Phivolcs: Seismic activity at Taal up

MANILA, Philippines - The Philippine Institute of Volcanology and Seismology (Phivolcs) yesterday reported a “noticeable increase” in seismic activity, recording 20 volcanic earthquakes, at the Taal Volcano in Batangas province.

In the bulletin issued yesterday, Phivolcs said that apart from the volcanic earthquakes they also noticed that the water temperature at the main crater of the lake slightly went up from 29.8 degrees Celsius to 30.1 degrees Celsius.

Another manifestation was the increase in carbon dioxide. “This large rise in CO2 concentration indicates gas release from the magma at depth,” it added.  

The gas measurements conducted at the Taal Main Crater Lake last January, February and March, yielded carbon dioxide (CO2) emission values of 2,250 tons per day (t/d), 1,875 t/d and 4,670 t/d, respectively.

Phivolcs added that the ground deformation survey (precise leveling) conducted around the volcano island from April 5 to 11 showed that the volcano edifice is slightly inflated as compared to the Feb. 2 to 9 survey.

The warning of Alert level 2 remains hoisted over Taal Volcano meaning that magma has been intruding toward the surface, as manifested by CO2 being released in the Main Crater Lake and increase in seismic activity.

Considering these observations, Phivolcs reiterated its advise to the public that the Main Crater, Daang Kastila Trail and Mt. Tabaro, which was the site of the 1965-1977 eruption, remains to be strictly off-limits.

The volcano monitoring office explained that “sudden hazardous steam-driven explosions may occur and high concentrations of toxic gases may accumulate. Breathing air with high concentration of gases can be lethal to humans, animals and even cause damage to vegetation.

It reminded that the entire Volcano Island is a permanent danger zone (PDZ), and permanent settlement in the island is strictly not recommended.