September 18, 2025
2 min read
Strong Earthquake Hits Kamchatka. Tsunami Risk Waning
A powerful magnitude 7.8 aftershock off Russia’s Kamchatka Peninsula that arose from July’s magnitude 8.8 earthquake is raising concerns about possible tsunami impacts, although risk appears to be waning
A seismic map shows the epicenter and intensity of a major earthquake that struck off the eastern coast of Russia’s Kamchatka Peninsula on September 18, 2025, EDT.
Less than two months after a magnitude 8.8 earthquake rocked Russia’s Kamchatka Peninsula, another strong earthquake occurred early on September 19 local time.
Although tsunami waves have been observed closer to the earthquake’s epicenter off Kamchatka’s eastern coast, shortly before 5 P.M. EDT, officials at the Pacific Tsunami Warning Center announced an “all clear” for Hawaii, ruling out the possibility of giant waves crossing the Pacific Ocean.
The U.S. Geological Survey made an initial estimate of the new earthquake’s magnitude as 7.8, meaning that the July 29 event released more than 30 times the energy of this one and produced waves with about 10 times the magnitude of the latter. (The scale by which scientists measure earthquakes is logarithmic, not linear.)
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The July event was among the 10 strongest earthquakes on record; this new temblor won’t make that cut. According to Reuters, the Kamchatka region’s governor said that there have been no reports of damage from the recent event in the sparsely populated region.
USGS has already confirmed that the magnitude 7.8 event is an aftershock of the earlier earthquake, making it the latter quake’s largest aftershock to date. Both earthquakes occurred on the Kuril-Kamchatka plate boundary, which stretches from northern Japan, along the eastern coast of the Kamchatka Peninsula, toward the Aleutian Islands. Here, the Pacific plate is sinking under the North American plate, making the region one of the world’s most seismically active, according to USGS.
The July earthquake spurred concerns of a serious tsunami but ended up not producing such a phenomenon because of local geology.
If you live in Hawaii or along the western coast of the U.S. when a tsunami risk is declared, monitor tsunami alerts from the federal government and follow the directives of local emergency response personnel.
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