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The convergence of the Indian and Eurasian plates beneath the Pamir Plateau has produced complex continental subduction, significantly influencing upper crustal faulting and seismicity. To investigate the kinematic behavior of the High Pamir Plateau, we derive a geodetic slip model for the 2023 Mw 6.9 Pamir earthquake by using Sentinel‐1A and ALOS‐2 InSAR data. Our geodetic inversion reveals rupture along two distinct faults: a dominant left‐lateral strike‐slip fault and a secondary normal fault, consistent with the mechanisms of the 1911 Mw 7.3 and 2015 Mw 7.2 earthquakes in the region. Notably, the 2015 and 2023 ruptures extend to ∼20 km depth—deeper than typical Tibetan Plateau earthquakes—likely due to the thermal influence of the underlying cratonic lithosphere. Our results also indicate a broad shear zone above the underthrusting Indian plate, underscoring the role of lithospheric‐scale dynamics in shaping crustal fault behavior in the Pamir region.

The human tragedy caused by the earthquake doublet on 6 February 2023 in Turkey and Syria is difficult to comprehend. While earthquake scientists are trying to understand this seismic event, its catastrophic impact highlights heightened risk in the entire region.

The fast increase of convergence rate between India and Eurasia around 65 million years ago (Ma)—from approximately 8 cm yr −1 to a peak rate of approximately 18 cm yr −1 —remains a complex geological event to explain 1 , 2 , 3 , 4 , 5 , 6 , 7 – 8 , given the inherent uncertainty surrounding the tectonic history and the intricate interplay of forces influencing plate speed 9 , 10 – 11 . Here we use a combination of geochemical analysis and geodynamic modelling to propose that this rapid convergence can be explained by sediment subduction derived from the northern Indian passive margin. Through isotope and trace element analysis, we find an enhanced contribution of terrigenous sediment melt to the mantle source of the Gangdese magmatic rocks around 65 Ma, concurrent with the acceleration of India–Eurasia convergence. Numerical experiments suggest that subduction of sediments more than 1 km thick covering an approximately 1,000-km-wide ocean basin abutting the northern Indian passive margin starting from 65 Ma could have spurred the increased convergence rate and further led to significant crustal extension, consistent with empirical observations. Our study implies that the acceleration of India–Eurasia convergence marks the arrival of passive-margin-derived sediments, constraining the initial India–Eurasia collision to be around 60 Ma. It further suggests that temporary accelerations in subduction rates might be a common feature at the final stage of continental assembly. Geochemical data and geodynamic modelling suggest that the rapid increase of convergence rate between India and Eurasia about 65 million years ago can be explained by changes in sediment subduction.

Many oceanic and some continental transform faults host coupled tectonic shear and magmatism, complicating seismic and volcanic hazards. Here we integrate high-resolution seismic tomography and three-dimensional finite-element modelling to investigate fault–magma interactions along the eastern North Anatolian Fault Zone. Tomography reveals two shallow magma reservoirs beneath the Erzincan Basin and the Karlıova Triple Junction, characterised by high Vp/Vs (>1.85). The western reservoir is largely aseismic while the eastern reservoir has persistent seismicity. Time-dependent models demonstrate that right-lateral shear focuses tensile stresses around both reservoirs that encourage reservoir rupture and dyke injection. This stress concentration occurs even when the initial magma-generated excess pressure is zero, and may gradually expand towards the surface. Upward stress transfer is enhanced within the fractured damage zone, facilitating dyke propagation. The results may apply to many transform faults and are of great importance for evaluating the coupled earthquake–volcano hazards in such fault zones. The interplay between tectonic transform loading and evolving magma reservoirs in the eastern North Anatolian Fault Zone is potentially responsible for generating volcanic and seismic hazards, according to geophysical analysis and finite-element modelling.

