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A new species of the genus Hyla(Amphibia:Anura:Hylidae)from the Dabie Mountains,Anhui,China 被引量:1
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作者 Cai-Wen Zhang Yong Zhang +6 位作者 Yin-Fan Cai Lei Yu Da-Peng Pang Qing-Yue Jiang Jun Ding Da-Jie Gong Bao-Wei Zhang 《Zoological Research(Diversity and Conservation)》 2025年第1期42-54,共13页
Hyla tsinlingensis(Hu et al.,1966)is endemic to China,and is widely distributed in the Qinling and Dabie Mountains.Previous studies have suggested that genetic differentiation and geographical isolation exist between ... Hyla tsinlingensis(Hu et al.,1966)is endemic to China,and is widely distributed in the Qinling and Dabie Mountains.Previous studies have suggested that genetic differentiation and geographical isolation exist between the Qinling Mountains population and Dabie Mountains population of H.tsinlingensis,and that the Dabie Mountains population is a cryptic species.Several Hyla specimens were collected from the Dabie Mountains of western Anhui Province,China during herpetological surveys from 2022‒2024;these specimens belonged to a species previously identified as H.tsinlingensis.Herein,we utilized phylogenetic analyses,morphological comparisons,and advertisement call comparisons,revealing significant differences from those of other known congeners;thus,we describe them as a new species.The discovery of this species implies that there are currently 18 identified species in the genus Hyla,7 of which are found in China. 展开更多
关键词 dabie Mountains Hyla dabieshanensis sp.nov. Hyla tsinlingensis Taxonomy Morphology
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Petrology of Eclogite at Huwan,Western Dabie and Implications for Phase Equilibrium Modeling on LT-HP/UHP Eclogite
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作者 Bin Xia Ying Cui +1 位作者 Yunfeng Shang Jingtao Shi 《Journal of Earth Science》 2025年第3期1018-1032,共15页
Phase equilibrium modeling using internally consistent thermodynamic dataset and associated activity-composition(a-x)models are very helpful for quantifying P-T evolution for eclogite,which is the basis for decipherin... Phase equilibrium modeling using internally consistent thermodynamic dataset and associated activity-composition(a-x)models are very helpful for quantifying P-T evolution for eclogite,which is the basis for deciphering the geodynamic processes in subduction zones.In this study,we apply different versions of datasets(ds55 and ds62)and associated a-x relations to a wellestablished LT-HP eclogite at Huwan in the classic western Dabie orogen to constrain its P-T evolution.The eclogite comprises garnet+omphacite+amphibole+white mica+epidote+quartz+chlorite+rutile/ilmenite/sphene.Garnet porphyroblasts show mono-variation in the end members(spessartine from 17 mol%to 0,pyrope from 2 mol%to 18 mol%,almandine from 47 mol%to 64mol%and grossular from 35 mol%to 18 mol%)from core to rim.Phase diagrams combined with compositional isopleth thermobarometry show that dataset ds62 and associated a-x relations yield P_(max)of~33 kbar at~560℃,conflicting with our petrological observations and previous studies.On the other hand,phase equilibrium modeling using dataset ds62 and a revised symmetric garnet a-x model irrespective of Fe^(3+)(O)gives P_(max)of~27 kbar at~560℃,consistent with the results using dataset ds55 and associated a-x relations.Therefore,we recommend a symmetric model for garnet involving py,alm,gr and spss,without Fe~(3+)components,instead of the asymmetric garnet a-x relations involving py,alm,gr,spss and kho by White et al.(2014),for calculating phase diagrams for LT-(U)HP eclogite when using dataset ds62.In this study,the defined P-T path is characterized by a segment of the prograde evolution showing a first moderate slope,followed by gentle then steep slopes,representing the thermal structure evolution recorded by slab surface during continental subduction.Our work combined with previous studies conclude that in western Dabie,the Huwan HP eclogite belt to the north and the Hong'an HP eclogite belt to the south belong to the same HP slice overlying the Xinxian UHP slice. 展开更多
关键词 phase equilibrium modeling LT-HP eclogite continental subduction western dabie garnets PETROLOGY
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Origins of Two Types of Serpentinites from Hong'an,Western Dabie Orogen,Central China and Associated Fluid/Melt-Rock Interactions:Implications from Geochemistry and Mineralogy
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作者 Yuchen Liu Changqian Ma 《Journal of Earth Science》 2025年第3期992-1017,共26页
