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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 faultingThe short‐term geodetic measurements do not constrain the thrust fault kinematics in the northern Qilian Shan over geological timescalesMulti‐fault earthquakes may be common in the region as all of the shallow thrust faults are linked together by locked fault segments [ABSTRACT FROM AUTHOR]

The structural connectivity and kinematic relationship between the Altyn Tagh sinistral strike‐slip fault (ATF) and Qilian Shan fold‐and‐thrust belt along the north Tibetan margin east of 96°E is an important question for tectonicists interested in the evolving active deformation field of Central Asia and associated earthquake hazards of China's Hexi Corridor region. New results from a detailed 130‐km‐long N‐S magnetotelluric (MT) survey from the Qilian Shan to Beishan elucidates the locations and down‐dip orientations of major faults. Importantly, the results indicate that the Heishan‐Jinta'Nanshan fault system roots steeply into the lower crust, is unconnected to the Qilian Shan thrust wedge, and has reactivated the margin of the North China Craton and an older, regional ductile shear belt. The structurally linked ATF‐Heishan‐Jinta'Nanshan system defines a fundamental kinematic boundary in central Asia between the NE directed Qilian Shan thrust belt to the south and the eastwardly extruding Beishan‐Alxa Block to the north. Plain Language Summary: In this study, we present results of a comprehensive electrical resistivity survey conducted in the western Hexi Corridor region of China. The survey reveals significant sub‐surface faults and crustal boundaries, providing insights into the crustal structure between northernmost Tibet (Qilian Shan) and the Beishan. We document how the strike‐slip crustal boundary known as the Altyn Tagh Fault (ATF)‐Heishan‐Jinta'Nanshan system is steep and spatially unconnected to the Qilian Shan east of 98°E. It separates crustal blocks with contrasting motion histories; the southern block experiences compressional deformation, whereas the northern block accommodates extensional and transtensional deformation. Furthermore, the northeast trending ATF bends and converges into the more east‐west‐oriented Heishan‐Jinta'Nanshan system. We propose that this is a result of the Heishan‐Jinta'Nanshan system reactivating an older ductile shear belt and a mechanically weak boundary along the northwestern margin of the Precambrian North China Craton. Our study confirms the significance of inherited crustal structures in localizing continental interior reactivation and associated earthquake hazards. Key Points: A new detailed 3D resistivity model from Northern Tibet to the Southern Beishan clarifies the crustal structure in the NW Hexi CorridorThe Heishan fault system penetrates steeply to the lower crust and is unconnected to the Qilian Shan thrust wedgeCrustal thickening and mountain uplift in Qilian Shan is kinematically separated from eastward Beishan‐Alxa Block extrusion further north [ABSTRACT FROM AUTHOR]

Purpose: Para‐alpine sit skiers face unique challenges in balance control due to their disabilities and the use of sit skis. This study assessed their multi‐joint coordination before and after slackline training. Methods: Nine alpine sit skiers (6 M/3 F; 27 ± 8 years; height: 168.3 ± 6.0 cm; body mass: 55.4 ± 6.9 kg) with different disabilities (LW10‐LW12) volunteered for the experiment. All subjects performed slackline training for 5 weeks (20 sessions). Joint kinematics were captured by vision‐based markerless motion analysis. Root mean square (RMS) amplitude, mean velocity and mean power frequency (MPF) were evaluated. Results: After training, performance improved significantly with an increase in balance time (1041%, p = 0.002), and a decrease in joint angular velocities and RMS amplitude of the sit ski foot (p < 0.05). Joint synergies were developed through in‐ or anti‐phase movements between joint pairs, particularly involving the hip joints (continuous relative phase angles ~0° or 180°, p < 0.001). Multi‐joint coordination shifted from large‐RMS amplitude of elbows to low‐MPF large‐RMS amplitude of the hip and shoulders (p < 0.05), with a significant increase of hip weighting (77.61%, p = 0.031) in the principal component analysis. The coordination was maintained with the change of slackline tension (p < 0.05). Athletes with severe trunk disabilities (LW10) had shorter balance time and poorer coordination than athletes with full trunk functions (LW12). Conclusions: Our findings showed the development of joint coordination involving better control of the hip and sit skis during the challenging slackline training task. [ABSTRACT FROM AUTHOR]

