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Ecology of the rehabilitation of vegetation on tropical coastal eroded land in Guangdong， china

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Journal of Environmental sciences 1995年第1期7卷 74-84页

作者： Yu Zuoyue wang Zhuhao South china institute of Botany, chinese academy of sciences,guangzhou 510650,china South china Inst of Botany Chinese Academy of Science Guangzhou China

ＥｃｏｌｏｇｙｏｆｔｈｅｒｅｈａｂｉｌｉｔａｔｉｏｎｏｆｖｅｇｅｔａｔｉｏｎｏｎｔｒｏｐｉｃａｌｃｏａｓｔａｌｅｒｏｄｅｄｌａｎｄｉｎＧｕａｎｇｄｏｎｇ，ＣｈｉｎａＹｕＺｕｏｙｕｅ；ＷａｎｇＺｈｕｈａｏＳｏｕｔｈＣｈ... 详细信息

ＥｃｏｌｏｇｙｏｆｔｈｅｒｅｈａｂｉｌｉｔａｔｉｏｎｏｆｖｅｇｅｔａｔｉｏｎｏｎｔｒｏｐｉｃａｌｃｏａｓｔａｌｅｒｏｄｅｄｌａｎｄｉｎＧｕａｎｇｄｏｎｇ，ＣｈｉｎａＹｕＺｕｏｙｕｅ；ＷａｎｇＺｈｕｈａｏＳｏｕｔｈＣｈｉｎａＩｎｓｔｉｔｕｔｅｏｆＢｏｔ...

关键词： tropics ereded land ecology of vegetation recovery.

NaAlSi_3O_8-hollandite and other high-pressure minerals in the shock melt veins of the Suizhou meteorite

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chinese Science Bulletin 2001年第13期46卷 1121-1126页

作者： XIE Xiande, CHEN Ming, wang Deqiang & El Goresy A.1.guangzhou institute of geochemistry, chinese academy of sciences, guangzhou 510640, china 2. Max-Planck-institute fur Chemie, 55128 Mainz, Germany guangzhou institute of geochemistry Chinese Academy of Sciences Guangzhou 510640 China Max-Planck-institute für Chemie 55128 Mainz Germany

The Suizhou L6 chondrite contains a few very thin shock melt veins of 0.02-0.09 mm in width. In spite of small width of the veins, shock-induced high-pressure phases, such as coarse-grained NaAlSi3O8-hollandite, ringwoodite, majorite and fine-grained matrix majorite-pyropess have been discovered in these veins. NaAlSi3O8-hollandite, the high-pressure phase of plagioclase, in Suizhou shock veins occurs as a single phase mineral, no silicate glassy phase, such as albitic glass, was incorporated with it. The presence of above-mentioned high-pressure phases constrains the high pressure (up to 23-24 GPa) and high temperature (up to 1900-2000℃) regime in Suizhou shock veins, and indicates that the duration of high-pressure regime in the veins should be long enough (a few seconds) for phase transformation and crystallization of minerals under pressure. The discovery of the first natural single-phase crystalline NaAlSi3O8- holland-ite in Suizhou meteorite is of important significance in understanding the Earth’

关键词： high NaAlSi3O8-hollandite and other high-pressure minerals in the shock melt veins of the Suizhou meteorite

TWO TYPES OF CENOZOIC HIGH-K MAGMATINSM IN EASTERN TIBET:IMPLICATIONS FOR THE NATURE OF MANTLE SOURCES

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地学前缘 2000年第S1期7卷 295-296页

作者： wang Jianghai, Xie Guanghong[WT5,5”BX](guangzhou institute of geochemistry, chinese academy of sciences, Wushan, guangzhou 510640, china)

Cenozoic high\|K igneous rocks are widely distributed in eastern Tibet. These rocks are exposed as flows, dykes and small intrusions along a narrow north\|south trending zone, which follows Tertiary fold belts and the Batang—Lijiang and Ailao Shan—Red River strike\|slip systems. Although several models were proposed to interpret their petrogenesis (Deng, 1989; Arnaud et al., 1991; Turner et al., 1996; Yin et al., 1995; Miller et al., 1999), their origin still remains hotly debated. Moreover, the published results were only focused on the high\|K igneous rocks resulted from partial melting of an enriched lithospheric mantle. Here, we present the detailed documents to testify the existence of a new kind of high\|K igneous rocks in eastern *** new 39 Ar/ 40 Ar age data (wang et al., 1999) and published age data for high\|K rocks in eastern Tibet show two distinctive magmatic episodes: one between 42Ma and 24Ma, and the other since ca.16Ma. They correspond to two types of high\|K magmatism in eastern Tibet. We name the older and younger groups as types Ⅰ and Ⅱ, respectively.

