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There has been no consensus yet regarding the precise initial timing and duration of the late Mesozoic extensional tectonics in the South‐eastern China Block. This work focusses on the growth strata of the Early Cretaceous red beds in the South‐eastern China Block to determine the late Mesozoic tectonics and the precise timing of the initiation and duration of extensional tectonics in this area. Field observation of several terrigenous basins shows that the dip angles of the Cretaceous red beds have varied from moderate to gentle from basin edges to interiors (or centres). The visible and estimated thickness within a single bed increases slightly downwards from the upper to the lower part. These characteristics indicate that the sedimentary area of these beds has undergone an extensional process with expansion and deepening of the sedimentary basins. Rotation of the border surfaces (limbs) and downward warping of the hanging walls or retreat of the footwalls of listric normal faults causes three types of extensional growth (or syntectonic) strata in the deposits of different basins. Dating of the volcanic rocks related to the growth beds reveals that the sedimentary basins were enlarged and deepened when the Early Cretaceous strata were deposited in the South‐eastern China Block from ca 140 to 137 Ma. Regionally, under the influence of Palaeo‐Pacific plate rollback since ca 140 Ma, the South‐eastern China Block stress field has led to lithospheric uplift and pull‐apart structures near the surface, causing the half‐graben basins to receive sedimentation. Although the extensional event was interrupted by a short compressional event during 120 to 105 Ma, with the oceanward retreat of the trench, the area of extension gradually enlarged and rejuvenated south‐eastwards until the end of the Cretaceous. This Cretaceous extension event of the South‐eastern China Block must belong to a worldwide geological event with global significance. [ABSTRACT FROM AUTHOR]

The E-W Kanggur tectonic belt, a major tectonic belt in the Eastern Tianshan (ETS) of the Central Asian Orogenic Belt (CAOB), records the amalgamation history between the ETS and the Tarim Craton. Two generations of structural deformation (D1 and D2) are recognized by field observations in the Jingerquan, Huangshan-Jingxia, Yamansu North Mountain, and Nanbeidagou-Kanggurtag areas. Early deformation is exhibited by vertical 'A' type (asymmetrical and symmetrical) S0 folds, lenticular symmetrical boudins, S-C fabric, and nearly vertical S1 foliation, demonstrating an ~N-S compressional setting. Late deformation is characterized by ~E-W-trending dextral shearing and local S1 folding. Transpressional deformation explains the kinematic compatibility of these fold and shear structures. The new U-Pb zircon and Ar/Ar age data in this study provide constraints on the timing of deformation, suggesting that D1 occurred in the late Carboniferous-early Permian (300–286 Ma) and that dextral shearing (D2) likely occurred in the middle-late Permian (262–233 Ma). The ~N-S contraction was driven by orogenic thickening during the convergence of the North Tianshan (NTS) island arc system, the Central Tianshan (CTS), and the Tarim Craton. Dextral transpression is related to the oblique convergence between the Eastern Tianshan (ETS) and Tarim Craton. On a larger scale, dextral kinematics along the Main Tianshan Shear Zone in the Eastern and Western Tianshan, together with sinistral shearing in northeastern Kazakhstan and the Chinese Altai, accommodated the eastward escape of central orogenic materials, which were possibly affected by the convergence of the Siberian, Baltic, and Tarim Cratons. [ABSTRACT FROM AUTHOR]

