Interseismic, Coseismic, and Early Postseismic Slip Associated With the 2025 Mw 8.8 Kamchatka Earthquake

Abstract Unraveling the surface deformation and fault kinematics during the seismic cycle is crucial for understanding earthquake physics. Herein, we use geodetic and seismic observations to quantify the interseismic coupling, coseismic rupture, and postseismic afterslip associated with the 2025 Mw 8.8 Kamchatka earthquake. We find that the rupture propagates southwest at 1.9–2.3 km/s, and the high‐frequency radiation shows a complementary pattern with the coseismic asperity. The coseismic slip and afterslip partially overlap and spatially coincide with strongly coupled patches, while the average coseismic slip significantly exceeds the interseismic accumulated slip deficit, indicating dynamic overshoot. Stress transfer analysis suggests that there exists a cascading triggering between foreshock, mainshock, and aftershock. Moreover, the coseismic and postseismic slip induced extensional strains at nearby volcanoes, potentially facilitating magma ascent. These findings improve our knowledge of the interplay among interseismic, coseismic, and postseismic slip, with implications for seismic and volcanic hazard assessment.