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Cosmogenic ^(21)Ne concentrations and exposure ages of summit bedrocks in the Grove Mountains,Antarctica

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Science china Earth Sciences 2010年第4期53卷 518-521页

作者： KONG Ping1,2,DING Lin2,LAI QingZhou2 & HUANG FeiXin3.1 Key Laboratory of the Earth’s Deep Interior,institute of geology and Geophysics,Chinese Academy of Sciences,Beijing 100029,china 2 Key Laboratory of Continental Collision and Plateau Uplift,institute of Tibetan Plateau Research,Chinese Academy of Sciences,Beijing 100085,china 3.institute of mineral resources Research,china Metallurgical geology Bureau,Beijing 100025,china Key Laboratory of the Earth’s Deep Interior Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China Key Laboratory of Continental Collision and Plateau Uplift Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing China institute of mineral resources Research China Metallurgical Geology Bureau Beijing China

Various sources of 21Ne and 22Ne exist in surface rocks:cosmogenic,in situ nucleogenic from internal U and Th,trapped crustal nucleogenic and trapped *** paper reports the first measurement,in china,of cosmogenic 21Ne and 22Ne in surface *** developed a unique sample pre-treatment procedure that effectively removed inclusions inside quartz grains,and thus maximally reduced nucleogenic contributions of 21Ne and ***-heating experiments show that concen-trations of cosmogenic 21Ne and 22Ne in summit bedrock samples R9202 and R9203.from Grove Mountains,Antarctica,are(3.83.0.87)×108 and(5.22±0.51)×108 atoms/g,*** corresponding minimum exposure ages are 2.2±0.5 and 3.0±0.3.*** indicates that the ice sheet in East Antarctica was uncovered the crest of Mount Harding,a typical nunatak in Grove Mountains,since at least mid-Pliocene.

关键词： 21Ne cosmogenic nuclide exposure age Antarctica Grove Mountains

Archaean Greenstone Belts in china

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Acta Geologica Sinica(English Edition) 1994年第1期68卷 15-29页

作者： Shen Baofeng, Peng Xiaoliang, Luo Hui and Mao DebaoTianjin institute of geology, Ministry of geology and {3. resources, Tianjin Tianjin institute of geology Ministry of Geology and Mineral Resources Tianjin 1Other participants in the study include Jin Wenshan Hu Xiaodie Li Shuangbao and Li Junjian.

Chinese Achaean greenstone belts are mainly distributed along the northern and southwestern margins of the North china platform. In terms of their geological characteristics, the greenstone belts in china are comparable to those in other countries but at the same time have unique features of their own. In view of their geochemistry, the Chinese greenstone belts may be grouped into three types: the Jiapigou type, Qingyuan type and Xiaoqinling type. The greenstone belts were formed possibly in a rift-type palaeo-tectonic setting, similar to that of the modern island are-continental margin mobile belts.

关键词： Archaean greenstone belts types of greenstone belts rift type tectonic setting china

Changes of infrared absorption wave number of aromatic-ring C=C bond of vitrinite and their significance

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Chinese Science Bulletin 1998年第12期43卷 1048-1050页

作者： XIAO Jianxin 1 and CHEN Shanqing 2 1. china University of Geosciences, Beijing 100083. china 2. Yichang institute of {3. and mineral resources, Yichang 443.03. china china University of Geosciences Beijing China Yichang institute of geology and mineral {3. Yichang China

The humilith series of lignite, longflame coal, gas coal, fat coal, coking coal, lean coal, meagre coal and anthracite are measured by FIR1600 infrared spectrophotometer. The variation curve between the infrared absorption wave number of aromaticring C--C bond of vitrinite and its reflectance values are gained, which shows the shift of infrared absorption wave number of aromaticring C--C bond of humic coals towards lower wave number with the increase of coalification. It is believed that the coal rank of humilith series can be determined and more evolutional information about coal composition and structure can be obtained by the infrared spectroscopic method.

关键词： aromatic_nucleus C--C bond infrared absorption wave number vitrinite humic coal.

Terminal Precambrian Palaeogeographic Framework of china

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Acta Geologica Sinica(English Edition) 1989年第2期63卷 115-125页

作者： Qiao Xiufu, Ma Lifang Geological institute, CAGS, Beijing, and Zhang Huimin Tianjin institute of geology and {3. resources, CAGS, Tianjin Jia Zhongpeng Geological institute CAGS Beijing China

The original locations and relationships of four plates within the mainland of china from 800 to 600 Ma during the terminal Precambrian were reconstructed based on the palaeomagnetic and geological data. The Tarim, Yangtze and Cathaysian plates were once linked (in 800-700 Ma) and located in the same low-latitude zone of the northern hemisphere. But later, in 700-600 Ma, the Tarim plate was separated from the Yangtze-Cathaysian plate. The Sino-Korean plate was always far away from the Yangtze plate, both being separated by oceanic crust, and lay in the high-latitude zone of the northern *** above-mentioned palaeogeographic framework directly led to complete differences in respect to distribution of low-latitude glaciation, sedimentary facies, palaeoclimate, palaeobiogeography and stratigraphic sections between the North and South china domains during the terminal Precambrian.

