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In order to study the behavior and characteristics of crowd evacuation in buildings, and then organize crowd evacuation reasonably and efficiently in emergency, a simulation model of crowd evacuation in buildings is proposed, which not only accords with reality, but also comprehensively considers many factors. Aiming at the shortcomings of the crowd evacuation simulation model in the existing building emergency evacuation, this model provides a multi-agent evacuation simulation method and system based on panic emotion, which aims to more truly simulate the crowd evacuation process in emergency, and has important practical significance for the crowd evacuation plan in emergency and how to effectively organize crowd evacuation and reduce casualties in emergencies. In order to achieve the above goal, a multi-agent evacuation simulation method based on leaders and panic emotions is proposed. The method includes the following three stages: perception stage, decision-making stage and action stage, and each stage is explained step by step.

Combining detrital zircon (DZ) U-Pb age and Lu-Hf isotope data is important in revealing the tectonic evolution of ancient orogens. Here, we conducted DZ U-Pb and Lu-Hf isotope research on 7 modern river sand samples collected from the northern Chinese West Tianshan Orogen (CWTO). The DZs from modern river sands yield ages 340 to 320 Ma and reflect Mesozoic magmatism in the northern Yili Block (YB). In addition, the DZs reflected disproportionate contributions from the source area, which might be affected by the zircon fertility and erodibility of the source rocks. These newly obtained data, together with compiled DZ U-Pb and Lu-Hf isotope data from other modern river sands and ancient sedimentary rocks in the CWTO, are used to constrain the subduction and closure history of the southwestern part of the Paleo-Asian Ocean. The eHf(t) values of 500 to 450 Ma zircons from the southern YB and Central Tianshan Block display a fanning trend (changing from a narrow to a wide range over time), indicating a crustal thickening event at ∼ 450 Ma. The closure of the North Tianshan Ocean was completed when the YB and an immature/nascent island arc collided in the latest Carboniferous. The South Tianshan Ocean (STO) subducted bidirectionally beneath the Yili–Central Tianshan Block (YCTB) and the Tarim Craton starting at 460 Ma. Slab rollback or retreat of the STO in the northern Tarim Craton starting at 440 Ma caused the opening of several small diachronous back-arc basins. The fanning trend of eHf(t) values indicates that collision between the YCTB and the Tarim Craton occurred at 320 to 310 Ma.

We demonstrate two synthetic single-cell systems that can be used to better understand how the acquisition of an orphan gene can affect complex phenotypes. The Arabidopsis orphan gene, Qua-Quine Starch (QQS) has been identified as a regulator of carbon (C) and nitrogen (N) partitioning across multiple plant species. QQS modulates this important biotechnological trait by replacing NF-YB (Nuclear Factor Y, subunit B) in its interaction with NF-YC. In this study, we expand on these prior findings by developing Chlamydomonas reinhardtii and Saccharomyces cerevisiae strains, to refactor the functional interactions between QQS and NF-Y subunits to affect modulations in C and N allocation. Expression of QQS in C. reinhardtii modulates C (i.e., starch) and N (i.e., protein) allocation by affecting interactions between NF-YC and NF-YB subunits. Studies in S. cerevisiae revealed similar functional interactions between QQS and the NF-YC homolog (HAP5), modulating C (i.e., glycogen) and N (i.e., protein) allocation. However, in S. cerevisiae both the NF-YA (HAP2) and NF-YB (HAP3) homologs appear to have redundant functions to enable QQS and HAP5 to affect C and N allocation. The genetically tractable systems that developed herein exhibit the plasticity to modulate highly complex phenotypes.

The Lincang-Inthanon tectonic belt is a major tectonic boundary within the southeastern Tibetan Plateau and Indo-China Peninsula, which are typical examples of tectonic extrusion in SE Asia. The Lincang strain zone, Lancang-Gengma fault, and Inthanon metamorphic complex make up this nearly N–S-striking tectonic belt, which separates the Baoshan–Shan Thai and Simao-Indochina terranes. New petrographic, structural, and mica 40Ar/39Ar geochronological studies were conducted to reveal their deformation styles and constrain the timing of their tectonic evolution. W–E-directed compression related to the subduction of the Paleotethyan Ocean with subsequent continental collision and sinistral ductile shearing in the early Oligocene are recorded along the Lincang strain zone. The Lancang-Gengma fault zone switched from sinistral shearing to dextral motion in the late Cenozoic and shows a deformation history similar to that of the parallel Red River fault. The Inthanon metamorphic complex may have experienced crustal shortening in the early Cenozoic, followed by sinistral transtension in the early Miocene. The Lincang-Inthanon tectonic belt shows many lithological, tectonic evolutionary, and metamorphic similarities with the Gaoligong, Chongshan, and Ailaoshan–Red River shear zones. Therefore, the sinistral shearing along the Lincang-Inthanon tectonic belt and the Chongshan shear zone in the north, which may have initiated since the early Oligocene, played an important role in adjusting differential extrusion and rotation of the Baoshan–Shan Thai and Simao-Indochina terranes. Our results delineate the regional tectonic framework and provide insights into the characteristics and geodynamics of intracontinental deformation in the eastern India-Eurasia oblique convergence zone.

