The Philippine Institute of Volcanology and Seismology recorded a “swarm” of at least 15 earthquakes in Central Mindanao on Saturday with the strongest, felt at magnitude 5, damaging 54 houses and a church in North Cotabato.
The strongest quake struck at 12:26 p.m. and its epicenter was located 14 kilometers south of Kidapawan City in North Cotabato at a depth of 11 kilometers, Philvolcs said.
It was part of a swarm of earthquakes that began at 5:59 a.m. with a 4.4-magnitude tremor followed by nine other quakes, but the only ones that could be felt were the initial one, the magnitude 4.7 earthquake at 7:09 a.m. and he 5.0-magnitude at 12:26 p.m.
But there were actually other earthquakes at 12:59 p.m. (3.8 magnitude), 1:33 p.m. (2.4 magnitude), 1:35 p.m. (3.5 magnitude), 1:41 p.m. (3.3 magnitude), 2:17 p.m. (3.2 magnitude), 3:04 p.m. (3.3 magnitude) and 3:19 p.m. (3.0 magnitude).
In a similar evening in October last year, a swarm of 14 earthquakes jolted Marinduque province and caused some alarm, but Philvocs director Renator Solidum said earthquake swarms are quite common and they happen without people even knowing.
Aside from the 10 quakes recorded in North Cotabato, there were also seven others recorded in Sultan Kudarat, Leyte, Southern Leyte, and Davao Occidental but only 5 reported felt intensities.
Meanwhile, Phivolcs supervising science specialist Angelito Lanuza reiterated there was no reason for people in Zamboanga Peninsula and parts of the Autonomous Region in Muslim Mindanao to panic after Solidum said a movement of the Sulu Trench could trigger another tsunami in Western Mindanao.
“The movement of the Sulu Trench would be dangerous because the trench is situated off Sulu Sea that could trigger big waves reaching up to Palawan, especially its eastern portion,” he told the Manila Standard.