On 2020 December 29, the M_w 6.4 Petrinja earthquake hit the Kupa Valley region and set a record for the largest earthquake in northwestern (NW) Croatia. The coseismic surface displacements are well obtained on three pairs of interferometric synthetic aperture radar images from Sentinel-1 satellites. The interferograms exhibit coseismic ground deformation with a maximum line-of-sight displacement of 0.4 m. Based on the coseismic deformation field, we investigate both the fault geometry and the coseismic slip distribution. The results show a dextral event with a peak slip of 3.50 m at a depth of 3.47 km. The shallow depth and unusually large coseismic slip correspond to obvious ground deformation and serious damage in the epicentral zone. The 2020 earthquake highlights an unmapped, steeply dipping strike-slip fault, which possibly enabled a potential ‘curve cut-off’ process on the bending segment of the Pokupsko fault in the context of ∼N–S compression in NW Croatia. The large coseismic slip and high stress drop associated with the M_w 6.4 Petrinja earthquake are likely products of the geometrically complex fault zones and immature seismotectonic environment in NW Croatia.

We use mainly geodetic observations to constrain the fault geometry and coseismic distribution of the 2018 Kaktovik earthquake sequence, Alaska. We find that at least three faults were activated. The earthquake sequence ruptured mainly an ESE‐striking, SSW‐dipping strike‐slip fault and a secondary rupture on an SE‐striking, SW‐dipping normal fault. Slip also occurred on a small SSW‐striking fault plane, which is found first in geodetic data and further verified with geological data and focal mechanism solutions. We also map 6 months of postseismic deformation and find obvious displacements in the center of the Sadlerochit Mountains. A geological model is proposed to interpret the relationship between this earthquake sequence and the regional structure. We suggest that the 2018 Kaktovik earthquake sequence may first have occurred on a fault unknown prior to the mainshock and triggered slip on both the pre‐existing ramp structure below the Sadlerochit Mountains and a secondary structure.

The Mongolia plateau is the farthest intracontinental region of the India–Eurasia collision and is a transition zone between north–south convergence to the south in the Tien Shan and northwest–southeast extension to the north in the Baikal rift. Mongolia has experienced four M 8 earthquakes since 1905, but due to limited observations, the mechanism of these strong earthquakes and regional tectonics are poorly understood. The 11 January 2021 $Mw$ 6.7 Hovsgol, Mongolia, earthquake is the largest event that has occurred in the Hovsgol graben, which is noted for being the northernmost convergence region of the India–Eurasia collision and the youngest extension region of the Baikal rift. In this article, the coseismic displacements are retrieved by space geodesy for the first time in this region, providing good constraints for the deformation pattern. We use a finite‐fault inversion of InSAR and teleseismic data, and a backprojection analysis to reveal the rupture kinematics of this event. The geometry of the Hovsgol fault is determined as east‐dipping with a dip of 45°. The rupture process is characterized by a northwestward propagation with a moderate average rupture velocity of $∼2.0km/s$ and a complex slip pattern composed of two major slip patches with dimensions of $40km×20km$⁠. The oblique slip, illustrated by predominate extension and significant dextral striking, confirms the right‐lateral‐striking faulting in the Hovsgol rift, which indicates that the eastwardly north–south convergence across the southwest segment of the Baikal rift has decreased.

Impulse motion characterized by a large amplitude in the fault‐normal direction can be observed at near‐fault strong motion sites during strike‐slip earthquakes. The large pulse, which always causes high intensity and stronger damage to structures close to faults, is usually attributed to the directivity effect of rupture propagating along strike and the proximity to the fault. We present an analysis of such a large directivity pulse captured by the near‐fault high‐rate Global Navigation Satellite System (GNSS) during the 2022 $Mw$ 6.7 Luding, China, earthquake—the largest event ever observed by space geodesy on the seismically active Xianshuihe fault in the eastern Tibetan Plateau. We invert the displacement waveforms and offsets derived from the continuous and campaign GNSS for the rupture kinematics. The inferred slip model reveals a rupture zone of 30 km in length above 15 km depth along the Moxi segment, yielding a seismic moment of $1.1×1019N·m$ and a source duration of 13 s. The high‐rate GNSS (hrGNSS) waveforms suggest an asymmetric bilateral rupture: most slips with long rise time are concentrated on the southern part of the ruptured fault, whereas a short‐duration pulse‐like slip rate with low final slip propagates during the northward rupture. We found that the directivity pulse observed by the nearest hrGNSS site is controlled primarily by the sharp pulse‐like slip rate and rapid rupture velocity approximating the local S‐wave velocity. Along with additional local amplification, this large directivity pulse may be responsible for the heavy damage in Moxi town close to the northern ruptured fault.

Exploring the deformation mechanism of the 2021 Mw 7.4 Maduo Earthquake is crucial for better understanding the seismic hazard of the faults with low strain rates inside the Bayan Har block. This study leverages deformation information derived from Sentient-1 A/B images and GPS data to investigate in detail the co- and postseismic deformation mechanisms using multiple methods. The main results are as follows. First, the postseismic InSAR time series robustly identified the reactivation of the Changmahe fault, indicating the impact of the Maduo event on surrounding active faults. Second, the joint inversion of Interferometric Synthetic Aperture Radar and GPS revealed that (1) there was a complementary and partially overlapping relationship between the coseismic slip and postseismic afterslip of the main rupture; and (2) the Changmahe fault exhibited thrust compression dislocation in the early stage and experienced a sustained compressive effect from afterslip in the one year after the mainshock. Third, modeling the processes of viscoelastic relaxation and poroelastic rebound revealed that the postseismic deformation was probably caused by a combination of afterslip (near-field) and viscoelastic relaxation (near and far field). Fourth, the stress changes driven by the Maduo event revealed that the seismic gaps inside the Maqin-Maqu segment and the Kunlun Pass-Jiangcuo fault will be potential seismic risks in the future.