Amid the recent series of strong earthquakes across the country, the Department of Science and Technology (DOST) on Sunday reminded that such occurrences are not unusual, noting that the Philippines experiences around 30 earthquakes every day.
"There have been instances when there were big earthquakes that occurred one after the other," DOST Secretary Renato Solidum Jr. said in an interview.
"Although of course now, with the many instruments around the country and being aware through social media, it is easy for our countrymen to find out what is happening in other areas," he added.
Solidum explained that the frequent seismic activity is due to the country's location along multiple active faults on land and at sea, as well as major trenches where tectonic plates collide.
"Each day, at least 30 earthquakes are recorded by DOST-PHIVOLCS (Philippine Institute of Volcanology and Seismology)," he said. "It's not surprising that strong quakes occasionally strike different parts of the country."
Most of these daily tremors are too weak to be felt. "Magnitude 6 or higher quakes are rare, but they do happen every year," Solidum said. "Some just occur too far offshore to cause significant damage."
Recent seismic events include the magnitude 6.9 earthquake that hit Bogo City, Cebu, on September 30, damaging several heritage churches and killing at least 75 with over 1,000 injuries.
On October 10, two major quakes -- magnitude 7.4 in the morning and magnitude 6.8 in the evening -- struck near Manay, Davao Oriental. PHIVOLCS described these events as a "doublet earthquake" or two closely timed quakes in the same epicenter.
"Sometimes it's not just two movements of the ground but more -- those are called multiplets," Solidum explained. "That's actually better than one long, continuous quake."
Another quake, magnitude 6.0, struck off Cagwait, Surigao del Sur, on Saturday night (October 11). No damage has been reported so far from this seismic activity, according to the Provincial Disaster Risk Reduction and Management Office (PDRRMO).
Evaluations were also conducted in Cagwait, Tandag and other coastline communities. Residents eventually returned to their homes after the tsunami warnings were lifted.
The Surigao del Sur PDRRMO conducted an augmentation support to the hospital after patients were evacuated to tents following the earthquake. The Surigao del Sur emergency operation center remains active and continues to receive reports from local government units within the province.
Solidum also cautioned against running during earthquakes, noting that he has seen videos of people doing so, which may lead to further accidents.