A magnitude 7.1 earthquake struck off the coast of Malaysia on Sunday, sending tremors across parts of the country and neighboring regions. The U.S. Geological Survey (USGS) reported the quake occurred shortly before 5 p.m. GMT, or early morning local time, with an epicenter located 55 kilometers (34 miles) north-northwest of Kota Belud, in the Malaysian state of Sabah.
The earthquake, which occurred at a depth of 620 kilometers, was felt in Malaysia, the Philippines, and Brunei, triggering panic among residents, according to reports. Despite the significant magnitude, no tsunami warning was issued, and initial reports indicate no immediate reports of damage. The depth of the quake is notable; at 620 kilometers, it is considered a deep-focus earthquake, which typically causes less surface damage than shallower quakes of similar magnitude.
The USGS data places the timing of the event at 11:57 a.m. Eastern Time on Sunday, February 22nd. Shake intensity maps released by the New York Times, based on USGS data, indicate “light” shaking in the immediate vicinity of the epicenter, though the earthquake may have been felt over a wider area. The maps show areas experiencing a shake intensity of 4 or greater, as defined by the USGS.
Seismologists are continuing to analyze data from the event and may revise the reported magnitude as more information becomes available. Updates to the shake-severity map are also expected as additional data is collected. As of Sunday evening, February 22nd, aftershock data was being compiled, focusing on earthquakes within 100 miles and seven days of the initial quake.
The earthquake has prompted discussion among experts regarding a period of relative seismic quiet globally. Some seismologists suggest that this event may signal the end of a 76-day period without a magnitude 7.0 or greater earthquake, a period considered unusually long. One expert noted the possibility that this quake could be a precursor to a larger event, potentially a magnitude 8 earthquake, though this remains speculative.
The quake’s impact was felt in the Philippines, where residents reported feeling the tremors. While the extent of the impact in the Philippines remains unclear, the proximity of the epicenter to both Malaysian Borneo and the Philippines meant that the shaking was widely felt. Brunei also reported experiencing tremors.
The South China Sea is a seismically active region, though large earthquakes are relatively infrequent. The region’s complex tectonic setting, influenced by the subduction of the Eurasian Plate under the Philippine Sea Plate, contributes to this activity. Deep-focus earthquakes, like the one that struck on Sunday, are common in subduction zones.
While the immediate aftermath appears to have been relatively benign, with no reported tsunami and limited initial reports of damage, authorities in Malaysia and neighboring countries are likely to remain vigilant for potential aftershocks and to assess any structural damage that may have occurred. The depth of the earthquake, while mitigating surface damage, does not eliminate the possibility of localized impacts, particularly in areas with vulnerable infrastructure.
The USGS continues to monitor the situation and provide updates as they become available. The agency’s website remains the primary source for detailed information about the earthquake, including its magnitude, location, depth, and aftershock activity. The event serves as a reminder of the seismic risks present in the region and the importance of preparedness measures.
The earthquake occurred just days after a magnitude 6.1 earthquake was reported in Alaska, further highlighting the ongoing seismic activity around the Pacific Ring of Fire. While the two events are geographically distinct, they underscore the planet’s dynamic geological processes.