During the collision of India and Eurasia, regional-scale strike-slip shear zones played a key role in accommodating lateral extrusion of blocks, block rotation, and vertical exhumation of metamorphic rocks as presented by deformation on the Ailao Shan-Red River shear zone (ARSZ) in the Eastern Himalayan Syntaxis region and western Yunnan, China. We report structural, mica Ar/Ar, apatite fission-track (AFT), and apatite (U-Th)/He (AHe) data from the Diancangshan massif in the middle segment of the ARSZ. These structural data reveal that the massif forms a region-scale antiform, bordered by two branches of the ARSZ along its eastern and western margins. Structural evidence for partial melting in the horizontal mylonites in the gneiss core document that the gneiss experienced a horizontal shear deformation in the middle crust. Muscovite Ar/Ar ages of 36–29 Ma from the core represent cooling ages. Muscovite Ar/Ar ages of 25 and 17 Ma from greenschist-facies mylonites along the western and southern shear zones, respectively, are interpreted as recording deformation in the ARSZ. The AFT ages, ranging from 15 to 5 Ma, represent a quiescent gap with a slow cooling/exhumation in the massif. AHe results suggest that a rapid cooling and final exhumation episode of the massif could have started before 3.2 Ma, or likely ca. 5 Ma, and continue to the present. The high-temperature horizontal shearing layers of the core were first formed across the Indochina Block, locally antiformed along the tectonic boundaries, and then cooled through the mica Ar-Ar closure temperature during Eocene or early Oligocene, subsequently reworked and further exhumed by sinistral strike-slip movement along the ARSZ during the early Oligocene (ca. 29 Ma), lasting until ca. 17 Ma, then final exhumation of the massif occurred by dextral normal faulting on the Weixi-Qiaohou and Red River faults along the limbs of the ARSZ since ca. 5 Ma. The formation of the antiform could indicate local crustal thickening in an early transpressional setting corresponding to India-Asia convergence. Large-scale sinistral ductile shear along the ARSZ in the shallow crust accommodated lateral extrusion of the Indochina Block, and further contributed to the vertical exhumation of the metamorphic massif from the late Oligocene to the middle Miocene. Furthermore, the change of kinematic reversal and associated cooling episodes along the ARSZ since the middle Miocene or early Pliocene imply a tectonic transfer from strain localization along the major tectonic boundaries to continuous deformation corresponding to plateau growth and expansion.

The tectonic affinities of the microcontinents in the eastern Central Asian Orogenic Belt of NE China, particularly the Jiamusi Block, have been hotly debated in the last decade. The Mashan Complex...