A cluster of serpentinite bodies has been recognized tectonically emplaced within the greenschist-amphibolite-facies metamorphic terrane in Hong'an,western Dabie orogen,central China.Two types of serpentinites are... A cluster of serpentinite bodies has been recognized tectonically emplaced within the greenschist-amphibolite-facies metamorphic terrane in Hong'an,western Dabie orogen,central China.Two types of serpentinites are identified on the basis of integrated petrographic,mineralogical and geochemical study.The first type,represented by Yinshanzhai serpentinite complex(Group 1)comprises heterogeneous lithology as a massive serpentinite matrix“intruded”by antigoriteenriched serpentinite lenses.They are both pseudomorphic textured with different mineral assemblages indicating an increasing temperature-pressure condition.Serpentinite matrix(Group 1a)is chemically characterized by high MgO/SiO_(2)and low Al_(2)O_(3)/SiO_(2),Ti and Ca contents,suggesting a depleted mantle wedge origin.The coexistence of compositionally-heterogeneous chromite with highCr^(#)(0.78-0.96)and intermediate-Cr^(#)(0.59-0.70)pristine cores indicates extensive mantle melting.Meanwhile,extremely high Fo olivine relicts(96-97)with considerably higher MnO and lower NiO contents than mantle olivine indicate that they are metamorphic products from serpentine decomposition.Accordingly,we propose that Yinshanzhai serpentinite complex experienced two distinct episodes of hydration.The serpentinite lenses(Group 1b)show higher SiO_(2)and lower MgO concentrations.Nevertheless,the trace elements of groups 1a and 1b are consistent:U-shaped REE patterns,positive Eu anomalies and enrichment of LILE(i.e.,Cs,U)are all identified as forearc properties.They are affected by reducing slab-derived fluids in forearc mantle,with f_(O2)of 1 to 2 logarithmic units below f_(O2)of fayalite-magnetite-quartz buffer(FMQ-2~FMQ-1).The second type is antigorite-serpentinites(Group2)represented by Ximaoshan and Wangchunwan blocks.They are non-pseudomorphic,with no primary framework silicate surviving.Fertile compositions(i.e.,higher Al_(2)O_(3)and Al_(2)O_(3)/SiO_(2),nearly flat REE patterns)and conjoint enrichment of LILE with HFSE suggest melt/rock interaction.Negative Ce,Eu anomalies,and enriched U relative to alkaline elements demonstrate interactions with more oxidized seawater or seafloor fluids(FMQ~FMQ-1).Remarkable Sr negative anomalies may be attributed to Sr release during lizardite/antigorite transition in subduction zone,indicating interaction with low-Sr slab fluids.We propose that Group 2 serpentinites originate either from mantle wedge or abyssal peridotites,refertilized by mantle melts,then hydrated in seafloor or shallow forearc and entrapped into subduction channel.Combined with geochronology and tectonic constraints of associated eclogites in Hong'an terrane,the two types of serpentinites may correlate with subduction of different oceanic basins during the late Paleozoic and/or Proterozoic eras.It raises possibility of defining an ophiolitic setting in Hong'an Orogen for which further evidence is required. 展开更多
关键词 SERPENTINITES orogenic peridotites western dabie chromite fluid/melt-rock interaction GEOCHEMISTRY MINERALOGY
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Magnetotelluric imaging of the northern margin of the Dabie orogenic belt:implications for thermal structure
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作者 Wangqi Ren Guoqiang Xue +1 位作者 Weiying Chen Tao Chen 《Applied Geophysics》 2025年第4期899-909,1491,共12页
To explore the high heat flow anomalies from the Dabie orogenic belt,We have set up 15 Magnetotelluric(MT)stations.The stations have an average spacing of~2 km.Firstly,the phase tensor method is used to analyze MT dat... To explore the high heat flow anomalies from the Dabie orogenic belt,We have set up 15 Magnetotelluric(MT)stations.The stations have an average spacing of~2 km.Firstly,the phase tensor method is used to analyze MT data to estimate the dimensional characteristics of the underground resistivity structure.Then,based on the results of dimensional characteristics analysis,three-dimensional(3D)inversion was performed using ModEM,and a 3D resistivity structure from the surface to a depth of 30 km was obtained.It shows:that there are extensive low resistivity anomalies in the lower crust of the northern margin of the Dabie orogenic belt,which may be partial melting or water-bearing fluid.The high heat flow anomaly in the northern margin of the Dabie orogenic belt may be due to the increase of the background heat flow value caused by the orogenic belt delamination during post-collision,the thinning of the lithosphere and the upwelling of the asthenosphere. 展开更多
关键词 dabie orogenic belt MAGNETOTELLURIC 3D inversion Heat flow
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Unveiling the role of social networks: Enhancing rural household livelihood resilience in China's Dabie Mountains
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作者 TANG Lanyun LIU Chongchong WANG Ying 《Journal of Geographical Sciences》 2025年第2期335-358,共24页
