40 results on '"Wang, Qingchen"'
Search Results
2. ASTRO: An AST-Assisted Approach for Generalizable Neural Clone Detection
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Zhang, Yifan, Yang, Junwen, Dong, Haoyu, Wang, Qingchen, Shao, Huajie, Leach, Kevin, and Huang, Yu
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Software Engineering (cs.SE) ,FOS: Computer and information sciences ,Computer Science - Software Engineering ,Computer Science - Machine Learning ,Machine Learning (cs.LG) - Abstract
Neural clone detection has attracted the attention of software engineering researchers and practitioners. However, most neural clone detection methods do not generalize beyond the scope of clones that appear in the training dataset. This results in poor model performance, especially in terms of model recall. In this paper, we present an Abstract Syntax Tree (AST) assisted approach for generalizable neural clone detection, or ASTRO, a framework for finding clones in codebases reflecting industry practices. We present three main components: (1) an AST-inspired representation for source code that leverages program structure and semantics, (2) a global graph representation that captures the context of an AST among a corpus of programs, and (3) a graph embedding for programs that, in combination with extant large-scale language models, improves state-of-the-art code clone detection. Our experimental results show that ASTRO improves state-of-the-art neural clone detection approaches in both recall and F-1 scores.
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- 2022
3. Improved Electrogeometric Model of UHV Transmission Line Based on Long Gap Discharge and Its Application
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Hu, Yuanchao, Yang, Minghao, Qu, Lu, An, Yunzhu, Wang, Jing, Cheng, Yan, Sha, Xiao, Wang, Qingchen, Ma, Chenghui, An, Bingchen, and Chen, Dan
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Economics and Econometrics ,Fuel Technology ,Renewable Energy, Sustainability and the Environment ,Energy Engineering and Power Technology - Abstract
Based on long air gap discharge test data and lightning return stroke observation data, an improved electrogeometric model (EGM) considering terrain conditions is established and verified to analyze the lightning shielding performance of UHV transmission lines. The striking distance formula is modified as rs = 0.13 (I2 + 40I)0.814. In this paper, the lightning shielding failure rate of three-phase conductors of EHV and UHV transmission lines calculated by the improved EGM model is consistent with the lightning observation data of actual transmission lines in Japan and the scaled lightning discharge simulation experimental results of UHV transmission lines in plains and mountainous areas of China, which verifies the applicability of the improved EGM model to evaluate the lightning shielding performance of large-scale UHV transmission lines. The improved EGM model is applied to evaluate the influence of tower type and slope steepness on the shielding failure tripping rate of UHV transmission lines. The shielding failure tripping rate of the SZ322 tower is higher than that of the SZT1 tower, and the shielding failure tripping rate of UHV transmission lines is greatly affected by slope gradient and increases with the increase of slope gradient.
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- 2022
4. Verifiable RFID Location Privacy Scheme Based on NIZK
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Wang Qingchen, Chen Yuan, and Tang Hongyu
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- 2021
5. Value of Information in Networked Control Systems Subject to Delay
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Siyi Wang, Qingchen Liu, Precious Ugo Abara, John S. Baras and Sandra Hirche
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ddc - Published
- 2020
6. Mesozoic Crustal Thickening of the Longmenshan Belt (NE Tibet, China) by Imbrication of Basement Slices: Insights From Structural Analysis, Petrofabric and Magnetic Fabric Studies, and Gravity Modeling
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Xue, Zhenhua, Martelet, Guillaume, Lin, Wei, Faure, Michel, Chen, Yan, Wei, Wei, Li, Shuangjian, Wang, Qingchen, State Key Laboratory of Lithospheric Evolution (SKL), Institute of Geology and Geophysics [Beijing] (IGG), Chinese Academy of Sciences [Beijing] (CAS)-Chinese Academy of Sciences [Beijing] (CAS), Institut des Sciences de la Terre d'Orléans - UMR7327 (ISTO), Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Bureau de Recherches Géologiques et Minières (BRGM) (BRGM), Géodynamique - UMR7327, Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Bureau de Recherches Géologiques et Minières (BRGM) (BRGM)-Institut des Sciences de la Terre d'Orléans - UMR7327 (ISTO), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Bureau de Recherches Géologiques et Minières (BRGM) (BRGM)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Observatoire de Paris, Bureau de Recherches Géologiques et Minières (BRGM) (BRGM), and Institute of Petroleum Exploration and Development
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[SDU.STU.TE]Sciences of the Universe [physics]/Earth Sciences/Tectonics ,Longmenshan thrust belt ,intracontinental deformation ,[SDU.STU.GP]Sciences of the Universe [physics]/Earth Sciences/Geophysics [physics.geo-ph] ,Tibetan Plateau ,thick-skinned structure - Abstract
International audience; This work first presents field structural analysis, anisotropy of magnetic susceptibility (AMS) measurements, and kinematic and microstructural studies on the Neoproterozoic Pengguan complex located in the middle segment of the Longmenshan thrust belt (LMTB), NE Tibet. These investigations indicate that the Pengguan complex is a heterogeneous unit with a ductilely deformed NW domain and an undeformed SE domain, rather than a single homogeneous body as previously thought. The NW part of the Pengguan complex is constrained by top-to-the-NW shearing along its NW boundary and top-to-theSE shearing along its SE boundary, where it imbricates and overrides the SE domain. Two orogen-perpendicular gravity models not only support the imbricated shape of the Pengguan complex but also reveal an imbrication of high-density material hidden below the Paleozoic rocks on the west of the LMTB. Regionally, this suggests a basement-slice-imbricated structure that developed along the margin of the Yangtze Block, as shown by the regional gravity anomaly map, together with the published nearby seismic profile and the distribution of orogen-parallel Neoproterozoic complexes. Integrating the previously published ages of the NW normal faulting and of the SE directed thrusting, the locally fast exhumation rate, and the lithological characteristics of the sediments in the LMTB front, we interpret the basement-slice-imbricated structure as the result of southeastward thrusting of the basement slices during the Late Jurassic-Early Cretaceous. This architecture makes a significant contribution to the crustal thickening of the LMTB during the Mesozoic, and therefore, the Cenozoic thickening of the Longmenshan belt might be less important than often suggested.
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- 2017
7. Continuity of the Alpine slab unraveled by high-resolution P-wave tomography
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Maierová, P., Schulmann, K., Lexa, O., ŠtÍpskÁ, P., Janoušek, V., Čadek, O., Zhao, Liang, Paul, Anne, Malusà, Marco, Xu, Xiaobing, Zheng, Tianyu, Solarino, Stefano, Guillot, Stéphane, Schwartz, Stéphane, Dumont, Thierry, Salimbeni, Simone, Aubert, Coralie, Pondrelli, Silvia, Wang, Qingchen, Zhu, Rixiang, Czech Geological Survey [Praha], Institut de physique du globe de Strasbourg (IPGS), Université de Strasbourg (UNISTRA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Institute of Petrology and Structural geology, Charles University [Prague], Ecole et Observatoire des Sciences de la Terre (EOST), Tianjin University (TJU), Laboratoire de Géophysique Interne et Tectonophysique (LGIT), Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes (UGA)-Laboratoire Central des Ponts et Chaussées (LCPC)-Institut des Sciences de la Terre (ISTerre), Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-PRES Université de Grenoble-Institut de recherche pour le développement [IRD] : UR219-Institut national des sciences de l'Univers (INSU - CNRS)-Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR)-Université Joseph Fourier - Grenoble 1 (UJF)-Centre National de la Recherche Scientifique (CNRS)-PRES Université de Grenoble-Institut de recherche pour le développement [IRD] : UR219-Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR), University of Milano - Bicocca, Laboratoire d'Electronique et Electromagnétisme (L2E), Sorbonne Université (SU), Institut des Sciences de la Terre (ISTerre), Université Grenoble Alpes (UGA)-Centre National de la Recherche Scientifique (CNRS)-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-PRES Université de Grenoble-Institut de recherche pour le développement [IRD] : UR219-Institut national des sciences de l'Univers (INSU - CNRS)-Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR)-Université Joseph Fourier - Grenoble 1 (UJF), Institut Camille Jordan [Villeurbanne] (ICJ), École Centrale de Lyon (ECL), Université de Lyon-Université de Lyon-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Université Jean Monnet [Saint-Étienne] (UJM)-Centre National de la Recherche Scientifique (CNRS), Istituto Nazionale di Geofisica e Vulcanologia - Sezione di Bologna (INGV), Istituto Nazionale di Geofisica e Vulcanologia, Institute of Geology and Geophysics [Beijing] (IGG), Chinese Academy of Sciences [Beijing] (CAS), Department of Earth and Planetary Sciences [Kobe], and Kobe University
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[SDU.STU.TE]Sciences of the Universe [physics]/Earth Sciences/Tectonics ,[SDU]Sciences of the Universe [physics] ,[SDU.STU]Sciences of the Universe [physics]/Earth Sciences ,ComputingMilieux_MISCELLANEOUS - Abstract
International audience
- Published
- 2016
8. Detrital zircon U-Pb ages and Hf isotopic constraints on the terrigenous sediments of the Western Alps and their paleogeographic implications
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Chu, Yang, Lin, Wei, Faure, Michel, Wang, Qingchen, State Key Laboratory of Lithospheric Evolution (SKL), Institute of Geology and Geophysics [Beijing] (IGG), Chinese Academy of Sciences [Beijing] (CAS)-Chinese Academy of Sciences [Beijing] (CAS), Institut des Sciences de la Terre d'Orléans - UMR7327 (ISTO), Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Bureau de Recherches Géologiques et Minières (BRGM) (BRGM), Géodynamique - UMR7327, Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Bureau de Recherches Géologiques et Minières (BRGM) (BRGM)-Institut des Sciences de la Terre d'Orléans - UMR7327 (ISTO), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Bureau de Recherches Géologiques et Minières (BRGM) (BRGM)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Observatoire de Paris, and 'Strategic Priority Research Program (B)' of the Chinese Academy of Sciences (XDB03010801), the State Key Laboratory of Lithospheric Evolution, China, the National Natural Science Foundation of China (41273070, 41350001 and 41302161)
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[SDU.STU.TE]Sciences of the Universe [physics]/Earth Sciences/Tectonics - Abstract
International audience; Detrital zircons from Cretaceous micaschist, Late Eocene-Earliest Oligocene sandstone and Early Oligocene siltstone of the Western Alps fall into three main separable age clusters at 610-540 Ma, 490-430 Ma, and 340-280 Ma that correspond to the Cadomian (Neoproterozoic), Ordovician and Variscan (Carboniferous) events widespread in Western and Central Europe. Hf isotopic results indicate that these three magmatic and tectonic episodes did not give rise to significant production of juvenile crust. A distinguishable group of Triassic zircons, around 250-200 Ma which is considered to derive from the Southern Alps, has been detected in the Early Oligocene "Schistes à Blocs" formation and the Brianconnais “Flysch Noir”. In contrast, this age group is absent in Late Eocene-Earliest Oligocene sandstones. In agreement with sedimentological studies, our results show that the main source areas of the Eocene sandstone were probably located in the European continent. The arrival of detritus from the Internal Zone occurred in Early Oligocene, coeval with the tectonic rotation from northwestward to westward in the propagation of allochthonous units. Based on previous studies and our new data, we argue that the the Brianconnais Zone was likely a paleorelief since the Middle Eocene that accounts for the lack of detritus from the Adriatic units. Contemporary sediments were accumulated in the foredeep of the Adriatic Plate. From Oligocene time onwards, the blockage was cut through after a regional uplifting, and thus the Internal Zone started to provide detritus into the western flexural basins.
