The Philippine Institute of Volcanology and Seismology repeated its stern warning for people to not approach Taal Volcano island after it recorded increased seismic activity and movement of magma on the famous volcano in Batangas.
“A steam-driven or phreatic eruption is possible. It’s dangerous to people if they are on the island or on shorelines near the island,” Phivolcs Director Renato Solidum told ABS-CBN’s Teleradyo.
“Should there be a steam-driven explosion, because there’s no one on the island, it’s currently safe. It’s important that no one violates protocol,” he added.
Solidum said the volcano remains under alert level 2, the second-lowest in a five-step system.
“We need to monitor if the magma will come out, and if yes, if it will become explosive or slowly become lava,” he said.
“Because we can only see a small volume, it will not be like the 2020 explosion. It will become more explosive if the magma resupplies,” the Phivolcs chief added.
On Wednesday, the agency said Taal Volcano has become more active and could have a “magmatic” eruption soon.
The famous volcano in Batangas recorded 2,015 volcanic tremors, 734 low-frequency volcanic earthquakes and 18 hybrid earthquake events since February 13, as seismic activity in the area had an “elevated increase.”
The agency said that “harmonic tremor associated with magma migration” was the dominant type of earthquake since March 19.
There are two types of volcanic eruptions in terms of activity — explosive and effusive. Explosive eruptions are characterized by gas-driven explosions that propels magma and tephra. Effusive eruptions, meanwhile, are characterized by the outpouring of lava without significant explosive eruption.
Magmatic eruptions produce juvenile clasts during explosive decompression from gas release, geologists say. They range in intensity from the relatively small lava fountains on Hawaii to catastrophic Ultra-Plinian eruption columns more than 30 kilometers high, bigger than the eruption of Mount Vesuvius in 79 AD that buried Pompeii in Italy.
Taal’s sulfur dioxide gas emission in the previous week has been generally high with a peak of 1,184 tons per day last Sunday, the state seismology bureau noted.
These parameters indicate that magmatic eruption may be possible, it said.
“Ground deformation of TVI and the Taal Caldera region in general has remained steady and at slight inflationary trends since February 2021,” it said.
“The above parameters indicate that magma has been migrating across shallow depths beneath TVI, increasing the possibilities of magmatic eruption.”
It recommended that entry into Taal Volcano Island, Taal’s Permanent Danger Zone or PDZ, especially the vicinity of the Main Crater and the Daang Kastila fissure, and occupancy and boating on Taal Lake, must be strictly prohibited.
“Local government units are advised to continuously assess and strengthen the preparedness of previously evacuated barangays around Taal Lake in case of renewed unrest,” it said.
“Civil aviation authorities must advise pilots to avoid flying close to the volcano as airborne ash and ballistic fragments from sudden explosions and wind-remobilized ash may pose hazards to aircraft.”
