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Chinese Science Bulletin 1996年第8期41卷 667-670页

作者：赵崇贺何科昭莫宣学邰道乾叶德隆叶栴林培英毕先梅郑伯让冯庆来 China University of Geosciences Beijing 100083 China

Metamorphic basement is widespread in northeastern Jiangxi Province withcomplicated geological structure and enriched polymetallic deposits. It is one of the impor-tant areas for geological research in China, especial... 详细信息

关键词： northeastern Jiangxi deep fault belt ophiolitic melange late Paleozoic radiolarian.

Geochemistry of the Late Paleozoic radiolarian cherts within the NE Jiangxi ophiolite melange and its tectonic significance

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Science China Earth Sciences 2000年第6期43卷 617-624页

作者：李献华 Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China

Major and trace elements are presented for the late Paleozoic radiolarian cherts, which were spatially associated with the NE Jiangxi ophiolite melange. These chert samples show relatively low SiO2 (78.40%-89.28%) and high AI2O3 (3.42%-11.02%). Low Si/AI ratios (6.3-23) and tight negative correlation between Si/Al and AI2O3 of the samples indicate that they are muddy cherts containing high and variable contents of pelitic detritus. Geochemically, they are characterized by AI2O3/(AI2O3+Fe2O3) = 0.51-0.90, shale-normalized Lan/Cen = 0.76-1.11, Ce/Ce’ = 0.91-1.22, V40, resembling those of cherts formed in the continental margin regimes. It is therefore concluded that these late Paleozoic radiolarian muddy cherts were most likely formed in a continental margin regime, and not genetically related to the ophiolite suite in NE Jiangxi. It is also unlikely that an oceanic basin existed between the Yangtze and Cathaysia blocks during the late Paleozoic.

关键词： cherts element geochemistry ophiolite melange NE Jiangxi.

An ophiolitic tectonic melange first discovered in Huashan area, south margin of Qinling Orogenic Belt, and its tectonic implications

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Science China Earth Sciences 1999年第3期42卷 292-302页

作者：董云鹏张国伟赖绍聪周鼎武朱炳泉

On the basis of the synthetic studies of geology and geochemistry, an ophiolitic tectonic melange was discovered in Sanligang-Sanyang area, the western part of Xiangfan-Guangji fault, the south margin of the Qinling Orogenic Belt. It is composed of different tectonic blocks with different lithological features and ages, mainly including the Huashan ophiolite blocks, Xiaofu Island-arc volcanic blocks, pelagic sediments, fore-arc volcanic-sedimentary system, and the massif of the basement and the covering strata of the Yangtze Block. These massifs were emplaced in the western part of Xiangfan-Guangji fault, the boundary between the Qinling Orogenic Belt and Yangtze Block, contacting each other by a shear zone or chaotic matrix. The characteristics of geochemistry indicate that the basalts of the Huashan ophiolite are similar to mid-oceanic ridge basalts (MORB) formed in an initial oceanic basin, and the Xiaofu volcanic rocks are formed in a tectonic setting of island arc. The ophiolitic tectonic melange

关键词： Qinling Orogenic Belt Xiangfan-Guangji fault Huashan ophiolitic tectonic melange suture zone oceanic basin.

Origin of the serpentinites in the Lichi melange,eastem Taiwan,China:implication from petrology and geochronology

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China Geology 2018年第4期1卷 477-484页

作者： Long Huang Wei Geng Zhi-lei Sun Qingdao Institute of Marine Geology Qingdao 266071China Laboratory for Marine Mineral Resources Qingdao National Laboratory for Marine Science and TechnologyQingdao 266071China The Key Laboratory of Gas Hydrate Ministry of Land and ResourcesQingdao 266071China

Lichi melange,located in the southern coastal range,eastern Taiwan,China,is a typical tectonic melange of the plate's boundary zone between the Eurasian Plate and the Philippine Sea Plate.It formed during the collision of the Luzon arc with the Eurasian Continent (arc-continent collision).It is composed of sandstone and/or mudstone matrix and many kinds and sizes of rock fragments,including some sedimentary rocks,volcanic rocks and a few metamorphic rocks.The serpentinite is one of the common fragments in the Lichi melange.By the petrographic characteristics and the zircon U-Pb chronology analyses,protolith of the serpentinite is peridotite,the age is 17.7 ±0.5 Ma.Taking the tectonic background into account,it is inferred that the serpentinite (serpentinised peridotite)come from the forearc basin (the North Luzon Trough)and was taken into the melange by a second thrust westwards.The origin of the serpentimte in Lichi melange is helpful to understand the formation of the Lichi melange and can provide reliable detailed information for the study of the arc-continent collision orogenic activity in and offshore Taiwan.