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- 2016
9. Continuity of the Alpine slab unraveled by high-resolution P wave tomography
- Author
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Zhao, Liang, Paul, Anne, Malusà, Marco, Xu, Xiaobing, Zheng, Tianyu, Solarino, Stefano, Guillot, Stéphane, Schwartz, Stéphane, Dumont, Thierry, Salimbeni, Simone, Aubert, Coralie, Pondrelli, Silvia, Wang, Qingchen, Zhu, Rixiang, Zhao, L, Paul, A, Malusa', M, Xu, X, Zheng, T, Solarino, S, Guillot, S, Schwartz, S, Dumont, T, Salimbeni, S, Aubert, C, Pondrelli, S, Wang, Q, Zhu, R, Institute of Geology and Geophysics [Beijing] (IGG), Chinese Academy of Sciences [Beijing] (CAS), Institut des Sciences de la Terre (ISTerre), Institut Français des Sciences et Technologies des Transports, de l'Aménagement et des Réseaux (IFSTTAR)-Institut national des sciences de l'Univers (INSU - CNRS)-Institut de recherche pour le développement [IRD] : UR219-Université Savoie Mont Blanc (USMB [Université de Savoie] [Université de Chambéry])-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), Università degli Studi di Milano-Bicocca [Milano] (UNIMIB), Istituto Nazionale di Geofisica e Vulcanologia - Sezione di Bologna (INGV), Istituto Nazionale di Geofisica e Vulcanologia, ANR-10-LABX-0056,OSUG@2020,Innovative strategies for observing and modelling natural systems(2010), and Università degli Studi di Milano-Bicocca = University of Milano-Bicocca (UNIMIB)
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[SDU.STU.GP]Sciences of the Universe [physics]/Earth Sciences/Geophysics [physics.geo-ph] ,Adriatic slab ,slab breakoff ,Alpine slab ,P-wave tomography ,finite frequency ,Tethyan convergence - Abstract
International audience; The question of lateral and/or vertical continuity of subducted slabs in active orogens is a hot topic partly due to poorly resolved tomographic data. The complex slab structure beneath the Alpine region is only partly resolved by available geophysical data, leaving many geological and geodynamical issues widely open. Based upon a finite-frequency kernel method, we present a new high-resolution tomography model using P wave data from 527 broadband seismic stations, both from permanent networks and temporary experiments. This model provides an improved image of the slab structure in the Alpine region and fundamental pinpoints for the analysis of Cenozoic magmatism, (U)HP metamorphism, and Alpine topography. Our results document the lateral continuity of the European slab from the Western Alps to the central Alps, and the downdip slab continuity beneath the central Alps, ruling out the hypothesis of slab break off to explain Cenozoic Alpine magmatism. A low-velocity anomaly is observed in the upper mantle beneath the core of the Western Alps, pointing to dynamic topography effects. A NE dipping Adriatic slab, consistent with Dinaric subduction, is possibly observed beneath the Eastern Alps, whereas the laterally continuous Adriatic slab of the Northern Apennines shows major gaps at the boundary with the Southern Apennines and becomes near vertical in the Alps-Apennines transition zone. Tear faults accommodating opposite-dipping subductions during Alpine convergence may represent reactivated lithospheric faults inherited from Tethyan extension. Our results suggest that the interpretations of previous tomography results that include successive slab break offs along the Alpine-Zagros-Himalaya orogenic belt might be proficiently reconsidered.
- Published
- 2016
10. Environmental Redox Changes of the Ancient Sea in the Yangtze Area during the Ordo-Silurian Transition
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Chu Yang, Chen Daizhao, Wang Jian-guo, Wang Qingchen, and Yan Detian
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chemistry.chemical_classification ,Total organic carbon ,Geochemistry ,Halocline ,Geology ,engineering.material ,Anoxic waters ,Sedimentary depositional environment ,Oceanography ,Water column ,chemistry ,engineering ,Organic matter ,Pyrite ,Sea level - Abstract
Extensive organic-matter (OM) rich facies (black shales) occur in the Ordo-Silurian boundary successions in the Yangtze area, South China. To investigate the redox changes of the Yangtze Sea during the Ordo-Silurian transition, two OM sections (Wangjiawan in Yichang, Hubei Province, and Sanjiaguan in Zhangjiajie, Hunan Province) straddling the Ordo-Silurian boundary are studied. The measurements finished in this study include contents of the total organic carbon (TOC), pyrite sulphur, and different species of Fe, including dithionite-extractable Fe (FeD), pyrite Fe (FeP), HCI-extractable Fe (FeH), and total Fe (FeT), in black shales, as well as other redox proxies, such as the S/C ratio, the ratio between highly reactive Fe (FeHR = FeD + FeP) and FeT, and the Fep/(FeP + FeH) ratio, known as the degree of pyritization (DOP). In the Wangjiawan section, the Middle Ashgill sediments have high FeHR/FeT ratios (0.20-0.77; avg. 0.45), high DOP values (0.21-0.72; avg. 0.54), and a relatively constant sulfur content independent of the organic carbon content. By the contrast, the mid-early Hirnantian deposits generally have low FeHR/FeT ratios (0.10-0.35; avg. 0.21), low DOP values (0.11-0.40; avg. 0.28), and S/C values are clustering on the normal marine value (S/C = 0.36). The late Hirnantian and early Rhuddanian deposits, similar to those of the Middle Ashgill deposits, are characterized by high FeHR/FeT ratios (0.32-0.49; avg. 0.41), high DOP values (0.46-0.68; avg. 0.53) and fairly constant sulfur contents. These data suggest the occurrences of marine anoxia on the Yangtze Sea shelf during intervals of the Mid Ashgill, Late Hirnantian and Early Rhuddanian, and ventilated and oxygenated marine conditions during the mid-early Hirnantian time. The mid-early Hirnantian ventilated event was concomitant with the global glacial period, likely resulted from the glacio-eustatic sea-level fall and subsequent circulation of cold, dense oxygenated waters upon the shelf seabed. Accordingly, the abrupt change from oxygenated to anoxic marine waters from the late Hirnantian and the early Rhuddanian were resulted from the post-glacial rise of eustatic sea level. Combined with the data from Sanjiaguan section near the subemergent highland, salinity stratification of water columns are strongly evidenced by very low S/C ratios (0.00-0.08, avg. 0.02), low FeHR/FeT ratios (0.10-0.37, avg. 0.27), low DOP values (0.01-0.27, avg. 0.10), and TOC contents (0.72%-4.27%, avg. 2.55%). Under this circumstance, the anoxic water columns could have formed beneath the halocline, above which desalinized waters formed. In the Wangjiawan section, TOC contents are generally high (0.94-9.32%, avg. 4.44%), but low (0.35%-2.12%, avg. 1.29%) in the mid-early Hirnantian that is coincident with the oceanic oxic stage, together with relation of the organic contents to the stratal thickness, suggesting that the accumulation of the organic matter was mainly controlled by the oxygen levels of the water columns; on the other hand, productivity and depositional rate may also have played a role in the organic accumulation and preservation.
