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chinese Science Bulletin 2002年第15期47卷 1292-1297页

作者： ZHANG Xiaohui, LI Tiesheng, PU Zhiping & WANG HuiResearch Center for Mineral Resources Exploration, institute of Geology and Geophysics, chinese academy of sciences, Beijing 100101,{2. guangzhou institute of geochemistry, chinese academy of sciences, G Research Center for Mineral Resources Exploration Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China guangzhou institute of {2. Chinese Academy of Sciences Guangzhou China

The Louzidian normal fault occurs as the eastern detachment fault of the Kalaqin metamorphic core complex. Field observations and microstructural analyses reveal that the Louzidian-Dachengzi ductile shear zone developed in its lower-plate was genetically related to sinistral strike-slips and extensional faulting. Two samples from this ductile shear zone yield 40Ar-39Ar plateau ages of 133 Ma (Bi) and 12. Ma (Kp), which are concordant with their isochron ages. The plateau age of 133 Ma (Bi) records the formation age of the ductile shear zone. The inconsistent relationship between the earlier strike-slip ductile shear zone and the later normal fault makes the Kalaqin Quasi-metamorphic core complex distinctive from Cordil-leran nietamorphic core complex. These ages provide important geochronological data for putting constraints on the formation age and genesis of such ductile shear zones.

关键词： 40Ar-39Ar age Sinistral strike-slip Louzidian-Dachengzi ductile shear zone Metamorphic core complex.

Chronological and geochemical studies of granite and enclave in Baimashan pluton, Hunan, South china

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Science china Earth sciences 2007年第11期50卷 1606-1627页

作者： CHEN WeiFeng1, CHEN PeiRong1, HUANG HongYe2. DING Xing1,3 & SUN Tao1 1 State Key Laboratory of Mineral Deposit Research, Department of Earth sciences, Nanjing University, Nanjing 2.0093, china 2.Research {2. No.2.0, CNNC, Changsha 410011, china 3 guangzhou {2. of geochemistry, chinese academy of sciences, guangzhou 510640, china State Key Laboratory of Mineral Deposit Research Department of Earth Sciences Nanjing University Nanjing China Research institute No.2.0 CNNC Changsha China guangzhou institute of {2. Chinese Academy of Sciences Guangzhou China

Zircon LA-ICP-MS U-Pb dating reveals that the Baimashan Pluton is composed mainly of late Indosinian (2.4.5±2.8 Ma-2.9.2.3.8 Ma) biotite granodiorites/monzonitic granites (LIGs) and early Yanshanian (176.7±1.7 Ma) two-micas monzonitic granites (EYGs), and the coeval (2.3.2.4.5 Ma-2.5.1±3.9 Ma) mafic microgranular enclaves (MMEs) are generally found in the former. In addition, the ages of cores within zircons from LIGs and MMEs ranging from 2.1.4±4.0 Ma to 2.6.5±4.1Ma provide evidence of multistage magma intrusion during Indosinian in the study area. Measured 3010±2..6 Ma of inherited zircon age suggests that there may be recycling Archaean curstal material in existence in this area. LIGs and EYGs share some similar geochemical features: subalkaline and peraluminous granites, enrichment of Th, U, K, Ta, Zr, Hf and LREE but depletion of Ba, Nb, P, Ti and Eu, low εNd(t) values but high (87Sr/86Sr)i ratios, and old T2.M (ca. 1.9-2.0 Ga). The behaviors of incompatible elements and REE are mainly dominated by fractional crystallization of plagioclase, K-feldspar, ilmenite and apatite, but that of Sr isotope mainly controlled by EC-AFC. They are crust-sourced and derived from partial melting of paleo-Proterozoic metagreywackes and related to biotite dehydration melting. LIGs are formed in post-collisional tectonic setting as crustal local extension and thinning during late Indosinian. But EYGs may be evolved products of congeneric granitic magma with LIGs formed in late Indoinian, which were emplaced again when crust underwent extensive thinning and extension in post-orogenic tectonic setting during Yanshanian in SC after undergoing EC-AFC. MMEs should be cognate enclaves and derived from liquid immiscibility of host magma.

关键词： granite,mafic microgranular enclave,zircon LA-ICP-MS dating,lithogenesis,EC-AFC

geochemistry of high-Mg andesites from the early Cretaceous Yixian Formation, western Liaoning: Implications for lower crustal delamination and Sr/Y variations

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Science china Earth sciences 2006年第9期49卷 904-914页

作者： WANG Xiaorui1, GAO Shan1,2. LIU Xiaoming1, YUAN Honglin1, HU Zhaochu1, ZHANG Hong1,3 & WANG Xuance4 1. State Key Laboratory of Continental Dynamics, Department of Geology, Northwest University, Xi`an 710069, china 2. State Key Laboratory of Geological Processes and Mineral Resources, china University of Geo{2., Wuhan 430074, china 3. Shenyang institute of Geology and Mineral Resources, Shenyang 110032. china 4. guangzhou institute of geochemistry, chinese academy of sciences, guangzhou 510640, china State Key Laboratory of Continental Dynamics Department of Geology Northwest University Xi’an China State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Wuhan China Shenyang institute of Geology and Mineral Resources Shenyang China guangzhou institute of {2. Chinese Academy of Sciences Guangzhou China

