Russian Journal of Earth Sciences Russian Journal of Earth Sciences Russian Journal of Earth Sciences 1681-1208 106682 10.2205/2026es001122 zdocit KAMCHATKA EARTHQUAKE M 8.8 ON JULY 29, 2025 KAMCHATKA EARTHQUAKE M 8.8 ON JULY 29, 2025 KAMCHATKA EARTHQUAKE M 8.8 ON JULY 29, 2025 Source Parameters of Strong Kamchatka Earthquakes in 2025 (MW > 7.0) from Surface Wave Data Source Parameters of Strong Kamchatka Earthquakes in 2025 (MW > 7.0) from Surface Wave Data https://orcid.org/0000-0001-9793-1685 Филиппова Алена Игоревна Filippova Alena Igorevna aleirk@mail.ru https://orcid.org/0000-0001-8930-0883 Фомочкина Анастасия Сергеевна Fomochkina Anastasia Sergeevna Институт земного магнетизма, ионосферы и распространения радиоволн им. Н.В. Пушкова РАН Москва, Троицк Россия Pushkov Institute of Terrestrial Magnetism, Ionosphere and Radio Wave Propagation of RAS Moscow, Troitsk Russian Federation Институт теории прогноза землетрясений и математической геофизики РАН Россия Institute of Earthquake Prediction Theory and Mathematical Geophysics of RAS Russian Federation РГУ нефти и газа (НИУ) имени И.М. Губкина Москва Россия University of Oil and Gas «Gubkin University» Moscow Russian Federation Институт теории прогноза землетрясений и математической геофизики РАН Россия Institute of Earthquake Prediction Theory and Mathematical Geophysics of RAS Russian Federation 01 07 2026 01 07 2026 26 2 ES2012 02 02 2026 25 05 2026 https://rjes.ru/en/nauka/article/106682/view

We consider four strong earthquakes with MW > 7.0 that occurred in 2025 near the Kamchatka Peninsula: the foreshock on July 20, mainshock on July 29, and two aftershocks on September 13 and 18. Their source parameters are estimated from teleseismic surface wave records in instant point and finite-fault (elliptical dislocation with a finite duration) source approximations. In addition, rupture planes are identified based on seismological data. The obtained rupture lengths of the study seismic events are discussed in detail as they are characterized by good resolution. They are compared to USGS finite-fault models, distributions of aftershocks, and some existing scaling relations between subsurface rupture length and magnitude. The July 29, 2025 mainshock is also compared to the November 4, 1952 earthquake with MW = 8.8–9.0. Two scaling relations, providing the best fitting for earthquakes with MW ≥ 8.0, are selected based on the obtained results and USGS data.

We consider four strong earthquakes with MW > 7.0 that occurred in 2025 near the Kamchatka Peninsula: the foreshock on July 20, mainshock on July 29, and two aftershocks on September 13 and 18. Their source parameters are estimated from teleseismic surface wave records in instant point and finite-fault (elliptical dislocation with a finite duration) source approximations. In addition, rupture planes are identified based on seismological data. The obtained rupture lengths of the study seismic events are discussed in detail as they are characterized by good resolution. They are compared to USGS finite-fault models, distributions of aftershocks, and some existing scaling relations between subsurface rupture length and magnitude. The July 29, 2025 mainshock is also compared to the November 4, 1952 earthquake with MW = 8.8–9.0. Two scaling relations, providing the best fitting for earthquakes with MW ≥ 8.0, are selected based on the obtained results and USGS data.

 Seismic moment tensor finite-fault modeling rupture length surface waves Kamchatka megathrust earthquake Seismic moment tensor finite-fault modeling rupture length surface waves Kamchatka megathrust earthquake The study was carried out under the State Assignments of the affiliated organizations. The study was carried out under the State Assignments of the affiliated organizations.

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