关键词： Lichi melange Serpentinite Arc-continent collision Taiwan U-Pb geochronology

Origin and Emplacement of Archean Ophiolites of the Central Orogenic Belt, North China Craton

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Journal of Earth Science 2010年第5期21卷 744-781页

作者： Timothy M Kusky 李江海 State Key Laboratory for Geological Processes and Mineral Resources China University of Geosciences Three Gorges Research Center for Geohazards Ministry of Education China University of Geosciences School of Earth and Space Sciences Peking University

Understanding Archean crustal and mantle evolution hinges upon identification and characterization of oceanic lithosphere. We report and update here more than 10 years work on a complete, yet dismembered and metamorphosed Archcan ophiolite sequence in the North China craton, in the Dongwanzi （东湾子）-Zunhua （遵化） structural belt and correlatives in the Wutaishan （五台山） area. Banded iron formation structurally overlies several tens of meters of variably deformed pillow lavas, mafic flows, and picritic amphibolites. These are in structural contact with a 2 km thick mixed gabbro and dike complex with gabbro screens, exposed discontinuously along strike for more than 20 km. The dikes consist of metamorphosed diabase, basalt, Hb-Cpx-gabbro, and pyroxenite. The dike/gabbro complex is underlain by several kilometers of mixed isotropic and foliated gabbro, which preserve compositional layering approximately 2 km below the dike complex, and then over several hundred meters merge into strongly compositionally layered gabbro and olivine-gabbro. The layered gabbro becomes mixed with layered pyroxenite/gabbro marking a transition zone into emulate ultramaflc rocks including serpentinzed dunite, pyroxenite and wehrlite, and finally into strongly deformed and serpentinized olivine and orthopyroxene-bearing ultraInafic rocks interpreted as depleted mantle harzburgite tectoultes. A U/Pb zircon age of 2.505 Ga from gabbro of the Dongwanzi ophioUte makes it one of the world＇s oldest recognized, laterally. extensive complete ophiolite sequences, though older dismembered ophiolites are recognized in South Africa and Greenland, extending back to 3.8 Ga. This age is confirmed by a ca. 2.6 Ga Re-Os isochron from chromites from the belt, and a number of dated 2.5-2.4 Ga cross-cuttlng younger igneous units. The Dongwanzi ophiolite is one of the largest well-preserved greenstone belts in the central orogenic belt that divides the North China craton into eastern and western blocks. More than 1 000 other fragments of gabbro, pillow lava, sheeted

关键词： North China craton Archcan ophiolite Proterozoic melange podiform chromite.

Geochemistry of ophiolite cherts from the Qinling orogenic belt and implications for their tectonic settings

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Science China Earth Sciences 2004年第4期47卷 329-337页

作者： ZHANG Chengli1, 2, GAO Shan1, 3, ZHANG Guowei1, GUO Anlin1, YUAN Honglin1, LIU Xiaoming1 & WANG Jianqi1 1. The key Laboratory of Continental Dynamics, Ministry of Education, Department of Geology, Northwest University, Xian 710069China 2. State Key Laboratory for Mineral Deposits Research, Nanjing University, Nanjing 210093, China 3. Department of Geochemistry, China University of Geosciences, Wuhan 430074, China The key Laboratory of Continental Dynamics Ministry of Education Department of Geology Northwest University Xi’an China State Key Laboratory for Mineral Deposits Research Nanjing University Nanjing China Department of Geochemistry China University of Geosciences Wuhan China

