Bulusan Volcano Rumbles: 49 Earthquakes Recorded, PHIVOLCS Warns of Possible Sudden Eruption
Bulusan Volcano in Sorsogon province is showing signs of unrest after the Philippine Institute of Volcanology and Seismology (PHIVOLCS) recorded 49 volcanic earthquakes between February 26 and March 2 — a significant spike in seismic activity that has put nearby communities on alert.
Of the 49 events, 16 were classified as volcano-tectonic earthquakes caused by rock fracturing at depths of 3 to 6 kilometers beneath the volcano's northern and southeastern flanks. While PHIVOLCS is maintaining Alert Level 0, meaning no magmatic eruption is forecast, the agency issued a stark warning: the increased seismicity could signal hydrothermal processes that may lead to a sudden phreatic (steam-driven) eruption.
Degassing activity from the summit crater has been described as weak to moderate, and the most recent sulfur dioxide measurements on February 26 showed emission levels too low to be detected. Despite these relatively calm surface indicators, the underground rumbling tells a different story.
Bulusan, standing at 1,565 meters above sea level, is one of the Philippines' most active volcanoes. Its eruptive history is dominated by short-lived phreatic explosions that can shoot ash plumes, ballistic rocks, and cause localized ashfall — dangerous even without flowing lava. PHIVOLCS reminded the public that entry into the 4-kilometer Permanent Danger Zone remains strictly prohibited.
Local government units have been advised to review their emergency and contingency plans in case the alert level gets raised. Civil aviation authorities were also warned to keep pilots away from the volcano's summit, as sudden ash eruptions can pose serious hazards to aircraft.
Source: The Watchers
