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Sulfur isotope geochemistry of the Lemachang independent Ag deposit, northeastern Yunnan——A concurrent discussion on the mechanism of sulfur isotope equilibrium between barite and freibergite below 300℃

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Chinese Science Bulletin 1999年第S2期44卷 227-230页

作者： DENG Hailin~1, LI Chaoyang~1, ZHOU Yunman~2.and WANG Congwu~2.1. Open Laboratory of Ore Deposit Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002. china 2. No.3 Braneh of no.1 Geology {2., Yunnan Bureau of Geology and Mineral Resources, xundian 655205, china Open Laboratory of Ore Deposit Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China No. 3 Branch No. 1 Geology Party Yunnan Bureau of Geology and Mineral Resources Xundian 655205 China

IN the study of hydrothermal deposits sulfur isotopes bear much information about the source of sulfur,ore-forming temperature, the evolution of ore-forming fluids and the mechanism of metallogenesis. Todetermine whether sulfur isotopes reach equilibrium between fluids and sulfur-bearing minerals precipitated from the former and among the sulfur-bearing minerals is the key to the application of sulfur isotopegeochemistry to geological problems. As it has been commonly accepted that sulfur isotopic equilibrium could not be reached between sulfate and sulfide below 350℃, little attention has been paid to thepossible mechanism of sulfur isotope equilibrium between sulfate and sulfide below 300℃. However, this note presents an example to show sulfur isotope equilibrium between barite and sulfate

关键词： sulfur isotope Lemachang independent Ag deposit barite freibergite sulfur isotope equilibrium below 300℃.

Aoyitake plagiogranite in western Tarim Block, NW china: Age, geochemistry, petrogenesis and its tectonic implications

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Science china Earth Sciences 2006年第11期49卷 1121-1134页

作者： ZHANG Chuanlin1,2. YU Haifeng3, YE Haimin2. ZHAO Yu2.& ZHANG Dongsheng4 1. Key Laboratory of Isotope Geochronology and Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, china 2. Nanjing Institute of Geology and Mineral Resources, Nanjing 2.0016, china 3. Tianjin Institute of Geology and Mineral Resources, Tianjin 300170, china 4. The 2.d Regional geological Investigation party, Xinjiang Bureau of Geology and Mineral Resources, Changji 831100, china Key Laboratory of Isotope Geochronology and Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China Nanjing Institute of Geology and Mineral Resources Nanjing China Tianjin Institute of Geology and Mineral Resources Tianjin China The 2.d Regional geological Investigation party Xinjiang Bureau of Geology and Mineral Resources Changji China

SHRIMPP U-Pb zircon age and geochemical and Nd isotopic data are reported for the Aoyitake plagiogranite in western Tarim Block, NW china. The plagiogranite intruded the Middle Pro- terozoic and Lower Carboniferous with an exposure area of ca. 60 km2.and crystallized at 330.7±4.8 Ma. Rock types mainly include tonalite, trondhjemite and minor amounts of diorite and quartz-diorite. Feldspars in the rocks are dominated by oligoclase-andesine, and minor perthite observed locally. The granites are sodic with Na/K ratios (molar) between 4 and 87. Total REE (50-2.0 ppm) show a clear positive correlation with SiO2. There is no LRRE/HREE fractionation (LaN/YbN=0.5-1.5), me- dium negative Eu anomalies (δ Eu=0.3-0.6), high Y content and low Sr/Y ratio (~1.0). These granites exhibit relatively juvenile Nd T2.M model ages of 470 to 580 Ma and positive εNd(331 Ma) values of 6.2. to 7.65. The aforementioned characteristics are similar to those of ocean island or ocean ridge plagiogranites. However, the regional geology, especially its scale, precludes that the plagiogranite pluton was derived directly from fractionational crystallization of mantle-derived basaltic magma. We interpreted that the primary magma of the pluton might be tonalitic in composition generated by ca. 50% partial melting of the juvenile basaltic crust. The primary magma experienced intensive frac- tionational crystallization, and intruded into the middle to upper crusts to form the granite pluton. In combination with the previous regional geological data, it is concluded that the plagiogranite pluton was emplaced within the Tarim Block in respond to the Carboniferous continental rifting along the Tianshan orogenic belt.

关键词： western Tarim, Aoyitake plagiogranite, age, geochemistry, tectonic implications.