关键词： Cenozoic high\|K magmatism enriched and depleted mantle sour ce Pb\|Sr\|Nd isotopes transpressional and transtensional tectonics Eastern T ibet

STUDY ON Ni-Cr SYSTEM SOLAR SELECTIVE THIN FILMS PREPARED BY MAGNETRON REACTIVE SPUTTERING PROCESS

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Acta Metallurgica Sinica(English Letters) 2002年第2期15卷 203-206页

作者： B. W. wang and H. Shen guangzhou institute of Energy Conversion, The chinese academy of sciences, guangzhou 510070, china Inst. of Energy Conversion Chinese Acad. of Sci. Guangzhou 510070 China

Ni-Cr System solar selective thin solid films were prepared by d.c. magnetron reactive sputtering under the atmosphere of O2 and N2. Ni-Cr alloy was chosen as target material and copper sheets as substrate. Using SEAL Spectrophotometer and Talystep to analyze the relations between the selective characteristic and the structure, the formation and the thickness of the thin films. The aim is to obtain good solar selective thin films with high absorptance and low emittance, which is applied to flat plate solar heat collectors.

关键词： solar selective thin film magnetron reactive sputtering. absorptance emittance

Petrology and mineral chemistry of new ureilites found in Grove Mountains, Antarctica

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Progress in Natural Science:Materials International 2008年第4期18卷 431-439页

作者： Bingkui Miaoa,b,, Yangting Linb, Guiqin wangc, daode wangc, Ziyuan Ouyangd a Key Laboratory of Geological Engineering Center of Guangxi Province, Guilin University of Technology, Guilin 541004, china b State Key Laboratory of Lithospheric Evolution, institute of Geology and Geophysics, chinese academy of sciences, Beijing 100029, china c Key Laboratory of Isotope Geochronology and geochemistry, guangzhou institute of geochemistry, chinese academy of sciences, guangzhou 510640, chinad National Astronomical Observatories, chinese academy of sciences, Beijing 100012, china Key Laboratory of Geological Engineering Center of Guangxi Province Guilin University of Technology Guilin 541004 China State Key Laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China Key Laboratory of Isotope Geochronology and geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China

Petrography and mineral chemistry of two new ureilites, GRV 021512 and 022931, from the Grove Mountains, Antarctica, are reported in this paper. GRV 021512 exhibits a typical ureilite texture, and consists of 48.3% olivine, 9.4% pigeonite and 38.1% carbo- naceous interstitial material and/or reduction product. GRV 022931 has a cataclastic porphyritic texture, and consists of 19.1% olivine and 14.1% pigeonite embedded in 66.3% carbonaceous interstitial material and/or reduction product. The coarse-grained olivine and pigeonite in both meteorites have homogeneous cores, and they are FeO-rich within the range of the ferroan subgroup (subgroup I) of olivine-pigeonite ureilites. All olivine grains of the meteorites show reduction zones along boundaries and cracks. Abundant diamond coexists with graphite as graphite-rich patches and veins in the carbonaceous interstitial material. Petrogenesis of both meteorites and the origin of diamond are discussed.

关键词： Meteorite Achondrite Ureilite Diamond Antarctica

The fluxes and controlling factors of N_2O and CH_4 emissions from freshwater marsh in Northeast china

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Science china Earth sciences 2010年第5期53卷 700-709页

作者： YU JunBao1,2, LIU JingShuang2, SUN ZhiGao1, SUN WeiDong3, wang JinDa2, wang GuoPing2 & CHEN XiaoBing1 1 Key Lab of Coastal Envionment Processed, Yantai institute of Coastal Zone Research for Sustainable Development, chinese academy of sciences, Yantai 264003, china 2 Key Lab of Wetland Ecology and Environment, Northeast institute of Geography and Agricultural Ecology, chinese academy of sciences, Changchun 130012, china 3 Key Laboratory of Isotope Geochronology and geochemistry, guangzhou institute of geochemistry, chinese academy of sciences, guangzhou 510640, china Key Lab of Coastal Envionment Processed Yantai Institute of Coastal Zone Research for Sustainable Development Chinese Academy of Sciences Yantai China Key Lab of Wetland Ecology and Environment Northeast Institute of Geography and Agricultural Ecology Chinese Academy of Sciences Changchun China Key Laboratory of Isotope Geochronology and geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China

Nitrous oxide (N2O) and methane (CH4) emissions were measured using a static chamber method in two adjacent plots of freshwater marsh predominated by Calamagrostis angustifolia, one is seasonal waterlogged (SW) and the other without surface water accumulation (NW), in Sanjiang Plain wetland (47°35′N, 133°31′E), northeast china, during 2002-2004. The diurnal and seasonal flux variations of both gases were significantly correlated with 5-cm-soil temperature. The NW marsh is a source of N2O and sink of CH4, while the SW marsh is sink of N2O and source of CH4. Remarkably, we observed a N2O emission peak under Eh of +300 to +100 mV, and CH4 emission peak under Eh of +300 to +400 mV, which indicate additional sources of N2O and CH4 for the freeze-thaw induced emission peaks of N2O and CH4 observed between late July and early August. Further study shows that the additional N2O and CH4 were emitted under the frozen soil after thawing.