关键词： Terminal Precambrian Palaeogeographic Framework of china

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 Party, Sichuan Bureau of geology and {3. 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

mineralogy and Mode of Occurrence of Gold, Silver and Bismuth of the Caijiaying Lead-Zine-Silver Deposit, Hebei Province

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Acta Geologica Sinica(English Edition) 1991年第4期65卷 371-385,461页

作者： Huang Dianhao Ding Xiaoshi Wu Chengyu Zhang Changjiang institute of mineral Deposits, Chinese Academy of Geological Sciences, Beijing Geological Party No.3. Hebei Bureau of geology and mineral resources, Zhang jiakou, Hebei Fei Zhenbi institute of mineral Deposits Chinese Academy of Geological Sciences Beijing China

The deposit under study is a hydrothermal filling-metasomatic vein type lead-zinc-silver deposit, in whichgold and silver can be recovered as by-products. These metals mainly occur as microgranular native gold,electrum, stephanite, acanthite, pyraragyrite, freibergite, and native silver. Gold minerals tend to be associatedwith galenobismutite, native bismuth and unnamed Bi_2Te. They are either enclosed in pyrite, marmatite,iron-bearing sphalerite and galens or fill the microfissures of these minerals. Silver minerals usually occur incleavages or fissures of galena, marmatite and pyrite, but are not associated with gold and bismuth minerals.Gold and silver mineralizations occurred later than lead and zinc, while the silver mineralization was precededby that of gold.

关键词： mineralogy and Mode of Occurrence of Gold Hebei Province

Relationships between bacterial-algal proliferating and mass extinction in the Late Devonian Frasnian-Famennian transition:Enlightening from carbon isotopes and molecular fossils

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Science china Earth Sciences 2005年第10期48卷 1656-1665页

作者： GONG Yiming1,2, XU Ran1, TANG Zhongdao1, SI Yuanlan3.& LI Baohua4 1. Faculty of Earth Science and State Key Laboratory of Geological Processes and mineral resources, china University of Geosciences, Wuhan 43.074, china 2. institute of resources & Environments, Henan Polytechnic University, Jiaozuo 454003. china 3. Department of Computer Science, South-Central University for Nationalities, Wuhan 43.074, china 4. Laboratory of Marine geology, Tongji University, Shanghai 200092, china china University of Geosciences Henan Polytechnic University South-Central University for Nationalities Tongji University

Studies show positive shifts of inorganic and organic carbon isotope values (δ 13.carb and δ 13.kerogen) from +0.43.(‰ V-PDB) to +3.54 (‰ V-PDB) and from ?29.3. (‰ V-PDB) to ?24.14 (‰ V-PDB), respectively, B* (Ba* = Ba/ (Al2O3.X 15%)) values from 0.015 to 0.144, TOC values from 0.02% to 0.21%, V/Cr values from 0.3.to 2.0, Sr/Ba values from 3.20 to 49.50 in the Late Devonian Frasnian Upper rhenana zone to the top linguiformis zone of the Yangdi sec-tion deposited in carbonate slope facies of Guilin, Guangxi, South china, which indicates that biomass, productivity, organic carbon burial and salinity increase and that oxygenation near the boundary between sediments and waters decreases from the Late Devonian Frasnian Upper rhenana zone to the top linguiformis zone. Abundance of molecular fossils increases and normal alkanes, isoprenoid hydrocarbon, terpanes and steranes are dominated from the Late Devonian Frasnian to the bottom of Famennian, which shows that the predecessors of molecular fossils of the Frasnian-Famennian (F-F) transition are dominated by marine phytoplankton, zooplankton and benthic bacteria with no photosynthesis. Therefore, it is considered that the F-F transitional mass extinction with a multistage, selection and global synchronizing was caused by bacte-rial-algal proliferating, continuing deterioration of the shallow marine ecoenvironment of the mid-dle-lower latitudes. A simple cause and effect chain can be expressed as: appearance of seed plants and multi-storied forests → enhanced chemical and biochemical weathering and pe-dogenesis → wide development of soils → increasing riverine nutrient fluxes in epicontinental sea → from superoligotrophic to eutrophic in epicontinental sea → proliferating of marine phyto-plankton and zooplankton → frequent red tide and anoxia → mass extinction of shallow marine organisms in the middle-lower latitudes. It is worth notice that the factor drawdown of atmos-pheric Pco2, climatic cooling and sea level falling c

关键词： mass extinction, bacteria-algae, carbon isotopes, molecular fossils, biodiversity, Late Devonian, Guangxi, South china.