The Himalayan Orogen is a typical continental collision orogenic belt that formed during India-Asia collision. The orogeny involved a transition in tectonic regime, which led to E-W–trending extension during the middle Miocene. At the same time, widespread post-collisional adakitic magmatism occurred in southern Tibet, particularly in the Lhasa Terrane, and these rocks provide a valuable record of the collisional geodynamic processes within the lithosphere. Few studies have focused on the middle Miocene adakitic rocks of the Himalayan Orogen, so further research is required to constrain their origin and geodynamics. This study presents new geochronological and geochemical data, including the whole rock Sr-Nd and zircon Hf isotopic compositions from the Mayum pluton in the Mayum-Gong Tso area, Northern Himalaya. Zircon U-Pb ages show that the Mayum granodiorite porphyries crystallized at 16.67 ± 0.14 Ma (mean square weighted deviation [MSWD] = 0.82, n = 29) and 16.68 ± 0.16 Ma (MSWD = 1.13, n = 28), indicating that they formed during the middle Miocene. The major and trace element characteristics are as follows: SiO2 = 65.79–67.31 wt%, Al2O3 = 15.28–16.00 wt%, MgO = 1.77–1.89 wt%, Y = 12.0–13.5 ppm, Yb = 0.11–0.99 ppm, Sr = 719–822 ppm, (La/Yb)N = 21.89–27.02, Sr/Y = 56.1–65.5, and the rocks have weak negative Eu anomalies (Eu/Eu* = 0.76–0.85), indicating that they are adakitic rocks and show high Sr-Ba granite affinity. The Mayum granodiorite porphyries have high K2O contents (3.42–3.65 wt%), Na2O (3.76–4.04 wt%), and K2O/Na2O ratios of 0.91–0.95, indicating a high-K calc-alkaline affinity. All samples are enriched in large-ion lithophile elements and depleted in high field strength elements. The initial 87Sr/86Sr ratios are 0.709262–0.709327 and εNd(t) values are −6.36 to −7.07, which correspond to two-stage Nd model ages [TDM2(Nd)] of 1405–1348 Ma. In situ zircon Lu-Hf isotopic compositions are variable, with 176Hf/177Hf ratios of 0.2823845–0.282824, εHf(t) values of −13.37 to +2.17, and two-stage Hf model ages [TDM2(Hf)] of 1704–841 Ma. These geochemical and Sr-Nd-Hf isotopic characteristics indicate that the Mayum granodiorite porphyries may be derived from partial melting of the subducted Indian thickened ancient mafic lower crust (∼92%) mixed with depleted mid-ocean ridge basalt mantle material input (∼8%) slightly. Crust-mantle interaction was induced by asthenospheric upwelling followed by the underplating of the Himalayan lower crust beneath Southern Tibet during the middle Miocene in response to significant changes in the geodynamics of the India-Asia collisional orogen. These deep geodynamic processes reflect the break-off or rollback of the subducted Indian continental slab, which caused asthenospheric upwelling, the input of juvenile heat, and the addition of depleted mantle material. This study indicates that the middle Miocene Himalayan adakitic rocks, which include the Miocene Yardoi two-mica granite, Gyangzê granite porphyry dike, Bendui two-mica granite, Langkazi enclave, Kuday dacitic dike, Lasa pluton, and Mayum pluton, form a belt of adakitic rocks in the Northern Himalaya to the south of the Indus-Tsangpo Suture Zone. These adakitic rocks have similar temporal and spatial distributions, geochemical features, and Sr-Nd isotopic compositions, indicating that their petrogenesis and geodynamic settings were similar. At that time there was widespread initiation of N-S–trending rifting, exhumation of central Himalayan eclogites, and large changes in the compositions of Himalayan leucogranites in the Himalayan Orogen. These can be attributed to significant changes in the characteristics of the subducted Indian continental lithosphere during the middle Miocene. The middle Miocene Himalayan adakitic rocks provide valuable insights into this transition in the tectonic regime and deep geodynamic processes.

Non-intrusive load monitoring (NILM) can obtain fine-grained electricity consumption information of each appliance by analyzing the voltage and current data measured at a single point on the bus, which is of great significance for promoting and improving the efficiency and sustainability of the power grid and enhancing the energy efficiency of users. NILM mainly includes data collection and preprocessing, event detection, feature extraction, and appliance identification. One of the most critical steps in NILM is signature extraction, which is the basis for all algorithms to achieve good state detection and energy disaggregation. With the generalization of machine learning algorithms, different algorithms have also been used to extract unique signatures of appliances. Recently, the development and deployment of the voltage–current (V-I) trajectory signatures applied for appliance identification motivated us to present a comprehensive review in this domain. The V-I trajectory signatures have the potential to be an intermediate domain between computer vision and NILM. By identifying the V-I trajectory, we can detect the operating state of the appliance. We also summarize existing papers based on V-I trajectories and look forward to future research directions that help to promote the field’s development.

The Central Asian Orogenic Belt (CAOB), also known as the Altaids, is one of the world's largest accretionary orogen and it is estimated that ca. 50% of the present crust in Central Asia is juvenile. However, some researchers argued that the amount of continental growth in the CAOB was overestimated. One evidence is that many intra-arc sediments and accretionary wedges in the CAOB contain heterogeneous sources (large proportion of detritus from basement rocks), and no examples from the CAOB where the sediment mainly derived from erosion of juvenile crust has been reported. Here, we conducted geochemistry and Nd isotope study on the turbidites from the North Tianshan Accretionary Complex (NTAC) in the Chinese West Tianshan orogen, which might be an good example of sediment derived from juvenile materials. The turbiditess in the NTAC are mainly composed of fine-grained sandstone, siltstone and argillaceous siliceous rocks. In the southern part near the North Tianshan Fault, the turbidites were deformed and metamorphosed into slate. Geochemically, all the collected rocks (sandstoen/siltstone and slates) have relatively low CIA (Chemical Index of Alteration) values (35 to 63) and PIA (plagioclase index of alteration ) values (34 to 68), indicating that their source rocks experienced relatively weak weathering before erosion and deposition. Both the sandstone/siltstone and slate samples display high ICV (Index of Compositional Variability) values of 0.89 to 1.50 and 0.89 to 0.93, higher than the PAAS, suggesting a relatively immature source. Based on geochemical data, it is suggested that the sandstone/siltstone were mainly derived from intermediate and felsic igneous rocks, while the slates were mainly derived from felsic igneous rocks, and their source rocks were most likely formed in oceanic/continental arc settings. Most of the samples from the NTAC display high positive εNd(t) values (+5.5 to +7.9) with only one exception of +0.8, and the Nd model ages (cluster between 672 Ma and 522 Ma, with one exception of 1.1 Ga) are only slightly older than their depositional age (Carboniferous). Our previous study has revealed that the detrital zircons from the turbidites display unimodal age patterns with peaks at 320 to 310 Ma, and have high positive εHf(t) values (+2.9 to +15.8, mostly greater than +10). These results indicate that the turbidites in the NTAC were mainly derived from intermediate to felsic igneous rocks with juvenile arc signature. The northern Chinese West Tianshan is a typical site with significant Phanerozoic continental growth, and the mechanism needs further study.

