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^(14.C measurement of forest soils in Dinghushan Biosphere Reserve

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chinese Science Bulletin 1999年第3期44卷 251-256页

作者： SHEN Chengde , LIU Dongsheng (LIU Tungsheng) , PENG Shaolin, SUN Yanmin , JIANG Mantao , Yl Weixi , XING Changping , GAO Quanzhou , LI Zhi’an and ZHOU Guoyi guangzhou institute of Geochemisry, chinese academy of sciences, guangzhou 51064., China institute of Geology, chinese academy of sciences , Beijing 100029, China South China institute of Botany, chinese academy of sciences, guangzhou 510650, China Guannzhou institute of Geochemisry Chinese Academy of Sciences Guanazhou China institute of Geology Chinese Academy of Sciences Beijing China South China institute of Botany Chinese Academy of Sciences Guangzhou China

Organic carbon in forest soils of Qingyunsi and Wukesong profiles can be divided into fast and slow components. Δ14. values of these profiles decrease with increasing of depth. The Δ14. values in 30—4. cm depth int... 详细信息

Organic carbon in forest soils of Qingyunsi and Wukesong profiles can be divided into fast and slow components. Δ14./sup>C values of these profiles decrease with increasing of depth. The Δ14./sup>C values in 30—4. cm depth interval of Wukesong profile are decreasing sharply until a very low value,showing that a strong geological environment change occurred about 1 560 years ago. The 14./sup>C apparent ages of Wukesong profile show that the coniferous and broad-leaf mixed forests around Wukesong profile have been developing since 4.5 a BP, which is consistent with historical documents. The penetrating depths of "bomb 14./sup>C" in Qingyunsi and Wukesong profiles are 10 and 20 cm, respectively.

关键词： Dinghushan forest soil 14. tracing 14. apparent age.

Neutron capture effects and pre-atmospheric sizes of meteoroids

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chinese Science Bulletin 2003年第20期48卷 2236-2240页

作者： WANG Daode & LIN Yangting guangzhou institute of geochemistry, chinese academy of sciences,{4., China Correspondence should be addressed to Wang Daode (e-mail: gzwangdd @***) guangzhou institute of geochemistry Chinese Academy of Sciences Guangzhou 510640 China

Excesses of 80Kr and 82Kr, produced by secondary neutron capture effects of 79Br and 81Br, were observed in meteorites. Epithermal neutron flux, Jn (30—300 eV), and fast neutron flux, Jn( > 5 MeV), were determined according to reactions of 79Br(n, gb)80Kr, 81Br(n, gb)82Kr, and 24.g(n, a)21Ne, respectively. Cosmogenic noble gases of several ordinary chondrites fell in China indicate a positive relationship between Jn (30—300 eV)/Jn ( > 5 MeV) ratio and Jn (30—300 eV). This suggests large pre-atmospheric sizes of the meteorites, and a considerable fraction of the secondary neutrons were slowed down to epithermal energy. According to its relationship with Jn (30—300 eV)/Jn ( > 5 MeV) ratio, the pre-atmospheric minimum radii and masses of several chinese chondrites were estimated as below: Zhaodong: 60 cm, 3200 kg; Laochengzhen: 23 cm, 4.0 kg; Suizhou: 31 cm, 4.0 kg; Xi Ujimgin: 22 cm, 160 kg; Dongtai: 21 cm, 14. kg.

关键词：流星体陨星中子俘获大气层前尺寸宇宙成因核素

Association between Alcohol, Smoking and HLA-DQA1*0201 Genotype in Psoriasis

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Acta Biochimica et Biophysica Sinica 2004年第9期36卷 597-602页

作者： Guang-Yong ZHENG1,2#, Sheng-Cai WEI3#, Tie-Liu SHI1, and Yi-Xue LI1* 1Bioinformatics Center, Shanghai institutes for Biological sciences, chinese academy of sciences, Graduate School of the chinese academy of sciences, Shanghai 200031, China Research Center for Proteome Analysis, institute of Biochemistry and Cell Biology, Shanghai institutes for Biological sciences, chinese academy of sciences, Graduate School of the chinese academy of sciences, Shanghai 200031, China 3guangzhou institute of Dermatology, guangzhou 510095, China Bioinformatics Center Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Graduate School of the Chinese Academy of SciencesShanghai 200031 China Research Center for Proteome Analysis Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Graduate School of the Chinese Academy of SciencesShanghai 200031 China guangzhou institute of Dermatologyguangzhou 510095 China