Sm-Nd isotopic ages of Tiqiushan eclogites in Xinyi region and its geological significance

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Chinese Science Bulletin 1999年第S2期44卷 144-146页

作者： WANG Yinxi~(1,2., YANG Jiedong~(1,2., TAO Xiancong~(1,2., GE Ningjie~4, CHEN Peirong~3, FAN Chunfang~3 and LI Jianhua~5 1. Center of Modern Analysis, Nanjing University, Nanjing 2.0093, china 2. State Key Laboratory for Research of Mineral Deposits, Nanjing University, Nanjing 2.0093, china 3. Department of Earth Science, Nanjing University, Nanjing 2.0093, china 4. Department of Earth and Space Sciences, University of Science and Technology of Chian, Hefei 2.002., china 5. No.5 geological party of Jiangsu Province, Xuzhou 2.1005, china Center of Modern Analysis Nanjing University Nanjing 210093 China State Key Laboratory for Research of Mineral Deposits Nanjing University Nanjing 210093 China Department of Earth and Space Sciences University of Science and Technology of Chian Hefei 230026 China Department of Earth Science Nanjing University Nanjing 210093 China No. 5 geological party of Jiangsu Province Xuzhou 221005 China

geological scientists have paid much attention to the suture zones formed by collision between the Sino-Korean and Yangtze blocks because of the discovery of the ultrahigh pressue metamorphic (UHPM) rocksfrom northern Jiangsu Province (Su), southern Shandong Province (Lu) and the Dabie *** the age of 2.0-2.0 Ma is probably the best estimation for UHPM metamorphism in the DabieMountains, the primary intrusive and metamorphic ages of the complex from northern Jiangsu Provincehave not been determined before. Using the Sm-Nd isotopic dating method, our study is aimed at datingthe UHPM metanorphic event of northern Jiangsu Province and researching a probable relation between theUHPM rocks from the Dabie Mountains and the UHPM rocks from northern Jiangsu Province.

关键词： northern Jiangsu eclogite rocks Sm-Nd isotopic ages.

Sedimentary Features of Shallow Ancient River Channels on the Northern Shelf of the South china Sea

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Acta Geologica Sinica(English Edition) 1995年第1期69卷 85-98页

作者： Kou Yangqi and Du Deli 2.d Marine geological Investigation party, MGMR, Guangzhou, Guangdong Jiang M inxi 2.d Marine geological Investigation party MGMR Guangzhou Guangdong

Quaternary buried ancient river channels are widespread in the shallow-level sediments of the northern shelf of the South china Sea. The sedimentary sequence mainly of fluvial deposits comprise an important component part of the low-stand system tract and transgressive system tract in the study region. The plannar variation and spatial association of the sedimentary features such as incised valley fillings, deltaic foreset wedges and block slides of shelf-marginal fans reflect the palaeogeographic environment during the fall of the regional sea level in the northern part of the South china Sea. Based on the high-resolution seismic reflection data and gelogical data from boreholes, the present paper makes an integrated interpretation of the Quaternary ancient river channels in the shallow sediments of the study area, studies the sedimentary features of the ancient channels such as their spatial distribution, seismic facies reflection indicators, sedimentary facies and sand -body types, and discusses their formational setting and evolutionary model, with the main purpose to render a service to the hydrocarbon resources exploration and development and marine engineering in the northern shelf of the South china Sea.

关键词： Northern part of the South china Sea continental shelf shallow-buried ancient channels low-stand system tract sea level change

Vermicular fossils in the Early Cambrian Xidashan Formation in the Quruqtagh region of Xinjiang, china

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Progress in Natural Science:Materials International 2006年第5期16卷 559-562页

作者： YANG Ruidong, ZHANG Chuanlin, SONG Guoqi and LUO Xinrong (Postgraduate School of Guizhou University, Guiyang 55002., china Nanjing Institute of Geology and Mineral Resources, Nanjing 2.0016, china {2. Survey of No. 3 {2. party, Xinjiang, Kurle 841000, china) Postgraduate School of Guizhou University Guiyang 550025 China Nanjing Institute of Geology and Mineral Resources Nanjing 210016 China geological Survey of No. 3 geological {2. Xinjiang Kurle 841000 China

Large amounts of vermicular fossils and a minor amount of sponge animal fossils have been found in the Early Cambrian Xidashan Formation in the region of Quruqtagh, Xinjiang. Vermicular fossils are generally more than 50 mm long and 0. 3-1. 4 mm wide; their wrinkled lamellae are microfine with 3-10 pieces within the length of every each millimeter. The fossils are considered to be Sabellidites cambriensis Sokolov (1965) . The Xidashan Formation is the highest stratum in which Sabellidites occur, as has been so far reported.

