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The dynamic evolution in an overriding plate remains a controversial issue. Cretaceous structures in the western Liaoning (WL) region of the eastern North China Craton (NCC), an overriding plate bordering the Pacific Ocean, provide insights into the dynamic evolution related to Paleo-Pacific Plate subduction. We present structural and fault-slip data from the Jurassic–Cretaceous basins in the WL region, together with previously published isotopic ages, to constrain structural and stress field evolution during the Cretaceous. These data reveal four phases of deformation in the WL region: tectonic shortening (D1) at 137–136 Ma, extension (D2) during 136–97 Ma, another shortening (D3) at the beginning of the Late Cretaceous, and relatively weak extension (D4) during the Late Cretaceous. Inversions of the measured fault-slip data yield NW–SE compression during D1, NW–SE extension during D2, NNW–SSE compression during D3, and N–S extension during D4. Deformation phases D1 and D3 correspond to shortening events B and C of the Yanshan Movement, whereas D2 corresponds to the peak destruction of the NCC in a back-arc extensional setting. The structural evolution indicates that the back-arc extension (D2) of the Early Cretaceous started immediately after the brief shortening event D1 and ended with another shortening event D3. Subsequently, the back-arc region underwent weak extension (D4) during the Late Cretaceous. A slab-driven model could account for the tectonic evolution in the eastern NCC. Periodic changes in the kinematics of the subducting Paleo-Pacific Plate are responsible for the alternation of the back-arc extension and compression in the overriding plate. [ABSTRACT FROM AUTHOR]

North China, one of the most populated regions in the world, is exposed to elevated seismic hazards and has experienced multiple M ≥ 8 earthquakes in the past 1,000 years. The recent 1976 Ms 7.8 Tangshan earthquake constitutes a vivid reminder of the tectonic activity. Yet, the tectonic origin of the regional seismic unrest remains poorly understood. Here, we use geodetic data to construct a kinematic model encompassing the North China Block (NCB) and its neighboring Amurian Block (AB) and the South China Block (SCB) to illuminate the link between lithospheric strain accumulation and seismic activity. Our analysis illuminates two east-west oriented left-lateral shear zones that decouple the AB from the NCB, the latter representing a collage of the North China Plain (NCP) and the Ordos Block (OB). Bookshelf faulting slices the NCP through a series of NNE-trending right-lateral and conjugate WNW-trending left-lateral shear zones. These shear zones drive historical and instrumental seismic activities. The NCB serves as a mechanical bridge accommodating the relative motion of the surrounding mobile tectonic units. In the far field, Pacific subduction at the Japan Trench, extrusion of the Tibetan plateau, and retreat at the Ryukyu trench cause internal strain within the NCB, leading to the frequent occurrences of destructive earthquakes. • The North China serves as a mechanical bridge linking the neighboring plates. • Primary sinistral shear zones decouple the Amurian Block and North China Block. • A secondary sinistral shear zone transects the North China Plain. • Dextral shear zones in the North China Plain are distributed in a bookshelf mode. • The shear zones broadly delineate recent instrumented seismicity. [ABSTRACT FROM AUTHOR]

[Display omitted] • The Early Cretaceous marine transgressive cycle in NE China resulted from the subduction of the Paleo-Pacific Plate. • The Cretaceous Jixi Basin suffered initial back-arc extension, regional back-arc extension and block-continent collision. • Study on basin tectonics and geochronology could clarify conflicts of endemic transgressions and global sea-level changes. The occurrence of abundant marine fossils from non-marine basins in NE China indicated a distinctive Early Cretaceous phase of marine transgressions along the NW Pacific margin. Such a transgression has not only profoundly shaped the regional climate and terrestrial ecosystem, exerting a critical influence on rise-radiation-extinction of the world-famous terrestrial Jehol Biota, but also significantly facilitated the accumulations of hydrocarbon source rocks in NE China. In light of a joint study on marine and non-marine fossils and newly reported high-precision geochronological data, the timing of the transgression had been constrained as the late Early Cretaceous, puzzlingly disagreeing with coeval global sea-level changes. Employing seismic reflections, drill-holes and well-exposed outcrops, this study achieves structural architecture and kinematics of the Jixi basin (in eastern Heilongjiang), west of the Paleo-Pacific subduction accretionary prisms, and firstly affords subduction-related tectonic origins for the transgressive cycle. Based on tectonic events constrained by this study, transgressive initiation (Barremian to early Aptian Didao Formation), climax (middle Aptian to early Albian Chengzihe Formation) and termination (latest Albian to Cenomanian Houshigou Formation) correlate with initial back-arc extension, regional back-arc extension and block-continent collision linked to the subduction of the Paleo-Pacific Plate, respectively. Utilizing the delicate anatomy of tectonic responses to subduction and block accretion tectonics along the NW Pacific margin, we throw light on enigmatic dynamics for the transgressive cycle, offering new insights into the conflicts of endemic transgressions and global sea-level changes. [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]

