PHILIPPINES EARTHQUAKE RAISES SEABED BY 2 METRES, EXPOSING CORAL

A 7.8-magnitude earthquake off southern Mindanao in the Philippines killed at least 61 people and raised the seabed by as much as 2 metres, according to the country's environment department. At least 40 people remain missing following the quake, which struck on Monday. Residents reported the geological phenomenon of "coastal uplift" two days after the earthquake, with shorelines extending by up to 200 metres in some locations. The Philippine Institute of Volcanology and Seismology attributed the uplift to a shift in the Cotabato trench, which pushed upward parts of the coastlines in Sarangani and Davao Occidental provinces.

A team sent to the affected area found that long stretches of shoreline, coral reef and seagrass beds had been exposed by the seismic activity. The Cotabato trench, located as close as 50 kilometres off the coast of southern Mindanao, is a site of frequent seismic activity. Images released by the environment department's regional office showed large areas of exposed coral with dead fish and other aquatic life visible on the newly exposed seabed. The exposed corals and seagrass beds began dying alongside their resident organisms, including reef fishes, eels, clams and shells.

An official stated that the precise extent of the affected area could not yet be determined given the scale of survey required. Residents initially reported the seabed changes out of concern they might be poisoned by fumes from decaying marine life. The Cotabato trench recorded a swarm of thousands of mostly small earthquakes in January preceding this major seismic event.