A magnitude-5.7 quake hit the Surigao area in Mindanao before midnight Thursday, causing a power blackout in at least two towns and prompting the preemptive evacuation of residents in coastal areas.
The Philippine Institute of Volcanology and Seismology (Phivolcs) said damage and aftershocks were expected from the quake, which was recorded at 11:11 p.m. and was tectonic in origin.
It said the quake’s epicenter was 54 km southeast of Surigao City.
Phivolcs said the quake was felt at:
* Intensity VI: Carrascal, Surigao del Sur; Cantilan, Surigao Del Sur;
* Intensity V: Claver, Surigao del Norte;
* Intensity III: Butuan City; Buenavista, Agusan del Sur; Socorro and Mainit, Surigao del Norte;
* Intensity II: Surigao City; Bislig City; and
* Intensity I: Cagayan De Oro City
An Intensity VI quake is considered “very strong,” Phivolcs said.
"Many people are frightened; many run outdoors. Some people lose their balance. motorists feel like driving on flat tires. Heavy objects or furniture move or may be shifted. Small church bells may ring. Wall plaster may crack. Very old or poorly built houses and man-made structures are slightly damaged though well-built structures are not affected. Limited rockfalls and rolling boulders occur in hilly to mountainous areas and escarpments. Trees are noticeably shaken," it said.
In an Intensity V quake described as strong, Phivolcs said, “Many sleeping people are awakened. Some are frightened, some run outdoors. Strong shaking and rocking felt throughout building. Hanging objects swing violently. Dining utensils clatter and clink; some are broken. Small, light and unstable objects may fall or overturn. Liquids spill from filled open containers. Standing vehicles rock noticeably. Shaking of leaves and twigs of trees are noticeable.”
An Intensity III quake is defined as “weak,” an Intensity II quake “slightly felt,” and an Intensity I quake “scarcely perceptible.”
Meanwhile, Phivolcs said at least two predawn quakes hit the Mindanao area after midnight Thursday.
At 12:03 a.m., a magnitude-3.4 quake occurred 10 km northwest of Carrascal, Surigao del Sur.
At 12:54 a.m., a magnitude-3.7 quake hit at 10 km northeast of Jabonga, Agusan del Norte. Aftershocks were expected.
Power failure, evacuation
Last night’s magnitude-5.7 quake caused a power failure and prompted preemptive evacuation in coastal areas there.
The National Disaster Risk Reduction and Management Council (NDRRMC) said Friday Cantilan and Carrscal towns in Surigao del Sur experienced a total blackout after the quake.
"However, power resumed at around 1:30 a.m. Friday," it said.
The NDRRMC also said Carrascal town disaster management officials conducted a preemptive evacuation of coastal areas, “for fear of a tsunami occurrence.”
For its part, Cantilan town’s disaster management officials alerted local residents “to be on alert if a call for evacuation is needed.”
A separate report on dzBB radio quoted Phivolcs seismologists as saying the quake damaged some houses.
Philippine National Red Cross Surigao del Sur chapter administrator Adel de Guzman said they are checking local highways for possible damage.
2 more quakes
At least two more quakes hit Mindanao Thursday night before the magnitude-5.7 quake occurred.
The first measuring magnitude 5.6 occurred at 8:52 p.m., with the epicenter at 240 km southeast of General Santos City.
It was felt at:
Intensity III: Compostela Valley; Malita, Davao del Sur;
Intensity II: Davao City; and
Intensity I: General Santos City.
At 10:27 p.m., a magnitude-3.3 quake hit at 12 km northeast of Carrascal, Surigao del Sur.
Also, an earlier report said at least three quakes hit Mindanao last Thursday evening in an hour.