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A set of nearly NS-trending rifts developed in the Himalayan orogen and southern Tibet, which are the large-scale extensional structures formed under the continuous compression of the Indo-Eurasia continent, playing a significant role in revealing the post-collisional evolution of the Tibetan Plateau. Different predictions have been made on the spatiotemporal distribution of these rifts through the existing hypothesis models, constituting the key factors constraining the formation system of the rifts. In this study we synthesized previous studies on the initiation time of rifting, and further clarified the spatiotemporal trend. The analysis results showed that the rifting initiated progressively earlier westward, which is consistent with the evolution of post-collisional magmatism in the Lhasa Terrain. Moreover, combined with the geophysical observations, it is inferred that the geodynamic mechanism of the nearly NS-trending rifts accords closely with the hypothesis model concerning the eastward-propagating lateral detachment of the subducted Indian slab. The Indian slab detachment resulted in asynchronous gravitational potential energy gradients, which drove the lithosphere flow eastward and eventually caused the eastward development of the rifting.

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 northern margin of the Tibetan Plateau is defined by the left‐lateral Altyn Tagh fault. It remains unclear whether the Cenozoic deformation related to the India‐Asia collision has remained stationary along the Altyn Tagh fault or propagated northward into the southeastern Tarim Basin. The Cenozoic Cherchen fault is located in the southeastern Tarim Basin, ∼90–120 km north of the Altyn Tagh fault, and thus, may play a critical role in addressing this issue. Here, we used a densely‐spaced two‐dimensional seismic reflection survey to investigate the geometry and kinematics of the Cherchen fault and understand its role in the expansion of the northern margin of the Tibetan Plateau. Our seismic study shows that the Cenozoic Cherchen fault is a high‐angle left‐lateral transpressional fault. Kinematic analysis of the Cherchen fault suggests that a restraining bend structure has formed along its central segment. Stratigraphic records suggest that the Cherchen fault initiated in the Paleozoic and reactivated during the middle Miocene (ca. 17–15.7 Ma). We infer that the dip‐slip and strike‐slip rates of the Cherchen fault are ∼0.09 mm/a and ∼1.66 mm/a, respectively. A regional cross section reveals that the northward expansion of the plateau is ongoing, but the range is limited to ∼90–120 km. We interpret that middle Miocene tectonic activity throughout the region was also concentrated along the northern plateau margin, defined by both northeast‐directed crustal shortening and northward expansion of the plateau. Key Points: The Tibetan Plateau is propagating north of the Altyn Tagh fault into the Tarim Basin, evidenced by slip along the Cherchen faultStructural analysis of the Cherchen fault suggests it is a high‐angle transpressional faultThe northward expansion of the Tibetan Plateau is ongoing but limited to ∼90–120 km [ABSTRACT FROM AUTHOR]