- Published
- 2010
11. Optical Design of Rigid Endoscope with 30° Viewing Angle
- Author
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Zhang Shuqing, Zhi Xiyang, Wang Qingchen, and Huang Yuanxin
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Optics ,Materials science ,business.industry ,Rigid endoscope ,business ,Viewing angle ,Atomic and Molecular Physics, and Optics ,Electronic, Optical and Magnetic Materials - Published
- 2018
12. Denim Defect Detection Based on Optimal Gabor Filter
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景军锋 Jing Junfeng, 王清晨 Wang Qingchen, 王晓华 Wang Xiaohua, 张蕾 Zhang Lei, and 李鹏飞 Li Pengfei
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Gabor filter ,business.industry ,Computer science ,020208 electrical & electronic engineering ,0202 electrical engineering, electronic engineering, information engineering ,Pattern recognition ,02 engineering and technology ,Artificial intelligence ,Electrical and Electronic Engineering ,Denim ,business ,Atomic and Molecular Physics, and Optics - Published
- 2018
13. Exhumation of the Dabie UHP Terrane, China
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Wang Qingchen, Lin Wei, Guo Jinghui, and Shi YongHong
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Blueschist ,Craton ,geography ,geography.geographical_feature_category ,Subduction ,Lithosphere ,North china ,Geology ,Petrology ,Foreland basin ,Seismology ,Terrane - Abstract
Exhumation of deeply buried ultrahigh-pressure (UHP) terranes remains a puzzle in understanding lithospheric dynamic process. New evidence that constrains the exhumation process of the Dabie UHP terrane includes the following. (1) Structural data record the architecture of the Dabie UHP terrane. Three slices are recognized—i.e., from top to bottom, the Susong blueschist slice, the Huangzhen-Huangweihe (HH) HP slice, and the Jinheqiao-Shuanghe-Bixiling (JSB) UHP slice. These slices have been stacked and domed. (2) Geophysical data depict two offsets in the Moho. Offset-I separates the Dabie UHP terrane from the North China craton, and has served as a subduction channel, as well as an exhumation channel. Offset-II, separating the Dabie UHP terrane from the foreland belt, developed due to geodynamic regime reorganization. (3) Geochronological data reveal that the HP slice was exhumed earlier that the UHP slice. A northward-younging exhumation polarity is implied, with younger exhumation age closer to the exh...
- Published
- 2008
14. Propagation Characteristics of Dielectric-Loaded Graphene Plasma Waveguides
- Author
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宋 梁 Song Liang and 王清晨 Wang Qingchen
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Materials science ,business.industry ,Graphene ,02 engineering and technology ,Plasma ,Dielectric ,021001 nanoscience & nanotechnology ,01 natural sciences ,Atomic and Molecular Physics, and Optics ,law.invention ,010309 optics ,law ,0103 physical sciences ,Optoelectronics ,Electrical and Electronic Engineering ,0210 nano-technology ,business ,Graphene nanoribbons - Published
- 2017
15. A multidiscipline method of geological survey, seismic profile and gravity measurement applied to fold-and-thrust belt: a case study along the Hutubi River in the northern piedmont of Tianshan
- Author
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Chen, Ke, Gumiaux, Charles, Augier, Romain, Chen, Yan, Mei, Yan-Hui, Lin, Wei, Wang, Qingchen, Oil & Gas Survey, China Geological Survey, Institut des Sciences de la Terre d'Orléans - UMR7327 (ISTO), Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Bureau de Recherches Géologiques et Minières (BRGM) (BRGM), State Key Laboratory of Lithospheric Evolution (SKL), Institute of Geology and Geophysics [Beijing] (IGG), and Chinese Academy of Sciences [Beijing] (CAS)-Chinese Academy of Sciences [Beijing] (CAS)
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[SDU.STU.TE]Sciences of the Universe [physics]/Earth Sciences/Tectonics ,Tianshan ,Structural observation ,Seismic profile ,Multidisciplinary ,Fold-and-thrust belt ,[SDU]Sciences of the Universe [physics] ,[SDU.STU]Sciences of the Universe [physics]/Earth Sciences ,Gravity measurements - Abstract
International audience; Fold-and-thrust belts are hot topics in the research of orogens. However, the single geological or geophysical discipline often provides multisolutions on the geometry of a fold-and-thrust belt. We introduce here a multidisciplinary method combining geological and geophysical methods, take the Hutubi River section as a case to study the geometry of the fold-and-thrust belt in the northern piedmont of Tianshan. Firstly, we have carefully taken geological survey and got structural data on the surface. Secondly, petroleum seismic profile was re-interpreted based on the surface data and drilled wells. However, the seismic profile is absent in the contact zone between the mountain and the Junggar basin. We therefore carried out gravity measurements and forward modeling along this profile with the densities of the basement and sediments. The result shows that the northern flank fault of Tianshan doesn't exist along the Hutubi River profile, and the basin sediments could be continually followed from the basin to the mountain interior. This indicates that the tectonic structures in the contact zones between the mountain and the basin are variable, as the western section in the Jingou River section shows that the Tianshan basement thrusts northward on the basin sediments. Based on the balance-section technology, the restored section shows 4. 8 km of shortening. Comparing with previous results, this indicates the heterogeneous deformation along the northern piedmont of Tianshan. It also implies that this multidisciplinary method could be widely used in the fold-and-thrust belt.
- Published
- 2014
16. New Data Regarding Hotly Debated Topics Concerning UHP Metamorphism of the Dabie-Sulu Belt, East-Central China
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Wang Qingchen, Zhai Mingguo, and Cong Bolin
- Subjects
Recrystallization (geology) ,Subduction ,Mantle wedge ,Oceanic crust ,Lithosphere ,Metamorphic rock ,Geochemistry ,Metamorphism ,Geology ,Eclogite - Abstract
Critical but controversial problems in the study of UHP metamorphic rocks from the Dabie-Sulu region include: (1) the possible existence of ophiolitic melange; (2) the “in situ” versus “foreign” origin of UHP eclogites and their enclosing gneisses; (3) the possible presence and role of fluids during ultrahigh-pressure (UHP) recrystallization; (4) the timing of collision between the Yangtze and Sino-Korean continental blocks; (5) the polarity of syncollisional subduction; and (6) a single-versus multistage exhumation scenario for the UHP rocks. These questions are discussed in light of new geological, geochemical, and isotopic constraints. Our conclusions for the Dabie-Sulu belt are as follows: (1) Mafic-ultramafic blocks are of two distinct origins: one group samples lithosphere of the suprasubductionzone mantle wedge, whereas the second group represents postcollisional magmatic intrusions. Neither lithologic group represents true oceanic crust. (2) Quartzofeldspathic gneisses enveloping the eclogites are...
- Published
- 1999
17. Structural coupling of the Dabie Orogen with Hefei Basin
- Author
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Ma Li, Wang Qingchen, and Cong Bolin
- Subjects
Structural coupling ,Multidisciplinary ,Inversion (geology) ,Geochemistry ,Orogeny ,Mesozoic ,Structural basin ,Geomorphology ,Mantle (geology) ,Geology - Abstract
Geological, geophysical and geochemical data show that both of the Dabie Orogen and Hefei Basin formed during a Mesozoic orogeny. A three-stage development of the Hefei Basin includes down-warping, half grabben, and positive inversion. Both the uplift in orogen and the depression in basin resulted from the “de-rooting” of orogen and up-welling of the mantle.
- Published
- 1997
18. Late Mesozoic compressional to extensional tectonics in the Yiwulüshan massif, NE China and its bearing on the evolution of the Yinshan-Yanshan orogenic belt: Part I: Structural analyses and geochronological constraints
- Author
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Lin, Wei, Faure, Michel, Chen, Yan, Ji, Wenbin, Wang, Fei, Wu, Lin, Charles, Nicolas, Wang, Jun, Wang, Qingchen, State Key Laboratory of Lithospheric Evolution (SKL), Institute of Geology and Geophysics [Beijing] (IGG), Chinese Academy of Sciences [Beijing] (CAS)-Chinese Academy of Sciences [Beijing] (CAS), Institut des Sciences de la Terre d'Orléans - UMR7327 (ISTO), Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Bureau de Recherches Géologiques et Minières (BRGM) (BRGM), and NSFC 90714007, 40872142
- Subjects
Yinshan-Yanshan fold and thrust belt ,Yiwulüshan massif ,[SDU.STU.TE]Sciences of the Universe [physics]/Earth Sciences/Tectonics ,[SDE.MCG]Environmental Sciences/Global Changes ,Structural analysis ,Polyphase deformations ,North China Craton - Abstract
International audience; With a cratonic nucleus, the North China Craton (NCC) experienced a complex tectonic evolution with multiphase compressional and extensional events during Mesozoic times. Along the northern part of the NCC, the Yinshan-Yanshan fold and thrust belt was a typical intraplate orogen. Jurassic and Cretaceous continental sedimentation, magmatism, widespread intraplate characterize the Yinshan-Yanshan orogenic belt. The geodynamic significance of these tectonic events is still in dispute. In the western part of the Liaoning province, the Yiwulüshan massif crops out at the eastern end of the Yinshan-Yanshan orogenic belt. The Yiwulüshan massif presents an elliptical domal shape with a NE-SW striking long axis. The structural evolution of this massif brings new insights for the understanding of the Mesozoic plutonic-tectonic history of the NCC. A multidisciplinary study involving structural geology, geochronology, Anisotropy of Magnetic Susceptibility (AMS) and gravity modeling have been carried out. The presentation of the new results splits into two parts. Part I (this paper) deals with field and laboratory structural observations, and presents the main geochronological results. The AMS, gravity modeling data will be provided in a companion paper (Part II). The early compressional deformation (D1) corresponds to a Late Jurassic to Early Cretaceous southward thrusting. The subsequent deformation is related to the Early Cretaceous exhumation of the Yiwulüshan massif. A detailed structural analysis allows us to distinguish several deformation events (D2, D3, and D4). The Cretaceous extensional structures, such as syntectonic plutons bounded by ductile normal faults, metamorphic core complexes, and half-graben basins are recognized in many places in East Asia. These new data from the Yiwulüshan massif constitute a link between Transbaikalia, Mongolia, North China and South China, indicating that NW-SE extensional Mesozoic tectonics occurred throughout the entire region.