Paleozoic cherts from the Mianl黣 and the Erlangping ophiolite zones of the Qinling orogenic belt are characterized by low Si/Al ratios (52.14-683.52 in the Mianle cherts, 12.29-58.62 in the Erlangping cherts), Fe2O3 (0.01-0.35 and 0.02-1.24) and high Al2O3/(Al2O3+Fe2O3) ratios (0.82-0.99 and 0.83-0.99). The negative correlation between Si2O and Al2O3 in the cherts reflects the important role of terrigenous components. The Erlangping cherts have Lan/Cen=0.9-1.15 and Ce/Ce*=0.95-1.15 with low contents of V, Ni and Cu, consistent with those of cherts forming on the continental margin. In contrast, the Ce/Ce* ratios of the Mianle cherts range from 0.71 to 1.18 and Lan/Cen from 0.88 to 1.43 with slightly high V, Ni and Cu, which are similar to cherts found in the mid-ocean ridges and pelagic basins. Combined with the features of basic lavas associated with the cherts, it is suggested that during the Paleozoic, when the back-arc basin represented by the Erlangping ophiolite commenced shrinking in size in the mid-Ordovician, the southern Qinling was still in an extensional regime and finally grew into a new limited oceanic basin in the early Carboniferous.

关键词： Qinling orogenic belt, radiolarian cherts, ophiolite melange zone.

New paleontological evidence on time determination of the east part of the Eastern Kunlun Mélange and its tectonic significance

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Science China Earth Sciences 2004年第10期47卷 865-873页

作者： ZHANG Kexin LIN Qixiang ZHU Yunhai YIN Hongfu LUO Mansheng CHEN Nengsong WANG Guocan Faculty of Earth Science China University of Geosciences Wuhan 430074 China Faculty of Earth Science China University of Geosciences Wuhan 430074 China Faculty of Earth Science China University of Geosciences Wuhan 430074 China Faculty of Earth Science China University of Geosciences Wuhan 430074 China Faculty of Earth Science China University of Geosciences Wuhan 430074 China Faculty of Earth Science China University of Geosciences Wuhan 430074 China Faculty of Earth Science China University of Geosciences Wuhan 430074 China

New paleontological evidence suggests that the composition of the matrix and slices from the middle and the south of the Eastern Kunlun Mélange Belt is very complex, ranging from Proterozoic to Mesozoic in geological time. A Cambrian acritarch assemblage has been discovered from the middle part of the Eastern Kunlun Mélange, a Neoproterozoic to the early Paleozoic acritarch assemblage has been discovered from the south of the Eastern Kunlun Mé lange, and so has been an Early Permian radiolarian from the A’nyemaqen Mélange in Buqing- shan. In addition, some sporopollen has been obtained from the Mesozoic tectonic slices. The above-mentioned paleontological evidence indicates that the Eastern Kunlun Orogenic Belt experienced two episodes from ocean to continent from the Neoproterozoic to the Early Paleo- zoic and in the Late Paleozoic respectively. In the process of intracontinent development in Mesozoic, because of heavy thrust-nappe, strike-slip sheer and crust shortening, the Mesozoic formation was intercalated in mélange by slices and the Eastern Kunlun Orogenic Belt became more complex.

关键词： Eastern Kunlun melange Belt, paleobio-assemblage, time determination, geotectonic evolution.

STRUCTURAL FEATURES AND EVOLUTION OF THE NADANHADA TERRANE

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Science China Chemistry 1992年第5期35卷 621-630页

作者：邵济安唐克东王成源臧启家张允平 Peking University Beijing 10087 PRC. Shenyang Institute of Geology and Ministry of Geology and Mineral Resources Shenyang 110032 PRC. Nanjing Institute of Geology and Palaeontology Academia Sinica Nanjing 210008 PRC.

The study of terranes has already become an important subject in research of the Circum-Pacific continental margin. This paper discusses proper understanding of the terrane conception and identifies existence of the Nadanhada terrane according to its difference from the neighbouring massifs in terms of evolutionary history, tectonic background, and deformation features, and to the fault-contact relation between them; analyzes the paleogeographic position variation of the Nadanhada terrane during the Triassic to late Jurassic and the period when the terrane was attached to the ancient continental marging; finally discusses the consequential effects of theterrane accretion from the observed tectonic events after terrane collage.