Characteristics and origins of primary fluids and noble gases in mantle-derived minerals from the Yishu area,Shandong Province,china

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Science china Earth Sciences 2006年第1期49卷 77-87页

作者： MA Jinlong1,2, TAO Mingxin2,3.& YE Xianren2 1. resources and Environmental School, Lanzhou University, Lanzhou 73.000, china 2. Key Laboratory of Gas Geochemistry, institute of {3. and Geophysics, Chinese Academy of Sciences, Lanzhou 73.000, china 3. College of resources Science & Technology, Beijing Normal University, Beijing 100875, china resources and Environmental School Lanzhou University Lanzhou China Key Laboratory of Gas Geochemistry Institute of Geology and Geophysics Chinese Academy of Sciences Lanzhou China College of resources Science & Technology Beijing Normal University Beijing China

Fluids and noble gases of mantle-derived materials are important tracers forthe mantle information. Compositions of primary fluids and noble gases in mantle-derived mineralsfrom the Yishu area, Shandong Province, china, were tested by the methods of heat-bursting andheat-melting respectively. The fluids are mainly composed of CO_2, CO and H_2, which account forabout 90% of the total, and are similar to the mantle-derived rocks from other areas of easternchina; ratios of ~3.e/~4He in almost all samples range from 0.82 Ra to 2.74 Ra, whereas^(40)Ar/^(3.)Ar from 299.5 to 758.8. Both ranges are much lower than those of the typical oceanmantle-derived samples (such as MORB) and primarily reflect the influences of the atmosphericcomponents and the radiogenic isotopes. Ratios of C/~3.e range from 27.6 x 10~9 to 1050 x 10~9,N_2/Ar from 927 to 56612, and N_2/~3.e from 2.5 x 10~9 to 27 x 10~9, similar to those in westernUnited States and New Zealand which belong to the tectonic plate collision regions. The ratios fallin the intersect of mantle-crust-atmosphere in the comprehensive tracer-charts, reflecting theinfluences of the atmosphere and the crusts with organic components. Our results suggest that thecomposition of the primary fluids and the isotopic ratios of the noble gases may either reflect theevolution process of mantle-derived rocks connected with the rise and eruption of magma, or theinfluence of the ancient subduction-plate on the continental mantle of this region.

关键词： noble gases, primary fluids, mantle-derived minerals, Yishu area.

Zijinshan-Bitian Cu-Au-Mo orefield, SW Fujian——An example of gold-rich PCS zoning

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Chinese Science Bulletin 1999年第S2期44卷 134-135页

作者： QI Jianzhong~1, LI Zhaonai~2, ZHANG Dequan~3. FANG Xiheng~4 and XIAO Huiliang~1 1. Nanjing institute of geology and mineral {3., Chinese Academy of Geological Sciences, Nanjing 210016, china 2. institute of geology, Chinese Academy of Geological Sciences, Beijing 10003., china 3. institute of mineral Deposits, Chinese Academy of Geological Sciences, Beijing 10003., china 4. institute of geology, Ministry of Nuclear Industry, Beijing 100013. china Nanjing institute of geology and mineral {3. Chinese Academy of Geological Sciences Nanjing 210016 China institute of geology Chinese Academy of Geological Sciences Beijing 100037 China institute of mineral Deposits Chinese Academy of Geological Sciences Beijing 100037 China institute of geology Ministry of Nuclear Industry Beijing 100013 China

THE Zijinshan-Bitian Cu-Au-Mo orefield is spread to north of the Shanghang County, SW *** geological structure it is located at the plunging end of NE-trending Xuanhe anticlinorium, in the NE rim ofthe NW trending Shanghang volcano-sedimentary basin. Orefield basement is composed of the Archean-Middle Proterozoic low-grade metamorphic rock formations, containing marine basic metavolcanic sequenses. Lower Cretaceous subaerial volcanic rocks of andesite-trachy andesite-rhyolite composition fill inthe volcano-sedimentary basin. Pre-mineralization granitic batholith dated 145Ma（Rb-Sr）and 157Ma（U-Pb） occupies the axial part of the plunging anticlinorium, which was regarded as crust-remelting typegranitoids. mineralization-affiliated subvolcanic dacite porphyrite, co-volcanic granodiorite and quartzdiorite porphyrite （102.2 Ma（Rb-Sr）, Sr1 = 0.708 9） belong to syntactic type in genesis and

关键词： gold-rich porphyre copper system zoning Fujian Zijinshan.