- Published
- 2013
19. Late Mesozoic compressional to extensional tectonics in the Yiwulüshan massif, NE China and their bearing on the Yinshan-Yanshan orogenic belt: Part II: Anisotropy of magnetic susceptibility and gravity modeling
- Author
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Lin, Wei, Charles, Nicolas, Chen, Yan, Chen, Ken, Faure, Michel, Wu, Lin, Wang, Fei, Li, Qiuli, Wang, Jun, Wang, Qingchen, State Key Laboratory of Lithospheric Evolution (SKL), Institute of Geology and Geophysics [Beijing] (IGG), Chinese Academy of Sciences [Beijing] (CAS)-Chinese Academy of Sciences [Beijing] (CAS), Institut des Sciences de la Terre d'Orléans - UMR7327 (ISTO), Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Bureau de Recherches Géologiques et Minières (BRGM) (BRGM), and NSFC 90714007, 40872142
- Subjects
Yinshan-Yanshan fold and thrust belt ,Yiwulüshan massif ,[SDU.STU.TE]Sciences of the Universe [physics]/Earth Sciences/Tectonics ,[SDE.MCG]Environmental Sciences/Global Changes ,Anisotropy of magnetic susceptibility ,Late Mesozoic tectonic evolution ,Gravity modeling ,North China Craton - Abstract
International audience; Granitoids play an important role in deciphering both crustal growth and tectonic evolution of Earth. In the eastern end of the Yinshan-Yanshan belt of North China Craton, the Yiwulüshan massif is a typical region that presents the tectonic evolution features of this belt. Our field work on the host rocks has demonstrated two phases of opposite tectonics: compressional and extensional, however, the deformation is almost invisible in the intrusive rocks. To improve the understanding of the tectonic evolution of the Yiwulüshan massif and the Late Mesozoic tectonics of East Asia, a multidisciplinary study has been carried out. In this study, anisotropy of magnetic susceptibility (AMS) and gravity modeling have been applied on these Jurassic plutons (Lüshan, Jishilazi and Guanyindong), which intrude into the Yiwulüshan massif. According to laboratory measurements and microscopic observations on thin sections, the AMS of the Yiwulüshan massif is characterized by secondary fabrics, indicating that the intensive post solidus deformation has reset the (primary) magmatic magnetic fabrics. A relatively gentle NW dipping magnetic foliation has been identified with two distinct groups of magnetic lineations of N34°E and N335°E orientations, namely LM1 and LM2, relatively. Gravity modeling reveals a southward thinning of the massif with a possible feeding zone rooted in the northern part of the massif. Integrating all results from structural observation, geochronological investigation, AMS measurement and gravity modeling, two tectonic phases have been identified in the Yiwulüshan massif, posterior to the Jurassic (180-160 Ma) magmatism in the Yinshan-Yanshan area. The early one concerns a Late Jurassic-Early Cretaceous (~ 141 Ma) compressional event with a top-to-the-south to southwest sense of shear. The second one shows an Early Cretaceous (~ 126 Ma) NW-SE ductile extensional shearing. At that time, sedimentary basins widened and Jurassic plutons started to be deformed under post solidus conditions. In fact, the NW-SE trend of the maximum stretching direction is a general feature of East Asian continent during Late Mesozoic.
- Published
- 2013
20. Top boundary of the Dabie UHPM rocks, central China
- Author
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Cong Bolin, Liu Xiaohan, Wang Qingchen, and Shigenori Maruyama
- Subjects
Felsic ,Metamorphic rock ,Geochemistry ,Feldspar ,Shear (geology) ,visual_art ,Earth and Planetary Sciences (miscellaneous) ,visual_art.visual_art_medium ,General Earth and Planetary Sciences ,Clockwise ,Shear zone ,Quartz ,Geology ,General Environmental Science ,Gneiss - Abstract
The top boundary of the ultra-high pressure metamorphic (UHPM) rocks in the Dabie Mountains, central China, has been mapped. The results show that the top boundary of the UHPM rocks is occupied by flat-lying felsic gneiss, on which tonalitic gneiss rests. Petrological and mineralogical evidence indicates a wide P-T gap across the boundary with an estimated peak metamorphic P-T value of the UHPM rocks being >30 kbar and 800 ± 50°C, and that of the tonalitic gneiss around 11 kbar and 800°C. Their P-T-t paths are different. The former has a clockwise path and the latter is counterclockwise. This implies that the UHPM rocks at the bottom and the tonalitic gneiss on top have been structurally juxtaposed together. The top boundary, i.e. the contact between the UHPM rocks and tonalitic gneiss, shows characteristics of a ductile shear zone. Microscopically, feldspar and quartz in the shear zone are characterized by ductile deformation. In larger scale, the top boundary is undulating. Shear sense in the top boundary is a two-way direction. Only the latest shear sense measured with c -axes of quartz show a consistent direction of top-to-the-north. The study provides some constraints to the exhumation process of the Dabie UHPM rocks.
- Published
- 1995
21. Petrogenesis of ultrahigh-pressure rocks and their country rocks at Shuanghe in Dabieshan, Central China
- Author
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Zhao Zhongyan Zhao Zhongyan, Wang Qingchen, Zhai Mingguo, Brian F. Windley, R. N. Wilson, Dennis A. Carswell, and Cong Bolin
- Subjects
Geochemistry and Petrology ,Geochemistry ,Central china ,Geology ,Petrogenesis - Published
- 1995
22. Petrological-tectonic units in the coesite-bearing metamorphic terrain of the Dabie Mountains, central China and their geotectonic implications
- Author
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Zhai Mingguo, Wang Qingchen, Zhao Zhongyan Zhao Zhongyan, Cong Bolin, Wang Gang, and Jiang Laili
- Subjects
Metamorphic rock ,Geochemistry ,Metamorphism ,Granulite ,Basement (geology) ,Earth and Planetary Sciences (miscellaneous) ,General Earth and Planetary Sciences ,Shear zone ,Eclogite ,Geomorphology ,Geology ,Metamorphic facies ,General Environmental Science ,Gneiss - Abstract
Four main faults outline the metamorphic terrain in the Dabie Mountains, central China. The difference of metamorphic grade in the northern, central and southern parts is well-established. This study suggests that these metamorphic rocks belong to three individual geological-tectonic units, which are the northern Andean-type magmatic arc, the central UHPM rock-bearing melange zone and the mobilized sedimentary cover and basement of Yangtze southern continental margin. An old ductile sheared zone through Wuhe and the south of Yuexi-Shuihou divides the Dabie metamorphic complex into northern and central units. The northern unit is predominantly occupied by tonalitic-trondhjemitic grey gneisses and amphibolites facies metasediments. Several approximately E-W-trending ductile-sheared mylonitic belts cut through the grey gneisses, and are especially developed in the northern and southern margins of the unit (high-strain zones). There is a series of lenses of basic granulites, serpentinites and Grt-pyroxenites in the high-strain zones. They do not have the petrological and geochemical characteristics of ophiolitic rocks. However, they may represent the root of an arc combined with grey gneisses. Our study also demonstrates that all rocks from the northern block did not undergo eclogite facies metamorphism. Mesozoic post-collisional granites occur extensively in the Dabie terrain, especially in the northern unit. Coesite and diamond-bearing eclogites in the central unit indicate a regional ultra-high-pressure metamorphism of pressures of > 30 kbar and temperature of 600–800°C. Except for eclogites, various ultra-high-pressure metamorphic (UHPM) rocks include ultramafic rocks, marbles and other metamorphosed sedimentary rocks. They, as large-scale blocks, are mixed with lower P-T encompassing host rock orthogneisses. The central block is a UHPM rock-bearing melange zone. The south block is a metasedimentary sequence of continental margin of the Yangtze plate. The boundary between the central and southern blocks is located in the north from Huangzhen, extending eastwards through the dam of Huangliangting reservoir. In addition, the Foziling Group, north of the Dabieshan terrain was possibly deposited in an extensional basin on an extensional shear zone, comparable to the basin in the Variscan of France and the Caledonides of S. Norway (Dewey, Ryan and Anderson, Geological Society Special Publication No. 76, pp. 325–343, 1993). The authors hope that this information will provide more valid evidence of regional tectonic evolution.