关键词： terrane radiolarian palaeolatitude melange collage.

YAMDROK melange,SOUTH TIBET

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地学前缘 2000年第S1期7卷 127-127页

作者： Liu Jianbing 1, J.C.Aitchison 1, Badengzhu 2, A.M.Davis 1, S.V.Ziabrev 1, Luo Hui 1, I.McDermid 1(1 Tibet Research Group, Dept. of Earth Sciences, University of Hong Kong, Hong Kong SAR, China 2 Geological Team No.2, Tibetan Bureau of Geology

Yamdrok melange occurs south of, and parallel to, the Yarlung—Zangbo ophiolites, extending several hundreds of kilometres with a width of several to tens of kilometres. Areas near Baisa and Rilang in the Gyangze district were chosen for detailed investigation in this study. Three months of field mapping (1∶1000 and 1∶50000) has been followed by laboratory investigation to extract radiolarians from cherty blocks and matrix material. Laboratory work is continuing..Field investigations in the Baisa area near Gyangze indicate the presence of three melange facies:broken formation, matrix\|rich facies, and block\|in\|matrix melange. Broken formation is characterized by disruption of layering by means of boudinage and pinching\|and\|swelling and dispersal of blocks within the finer\|grained shales due to layer\|parallel extension. Broken formation occurs mostly as dispersed but more\|or\|less traceable lenses within a foliated matrix. A transition from broken formation to typical block\|in\|matrix melange is observed in the field. Further disruption of broken formation leads to the formation of typical block\|in\|matrix melange either, by later shearing, or by suspected mud diapirism. Matrix\|rich facies is characterized by a dominance of shale matrix containing small granules of sandstone and other lithologies. This facies commonly is subject to later deformation, with disruption of the primary foliation into sigmoidal structures. Block\|in\|matrix facies is the most common melange facies and is characterized by blocks of different sizes, shapes and lithologies either encased in, or floating on, relatively finer\|grained arenaceous\|argillaceous matrix. Blocks range in size from several centimeters to several hundreds of meters, and have various shapes from phacoidal, elongate, to irregular. The blocks are mainly composed of varicolored cherts, greywacke and limestone as well as igneous rocks including serpentinite and basalt breccia. The matrix is mainly composed of dark argillaceous shales and siliceous shales, and p

关键词： Yamdrok melange South Tibet melange facies broken formation matrix\|rich facies block\|in\|matrix Radiolaria

THE ROCK ASSOCIATION IN JINSHAJIANG melange BELT

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地学前缘 2000年第S1期7卷 126-126页

作者： Lin Shiliang (Chengdu Institute of Geology and Mineral Resources,Chengdu 610082,China)

Jinshajiang melange belt locates between Jianda\|Weixi island arc and Zhongzha massif. The melange belt and island arc makes up Jinshajiang plate junction. Although subsequent tectonic movements had complexed the structural form of Jinshajiang melange belt, there are still a lots of structural block remained which carried amount of information about the tectonic evolution of the belt. Recent researches have identified several kinds of rock association in the structural blocks.(1) Ophiolite:The ophiolite consists of serpentinization ultramafite, ultramafic cumulus crystal rock (pyroxenite, dunite), gabbro, diabase cluster, ocean\|ridge type basalt, plagiogranite and radiolarian silicalite. The isotopic age shows that the ultramafite and basalt formed during Upper Carboniferous and Lower Permian. The silicalite is high in radiolaria of Lower Permian.(2) Rock association of oceanic island\|arc:The liptocoenosis of oceanic island\|arc scatter in melange belt, it mainly consists of sandy slate, pyroclastic rock, silicalite, basalt and andesite. A part of volcanic rock belongs to calc\|alkaline volcanic suite and the other is tholeiite. The petrochemistry, REE and microelement of volcanic rock have the feature of the rock in ocean\|island arc. The isotopic age of basalt shows that the ocean\|island arc formed in Lower Permian.

关键词： rock association Jinshajiang melange belt ophiolite structura l blocks