In an orogen‐foreland basin system, syn‐orogenic sedimentation and deformation records within the foreland basin provide critical evidence for understanding uplift and erosion processes of adjacent orogenic belts. Foreland fold‐and‐thrust belts (FTBs) are widely developed around the Tian Shan range, Central Asia. Problem of how crustal shortening accumulates and propagates from the Tian Shan to adjacent foreland basins is essential for understanding the overall dynamics of Tian Shan. In this study, we interpreted three high‐resolution seismic reflection profiles to estimate the magnitude and distribution of Cenozoic shortening across the Eastern Kuqa FTB, South Tian Shan foreland. Combined with well‐dated syntectonic stratigraphy, we further evaluate the timing, rate, and migration of the deformation front of the Kuqa FTB. Our results suggest that the Kuqa FTB's total crustal shortening increases westward. The distribution of crustal shortening across secondary structural belts shows a gradual, basinward decrease, which can be explained by the telescoped mechanism. Propagation rates of the Kuqa FTB's deformation front indicate an episodic propagation of the foreland thrust wedge, with an acceleration after ∼12 Ma. Similar episodic propagation pattern has also been observed in other foreland FTBs around the Tian Shan, but they show significant spatio‐temporal variations in the propagation stages and related rates. Plain Language Summary: The Tian Shan range stretches over 2,500 km from east to west and is one of the Earth's largest intracontinental orogenic belts. As the mountains grew, deformation propagated into foreland basins around the range, forming a series of fold‐and‐thrust belts (FTBs). To better understand the spatial distribution of crustal shortening, and basinward propagation process in foreland FTBs, we interpret and reconstruct three high‐resolution seismic profiles across the Eastern Kuqa FTB, South Tian Shan. Our study indicates that the total crustal shortening of the Eastern Kuqa FTB increases westward. Within the Kuqa FTB, a telescoped distribution pattern of crustal shortening is also observed in frontal thin‐skinned structures above the regional salt décollements. In addition, we find that the basinward propagation of Kuqa FTB is episodic, which is featured by a two‐stage evolution pattern. Key Points: The Eastern Kuqa fold‐and‐thrust belt shows a westerly increase in total shortening and a telescoped pattern in shortening distributionThe Cenozoic propagation of the Kuqa thrust belt indicates an episodic process that accelerated after ∼12 MaBasinward growth of the Tian Shan orogenic wedge varies spatiotemporally; propagation stages and rates vary in different foreland basins [ABSTRACT FROM AUTHOR]

A key issue in the Cenozoic evolution of the Tibetan plateau is the geodynamic drivers for north‐trending rifting in southern Tibet. Recent studies have demonstrated an eastward propagation pattern for rift initiation, but the along‐strike variations remain poorly resolved. Two models that predict different north‐south rift kinematics include northward underthrusting or southward tearing of the Indian lithospheric slab, predicting a northward or southward propagation trend of individual rifts along strike, respectively. The Yadong‐Gulu rift (YGR) is an ideal case to investigate this issue due to its long strike length (∼500 km) and location above proposed slab‐tear structures. Here, we compile constraints on both rift initiation and acceleration, and report new apatite fission track and (U‐Th)/He thermochronological data along the southern segment of YGR. Our main findings are as follows. First, the rifts west of the YGR initiated simultaneously along strike, which we suggest is at odds with predictions of either slab‐tear or slab‐underthrusting models. However, most of these rifts show a northward younging pattern in rift acceleration, which may be governed by low‐angle Indian slab underthrusting released by slab tearing. Second, the initiation timing of the Yadong rift is constrained at ∼13–11 Ma. Combined with published constraints along strike, we demonstrate a clear northward propagation in rift initiation along the YGR. This kinematic pattern may be affected by its orientation of the most oblique northeast‐trending among all rift systems or the outward expansion of the Himalayan arc. Plain Language Summary: The Himalayan‐Tibetan orogen is undergoing active east‐west extension under the continuous compression of the colliding Indo‐Eurasia continents. This extension is manifested by a series of northward oriented (north‐striking) rifts in southern Tibet, the geodynamics of which is critical in revealing the Cenozoic evolution of the Tibetan Plateau. Despite the importance, their development pattern along strike has not been well understood, leaving the mechanisms that emphasize their along‐strike propagation poorly tested, such as the southward slab tearing and northward slab underthrusting models. They predict a southward or northward propagation of rifting along strike, respectively. Therefore, the along‐strike propagation process of individual rifts constitutes the key factor in distinguishing the two mechanisms. In this study, we adopted thermochronological techniques to constrain the propagation of the Yadong‐Gulu rift (YGR) that has the longest strike length. The results suggest that the YGR youngs northward, which is contrary to the situations of each rift system to its west that initiated nearly coevally along strike. This implies that the onset of north‐trending rifts should not be significantly affected by geodynamic process in N‐S direction through either slab tearing or underthrusting, while the northward younging trend of YGR is controlled largely by its oblique striking. Key Points: Initiation timing of Yadong‐Gulu rift youngs northward (Yadong at ∼13–11 Ma), but each rift system to its west initiated nearly coevally along strikeSlab tearing released subducting slab and activated slab underthrusting that causes northward rifting accelerationExtraordinary earlier initiation of the Yadong rift was related to its most oblique NE‐trending or outward expansion of the Himalayan arc [ABSTRACT FROM AUTHOR]