- Published
- 1995
23. Phanerozoic tectonothermal events of the Xuefengshan Belt, central South China: Implications from Usingle bondPb age and Lusingle bondHf determinations of granites
- Author
-
Chu, Yang, Lin, Wei, Faure, Michel, Wang, Qingchen, Ji, Wenbin, State Key Laboratory of Lithopheric Evolution, Institute of Geology and Geophysics, Institut des Sciences de la Terre d'Orléans - UMR7327 (ISTO), Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Bureau de Recherches Géologiques et Minières (BRGM) (BRGM), Graduate university of Chinese Academy, Graduate University of Chinese Academy, State Key Laboratory of Lithospheric Evolution (SKL), Institute of Geology and Geophysics [Beijing] (IGG), Chinese Academy of Sciences [Beijing] (CAS)-Chinese Academy of Sciences [Beijing] (CAS), and Innovative Project of the Chinese Academy of Sciences (Grant No. KZCX1-YW-15-1) and Major State Basic Research Development Program of China (2009CB825008)
- Subjects
SIMS Usingle bondPb zircon dating ,[SDU.STU.TE]Sciences of the Universe [physics]/Earth Sciences/Tectonics ,[SDE.MCG]Environmental Sciences/Global Changes ,Phanerozoic tectonothermal events ,Xuefengshan Belt ,Lusingle bondHf isotopes ,South China - Abstract
International audience; The Xuefengshan Belt, characterized by large-scale fold and thrust structures and widespread granites, is a key area to decipher the tectonic evolution of the South China block. In this belt, two magmatic episodes are recorded by Early Paleozoic and Early Mesozoic granites. In this paper, we carried out precise SIMS zircon Usingle bondPb dating and in situ Lusingle bondHf isotopes measurements on these granitic plutons. Our study indicates that the Early Paleozoic and the Early Mesozoic granites are late-orogenic products of the Early Paleozoic orogen and the Middle Triassic Xuefengshan orogen, respectively. In the Xuefengshan Belt, the Early Paleozoic event is poorly registered, since this area corresponds to the outer zone of the early Paleozoic orogen. The Silurian-Early Devonian granites are late-orogenic plutons emplaced after the main tectonic and metamorphic stage in the Wuyi-Baiyun-Yunkai belt, coeval with a widespread, subsequent extensional event in eastern and southern South China. On the other hand, Triassic granites are formed in an intracontinental environment with weakly to strongly peraluminous signatures. Zircon Usingle bondPb ages presented here, associated with a summary of newly acquired data in the same region, suggest that the emplacement of anatectic granites occurred around 225-215 Ma, not in a rather wide range of ca. 245-200 Ma. In situ zircon εHf(t) values indicate a crust-derived source without a mantle-derived input for the two generations of granites. Combining our data with recent studies, we infer that the central area of the South China block has experienced two tectonothermal events: the Early Paleozoic magmatism developed as a result of the collapse of the Early Paleozoic orogen, while these Early Mesozoic granites can be the late-orogenic products of the intracontinental Xuefengshan orogen, most likely manifesting the far field effect by the
- Published
- 2012
24. The Northern Dabieshan Terrain: A Possible Andean-Type Arc
- Author
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Wang Qingchen, Zhang Qi, Cong Bolin, and Zhai Mingguo
- Subjects
Arc (geometry) ,Back-arc basin ,Metamorphic rock ,Geochemistry ,Geology ,Terrain ,Petrology ,Gneiss - Abstract
The northern Dabieshan metamorphic terrain (NDT) is an analogue of an Andean-type magmatic arc. The predominant rock type is a trondhjemitic-tonalitic-granodioritic (TTG) gneiss with bodies of meta...
- Published
- 1994
25. Ultra-high pressure metamorphic rocks in the Dabie-Su-Lu region, China: Their formation and exhumation
- Author
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Cong Bolin, Wang Qingchen, Zhang Ruyuan, Zhao Zhongyan Zhao Zhongyan, Zhai Mingguo, and Ye Kai
- Subjects
Blueschist ,Metamorphic rock ,Geochemistry ,Metamorphism ,Geology ,Eclogite ,Petrology ,Granulite ,Protolith ,Metamorphic facies ,Gneiss - Abstract
Based on petrological, structural, geological and geochronological research, the authors summarize the progress of ultra-high pressure (UHP) metamorphic rock study since 1989 by Chinese geoscientists and foreign geoscientists in the Dabie-Su-Lu region. The authors introduce and discuss a two-stage exhumation process for the UHP metamorphic rocks that have various lithologies; eclogite, ultramafics, jadeitic quartzite, gneiss, schist and marble. The metamorphic history of UHP metamorphic rocks is divided into three stages, that is, the pre-eclogite stage, coesite eclogite stage, and retrograde stage. Prior to UHP metamorphism, the ultramafics had a high temperature environment assemblage of mantle and others had blueschist facies assemblages. The granulite facies assemblages, which have recorded a temperature increase event with decompression, have developed locally in the Weihai basaltic rocks. Isotopic ages show a long range from > 700 Ma to 200 Ma. The diversity in protoliths of UHP metamorphic rocks may be related to the variation of isotopic ages older than 400 Ma. The Sm-Nd dating of ~ 220 Ma could reflect the initial exhumation stage after the peak UHP metamorphism in relation to the collision between the Sino-Korean and Yangtze blocks and subsequent events. Petrological and structural evidence imply a two-stage exhumation process. During the initial exhumation, the UHP metamorphic rocks were sheared and squeezed up in a high P/T regime. In the second exhumation stage the UHP metamorphic rocks were uplifted and eventually exposed with middle crustal rocks.
- Published
- 1994
26. The Mesozoic palaeorelief of the northern Tian Shan (China)
- Author
-
Chen, Ke, Gumiaux, Charles, Augier, Romain, Chen, Yan, Wang, Qingchen, Lin, Wei, Wang, Shengli, Institut des Sciences de la Terre d'Orléans (ISTO), Université de Tours-Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), State Key Laboratory of Lithospheric Evolution (SKL), Institute of Geology and Geophysics [Beijing] (IGG), Chinese Academy of Sciences [Beijing] (CAS)-Chinese Academy of Sciences [Beijing] (CAS), Department of Earth Sciences [Nanjing], Nanjing University (NJU), Chinese National 973 Program (2009CBS25008) and Chinese National S&T Major Project 2011ZX05008, and Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Université de Tours (UT)-Centre National de la Recherche Scientifique (CNRS)
- Subjects
[SDU.STU.TE]Sciences of the Universe [physics]/Earth Sciences/Tectonics ,[SDE.MCG]Environmental Sciences/Global Changes - Abstract
International audience; The Tian Shan range offers a natural laboratory to study orogenic processes. Most of the previous studies focused on either the Palaeozoic evolution of the range or its Cenozoic intracontinental evolution linked with the India-Asia collision. In this study, it is shown that detailed field investigations on the relationship between sedimentary cover and basement constrain the Mesozoic evolution of the northern Tian Shan. Sedimentological observations argue for a limited transport distance for Lower and Uppermost Jurassic deposits. Geological sections presented in this paper show that, in preserved locations, Triassic to Jurassic sedimentary series present a continuous onlap type sedimentary unconformity on the top of the basement. At different scales, observations clearly evidence the existence of major palaeorelief during the Mesozoic. According to the present study, the topography of the current Tian Shan range and the associated movements along its northern front structures cannot be considered as the consequence of Cenozoic reactivation alone.
