‘Light’ earthquakes hit Cebu, Davao Occidental

Screengrab from the Phivolcs Earthquake Information Bulletin

CEBU CITY, Philippines — The provinces of Cebu and Davao Occidental experienced light ground movements on Sunday, September 1.

The Earthquake Information bulletin issued by the Philippine Institute of Volcanology and Seismology (Phivolcs) logged a magnitude 3.1 earthquake in Dalaguete town, south of Cebu, at 4: 07 p.m.

No damage is expected from the ground shaking that was tectonic in origin. A tectonic earthquake happens when thin plates in the earth’s crust collide.

The towns of Sarangani and Jose Abad Santos in Davao Occidental also felt three ground shakings throughout the day.

A magnitude 2.6 earthquake first hit Jose Abad Santos town at 9:02 a.m. and was felt at Intensity 1 in Davao City and parts of Misamis Oriental; Intensity 2 in Bislig City, Davao Oriental, and Mati City, Surigao del Sur; and Intensity 3 in the towns of Baganga and Manay in Davao Oriental and parts of Caraga.

At 7:49 p.m. another magnitude 4.6 earthquake hit that town and was felt at intensity 1 in General Santos City. Sarangani also felt a magnitude 4.6 tremor at past 2 p.m.

Magnitude is the scale used to describe the energy released at the source of the earthquake of the earthquake or the number used to describe the relative size of the earthquake while intensity is the strength of the shaking produced by the earthquake, according to the United States Geological Survey (USGS).

The Phivolcs intensity scale published in the Official Gazette said that intensities 1, 2 and 3 earthquakes belong to the weak bracket of ground tremor. Intensity 1 earthquakes are hardly felt while 2 earthquakes are mostly felt by individuals who are at rest indoors and this may induce swinging of hanging objects.

An intensity 3 earthquake is similar to the shaking brought by a light truck passing by while quakes felt at intensity 4, which belongs to the moderately strong category, is generally felt by people indoors. |dbs