Postcollisional adakitic magmatism in the Himalayan Orogen provides a probe into the evolution of the collisional orogen. During the Miocene, the Himalayan Orogen underwent a tectonic transition, which was characterized by a series of tectonic events, including the activity of the North-South Trending Rift, exhumation of eclogite, rapid uplift of the orogen, and the extensive adakitic rocks. In this study, we reported the geochemistry and geochronological data of the Kuday dikes intruding into the Tethys Himalayan Sequence near the Sakya Dome of southern Tibet. The Kuday dikes are granitoid porphyries with zircon U-Pb ages of ca. 11 Ma. The Kuday granitoid porphyry dikes have high SiO2 (63.01–68.41 wt.%) and Al2O3 (17.31–19.87 wt.%) but low Mg (0.88–1.41 wt.%), Mg# (36–50), Ni (2.8–19.3 ppm), and Cr (2.9–26.4 ppm), indicating no input of mantle material. They have high Sr (934–1881 ppm), (La/Yb)N (18.84–113.13), and Sr/Y ratios (89.25–305.85) but low K2O/Na2O ratios (0.17–0.79), indicating that they are adakitic affinity. They display initial 87Sr/86Sr ratios of 0.707–0.711 and εNdt values of -3.7–-6.7. These geochemical signatures indicate that the Kuday granitoid porphyrite dikes were derived from the partial melting of the thickened lower crust of the Himalayan Orogen. Partial melting of the thickened lower crust requires additional heat, so the delamination model with lithospheric mantle thinning and asthenospheric upwelling is proposed to explain the formation of the Kuday adakitic rock. The delamination model can also provide a reasonable explanation for the tectonic events during the Miocene in the Himalayan Orogen.

The complex evolutionary history of collision-related suture zones in the western Qiangtang is poorly understood, due to the lack of pivotal magmatic and tectonic records. The Chem Co intermediate-felsic batholith is situated in the westernmost section of Qiangtang, where it intruded into the Upper Paleozoic metamorphic sedimentary series and was cut by Late-Cenozoic active normal faults. Here, we present evidence from field observations, geochemistry, zircon U Pb and Hf isotopes, and mica 40Ar 39Ar analysis of these granitoid rocks. Zircon U Pb ages ranging from 107.3 ± 1.4 to 123.7 ± 1.7 Ma reveal that this magmatism initiated in the Early Cretaceous. Mica 40Ar 39Ar yield plateau ages from 99 to 118 Ma suggest rapid emplacement into the cold crust without disturbance by subsequent >320 °C tectono-thermal events. Major element geochemistry shows these granitic rocks are enriched in Al, depleted in Ca, lie mostly within the high–K calc–alkaline series and have peraluminous features. Mineral modes that lack amphibole but contain muscovite, together with the geochemical characteristics, indicate an S–type granite affinity. Furthermore, the rocks are strongly enriched in large-ion lithophile elements (LILE) and light rare earth elements (LREE), and are moderately to strongly depleted in high field strength elements (HFSE) and heavy rare earth elements (HREE), thus indicating typical characteristics of arc-related magmatic rocks. Considering the petrogenesis, geochemical features, zircon U Pb ages, negative zircon eHf(t) values, similarity with the southwestern Qiangtang intrusions, and the geological setting, we conclude that the Chem Co granite was derived from the anatexis of crustal lithosphere through a “soft” collision associated with the continuing northwards subduction of the Bangong–Nujiang Tethyan (BNT) Ocean. We propose that the final closure and termination of the western segment of the BNT Ocean was completed later than 107 Ma.