- Published
- 2011
27. Coesite-bearing granulite retrograded from eclogite in Weihai, eastern China
- Author
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Zhai Mingguo, Takao Hirajima, Nobuki Hiramatsu, Cong Bolin, Li Jiaju Li Jiaju, Zhao Zhongyan Zhao Zhongyan, Wang Qingchen, Masaki Enami, and Akira Ishiwatari
- Subjects
Albite ,Geochemistry and Petrology ,Coesite ,engineering ,Geochemistry ,Plagioclase ,Epidote ,engineering.material ,Eclogite ,Omphacite ,Granulite ,Geology ,Hornblende - Abstract
Coesite in a granulite host-rock is reported from Weihai City, northeastern Shandong Province, China. Coesite occurs as inclusions in garnet, which is separated from the fine-grained matrix of quartz + clinopyroxene + homblende by a zoned corona of plagioclase + clinopyroxene + orthopyroxene + hornblende. Petrological evidence shows that the coesite-bearing granulite is retrograded from eclogite. Three stages in the metamorphic history of the granulite have been recognized. (i) Coesite-eclogite stage: The assemblage reconstructed from the inclusions in garnet is Mg-rich garnet + omphacite + coesite + rutile. (ii) During the granulite stage, these minerals reacted to form quartz + clinopyroxene + hornblende (in the matrix), clinopyroxene + albite (omphacite pseudomorphs) and plagioclase + clinopyroxene + orthopyroxene + hornblende (as corona around garnet). (iii) Amphibolite stage: Earlier minerals were replaced by biotite, epidote and hornblende. The P-T conditions estimated with various geothermobarometers show a T-increasing and P-decreasing path from the eclogite stage (T ∼ 720°C, P > 28 kbar) to the granulite stage (T ∼ 850°C, P ∼ 10 kbar). Thus the exhumation of the ultra-high-pressure rocks in Weihai proceeded under increasing temperature, and may not have been as fast as it was thought before
- Published
- 1993
28. Mesozoic and Cenozoic tectonic history of the central Chinese Tian Shan: Reactivated tectonic structures and active deformation
- Author
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Jolivet, M., Dominguez, Stephane, Charreau, Julien, Chen, Yan, Li, Yongan, Wang, Qingchen, Terre, Temps, Traçage, Géosciences Rennes (GR), Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre Armoricain de Recherches en Environnement-Centre National de la Recherche Scientifique (CNRS)-Université de Rennes 1 (UR1), Université de Rennes (UNIV-RENNES)-Université de Rennes (UNIV-RENNES)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre Armoricain de Recherches en Environnement-Centre National de la Recherche Scientifique (CNRS), Géosciences Montpellier, Université des Antilles et de la Guyane (UAG)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Centre de Recherches Pétrographiques et Géochimiques (CRPG), Institut national des sciences de l'Univers (INSU - CNRS)-Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS), Institut des Sciences de la Terre d'Orléans (ISTO), Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Université de Tours (UT)-Centre National de la Recherche Scientifique (CNRS), Xinjiang Institute of Ecology and Geography [Urumqi] (XIEG), Chinese Academy of Sciences [Beijing] (CAS), Institute of Geology and Geophysics [Beijing] (IGG), Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre Armoricain de Recherches en Environnement-Centre National de la Recherche Scientifique (CNRS)-Université de Rennes (UR)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre Armoricain de Recherches en Environnement-Centre National de la Recherche Scientifique (CNRS), and Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Université de Tours-Centre National de la Recherche Scientifique (CNRS)
- Subjects
tectonic inheritance ,[SDU.STU.TE]Sciences of the Universe [physics]/Earth Sciences/Tectonics ,India-Asia collision ,[SDE.MCG]Environmental Sciences/Global Changes ,Tian Shan ,low-temperature thermochronology ,relief ,fission tracks - Abstract
International audience; The present-day topography of the Tian Shan range is considered to result from crustal shortening related to the ongoing India-Asia collision that started in the early Tertiary. In this study we report evidence for several episodes of localized tectonic activity which occurred prior to that major orogenic event. Apatite fission track analysis and (U-Th)/He dating on apatite and zircon indicate that inherited Paleozoic structures were reactivated in the late Paleozoic-early Mesozoic during a Cimmerian orogenic episode and also in the Late Cretaceous-Paleogene (around 65-60 Ma). These reactivations could have resulted from the accretion of the Kohistan-Dras arc or lithospheric extension in the Siberia-Mongolia zone. Activity resumed in the late Mesozoic prior to the major Tertiary orogenic phase. Finally, the ongoing deformation, which again reactivates inherited tectonic structures, tends to propagate inside the endoreic basins that were preserved in the range, leading to their progressive closure. This study demonstrates the importance of inherited structures in localizing the first increments of the deformation before it propagates into yet undeformed areas.
- Published
- 2010
29. The immature thrust belt of the northern front of the Tianshan
- Author
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Chen, Ke, Gumiaux, Charles, Augier, Romain, Chen, Yan, Wang, Qingchen, Institut des Sciences de la Terre d'Orléans (ISTO), Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Université de Tours-Centre National de la Recherche Scientifique (CNRS), State Key Laboratory of Lithospheric Evolution (SKL), Institute of Geology and Geophysics [Beijing] (IGG), Chinese Academy of Sciences [Beijing] (CAS)-Chinese Academy of Sciences [Beijing] (CAS), POTHIER, Nathalie, and Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Université de Tours (UT)-Centre National de la Recherche Scientifique (CNRS)
- Subjects
[SDU.STU.TE]Sciences of the Universe [physics]/Earth Sciences/Tectonics ,[SDE.MCG] Environmental Sciences/Global Changes ,[SDE.MCG]Environmental Sciences/Global Changes ,[SDU.STU.TE] Sciences of the Universe [physics]/Earth Sciences/Tectonics - Abstract
International audience; The modern Tianshan (central Asia), which extends east-west on about 2500 km long with an average of more than 2000 m in altitude, is considered as a direct consequence of the reactivation of a Paleozoic belt due to the India - Asia collision. At first order, the finite structure of this range obviously displays a significant uprising of Paleozoic "basement" rocks - as a crustal-scale 'pop-up' - surrounded by two Cenozoic foreland basins. In order to characterize the coupling history of this Cenozoic orogeny with its northern foreland basin (Junggar basin), a detailed structural field work has been carried out on the northern piedmont of Tianshan. From Wusu to Urumqi, on about 250 km long, the thrusting of the Paleozoic basement on the Mesozoic or Cenozoic sedimentary series of the basin is remarkably exposed along several river valleys. In contrast, in other sections, the Triassic to Jurassic sedimentary series can be followed from the basin to the range where they unconformably overlie on the Carboniferous basement. These series are only gently folded along the "range front". These features imply that, at regional-scale, the Cenozoic reactivation of the Tianshan has not produced important deformation along its contact with the juxtaposed Junggar basin. The shortening ascribed to the Cenozoic intra-continental collision would either be localized in the range, mostly accommodated by reactivated Paleozoic structures or faults in the basement units, or in the distal parts of the Junggar basin, by folds and faults within the Cenozoic sedimentary series. Alternative hypothesis would be that the Tianshan uplift and the movements associated with along its northern front structures, which are traditionally assigned to its Cenozoic reactivation, might be reduced. Such characteristic significantly differs from other well-known orogenic ranges, such as the Canadian Rocky Mountains, the Appalachians, the Pyrenees which display highly folded foreland basins and thrust belts with rather well developed range front structures. This suggests that the Tianshan intra-continental range is rather "young" and still at a primary stage of its orogenic evolution. In other words, its front may be considered as an immature thrust belt. If considering the available tomographic data across the Tianshan, its actual uplift may probably be produced by an asymmetric intracontinental deformation mechanism, i.e. a deeper subduction of the Tarim plate below the Tianshan (to the south), with respect to the one of Junggar plate to the north of the range. Consequently, the Tianshan range offers an excellent natural laboratory to study the processes of the on-going orogeny-foreland basin coupling, ancient structures reactivation as well as initiation and development of range front structures.
- Published
- 2010
30. Field evidences for a Mesozoic palaeo-relief through the northern Tianshan
- Author
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Gumiaux, Charles, Chen, Ke, Augier, Romain, Chen, Yan, Wang, Qingchen, Institut des Sciences de la Terre d'Orléans (ISTO), Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Université de Tours (UT)-Centre National de la Recherche Scientifique (CNRS), State Key Laboratory of Lithospheric Evolution (SKL), Institute of Geology and Geophysics [Beijing] (IGG), Chinese Academy of Sciences [Beijing] (CAS)-Chinese Academy of Sciences [Beijing] (CAS), POTHIER, Nathalie, and Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Université de Tours-Centre National de la Recherche Scientifique (CNRS)
- Subjects
[SDU.STU.TE]Sciences of the Universe [physics]/Earth Sciences/Tectonics ,[SDE.MCG] Environmental Sciences/Global Changes ,[SDE.MCG]Environmental Sciences/Global Changes ,[SDU.STU.TE] Sciences of the Universe [physics]/Earth Sciences/Tectonics - Abstract
International audience; The modern Tianshan mountain belt, located in Central Asia, offers a natural laboratory to study orogenic processes linked with convergent geodynamical settings. Most of the previous studies either focused on the Paleozoic evolution of the range - subductions, arc accretions and continental collision - or on its Cenozoic intra-continental evolution linked with the India-Asia collision. At first order, the finite structure of this range obviously displays a remarkable uprising of Paleozoic "basement" rocks - as a crustal-scale 'pop-up' - surrounded by two Cenozoic foreland basins. The present-day topography of the Tianshan is traditionally related to the latest intra-continental reactivation of the range. In contrast, the present field study of the northern Tianshan brings new and clear evidences for the existence of a significant relief, in this area, during Mesozoic times. The investigation zone is about 250 km long, from Wusu to Urumqi, along the northern flank of the Tianshan where the rivers deeply incised the topography. In such valleys, lithologies and structural relationships between Paleozoic basement rocks, Mesozoic and Cenozoic sedimentary series are particularly well exposed along several sections. Jurassic series are mostly characterized by coal-bearing, coarse-grained continental deposits. Within intra-mountain basins, sedimentary breccias, with clasts of Carboniferous basement rocks, have been locally found at the base of the series. This argues for the presence of a rather proximal palaeo-relief of basement rocks along the range front and the occurrence of proximal intra-mountain basins, during the Jurassic. Moreover, while a major thrust is mostly evoked between Jurassic deposits and the Paleozoic units, some of the studied sections show that the Triassic to Jurassic sedimentary series can be followed from the basin to the range. In these cases, the unconformity of the Mesozoic series on top of the Carboniferous basement has been locally clearly identified quite high in the mountain range or even, surprisingly, directly along the northern Tianshan "front" itself. Combining available information from geological maps, field investigations and numerous drilling wells, regional-scale cross-sections have been built. Some of them show "onlap" type deposit of the Triassic to Jurassic clastic sediments on top of the Paleozoic basement that was thus significantly sloping down to the North at that time. Our study clearly evidences, at different scales, the existence of a major palaeo-relief along the northern Tianshan range during Mesozoic, and particularly during Jurassic times. Such results are compatible with previous fission tracks and sedimentology studies. From this, the Tianshan's uplift and the movements associated with along its northern front structures, which are traditionally assigned to its Cenozoic reactivation, must be reduced. These new results question on the mode and timing of reactivation of structures and on the link between topography and intra-continental collisional settings.
