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The Cenozoic sediments are very thick in the southwest Tarim Basin and very thin in the northwest, but what controls these variations is unclear. Here, we use two‐dimensional thermo‐mechanical models to investigate how the lateral variations in rheological strength and depletion density of cratonic lithosphere mantle affect the cratonic basin deformation. Model results show that the basin basement uplift occurs above either the region with crustal thickening or high depletion in the mantle. A model with a stronger and density‐depleted northern half of cratonic lithosphere mantle in the context of compression matches the differential Cenozoic subsidence and deformation observed in the Tarim Basin well. We propose that a Permian plume led to the lateral heterogeneity of the lithosphere mantle under the Tarim craton, and the modified lithosphere mantle characteristics caused the differential Cenozoic sediment thickness in the Tarim Basin. Plain Language Summary: Tarim Basin is a typical intraplate cratonic basin in northwest China. It is bounded by the West Kunlun Shan to the south and the Tian Shan to the north, respectively. The Cenozoic sediment thickness in the Tarim Basin displays significant lateral variation, which cannot be explained by flexural bending of the Tarim lithosphere under orogenic loads of the West Kunlun Shan and Tian Shan. Recent geophysical data outlined the extent of the Permian plume head, which coincides with the region covered by thinnest Cenozoic sediments. Here, we conduct a series of 2‐D thermo‐mechanical numerical simulations to examine the correlation of the cratonic lithosphere mantle characteristics with cratonic basin's basement geometry. Model results show that a craton with a stronger and density‐depleted northern half of lithosphere mantle in the context of compression matches well with the south‐north differential Cenozoic subsidence and deformation in the Tarim Basin. Accordingly, we suggest that the differential Cenozoic sediment thickness in the Tarim Basin was likely caused by the Permian plume‐modified lithosphere mantle. Our study indicates that the plume‐modified mantle characteristics play a critical role in the basement deformation of the above sediment basin. Key Points: The strength and depletion density of cratonic lithosphere mantle control the deformation of cratonic lithosphere underlying sediment basinThe differential Cenozoic sediment thickness in the Tarim Basin is related to the heterogeneity of cratonic lithosphere mantleThe lithosphere mantle heterogeneity under the Tarim craton was likely caused by post‐Permian plume‐driven recratonization [ABSTRACT FROM AUTHOR]

The India–Eurasia collision has produced a number of Cenozoic deep intracontinental basins, which bear important information for revealing the far‐afield responses to the remote collision. Despite their significance, their subsiding mechanism remains the subject of debate, with end‐member models attributing it to either orogenic or sedimentary load. In this study, we conduct flexural subsidence modeling with a two‐dimensional finite elastic plate model on the Hotan–Mazatagh section along the southern Tarim Basin, which defines a key region in the foreland of the West Kunlun Orogen, along the NW margin of the Tibetan Plateau. The modeling results indicate that the orogenic load of West Kunlun triggers the southern Tarim Basin to subside by up to less than ∼6 km, with its impact weakening towards the basin interiors until ∼230 km north from the Karakax fault. The sedimentary load, consisting of Cenozoic strata, forces the basin to subside by ∼2 to ∼7 km. In combination with the retreat of the proto‐Paratethys Sea and the paleogeographic reorganization of the Tarim Basin, we propose that surface processes, in particular a shift from an exorheic to an endorheic drainage system associated with the consequent thick sedimentary load, played a decisive role in forming deep intracontinental basins in the context of the India–Eurasia collision. [ABSTRACT FROM AUTHOR]