The eastern Heilongjiang Province, NE China, is located in the eastern CAOB (Central Asian Orogenic Belt). Previous studies suggest that subduction of the Mudanjiang and Paleo-Pacific oceans had been initiated in this area during the early Mesozoic. However, research on the Mesozoic volcanic rocks is insufficient, limiting our understanding of the relationship between magmatism and subduction process. To solve the problem, seven volcanic rocks in the Lesser Xing'an-Zhangguangcai Range and the Jiamusi Block were collected for zircon U-Pb dating (SHRIMP) and whole-rock geochemical analysis. Most samples from the Lesser Xing'an-Zhangguangcai Range are Jurassic in age (189-178 Ma), including andesite, trachyandesite, trachydacite, and rhyolite. The andesitic to trachytic rocks were generated by magma mixing at an active continental margin, whereas the rhyolite is highly fractionated I-type. All the samples from the Jiamusi Block and one basaltic andesite from the Lesser Xing'an Range are late Early Cretaceous in age (ca. 100 Ma) and were formed in a back-arc extensional setting (roll-back). Fractional crystallization was important in the generation of most Cretaceous rocks (basalt to trachydacite). However, magma mixing or crustal contamination was required to explain some andesites from the Jiamusi Block showing extremely low Cr, Ni, and Mg#. When integrated with the coeval blueschist-facies metamorphism, the Early Jurassic volcanism indicates an active continental margin in the Lesser Xing'an-Zhangguangcai Range due to the westward subduction of the Mudanjiang Ocean. After the closure of the Mudanjiang Ocean, two NE/NNE trending sinistral strike-slip faults in NE China were triggered, accompanied by the slab roll-back of the Paleo-Pacific oceanic plate. The Jurassic continental arc and accretionary complexes in NE China were cut through by the two strike-slip faults and bended to form small oroclines. At ca. 100 Ma, numerous accretionary complexes were accreted along the eastern margin of the CAOB, further forcing the retreat of trench and slab roll-back. The late Early Cretaceous intra-continental volcanism was generated in the Lesser Xing'an-Zhangguangcai Range and Jiamusi Block during this roll-back process.

Early Jurassic granitoids are widespread in the Lesser Xing’an–Zhangguangcai Ranges, providing excellent targets to understand the late Paleozoic to early Mesozoic tectonic framework and evolution of Northeast China, especially the Jiamusi block and its related structural belts. In this paper, we present new geochronological, geochemical, and isotopic data from the granitoids in the Lesser Xing’an–Zhangguangcai Ranges to constrain the early Mesozoic tectonic evolution of the Mudanjiang Ocean between the Jiamusi and Songnen blocks. Our results show that the granitic intrusions in the Lesser Xing’an–Zhangguangcai Ranges are mainly composed of syenogranite, monzogranite, granodiorite, and tonalite, which have crystallization ages from 196 to 181 Ma. Their geochemical features indicate that these Jurassic intrusions are all high-K calc-alkaline I-type granites with metaluminous to weakly peraluminous compositions. These granitoids are characterized by enrichments in large ion lithophile elements (e.g., Ba, Th, U) and light rare earth elements and depletions in high field strength elements (e.g., Nb and Ta) and heavy rare earth elements, which are typical for continental arc–type granites. The sources of these granitoids were likely derived from juvenile Mesoproterozoic to Neoproterozoic crustal materials (e.g., metabasaltic rocks). Integrated with data from regional coeval magmatism, metamorphism, metallogeny, and structure, our new data suggest that the granitoids in the Lesser Xing’an–Zhangguangcai Ranges were probably formed in an active continental margin setting, which fits well in our previous model of Early Jurassic westward subduction of the Mudanjiang Ocean between the Jiamusi and Songnen blocks.

International audience

Electrochemical surface-enhanced Raman scattering measurements of single layer graphene provide unique information on resonant excitation induced by localized surface plasmons under controlled electron or hole doping. The highly confined electromagnetic field from the LSPs of the Au nanodimer structures prepared on defect-free graphene can generate holes and electrons of the electrochemical potentials beyond the limit of far-field light illumination. The electrochemical in situ SERS spectra prove nonzero wavevector excitation through the observation of normally forbidden Raman bands in graphene. The present findings point to a novel approach to breaking the limit of optoelectronic interactions and photochemical reactions of graphene and other semiconductors.