The Cenozoic North Altyn Fault (NAF) is a major splay of the Altyn Tagh Fault along the northwestern margin of the Tibetan Plateau, but its role in the development of this plateau margin in response to the India‐Eurasia collision is highly debated. Here, we investigate fault geometry, kinematics, and shortening magnitude along the westernmost 120 km of the NAF. Seismic surveys reveal minimal Cenozoic shortening in the subsurface of the Southeast Tarim Basin and support for large‐scale (>120 km) left slip on the NAF. Based on the satellite imagery, two new faults are identified to define the northern boundary of the NAF system, which together with the NAF to the south constitute a narrow transpressional shear zone comprised of three basement‐cored, fault‐bound slivers. Fission track data and thermal modeling indicate that the NAF zone experienced broad reburial during early Cenozoic that was locally interrupted by ∼40 to 35 Ma exhumation proximal to the NAF, followed by widespread but heterogeneous exhumation since ∼17 to 15 Ma associated with ∼9 to 11 km of total shortening across the NAF system via thick‐skinned faulting. We conclude that the NAF initiated as a left‐slip fault at ∼40 to 35 Ma and then became transpressional at ∼17 to 15 Ma during the middle‐Miocene reorganization of the Altyn Tagh Fault system. We find no evidence to support prior inferences of large‐scale (∼100 km) underthrusting of the Tarim Basin beneath the Tibetan Plateau along the NAF. Plain Language Summary: The Cenozoic rise of the Tibetan Plateau has exerted a significant impact on the global climate and migration of Asian hominin. To reveal the growth history of the plateau, geologists rack their brains to learn how the plateau‐bounding faults have evolved in time. Here, we investigate the Cenozoic evolution of the North Altyn Fault (NAF) in the northwestern edge of the Tibetan Plateau, which generates 2–4 km topographic relief between the high plateau and low‐land Tarim Basin. Based on seismic survey, satellite imaging, and geological dating, we find that the NAF initiated with left‐lateral slip at ∼40 to 35 Ma but switched to a transpressional fault accommodating both left‐lateral and dip slips since ∼17 to 15 Ma. Our data show only 9–11 km of shortening across the NAF, which contradicts the prior view that the Tibetan Plateau was thrust over the Tarim Basin by ∼100 km. This study provides independent evidence supporting the reorganization of the Altyn Tagh Fault system at ∼17 to 15 Ma and indicates that the present‐day tectonic and topographic configurations in the northern Tibetan Plateau have developed since the middle Miocene. Key Points: The North Altyn Fault (NAF) is a transpressional shear zone comprised of narrow fault slivers and has absorbed ∼9 to 11 km of Cenozoic shorteningExtensive early Cenozoic burial was locally interrupted by ∼40 to 35 Ma exhumation, implying onset of left slip on the NAFWidespread and heterogeneous exhumation since ∼17 to 15 Ma manifests a transition from left slip to transpression on the NAF [ABSTRACT FROM AUTHOR]

The Altyn Tagh Fault (ATF) serves as a key continental‐scale controlling structural element of the Tibetan Plateau. However, its eastward extent remains controversial. Here we use high‐resolution seismic reflection profiles to investigate the subsurface structures of the easternmost ATF and use these to delimit the easternmost extent of the fault. The structural analyses show an eastward geometric change from transpressional positive flower structures to compressional thrusts, with transpression‐induced shortening magnitudes decreasing eastwards from a maximum of ~5.3 km to being absent. Stratigraphic controls indicate that the deformation took place over the last ~<1.2 Ma. Our wider findings lead us to: (a) reject the suggestion that the ATF previously extended beyond the Kuantan Shan‐Hei Shan to link with the Alxa‐East Mongolia Fault; and (b) propose that the rigid block model used to describe the Tibetan Plateau crust is not consistent with the extent and structural details of the easternmost ATF. [ABSTRACT FROM AUTHOR]