There is increasing evidence that the Himalayan seismicity can be bimodal: blind earthquakes (up to Mw ~ 7.8) tend to cluster in the downdip part of the seismogenic zone, whereas infrequent great earthquakes (Mw 8+) propagate up to the Himalayan frontal thrust. To explore the causes of this bimodal seismicity, we developed a two-dimensional, seismic cycle model of the Nepal Himalaya. Our visco-elasto-plastic simulations reproduce important features of the earthquake cycle, including interseismic strain and a bimodal seismicity pattern. Bimodal seismicity emerges as a result of relatively higher friction and a non-planar geometry of the Main Himalayan Thrust fault. This introduces a region of large strength excess that can only be activated once enough stress is transferred upwards by blind earthquakes. This supports the view that most segments of the Himalaya might produce complete ruptures significantly larger than the 2015 Mw 7.8 Gorkha earthquake, which should be accounted for in future seismic hazard assessments. There is increasing evidence that the seismicity of large Himalayan earthquakes can be bimodal, but the underlying mechanisms are unclear. Here, the authors present a model and show that the bimodal seismicity results from a relatively higher friction and a non-planar geometry of the Himalayan megathrust.

A M6.8 earthquake struck the High Atlas Mountains in Morocco on 8 September 2023, ending a 63‐year seismic silence. We herein attempt to clarify the seismogenic fault and explore the underlying mechanism for this seismic event based on multiple data sets. Utilizing probabilistic Bayesian inversion on interferometric radar data, we determine a seismogenic fault plane centered at a depth of 26 km, striking 251° and dipping 72°, closely aligned with the Tizi n’Test fault system. Given a hypocenter at the Moho depth, the joint inversion of radar and teleseismic data reveals that the rupture concentrates between depths of 12 and 36 km, offsetting the Mohorovičić discontinuity (Moho) at ∼32 km. Considering a strong link between magma activity and failure in lower crust, we propose that the triggering of the earthquake possibly was mantle upwelling that also supports the high topography. Plain Language Summary On 8 September 2023, a devastating earthquake with a magnitude of 6.8, struck the High Atlas Mountains in Morocco, breaking a 63‐year seismic silence. In this work we utilized geodetic, seismic, and seismicity data to investigate the earthquake, pinpointing its origin within the Tizi n’Test fault system at 12–36 km depths and causing displacement of the Mohorovičić discontinuity (Moho), where Earth's crust meets the mantle. Highlighting the impact of the mantle upwelling, this event underscores its significance in shaping regional topography and driving crustal deformation along established faults, leading to unusual, significant seismic activity in areas of minimal plate convergence. This earthquake highlights the importance of incorporating deep crustal dynamics into seismic hazard evaluations, challenging traditional risk models with its implications on earthquake genesis far from tectonic boundaries. Key Points Interferometric radar data, Bayesian inversion techniques and teleseismic data reveal the seismogenic fault and underlying mechanisms The seismogenic fault centered at a depth of 26 km, striking 251° and dipping 72°, closely aligned with the Tizi n’Test fault system We propose that the 2023 M6.8 earthquake in Morocco was possibly triggered by mantle upwelling on a steep fault that offsets the Moho