The most striking structural features in the interior of the Shan Plateau, southeast of the eastern Himalayan syntaxis, are a series of NE-trending faults that exhibit sinistral movement and an arcuate geometry. Their origin and tectonic evolution remain poorly understood. Furthermore, a switch in slip sense is recorded along many of these faults, but the timing of kinematic reversal is still unclear, hindering an understanding of the causal geodynamic mechanisms. We conducted an integrative study of apatite and zircon (U-Th)/He thermochronology, 40Ar/39Ar geochronology, and structural and geomorphic analysis to decipher the evolution of two major NE-trending faults: the Nantinghe and Dayingjiang faults. At least three deformation stages are identified within the Nantinghe fault zone, including top-to-the-SE/ESE thrusting, dextral ductile strike-slip shearing, and sinistral movement. Zircon and apatite (U-Th)/He data, collected from the northeastern terminus of the Nantinghe fault, reveal rapid cooling in the early Miocene. Combined with the 40Ar/39Ar data from sinistrally sheared mylonite, left-lateral movement on the Nantinghe fault is inferred to have initiated as early as ca. 20 Ma. The Dayingjiang fault reactivated as a sinistral brittle fault along the dextral Yingjiang shear zone. A two-stage thermal history is identified along the shear zone, with prominent cooling during dextral ductile shearing in the early- to mid-Miocene followed by a lower-magnitude cooling episode at ca. 11 Ma caused by sinistral transtension along the Dayingjiang fault. The evolution of the Nantinghe and Dayingjiang faults suggests that the NE-trending fault system in the Shan Plateau may have developed along preexisting structures and underwent diachronous slip-sense inversion in the late Cenozoic. The northward advance of the eastern Himalayan syntaxis caused a major change in both the regional stress field and fault geometries in the eastern India-Eurasia oblique convergence zone, contributing to the inversion of fault kinematics.

The surface enhanced-Raman spectroscopy (SERS) of the graphene was measured using Au nanodimers prepared by angle-resolved nanosphere lithography and 785 nm laser with increasing power. It is found that the ratio between D band and 2D band changes with laser power. The change is attributed to the effect of localized surface plasmon (LSP), which causes the restructuring of Au nanodimers and oxidation of graphene. We established the method to characterize the formation of the defects in graphene using SERS.

The Cona-Oiga rift (COR) is the easternmost member of a series of ∼N-S trending Cenozoic rifts in the southern Tibetan Plateau. The Yarlung River flows from west to east, across the COR and exhibits diverse river morphology along strike. We analyze tributary fluvial longitudinal profiles in the Yarlung drainage and the published strain rate field on both sides of the rift in order to gain knowledge about its development and crustal deformation patterns within the plateau interior. Tributaries on the western side of the rift have relatively low normalized steepness index (ksn). Concave curves in χ-elevation plots and cross-divide contrasts in χ, mean relief, and mean gradient, indicate ongoing river reorganization in this region. In contrast, high topographic relief and steep stream channels developed on the eastern side. In addition, spatial variations in negative dilatational strain rates indicate diverse crustal shortening and regional uplift across the COR. We suggest that the Cona-Oiga rift plays an important role in accommodating deformation associated with the continuing indentation of the eastern Himalayan syntaxis. Tectonic forcing might be the dominant factor controlling landscape evolution across the COR.

International audience; The high‐pressure Heilongjiang Complex belongs to a Jurassic accretionary complex in Yilan area, NE China. The complex is located in the junction of three orogenic systems in the NE Asia: the E‐W‐striking Central Asian Orogenic Belt (CAOB), the N‐S‐striking Paleo‐Pacific system, and the ENE‐WSW‐striking Mongol‐Okhotsk system. Thus, a detailed tectono‐metamorphic analysis coupled with accurate radiometric dating of the Heilongjiang Complex provided in this study represent important evidence for understanding the complex interactions between the three orogenic systems in the Late‐Palaeozoic to Mesozoic. New structural and microstructural data combined with the strain analysis highlight the presence of three distinct deformation events affecting the high‐pressure Heilongjiang Complex. The first deformation event D1 is related to development of blueschist facies prolate to plane strain fabrics that were subsequently reworked by the blueschist‐amphibolite facies event D2 that transposed all previous structures by the main west‐dipping schistosity. This planar fabric was folded by upright F3 folds and heterogeneously reworked by greenschist facies E‐W‐striking vertical cleavage during large scale N‐S shortening. Each deformation event was related to specific strain fabrics and metamorphic conditions highlighting dynamic evolution of the subduction complex during burial, exhumation, and final shortening. The first D1 event is related to westward directed prograde constrictional flow and progressive dismembering of competent mafic, ultramafic layers, and quartzites in highly stretched meta‐sedimentary matrix. This mélange was folded by recumbent detachment folds resulting in emplacement of the exhumed unit progressively reaching amphibolite facies conditions atop of W‐WSW‐dipping channel. This event is associated with dominant flattening implying increasing mechanical coupling between the colliding Songliao and Jiamusi blocks. Subsequently, the accreted subduction complex was reworked during N‐S‐directed horizontal shortening. This event was associated with an important post‐buckle flattening of fold limbs and rotation of competent blocks with inherited D1 and D2 strain ellipsoids along F3 fold axes. Our new 40Ar‐39Ar plateau ages on muscovite and phengite (173–177 Ma), together with previous radiometric data, are interpreted as reflecting exhumation of subduction channel during the blueschist‐amphibolite facies event while the N‐S shortening (D3) probably operated in Late Jurassic as indicated by some previously published cooling ages (~140–160 Ma). The westward‐oriented subduction and exhumation fabrics of the high‐pressure Heilongjiang accretionary complex followed by N‐S‐directed upright folding are interpreted to reflect transition from E‐W Pacific subduction regime to N‐S‐directed shortening related to the closure of the Mongol‐Okhotsk Ocean.