Convergent plate margins could have an immediate impact on intraplate deformation in the adjacent sedimentary basin. In the Tarim Basin, a strike-slip fault network in the Guchengxu High is adjacent to the Tethys (northern Tibetan Plateau). This paper uses high-quality 3-D seismic data to unravel the geometry and kinematics of the strike-slip fault network and the genetic relationship with the Tethys tectonics. Within the fault network, the left-lateral NNE- and ENE-oriented strike-slip faults are a result of sequential evolution rather than conjugate faults. The sub-vertical ENE-oriented strike-slip faults are widely spaced with stepping-segmented geometry in the west, whereas they are relatively clustered with larger vertical throws close to the Cherchen fault. They were interpreted as a series of the Cherchen fault-related structures due to oblique blocking of the Tazhong Uplift and block deflection. It responded to the Late Ordovician Altyn Tagh/Tarim collisional orogeny and the Cherchen fault. The NNE-oriented strike-slip faults are characterized by underlying sub-vertical faults and two layers of overlying normal faults. These NNE-oriented strike-slip faults have large transversal compressional components, commonly presenting reverse drags on both sides of the underlying sub-vertical faults. These NNE-oriented faults initiated on pre-existing discontinuities (extensional joints) and offset the ENE-oriented ones when NNW-oriented stress was transmitted to plate interiors during this Late Ordovician orogeny. Afterward, two layers of overlying normal faults formed due to dragging of the covers during the Middle Silurian–Early Carboniferous reactivation and the Late Carboniferous–Early Permian inversion, in response to subduction of the Kunlun Ocean and opening of the Paleo-Tethys Ocean, respectively. The strike-slip fault network in plate interiors evolved as immediate responses to the Tethys tectonics at plate boundaries. • The 3-D seismic data detailedly characterize the strike-slip fault network in the Guchengxu High. • The strike-slip fault network is a result of sequential evolution rather than a series of conjugate faults. • The strike-slip fault network in the Guchengxu High evolved in response to the Tethys tectonics at plate boundaries. [ABSTRACT FROM AUTHOR]

The Neoproterozoic Jiangnan accretionary orogenic belt recorded the accretion and collision of the Yangtze and Cathaysia blocks to form a stablized South China Block, but related geometry and kinematics is poorly constrained, leading to largely varied tectonic models. Here, we present detailed field investigation and kinematic analysis of the plutonic-metamorphic complexes in the Yuanbaoshan and Sanfang areas of the west Jiangnan orogenic belt, which enables identification of extensional granite-cored domes. In the dome margins, down-dipping lineations display a radial pattern and dome dominated foliations are extensively developed. The shearing structures within the plutonic-metamorphic complexes display extensional shearing surrounding the Yuanbaoshan and Sanfang granitic dome cores. Gneissic granites and massive ones from both the Yuanbaoshan and Sanfang plutons yield comparable crystallization ages of ca. 835–823 Ma that are within age errors of each other, as are the sheared recrystallized asymmetric quartz veins and mylonites dated at 831 Ma. Overall ages of the deformed Sibao Group and the undeformed overlying Danzhou Group, along with those of the granite plutons and mylonites, suggest formation of the granite-cored domes at ca. 835–823 Ma, coeval to the timing of emplacement of the granitic plutons. Locally, top-to-the-E thrusting structures are also observed in the west Yuanbaoshan and Sanfang areas and are inferred as at ca. 860–835 Ma, coinciding well with E- or SE- directed structures developed elsewhere in the Jiangnan orogenic belt, but in contrast with doming extensional shearing structures. Therefore, overall geometry and kinematics in the west Jiangnan belt indicate development of granitic dome related extensional ductile shearing deformation dated at ca. 835–823 Ma and a possible top-to-the-E compressional ductile thrusting deformation within 860–835 Ma. Given the previously inferred regional geology observations, along with age and chemical data across the Jiangnan orogenic belt, the dominant extensional shearing deformation in the region argue for a slab roll-back event within an accretionary belt, typical of domes-and-basins structures formed in accretionary convergent continental margin. The top-to-the-E thrusting is here interpreted as corresponding to compressional regime generated by the west directed subduction of oceanic crust beneath the northern Guangxi continental margin arc in the west Jiangnan orogenic belt. • Two stages of Neoproterozoic ductile deformation identified in the west Jiangnan accretionary orogenic belt. • The ca. 835–823 Ma extensional domes-and-basins were generated by a slab roll-back event in an accretionary belt. • The ca. 860–835 Ma top-to-the-E thrusting indicates west directed subduction beneath the western Jiangnan belt. [ABSTRACT FROM AUTHOR]

