• GILBERT P. BAYORAN
The Philippine Institute of Volcanology and Seismology (PHIVOLCS) has recorded increased seismic activity at the Kanlaon volcano in Negros Island, between 5 a.m. of September 4 and 7:50 a.m. Sept. 6.
PHIVOLCS logged 36 volcanic quakes, including 34 volcano tectonic, or VT earthquakes.
The earthquakes occurred at depths of 0 to 9 kilometers beneath the northeast flank of the Kanlaon range, it added.
PHIVOLCS is observing ground deformation data from the continuous GPS and electronic tilt measurements that has been recording short term inflation of the middle slopes since March 2023, and a longer term inflation of the entire edifice since March last year.
According to PHIVOLCS, volcanic sulfur dioxide gas emissions from the summit created an average of 412 tons a day on August, lower than the average emission of 623 tons a day, the previous month.
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 that fracturing at deeper levels is occurring and may possibly lead to further unrest, it further said.
With this development, PHIVOLCS said that Alert Level 1 still prevails over Kanlaon.
Should the uptrend in monitoring parameters persist, the volcano’s status maybe raised to Alert Level 2 to warn of increasing unrest, PHIVOLCS said.
It also strongly advised the public and local government units surrounding the Kanlaon volcano 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 a warning.
Civil aviation authorities also advised pilots to avoid flying close to the volcano’s summit.*
