Bacolod City – The Philippine Institute of Volcanology and Seismology reported ongoing increased ground deformation changes at the middle and lower southeastern slopes of Kanlaon volcano edifice.
PHIVOLCS resident volcanologist Ptolemy Mañego added that they logged six tectonic quakes so far this week.
The swelling on the middle and lower southeastern slopes of the volcano was discovered on June 18, and has been sustained since then, Mañegos said in a radio interview.
Considering that volcanic earthquake activity and elevated volcanic sulfur dioxide emission persists, PHIVOLCS, said in an advisory that the latest changes in ground deformation parameters could further indicate that magmatic intrusion beneath the edifice may be taking place, warning of increased chances of eruptive activity.
Of almost 9,000 families affected by the phreatic eruption of Kanlaon volcano on June 3, almost all have returned to their respective residences, according to the Department of Social Welfare and Development Office.
Only 10 families, composed of 34 individuals, remain at two evacuation centers, while another family, composed of five persons, are staying with relatives in La Castellana, Negros Occidental.
The 11 families that reside within the four-kilometer permanent danger zone of Kanlaon volcano were not yet allowed by the La Castellana municipal government to return to their respective homes, according to DSWD Field Office 6.
Mañego said those residing within the four kilometer permanent danger zone, have been strongly advised not to return to their respective homes, as Alert Level 2 remains in effect.
This means that there is current unrest driven by shallow magmatic processes that could eventually lead to explosive eruptions or even precede hazardous magmatic eruptions at the summit crater, according to PHIVOLCS.
It also advised communities living beside river systems on the southern and western slopes, especially those that have already experienced lahar and muddy streamflows, to take precautionary measures when heavy rainfall over the volcano has been forecast or has begun.
PHIVOLCS reported that Kanlaon emitted 2,556 tons of sulfur dioxide on July 13, while the normal sulfur dioxide emissions are 300 tons. (Gilbert Bayoran via The Visayan Daily Star)