A total of 72 volcano-tectonic (VT) earthquakes have been recorded by the Kanlaon Volcano Network between 12 a.m. and 8 a.m. on Monday, September 15, 2025.

According to the Philippine Institute of Volcanology and Seismology (PHIVOLCS), the strongest of these VT earthquakes was felt at Intensity I both in La Carlota City, Negros Occidental and Canlaon City, Negros Oriental. 

VTs are generated by rock fracturing processes and the increase in VT activity strongly indicates progressive rock-fracturing beneath the volcano as rising magma or magmatic gas drives a path towards the surface, PHIVOLCS pointed out.

Volcanic sulfur dioxide (SO2) gas emissions from the summit crater of Kanlaon based on standard measurements on September 14, 2025, averaged 2,338 tons per day, near the medium-term average of 2,417 tons per day since January 1, 2025. 

These parameters indicate that the blockage of volcanic gas emission, or closed-system degassing, may result in pressurization and swelling of the edifice potentially leading to moderately explosive eruption, PHIVOLCS added. 

“The public is reminded that Alert Level 2 prevails over Kanlaon, which means that the volcano is in a state of increased unrest.  The increase in VT events could lead to increased chances of steam-driven or phreatic eruptions or short-lived weak to moderately explosive eruptions occurring at the summit that could generate life-threatening volcanic hazards such as pyroclastic density currents or PDCs, ballistic projectiles, ashfall, rockfall and other,” PHIVOLCS underscored. 

Further, PHIVOLCS advised communities within the 4-km Permanent Danger Zone (PDZ) to strictly remain evacuated and those within the 6-km radius from the summit crater be vigilant and ready in case unrest worsens. 

“In addition, increased vigilance against potential syn-eruption lahars and sediment-laden streamflows in channels draining the edifice is strongly advised should intense rains occur during eruptive unrest. Civil aviation authorities must also advise pilots to avoid flying close to the volcano’s summit as ash from any sudden eruption can be hazardous to aircraft,” PHIVOLCS further said.