85 volcanic rocks of the Yixian Formation from the Sihetun type section werecollected and analyzed for geochemical and isotopic compositions. Major element compositionsindicate that the Sihetun volcanic rocks are high magnesium andesites with some basalts occurring atthe bottom of section. The Sihetun high magnesium andesites (SiO_2.= 52.82.59.31 wt%, Al_2._3=14.15-16.35wt%) show many characteristics of adakites such as depletion in heavy rare-earth elements(HREE; Yb = 1.03-1.88 μg/g) and Y(12.2. μg/g) and high Sr (62.-132. μg/g) and Sr/Y(32.88), withhigh La_N/Yb_N ratio (10-2.). They share similar major and trace element characteristics to volcanicrocks from the Xinglonggou Formation except their lower Nd isotope ratios (^(143)Nd/^(144)Nd(130Ma) = 0.5118-0.5119, ε_(Nd) (130Ma) = -11.6-13.8, ^(87)Sr/^(86)Sr (130 Ma) = *** were interpreted in a way that eclogite that formed at the base of thickened Archean lowercrust of the North china craton foundered into the convecting mantle and subsequently melted andinteracted with peridotite. However, compared to the Xinglonggou volcanic rocks, the source of theSihetun magma contained more ancient continental crustal material in order to explain its evolved Ndisotopes. The age of the Sihetun Formation was 12. to 130 Ma, and this indicates that delaminationlasted to the early Cretaceous period. The Sr contents and Sr/Y ratios of the Sihetun high-Mgandesites show significant negative correlations with SiO_2.for samples with SiO_2.> 56%. Thesesuggest that the Sr and Sr/Y values were reduced due to fractional crystallization of ***, the effect of crystallization on volcanic Sr and Sr/Y ratio has to be taken intoaccount.

关键词： High-Mg andesite, Adakite, Yixian Formation, North china Craton, delamination.

Quasirational dynamic system

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chinese Science Bulletin 2000年第14期45卷 1277-1279页

作者： SUN Daochun & YANG Lo1. Department of Mathematics, South china Normal University, guangzhou 510631, china 2. institute of Mathematics, academy of Mathematics and System sciences, chinese academy of sciences, Beijing 100080, china Department of Mathematics South China Normal University Guangzhou China institute of Mathematics Academy of Mathematics and System Sciences Chinese Academy of Sciences Beijing China

Using the iterations of quasirational mappings, the theorems on dynamic system are generalized to the quasirational dynamic system. Some different results are also obtained.

关键词： quasirational mapping dynamic system covering surface.

Mineralization of sediment-hosted ore deposits in reef-chert suite in china

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chinese Science Bulletin 1999年第S2期44卷 271-272页

作者： CHEN Duofu, CHEN Xiangpei, GAO Jiyuan, PAN Jingming and CHEN Guangqian Guangzbou institute of geochemistry,{2., guangzhou 510640, china guangzhou institute of {2. Chinese Academy of Sciences Guangzhou 510640 China

THE reef-chert suite, named by Chen, mainly consists of four types of rocks, with reef carbonate in thelower part, fine detrital rocks in the upper part, chert beds with ore bodies in the intermediate, and synchronous volcanic rocks either in this sequence or in the same sequence in the neighboring district. It isformed as a fixed and ordered suite in space and time, and is the comprehensive product of normal sedimentary process, biological process in extensional basin, hydrothermal sedimentary process near basinbase and magmatic process in the deep of lithosphere in the special geological setting. Many of thesediment-hosted ore deposits usually occur in such a suite in china, such as Dajiangping pyrite deposit,Shuikoushan lead-zinc ore deposit, Changkeng gold-silver deposit, Dachang cassiterite-lead-zinc ore deposit, Xikuangshan stibium ore deposit, Changba-Lijiangou lead-zinc ore deposit, Baiyunebo

关键词： sediment-hosted deposits reef-chert suite china.

Study on fish community structure in the Zhujiang Estuaryand its adjacent waters

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Acta Oceanologica Sinica 1999年第4期18卷 581-589页

作者： Zhan Haigang( South china As Fisheries institute, {2. academy of Fishery sciences, guangzhou 510300, china) South china Sea Fisheries institute Chinese Academy of Fishery Sciences Guangzhou 510300 China

Based on data of demersal trawl Samples from 1987 to 1988 in the Zhujiang Estuary and its adjacent waters, relationships between fish community and environmental factors are studied by using clssification , MDS ordina-tion and several community parameters. The results shaw that the distribution of fish shoes is zoned by salinty anddivided into three types. The freshwater community which is restricted in the Lianhua Hill - Humen waterway is sim-ple and stable, the coastal community which lives in the shallow waters is complex, and the estuary community whichis idenhfied in the Lingdingyang area and affected by Physical and ecological pinemore greatly greatly has obvious seasonalvariations.

