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Detrital Zircon U-Pb Geochronology and Lu-Hf Isotopic Compositions of the Wuliangshan Metasediment Rocks in SW Yunnan(China)and Its Provenance Implications

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Journal of Earth Science 2016年第3期27卷 412-424页

作者： Xiaowan Xing yuejun wang Yuzhi Zhang State Key Laboratory of Isotope Geochemistry Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China School of Earth Science and Geological Engineering Sun Yat-sen UniversityGuangzhou 510275China University of Chinese Academy of Sciences Beijing 100049China CAS Center for Excellence in Tibetan Plateau Earth Sciences Beijing 100101China

The Wuliangshan Group occurs to the east of the Lancang giant igneous zone in SW Yunnan, and is mainly composed of low-grade metamorphosed sedimentary rocks. The group has been considered as the syn-orogenic product of the Baoshan with Simao-Indochina blocks. However, its depositional time and provenance remain to be poorly constrained. This paper presents zircon U-Pb dating and Lu-Hf-isotopic data for five representative sandstone samples from the Wuliangshan Group. The detrital grains yield a major age-peak at ~259 Ma, and four subordinary age-peaks at ~1 859, ~941, ~788, and ~447 Ma, respectively. Our results suggest that the Wuliangshan metasedimentary sequence was deposited after Middle Triassic rather than previously-thought Cambrian. The detrital zircon age spectrum, along with in-situ Lu-Hf isotopic data suggest that the Wuliangshan Group might be a syncollisional sedimentary product related to the collision of Baoshan with Simao-Indochina blocks. It is inferred that the provenance of the Wuliangshan Group is mainly from the Simao/Yangtze blocks to the east rather than the Baoshan Block or Lancang igneous zone to the west.

关键词： detrital zircon U-Pb dating Lu-Hf isotopic composition Wuliangshan sandstone sequence Middle Triassic Simao-Indochina

The numerical simulation of a new double swirl static mixer for gas reactants mixing

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Chinese Journal of Chemical Engineering 2020年第9期28卷 2438-2446页

作者： Zhuokai Zhuang Jingtian Yan Chenglang Sun Haiqiang wang yuejun wang Zhongbiao Wu Key Laboratory of Environment Remediation and Ecological Health Ministry of EducationCollege of Environmental&Resources ScienceZhejiang UniversityHangzhou310058China Zhejiang Provincial Engineering Research Centre of Industrial Boiler&Furnace Flue Gas Pollution Control Hangzhou 310058China College of Control Science and Engineering Zhejiang UniversityHangzhou 310027China Zhejiang Tianlan Environmental Protection Technology Co.Ltd Hangzhou 311202China

For the nitrogen oxide removal processes,high performance gas mixer is deeply needed for the injection of NH3 or *** this study,a new type of double swirl static mixer in gas mixing was investigated using computational fluid dynamics(CFD).The results obtained using Particle Image Velocimetry(PIV)correlated well with the results obtained from *** comparisons in pressure loss between the experimental results and the simulation results showed that the model was suitable and accurate for the simulation of the static *** process conditions and design were *** L/D equaled 4,coefficient of variation(COV)was<5%.The inlet velocity did not affect the distributions of turbulent kinetic *** terms of both COV and pressure loss,the inner connector is important in the design of the static *** nozzle length should be set at 4 *** both COV and pressure loss into consideration,the optimal oblique degree is *** averaged kinetic energy changed according to process conditions and *** new static mixer resulted in improved mixing performance in a more compact *** new static mixer is more energy efficient compared with other SV static ***,the double swirl static mixer is promising in gas mixing.

关键词： CFD PIV Gas mixing Double swirl static mixer Pressure loss

METTL7A-mediated m6A modification of corin reverses bisphosphonates-impaired osteogenic differentiation of orofacial BMSCs

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International Journal of Oral Science 2024年第3期16卷 528-538页

作者： Yizhou Jin Xiao Han yuejun wang Zhipeng Fan Beijing Key Laboratory of Tooth Regeneration and Function Reconstruction Beijing Stomatological HospitalSchool of StomatologyCapital Medical UniversityBeijingChina Beijing Laboratory of Oral Health Capital Medical UniversityBeijingChina Research Unit of Tooth Development and Regeneration Chinese Academy of Medical SciencesBeijingChina