The West Kunlun orogenic belt, which defines the northwestern margin of the Tibetan Plateau, holds important information on plateau growth. Despite its significance, views about its uplift history continues to be under debate, with two competing hypotheses involving episodic uplift or northward expansion, related to a fixed or movable plateau boundary, respectively. The Buya Basin, a small basin located between the North and South Kunlun terranes, is key to understanding the Cenozoic uplift history of the West Kunlun orogenic belt. In this study, we conducted sedimentary and detrital zircon U Pb geochronological analyses on the Cenozoic sediments of the Buya Basin. According to the findings of the sedimentary investigation, the Cenozoic strata of the basin generally show gradual changes from low- to high-energy deposition interrupted by a reverse trend in the Anjuan Formation. Moreover, the detrital zircon U Pb geochronological results indicate that the Buya Basin received sediments initially from the Songpan–Ganzi and South Kunlun terranes during the deposition of the Keziluoyi to Pakabulake formations and then from the South and North Kunlun terranes during the deposition of the Artux Formation. This change in sediment dispersal patterns demonstrates that the uplift of the West Kunlun orogenic belt has expanded northwards to the North Kunlun terrane, which suggests that the northwestern boundary of the Tibetan Plateau has been a northward-moving feature in the context of India–Eurasia convergence. Along with previous studies, we suggest that the northward expansion of the northwest Tibetan Plateau is accommodated by decoupling deformation along the southern Tarim Basin, with northward thrusting of the foreland fold-and-thrust belts in the upper crust and southward underthrusting in the lower plate. • Buya Basin experienced low- to high-energy deposition during Cenozoic. • Reorganization of sediment dispersal at Artux Formation period. • NW Tibetan Plateau expanded northward. [ABSTRACT FROM AUTHOR]

The Eastern Tian Shan, one of the most active intracontinental orogenic belts, should bear important information on the mechanisms of intracontinental mountain building. In this study, detrital zircon U-Pb geochronological analysis of the Cenozoic Tiereke section succession in the northern Tarim Basin-Eastern Tian Shan convergence zone, combined with stratigraphic results, reveals the provenance histories of the Cenozoic sediments in the northwestern Kuqa Depression of northern Tarim Basin. Nine Cenozoic samples obtained from the strata of the Kumugeliemu Group to the lowest Kangcun Formation of the Tiereke section exhibit high resemblance to provenances of the south-Eastern Tian Shan, indicating existence of a prolonged eroding relief within this mountain since the early Cenozoic (∼54 Ma). This prolonged state of eroding relief requires continuous intracontinental deformation of the Eastern Tian Shan to sustain a provenance region, implying immediate deformation responding to the initial Indian-Eurasian collision. Furthermore, the south-Eastern Tian Shan served as the only source region for the northwestern Kuqa Depression of northern Tarim Basin, demonstrating that the upper-crustal boundary between the south-Eastern Tian Shan and the northern Tarim Basin was possibly stationary during most of the Cenozoic Era (∼54 Ma to ∼9.7 Ma). Such a stationary basin-orogenic boundary would favor the predictions of the pure-shear-like thickening model for the intracontinental mountain building during this period. We suggest that the long-lived mountain building of the Eastern Tian Shan may be due to its small convergence rate. • Kuqa Depression received sediments from south-Eastern Tian Shan during ∼54–9.7 Ma. • N. Tarim-Eastern Tian Shan boundary was a stationary feature. • Uplift of south-Eastern Tian Shan driven by pure-shear-like crustal thickening. [ABSTRACT FROM AUTHOR]

The western Kunlun thrust belt defines the boundary between the stable Tarim Basin in the north and the intensely deformed Cenozoic Tibetan Plateau in the south. Because of its important tectonic position, understanding its tectonic evolution should have important implications for propagation of deformation from Tibet to its neighboring cratonal regions during India-Eurasia convergence. We here present new structural analyses based on field investigations and seismic reflection profiles across the Hotan-Tiklik segment of the western Kunlun thrust belt. The results indicate that the structural section crosses two major thrust zones: the Tiklik zone in the hinterland to the south and the Hotan zone in the foreland to the north. Within these, the Hotan thrust zone is thin skinned, with its deformation characterized by fault-bend folding and fault slipping along detachment layers, whereas the Tiklik thrust zone involves basement, with its deformation driven by the currently steeply dipping Tiklik fault. Results from apatite fission track thermochronology in combination with growth strata and balanced cross section indicate that the Hotan-Tiklik segment underwent two-stage deformation: (1) development of the Tiklik thrust during the late Oligocene–early Miocene and again since the mid- to late Miocene and (2) activity of the Hotan thrust since the mid- to late Miocene as a result of basinward propagation of thrusting. The balanced cross section, combined with the apatite fission track results, suggests that the Hotan-Tiklik segment contributes a total shortening magnitude of more than ca. 34 ± 6 km. Within this, ca. 4 ± 2 and ca. 23 ± 1 km of the shortenings were absorbed by the Hotan anticline and the Hotan detachment fault, respectively, both of which were related to detachment layers. This suggests that detachment layers played an efficient role in propagating deformation from the western Tibetan Plateau into the Tarim Basin. [ABSTRACT FROM AUTHOR]