关键词： Zhujiang Estuary fish community structure ordination

Identification of marine natural gases with different origin sources

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Science china Earth sciences 2008年第S1期51卷 148-164页

作者： WANG YunPeng 1 ,ZHAO ChangYi 2.,WANG ZhaoYun 2.,WANG HongJun 2.,TIAN Jin 1 ,ZOU YanRong 1 &LIU JinZhong1 1State Key Laboratory of Organic geochemistry,guangzhou {2. of geochemistry,chinese academy of sciences,guangzhou 510640,china 2.2. of Geology,Research {2. of Petroleum Exploration and Development,Petrochina,Beijing 100083,china institute of Geology Research Institute of Petroleum Exploration and Development

Kinetic experiments of gas generation for typical samples of marine gas precursors including low-maturity kerogen,residual kerogen and oil as well as dispersed liquid hydrocarbon(DLH)in source rocks were performed by closed system,and the evolution trends of molecular and isotopic compositions of natural gases from different precursors against the maturity(R0%)at laboratory conditions were *** diagrams of gas origin were calibrated by using the experimental data.A diagram based on the ratio of normal and isomerous butane and pentane(i/nC4-i/nC5)was proposed and used to identify the origins of the typical marine natural gases in the Sichuan Basin and the Tarim Basin, *** the maturities of natural gases were estimated by using the statistical relationships between the gaseous molecular carbon isotopic data and maturities(δ13C-R 0 %)with different *** results indicate that the molecular and isotopic compositions of simulated gases from different precursors are different from each *** example,the dryness index of the oil-cracking gas is the lowest;the dryness indices of gases from DLH and kerogen in closed system are almost the same;and the dryness index of gases from residual kerogen is extremely high,indicating that the kerogen gases are very dry;the contents of non-hydrocarbon gases in kerogen-cracking gases are far higher than those in oil-cracking and DLH-cracking *** molecular carbon isotopes of oil-cracking gases are the lightest,those of kerogen in closed system and GLH-cracking gases are the second lightest,and those of cracking gases from residual kerogen are the *** calibration results indicate that the diagrams of ln(C1/C2.-ln(C2.C3)andδ13C2.δ13C3-ln(C2.C3)can discriminate primary and secondary cracking gases,but cannot be used to identify gas origin sources,while the diagram of i/nC4-i/nC5 can differentiate the gases from different *** application results of these diagrams show that gas mixtures ext

关键词： marine organic matter gas origin sources kerogen oil-cracking gas origin identification carbon isotope

The non-point source (NFS) information system based on remote sensing and GIS and its preliminary application

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chinese Science Bulletin 2000年第S1期45卷 71-75,116页

作者： WANG Yunpengguangzhou institute of {2., chinese academy of sciences, guangzhou 510640, china

A non-point source information system (NPSIS) has been constructed by use of remote sensing and GIS technology, and a construction method of NPSIS introduced with Shenzhen as an example. With the remote sensing land-using images as an environment unit, the analysis modules based on NPSIS are built through combining the NPS model with NPSIS, and the preliminary NPS calculation and analysis performed.

关键词： remote sensing GIS non-point source NPS information system.

Fractal Features and Computer Simulation of Fan-Shaped Sedimentary Bodies in Faulted Basins

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Journal of Earth Science 1998年第3期17卷 50-51页

作者： Zhou Jiangyu guangzhou institute of {2., chinese academy of sciences, guangzhou 510640 Wu Chonglong Faculty of Earth Resources, china University of Geosciences, Wuhan 430074

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关键词： fan shaped sedimentary body nonlinear dynamics fractal fractal dimension kriging numerical simulation fault basin.

Wave Loads and Protective Techniques of An On-Shore Wave Power Device

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china Ocean Engineering 1995年第4期10卷 455-464页

作者： You YageYuZhi Associated Professor, guangzhou institute of Energy Conversion,{2.,guangzhou 510070. Professor, guangzhou institute of Energy Conversion,{2., guangzhou 510070

In this paper, the extreme wave loads on an on-shore wave power device are investigated. First, boundary element method is applied to solve the three dimensional potential problem based on the small amplitude wave assumption. Then the motion of the Oscillating Water Column (OWC) inside the device and its laods on the device are calculated in time domain. Several protective techniques often applied are simulated by changing the constraint of the upper end of the chamber of the device. Numerical results are used to judge the effectiveness of these techniques. The investigation shows that damping can not effectively restrain the motion of OWC when the period of incident wave is long, which may cause dangerous loads on the structure. The shut chamber can effectively restrain the motion of OWC, but alternatively cause high pressure in the chamber. A Contracting opening with a Taper (CT) can exhaust a great amount of kinetic energy of OWC, and significantly decrease the loads. It is a promising protective technique.

关键词： wave powr device protective technique wave load