Earthquake of Magnitude 6.6 Jolts Philippine Sea

Philippine Sea: An earthquake of magnitude 6.6 rattled the Philippine Sea on Saturday, a statement by the National Center for Seismology (NCS) said.

The earthquake occurred at a depth of 65km.

In a post on X, the NCS said, "EQ of M: 6.6, On: 27/12/2025 20:35:56 IST, Lat: 24.64 N, Long: 122.12 E, Depth: 65 Km, Location: Philippine Sea."

The Philippine Sea borders the Philippines to its east, but it's a vast part of the western Pacific Ocean, with its floor being the Philippine Sea Plate; while the Philippines has sovereign rights over its adjacent waters (the West Philippine Sea within the South China Sea), the broader Philippine Sea is a large oceanic basin shared with other nations like Japan and Taiwan.

The Philippines lies in the Pacific Ring of Fire, a tectonic belt of volcanic arcs and oceanic trenches in the Pacific Ocean.

John Dale B Dianala, assistant professor at the National Institute of Geological Sciences, the University of the Philippines in Diliman, told Al Jazeera that just by virtue of the geographic and geologic setting of the country, the Philippines is home to many onshore and offshore tectonic faults.

"The whole length of the Philippines, around 1,800km, is right along the boundary of two major tectonic plates - the Philippine Sea plate and Eurasian plate - part of the so-called Pacific Ring of Fire. These two plates, thousands of kilometres wide, have been pushing against each other for millions of years at two to three times the rate of fingernail growth," he said.

"Each earthquake is a manifestation of the periodic release of the stress along long fractures on these plates - what geologists call 'faults' - which rupture several metres of movement along a fault in large earthquakes," he further told Al Jazeera.

"When the displacement involves vertical uplift of the seafloor from an offshore fault, like in the Philippine Trench to the east of the country, the movement displaces the water column from the depths of the ocean that then propagate to the surface and coasts in the form of tsunamis. Strong shaking can also cause submarine landslides that can also trigger tsunamis," he added.