The Negros Trench, located off the western coast of Negros Island, is among the country’s active offshore trenches that could generate an earthquake as strong as magnitude 8.2, according to the Philippine Institute of Volcanology and Seismology (PHIVOLCS).
PHIVOLCS Director Teresito Bacolcol said the Negros Trench is one of six trenches being closely monitored by the agency. The others are the Philippine Trench, East Luzon Trough, Manila Trench, Sulu Trench, and Cotabato Trench.
Situated west of the Negros Island Region and northeast of the Sulu Trench, the Negros Trench stretches for about 400 kilometers along the seafloor. It forms part of the Sunda Plate boundary in the southwestern Pacific and is considered one of the major earthquake-generating structures affecting Central Philippines.
Bacolcol said these trenches are capable of producing powerful earthquakes similar to the magnitude 8.1 earthquake that struck Mindanao on Aug. 17, 1976. The quake triggered a tsunami that devastated coastal communities and remains one of the deadliest seismic events in Philippine history.
With Negros and neighboring islands situated near the trench, PHIVOLCS urged residents to prepare emergency go-bags, familiarize themselves with evacuation routes, and regularly monitor official advisories.
While scientists cannot predict exactly when a major earthquake will occur, the agency stressed that preparedness and awareness remain the best defenses against earthquake-related disasters.
The warning was issued days after the magnitude 7.8 earthquake that rocked Sarangani on June 8, prompting authorities to remind the public that several major earthquake sources remain active across the country.*
Reymund Titong is a Filipino journalist steadily building his voice in the field of news reporting, driven by a commitment to tell meaningful and relevant stories.
He serves as a correspondent for Rappler, contributes to Negros Daily Bulletin, and maintains a blog on Medium.