Abstract: Bending‐moment faults and flexural‐slip faults (FSFs), as two basic fault styles due to bending‐related tangential longitudinal strain, extensively and prominently crop out as surface scarps in the Pamir‐western Kunlun and southern Tian Shan regions, northwestern China. Characteristic geomorphic expression, favorable formation conditions, and the role in folding accommodation of active FSFs have been systematically summarized in our recent studies. Here we investigate similar properties for well‐developed bending‐moment normal fault (BMnF) scarps at four sites. Our study concludes the following: (i) BMnF scarps are relatively sinuous compared to FSF scarps and probably trend obliquely to the fold hinge. A group of BMnF scarps can delineate a single asymmetric graben or create grabens alternating with horsts. (ii) BMnF scarps primarily overlie poorly‐layered conglomerates. The fold's interlimb angle can range from ~160° to <40°, and the folding kinematics can vary from active‐hinge migration to fixed‐hinge rotation. (iii) The fault‐zone width, fault spacing, and efficiency in folding accommodation significantly decrease with (a) thinner conglomerate beds, (b) a smaller interlimb angle, and (c) the transition of the hinge from migrated to fixed. (iv) Different bed lithologies and fold geometries beneath the surface account for the predominance of BMnF scarps on the western Kunlun piedmont and FSF scarps in the Pamir‐Tian Shan convergent zone. (v) Presence of BMnF scarps on the western Kunlun piedmont indicates that ~4 km of fault slip is transferred northward along a detachment at the base of the Cenozoic and is ultimately absorbed by the Mazatagh Thrust in the Tarim Basin. [ABSTRACT FROM AUTHOR]

Palaeo-uplifts often exist in fold-and-thrust belts. However, their effects on the deformational process have not yet been well understood. To evaluate such effects, six analogue models were systematically run based on geological features of the Wupoer fold-and-thrust belt (FTB), NE Pamir, where the Wulagen palaeo-uplift with overlying gypsum bed has been clearly identified. Our analogue results demonstrated that the palaeo-uplift (its location and inhomogenous distribution), accompanied with overlying gypsum bed that serves as ductile décollement, plays a critical role in localizing the front thrust fault and shaping it into arc form. The results indicate that the front thrust fault slides along the ductile décollement (gypsum bed), and breaks through onto the surface at the region where the palaeo-uplift develops, forming a piggy-back basin in the hanging wall. It suggests that the palaeo-uplift with consequent topographic variation of the overlying ductile décollement localizes the breakthrough point of the front thrust fault. In addition, the results indicate that the front thrust fault (Pamir Front Thrust, PFT) initially broke through in the location where it develops the Wulagen palaeo-uplift and propagated aside. This resulted in the distance between the PFT and the basement-involved fault (Main Pamir Thrust, MPT) to decrease from the region with palaeo-uplift to the areas aside without palaeo-uplift, thereby forming the arc-shaped PFT in map view. The results of this study also provide a revised geological model, which emphasizes the effect of décollement layer on absorbing the slip along the PFT. Our results provide a new mechanical interpretation of the deformation of Wupoer FTB, NE Pamir. [ABSTRACT FROM AUTHOR]

Objective To introduce a modified model for quantitative testing of glucose microleakage by constant air pressure and evaluate the sealing ability of four root canal sealers including AH Plus, Roeko Seal, Cortisomol and RC Sealer. Methods Fifty-six straight maxillary anterior teeth were randomly divided into four experimental groups with 12 samples in each group, group A: AH Plus, group B: Roeko Seal, group C: Cortisomol, group D: RC Sealer, and positive and negative control group with 4 samples in each. After regular root preparation, samples in experimental groups were obturated by cold gutta-percha lateral compaction technique with sealers according to group description. Control groups were obturated with cold gutta-percha only. Through the model above, the value of glucose microleakage from crown to root was measured at 1, 3, 5, 7, 10, 15, 20, 25, 30 days with the glucose oxidase-peroxidase method (GOD-POD). Results At day 1, 3, 5, no significant difference of microleakage was found between group A and B (GOD-POD). The same result was also seen between group C and D. From 7 days, microleakage value in each experimental group gradually increased, and statistical difference was found between groups (P<0.05). Conclusion This new model using constant air pressure is easy to establish, sensitive and practical. Among all the sealers evaluated, polydimethylsiloxane based root canal sealer, Roeko Seal has the greatest sealing ability, while epoxy-amine resin based AH Plus is second and Zinc Oxide based Cortisomol and RC Sealer have the least sealing ability. [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]