Bisphosphonate-related osteonecrosis of jaw(BRONJ)is characterized by impaired osteogenic differentiation of orofacial bone marrow stromal cells(BMSCs).Corin has recently been demonstrated to act as a key regulator in bone development and orthopedic ***,the role of corin in BRONJ-related BMSCs dysfunction remains unclarified.A m6A epitranscriptomic microarray study from our group shows that the CORIN gene is significantly upregulated and m6A hypermethylated during orofacial BMSCs osteogenic *** knockdown inhibits BMSCs osteogenic differentiation,whereas corin overexpression or soluble corin(sCorin)exerts a promotion ***,corin expression is negatively regulated by bisphosphonates(BPs).Corin overexpression or sCorin reverses BPs-impaired BMSCs differentiation ***,we find altered expression of phos-ERK in corin knockdown/overexpression BMSCs and BMSCs under sCorin ***98059(a selective ERK inhibitor)blocks the corin-mediated promotion *** regard to the high methylation level of corin during osteogenic differentiation,we apply a non-selective m6A methylase inhibitor,Cycloleucine,which also blocks the corin-mediated promotion ***,we demonstrate that METTL7A modulates corin m6A modification and reverses BPs-impaired BMSCs function,indicating that METTL7A regulates corin expression and thus contributes to orofacial BMSCs differentiation *** conclude,our study reveals that corin reverses BPs-induced BMSCs dysfunction,and METTL7A-mediated corin m6A modification underlies corin promotion of osteogenic differentiation via the ERK *** hope this brings new insights into future clinical treatments for BRONJ.

关键词： impaired cor mediated

K-Ar dating of late Mesozoic volcanism and geochemistry of volcanic gravels in the North Huaiyang Belt, Dabie orogen: Constraints on the stratigraphic framework and exhumation of the northern Dabie orthogneiss complex

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Chinese Science Bulletin 2002年第20期47卷 1688-1695页

作者： yuejun wang Weiming Fan Feng Guo Chinese Acad Sci Guangzhou Inst Geochem Guangzhou 510640 Peoples R China

Two eruption episodes are identified through systematic field investigations and K-Ar dating of the late Mesozoic volcanic rocks in the North Huaiyang belt (NHB), Dabie orogenic belt, of which the earlier volcanic suite termed Maotanchang Fm. (Fm.) occurring at Jinzhai, Xianhualing and Maotanchang, etc., was erupted from 149 Ma to 138 Ma. The other named Xiaotian Fm. mainly distributed at Xiaotian, Shucheng, etc., was formed between 132 Ma and 116 Ma. During the eruption gap of the two volcanic suites deposited a volcano-sedimentary conglomerate layer, which are composed of the multi-compositional gravels, including the North Dabie orthogneiss complex (NDOC), volcanic gravels, etc. These volcanic gravels in the conglomerate layer show identical geochemical and isotopic compositions (87Sr/86Sr(t) =0.7084-0.7092,εNd(t) =-21.8--24.4) to the Maotanchang Fm. volcanic rocks (87Sr/86Sr = 0.7086-0.7102,εNd = -19.2-24.4), but significantly distinct from those of Xiaotian Fm. (87Sr/86Sr = 0.7076-0.7084, εNd=

关键词： multi-gravel conglomerate layer K-Ar dating geo-chemical comparison late Mesozoic uplifting-erosion North Huai-yang belt.

Dynamics of unstable continental subduction:Insights from numerical modeling

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Science China Earth Sciences 2017年第2期60卷 218-234页

作者： HUANGFU PengPeng wang yuejun FAN WeiMing LI ZhongHai ZHOU YongZhi School of Earth Science and Geological Engineering Sun Yat-sen University Key Laboratory of Computational Geodynamics College of Earth SciencesUniversity of Chinese Academy of Sciences CAS Center for Excellence in Tibetan Plateau Earth Sciences Key Laboratory of Continental Collision and Plateau UpliftInstitute of Tibetan Plateau ResearchChinese Academy of Sciences

Numerical experiments are used in this study to systematically investigate the effects of convergence rate,crustal rheological strength,and lithospheric thermal structure on the dynamics of continental *** study focuses on the types,conditions and processes of unstable continental *** results suggest that the development of unstable continental subduction can be promoted by conditions that tend to decrease rheological strength of the lithosphere,such as low crustal rheological strength,"hot"thermal structure of the lithosphere,or low convergence *** subduction mode can be further categorized into three types:(1)multi-stage slab breakoff,(2)continuously"flowing"of fluid-like slab into the upper mantle,and(3)large-scale detachment of the thickened orogenic *** three types of unstable continental subduction are respectively associated with(1)a low convergence rate,(2)"hot"thermal structure of the lithosphere with a high convergence rate,and(3)moderate-high crustal rheological strength with a low convergence *** is also revealed that the evolution of crustal melting is dominated by the deformation pattern of continental collision,which is mainly controlled by crustal rheological *** modelling results have important implications for understanding of continental subduction mode selection under specific geodynamic conditions.

