Tsunami Warnings Issued after Magnitude-8.7 Earthquake Strikes off Russian Coast
By Andrea Thompson, edited by Jeanna Bryner
Tsunami warnings and advisories have been issued around the Pacific Ocean following a powerful magnitude-8.7 earthquake that struck off the coast of Russia’s Kamchatka Peninsula. This earthquake is considered one of the largest globally, potentially ranking as the eighth largest on record. The last seismic event of this magnitude occurred in 2011 off the coast of Japan, resulting in a devastating tsunami that claimed thousands of lives and caused significant damage, including the Fukushima Daiichi nuclear power plant disaster.
The earthquake, which occurred in the late morning local time on July 30, has prompted evacuations in Japan and Hawaii. The U.S. Tsunami Warning System has issued alerts for Hawaii and the Aleutian Islands, with advisories in place for the rest of the Alaska coastline and the U.S. Pacific Coast. The initial waves began to make landfall around 10 a.m. local time, several hours after the earthquake struck.
The epicenter of the earthquake is situated in a subduction zone at the Kuril-Kamchatka Arc, where the Pacific plate is being subducted beneath the Okhotsk plate. This location is just 45 kilometers southeast of where a magnitude-9.0 earthquake occurred in 1952, resulting in a destructive tsunami that affected regions across the Pacific.
Interestingly, a magnitude-7.4 earthquake that occurred in the same region on July 20, 2025, is now considered a foreshock to the recent July 30 quake, according to the U.S. Geological Survey.
As scientists continue to monitor the situation and assess the potential risks of aftershocks and additional tsunamis, it is crucial for residents in the affected areas to remain vigilant and follow evacuation orders and safety protocols. The impact of this earthquake serves as a stark reminder of the power of nature and the importance of preparedness in the face of such catastrophic events.
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