Social networks are vital for building the livelihood resilience of rural households.However,the impact of social networks on rural household livelihood resilience remains em-pirically underexplored,and most existing ... Social networks are vital for building the livelihood resilience of rural households.However,the impact of social networks on rural household livelihood resilience remains em-pirically underexplored,and most existing studies do not disaggregate social networks into different dimensions,which limits the understanding of specific mechanisms.Based on 895 household samples collected in China's Dabie Mountains and structural equation modeling,this paper explored the pathway to enhance livelihood resilience through social networks by dis-aggregating it into five dimensions:network size,interaction intensity,social cohesion,social support,and social learning.The results indicate that:(1)Livelihood assets,adaptive capacity and safety nets significantly contribute to livelihood resilience,whereas sensitivity negatively affects it.Accessibility to basic services has no significant relationship with livelihood resilience in the study area.(2)Social networks and their five dimensions positively impact livelihood re-silience,with network support having the greatest impact.Therefore,both the government and rural households should recognize and enhance the role of social networks in improving liveli-hood resilience under frequent disturbances.These findings have valuable implications for mitigating the risks of poverty recurrence and contributing to rural revitalization. 展开更多
关键词 livelihood resilience social network rural revitalization structural equation modeling dabie Mountains China
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Magmatic Processes of the Lingshan Granitic Batholith in the Dabie Orogen,Central China:Insights into Dabie-Type Porphyry Mo Mineralization
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作者 Jiang Zhu Zhanke Li +5 位作者 Guohu Wang Xianbin Shi Yang Wang Chao Chen Song Chen Yuanbing Zou 《Journal of Earth Science》 2025年第5期2075-2093,共19页
Dabie-type porphyry Mo deposits were proposed as a new type of porphyry Mo deposits,and had unique geological characteristics.It is still poorly understood about the magmatic processes that led to the Dabie-type Mo mi... Dabie-type porphyry Mo deposits were proposed as a new type of porphyry Mo deposits,and had unique geological characteristics.It is still poorly understood about the magmatic processes that led to the Dabie-type Mo mineralization.Here,we present zircon U-Pb and Lu-Hf isotopic,whole-rock and biotite elemental,and whole-rock Sr-Nd isotopic analyses on the Lingshan granitic batholith in the Dabie Orogen.It consists of three units(ⅠtoⅢ)that were emplaced before,genetically accompanied with,and after the Mo mineralization.LA-ICP-MS zircon U-Pb dating yielded crystallization ages of 128.2±1.0 Ma(MSWD=1.14)for UnitⅠand ages of 127.8±1.2 Ma(MSWD=0.28)and 126.6±1.8 Ma(MSWD=1.6)for UnitⅡ,indicating that they were emplaced during 130 to 125 Ma.The granites have high SiO_(2)contents(75.84 wt.%to 78.94 wt.%)and low MgO contents(0.07 wt.%to 0.10 wt.%),and are classified as fractionatedⅠ-type granite.UnitsⅠandⅡhave similar Sr-Nd isotopic ratios(ε_(Nd)(t)=-16.2 to-17.2,(^(87)Sr/^(86)Sr)_(i)=0.70540 to 0.70692)and zirconε_(Hf)(t)values(-17.4 to-20.4),indicating they were derived from partial melting of the ancient Yangtze lower crust.Mo mineralized granite from UnitⅡis characterized by the lower oxygen fugacity,fluorine enrichment and high fractionation.Magmas of unitsⅠandⅡhave experienced fractional crystallization,with the assimilation of supracrustal materials that account for the increased TiO_(2),F and Mo contents,and the decreased fO_(2).We proposed that the assimilation in upper-crustal magmatic processes plays key factors for magmatic systems that led to the Dabie-type porphyry Mo deposits. 展开更多
关键词 granite crustal assimilation oxygen fugacity porphyry Mo deposit dabie Orogen mineral deposits
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Location of Triassic Tectonic Suture Between Collided Sino-Korean and Yangtze Cratons in Dabie-Sulu Region, China 被引量:11
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作者 Suo Shutian Zhong Zengqiu You Zhendong(Faculty of Earth Sciences, China University of Geosciences, Wuhan 430074) 《Journal of Earth Science》 SCIE CAS CSCD 1999年第4期281-286,共6页
The regional extent and spatial distribution of ultrahigh pressure metamorphic(UHPM) and high pressure metamorphic (HPM) rocks, and the geometrical relationships of various petrotectonic units in the Dabie-Sulu region... The regional extent and spatial distribution of ultrahigh pressure metamorphic(UHPM) and high pressure metamorphic (HPM) rocks, and the geometrical relationships of various petrotectonic units in the Dabie-Sulu region indicate that the Triassic collisional suture line between the Sino-Korean and Yangtze cratons is situated at the northern margin of the Dabie massif, that is,along the Balifan-Mozitan-Xiaotian fault in the Dabie region, and possibly is linked to the Wulian-Yantai fault in the Sulu region to tbe east. The suture line has been strongly modified duriug and subsequent to UHPM aud HPM events. 展开更多
