In June 2019, an earthquake sequence comprising five M > 5 events occurred in a region of southwest China with fluid injection for both hydraulic fracturing and salt mining, which raised an extensive controversy on the cause. Here we use interferometric synthetic aperture radar (InSAR) observations to determine the source parameters of the sequence and to investigate the relationship with local injection activities. Both Sentinel‐1 and Advanced Land Observing Satellite 2 SAR images are collected to measure coseismic and preseismic surface deformation. Geodetic inversions with coseismic observations show that the sequence ruptured a previously unmapped southwest‐dipping thrust fault above 3 km depth, which intersects with the open‐hole sections of wells for solution mining of salt. In the 4 months before the sequence, cumulative line‐of‐sight displacements near the wells are around 1–2 cm after correcting seasonal‐like deformation. Our results indicate that water injection likely enhanced pore pressure within the fault zone and thus contributed to inducing the sequence.

From 2017 to 2019, three destructive earthquakes (27 January 2017 Mw 4.7, 16 December 2018 Mw 5.2, and 3 January 2019 Mw 4.8) occurred in the Changning shale gas field in the southwest Sichuan Basin, China. Previous seismological studies attributed these events to hydraulic fracturing (HF), but were unable to identify the causative seismogenic faults and their slip behaviors. Here, we use Sentinel‐1 synthetic aperture radar data to measure surface deformation triggered by the three events and conduct geodetic inversions to characterize their rupture models. The resulting coseismic interferograms show prominent surface deformation with the maximum line‐of‐sight displacements of up to 4 cm. The inversion results show that all three earthquakes mainly ruptured sedimentary formations above the shale gas bed, in the upper 3 km of the crust, with slip magnitudes ranging from 8.5 to 15 cm, and stress drops ranging from ∼1.8 to ∼3.3 MPa. Their source faults intersect with horizontal HF wells, but do not root in the crystalline basement. Combined with the reported difficulty of increasing HF operation pressures prior to the three events, we argue that they were most likely induced by direct injection of pressurized fluids into the fault zones. Crustal deformation patterns inferred from regional topography and GPS velocities highlight that the Changning field is located within a triple junction region near the southeastern margin of the Tibetan Plateau with large deformation gradients; such conditions are not only favorable to the development of critically stressed faults, but also facilitate the occurrence of at least moderate magnitude earthquakes.

The mechanisms of unusual shallow intraplate earthquakes that occasionally occur in stable cratons remain poorly understood. Here we analyze coseismic and postseismic displacement fields associated with the 2016 Petermann Ranges earthquake in central Australia using interferometric synthetic aperture radar data. The earthquake ruptured a previously unmapped fault and was dominated by thrust slip motion of up to 95 cm within the top 3 km of the crust. Postseismic deformation analysis suggests that a combination of poroelastic rebound and afterslip are responsible for the observed signals. The inferred afterslip overlapping spatially with the coseismic rupture highlights that the postseismic slip is coupled with the pore fluid flow around the fault zones. Analysis of historic groundwater‐level changes suggests that shallow seismicity around the Petermann Ranges may have been triggered by environmental stress perturbations due to the fluctuations of groundwater level; however, it is not easy to document statistical significance of this correlation.

The 2018 M_W 7.5 Papua New Guinea earthquake is the largest earthquake instrumentally recorded in the Papuan Fold Belt since 1900. Based on a combined analysis of backprojection imaging and finite‐fault joint inversion, we determined a complex spatiotemporal rupture model of the mainshock. During the rupture process, three major asperities were ruptured successively with relatively low rupture velocities ranging from 1.9 to 2.3 km/s. The spatiotemporal evolution of the imparted Coulomb stress indicates that the rupture of the preceding asperity played an important role in triggering the delayed rupture of the adjacent asperity. Based on our rupture model, the upper bound of the radiation efficiency of this event is estimated to be 9.7–12.3%, a relatively low value, indicating that this earthquake is extremely dissipative. The high energy dissipation implies that the 2018 M_W 7.5 Papua New Guinea earthquake may be controlled by the immature seismogenic environment.

Although the Papuan fold and thrust belt (PFTB) is thought to accommodate convergence between the Pacific and Australian plates, the possible strain partitioning and its kinematic controls in the region are poorly understood. On 25 February 2018, a devastating M_w 7.5 earthquake jolted the southern area of the PFTB, central Papua New Guinea. The detailed imaging of the source parameters of this large earthquake is an urgent demand for a better understanding of the tectonism in the region. Here we used spaceborne interferometric synthetic aperture radar data to carefully determine the possible ruptured faults and associated fault geometries and further estimated the detailed slip of the 2018 M_w 7.5 earthquake. We find that the earthquake involved multiple faults failure, and a four‐segment fault model can reasonably produce the complex coseismic deformation, especially the observed bimodal displacements. The earthquake was dominated by reverse fault motion, and significant slip of up to ~0.7 m was documented on faults extending at depths great than 25 km. An integrated analysis of the fracture complexities suggests that possible strain partitioning in the PFTB could be tightly coupled with regional fault geometries and lithospheric properties. Our findings on the deep brittle failures suggest that crustal shortening across the PFTB could primarily control the growth of fold and thrust belt in the central Papua New Guinea.

Despite historically low seismic activity on the Maidan Fault (MDF), the sudden Mw 7.0 Wushi earthquake in early 2024 underscores the urgent need to assess the seismic risk on this fault. This study utilizes Global Navigation Satellite System and Interferometric Synthetic Aperture Radar data to image the spatial distribution of interseismic coupling before the Wushi event along the MDF. The four asperities we identified indicate a high seismic risk for the MDF, with potential magnitudes of Mw 7.5–7.6, Mw 7.5–7.7, Mw 7.0–7.2, and Mw 6.8–7.0. Specifically, the Maierkaiqi segment has already accumulated seismic moment comparable to previous event. Furthermore, our comparison of the interseismic coupling model with the coseismic rupture of the Wushi earthquake reveals that the shallow compliant zone, creeping patches, and irregular fault geometry collectively constrained the rupture propagation. The consistency between the rupture and high coupling area also suggests that the obtained coupling distribution may represent potential earthquake‐prone zones along the MDF.