The Xianshuihe fault in eastern Tibet is one of the most active faults in China, with the next large earthquake most likely to occur along its SE part near Kangding. Quantifying its slip rate along...

Continental-scale shear zones play an important role in accommodating block extrusion and rotation as shown by deformation on the Ailaoshan-Red River shear zone (ASRRSZ) in the SE Tibetan Plateau. This study presents 13 apatite (U-Th)/He, 11 zircon (U-Th)/He, and three apatite fission track dates, together with thermal modeling in the Ailaoshan and Xuelongshan segments (ALSZ and XLSZ) of the shear zone to investigate its Cenozoic exhumation history and mechanism, which are critical for understanding its tectonic and landscape evolution. Our results, combined with published chronologic data, reveal that shear zone rocks along the ALSZ experienced prominent and rapid cooling from high temperature (>500°C) to 120–60°C at a rate of 75–100°C/Myr during 29–17 Ma with northwestward younging onset. A second, lower magnitude accelerated cooling occurred at 14–10 Ma along the ALSZ at a rate of 20–30°C/Myr, with a later initiation on the XLSZ at ~5 Ma and continuing to present with a cooling rate of ~20°C/Myr. Thermal modeling reveals a single rapid cooling phase with a rate of 17–14°C/Myr in the Eocene to early Oligocene for samples outside the shear zones. These three fast cooling episodes are directly related to deformation stages including crustal shortening across the SE plateau, sinistral ductile shearing along the ASRRSZ, and dextral faulting with a dip-slip component on the Red River and Weixi-Qiaohou faults along the shear zone flanks. Furthermore, the northward migration of kinematic reversal and associated cooling along strike since the mid-late Miocene likely reflects the northward advance of the eastern Himalayan syntaxis.

Table S1: Bulk element geochemistry and isotopic composition of the Mayum pluton; Table S2: Zircon LA-ICP-MS U-Pb data for the Mayum pluton; Table S3: Zircon in situ Lu-Hf isotopic data for the Mayum pluton; Table S4: Data statistics for Himalayan Eocene and Miocene adakitic rocks.

NE China recorded the key tectonic evolution history of the Eurasian Plate from the Paleozoic-Mesozoiccollisional formation of the Central Asian Orogenic Belt to the Mesozoic subduction of the Paleo-Pacific Ocean.To better understand this tectonic transition, it is crucial to constrain the time and pattern of the initial subduc-tion of the Paleo-Pacific Ocean. Recently, someresearchers proposed that theMudanjiang Ocean existed betweenthe Songnen and Jiamusi blockswas part of the Paleo-Pacific Ocean. Here, through geochemical and geochrono-logical studies on the widespread granitoids in the Lesser Xing'an-Zhangguangcai Range in the eastern SongnenBlock, we verify that these magmatic rocks show volcanic arc affinity with increased mantle contribution fromeast to thewest of the range, likely related to a flattening subduction of theMudanjiang Ocean. In addition, a uni-versal westward younging trend for over 70 Myr can be observed for the granitoids throughout the LesserXing'an-ZhangguangcaiRange, indicating a long-lastingsubductionof theMudanjiangOcean.More interestingly,the oldest ages of the granitoids in the east display a northward younging trend from275Ma to 218Ma, suggest-ing that the subduction of the Mudanjiang Ocean had been initiated at latest by 275 Ma in the south and thenprogressively expanded to the north. Based on these observations, we proposed a new tectonic evolutionmodel for theMudanjiang Ocean, i.e., a Triassic-Jurassicwestward scissor-like subduction and closure, to contrib-ute to the understanding of the early subduction of the Paleo-PacificOcean

