A short-lived phreatomagmatic burst and a high sulfur dioxide (S02) emission averaging 12,516 tonnes were recorded in the Taal Volcano on Monday, the Philippine Institute of Volcanology and Seismology (Phivolcs) reported on Tuesday.
The phreatomagmatic burst was recorded at 11:39 p.m. as a volcanic tremor event that lasted three minutes. This generated a plume 2,400 meters high.
Phreatomagmatic eruptions are caused by the interaction of magma and water.
Meanwhile, 10 volcanic earthquakes, including seven volcanic tremor events having durations of one to three minutes, and three low-frequency volcanic earthquakes, were also observed.
Volcanic quakes are caused by movements or eruptions of magma from the volcano.
Phivolcs Director Renato Solidum Jr. told the Philippine News Agency that the low number of volcanic quakes was observed from end of September until the third week of October.
“Most days during that period, the number of quakes was below 10,” he said.
The most recent increase in numbers, reaching over 100, happened on the second week of November, according to Solidum.
Alert level 2 (increased unrest) is maintained over the Taal Volcano, which means that 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 the Taal Volcano Island (TVI).
Entry into the TVI is strictly prohibited.
Phivolcs urge local government officials to continuously assess and strengthen the preparedness of previously evacuated barangays around Taal Lake in case of renewed unrest.