A powerful M7.4 earthquake occurred east of Petropavlovsk-Kamchatky, Kamchatka, Russia, at 06:49 UTC on July 20, 2025.
According to data provided by the United States Geological Survey (USGS), the mainshock was preceded by six foreshocks, the strongest of which was an M6.6 at 06:28 UTC, approximately 20 minutes before the main event.
Since the sequence began, the USGS has registered a total of 136 earthquakes of magnitude 4.0 or greater in the region through 09:00 UTC today. Of these, 40 had magnitudes above 5.0, and five exceeded magnitude 6.
The latest M6+ event, an M6.1, occurred at 01:59 UTC on July 22, followed by six aftershocks with magnitudes between 5.0 and 5.3.
According to the USGS, the M7.4 earthquake was the result of reverse faulting at a depth of about 20 km (12 miles). At this location, the Pacific plate moves west-northwest relative to the North America plate at a rate of approximately 77 mm (3 inches) per year.
The mechanism and epicentral position are consistent with motion along the subduction zone plate interface of the Kuril-Kamchatka Arc.
Events of this magnitude typically involve rupture over fault areas about 60 km by 35 km (37 miles by 22 miles). While earthquakes in this region are often plotted as points, their physical impact corresponds to slip across large segments of the plate boundary.
The Kuril-Kamchatka arc is characterized by frequent moderate-to-large earthquakes and has experienced 29 additional events of M6.5 or higher within 250 km (155 miles) of the July 20 epicenter over the past century.
The current sequence is located roughly 73 km (45 miles) northeast of the epicenter of the 1952 M9.0 Kamchatka earthquake, which generated a destructive Pacific-wide tsunami.
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