Source of 6.9-quake traced

Local

PHILIPPINE scientists have identified the newly named Bogo Bay Fault as the source of the magnitude 6.9 earthquake that struck offshore northern Cebu on Sept. 30, 2025.

The Philippine Institute of Volcanology and Seismology (Phivolcs) confirmed on Friday, Oct. 3, that the fault’s onland extension lies in Sitio Looc, Barangay Nailon, Bogo City, where their Quick Response Team observed fault scarps, open cracks, and small pressure mounds within a two-meter-wide deformation zone.

“Initial field mapping recorded about 200 meters of surface rupture, while drone surveys revealed the fault may extend up to 1.5 kilometers, showing signs of right-lateral movement,” Phivolcs said in a social media post.

The agency added that field verification is ongoing to determine the full extent of the rupture.

Northern Cebu has experienced a total of 5,528 aftershocks following the magnitude 6.9 earthquake, authorities reported as of 12:00 PM on Saturday, Oct. 4.

Data from Phivolcs shows that 1,023 of these tremors were captured by instruments at the Medellin Earthquake Monitoring and Control Station, while 22 were strong enough to be felt by residents, with magnitudes ranging from 1.0 to 5.1.

Officials urged residents to brace for strong aftershocks, secure their homes, avoid unsafe structures, and rely only on official advisories.

The earthquake has caused widespread devastation in northern Cebu. The Cebu provincial government reported on Oct. 2 that damage in the province’s fourth district alone has reached P3 billion.

Cebu Public Information Officer Ainjeliz “AJ” Orong said the figure represents infrastructure damage across Bogo City and the municipalities of Bantayan, Daanbantayan, Madridejos, Medellin, San Remigio, Santa Fe, Tabogon, and Tabuelan.

She clarified that the estimate includes roads, buildings, and ports but does not yet account for other quake-hit towns such as Sogod and Borbon.

Department of Public Works and Highways Secretary Vince Dizon has ordered urgent inspections of schools and hospitals to ensure classrooms can safely serve as evacuation centers.

Patients from Cebu Provincial Hospital in Bogo City have been transferred to other facilities as a precaution. Dizon also instructed DPWH Central Visayas to deploy contractors from Cebu and nearby provinces to accelerate rehabilitation work.

Relief operations continue in tandem with infrastructure inspections.

Social Welfare Secretary Rex Gatchalian confirmed that food packs and assistance have reached northern Cebu, while Defense Secretary Gilbert “Gibo” Teodoro, who surveyed affected towns, highlighted food, potable water, and power restoration as immediate needs.

Capitol Command Center head Atty. Resti Arnaiz assured residents that relief distribution is ongoing in various towns, not only in Bogo City, and apologized to families who had not yet received aid, citing coordination delays with some local governments.

The magnitude 6.9 earthquake has displaced over 5,200 individuals, many of whom continue to sleep in tents or on roads due to the ongoing threat of aftershocks, including strong tremors reaching magnitude 5.1.

“The public is reminded to still be prepared for strong aftershocks and to get information from authorities and verified sources,” Phivolcs added.(MyTVCebu)