Defining the northern margin of the Tibetan Plateau, the Altyn Tagh Fault system (ATFs)exerts a crucial role in accommodating intracontinental deformation during the India-Asiaconvergence. The North Altyn fault (NAF), demarcating the western boundary of the ATFs inthe Altun Shan region, was testified to exist a structural shift from sinistral along-strikeslipping to thrusting during the Cenozoic era. However, the exact timing of the shift remainsan issue to be refined. In this study, we conducted LA-ICP-MS based apatite fission trackdating at massifs of both the hanging wall and footwall along the NAF, to shed light on datingthe thrusting-related exhumation of the NAF. The results show that the hanging wall massifsof the NAF present a quasi-isothermal quiescence during the early Cenozoic, followedby a rapid cooling phase with mean cooling rate of 6.66 ± 0.72 ˚ C / Ma since∼15 Ma, resulting from accelerated exhumation which has been interpreted tomark intense vertical uplift of the NAF. Significantly younger age (∼5 Ma) buthigher rate (15.33 ± 2.10 ˚ C / Ma) of rapid-cooling event occurred at the footwallcompared to the hanging wall suggests a northward propagation of thrusting into theinterior Tarim basin. Combining previous studies, we attribute the structural shift ofthe NAF from along-strike slipping to thrusting to the Mid-Miocene kinematicreorganization of the ATFs, supporting to the two-stage evolution model of theAFTs that: (1) during ∼50-15 Ma, the NAF acted as a part of the Altyn Tagh faultexperiencing along-strike slipping, with the Altun Shan elevated north within bigrestraining-double-bends; and (2) after ∼15 Ma, the Altyn Tagh fault cut through thedouble-bends with significant thrusting along the NAF, circumscribing the presenttriangle-shaped Altun Shan featured with uplifting south beginning at ∼15 Ma. [ABSTRACT FROM AUTHOR]

[Display omitted] • Onset time of the basin was the late Miocene to early Pliocene (∼5.8–4.6 Ma). • Multiple depocenters existed in the basin and intergraded to one in the Quaternary. • Eastward migration of the depocenter records the collision between the Pamir and South Tian Shan. The Pamir salient is the preeminent example of an intracontinental collision and defines the western end of the Himalayan-Tibetan orogen. Previous work has paid much attention to reveal the internal evolution of the Plateau. However, the structural growth and expansion of the Northern Pamir still have several unknowns. To address this process of the indentation, we describe the architecture of the Wupoer Piggyback Basin (WPB), the westernmost tip of the Tarim Basin, in between the northeastern Main Pamir Thrust (MPT), and the Pamir Frontal Thrust (PFT). The geometry of the WPB growth strata and its relationship with the compressive structures were explored through six seismic sections, five cutting the WPB along dip and one along strike. According to the sense prevailing in the literature, we define the onset of a piggyback basin with the first evidence of tectonic deformation within the basin fill. Interpreted from the seismic sections and field work, an unconformity between the Atushi Fm. and the underlying strata marks the base of the WPB, dated the onset of the basin at the latest Miocene to early Pliocene (∼5.8–4.5 Ma). The growth strata were separated into 6 units above the unconformity (G1-G6). The relative isopach maps reveal the existence of three main depocenters, evolving to a single one in the Quaternary. The structural interpretation documents the PFT is significantly segmented by transfer faults and lateral ramps. The eastward migration of the depocenter since the Quaternary points to the oblique collision between the Pamir and the South Tian Shan and gradual encroachment of deformation towards the east. [ABSTRACT FROM AUTHOR]

