Increased Unrest”, but it noted that such unrest has been elevating, and was under constant evaluation.
Under such alert level, 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 the volcano.
Phivolcs has recommended prohibiting the entry into Taal Volcano island, especially the vicinities of the main crater and the daang Kastila fissure, as well as occupancy and boating on Taal Lake.