The Philippine Institute of Volcanology and Seismology (PHIVOLCS) issued a notice at 5:15 p.m. Sunday, May 26, of increased seismic activity at Kanlaon Volcano on Negros Island.
A total of 24 volcano-tectonic or VT earthquakes had been recorded by the Kanlaon Volcano Network between 1:35 p.m. and 4:30 p.m. on Sunday, PHIVOLCS said.
These earthquakes ranged in energy from ML 0.8 to ML 2.3 and occurred at depths of 0 to 6 kilometers beneath the western flank of the Kanlaon volcanic edifice.
Volcanic sulfur dioxide (SOz) gas emission from the summit crater has been elevated since January 1, averaging 1,291 ton a day, with the latest SOz measurement on Sunday averaging 2,003 ton/day. PHIVOLCS said.
Ground deformation data from continuous GPS and electronic tilt measurements have been recording an ongoing inflation that began between April and July 2023 and a longer-term inflation of the entire edifice since March 2022, it added.
While monitoring parameters in the past months have been consistent with shallow hydrothermal activity driven by degassing of deeper magma, ongoing VT earthquake activity indicates shallow rock-fracturing on the edifice which may lead to further unrest, PHIVOLCS said.
The public is reminded that Alert Level 1 prevails over Kanlaon.
Should the above uptrend in monitoring parameters persist, the volcano status may be raised to Alert Level 2 to warn of increasing unrest, PHIVOLCS said.
The public and local government units are strongly advised to be vigilant and refrain from entering the four kilometer Permanent Danger Zone due to increased chances of sudden and hazardous phreatic eruptions occurring without warning, it added.
Civil aviation authorities must also advise pilots to avoid flying close to the volcano’s summit as ejecta from any sudden phreatic eruption can be hazardous to aircraft, PHIVOLCS said.
PHIVOLCS said it is closely monitoring Kanlaon Volcano’s activity and any new development will be relayed to all concerned.*