The Yangtze foreland fold-and-thrust belt is located between the Mesozoic Dabie collisional orogen and the Mesozoic Jiangnan intraplate orogen in east-central China. Three regional deformation events are recognized in the Dabie Orogen north of the Yangtze River. The earliest regional deformation (D1) corresponded to a southeastward compression that occurred during the subduction of the South China Plate below the North China Plate. Top-to-the-southeast shearing coeval with Late Permian-Early Triassic blueschist facies metamorphism, was possibly associated with the development of regional gneissosity in the Dabie complexes and flat-ramp-style thrusts within the NeoproterozoicPalaeozoic sedimentary cover, north of the Yangtze River. The main ductile deformation (D2) is also characterized by southeast-verging overturned and recumbent folds, coeval with the early stage of exhumation of the high-pressure rocks. A top-to-the-SW thrusting and WNWstriking open folds belong to a separate, later deformation phase, D3. Previous 40 Ar-39 Ar mica dates ranging between 245 and 205 Ma suggest Late Permian-Early Jurassic ages for the D1 to D3 events. The foreland folds and thrusts related to these deformations in the Dabie Orogen flank the eastern and western 'limbs' of the Dabie Orogen but are absent in the front of it. In contrast to the deformation north of the Yangtze River, the deformation of Neoproterozoic-Palaeozoic sedimentary cover in the Jiangnan Orogen south of the Yangtze River is generally characterized by north-verging folding and top-to-the-north thrusting from Triassic to Jurassic times. Based on the differences of deformation and structural polarity between the south and north areas of the Yangtze River, we propose that the Yangtze foreland fold-and-thrust belt in the direct front of the Dabie Orogen is unrelated to the Dabie Orogen but resulted from the Jiangnan Orogen.

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The left‐lateral strike‐slip Altyn Tagh fault that defines the northern margin of the Tibetan Plateau plays a crucial role in accommodating the Cenozoic deformation related to the growth of plateau. However, the slip history along the fault remains highly debated. Here we report new 14–16 Ma apatite fission track (AFT) and 9–11 Ma apatite (U‐Th)/He (AHe) data in the western Danghenan Shan, north Tibet. Age‐elevation relationships and AFT/AHe age differences suggest a period of rapid exhumation with an average rate of 0.1–0.3 km/Ma from 16 to 9 Ma for this area. Thermal history modeling indicates that this was preceded by accelerated exhumation between the late Oligocene and middle Miocene (~15 Ma). A northward increase in AFT ages and asymmetric topography across the western Danghenan Shan indicate that the uplift and exhumation are mainly controlled by the thrust fault along the southern flank of the western Danghenan Shan. As the thrust fault is a branch of the Altyn Tagh fault, the rapid exhumation probably represents onset of the transition along the Altyn Tagh fault from left‐slip motion to crustal shortening in the Dangnenan Shan region. Our findings show that the middle Miocene deformation is not only recorded in the middle and northern Qilian Shan but also in the southwestern portion of the Qilian Shan, which favors a synchronous middle‐Miocene deformation model for the entire Qilian Shan.

Spatial and temporal patterns of mountain building in the northeastern Tibetan Plateau provide important constraints on competing plateau growth models. We focus on the East Kunlun Shan (EKLS), where the timing of Cenozoic deformation remains controversial. Seven apatite (U‐Th)/He samples were collected around a tilted erosion surface in the middle segment of the EKLS. A break in slope at ∼25 Ma is identified along the paleodepth below the erosion surface, which we interpret to represent the onset of thrust faulting at northern margins of the EKLS. Published thermochronologic data from the South Qilian Shan and North Qilian Shan reveal tectonic uplift at 15–18 and 8–10 Ma, respectively, obviously later than thrust faulting in the EKLS. Our study supports that the northeastern margin of the Tibetan Plateau has migrated from the EKLS to North Qilian Shan since the late Oligocene.

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