关键词 UHPM and HPM belts suture line dabie massif dabie-Sulu region
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A Uniform Orogen-parallel Extension System of the Shear Zones in the Tongbai-Dabie Orogenic Belt, Central China 被引量:3
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作者 LIU Huan LIN Shoufa SONG Chuanzhong 《Acta Geologica Sinica(English Edition)》 CAS CSCD 2018年第2期556-567,共12页
Large-scale magmatism affected the Tongbai-Dabie orogenic belt during post-collisional lateral tectonic extension in the Cretaceous, which was suggested to account for the widespread deformation and migmatization in t... Large-scale magmatism affected the Tongbai-Dabie orogenic belt during post-collisional lateral tectonic extension in the Cretaceous, which was suggested to account for the widespread deformation and migmatization in the Tongbai-Dabie complexes. However, it cannot explain the most deformations in the shear zones. The northwest-southeast shear zones are developed around or wrapped the Tongbai-Dabie complexes. They play an important role for the interpretation of the tectonic evolution of the Tongbai-Dabie orogenic belt. By a systematically observation and description of the geometry and kinematics of these shear zones, we found that the shear zones to the north dip NE and have a uniform sinistral shear sense, the shear zone to the south dips SW and has a uniform dextral shear sense, and the shear zones at the core are sub-horizontal and have a uniform top-to-NW sense of shear. Combining with the comparison of previous and our geochronological studies, we interpret these associations as indicating that these shear zones were originally a single, more flat-lying and sub- horizontal shear zone with a uniform top-to-NW shear sense before the folding-doming of the Tongbai- Dabie complexes and suggest that the Tongbai-Dabie orogenic belt experienced a uniform top-to-NW orogen-paraUel extension in the ductile lithosphere before the widespread magmatism in the Cretaceous. 展开更多
关键词 Tongbai-dabie orogenic belt shear zone Tongbai complex dabie complex orogen-parallel extension
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Multi-Layered Low-Angle Ductile Detachment System in Dabie-Sulu UHPM and HPM Belts, China 被引量:2
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作者 Suo Shutian Zhong Zengqiu(Faculty of Earth Sciences, China University of Geosciences, Wuhan 430074) 《Journal of Earth Science》 SCIE CAS CSCD 1999年第3期187-193,共7页
The present-day observed crustal-scale tectonic style of ultrahigh-pressure metamorphic (UH-PM) and high-pressure metamorphic (HPM ) belts in the Dabie-Sulu region was dominantly formedby extensional processes, postda... The present-day observed crustal-scale tectonic style of ultrahigh-pressure metamorphic (UH-PM) and high-pressure metamorphic (HPM ) belts in the Dabie-Sulu region was dominantly formedby extensional processes, postdating the Triassic collision between the Sino-Korean and Yangtze cratons. The extensional structures overprinting the previous structures related to contraction that produced the thickened continental crust of the UHPM and HPM belts, in particular display the typical features of a Cordilleran-type metamorphic core complex, in which at least four regionalscale, low-angle ductile shear zones that constitute a detachment system, are recognized in the Dabie region. In the Sulu region, the extensionaI structures show in the form of small-scale domes or a regional-scale SE-dipping pseudo-monocline. The geometry and the kinematics of tbe detachment zones are briefly described and their significance for the exhumation of UHPM and HPM rocks is discussed. It is iniliated that the subhorizontal crustal-scale extensional flow in the middle-lower crust, under amphibolite- to greenschist-facies conditions, was an important tectonothermal process at 200- 170 Ma and the exhumation or the UHPM and HPM rocks was achieved at least in part along multi-layered detachment zones. The regional detachment system has been the main factor enabling UHPM and HPM rocks to be brought from middle-lower crustal levels to middle-upper crustal levels. 展开更多
关键词 detachment system UHPM and HPM rocks exhumation ductile shear zone dabie massif dabie-Sulu region
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The Basic Indexes and Practices of Regional Ecological Agricultural Construction in Dabie Mountains——A Case Study of Huanggang,Hubei
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作者 鲍宏礼 鲁丽荣 《Agricultural Science & Technology》 CAS 2017年第4期740-743,共4页
Taking Huanggang city as an example, the requirements of basic indexes for the regional ecological agricultural construction in Dabie Mountains were ana- lyzed and the measures that must be taken in implementing the i... Taking Huanggang city as an example, the requirements of basic indexes for the regional ecological agricultural construction in Dabie Mountains were ana- lyzed and the measures that must be taken in implementing the in the Dabie Mountains were proposed. 展开更多