• Two stages of folds are identified on the northern margin of the North China Craton. • The D 1 folds were crossly superimposed by the D 2 folds and both formed in Paleozoic. • A dynamic transition occurred in middle Paleozoic in the northernNorth China Craton. Accretionary kinematic history of the Central Asia Orogenic Belt (CAOB) remains unclear in previous geological studies. Based on detailed structural analysis of newly identified folds on the northern margin of the North China Craton (NCC), we propose a tectonic model suggesting that Paleozoic accretion of the orogenic belt includes two phases of deformation. The first phase of deformation is oblique collision of the Bainaimiao Arc and the NCC, which was followed by orthogonal subduction of the Paleo-Asian Ocean in the second phase of deformation. The change of plate kinematics is supported by two generations of folding, namely D 1 (D B) and D 2 (D A). Both D 1 (D B) and D 2 (D A) folds developed in the Bayan Obo Group (BOG), a Meso- and Neoproterozoic rift sequence deposited on the passive continental margin of the NCC. D 1 (D B) folds were superimposed by the east-west trending D 2 (D A) folds. The D 1 (D B) folds developed as a result of oblique collision of the Bainaimiao arc and the NCC. The D 2 (D A) folds developed in response to the southward orthogonal subduction of the Paleo-Asian Ocean Plate. They formed between latest Silurian and Early Permian, coeval with the two accretion events at the northern edge of the NCC. Our study suggests that multiphase deformation of sedimentary layers on the subducting plates provide important constraints for kinematic evolution of plate tectonics. [ABSTRACT FROM AUTHOR]

The basin-bounding fault system along the southeastern margin of the Ordos Block records three stages of extensional deformation during the Quaternary. This Quaternary deformation in the uppermost crust is possibly related to crust-mantle decoupling. • Three stages of extensional deformation were established during the Quaternary. • Transformation of kinematics resulted in transition of geomorphic pattern. • Quaternary extensional deformation resulted from the crust-mantle decoupling. The southeastern margin of the Ordos Block (SEMOB) is located at the juncture of the North China Block, the Ordos Block, and the Qinling Orogen. A series of faulted basins has developed in this area since the Cenozoic. The latest focal mechanism solution and stress field analyses indicate that the SEMOB is located at the adjacent regions of present different stress field, although the structural activity and internal mechanisms of this changing remain unclear. In this paper we describe the results of a study into the fault systems and Quaternary deformation between the Linfen and Weihe basins on the SEMOB. Based on the deformation sequences, kinematic analyses and activity timing, we found that the strain field in SEMOB underwent three evolutionary stages during the Quaternary: NW–SE extension in the early Pleistocene, NE–SW extension in the middle Pleistocene, and ca. N–S oblique extension from the late Pleistocene to the Holocene. This evolution of the strain field affected both the geomorphic patterns and the activity of paleo-earthquake events along the SEMOB during the Quaternary. Quaternary extensional deformation in the upper crust along the SEMOB possibly resulted from crust-mantle decoupling, which may be related to eastward expansion of the Tibetan Plateau and subduction of the Pacific and Philippine Sea plates. [ABSTRACT FROM AUTHOR]