Treadmill training is useful for racewalking training; however, it may affect gait characteristics and lead to non-legal techniques. The aim of this study was to determine the kinematic differences between treadmill and overground conditions during racewalking at different speeds. Twenty-two elite racewalkers participated in this study. They racewalked under treadmill and overground conditions at high and medium speeds. A 12-camera motion analysis system was used to record the racewalking trials. Significant condition by speed interactions were detected in step frequency and pelvis rotation angle; step frequency decreased while pelvis rotation angle increased from overground to treadmill conditions at high speed. Compared to overground conditions, racewalkers decreased the ankle dorsiflexion angle at heel strike and increased hip flexion, shoulder hyperextension, and elbow flexion angles at heel strike and hip and shoulder extension angles at toe-off under treadmill conditions. Compared to medium speed, racewalkers decreased the contact time, hip flexion, and shoulder hyperextension at heel strike, and ankle plantarflexion and shoulder extension angles at toe-off, and increased flight time, step length, and elbow flexion angle at heel strike at high speed. Several kinematic differences during racewalking were detected between treadmill and overground conditions, with more differences detected at high speed, indicating that treadmill racewalking, especially at high speed, has different gait characteristics. However, no differences were detected in flight time and knee angle under treadmill conditions compared to overground conditions, indicating that racewalking on a treadmill does not increase the risk of disqualification. [ABSTRACT FROM AUTHOR]

The North China Craton (NCC) is an important tectonic element in China, which is characterized by intense seismic activity and complex tectonic setting. Thus quantifying its deformation is essential for studying the tectonic processes and deformation mechanisms in this region. Here we use a combination of dense GPS data sets to analyze the crustal movement and present updated estimates of fault motions based on elastic block models. We uncover spatial variations in deformation patterns, indicating that different mechanisms may dominate the tectonic processes for different parts of the NCC. In the western part, the rifts around the Ordos block manifest strike‐slip and extensional deformation, and the strike‐slip motion is more significant than the extensional component; whereas in the east, the Tanlu fault experiences right‐lateral and shortening slips, consistent with the features from historical seismic activity and regional tectonics. Our analysis indicates that the deformation in the eastern NCC is principally influenced by the Pacific subduction, whereas the deformation in the western NCC is mainly related to the India‐Eurasia collision. Moreover, our estimate of motion along the Tanlu fault supports a relatively long seismic interval of ∼10 ka, comparable to those inferred from recent paleoseismic research on this fault and other slow‐slip faults in the NCC. Our study indicates that the faults in the NCC even with very slow motions may still have the potential to produce strong earthquakes. Thus seismic risks across these slow‐slip faults cannot be ignored and should not be determined solely based on the rate of fault motions. Plain Language Summary: North China is situated at the eastern part of the Chinese continent, which is characterized by intense seismic activity and dense population. Numerous strong earthquakes have occurred in this region that caused huge casualties during the past decades. Thus quantifying the fault slip rates is essential for understanding the deformation regimes and seismic risk assessments in this region. Here we use dense space‐geodetic measurements to analyze the crustal movement and fault motion in the study area. We reveal that the fault motion derived in our study exhibits distinct features of deformation from west to east of the region, implying that different regimes may dominate the tectonic processes in different parts of North China. Moreover, our analysis suggests that the faults even with very slow motions in this region may still have the potential to produce strong earthquakes. Thus, seismic hazards across these slow‐slip faults cannot be ignored and should not be determined solely based on the rate of fault motions. Key Points: We use dense GPS measurements and elastic block models to quantify the faulting kinematics and slip partitioning in North ChinaWe find spatial variations of kinematics, implying that different regimes may dominate tectonic processes for different parts of North ChinaSeismic risks along slow‐slip faults cannot be ignored and should not be determined solely based on the rate of fault motions in North China [ABSTRACT FROM AUTHOR]

