Massive Magnitude 7.4 Earthquake Strikes Off Kamchatka Coast, Tsunami warning issued

The tremor, initially measured at 7.5 before being revised downward, prompted the Pacific Tsunami Warning Center (PTWC) to issue a “hazardous” wave advisory for coastlines within 300 km of the epicenter, though the threat was lifted within hours.

Seismologists confirm this event as a major aftershock of the magnitude 8.8 earthquake that devastated the Kamchatka Peninsula on July 29, 2025, one of the strongest quakes recorded since 2011. That mainshock triggered tsunamis up to four meters high across the Pacific, prompting evacuations in Japan and Hawaii.

The September 13 aftershock resulted from shallow reverse faulting along the Kuril-Kamchatka subduction zone, where the Pacific Plate subducts beneath the North American Plate at about 80 mm per year. Despite its strength, no significant damage or casualties have been reported to date, and local authorities continue structural inspections in Petropavlovsk-Kamchatsky and surrounding areas.

Residents described panic and hurried evacuations from homes, airports, and public buildings, echoing scenes from the July catastrophe. Governor Vladimir Solodov urged calm and precaution, noting there were no immediate reports of severe damage or injuries.

As aftershocks continue, experts warn the region remains seismically active. Coastal communities are advised to stay alert for further advisories and to follow instructions from emergency services. The recent sequence of powerful earthquakes underscores the vulnerability of subduction zones and highlights the importance of robust early-warning systems in mitigating tsunami risks.