关键词 dabie Mountains Huanggang Basic indexes of ecological agricultural construction
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即将发作的Dabi病毒的诊治与免疫
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作者 郭钧锋 范荣 《电子与电脑》 1994年第4期18-20,共3页
计算机病毒在国内的传播和发展已有近十年的历史了。从引导型、文件型、混合型,到一年前出现的DOS内核型病毒DIR—2,呈现出一种由简单到复杂,并逐渐深入DOS内核的发展趋势,其隐蔽性也逐渐加强,发现和防治的难度不断加大。 我们最近发现... 计算机病毒在国内的传播和发展已有近十年的历史了。从引导型、文件型、混合型,到一年前出现的DOS内核型病毒DIR—2,呈现出一种由简单到复杂,并逐渐深入DOS内核的发展趋势,其隐蔽性也逐渐加强,发现和防治的难度不断加大。 我们最近发现了一种隐蔽性很强的新病毒。由于它传染了一个具有自身防护能力的解病毒程序,致使该程序无法运行,从而偶然发现了该病毒的存在。 展开更多
关键词 计算机病毒 诊治 dabi病毒
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DABI(1465)病毒的原理及诊治
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作者 郭书军 《电脑技术——Hello-IT》 1996年第9期23-23,共1页
关键词 计算机病毒 诊治 dabi病毒
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Petrology, Metamorphic Process and Genesis of The Dabie--Sulu Eclogite Belt, Eastern--Central China 被引量:17
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作者 Zhang Zeming You Zhendong Han Yujing and Sang Longkang Department of Earth Sciences, China University of Geosciences, Wuhan, Hubei 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1996年第2期134-156,共23页
The Qinling-Dabie-Sulu high-pressure and ultra-high pressure metamorphic belt wasformed by subduction and collision between the North China and Yangtze plates. The study ofthe eclogite belt is very important in unders... The Qinling-Dabie-Sulu high-pressure and ultra-high pressure metamorphic belt wasformed by subduction and collision between the North China and Yangtze plates. The study ofthe eclogite belt is very important in understanding the evolution of the Qinling Dabie orogen. Inthe present paper the geology, petrology, minerology and chronology of the eclogites in the Dabieand Sulu areas are described. The principal conclusions of this work are as follows: (1) Based up-on the field occurrence and the P-T conditions of the eclogites, two types of eclogite can be dis-tinguished: Type 1—the low-temperature and high-pressure eclogite in the mid-late Proterozoicmetamorphic series, and Type 2—the ultra-high pressure eclogite in the late Archaean to earlyProterozoic metamorphic complex. In the Dabie area, the ultra-high-pressure eclogite,high-pressure eclogite and epidote-blueschist units are nearly parallel to each other and stretchintermittently from north to south. (2) The P-T conditions of the high-pressure eclogites and ul-tra-high pressure eclogites have been estimated. The former are formed at 450-550℃ and1.4-1.6 GPa; while the latter at 650-870℃ and >2.7-2.9 GPa in the Dabie area and at820-1000℃ and >2.8-3.1 GPa in the Sulu area. The metamorphic temperatures of the eclogitesincrease progressively from west to east. (3) The ultra-high pressure eclogites were subjected to 5stages of metamorphism: pre-eclogite epidote amphibolite facies, peak coesite eclogite facies,post-eclogite amphibolite facies, epidote-blueschist facies or epidote amphibolite facies andgreenschist facies. The general features of the PTt path of the ultra-high pressure eclogite are:clockwise pattern, progressive metamorphism being a process of slow increasing temperature andrapid increasing pressure, and the retrogressive section with nearly isothermal decompression atthe early stage, isobaric cooling at the middle stage and nearly isothermal decompression at thelate stage. (4) At least two stages of high-pressure metamorphism occurred in the orogenic belt:the high-pressure eclogite and ultra-high pressure eclogite were formed by the subduction of theoceanic crust northward beneath the North China plate or the Dabie block during theCaledonian; while the epidote-blueschist belt came into being by subdution and collision be-tween the two continental plates during the Indosinian. (5) Due to the continuous sequentialsubduction of the cold plate, the ultra high-presssure metamorphic rocks were uplifted to thecrust by the underplating processes. They can be preserved just because of the 'frozen effect' re-sulting from the continuous subduction of the cold plate. (6) The carbonates, such as magnesite,breunnerite, aragonite and dolomite, and the H_2O-bearing minerals, such as phengite, epidoteand zoisite, were stable during the high-pressure and/or ultra-high pressure metamorphism. 展开更多
关键词 PETROLOGY mineral chemistry chronology PTt—path dabie—Sulu eclogite belt east—central China
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^(207)Pb/^(206)Pb Zircon Dating of the Huangtuling Hypersthene-Garnet-Biotite Gneiss from the Dabie Mountains, Luotian County, Hubei Province, China: New Evidence for Early Precambrian Evolution 被引量:11
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作者 JIAN Ping YANG Weiran and ZHANG Zichao Institute of Geology,CAGS,26 Baiwanzhuang Rd, Beijing 100037 China University of Geosciences, Wuhan, Hubei 430074 Yichang Institute of Geology and Mineral Resources, CAGS, Yichang, Hubei 443003 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1999年第1期78-83,127-128,共8页