In this study, we utilize C‐band Sentinel‐1 radar images from 2015 to 2022, combined with interseismic horizontal GNSS velocities, to construct large‐scale, high‐resolution, 3‐D velocity and strain rate maps over a vast region of southern Tibet. We show the distribution of prevailing dilatational strain accumulation along the seven major rift zones. Using 2‐D elastic dislocations invoking a two‐fault model in a Bayesian framework, we quantified the decadal extension rates across the seven rift zones, and we suggest a total extension rate of 18.4 ± 1.7 mm/yr, consistent with geological and geodetic estimates. The resulting strain rate maps, combined with the earthquake catalog, help us identify areas with high earthquake potential. Our study enhances our understanding of the present‐day tectonics and kinematics in southern Tibet and provides important constraints for seismic hazard assessment in this region. Plain Language Summary In this research, we used satellite radar images from 2015 to 2022 and GNSS data to study the crustal deformation and strain distribution in southern Tibet, where the Earth's crust is actively stretching due to the collision of the Indian and Eurasian plates and the extrusion of crustal materials. By analyzing high‐resolution 3D velocities, we provided new high‐resolution surface strain maps over southern Tibet. We found that the widespread dilatational strain is mainly localized along seven major N‐S trending rift zones. Seven major rift zones are experiencing extension at a total rate of 18.4 ± 1.7 mm/yr. The strain rate maps, combined with historical earthquakes, helped us identify fault segments that are more likely to host earthquakes in the future. By mapping deformation and strain in greater detail, we provided valuable data that can improve our understanding of kinematics and earthquake risk assessments in geologically complex southern Tibet. Key Points We present InSAR‐based, high‐resolution maps of 3‐D velocities and strain rates in Southern Tibet There is prevailing dilatational strain along seven rift zones in Southern Tibet, with a total extension rate of 18.4 ± 1.7 mm/yr We show the distribution and spatial variations of extension rates for seven rift zones

The 2023 M7.8 and M7.5 earthquake doublet near Kahramanmaraş, Turkey, provides insight regarding how large earthquakes rupture complex faults. Here we determine the faults geometry using surface ruptures and Synthetic Aperture Radar measurements, and the rupture kinematics from the joint inversion of high-rate Global Navigation Satellite System (GNSS), strong-motion waveforms, and GNSS static displacement. The M7.8 event initiated on a splay fault and subsequently propagated along the main East Anatolian Fault with an average rupture velocity between 3.0 and 4.0 km/s. In contrast, the M7.5 event demonstrated a bilateral supershear rupture of about 5.0–6.0 km/s over an 80 km length. Despite varying strike and dip angles, the sub-faults involved in the mainshock are nearly optimally oriented relative to the local stress tensor. The second event ruptured a fault misaligned with respect to the regional stress, also hinting at the effect of local stress heterogeneity in addition to a possible free surface effect. The February 2023 Kahramanmaraş earthquake doublet reveals how pre-stress and local stress heterogeneity influence fault ruptures, with key insights into rupture kinematics, fault geometry, and stress interactions along complex fault systems.

Oblique convergence across the northern Qilian Shan is accommodated by sub‐parallel strike‐slip and thrust faults that ruptured simultaneously in the Mw 8 Gulang earthquake in 1927. We investigate the kinematics of fault loading in the northern Qilian Shan and provide insights into the conditions necessary for generating multi‐fault earthquakes. We perform Bayesian inversions for the geometry and creep rate on the fault network. We infer that all of the thrust faults are locked north of the Qilian‐Haiyuan strike‐slip fault and are accumulating elastic strain. Multi‐fault earthquakes may occurr in this fault system because the faults are simultaneously loaded by the same source of deformation and are linked together by locked fault segments. The interseismic velocity field alone can not contain the location or activity of individual faults visible in the geomorphology, therefore the short‐term geodetic measurements may not reliably indicate the long‐term behavior of the fault system. Plain Language Summary This study aims to understand the earthquake hazard in the northern Qilian region of China. We use measurements of ground deformation between earthquakes to infer how the faults are being loaded in the region. We find that the ground deformation can be explained by a simple model with a single, slowly creeping fault at depth that loads all of the overlying faults. Large earthquakes that were caused by slip on many different faults at the same time have occurred in this region before. We suggest these so‐called “multi‐fault” earthquakes may occur because all of the faults are being simultaneously loaded by the same source of stress. Key Points Oblique convergence in the northern Qilian Shan is accommodated by sub‐parallel thrust and strike‐slip faulting The short‐term geodetic measurements do not constrain the thrust fault kinematics in the northern Qilian Shan over geological timescales Multi‐fault earthquakes may be common in the region as all of the shallow thrust faults are linked together by locked fault segments