关键词： freeze-thaw region freshwater marsh methane nitrous oxide controlling factors

Modern microbialites and their environmental signifi-cance,Meiji reef atoll,Nansha (Spratly) Islands,South china Sea

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Science china Earth sciences 2008年第4期51卷 608-617页

作者： SHEN JianWei1 & wang Yue1,2 1 Department of Marine Geology, South china Sea institute of Oceanology Key Laboratory of Marginal Sea Geology, South china Sea institute of Oceanology and guangzhou institute of geochemistry, chinese academy of sciences, guangzhou 510301, china 2 Graduate University of the chinese academy of sciences, Beijing 100049, china Department of Marine Geology South China Sea Institute of Oceanology Guangzhou China Key Laboratory of Marginal Sea Geology South China Sea Institute of Oceanology and Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China Graduate University of the chinese academy of sciences Beijing China

Meiji (Mischief) coral atoll, in Nansha (Spratly) Islands, South china Sea, consists of an annular reef rim surrounding a central lagoon. On the atoll rim there are either protuberant 'motu' (small coral patch reefs on the rim of atoll) islets or lower sandy cays that contain modern microbialite deposits on the corals in pinnacles and surrounding bottoms of the atoll. Microbialites, including villiform, hairy, and thin spine growth forms, as well as gelatinous masses, mats and encrustation, developed on coral colonies and atoll rim sediments between 0 and 15 m deep-water settings. The microbialites were produced by natural populations of filamentous cyanobacteria and grew on (1) bulbous corals together with Acropora sp., (2) on massive colonies of Galaxea fascicularis, (3) on dead Montipora digitata, and (4) on dead Acropora teres, some hairy microbialite growing around broken coral branches. This study demonstrates that microbial carbonates are developed in coral reefs of South china Sea and indicates that microbial processes may be important in the construction of modern reef systems. The results have significance in the determination of nature and composition in microorganisms implied in the formation ancient microbialites, and permit evaluation of the importance of microbial deposits in mo-dern coral reefs and of 'microbialites' in biogeochemical cycles of modern coral reef systems. The re-sults also provide evidence of modern analogues for ancient microbialites in shallow-water settings, and combine with sedimentological studies of ancient microbialites to understand their controls.

关键词： Microbialite Meiji reef Nansha Island South china Sea

Total alkyl dibenzothiophenes content tracing the filling pathway of condensate reservoir in the Fushan Depression,South china Sea

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Science china Earth sciences 2008年第S2期51卷 138-145页

作者： LI MeiJun1,wang TieGuan1,LIU Ju2,ZHANG MeiZhu2,LU Hong3,MA QinLin2 & GAO LiHui2 1 State Key Laboratory of Petroleum Resources and Prospecting,Earth sciences and Geoinformatics School,china University of Petroleum,Beijing 102249,china 2 Southern Oil Exploration and Development Company,Petrochina,guangzhou 510640,china 3 guangzhou institute of geochemistry,chinese academy of sciences,guangzhou 510240,china State Key Laboratory of Petroleum Resources and Prospecting Earth Sciences and Geoinformatics School China University of Petroleum Beijing China Southern Oil Exploration and Development Company PetroChina Guangzhou China guangzhou institute of geochemistry Chinese Academy of Sciences Guangzhou China

The condensates are generally characterized by high maturity,low concentration of steranes and ter-panes biomarkers and low content of non-hydrocarbon fraction. In this case commonly used steranes,terpanes and carbazoles parameters cannot be effectively applied in the reservoir-filling tracing. The hydrogen bond formed by sulfur atom in the dibenzothiophenes (DBTs) results in molecule adsorption and fractionation during oil migration in reservoir. Like carbazoles,total DBTs content decreases with the increasing of oil migration distance. Therefore,a new parameter——total DBTs content is proposed to be used to trace the oil migration orientation and filling pathway. In present study,total DBTs con-tents of condensates and light oils are obtained by adding internal standard——eight deuterium atoms substituted DBT during Gas Chromatography-Mass Spectrometry analysis of aromatic fraction. Except for a few samples with much lower content of non-hydrocarbon fraction,the total DBTs content shows a fine positive correlation with that of carbazoles. Large errors can be caused in the process of pyrrolic nitrogen compounds separation. The application of this new parameter in the Fushan Depression of Beibu Gulf Basin,South china Sea indicates that this parameter is a reliable one to trace filling pathway in condensate reservoirs. Combined with other DBTs-related parameters,such as 4-/1-methydibenzo-thiophene and 2,4-/1,4-dimethyldibenzothiophene,oil migration orientation and filling pathway of the Fushan Depression was determined. The accumulations of Huachang oil field in the Fushan Depres-sion are mainly migrated and charged from northeast to southeast along the Huachang uplift. It can be predicated that the light oil and condensates in the Huachang oil field should be sourced from the source kitchen at the Bailian Sag. It shows that total DBTs content is an effective parameter to tracing oil migration orientation and filling pathway.

关键词： dibenzothiophene alkyl dibenzothiophene condensate reservoir filling pathway molecular markers the Fushan Depression

^(40)Ar-^(39)Ar ages of the Louzidian-Dachengzi ductile shear zone near Chifeng,Inner Mongolia and their tectonic significance

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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, china 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 geochemistry 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 126 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.