MAMBURAO, Philippines — A shallow magnitude-5.4 earthquake struck off Occidental Mindoro on Friday morning, shaking communities near the epicenter and swaying buildings across metropolitan Manila. By late Friday, however, authorities had reported no deaths, injuries or major structural damage.
The Occidental Mindoro Provincial Disaster Risk Reduction and Management Office said it had recorded no significant damage following its initial assessment. No quake-related closures or service interruptions involving roads, bridges, airports, ports, electricity or telecommunications had been announced.
The Philippine Institute of Volcanology and Seismology, or PHIVOLCS, said the tectonic earthquake occurred at 10:38 a.m. on Aug. 7, approximately 13 kilometers southwest of Mamburao, the provincial capital. It had an estimated depth of 14 kilometers.
PHIVOLCS initially measured the earthquake at magnitude 5.8, placed its epicenter 21 kilometers southwest of Mamburao and estimated its depth at 10 kilometers. The agency later revised the event to a moment magnitude of 5.4 after receiving additional seismic data—a routine adjustment as readings from more monitoring stations become available. Its final bulletin said damaging effects were not expected, although aftershocks were possible.
Strong Shaking Across Mindoro
Intensity V, classified by PHIVOLCS as “strong,” was reported in Mamburao and in several Oriental Mindoro communities, including Calapan City, Naujan, Puerto Galera, San Teodoro and Victoria.
Intensity IV shaking was reported in Taal, Batangas, and in the Occidental Mindoro municipalities of Abra de Ilog and Sablayan. Intensity III tremors reached Quezon City, Batangas City, General Trias in Cavite and San Pedro in Laguna. Weaker shaking was reported in Parañaque and parts of Laguna and Quezon province.
PHIVOLCS instruments recorded Intensity V in Mamburao and Puerto Galera, and Intensity IV in Abra de Ilog, Looc and Sablayan. Instrumental Intensity III was registered in Quezon City, Batangas City, Calapan and Victoria.
Despite the strong shaking reported near the epicenter, the provincial disaster office said no major damage had been found. Local reporting also indicated that no casualties had been recorded. Authorities continued monitoring communities for less-visible structural problems that might emerge during inspections.
Precautionary Inspections and Evacuations
The earthquake was clearly felt in Metro Manila, where employees left several government buildings as a precaution. Workers at the Sandiganbayan, Supreme Court and other offices temporarily moved to open areas, while employees of the Quezon provincial capitol in Lucena City also evacuated.
Metro Manila’s principal rail systems briefly implemented safety procedures. MRT-3 personnel inspected stations and the rail system after the tremor was felt along the line, according to an official transport advisory. Operations were subsequently reported as normal, with no quake-related damage identified.
These measures were precautionary and did not indicate that the buildings or railway had sustained structural damage. No tsunami threat was announced.
Mindoro and Mindanao Earthquakes Unconnected
The Mindoro earthquake followed seismic activity near southern Mindanao on Aug. 5 and 6, but PHIVOLCS said the events were not part of one connected sequence.
The Mindanao tremors were associated with continuing seismic activity near offshore Sarangani, while Friday’s Mindoro earthquake originated from a separate tectonic source. Their occurrence on consecutive days did not mean that one event triggered the other, PHIVOLCS officials told ABS-CBN News.
Reports of casualties and extensive infrastructure damage from earlier destructive earthquakes in Mindanao therefore should not be attributed to Friday’s magnitude-5.4 Mindoro event.
PHIVOLCS advised residents to remain prepared for aftershocks, check buildings for cracks or other signs of damage and follow instructions from local disaster officials. As of the latest available assessments, the Mindoro earthquake had caused alarm and temporary evacuations but no confirmed casualties or serious infrastructure damage.
Source: PHIVOLCS