- Published
- 2010
31. The distribution characteristics of turbulence on leeside of windbreaks
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Wang Ke, Wang Qingchen, Wang Zhengquan, and Zhang Yandong
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Horizontal and vertical ,Turbulence ,Forestry ,Mechanics ,Reynolds stress ,Windbreak ,Wind speed ,Nonlinear Sciences::Chaotic Dynamics ,Physics::Fluid Dynamics ,Distribution (mathematics) ,Distributive property ,Physics::Space Physics ,Intensity (heat transfer) ,Geology - Abstract
The distributive characteristics of turbulence, turbulent velocity, turbulent intensity and Reynolds stress, in horizontal and vertical direction on leeward side of windbreak were discussed in this paper. The results show that all the three kinds of parameters of turbulence have the similar distributive patterns in lee, their peaks were around 10H for horizontal andZ/ H = 1 for vertical. The windbreak is important barrier to affect the structure and distribution of wind speed and turbulence. Porosities of windbreaks could alter the patterns of turbulence, therefore, affect the abilities and functions of windbreaks.
- Published
- 1992
32. Neogene uplift of the Tian Shan Mountains observed in the magnetic record of the Jingou River section (northwest China)
- Author
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Charreau, Julien, Chen, Yan, Gilder, Stuart, Barrier, Laurie, Dominguez, Stéphane, Augier, Romain, Sen, Sevket, Avouac, Jean-Philippe, Gallaud, Audrey, Graveleau, Fabien, Wang, Qingchen, Institut des Sciences de la Terre d'Orléans (ISTO), Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Université de Tours-Centre National de la Recherche Scientifique (CNRS), Centre de Recherches Pétrographiques et Géochimiques (CRPG), Institut national des sciences de l'Univers (INSU - CNRS)-Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS), Institut de Physique du Globe de Paris (IPGP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-IPG PARIS-Université Paris Diderot - Paris 7 (UPD7)-Université de La Réunion (UR)-Centre National de la Recherche Scientifique (CNRS), Géosciences Montpellier, Université des Antilles et de la Guyane (UAG)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Paléobiodiversité et paléoenvironnements, Muséum national d'Histoire naturelle (MNHN)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC), Division of Geological and Planetary Sciences [Pasadena], California Institute of Technology (CALTECH), Institute of Geology and Geophysics [Beijing] (IGG), Chinese Academy of Sciences [Beijing] (CAS), The French program ECLIPSE, the Chinese project kzcx3-sw-147 and 973 2005CB422101, PRA (T05-02/T06-04) and ANR financed this study, Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Université de Tours (UT)-Centre National de la Recherche Scientifique (CNRS), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Université de La Réunion (UR)-Institut de Physique du Globe de Paris (IPG Paris)-Centre National de la Recherche Scientifique (CNRS), and Muséum national d'Histoire naturelle (MNHN)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)
- Subjects
[SDU.STU.TE]Sciences of the Universe [physics]/Earth Sciences/Tectonics ,Rotation ,Erosion ,[SDE.MCG]Environmental Sciences/Global Changes ,Magnetostratigraphy ,Tian Shan ,AMS ,Sedimentology ,Uplift - Abstract
International audience; The Tian Shan Mountains constitute central Asia's longest and highest mountain range. Understanding their Cenozoic uplift history thus bears on mountain building processes in general, and on how deformation has occurred under the influence of the India-Asia collision in particular. In order to help decipher the uplift history of the Tian Shan, we collected 970 samples for magnetostratigraphic analysis along a 4571-m-thick section at the Jingou River (Xinjiang Province, China). Stepwise alternating field and thermal demagnetization isolate a linear magnetization component that is interpreted as primary. From this component, a magnetostratigraphic column composed of 67 polarity chrons are correlated with the reference geomagnetic polarity timescale between ~1 Ma and ~23.6 Ma, with some uncertainty below ~21 Ma. This correlation places precise temporal control on the Neogene stratigraphy of the southern Junggar Basin and provides evidence for two significant stepwise increases in sediment accumulation rate at ~16–15 Ma and ~11–10 Ma. Rock magnetic parameters also undergo important changes at ~16–15 Ma and ~11–10 Ma that correlate with changes in sedimentary depositional environments. Together with previous work, we conclude that growth history of the modern Tian Shan Mountains includes two pulses of uplift and erosion at ~16–15 Ma and ~11–10 Ma. Middle to upper Tertiary rocks around the Tian Shan record very young (
- Published
- 2009
33. Triassic poplyphase deformation in the Feidong-Zhangbaling massif (Eastern China) and its place in the collision between the North China and South China blocks
- Author
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Lin, Wei, Faure, Michel, Wang, Qingchen, Monié, Patrick, Department of Earth and Planetary Sciences [Kobe], Kobe University, Institut des Sciences de la Terre d'Orléans (ISTO), Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), Institute of Geology and Geophysics [Beijing] (IGG), Chinese Academy of Sciences [Beijing] (CAS), and POTHIER, Nathalie
- Subjects
Ductile deformation ,[SDU.STU.TE]Sciences of the Universe [physics]/Earth Sciences/Tectonics ,E. China ,[SDU.STU.TE] Sciences of the Universe [physics]/Earth Sciences/Tectonics ,Permian-Triassic tectonics ,Structural analysis ,Qinling-Dabie orogen - Abstract
In eastern China, the Feidong-Zhangbaling Massif is located between the Dabieshan and Sulu areas along the Tan-Lu fault. Five tectonic-metamorphic events are distinguished there. The earliest deformation (D1), corresponding to a southward compression occurred during the subduction of the South China Block below the North China Block. Top-to-the-south shearing is coeval with the Late Permian-Early Triassic blueschist facies metamorphism, and possibly with the development of south-verging recumbent folds in the Neoproterozoic-Paleozoic sedimentary cover of the South China foreland. The main ductile deformation (D2) is an extensional one, characterized by top-to-the-north shearing, coeval with the early stage of exhumation of the high-pressure rocks. A top-to-the-NW ductile shearing, and microfolds overturned to the northwest belong to a second deformation phase of exhumation (D3) which is distinct from the main event (D2). Previous 40Ar-39Ar mica dates ranging between 245 Ma and 212 Ma suggest Late Permian-Early Triassic ages for the D1 to D3 events. The D4 event produced NE-SW trending folds in the sedimentary cover interpreted as gravity collapse structures. A Late Cretaceous brittle extensional event (D5) controls the opening and infill of continental half-grabens. In the study area, the Tan-Lu fault is a Cretaceous brittle normal fault. The lack of ductile deformation along the Tan-Lu fault cannot account for the exhumation of high-pressure metamorphic rocks.
- Published
- 2004
34. Tectonic evolution of the Diabeshan and exhumation of ultra-high pressure metamorphism
- Author
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Lin, Wei, Wang, Qingchen, Faure, Michel, Shu, Liangshu S., Shärer, U., Institut des Sciences de la Terre d'Orléans (ISTO), Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), Institute of Geology and Geophysics [Beijing] (IGG), Chinese Academy of Sciences [Beijing] (CAS), Department of Earth Sciences [Nanjing], Nanjing University (NJU), and POTHIER, Nathalie
- Subjects
[SDU.STU.TE]Sciences of the Universe [physics]/Earth Sciences/Tectonics ,[SDU.STU.TE] Sciences of the Universe [physics]/Earth Sciences/Tectonics - Published
- 2003
35. Geodynamics of UHP-rock-bearing continental collision zone in central China
- Author
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Cong Bolin, Wang Qingchen, and Zhu Rixiang
- Subjects
Bearing (mechanical) ,Continental collision ,law ,Earth science ,Geochemistry ,Central china ,Geodynamics ,Geology ,law.invention - Published
- 1998
36. Recent developments in study of the typical superimposed basins and petroleum accumulation in China: Exemplified by the Tarim Basin
- Author
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Wang Qingchen and Jin Zhijun
- Subjects
geography ,geography.geographical_feature_category ,Geochemistry ,Structural basin ,Sedimentary basin ,Sedimentary depositional environment ,Tectonics ,Source rock ,Basin modelling ,Sedimentary basin analysis ,General Earth and Planetary Sciences ,Sedimentary rock ,Geomorphology ,Geology - Abstract
Most of petroliferous sedimentary basins in China have experienced multiple phases of tectonic evolution and deposition, and are characterized by tectonic and depositional superimposition. The term “superimposed basin” is suggested to describe those basins which consist of two or more simple prototype basins superimposing vertically and/or coalescing laterally. The characteristics of petroliferous superimposed basins are “multiple stages of basin forming and reworking, multiple layers of source rocks, multiple periods of hydrocarbon generation and expulsion, multiple periods of petroleum migration-accumulation-escape”. Therefore, applying the wave process analysis method to studying the process of basin formation, hydrocarbon generation, and reservoir formation, and then establishing theory of “petroleum accumulation system” is helpful to enhancing petroleum exploration efficiency in superimposed basins. This paper will, based on case study in the Tarim basin, report the major developments in studying basin formation, hydrocarbon generation and petroleum accumulation. In study of basin formation, (1) geophysical comprehensive profiles reveal that the Tarim plate has been subducted beneath the Tianshan orogenic belt with an interfinger structure and that the deep structure in the eastern section of the Tianshan orogenic belt is different from that in the western section. (2) The vertical variation in debris and geochemical composition reveals the nature and Mesozoic-Cenozoic evolution history of the Kuqa Depression. (3) Field investigation and paleostress reconstruction show that the Kuqa Depression has undergone gravity-driven extension in sedimentary cover when the Tianshan uplifted vertically. In hydrocarbon generation study, new developments include (1) setting environmental index to judge high grade source rocks in marine carbonates, and (2) establishing the lower limit of the organic carbon content for effective carbonate source rocks. In petroleum accumulation study, (1) methods of determining paleopressure and paleotemperature of forming fluid inclusions have been established. (2) The petroleum source analysis has indicated that the crude oil in the Lunnan and Tahe oilfields are derived from the source rocks of the Middle and Upper Ordovician. (3) Three generations of oil inclusions from the Lunnan oilfield have been recognized and dated.
