Bulusan shows signs of unrest

Fifty volcanic earthquakes were recorded in the Bulusan Volcano according to the latest bulletin issued by the Philippine Institute for Volcanology and Seismology (Phivolcs) on Saturday, 24 May.

The volcano, located in the province of Sorsogon in the Bicol Region, also emitted 438 tonnes of sulfur dioxide on Friday and released voluminous reaching 100 meters tall before drifting west-southwest and west-northwest.

The volcano’s edifice remains inflated, indicating an accumulation of magma or volcanic glasses.

Phivolcs warned citizens in the area that sudden steam-driven or phreatic eruptions may occur. A phreatic eruption occurs when water comes into contact with hot volcanic materials such as rocks or gases, which, in turn, produces steam, ash, and fragmented volcanic materials.

Entry into the 4-kilometer radius Permanent Danger Zone, entry without vigilance into the Extended Danger Zone, and flying any aircraft close to the volcano remains prohibited.

Bulusan last erupted on 28 April, with activity lasting approximately 24 minutes prompting Alert Level 1 to be raised, indicating low-level volcanic unrest.

Meanwhile, Taal Volcano in the province of Batangas, also at the same alert level, registered 19 volcanic earthquakes in the last 24 hours. It also emitted weak plumes that rose as high as 750 meters before drifting southwest and northwest.

Ten volcanic tremors lasting two to four minutes were recorded during the same period.

On top of phreatic eruptions and volcanic earthquakes, Phivolcs warned of potential minor ashfall and the risk of hazardous gas accumulation for communities living near Taal’s vicinity.