Preliminary slip distribution of the July 29, 2025 M_W 8.8 Kamchatka, Russia earthquake

Abstract

The M_W 8.8 Kamchatka earthquake in Russia's Kamchatka Peninsula is one of the top ten largest earthquakes worldwide since 1900. This event occurred in a tectonically active Kurile–Kamchatka subduction zone where several large earthquakes (M > 8) have occurred over the past 100 years. Here, we combine the teleseismic vertical-component P-wave back-projection method and finite fault inversion with teleseismic P and SH waveforms to investigate the kinematic features of this earthquake. The results indicate that the ruptured area spans approximately 600 km in length and 175 km in width, with a total source duration of about 220 s. Moreover, the coseismic slip occurred mainly within the subducting interface away from the trench, reaching a maximum slip of about 8 m. Notably, the rupture propagated approximately 500 km southwestward from the hypocenter, consistent with the aftershock distribution. These results imply that the rupture zone of this earthquake might spatially overlap with that of the 1952 M_W 8.8–9.0 Kamchatka earthquake. Furthermore, the smaller than anticipated tsunami generated by this megathrust event could be attributed to its limited shallow slip near the trench. This study provides preliminary kinematic insights into this event and lays a certain foundation for subsequent in-depth studies.

Keywords

Rupture process / Coseismic slip / Kamchatka earthquake / Aftershock location / Subduction zone

CRediT authorship contribution statement

Duyuan Xu: Conceptualization, Data curation, Formal analysis, Funding acquisition, Investigation, Methodology, Validation, Visualization, Writing – original draft, Writing – review & editing. Weimin Wang: Conceptualization, Formal analysis, Investigation, Methodology, Software, Visualization, Writing – review & editing. Zhikun Ren: Conceptualization, Formal analysis, Writing – review & editing.

Declaration of competing interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. The author Zhikun Ren is the associate editor of this journal and declares that he is not involved in the review process.

Author agreement and acknowledgement

We thank the editor Baoshan Wang and the three anonymous reviewers for their detailed and insightful reviews. This work was funded by the Major Program of the National Natural Science Foundation of China (42494864). We thank Prof. Zhigang Peng for his helpful comments and discussions.

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