关键词： Unstable continental subduction Stable continental subduction Slab breakoff Detachment Partial melting

Prototethyan orogenesis in southwest Yunnan and Southeast Asia

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Science China Earth Sciences 2022年第10期65卷 1921-1947页

作者： yuejun wang Xianghong LU Xin QIAN Sainan WU Yuzhi ZHANG Yang wang Guangdong Key Lab of Geodynamics and Geohazards School of Earth Sciences and EngineeringSun Yat-sen UniversityZhuhai 519082China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai 519082China

The Prototethyan Ocean has been suggested as an Early Paleozoic Ocean developed at the Gondwana northern margin. However, its spatial pattern, subduction style and closure time in SW Yunnan and SE Asia still remain unknown. The Prototethyan evolution in SW Yunnan and SE Asia and its internal connection with the South China Kwangsian(Ordo-Silurian)intracontinental orogenesis are also poorly constrained. By summarizing and analyzing the Early Paleozoic geological records in the Sibumasu and Indochina blocks, the eastern South China and SW Japan, this paper proposes the existence of a giant OrdoSilurian igneous belt along the Gondwana northern margin. A preliminary limitation has been obtained regarding the source nature and migration pattern of the igneous belt. Our data allow us to propose a model of the Early Paleozoic Andean-type active continental margin along the East Gondwana northern margin. This is the foundation to determine the southward subduction of the southern branch of the eastern Prototethyan Ocean underneath the Sibumasu and Indochina blocks along the YunxianMenghai(SW Yunnan)-Thailand Peninsula and the Tam Ky-Phouc Son suture in Central Vietnam, respectively, and the eastward linkage with the Early Paleozoic Osaka subduction zone in SW Japan across the peripheral Sanya area. These data synthetically indicate an easterly-diachronous and propagating Andean-type Cambrian(Furongian)-Silurian(Llandovery) orogenesis along the Gondwana northern margin from Nepal, NW India, South Tibet, Qiangtang to Central Vietnam across South Indochina and Sibumasu. This paper reconstructs the Early Paleozoic locations of the Sibumasu and Indochina fragments, as well as SW Japan and South China continent in the Gondwana northern margin, and proposes the far-field effect on the South China Kwangsian intra-continental orogenesis from the subduction of the Early Paleozoic Prototethyan southern branch.

关键词： Igneous rocks Sedimentary sequence Early Paleozoic Prototethyan southern branch ocean Andean-type orogenesis SW Yunnan and SE Asia

Zircon U-Pb Geochronology of the Cenozoic Granitic Mylonite along the Ailaoshan-Red River Shear Zone:New Constraints on the Timing of the Sinistral Shearing

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Journal of Earth Science 2016年第3期27卷 435-443页

作者： Xiaofei Guo yuejun wang Huichuan Liu Jianwei Zi State Key Laboratory of Isotope Geochemistry Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China University of Chinese Academy of Sciences Beijing 100049China School of Earth Science and Geological Engineering Sun Yat-sen UniversityGuangzhou 510275China CAS Center for Excellence in Tibetan Plateau Earth Sciences Beijing 100101China School of Earth and Environment University of Western AustraliaCrawley 510275Western Australia

The Ailaoshan-Red River（ASRR） shear zone in SW China represents an important discontinuity believed to have accommodated eastward extrusion of the Tibetan Plateau in response to the collision of the Indian and Eurasian plates. The onset timing and duration of the ASRR sinistral strike-slip shearing have been hotly disputed. In this paper we present new zircon LA-ICP-MS U-Pb geochronological data from six syntectonic granitic mylonite and leucosomes samples from the ASRR shear zone. Our data reveal a metamorphic age of ~40 Ma, most likely suggesting the maximum age of the shearing initiation. Rocks showing syn-kinematic signatures yield crystallization ages of 38–22 Ma, with inherited components ranging from 716 to 108 Ma. These results, together with existing geological and geochronological data, indicate that the sinistral shearing along the ASRR zone probably began at 40 Ma, mainly activated at 29–22 Ma and lasted at least to ~22 Ma. Our data suggest a continuous extrusion between the Indochina and South China blocks during ~35–17 Ma. The ASRR sinistral shearing has accommodated large scale eastward displacement of the southeastern Tibetan syntaxis, and is likely responsible for the opening of the South China Sea.

