InSAR-Derived Coseismic Slip Model of the 2024 Ali Mw 5.6 Earthquake and Its Role on Landscape Evolution

Objectives: This study aims to investigate the landscape evolution effects of the 2024 Mw 5.6 earthquake that occurred in Ritu County, Ali region, on the Tibetan Plateau using interferometric synthetic aperture radar (InSAR) observations. The research seeks to explore the geodynamic processes and the role of normal faulting earthquakes in the topographic development of the Tibetan Plateau. Methods: We utilized Sentinel-1 synthetic aperture radar data to capture the coseismic deformation field. Nonlinear and linear inversion methods were applied to determine the source location, geometric parameters, and finite fault slip distribution. The Okada model was used to calculate the three-dimensional coseismic deformation field, which was then compared with the local topography. Results: The inversion results revealed that the Ritu earthquake had a strike of 336°, a dip of 66° to the east, and a predominantly normal slip component with a minor right-lateral com ponent. The centroid of the slip distribution was located at an altitude of over 5 435 m, making it the highestaltitude normal faulting earthquake recorded by InSAR in the Tibetan Plateau interior over the past 20 years. The comparison between the coseismic deformation field and the local topography indicated that the subsidence was concentrated at the summit, flatten local topography by reducing the gradient, thereby limiting the continuous uplift of the Tibetan Plateau. Conclusions: The study concludes that the 2024 Ali earthquake, with its high epicentral elevation, played a significant role in restraining the further uplift of the Tibetan Plateau. The findings, to some extent, support the gravitational collapse theory of normal faulting earthquakes within the plateau and provide insights into the intrinsic mechanisms that prevent the Tibetan Plateau from continually uplifting. This research highlights the importance of high-altitude normal faulting earthquakes in shaping the landscape of the Tibetan Plateau.