The Huangtuling hypersthene-garnet-biotite gneiss at Luotian County, Hubei Provine, is a typicalgranulite-facies rock of the Dabie Group Complex in the Dabie orogenic belt. Investigations on the morphology andoccurren... The Huangtuling hypersthene-garnet-biotite gneiss at Luotian County, Hubei Provine, is a typicalgranulite-facies rock of the Dabie Group Complex in the Dabie orogenic belt. Investigations on the morphology andoccurrence of zircons and their internal structures shown in the thin sections lead to the recognition of three types ofzircons, which are in good agreement with the types identified on the basis of morphology, colour and external fea-tures from the related zircon concentrates. The observation of zircons in the rock reveals that part of type 1 zirconsshow signs of a double-layered structure. The interval part existed in the protolith prior to the granulite-facies meta-morphism. Type 2, the prismatic zircons which mainly occur in garnet and hypersthene are metamorphic minerals ofthe granulite-facies metamorphism. Type 3, the round multifaceted zircons in felsic minerals and biotite, are proba-bly attributed to a later geological event related to migmatization. The ^(207)Pb/^(206)Pb zircon dating by direct evaporationon (thermal evaporation ion mass spectrometer) yields ages ranging from 2814 Ma to 1992 Ma. The age discrepancyamong these different zircon types is conspicuous. The yellow-brown(type 1) zircons give ages of 2814±29 Ma to2527±6 Ma, the prismatic euhedral zircons (type 2), 2456±7 Ma to 2254±4 Ma, and the round multifaceted zircons(type 3), 1992±10 Ma. The results are geologically interpreted in consideration of the complicated behaviours of zir-cons during Precambrian geological evolution of the Dabie area. (1) If the protolith of the gneiss is a sedimentaryrock, then type 1 zircons are clastic ones and the ages 2814±29 Ma and 2811±27 Ma may reflect the minimum age ofthe rocks of its source region. also the first geological event in the area. Sedimentation of the protolith occurred be-tween 2814 Ma and 2527 Ma, probably close to 2814 Ma. If the protolith is a volcanic rock, then the formation age ofthe supracrustal rocks of the Dabie Group Complex is around 2814 Ma. The age 2456±7 Ma reflects the time whenthe granulite-facies metamorphism took place. The later migmatization event is dated at aboat 1992±10 Ma, and isprobably the latest early Precambrian event in the area. The present work provides geochronological evidence for the existence of the Dabie Archaean craton, whichhad probably experienced 3 or 4 geological events during its early Precambrian evolution. 展开更多
关键词 dabie Mountains granulite facies ARCHAEAN multistage evolution ZIRCON 207~Pb/206~Pb
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Thermal Evolution of the Tanlu Fault Zone on the Eastern Margin of the Dabie Mountains and Its Tectonic Implications 被引量:14
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作者 ZHUGuang HOUMinjin +2 位作者 WANGYongsheng LIUGuosheng NIUManlan 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2004年第4期940-953,共14页
Five samples of muscovite from mylonites of the earlier Tanlu ductile shear zone on the eastern margin of the Dabie Mountains yield 40Ar/39Ar ages ranging from 178 Ma to 196 Ma. Three of them have reliable plateau age... Five samples of muscovite from mylonites of the earlier Tanlu ductile shear zone on the eastern margin of the Dabie Mountains yield 40Ar/39Ar ages ranging from 178 Ma to 196 Ma. Three of them have reliable plateau ages of 188.7±0.7 Ma, 189.7±0.6 Ma and 192.5±0.7 Ma respectively, which indicates a syn-orogenic, sinistral strike-slip thermal event. This displacement movement derived from the continent-continent collision of the North and South China blocks took place in the Early Jurassic and after uplifting of high-pressure to ultrahigh-pressure slabs to the mid-crust. It is suggested that during the collision the Tanlu fault zone was an intracontinental transform fault caused by differential subduction speeds. The 40Ar/39Ar ages of mylonite whole-rock and muscovite from the later Tanlu ductile shear zone suggest another sinistral strike-slip cooling event at 128 Ma. During this strike-slip faulting, large-scale intrusion and doming uplift occurred in the eastern part of the Dabie orogenic belt. Data of K-feldspar 40Ar/39Ar MDD and apatite fission-track analysis from metamorphic rocks indicate two high-speed cooling events experienced by the Tanlu fault zone, which took place at 90 Ma and 45-58 Ma respectively. They correspond respectively to two phases of extensional activities in the Late Cretaceous and Eogene as well as development of the Qianshan fault-controlled basin to the east of the Tanlu fault zone. The cooling times recorded by K-feldspar and apatite show that the uplifting in the Dabie orogenic belt occured earlier than that on the eastern margin occupied by the Tanlu fault zone. The above phenomena suggest that the uplifting of the Dabie orogenic belt during the Late Cretaceous to Eogene was not controlled by the Tanlu normal faulting, but as a result of the lithospheric delamination. 展开更多
