THE Philippine Institute of Volcanology and Seismology (Phivolcs) clarified that the magnitude 6.6 earthquake that shook Cotabato and its neighboring areas is not an indication of any volcanic activity.
A magnitude 6.6 earthquake, with a depth of only seven kilometers, struck Mindanao at 9:04 a.m. Tuesday, October 25, with the epicenter located 25 kilometers southeast of Tulunan, Cotabato. It was the second tremor to hit Tulunan in about two weeks.
Following the tremor, various posts from netizens circulated online, warning people that Mount Apo is expected to explode after two previous earthquakes.
Photos of the supposed magma near the mountain also went viral.
But Phivolcs said although the nearest active volcanoes from the epicenter of Tulunan are Matutum Volcano and Parker Volcano, the recent and succeeding earthquakes "are tectonic in origin."
It assured the public that "as part of DOST-Phivolcs monitoring procedures for moderate to large earthquakes occurring near active volcanoes, the institute will closely monitor earthquake events in relation to any activity that may be associated with Matutum and Parker volcanoes."
Some netizens also clarified that the supposed magma is actually a "liquefaction," or a normal occurrence every after intense earthquake, saying it is only a saturated soil that loses its strength and stiffness in response to an applied stress like shaking during an earthquake.
Phivolcs-Davao science research assistant Chris Vidad said their office has also not reported any volcanic activity in Mount Apo, which is located between Davao City and Davao del Sur province and Cotabato.
Despite Mount Apo being a large solfataric, potentially active stratovolcano, Vidad said Phivolcs has not noticed any activities that would indicate its possible eruption.
"Although di natin masabi na may correlation siya ngayon doon sa recent paglindol dahil ang focus namin is more on the faults, we're closely monitoring the activity of Mount Apo (Although we cannot tell that it has a correlation on the recent earthquake since our main focus is on the faults, we're closely monitoring the activity of Mount Apo)," Vidad said in a phone interview.
He added that Phivolcs is also monitoring the activity of the mountain, since there are faults that slowly exist nearby. He added that they are still determining the faults' path to see if they are connected with Mount Apo.
Vidad advised the public to refrain from sharing unverified news, saying it would stir public panic.
Mount Apo is the highest mountain in the Philippines, with an elevation of 2,954 meters (9,692 feet) above sea level. The peak overlooks Davao City 45 kilometers to the northeast, Digos 25 kilometers to the southeast, and Kidapawan 20 kilometers to the west.
As of 12 a.m. Wednesday, October 30, Phivolcs has recorded 270 aftershocks, ranging from magnitude 1.5 to 6.1, following the magnitude 6.6 tremor that struck October 29. A total of 160 were plotted while the 50 others were only felt.
Phivolcs said aftershocks are expected to occur in the coming days or weeks.