Three continent-scale shear zones are arguably the most outstanding structural features in the southeastern Tibetan Plateau, and therefore, their tectonic and landscape evolution have significant implications for understanding the history and mechanisms of intracontinental mountain building and plateau growth. This study presents low-temperature thermochronology from the Gaoligong and Chongshan shear zones (GLSZ and CSSZ) and quantitative analyses of fluvial longitudinal profiles of tributaries in the Salween drainage, which lies between the shear zones. Apatite and zircon (U-Th)/He data reveal a two-stage exhumation history for both shear zones: rapid and prominent cooling in the middle Miocene followed by a second, lower magnitude cooling event in the late Miocene to early Pliocene. Ductile transpressional shearing is inferred to have caused the first cooling, continuing until ~11 Ma. The northward migration of the tectonic events along the Mogok metamorphic belt and GLSZ and synchronous dextral displacement along the Jiali fault indicate the dominant role of the north advancing eastern Himalayan syntaxis on the surrounding structures. Increased river incision is identified in the middle Salween drainage, leading to two-segment river profiles and further exhumation along the GLSZ and CSSZ. The tributary transient response could result from temporal changes in uplift or adjustments of the trunk channel to climatic change. Furthermore, glaciers play an important role in shaping the landscape of the upper reaches of catchments in the northern segment of the shear zones. Different drivers for the two exhumation events may reflect distinct stages of plateau growth characterized by different crustal deformation patterns.

We conducted an integrated study including U-Pb dating and Lu-Hf isotope analysis for detrital zircons from the turbidites of the North Tianshan Accretionary Complex, northern Chinese West Tianshan, to constrain their depositional age, source characteristics and tectonic setting. Almost all the detrital zircons display well developed oscillatory zoning textures and have high Th/U ratios, reflecting an igneous origin. Based on the analytical results, the depositional ages of the four samples were 303 Ma–312 Ma, 310 Ma and 321 Ma. The studied samples all display unimodal detrital zircon spectra, with few Precambrian zircons, coinciding with the age spectra of sediments deposited in convergent basins, most likely a forearc basin. Most of the zircons and other mineral grains have euhedral to subhedral shapes, reflecting a relatively short transportation distance. Considering the occurrence of volcanic lithic fragments in thin-sections of the sandstones, we propose that the northern edge of Yili Block, which is widely accepted as a Paleozoic continental arc formed by subduction of the North Tianshan Ocean, was the most likely source area for the North Tianshan turbidites. There are 137 Lu-Hf isotope analyses on zircons with concordant U-Pb ages, all showing positive eHf(t) values (eHf(t) = +2.9–+15.8), and young TCDM ages (328–1152 Ma, peak at 400–800 Ma). The Hf isotope characteristics indicate important growth of juvenile crust and minor crustal contamination during the formation of the zircons’ host rocks. When we examine the Hf isotope of reported magmatic rocks from the northern Yili Block, we found an increasing trend of eHf(t) values from the Early Paleozoic to Late Paleozoic. This indicates that there was a large amount of juvenile material extracted from the depleted mantle in the Carboniferous. Taking into account of previous research, we conclude that the northern West Tianshan was a subduction-arc system during the Carboniferous, and the studied turbidites from the North Tianshan Accretionary Complex were sourced from the magmatic arc of the northern Yili Block and most likely deposited in a fore-arc basin in the Late Carboniferous.

The closure of the North Tianshan Ocean between the Junggar Terrane and the Yili Block is a longtime debated issue in literature, because of the different understanding of the Carboniferous volcanic rocks in the northern margin of the Yili Block. This study presents new geochronological and whole-rock geochemical data for the granitic rocks from the Borohoro pluton to provide constraints on the tectonic regime for the northern West Tianshan during the Carboniferous. LA-ICP-MS U-Pb dating results reveal two magmatic phases for the Borohoro pluton. The former magmatic activity in the Early Carboniferous formed the fine-grained granodiorite (332 Ma). The later magmatic activity occurred during the Late Carboniferous (305–300 Ma), forming a diversity of granitic rocks, involving quartz diorite, granodiorite and granite. Geochemical and mineralogical studies reveal that the studied granitic rocks from the Borohoro pluton all belong to metaluminous to weakly peraluminous, calc-alkaline I-type granites. They are characterized by enrichment in LILEs relative to HFSEs, and depletion of Nb, Ti and P, typical of continental arc-type granites. The intermediate SiO2, high Al2O3, and relatively low Fe2O3T, MgO and TiO2 contents reflect that these granitic rocks are mainly crust-derived. But the high Mg# values for most samples and the occurrence of microgranular mafic enclaves indicate that their magma sources were mixed by mantle-derived components. Especially, the Late Carboniferous rocks define an elegant mixing trend in both the Rb-Rb/V and the 1/V-Rb/V diagrams, consistent with mixing between magmas from subcontinental lithospheric mantle and mafic lower crust. Taking into consideration of the facts that all the Devonian to Carboniferous granitoids belong to calc-alkaline I-type granites, and granitoids of A-type didn’t appear until the Early Permian, we suggest that the subduction of the North Tianshan Ocean continued to the Late Carboniferous, generating the granitic rocks of the Borohoro pluton.