关键词 Tanlu fault zone dabie orogenic belt 40Ar/39Ar age fission-track age thermal event
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Zircon Geochronological Evidence for Participation of the North China Craton in the Protolith of Migmatite of the North Dabie Terrane 被引量:10
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作者 Haijin Xu Junfeng Zhang 《Journal of Earth Science》 SCIE CAS CSCD 2018年第1期30-42,共13页
The plate affiliation of the North Dabie terrane (NDT) has been controversial. To address this fundamental question, an integrated study of internal structure, in-situ U-Pb dating and trace element analysis in zirco... The plate affiliation of the North Dabie terrane (NDT) has been controversial. To address this fundamental question, an integrated study of internal structure, in-situ U-Pb dating and trace element analysis in zircons and field investigation for migmatite in the NDT was carried out, which reveals par- ticipation of crustal rocks of the North China Craton (NCC) in the protolith in addition to the more common crustal rocks of the Yangtze Craton (YC). The evidence of an NCC affinity for protolith of migmatite in the NDT is the -2.5 Ga (2 486±14 and 2 406±26 Ma) magamtic age and -1.8 Ga (1 717±79 Ma) metamorphic age in the relict zircon domains because these two age groups are characteristic for the evolution of the NCC. The evidence of a YC affinity for protolith of migmatite in the NDT is the more common 0.7-0.8 Ga (e.g., 787±12 Ma) magamtic zircon age. Mid-Neoproterozoic magmatic age (0.7-0.8 Ga) is a symbol of YC basement rocks. In view of the widely exposed YC crustal components in the NDT, we suggest that the protolith of the NDT is mainly crustal rocks from the YC with minor crustal components from the NCC. The zircon rim domains and new growth grains from all the migmatite sam- ples are characterized by anatectic zircons and have a widely concordant ages ranging from 112.2±2.8 to 159.6±4.3 Ma with several peak values, suggesting a long lasting multistage anatexis. In conclusion, the NDT has a mixed protolith origin of both the YC and the NCC crustal rocks were strongly remoulded by anatexis during orogenic collapse. 展开更多
关键词 North dabie terrane MIGMATITE zircon U-Pb age PROTOLITH tectonic affinity.
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Geochemical Characteristics and Genesis of the Granitic Gneisses from the Southeastern Dabie Mountains 被引量:9
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作者 薛怀明 董树文 刘晓春 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2001年第2期175-183,共9页
The granitic gneisses from the ultrahigh-pressure (UHP) metamorphic terrain of the southeastern Dabie Mountains encompass two types: monzonitic granitic gneiss and alkali-feldspar granitic gneiss, which are characteri... The granitic gneisses from the ultrahigh-pressure (UHP) metamorphic terrain of the southeastern Dabie Mountains encompass two types: monzonitic granitic gneiss and alkali-feldspar granitic gneiss, which are characterized by rich alkalis, poor CaO, high FeO/MgO, particularly high Ba, Rb, Th, Ta, REE (except Eu), Ga, Nb and Zn, and low Sr, Eu, Cr, Co and Ni. The gneisses, particularly the alkali-feldspar granitic gneiss, have typical chemical characteristics of A-type granites. They resulted from partial melting of crustal materials existing in the rift zone along the northern margin of the South China block during the Neoproterozoic. These gneisses might not have undergone UHP metamorphism during the late Triassic, but were involved into UHP rocks by the tectonic mixing process and kept the exhumation message of the UHP rocks from the middle and upper crust. 展开更多
关键词 granitic gneiss A-type granite UHP complex PROTEROZOIC dabie Mountains
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Convective Initiation by Topographically Induced Convergence Forcing over the Dabie Mountains on 24 June 2010 被引量:9
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作者 Qiwei WANG Ming XUE Zhemin TAN 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2016年第10期1120-1136,共17页
The initiation of convective cells in the late morning of 24 June 2010 along the eastward extending ridge of the Dabie Mountains in the Anhui region, China, is studied through numerical simulations that include local ... The initiation of convective cells in the late morning of 24 June 2010 along the eastward extending ridge of the Dabie Mountains in the Anhui region, China, is studied through numerical simulations that include local data assimilation. A primary convergence line is found over the ridge of the Dabie Mountains, and along the ridge line several locally enhanced convergence centers preferentially initiate convection. Three processes responsible for creating the overall convergence pattern are identified. First, thermally-driven upslope winds induce convergence