Psoriasis is a chronic skin disease triggered by genetic, environment or other risk factors such as infection, drugs, stress, moisture, alcohol, and smoking. A major psoriasis susceptibility locus at 6p21.3 has been identified. Further studies found that HLA-DQA1*0201 allele was associated with psoriasis. However, there were few data exploring an association between the environmental factors and susceptibility genes. In this study, the samples of 189 patients with psoriasis and 333 healthy controls were collected with their consent and were carried on analysis through polymerase chain reaction sequence-specific primer (PCR- SSP) method. The proportion of male psoriasis patients engaging in the smoking and alcohol was much higher than that of the control group (P4.25, P6.91, P4..

关键词： psoriasis HLA-DQA1*0201 allele smoking alcohol association

Experimental Study of Partial Melting of Mantle Peridotite -A Discussion about the Genesis of Sih'ca-rich Fluids (Melts)

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Acta Geologica Sinica(English Edition) 1999年第4期73卷 395-403页

作者： LI Jianping guangzhou institute of geochemistry, chinese academy of sciences, guangzhou, 51064., Chinaand Kornprobst JACQUES Departement des sciences de la Terre, Universite Blaise Pascal, 610038 Clermont-Ferrand, France chinese Acad Sci Guangzhou Inst Geochem Guangzhou 510640 Peoples R China Univ Blaise Pascal Dept Sci Terre F-610038 Clermont Ferrand France

Experiments on partial melting of mantle lherzolite have been realized at 0.6 and 1.0 GPa and the chemical compositional variations of melts during different melting stages have been first discussed. The results show that the trends of variations in SiO2, CaO, Al2O3, Na2O and TiO2 are different at different melting stages. The melts produced at lower pressure are richer in SiO2 than those at higher pressure. The mantle-derived silica-rich fluids (silicate melts) are polygenetic, but the basic and intermediate-acid silicate melts in mantle peridotite xenoliths from the same host rocks, which have equivalent contents of volatile and alkali components and different contents of other components, should result from in-situ (low-degree) partial melting of mantle peridotite under different conditions (e.g. at different depths, with introduction of C-O-H fluids or in the presence of metasomatic minerals). The intermediate-acid melts may be the result of partial melting (at lower pressure) Opx + Sp + K-Na-rich fluid ±(Am-phi) ± (Phlog) = OI + melt. But the intermediate-acid magmas cannot be produced from the partial melting of normal mantle peridotite unless the crustal materials are introduced to some extent.

关键词： mantle peridotite in-situ partial melting compositional variation of melt genesis of silica-rich fluid (stlicate melt)

Low-temperature mineralization domain associated with the parallel positions between geochemical steep zones and geophysical gradient zones

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chinese Science Bulletin 1999年第S2期44卷 166-168页

作者： ZHU Bingquan, DONG Yunpeng, CHANG Xiangyang and ZHANG Zhengwei guangzhou institute of geochemistry, chinese academy of sciences,{4., China guangzhou institute of geochemistry Chinese Academy of Sciences Guangzhou 510640 China

THE parallel strike of geochemical steep zones and geophysical gradient zones represent geochemicalboundaries with tectonic hiding and almost no magmatism, but there existed great variation of lithosphereor crustal thickness. Tectonically, these areas were located in the foreland basins of craton margin. Thesegeochemical boundaries were usually associated with the low-temperature mineralization and petroleumgeneration. The Nd, Sr and Pb isotopic evidence indicated that there still existed strong crustal-mantle interaction through fluid activation along deep-seated faults at the craton margin. Fig. 1 is the 207Pb/204./sup> Pb-208Pb/204./sup> Pb diagram, which shows the evident crust-mantle mixing for crude oil, chloroform bitumen-A,

关键词： low temperature mineralization domain geochemical steep zones geophysical gradient zones.