关键词： Ailaoshan-Red River zircon U-Pb dating mylonite and migmatite sinistral shearing eastward extrusion

Petrogenesis for the Chiang Dao Permian High-Iron Basalt and Its Implication on the Paleotethyan Ocean in NW Thailand

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Journal of Earth Science 2016年第3期27卷 425-434页

作者： Yuzhi Zhang yuejun wang Boontarika Srithai Burapha Phajuy School of Earth Science and Geological Engineering Sun Yat-sen UniversityGuangzhou 510275China CAS Center for Excellence in Tibetan Plateau Earth Sciences Beifing 100101China Department of Geological Sciences Faculty of ScienceChiang Mai UniversityChiang Mai 50200Thailand

The Changning-Menglian suture in SW Yunnan has been accepted as the Paleotethyan main ocean. However, it has been a matter of debate as to its southerly extension in NW Thailand（the Chiang Mai-Chiang Rai vs. Nan-Uttaradit zone）. Our field investigation identified the high-iron basaltic rocks in the Chiang Dao Permian standard profile in NW Thailand. The high-iron rocks provide crucial records for understanding the controversy on the location of Paleotethyan main ocean in NW Thailand. The Early Permian high-iron samples show extremely high Fe Ot（20.96 wt.%–25.56 wt.%） and TiO2（6.07 wt.%–6.34 wt.%） and low SiO2（38.54 wt.%–43.46 wt.%） and Mg O（1.61 wt.%–2.40 wt.%） contents. Such characteristics are similar to those of the Fenner differentiation trend rarely observed in the natural system, distinct from those of the ＂normal＂ Bowen trend. Their chondrite- normalized REE and primitive mantle-normalized patterns are generally similar to those of typical OIB. The initial 87Sr/86 Sr ratios and εNd（t） values range from 0.704 677 to 0.705 103 and 3.16 to 3.48, respectively, falling near the field of typical OIB（oceanic-island basalt）. These data synthetically suggest that the Chiang Dao high-iron rocks are the products of high-degree partial melting of peridotite with Fe-rich eclogitic blobs/streaks in response to a seamount setting. In comparison with the Permian tectonic setting in SW Yunnan and NW Thailand, it is inferred that the Paleotethyan Ocean was located between the Shan-Thai terrane of Sibumasu and Sukhothai arc along the Inthanon zone of the Chiang Mai-Chiang Rai rather than Nan-Uttaradit zones.

关键词： high-iron rock Fenner differentiation trend Chiang Dao OIB-like basalt Paleotethyan Ocean seamount setting

Petrogenesis and tectonic implications of Early Cretaceous andesitic-dacitic rocks,western Qinling(Central China):Geochronological and geochemical constraints

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Geoscience Frontiers 2019年第4期10卷 1507-1520页

作者： Feifei Zhang Peter A. Cawood Yunpeng Dong yuejun wang State Key Laboratory of Continental Dynamics Department of GeologyNorthwest UniversityXi’an 710069China Department of Earth Sciences University of St.AndrewsNorth StreetSt.Andrews KY16 9ALUK School of Earth Atmosphere and EnvironmentMonash UniversityMelbourneVictoria 3800Australia Guangdong Provincial Key Lab of Geodynamics and Geohazards School of Earth Sciences and EngineeringSun Yat-sen UniversityGuangzhou 510275China

40Ar/39Ar and zircon U-Pb geochronological and whole-rock geochemical analyses for the Laozanggou intermediate-acidic volcanic rocks from the western Qinling orogenic belt,Central China,constrain their petrogenesis and the nature of the Late Mesozoic lithospheric *** volcanic rocks yield hornblende or whole-rock 40Ar/39Ar plateau ages of 128.3-129.7 Ma and zircon U-Pb age of131.3±1.3 *** exhibit SiO2 of 56.86-66.86 wt.%,K2 O of 0.99-2.46 wt.%and MgO of 1.03-4.47 wt.%,with Mg#of *** are characterized by arc-like geochemical signatures with significant enrichment in LILE and LREE and depletion in *** the samples have enriched Sr-Nd isotopic compositions with initial 87Sr/86Sr ratios ranging from 0.7112 to 0.7149 andεNd(t)values from 10.2 to *** geochemical signatures suggest that these volcanic rocks were derived from enriched lithospherederived magma followed by the assimilation and fractional crystallization(AFC)*** generation of the enriched lithospheric mantle is likely related to the modification of sediment-derived fluid in response to the Triassic subduction/collision event in Qinling orogenic *** early Cretaceous detachment of the lithospheric root provides a reasonable mechanism for understanding the petrogenesis of the Laozanggou volcanic sequence in the western Qinling orogenic belt.

关键词： 40Ar/39Ar and zircon U-Pb geochronology Sr-Nd isotopes Early Cretaceous AFC process Continental lithospheric mantle Western Qinling orogenic belt