InSAR deformation observation and seismogenic tectonic analysis of the 2025 M_W6.0 Afghanistan earthquake

An M_W6.0 earthquake struck eastern Afghanistan on August 31, 2025, causing significant casualties. We utilized Sentinel-1 SAR images to derive a detailed co-seismic deformation field and inverted for source-fault parameters using an elastic half-space dislocation model. The results indicate that the seismogenic fault is a blind reverse fault striking NEE (approximately 49°), dipping at about 64°, with a maximum slip of approximately 1.2 m and a moment magnitude of M_W6.1. Calculations of Coulomb stress changes reveal that the earthquake loaded stress exceeding 0.01 MPa onto a local segment of the Kunar fault southwestern of the epicenter, while longer segments of the fault show stress unloading exceeding 0.01 MPa. Integrated tectonic analysis indicates that the seismogenic fault likely represents a blind thrust structure developed within a compressional zone associated with a conjugate strike-slip fault system, which, together with the Kunar fault, forms a local pop-up structure. The severe disaster caused by the earthquake is closely related to the shallow source, large slip, rock mass fragmentation, and high social vulnerability. This study reveals the rupture characteristics and tectonic mechanism of the earthquake from a space geodesy perspective, providing a basis for regional seismic hazard assessment.