A 7.8 magnitude earthquake that struck off the southern Philippines island of Mindanao on 8/6 has caused the seabed to rise by approximately 2 meters, exposing vast coral reefs and damaging the marine ecosystem. The Philippine Institute of Volcanology and Seismology (PHIVOLCS) announced on 14/6 that the movement of the Cotabato Trench, located about 50 kilometers off Mindanao's coast, lifted parts of the coastlines in Sarangani and Davao provinces. This uplift revealed previously submerged sections of the seabed, which PHIVOLCS estimated at about 2 meters.

The Cotabato Trench is an area known for frequent seismic activity, including a series of thousands of earthquakes, mostly minor, recorded in January.

Coral reefs exposed above water after the 7.8 magnitude earthquake in the Philippines, in an image released on 14/6. Photo: Philippine Department of Environment

A survey team dispatched to the site reported discovering extensive areas of seabed and coral reefs completely exposed above the water. In some locations, the coastline is believed to have expanded by approximately 200 meters.

An official stated that the exact extent of the affected area cannot yet be determined due to the vast size requiring surveying. Images released by the regional office of the Philippine Department of Environment show large coral bands exposed, alongside numerous dead fish and marine organisms scattered across the surface.

"The exposed underwater ecosystem has begun to die, affecting living organisms such as reef fish, sea eels, clams, and other shelled mollusks", the department reported.

Dead fish after coral reefs emerged above the water. Photo: ASEAN Today

The 7.8 magnitude earthquake, which occurred off the southern Philippines island of Mindanao on 8/6, has resulted in at least 61 fatalities. According to updated figures from the disaster response agency, at least 40 people remain missing.

Local residents first observed the seabed uplift two days after the earthquake.

The Philippines is among the nations with complex geological structures situated on the "Pacific Ring of Fire", a zone of seismic activity extending from South America to Russia's Far East. Earthquakes occur almost daily in the country.

By Huyen Le (According to AFP, Guardian)