Angelito Lanuza, senior science research specialist of the Phivolcs Seismological Observation and Earthquake Prediction Division (SOEPD), said that they have detected 80 aftershocks by 1 p.m. on Sunday, following the magnitude 5.7 temblor that jolted North Cotabato.
The aftershocks are anticipated to continue for several days as the result of the strong tremor, according to him.
At around 10 p.m., Saturday, the magnitude 5.7 earthquake, with its epicenter 10 kilometers northwest of Carmen town in North Cotabato at a depth of five kilometers, rocked the province causing injuries and damaging houses and infrastructure in the area.
The earthquake was felt at Intensity V (everybody feels the shaking) at its epicenter while it was felt at intensity IV (most of the people inside houses and buildings feel the movement) in Roxas town, Tacurong City, and Midsayap town. Intensity III (many people inside houses and buildings feel the shaking) was recorded in Misamis and Cotabato Cities, Tampakan town in South Cotabato and Makilala and Magpet towns in North Cotabato as well as in Valencia and Marawi Cities.
Phivolcs reported intensity II (people at rest would feel the shaking) in Mlang and Tulunan towns in North Cotabato, Camiguin Island, General Santos City, Malaybalay in Bukidnon; Misamis Oriental and Davao del Sur while intensity I (practically nobody felt the movement) was recorded in Dipolog City.
Lanuza said that the tremor was caused by the shifting of tectonic plates in one of the unnamed faults in the area.
Of the five aftershocks felt since Saturday night, a magnitude 4.9 quake recorded at 9:40 a.m. on Sunday, was the strongest. Intensity IV was felt at the epicenter of Carmen town in North Cotabato while Intensity II was felt in Matalam town of the province and Davao City.
Meanwhile, the agency dispelled threats of a tsunami from a magnitude 6.5 earthquake that hit Taiwan at around 5:43 UTC (1:43 pm Philippine time).
The epicenter of the temblor was placed by the US Geological Survey at 22 kilometers south-southeast of Buli, Taiwan, with a depth of 20 kilometers.
According to the 1:58 pm Phivolcs advisory, “No destructive Pacific-wide threat exists based on the historical and tsunami data. However, earthquakes of this size sometimes generate local tsunamis that can be destructive along coasts located within a hundred kilometers of the epicenter.”
It concluded, “There is no tsunami threat to the Philippines from this earthquake.”