The late Mesozoic tectonic domain of Southeast China transitioned from compression to extension because of the Paleo-Pacific plate rollback. However, the precise timing of the initiation of extensional tectonics remains unclear. This work focuses on the E–W-trending granite belt and the growth strata of Early Cretaceous red beds in Southeast China to establish the extensional tectonic model in Southeast China. The petrogenesis of four granitic plutons from the E–W-trending granite belt in NE Jiangxi is traced on the basis of zircon U–Pb ages and whole-rock major and trace element abundances to elucidate lithosphere evolution in the study area. U–Pb zircon dating reveals the granite emplacement at 130–135 Ma. Geochemical results demonstrate that all granite intrusions can be identified as A-type granites derived from crustal and a few mantle sources respectively through lithospheric thinning and magma upwelling under the extension background. Field observation shows the enlargement of the sedimentary area of the early Cretaceous Huizhou Formation (Fm.) in the Huangshan Basin closely after (or simultaneously) 139 Ma Shiling volcanic activities. The dip angles of the lower part of Huizhou Fm. vary from 49° to 25° towards the basin centre, and the thickness exhibited a slightly increasing trend towards the lower part within the same bed. These phenomena are consistent with the shape of the growth strata. A model, in which the NE–SW-oriented structure lines transfer to the E–W-trending tectono-magmatic belts by meeting and inheriting the previous E–W-trending tectonic axis, is established in the present work. Lithospheric thinning, magma upwelling, and crustal remelting occur within an oblique extension stress field since ca. 140 Ma. Consequently, these phenomena are influenced by the Paleo-Pacific plate rollback and the inheritance of a structural framework from the regional basement series. [ABSTRACT FROM AUTHOR]

The north–north‐east‐trending (NNE) shear zones, which are defined by the Jiekou shear zone and Huangmao shear zone, are located in the eastern Jiangnan Orogen. This article provides kinematics, geochronological data, and dynamics on the Jiekou and Huangmao shear zones and serves as a reference for understanding the tectonic evolution in the South China Block during the Early Palaeozoic orogeny. All shearing signatures show that the Huangmao shear zone is dextral, and the Jiekou shear zone is sinistral. Both shear zones have certain genetic connections. The rocks from the Jiekou and Huangmao shear zones are metamorphosed and deformed into protomylonite and mylonite. Results of the deformation fabrics of feldspar and quartz and quartz c‐axis fabric analysis indicate that the ductile deformation temperatures of the Jiekou shear zone sinistral shearing are ~400–500°C. Dextral shearing with medium–high temperature (450–550°C) is mainly recorded in the Huangmao shear zone. In combination with the previous geochronology, NNE‐trending sinistral and dextral shearing in the eastern Jiangnan Orogen occurred at 465–430 Ma, coeval with the Early Palaeozoic orogeny. Therefore, the geodynamics of the NNE‐trending shear zones is related to a major strain transformation from NW to WNW, which is remotely affected by the intracontinental convergence of Yangtze and Cathaysia blocks during the Early Palaeozoic orogeny. [ABSTRACT FROM AUTHOR]

The Mesozoic to Cenozoic mountain uplift, exhumation, and deformation of the SW Tianshan Mountains (Kyrgyzstan and Northwest China) offer an important window to understand the intra-continental rejuvenation mechanism of the Central Asian Orogenic Belt (CAOB), as response to the far-field effects of the India-Asia collision. This article presents new observation and data for the planation surface and sedimentation and deformation features of the regional intermountain basins to rebuild the orogenic history in Mesozoic to Cenozoic. Three planation surfaces were recognized by field observation, showing that the mountain may have experienced lengthy erosion since the end Cretaceous, and a continuous planation surface may have formed at the Eocene to Oligocene. The filling sequences and deformation character revealed that the orogenic disintegrate and intermountain basin formation likely began in the end of Oligocene. Subsequently, the uniform planation surface in Western Tianshan may have begun to disintegrate, leading to the basin-and-range landform formation. Folds and nappes in the Cenozoic basins, large-scale thrusting of Palaeozoic rocks over Cenozoic sediments at the basin margin associated with the rapid mountain uplift may have occurred at the end of Early Pleistocene, suggesting a tectonic inversion. The Mesozoic-Cenozoic Tianshan uplift and deformation were likely induced by the collision/accretion along the southern margin of Eurasia. Both the northward propagation of the Parmir syntaxis to the SW Tianshan and the oblique dextral faulting of the Talas-Fergana fault have likely played an important role on the formation and deformation of the Cenozoic basins in the SW Tianshan. [ABSTRACT FROM AUTHOR]