Phivolcs: Another Kanlaon eruption possible, ground swelling detected
Kanlaon Volcano in Negros Island appears calm in this photo taken at 6:30 a.m. on Jan. 6.2025. Communities at the foot of the volcano were told to remain on guard as Alert Level 3 (high level of volcanic unrest) is still in effect. (PHOTO COURTESY OF JERICK RICAPLAZA)
MANILA, Philippines — Pressure may be building up and lead to another eruption of Kanlaon Volcano after the detection of more ground swelling, the Philippine Institute of Volcanology and Seismology (Phivolcs) reported on Saturday.
Kanlaon Volcano erupted last Dec. 9, producing a voluminous plume that rose to 3,000 meters above the vent and drifted west-southwest.
This prompted Phivolcs to raise Alert Level 3.
“Ground deformation monitoring by the Kanlaon Volcano Network (KVN) has been recording a pronounced inflation or swelling of the middle to upper portion of the eastern edifice since yesterday evening,” Phivolcs explained in its advisory.
According to state volcanologists, the Upper Pantao Observation Station – sitting at 1,056 meters above sea level – recorded an “abrupt and sharp” increase in the tilt of the eastern side of Kanlaon Volcano since 7:20 p.m. on Friday, Jan. 10.
Article continues after this advertisement“[This indicates] a sudden pressurization within the upper portions of the edifice,” it explained.
Article continues after this advertisementPhivolcs also noted more swelling on the volcano’s southeastern side since the last week of December 2024 and less swelling on its western side since the first week of January 2025.
“These ground deformation parameters are largely similar to those recorded prior to the 9 December 2024 eruption, which was also preceded by a drop in SO2 (sulfur dioxide) emission,” Phivolcs said.
According to the agency’s data, Kanlaon Volcano emitted 5,763 tonnes of SO2 on Friday, Jan. 10, which was close to the average daily amount of emissions since the June 2024 eruption.
Phivolcs, however, recorded a significant drop in the SO2 emissions on Thursday, Jan. 9, with only 2,029 tonnes.
“The overall parameters may indicate that the shallow magma conduit of the volcano is undergoing pressurization that may lead to an eruption broadly similar to the 9 December 2024 event,” Phivolcs warned.
