The 2025 Mw 8.8 Kamchatka Megathrust: A Rapid Recurrence With Complex Heterogeneous Rupture

Abstract On 29 July 2025, a Mw 8.8 earthquake struck Kamchatka, ∼50 km from the 1952 Mw 9.0 megathrust hypocenter, exhibiting a comparable aftershock zone. We resolve the kinematic rupture process and slip distribution by combining teleseismic waveforms with high‐quality tsunami data. The main slip is concentrated in the southwestern segment within moderate to deeper depths, closely corresponding to areas that experienced few earthquakes over the past 73 years. In contrast, the 1952 event suggests a shallow, near‐trench rupture. The peak slip (∼14 m) exceeds the accumulated slip deficit since the 1952 event (∼6 m), implying the 2025 earthquake did not merely re‐rupture the 1952 zone, but released stress on a deeper patch that likely remained locked during the 1952 event. Our findings suggest a potential depth‐dependent cycle mode where the shallow and deeper domains can be activated on different sub‐cycles and partially complement each other to accommodate long‐term plate convergence.