Temblors traced to still shaken Batangas

(7th UPDATE) Multiple earthquakes jolted parts of Luzon on Saturday afternoon with the strongest one recorded at magnitude-6, registering an Intensity 7 (VII) in the town of Mabini in Batangas.

The Philippine Institute of Volcanology and Seismology (PHIVOLCS) measured the first earthquake at magnitude 5.6, with its epicenter 2 kms northwest of Mabini.

The temblor was felt around Metro Manila and other parts of Luzon, according to reports posted by the public on social media.

A second earthquake, measured at magnitude 6.0, followed 2 minutes after.

The magnitude-6 earthquake registered an Intensity VII in Mabini, while Intensity VI was recorded in Calatagan, Nasugbu and Tingloy in Batangas.

Intesity V was felt in Batangas City, Santo Tomas and Lemery in Batangas City and in Tagaytay City.

Intensity IV was felt in Dasmariñas, Cavite, Lucena City and Pateros City, while Intensity III was reported in Makati City, Pasay City, Quezon City, Muntinlupa City, Malabon City, Mandaluyong City and Bacoor Cavite.

The quake was also felt at Intensity II in Daet, Camarines Sur.

• Watch: Passengers rush to leave Batangas Port due to earthquake

Smaller quakes were subsequently felt in Batangas with magnitudes ranging from 3.1 to 4.7 in the succeeding hours.

The latest tremor was recorded at 6:18 p.m. and measured at magnitude-3.6 with the epicenter located 24 kilometers northwest of San Luis in Batangas.

In an interview with DZMM, PHIVOLCS director Renato Solidum said the series of earthquakes that hit Batangas was part of the normal movement of a fault line in the area.

• Read: Series of quakes 'normal', says PHIVOLCS chief

Solidum said the quakes, three recorded within half an hour in Batangas, may be considered an earthquake swarm and noted that
there was "nothing unusual" with such phenomenon, and was expected of a gradually moving fault line.

"Hindi po unusual 'yun. Pwede pong magkaroon ng ganyang earthquake swarms na mga ganyang lindol na posibleng magkakalapit ang magnitude pero hindi talaga major earthquake," he said.

"Normal po 'yan sa mga fault na kumikilos paunti-unti. Kasi kung biglaang kumikilos 'yung mga fault, malakihan po kaagad 'yung earthquake tapos 'yung mga sumusunod, maliliit," Solidum added.

USGS records 3 tremors

The United States Geological Survey (USGS), meanwhile, recorded 3 tremors with the third one recorded at magnitude-5.0 in Batangas Saturday afternoon, some 20 minutes after twin earthquakes hit the province.

The USGS said the third tremor struck at 3:29 p.m. Saturday 1 km west northwest of Taysan town, also in Batangas. The town is located east of Mabini, where two quakes a minute apart occurred less than half an hour earlier.

There is no information yet as of posting time whether the third quake was an aftershock.

The first earthquake hit 2 kms east-northeast of Bagalangit village at 3:08 p.m., with a magnitude of 5.7. A 5.9-magnitude temblor hit a minute later, 1 km south-southwest of Talaga in the same town, per the USGS.

The quake's origin is proximate to the island town of Tingloy, where a magnitude-5.5 quake hit just before 9 p.m. Tuesday. It generated multiple aftershocks.