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Interferometric synthetic aperture radar and teleseismic P‐wave data were combined to investigate the source rupture characteristics of the 2020 Mw 6.3 Yutian, China, earthquake. We first utilized the near‐field displacements together with 29 broadband teleseismic P waveforms to investigate the uniform slip model by using a Bayesian bootstrap optimization nonlinear inversion method to resolve the nucleation point location, origin time and fault geometrical parameters. Based on these results, the kinematic rupture process of the earthquake was inverted. We conclude that the 2020 Yutian earthquake occurred on a west‐dipping blind normal fault with a dip of ∼60° at the junction of Bayan Har block (BHB) and western Kunlun block (WKB). The rupture nucleation point was located at longitude = 82.435°E, latitude = 35.619°N, and a depth of 6.377 km, making it shallower than estimated from other point source inversions. The earthquake started at 21:05:20 UTC on June 25, 2020 and was delayed by ∼2.07 s compared with GeoForschungsZentrum. The rupture lasted for ∼12 s, with a total seismic moment of ∼3.28 × 1018 Nm, corresponding to a moment magnitude of 6.3. The slip was mainly confined between ∼3.0 and 9.0 km in depth and the peak slip was ∼1.40 m, which occurred at a depth of ∼6.377 km. The slip was predominantly normal slip with slight right‐lateral strike‐slip components, which agrees with the southeastward movement of the BHB relative to the WKB. Plain Language Summary: The June 25, 2020 Mw 6.3 Yutian earthquake occurred on a normal fault within the northwestern Tibetan Plateau, a region characterized by EW extension. Because the rough focal mechanism solutions and source locations based on seismic wave data reported by several institutes are different, they cannot be used to create a reliable fault model for inverting the kinematic rupture process of this moderate earthquake. The initial rupture point and origin time, which are the prior information needed for revealing the slip characteristics, are also unclear. To resolve these rupture parameters, both Sentinel‐1 interferometric synthetic aperture radar and teleseismic P‐wave data were collected. We found that the rupture mainly occurred in the shallow part of a ∼60° west‐dipping normal fault, the nucleation point was near the point of maximum slip, and the slip lasted ∼12 s and extended northward and southward. Our research has important significance for understanding earthquake disasters and deformation mechanisms of faults within the northwestern Tibetan Plateau. Key Points: Both interferometric synthetic aperture radar and teleseismic P wave are used to resolving the ambiguity of fault geometryThe rupture nucleation point and origin time were clarified by a Bayesian bootstrap optimization inversion methodRupture process of this earthquake is predominantly normal‐sip with slight right‐lateral strike‐slip components [ABSTRACT FROM AUTHOR]

Geodetic observations and seismic inversions suggest that the 2021 Mw7.4 Maduo earthquake's rupture velocity differs in two directions. However, the dynamic mechanisms underlying these differences remain unclear. To address this issue, we constructed a three-dimensional finite element model implementing heterogeneous fault geometry and real topography and simulated the Maduo earthquake's dynamic rupture process, with the tectonic stress field varying with depth. The results show that the uneven distribution of normal and shear stresses on the fault plane, due to the complex geometry of the seismogenic fault, is the primary factor controlling rupture velocity and slips on the fault plane of the Maduo earthquake. The modelled results reproduced basic kinematic characteristics as indicated by the observation and inversion results of the Maduo earthquake. Our study also suggests that if an earthquake occurs in a region without significant changes in velocity structure and stress field distribution, the complex geometry of the seismogenic fault is responsible for the dynamic rupture process. These findings provide important insights into the rupture behaviour of geometrically complex faults and have important implications for seismic hazard assessments of these complicated fault systems. • The dynamics rupture process of the 2021 Maduo earthquake was modelled. • The modelled results reproduced the rupture process indicated by the geodetic observations and seismic inversions. • Stress heterogeneity due to the complex fault geometry is responsible for the asymmetric and uneven rupture process. [ABSTRACT FROM AUTHOR]