- Published
- 2004
37. A finite difference study on the basement structure beneath the Tianshan Orogen
- Author
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Gao Xing, Wang Qingchen, Pan Shuzhen, Duan Yonghong, Zhao Junmeng, and Jia Shixu
- Subjects
geography ,geography.geographical_feature_category ,Finite difference ,Sediment ,Tarim basin ,Fault (geology) ,Structural basin ,Paleontology ,Tectonics ,Basement (geology) ,Upper crust ,General Earth and Planetary Sciences ,Geomorphology ,Geology - Abstract
We use the Pg seismic phase along the Korla-Jimsar profile across the Tianshan orogen and the 3D finite difference method to inverse the velocity structure of the upper crust beneath the basement of this mountain. Based on the velocity structure, the Korla-Jimsar profile can be divided into three parts, i.e. the north edge of the Tarim basin, the Tianshan orogen, and the south margin of the Junggar basin. Within the Tianshan there is a pattern of four convexities and three concavities, which correspond to the southern Tianshan, the Yanqi basin, the middle Tianshan, the Turpan basin, and the Bogda Mountains. In the north edge of the Tarim basin, the basement is about 10km deep with small lateral variations of velocity. In the Tianshan the velocity varies greatly laterally. The basement depth of the Yanqi basin is 6 km, which becomes shallow rapidly northward, and almost to the surface at the middle Tianshan. South to Kumux there is a small intermountain basin, where the maximum basement depth is 3 km, and also turns very shallow near Kumux. The Luntai fault, which bounds the Tarim basin and Tianshan, has vertical dislocation of about 5 km. The Turpan basin is covered with so thick a sediment that its basement is 7 km deep. The boundary fault between the Tianshan and Turpan is the Bolohoro fault which is characterized by quick deepening basement and 7 km vertical dislocation. In the Junggar basin the basement is 8 km deep. On the Korla-Jimsar profile, the velocity distribution of the upper crust and the structure are featured by NS symmetry on both sides of the axis of the Middle Tianshan, consistent with the deep structure revealed by this profile. It means that the Tarim basin and the Junggar basin underthrust toward the Tianshan from south and north, respectively. Such a structural style is different from that of another profile, i.e. the Xayar-Burjing profile, suggesting that there may be an important tectonic boundary between these two profiles.
- Published
- 2004
38. Geochronological constraint of Early Mesozoic tectonic event at Northeast Vietnam
- Author
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Chen, Zechao, Lin, Wei, Faure, Michel, Lepvrier, Claude, Yang Chu, Wang, Qingchen, State Key Laboratory of Lithospheric Evolution (SKL), Institute of Geology and Geophysics [Beijing] (IGG), Chinese Academy of Sciences [Beijing] (CAS)-Chinese Academy of Sciences [Beijing] (CAS), University Chinese Acad Science, Institut des Sciences de la Terre d'Orléans - UMR7327 (ISTO), Bureau de Recherches Géologiques et Minières (BRGM) (BRGM)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), Institut des Sciences de la Terre de Paris (iSTeP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Bureau de Recherches Géologiques et Minières (BRGM) (BRGM)
- Subjects
Song Chay belt ,[SDU.STU.TE]Sciences of the Universe [physics]/Earth Sciences/Tectonics ,Early Mesozoic ,[SDE.MCG]Environmental Sciences/Global Changes ,Tectonic evolution ,Thrust ,South margin of South China Block - Abstract
International audience; The northeastern Vietnam, northeastern Guangxi, southwestern Guangdong and Hainan Island with NW-SE trending all locate in south margin of South China Block ( SCB). It is an important region to understanding the tectonic evolution of South China Block. Song Chay belt locates in the northeast region of Vietnam, a NE-SW mineral and stretching lineation, and top-to-the-NE ductile deformation are the main structures and observed both in Early Paleozoic lower metamorphism face strata and Late Paleozoic to Early Mesozoic unmetamorphozed sedimentary rocks. These structural characteristics were coeval with N/NE verging recumbent folds and nappes. Alike for the Song Chay belt, the same Early Mesozoic structural characteristics are also observed in Yunkai terrane, Hainan island and northeast region of Guangxi. All of these deformations occurred in the same tectonic event because of the time and the deformation style are almost the same. To decipher the time of this deformation, we study the structural character of deformed strata and granitic rocks, and analyzed the high quality U-Pb zircon geochronology data, then defined the time of nappes as 237 similar to 228Ma. The geodynamic of the tectonic event can be related to the collision between South China Block and Indochina in the Early Mesozoic time. We argue that South China Block subducted beneath to Day Nui Con Voi micro-continental block along Song Chay suture zone in Early Triassic, the south margin of SCB as the subduction plate were developed top to NE thrust and NE verging nappes. This orogeny is over at Late Triassic. Therefore, the northeastern Vietnam, northeastern Guangxi, southwestern Guangdong and Hainan island are belong to the southern margin of SCB and involved in the Indosinian orogenic belt.
39. Understanding and study perspectives on tectonic evolution and crustal structure of the Paleozoic Chinese Tianshan
- Author
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Wang, Qingchen, Shu, Liangshu, Charvet, Jacques, Faure, Michel, Ma, Huadong, Natal In, Boris, Gao, Jun, Kroner, Alfred, Xiao, Wenjiao, Li, Jinyi, Windley, Brian, Yan Chen, Glen, Richard, Jian, Ping, Zhang, W., Seltmann, Reimar, Wilde, Simon, Choulet, Flavien, Wan, Bo, Quinn, Cameron, Rojas-Agramonte, Yamirka, Shang, Qinghua, Zhang, Wei, Wang, Bo, Lin, Wei, State Key Laboratory of Lithospheric Evolution (SKL), Institute of Geology and Geophysics [Beijing] (IGG), Chinese Academy of Sciences [Beijing] (CAS)-Chinese Academy of Sciences [Beijing] (CAS), Department of Earth Sciences [Nanjing], Nanjing University (NJU), Institut des Sciences de la Terre d'Orléans (ISTO), Université de Tours-Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), National 305 Project Office, ITU, Maden Fakultesi, ITU, Maden Fakultesi, Jeoloji Muhendisligi Bolumu, Institut für Geowissenschaften [Mainz], Johannes Gutenberg - Universität Mainz (JGU), Chinese Academy of Geological Sciences [Beijing] (CAGS), Ministry of Land and Resources (MLR), Department of Geology [Leicester], University of Leicester, Geological Survey of NSW, Shrimp Laboratory [Beijing], Institute of Geology [Beijing], Ministry of Land and Resources (MLR)-Ministry of Land and Resources (MLR)-Chinese Academy of Geological Sciences [Beijing] (CAGS), Ministry of Land and Resources (MLR)-Ministry of Land and Resources (MLR), Centre for Russian and Central EurAsian Mineral Studies, The Institute for Geoscience Research [Perth] (TIGeR), School of Earth and Planetary Science [Perth - Curtin university], Curtin University [Perth], Planning and Transport Research Centre (PATREC)-Planning and Transport Research Centre (PATREC)-Curtin University [Perth], Planning and Transport Research Centre (PATREC)-Planning and Transport Research Centre (PATREC), Institut des Sciences de la Terre d'Orléans - UMR7327 (ISTO), Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Bureau de Recherches Géologiques et Minières (BRGM) (BRGM), Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences [Changchun Branch] (CAS), State Key Laboratory for Mineral Deposits Research, Chinese National 973 Project no. 2009CB825008 and NSFC (40872142,90714007)., POTHIER, Nathalie, and Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Université de Tours (UT)-Centre National de la Recherche Scientifique (CNRS)
- Subjects
[SDU.STU.TE]Sciences of the Universe [physics]/Earth Sciences/Tectonics ,010504 meteorology & atmospheric sciences ,[SDU.STU.TE] Sciences of the Universe [physics]/Earth Sciences/Tectonics ,General Earth and Planetary Sciences ,010502 geochemistry & geophysics ,01 natural sciences ,0105 earth and related environmental sciences - Abstract
International audience; The Chinese Tianshan Belt is one of the key regions for the understanding of tectonics of the Central Asian Orogenic Belt (CAOB). An international field excursion and workshop were organized to conduct a common observation and discussion on the tectonic evolution of the Chinese Tianshan. This report summarizes the main achievements, including acknowledged geological features, controversial and remaining scientific problems, and discussion of a tentative geodynamic model. Thus, it is helpful to clarify what has been done in the past, what should be improved and what needs to be done in the future and therefore to better understand the tectonics of the Chinese Tianshan Belt and the CAOB as well.
40. Tectonic evolution of the Early Mesozoic Xuefengshan belt: Insights from structural analysis and geochronological constraints
- Author
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Yang Chu, Lin, Wei, Faure, Michel, and Wang, Qingchen
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