关键词： vermicular fossil Early Cambrian Quruqtagh Xinjiang.

Re-Os dating of gold-bearing arsenopyrite of the Maoling gold deposit, Liaoning Province, Northeast china and its geological significance

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Science Bulletin 2005年第14期 103-108页

作者： YU Gang1, YANG Gang1, CHEN Jiangfeng1, QU Wenjun2. DU Andao2.& HE Wei3 1. Laboratory of Crust-Mantle Materials and Environments, School of Earth and Space Sciences, University of Science and Technology of china, Hefei 2.002., china 2. National Research Center of Geoanalysis, Chinese Academy of Geo- logical Sciences, Beijing 100037, china 3. 5th geological Survey party, Liaoning Province, Dashiqiao 115100, china

The Maoling gold deposit, one of the large gold deposits in eastern Liaoning Province, NE china, is an ar- senopyrite-disseminated gold deposit with a resource of ap- proximately 2. t Au and an average Au grade of 3.2.g/t. Six arsenopyrites closely related to Au mineralization of the Maoling gold deposit are dated by Re-Os technique and de- fine a Re-Os isochron with an age of 2.16±140 Ma, which suggests that the deposit was formed in the Paleoproterozoic era rather than in the Indosinian period as some early re- searchers suggested. High initial 187Os/188Os ratio of 1.32.0.48 indicates a crustal derivation of the ore-forming material of the deposit, which may be derived from rocks of the Gaixian formation of the Liaohe Group. Furthermore, the result also implies that the age of the Gaixian Formation in the Maoling district is older than 2.16±140 Ma.

关键词： Re-Os dating arsenopyrite Maoling gold deposit age of mineralization east of Liaoning Province.

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东海陆架多旋回复合盆地的油气远景

石油实验地质 2001年第2期23卷 141-145页

作者：李维显第一海洋地质调查大队上海201208

海礁凸起油气化探异常为其深部前新生代沉积盆地油气藏物质向上渗逸的结果。在久米 -鱼山大断裂以北的东海陆架盆地 ,除了继续探找新生代油气藏外 ,还要寻找古气新储、深源浅出的油气藏 ,这是东海油气勘探的新领域。东海大油气藏和油气... 详细信息

海礁凸起油气化探异常为其深部前新生代沉积盆地油气藏物质向上渗逸的结果。在久米 -鱼山大断裂以北的东海陆架盆地 ,除了继续探找新生代油气藏外 ,还要寻找古气新储、深源浅出的油气藏 ,这是东海油气勘探的新领域。东海大油气藏和油气田主要的气源岩可能是古生代地层。

关键词：石油天然气复合盆地陆架油气远景油气勘探东海陆架多旋回复合盆地

Discovery of Fossil Charophytes from the Late Triassic Xujiahe Formation and Early Jurassic Lower Yimen Formation, Sichuan Province, and Its Significance

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Acta Geologica Sinica(English Edition) 1992年第3期66卷 301-309,327页

作者： Liu Junying Chen Zhongliang Institute of Geology, Chinese Academy of geological Sciences, Beijing Panxi geological {2., Sichuan Bureau of Geology and Mineral Resources, Xichang Liu Linqun Institute of Geology Chinese Academy of Geological Sciences Beijing China

This paper describes the fossil charophytes collected from the Late Triassic Xujiahe Formation in Dazuand Early Jurassic Lower Yimen Formation in Xichang, Sichuan Province, and their significance. Up to now,papers dealing with fossil charophytes of the Late Triassic, especially of the Early Jurassic, have been rarelypublished. The description of the two new species of Porochara, P. dazuensis and P. xichangensis, and theirfossil assemblage not only provides an important basis for classification and correlation of red beds insouthwestern china but reveals for the first time the features of the charophyte flora of the Late Triassic-EarlyJurassic in the area, thus offering valuable data for the establishment of Triassic and Jurassic charophyte fossilzones in china.

关键词： Sichuan Late Triassic Early Jurassic charophyte fossil

An early aged ophiolite in the Western Kunlun Mountain, northwestern Tibet plateau and its tectonic implications

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An early aged ophiolite in the Western Kunlun Mountain, nort...