The geology of Tian Shan provides an excellent example for understanding the intracontinental orogeny in the context of Indian–Eurasian convergence. Previous studies leave much space in basinfill deposition process to be assessed in the regions west to the Talas–Fergana fault (TFF). We improve the understanding by conducting new investigations on sedimentology and magnetostratigraphy in the Tierekesazi section of the foreland region of south West Tian Shan. Four lithofacies have been identified, (i) marine lithofacies from the Aertashi to Bashibulake Formations, (ii) lacustrine to fluvial (plain) lithofacies from the Keziluoyi to the middle Pakabulake Formations, (iii) alluvial sand–gravel sheet lithofacies in the upper Pakabulake Formation, and (iv) conglomerate lithofacies from the Atushi to Xiyu Formations. Magnetostratigraphic analysis, accompanied with biostratigraphic correlation, indicates that four lithofacies cover age intervals of ca. 65 Ma to 34 Ma, ca. 22.1 Ma to 12 Ma, 12 Ma to 5.2 Ma, and 5.2 Ma to approximately present (?), with the sediment accumulation rates increasing from ca. 2.4/3.3–3.5 (compacted/decompacted) cm/ka in the lithofacies (i), to 12.3/16–17 cm/ka in the lithofacies (ii), to 16.3/19.5–20.6 cm/ka in the lithofacies (iii), and finally to > 22.8/> 22.8 cm/ka in the lithofacies (iv). These results suggest three episodes of sedimentary events. Combined with previous results, these episodes of sedimentary events are attributed to tectonic activities that are widespread along south Tian Shan. We speculate that the Oligo-Miocene boundary event more directly and likely marks the initial underthrusting of the Tarim block beneath the south Tian Shan. The mid-Miocene and Mio-Pliocene boundary events, although approximately synchronous between the regions east and west to the TFF, have different structural expressions in the two regions. Such difference is proposed to cause the dextral slipping of the TFF, and more fundamentally, likely be driven by the northward indentation of the Pamir at this time. [ABSTRACT FROM AUTHOR]

The intracontinental response to plate-boundary and mantle processes, such as subduction or continental collisions, is an important topic in the Earth Sciences. Cretaceous to Cenozoic extension across East China is related to the interaction between the Asian continental lithosphere and western Pacific oceanic subduction system, and the associated intra-plate structures and basins provide robust temporal and spatial records of regional continental deformation. Although extension may primarily be driven by slab rollback and/or back-arc opening, mid-ocean-ridge subduction may have played a significant role in this process. To explore how the western Pacific subduction system impacts intracontinental deformation across East China, we use onshore-offshore geological records, geophysical survey observations, and time-dependent Pacific plate models to document the temporal and spatial variation of continental deformation in the Lower Yangtze region adjacent to the Yellow Sea. Based on our compilation, we argue that mantle-wedge convection, with coupled subduction of the trench-parallel Izanagi (Paleo-Pacific)-Pacific mid-ocean ridge, exerts a first-order control on extensional deformation in East China. Beneath eastern China, the mantle wedge history consists of two phases: (1) initial development of the mantle wedge as the Cretaceous Izanagi slab transitioned from flat-slab to steep subduction; and (2) mature mantle wedge convection during Cenozoic subduction of the Pacific plate. Relatively steep subduction of the progressively younging Izanagi plate during the Late Cretaceous-Paleocene resulted in strong mantle convection and coupled upper plate extension in eastern China. The collision of the Izanagi-Pacific plate ridge system with the trench resulted in a magmatic gap and short-lived uplift of eastern China. Following this, subduction of the rapidly aging Pacific plate resulted in a larger, but relatively weaker, mantle convection cell that drove weaker upper plate extension. The vigor of wedge mantle convection was modulated by the age of the Pacific subducting slab, which directly influenced the formation and evolution of intracontinental extension and sedimentary basins across eastern China. The pre-existing Triassic Tan-Lu fault zone has reactivated since the Late Eocene (ca. 40 Ma) due to westward subduction of the Pacific slab to partition strain between extensional dextral faulting in the Bohai Bay and Lower Yangtze basins, thereby diversifying Cenozoic lithospheric extensional deformation in eastern China. Several major Cenozoic extensional basins spatially correlate with the Triassic Sulu orogenic belt, which we interpret to suggest that these basins are underlain by the older and fragmented orogenic basement that acted as mechanically weak zones for localized high-magnitude extension. We present a comprehensive tectonic model that relates intracontinental deformation to subduction zone dynamics, particularly emphasizing the importance of the age of the subducting slab, thus providing a coherent geologic process to explain the deformation kinematics in eastern China and the diversity of observed Mesozoic-Cenozoic basin formation. [ABSTRACT FROM AUTHOR]