On 30 July 2025, at 11:24:52 PETT (29 July, 23:24:52 UTC), a 8.8 megathrust earthquake struck off the eastern coast of the Kamchatka Peninsula in the Russian Far East, east-southeast of the coastal city of Petropavlovsk-Kamchatsky. It was the most powerful earthquake recorded worldwide since the 2011 Tōhoku earthquake, and is tied with the 1906 Ecuador–Colombia and 2010 Chile earthquakes as the sixth-strongest ever recorded by seismometers. However, it caused minimal damage compared to other earthquakes of similar magnitude. The earthquake caused moderate damage and multiple injuries in Kamchatka Krai and Sakhalin Oblast. The subsequent Pacific-wide tsunami was weaker than expected, with waves approximately or less in most places. However, a locally high run-up of was recorded in a steep narrow river valley near Vestnik Bay. One indirect fatality and 21 injuries were attributed to tsunami-related evacuations in Japan.
Tectonic setting
The earthquake occurred on the Kuril–Kamchatka subduction zone, a large thrust fault and convergent plate boundary between the Okhotsk plate and Pacific plate that extends from the east coast of the Kuril Islands to the Kamchatka Peninsula. Active subduction of the Pacific plate beneath the Okhotsk plate has been continuous since the Cretaceous. Estimates of the rate of convergence between these two plates varies between annually.Cui, Q., Zhou, Y., Liu, L., Gao, Y., Li, G., & Zhang, S. (2023). The topography of the 660-km discontinuity beneath the Kuril-Kamchatka: Implication for morphology and dynamics of the northwestern Pacific slab. Earth and Planetary Science Letters, 602, Article 117967.
Large earthquakes on the subduction zone have been recorded before. The previous largest was the 1952 Severo-Kurilsk earthquake which measured 8.8–9.0 and had an epicenter southeast of the 2025 earthquake. This event caused a large and destructive tsunami along the Kamchatka coast. It is believed to have ruptured a by section of the subduction zone from Shipunskii Cape in the north to Onekotan in the south. Unlike most large subduction earthquakes, the greatest fault movement in the 1952 event occurred at greater depth instead of being closer to the trench. Movement on the fault was inferred to be as deep as and possibly . Little slip occurred at the trench, leaving it locked and accumulating unreleased elastic energy.
A larger earthquake occurred in 1737 and had a magnitude estimated at 9.3. This earthquake generated a tsunami high according to written records by travellers and tsunami deposit observations. In 1841, another earthquake with an estimated magnitude of 9.0 produced a major tsunami that was also recorded in Hawaii.
In a paper from Izvestiya, Physics of the Solid Earth dated to 23 July 2025, researchers studied ring-shaped seismicity in southern Kamchatka, a pattern in earthquakes where their epicenters are distributed around an elliptical "ring" shape. These events are often associated with the preparatory process of a large earthquake on an active fault. An analysis of earthquakes from 1973 to late 2024 revealed three ring-shaped seismicity structures at , , and . Existing studies reported that a large earthquake usually occurs about 10 to 15 years after a sudden high rate of seismicity around these structures, and in the Kamchatka area, this occurred in 2016. The paper said there was a likelihood of a large earthquake occurring between 2026 and 2031 with a moment magnitude of 8.4–8.8.
Earthquake
The large submarine earthquake occurred on 29 July at 23:24:50 UTC with a moment magnitude () of 8.8, according to the United States Geological Survey (USGS). The International Seismological Centre (ISC) assigned the earthquake a moment magnitude of . Its epicenter was off the Pacific coast of the Kamchatka Peninsula, about east-southeast of Petropavlovsk-Kamchatsky, while the hypocenter was put at a shallow depth of . The National Institute of Geophysics and Volcanology and Geoscience Australia both put the magnitude at .
The USGS said the earthquake occurred as a result of shallow reverse faulting on the subduction zone interface. They estimated the area where movement occurred on the interface to be by . The rupture was believed to have re-ruptured the part of the fault that slipped in the Mw 9.0 1952 Severo-Kurilsk earthquake, and also filled any remaining seismic gap between the 1952 and 1923 Kamchatka earthquakes.
A foreshock, measuring , struck on 20 July, about to the southwest of the 29 July mainshock. The foreshock was preceded by smaller earthquakes in the hour before, including a earthquake. At least 4,003 aftershocks followed, with 28 equal to or greater than , including a event at 00:09 UTC on 30 July, a on 3 August, a on 13 September, and a on 18 September.
In Japan, the earthquake was felt at an intensity of 2 on the Shindo scale in Hokkaido.
Characteristics A finite fault model released by the USGS indicated slip on an approximately by segment of the Kuril–Kamchatka Trench up to a depth of . A majority of the rupture propagated along the subduction zone from the hypocenter to the southwest as far as Onekotan Island, while the remaining propagated northeast towards offshore Cape Shipunskii, albeit producing only negligible amounts of slip (less than ) in small patches close to the trench.
The model divided the fault into three segments based on the depth profile and dip angle. Segment 1 represented the part closest to the trench, extending in depth. Near the trench, slip values peaked at at depth while at depth, another area of high slip () was inferred.
