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The 2021 Mw7.3 Maduo (Qinghai, China) earthquake ruptured ∼160 km along a poorly known secondary fault inside the Bayanhar block on the northern Tibetan plateau, which is generally parallel to the Kunlun fault. Here we integrate the interseismic (2015–2020) and coseismic geodetic observations to quantify the interseismic strain rate, fault geometry and coseismic slip distribution. Our results reveal that the seismogenic fault is featured by the low (<20 nanostrain/yr) and nearly undetectable interseismic strain rate. Three‐dimensional displacement fields and coseismic strain maps demonstrate the spatial variations of rupture kinematics due to the change of fault geometry. Our study reveals the steeply north‐dipping fault geometry of the seismogenic fault. The majority of coseismic slip occurred between 0 and 15 km with slight shallow slip deficit, which not penetrates through the inferred elastic upper crust (∼20–25 km). Our study highlights the tectonic and geometric control on fault kinematics of the Maduo earthquake. Plain Language Summary: The Bayanhar block on the north‐central Tibetan plateau experienced several major earthquakes with Mw > 6.5 on the boundary faults since the 1997 Mw7.6 Manyi earthquake, which is consistent with fast long‐term slip rates and large locking depth. However, the potential of generating large earthquakes on the faults inside the Bayanhar block is typically considered to be insignificant due to the estimated low fault slip rate (<5 mm/yr) and limited fault length. The 2021 Mw7.3 Maduo earthquake occurred on a poorly known subsidiary fault inside the Bayanhar block. Here, we use InSAR measurements prior to (2015–2020) and during the earthquake to investigate interseismic strain accumulation, to map coseismic deformation and to constrain the fault geometry as well as coseismic slip distribution of the Maduo earthquake. The three‐dimensional displacement fields and the relocated aftershocks support a slightly off vertical, dipping to the north, fault geometry. Our inversion results show that the coseismic slip is mainly distributed at a depth of 0–15 km. The kinematic analysis of the Maduo earthquake demonstrates that long‐term quantification of earthquake hazard of the subsidiary strike‐slip fault inside the Bayanhar block is challenging, because the interseismic strain rate is remarkably low and is largely undetectable by the geodetic observations. Key Points: Interseismic strain rate, coseismic three‐dimensional displacement field, finite strain and short‐term postseismic deformation of the Maduo earthquakeThe 2021 Maduo earthquake occurred on a subsidiary fault with a low (<20 nanostrain/yr) interseismic shear strain rateLong (∼160 km) rupture of the Maduo earthquake features shallow slip deficit with multi‐segment slip not penetrating through the upper crust [ABSTRACT FROM AUTHOR]

The 2019 Ridgecrest, California earthquake sequence ruptured along a complex fault system and triggered seismic and aseismic slips on intersecting faults. To characterize the surface rupture kinematics and fault slip distribution, we used optical images and Interferometric Synthetic Aperture Radar (InSAR) observations to reconstruct the displacement caused by the earthquake sequence. We further calculated curl and divergence from the north-south and east-west components, to effectively identify the surface rupture traces. The results show that the major seismogenic fault had a length of ~55 km and strike of 320 ° and consisted of five secondary faults. On the basis of the determined multiple-fault geometries, we inverted the coseismic slip distributions by InSAR measurements, which indicates that the Mw7.1 mainshock was dominated by the right-lateral strike-slip (maximum strike-slip of ~5.8 m at the depth of ~7.5 km), with a small dip-slip component (peaking at ~1.8 m) on an east-dipping fault. The Mw6.4 foreshock was dominated by the left-lateral strike-slip on a north-dipping fault. These earthquakes triggered obvious aseismic creep along the Garlock fault (117.3° W–117.5° W). These results are consistent with the rupture process of the earthquake sequence, which featured a complicated cascading rupture rather than a single continuous rupture front propagating along multiple faults. [ABSTRACT FROM AUTHOR]