On 17 June 2019, an Ms6.0 earthquake occurred in Changning, Sichuan, China (Changning event), which was the largest earthquake on record within 50 km of the area. It attracted great attention as the area has the largest shale gas production in China as well as significant mineral salt production. Using the Interferometric Synthetic Aperture Radar (InSAR), we extract the coseismic deformation of the Changning event and two earlier Ms > 5.0 earthquakes which occurred in the same region (16 December 2018 Ms5.7 and 3 January 2019 Ms5.3) from the Sentinel-1 and ALOS2 data. We use nonlinear and linear methods to invert the fault models of the three earthquakes based on the deformation fields. The final model shows that the Changning event was caused by a fault with left-lateral strike and thrust slip. The strike is 124.3° with a dip angle of 43.4°. The seismic moment obtained by inversion is 5.28 × 10¹⁷ Nm, corresponding to Mw 5.78. Based on the fault models, we analyze the cause of the Changning earthquake considering the local tectonic setting, Coulomb stress change, mining, and fluid injection. We consider that the event may be related to salt mining. The two earlier Ms > 5.0 earthquakes may also play an important role in advancing the Changning earthquake.

On 8 September 2023, an Mw 6.8 earthquake struck the High Atlas Mountains in western Morocco, where the tectonic regime has been poorly investigated due to its remoteness and weaker seismicity compared to the northern plate boundary. In this study, we combine the measurements from the Interferometric Synthetic Aperture Radar images and the seismic data to invert the coseismic slip model of the 2023 Morocco earthquake. The results show a predominantly reverse slip motion with a minor left-lateral strike slip. The rupture process lasts about 15 s and reaches the maximum of its seismic moment release rate at about 5 s. The coseismic slip is mainly distributed in a depth range of ~20–30 km, with the ~1.4 m maximum coseismic slip at a depth of ~25 km. The Coulomb stress change suggests a significant stress loading effect on surrounding faults. The high-angle transpressive rupture kinematics of the 2023 Morocco earthquake reveal steep oblique–reverse faulting of the Tizi n’Test fault within the western High Atlas Mountains. The slight left-lateral strike slip and focal depth anomaly of this event are largely attributed to differential crustal shortening and the rejuvenation of early rift structures inherited from the Mesozoic complex evolution.

The 2024 Mw 7.0 Wushi and 2020 Mw 6.0 Jiashi earthquakes, two recent large events in the southern Tian Shan, provide rare opportunities for understanding the seismotectonic deformation patterns in compressional orogenic regimes. Here, we utilize Sentinel-1 satellite radar images and Differential Interferometric Synthetic Aperture Radar techniques to map coseismic deformation fields for the 2024 Wushi and 2020 Jiashi earthquakes, occurring at the front and root of the Kepingtage fold-and-thrust belt, respectively. A modified Bayesian nonlinear method is utilized to simultaneously invert fault geometry parameters and slip distributions. Our findings show that both Wushi and Jiashi earthquakes are predominantly characterized by reverse/thrust motions with minor strike-slip components. The spatial continuity of the interferometric fringes and coseismic deformation fields suggests shallow (<5 km depth) folding deformation in response to deeper reverse/thrust faulting. Specifically, the Wushi earthquake produced a high-angle fault-propagation fold, with fault-slip penetrating into the crystalline basement, whereas the Jiashi earthquake formed a low-angle detachment fold developed within the cover layer. The Mw 5.7 aftershock following the Wushi mainshock compensated for the shallow coseismic slip deficit and generated positive flowerlike ruptures superimposed on the pre-existing mainshock fold deformation, explaining the observed opposite dip direction of the aftershock rupture compared to the mainshock mechanism. These two fold-type earthquakes demonstrate the dominance of folding deformation in accommodating crustal shortening and orogenic growth in the southern Tian Shan, elucidating compressional tectonic processes.

On 4 December 2025, nearly two years after the 2024 Mw 7.0 Wushi earthquake, an Mw 5.8 event struck the nearby county of Aheqi, southwestern Tianshan. Owing to the subparallel strikes of both nodal planes and the interspersed hypocenter locations among regional structures in the reported focal mechanisms, the exact fault geometry of this event remains unresolved, impeding a better understanding of regional tectonic activity and the associated seismic hazards. To resolve this, we applied Interferometric Synthetic Aperture Radar (InSAR) technique to map the coseismic deformation and invert for the fault geometry and slip pattern. Significant tropospheric delays are mitigated using a moving-window linear model and a multi-interferogram weighted averaging strategy. The result shows significant uplift (~5.0 cm for ascending track and ~6.0 cm for descending track), indicating thrust-dominated mechanism. Bayesian inversion reveals two possible fault models: a 31.6° north-dipping blind thrust or a 54.4° south-dipping back-thrust. While both fault planes fit the InSAR observations, integrated evidence from the absence of back-thrust development conditions, the surface deformation pattern, and regional topography indicates that the north-dipping Aheqi fault is the causative structure. Together with the steeper Maidan fault to the north, it forms the Orogen Basin boundary along the southern Tianshan piedmont. Our findings highlight that resolving moderate blind-thrust seismogenic structures using InSAR requires integration with pre-existing structural and geomorphic evidence. Furthermore, Coulomb stress calculations indicate a rupture-promoting effect from the Wushi earthquake, which occurred on a reactivated fault, onto the Aheqi event, with stress loading exceeding 2 bar at the hypocenter. Thus, the potential for stress-driven sequential rupture between reactivated and present-day active structures necessitates an updated seismic hazard assessment in the southern Tianshan.

Knowledge of the regional crustal deformation and stress field is fundamental to understanding and constrain the ongoing Hovsgol basin evolution. The 2021 Mw 6.7 Turt earthquake provides an unprece...

On 23 January 2024, a magnitude (Mw) 7.0 earthquake struck Wushi County (China) in the southwestern Tian Shan orogen. Both Sentinel-1 and Advanced Land Observation Satellite-2 radar images were used to obtain coseismic displacements with interferometry and pixel offset-tracking techniques. We calculated coseismic 3D displacements with a prevailing strain model and variance component estimation method and then inverted the source model of this earthquake. The results reveal a high-angle (58°) thrust fault with a significant strike-slip component. The maximum slip of 3.3 m is concentrated at 13 km depth, and the estimated seismic moment is 4.01×1019 N·m, equivalent to an Mw 7.04 event. The postseismic slip inverted from 10-month Interferometric Synthetic Aperture Radar displacements exhibits a spatial pattern complementary to the coseismic slip, suggesting that the coseismic rupture was likely inhibited by rate-strengthening zones. Integrated analysis of inter-, co-, and postseismic geodetic data further reinforces the evidence that the southwestern Tian Shan region is characterized by slip partitioning, with ongoing compression and left-lateral motion in the intermontane areas.