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]

• Cona rift is the easternmost rift in the Himalayas. • Multi-thermochronometers suggest 3.0–2.3 Ma rift initiation. • Initiation of Himalayan rifts youngs monotonically eastward. • Lithospheric flow driven by asynchronous GPE gradients caused E–W extension. Several competing hypotheses have been proposed to explain east-west extension observed across the Himalayan orogen, based primarily on observations from the western and central Himalaya. They make predictions for the temporal and spatial patterns of deformation in the eastern Himalaya. These tectonic models include radial spreading or oroclinal bending of the Himalayan arc, oblique convergence of the Indian continent, tearing or lateral detachment of the Indian slab and eastward flow of lithosphere. Here, for the first time we constrain the activity history of the Cona rift, the only north-trending rift currently recognized in the eastern Himalaya, based on biotite and K-feldspar 40Ar/39Ar and zircon and apatite (U–Th)/He thermochronology, to evaluate these proposed rifting mechanisms. Low-temperature thermochronological results suggest that the Cona rift is the youngest rift system in the Himalayas: after a slow phase of exhumation since ∼14 Ma (∼0.2–0.13 mm/yr), normal faulting initiated here at ∼3.0–2.3 Ma with a fault slip rate of ∼3.8–1.6 mm/yr and a horizontal extension magnitude of ∼2–5 km. Analysis of rifting across the Himalayas shows that rift initiation ages young eastward, which is matched by eastward decreasing rift-extension magnitudes. Monotonically eastward younging rift development is consistent with the tectonic model involving eastward lithospheric flow driven by Indian slab dynamics and coupled asynchronous gravitational potential energy gradients. [ABSTRACT FROM AUTHOR]

Ubiquitin-specific protease 31 (USP31) is a member of deubiquitinase family that is involved in nuclear factor-κB activation and sarcomagenesis. However, little is known about posttranslational modification in the regulation of its activity and cervical cancer cell growth. In our study, we found that the Lys1264 residue of USP31 can be modified with an acetyl group by high-resolution mass spectrometry in HeLa cell line, and site-specific mutagenesis can significantly increase USP31 ubiquitin hydrolase activity and decrease the expression of p65. When being transfected with a plasmid expressing mutated USP31, the number of cancer cells was significantly decreased. We also observed that mutated USP31 could promote apoptosis but not cell cycle by flow cytometer analysis. Overexpression of mutated USP31 could reverse the effect in USP31 knockdown cell line. To further investigate its activity in tumorigenesis, deacetylase sirtuin 1 (Sirt1) was shown to interact with USP31 by co-immunoprecipitation and blocking the function of Sirt1 by knockdown or the inhibitor nicotinamide could increase the acetylation of USP31. When Lys1264 of USP31 mutated, Sirt1 could not remove its acetylation and alter the expression level of p65. Finally, inhibition or knockdown of Sirt1 suppressed USP31 activity in HeLa cell line, leading to cisplatin-induced apoptosis resistance. Therefore, acetylation at Lys1264 suppresses USP31 activity and plays a protective role in cancer cell growth. Our study contributes to understanding the mechanism of USP31 activity regulation and its role in tumorigenesis., (© The Author(s) 2021. Published by Oxford University Press on behalf of the Center for Excellence in Molecular Cell Science, Chinese Academy of Sciences. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)