3 earthquakes hit North Cotabato

By: Jeannette I. Andrade - 11 years ago

Source: Phivolcs website

MANILA, Philippines — A series of earthquakes, the strongest recorded at a magnitude 4.5, jolted parts of North Cotabato Sunday morning.

The Philippine Institute of Volcanology and Seismology (Phivolcs) said that the three tremors, which happened several minutes apart, were related to a magnitude 5.7 earthquake, which shook the province on June 1, 2013.

Phivolcs supervising science research specialist Angelito Lanuza said that the quakes had been triggered by the movement of an unnamed local fault.

He pointed out that it was the same fault that moved when North Cotabato was jolted in 2013 by a magnitude 5.7 temblor, which had its epicenter at 13 kilometers northwest of Carmen, North Cotabato. The earthquake was felt at Intensity 6 in parts of North Cotabato, Sultan Kudarat, Lanao del Sur, Misamis Oriental, South Cotabato, Maguindanao, Bukidnon, Davao del Sur and Zamboanga del Norte.

Lanuza said that Sunday’s magnitude-4.5 earthquake hit at 9:17 a.m. with its epicenter at six kilometers northwest of Carmen town in North Cotabato at a depth of 3 kilometers.

The earthquake was felt at Intensity 4 at the epicenter; Intensity 3 in the towns of Kabacan and Midsayap of North Cotabato; Intensity 2 in Pikit town; and intensity 1 in Kidapawan City.

At around 9:40 a.m., a weaker tremor, measured at magnitude 3.3 with its epicenter at eight kilometers northeast of Carmen, North Cotabato and a depth of 7 kilometers, again shook the province. It was felt at Intensity 2 on the areas near the epicenter.

By 10:04 a.m., another magnitude 3.3 quake jolted the province, its epicenter at 9 kilometers northwest of Carmen town with a depth of 4 kilometers. The earthquake was felt at Intensity 3 in Carmen, North Cotabato.

Magnitude is the measurement of the energy released at the source of the earthquake while intensity quantifies the strength of shaking produced by the tremor.

Intensity 1 means people hardly feel the shaking. Intensity 2 means a few people might feel the shaking if they are at rest or on the upper floors of a building. Intensity 3 means many people feel the shaking indoors and hanging objects will swing but people outdoors might not feel the shaking. Intensity 4 means most of the people indoors feel the shaking; hanging objects swing, dishes and objects would rattle. The earthquake may feel like a truck hitting a wall. A few people outside may feel the shaking and parked cars may rock. Intensity 5 means almost everyone feels the shaking and the earthquake may even awaken sleeping people. At Intensity 6, everyone feels the movement and in some cases, people may have difficulty moving.