This high slip zone extended into Segment 2 ( range), where of slip was recorded. About southwest, another zone of peak slip is inferred with the maximum dislocation estimated at . These two zones of high slip is separated by a narrow zone of smaller slip (~). The deepest portion of the rupture, represented by Segment 3, exhibited of slip at ~ depth. Most coseismic displacements occurred on Segments 1 and 2 in a region southwest from the hypocenter at depths of .
The GEOSCOPE Observatory estimated that the earthquake ruptured the subduction zone for a duration of more than 180 seconds. The USGS estimated the earthquake's duration to be about 270 seconds (four minutes and 30 seconds).
Geological effects An eruption occurred on 30 July at Klyuchevskaya Sopka, a volcano on the Kamchatka peninsula, shortly after the earthquake, although the eruption was not directly caused by the earthquake, and activity at the volcano had been observed over the preceding days. On 3 August, Krasheninnikov, another volcano, generated a eruption plume. It was the first recorded eruption on the volcano since human observations began. The Institute of Volcanology and Seismology of the Russian Academy of Sciences said on 6 August that seven Kamchatka volcanoes had erupted due to the earthquake, an occurrence that had not been seen on the Kamchatka Peninsula in nearly 300 years.
Parts of the southern Kamchatka Peninsula shifted southeast by as much as according to the Geophysical Service of the Russian Academy of Sciences.
Tsunami Warnings
Space NASA's GNSS-based Upper Atmospheric Realtime Disaster Information and Alert Network (GUARDIAN), comprising a portion of the Global Navigation Satellite System, had an AI component installed the day before the earthquake, which informed scientists in near real-time of the tsunami crossing open ocean. The vast column of water uplifted over a wide area pushed up the mass of air above it, sending ripples of low-frequency sound and gravity waves upwards into the ionosphere, thus measurably perturbing the orbits of GPS satellites.
Asia The Pacific Tsunami Warning Center (PTWC) warned of "hazardous tsunami waves" along the coasts of Russia and Japan. Authorities in Russia also issued tsunami warnings for the Kamchatka Peninsula and the Kuril Islands, which were cancelled on the evening of 30 July. On 3 August, a magnitude 7.0 aftershock off the Kuril Islands prompted Russian authorities to issue a tsunami warning in parts of Kamchatka, with the Ministry of Emergency Situations warning of waves of up to . The alert was lifted later that day.
In the first tsunami alerts issued in Japan since the 2024 Hualien earthquake, the Japan Meteorological Agency (JMA) issued a tsunami warning for the coasts of Hokkaido down to Wakayama Prefecture in Honshu. Tsunami advisories were issued for Shikoku down to the Okinawa Islands and elsewhere; 900,000 people in 133 municipalities were also advised to evacuate. The agency said up to waves were expected to reach the coast and urged the evacuation of the areas expected to be impacted. The runways of Sendai Airport were closed, while JR East, JR Central, and JR Hokkaido suspended rail services. Workers at the Fukushima Daiichi Nuclear Power Plant were ordered to evacuate, while a scheduled release of treated radioactive water from the facility into the Pacific Ocean was halted. The Japanese Defense Ministry deployed its air assets to the Pacific coast to gather information. Around two million people across the country were advised to evacuate. The JMA downgraded its warnings to advisories on the night of 30 July and lifted them altogether the next day.
Indonesia's Meteorology, Climatology, and Geophysical Agency issued a warning for parts of Papua, North Maluku, North Sulawesi, and Gorontalo. Authorities in Indonesia expected small tsunami waves of less than in coastal areas of the regions mentioned, advising residents to move away from beaches and low-lying shores.
In China, the Ministry of Natural Resources issued a yellow alert, the second lowest of a four-tier tsunami alert level system, covering Taiwan, Zhejiang Province, and Shanghai.
Taiwan's Central Weather Administration issued a "tsunami watch" alert, saying that waves as high as could hit the island's southeastern and southwestern coasts. The tsunami marked the first time the Central Emergency Operation Center was activated for such an event, causing 23 rescue aircraft and 14 naval vessels to be placed on standby.
The Philippine Institute of Volcanology and Seismology issued a tsunami advisory for the Pacific coast of the Philippines with waves expected to be up to . The advisory covered 22 provinces from Batanes to Davao Occidental. The advisory was eventually cancelled as the seismological agency did not record significant sea level disturbances and destructive tsunami waves.
The PTWC also warned of waves measuring less than hitting South Korea.
Oceania The PTWC warned that tsunami waves high were possible in Hawaii and the Solomon Islands, and that waves up to were likely to affect American Samoa, Chuuk, Kiribati, Nauru, New Caledonia, Niue, Papua New Guinea, the Pitcairn Islands, Tokelau, Tuvalu, Vanuatu, and Wallis and Futuna. Guam and Australia were also put under an advisory, and alerts were also issued in Palau and the Northern Mariana Islands.
The governor of Hawaii, Josh Green, said data from Midway Atoll measured waves from peak to trough of and noted that a wave of that size could dislodge trees and move cars. The size of the waves which would hit the state remained uncertain. Immediate evacuations were ordered for coastal areas across Hawaii, with the first waves expected to reach the state at roughly 19:00 HST (UTC–10). Hawaii later downgraded the warnings to an advisory.
An advisory was issued by the National Emergency Management Agency (NEMA) for "strong currents and unpredictable surges" around the entire coast of New Zealand; the next day, NEMA extended the advisory for another 24 hours due to rebounding tsunami activity from South America.