The Philippine Institute of Volcanology and Seismology (Phivolcs) reported Monday morning that 136 volcano-tectonic quakes hit the western flanks of Kanlaon in the past 24 hours.
Four of these tremors which took place at 1:01 a.m., 1:04 a.m., 1:34 a.m., and 2:06 a.m., were recorded by the Philippine Seismic Network at a magnitude range of 3.2 to 4.7.
These quakes, Phivolcs said, were felt at Intensities II to V in the cities of La Carlota and Bago in Negros Occidental, and in Canlaon City, Negros Oriental.
Phivolcs officer-in-charge director Renato Solidum Jr. said that their current interpretation of these series of quakes is due to the movement of faults on the lower part of Kanlaon’s crater which they are closely monitoring.
“Sa kasalukuyan ang ating interpretation diyan ay ang pagkilos ng fault ngunit mayroon ding mga kakaibang parameters na binibigay independently ang Kanlaon Volcano katulad ng bahgayang pagtaas ng sulfur dioxide at ang patuloy na pamamaga o inflation,” Solidum explained.
According to Phivolcs, hydrothermal or magmatic activity is occurring beneath Kanlaon’s edifice, as indicated by “slight deflation of the lower and mid slopes since January this year, and the continuing deflation on the lower slopes but inflation on the mid slopes since April 2020.”
Also on Monday, Phivolcs noted a moderate emission of white steam-laden plumes reaching up to 200 meters high at the vent of the volcano before drifting southwest, while levels of sulfur dioxide were measured at an average of 438 tonnes per day on June 13.
Meanwhile, the agency assured the public and nearby communities that it is “keeping a close watch” on the condition of the volcano and will inform authorities on further developments.
Alert Level 1 prevails over Kanlaon since it was raised last March, meaning that the volcano is at an “abnormal condition” and has entered a period of unrest.
Phivolcs reiterated its reminder to local government units that entry into the four-kilometer radius permanent danger zone must be strictly prohibited due to possible sudden and hazardous steam-driven or phreatic eruptions. (Alexandria San Juan)