While the morphology and evolution of the quadrate among early birds and through the evolutionary origin of birds is not well known, we add to knowledge about that past diversity through description of the morphology of the quadrate in the unusually elongate skull of the Cretaceous enantiornithine bird Longipteryx chaoyangensis. The lateral and caudal surfaces of the quadrate are well exposed in two specimens revealing morphologies typical of early birds and their dinosaurian close relatives like a small otic head and two mandibular condyles. However, both skeletons exhibit quadrates with a unique, enlarged lateral crest that has not been previously described among Mesozoic birds. It is possible that the rostral surface of this lateral expansion served as the origination site for enlarged jaw musculature in a manner similar to the enlarged subcapitular tubercle in extant galloanserine birds. The caudally concave surface of the quadrate likely reflects some aspect of cranial pneumaticity, with its shape and position reminiscent of quadrates found in close non‐avialan maniraptoran relatives. It is possible that this lateral crest has a wider distribution among enantiornithines and other early birds and that the crest has been misidentified as the orbital process in some more damaged specimens. In addition, the enlarged lateral mandibular condyle (relative to the medial condyle) differs from the condition typically reported among enantiornithines and could indicate a difference in jaw function or mechanics in this bird with an elongated rostrum, or simply misinterpretations of morphology. Further examination of the quadrate in temporally early and phylogenetically stemward birds, along with their close outgroups, could greatly impact the study of several different aspects of bird biology including assessment of phylogenetic relationships, interpretation of the function and kinematics of the skull, reconstruction of foraging paleoecology, and evolution of skull morphological diversity among Mesozoic birds. [ABSTRACT FROM AUTHOR]

The Tan–Lu Fault Zone (TLFZ) is the largest continental‐scale strike‐slip fault zone in East China. It experienced a complex Meso‐Cenozoic deformation and controlled the development and evolution of the Bohai Bay Basin (BBB). Though its Mesozoic sinistral and Cenozoic dextral motions have been well documented, its strike‐slip transition history and mechanism from sinistral to dextral motions in the Early Paleogene remain poorly understood. To investigate these issues, we made a thorough analysis on the fault geometry and kinematics as well as the response of depocentre in the Early Paleogene of the sags adjacent to the TLFZ across the southeast BBB. The results show that the WNW‐/NW‐, E‐W‐, and ENE‐/NE‐trending extensional faults developed in the Early Paleogene of those sags share almost the same geometrical and kinematic features. Such features indicate that the TLFZ is sinistral in Ek3‐Ek2 depositional stage, extension dominated in Ek1 depositional stage, and dextral in Es4L depositional stage. Such strike‐slip transition of the TLFZ is a comprehensive effect of the plate events around the Eurasian Plate. The NNW‐directed subduction of the Pacific to the Eurasian plates triggers the sinistral motion of the TLFZ during 65–55 Ma, but this sinistral motion is terminated by the far‐field effect of the NNE‐directed India–Eurasia collision initiating at 55 Ma. Then, the kinematic adjustment of the Pacific Plate from NNW to WNW breaks the stress balance exerted on the TLFZ by the subduction of the Pacific to Eurasian plates and the India–Eurasia collision and makes it turn into dextral motion gradually during 48–42 Ma. [ABSTRACT FROM AUTHOR]

The article discusses the Zanhuang tectonic mélange in the Zanhuang Massif of the Central Orogenic Belt in China which seperates the Eastern Block from an Archean arc terran. It is one of the best-preserved Archean tectonic mélanges in the world and contains complex tectonic mixture of metapsammites, quartzites mixed with volcanic rocks and metapelites. The article also presents diagrams of the kinematic framework in the mélange.