zones over the main mountain peaks along the ridge, which are shifted slightly downwind in location by the moderate low-level easterly flow found on the north side of a Mei-yu front. Second, flows around the main mountain peaks along the ridge create further convergence on the lee side of the peaks. Third, upslope winds develop along the roughly north-south oriented valleys on both sides of the ridge due to thermal and dynamic channeling effects, and create additional convergence between the peaks along the ridge. The superposition of the above convergence features creates the primary convergence line along the ridge line of the Dabie Mountains. Locally enhanced convergence centers on the primary line cause the initiation of the first convection cells along the ridge. These conclusions are supported by two sensitivity experiments in which the environmental wind (dynamic forcing) or radiative and land surface thermal forcing are removed, respectively. Overall, the thermal forcing effects are stronger than dynamic forcing given the relatively weak environmental flow. 展开更多
关键词 dabie Mountains convective initiation low-level convergence line thermal forcing dynamic forcing
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A New Species of the Genus Rhacophorus (Anura: Rhacophoridae) from Dabie Mountains in East China 被引量:8
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作者 Tao PAN Yanan ZHANG +9 位作者 Hui WANG Jun WU Xing KANG Lifu QIAN Kai LI Yu ZHANG Jinyun CHEN Dingqi RAO Jianping JIANG Baowei ZHANG 《Asian Herpetological Research》 SCIE CSCD 2017年第1期1-13,共13页
A new species of rhacophorid of the genus Rhacophorus is described from the Dabie Mountains of west Anhui, east China. The new species, Rhacophorus zhoukaiyae sp. nov. is distinguished from its congeners by a combinat... A new species of rhacophorid of the genus Rhacophorus is described from the Dabie Mountains of west Anhui, east China. The new species, Rhacophorus zhoukaiyae sp. nov. is distinguished from its congeners by a combination of the following characters: 1) the ventral surface and front-and-rear of the femur is paler yellowish and decorated with irregular grayish blotching, and without obvious spots on the dorsum of the hand and foot webbing; 2) the outer metatarsal tubercle is small; 3) outer fingers are half-webbed and outer toes two third webbed; 4) the skin on the dorsum is smooth and without compressed warts; 5) the throat, chest and belly are pure paler yellowish; 6) the dorsal part of the fingers and toes are grayish-white; 7) the iris is golden-yellow. In addition, the phylogenetic tree showed that all the individuals of R. zhoukaiyae sp. nov. clustered into one distinct clade which suggested the validity of this species. This results could also be used to the support of species delimitation. Currently, this species is known only from mid-elevation montane evergreen forest in the Dabie Mountains of west Anhui, China. 展开更多
关键词 Rhacophorus Rhacophorus zhoukaiyae sp. nov. PHYLOGENY Rhacophoridae dabie Mountains
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A New Species of the Genus Tylototriton(Amphibia: Urodela: Salamandridae) from the Southern Dabie Mountains in Anhui Province 被引量:8
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作者 Lifu QIAN Xiaonan SUN +7 位作者 Jiaqi LI Weibo GUO Tao PAN Xing KANG Hui WANG Jianping JIANG Jun WU Baowei ZHANG 《Asian Herpetological Research》 SCIE CSCD 2017年第3期151-164,共14页
A new species of the genus Tylototriton is described,from Yuexi county,Anhui province,in the south of the Dabie Mountains.It is based on morphological and molecular analysis.The new species is identified as belonging ... A new species of the genus Tylototriton is described,from Yuexi county,Anhui province,in the south of the Dabie Mountains.It is based on morphological and molecular analysis.The new species is identified as belonging to the Tylototriton asperrimus group and shares a number of similarities with T.wenxianensis,T.broadoridgus and T.dabienicus.The diagnostic characteristics of the new species are as follows: the head length is greater than the width of the head; bony ridges on the head are prominent and necked-in; the distal digit ends,ventral digits,peripheral area of the cloaca and the tail's lower edge are orange.The result from the molecular analysis of the genus Tylototriton(including the type specimen of the new species) based on three mitochondrial genes(ND1,ND2 and CYTB) indicated that the new species was close to T.wenxianensis,T.dabienicus,and T.broadoridgus,but formed an independent clade.This result was consistent with the morphological analysis above,which supports the theory that the population distributed in the south of the Dabie Mountains,namely in from Yuexi county,Anhui province,represented a distinct species,Tylototriton anhuiensis sp.nov. 展开更多
关键词 new species Tylototriton anhuiensis sp. nov. southem dabie Mountains taxonomy morphology molecular analyses
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