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 {4., chinese academy of sciences, guangzhou 510301, China 2 Graduate University of the chinese academy of sciences, Beijing 10004., 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

Kinetics of early methane generation from Green River shale

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chinese Science Bulletin 1998年第22期43卷 1908-1912页

作者： LIU Jinzhong\+1 and TANG Yongchun 2 1. Laboratory of Organic geochemistry, guangzhou institute of geochemistry,{4., guangzhou 51064., China 2. Chevron Petroleum Technology Company, CA 90633, USA Laborarory of Organic geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China Chevron Petroleum Technology Company USA

During oil/gas exploration in an area, there is a question as to whether methane in the strata was generated \%in situ\% mainly by thermal degradation of local organic matter. The key to the question is whether the kerogen could produce methane of more than 80 mL/g TOC, when its \%R\%\-o increased from initial (0.36%) to current value of 0.70% during thermal evolution. The authors have made efforts to answer this question by the kinetics method. First, a series of pyrolysis experiments were carried out to obtain data of methane yield and \%R\%\-o evolution, from which kinetic parameters of methane and \%R\%\-o were derived; then these parameters were extrapolated to the geological condition and finally, a methane yield, 96 mL/g TOC, was predicted. The result suggests that from the view of hydrocarbon generation, methane in the seam should be from thermal degradation of local kerogen.

关键词： methane kinetics pyrolysis organic geochemistry.

Lincang Superlarge Germanium Deposit in Yunnan Province,China: Sedimentation,Diagenesis,Hydrothermal Process and Mineralization

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Journal of Earth Science 1998年第2期17卷 37-44页

作者： Zhuang Hanping Lu Jialan Fu Jiamo Liu Jinzhong guangzhou institute of geochemistry, chinese academy of sciences,{4.

The mineralization is related closely to sedimentation, diagenesis and hydrothermal processes. In this paper, investigations are carried out on coal occurrence, maceral composition, inorganic minerals, trace elements and huminite reflectance. It is concluded that the source of Lincang superlarge deposit is mainly the muscovite granite in the west edge of the basin. During sedimentation, Ge (germanium) was leached out and entered the basin. Ge was adsorbed by lower organism and humic substances in water. Lincang lignite underwent three thermal processes: peatification, early diagenesis and hydrothermal transformation. During peatification, Ge was adsorbed or complexed by humic colloids. During early diagenesis, the Ge associated with humic acids was hard to mobilize or transport. Most of Ge entered the structure of huminite while a small amount of Ge was associated with residual humic acids as complex or humate. During hydrothermal transformation, the heated natural water or deep fluid from basement encountered the coal layer within tectonic weak zone. SO 2- 4. was reduced by coal organic matter. Pyrite and calcite formed. Hydrothermal process did not contribute significantly to mineralization.

关键词： Lincang superlarge germanium deposit sedimentation diagenesis hydrothermal process mineralization.

Eclogites in the interior of the Tibetan Plateau and their geodynamic implications

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chinese Science Bulletin 2009年第15期54卷 2556-2567页

作者： ZHANG KaiJun1,2 & TANG XianChun2,3 1 Department of Earth sciences, Nanjing University, Nanjing 210093, China 2 guangzhou institute of geochemistry,{4., guangzhou 51064., China 3 Graduate University of{4., Beijing 10004., China Department of Earth sciences Nanjing University Nanjing China guangzhou institute of geochemistry Chinese Academy of Sciences Guangzhou China Graduate University of chinese academy of sciences Beijing China

Eclogites have been recently reported in the interior of the Tibetan Plateau, including in the central Qiangtang metamorphic belt, in the Basu metamorphic massif of the eastern Bangong-Nujiang suture zone, and at Songdo and Pengco in the eastern Lhasa terrane. Some typical ultrahigh-pressure (UHP) metamorphic phenomena, e.g., garnet exsolution from clinopyroxene, were documented in the Basu and Pengco eclogites. The UHP metamorphism in the interior of the Tibetan Plateau marked by these eclogites generally took place in the Early Mesozoic. Along with exhumation of these eclogites, (post-) collision-related magmatism extensively occurred around the central Qiangtang belt, the eastern Ban-gong-Nujiang suture zone, and the eastern Lhasa terrane. The occurrence of these Early Mesozoic ec-logites manifests an out-of-sequence evolution of the Tethys, and they could be a product of diachro-nous collision between the eastern Qiangtang terrane and the irregular continental margin of the united western Qiangtang-Lhasa plate, along the linked eastern Bangong-Nujiang-central Qiangtang zone. The collision-related magmatic rocks could have been originated from lithospheric thickening, melting, or detachment due to the collision. The presence of UHP metamorphic rocks in central Qiangtang and Basu implies likely continental deep-subduction, and the denudation of these two metamorphic zones could have served as the source of the Triassic turbidites in the Songpan-Garzê complex and the Ju-rassic turbidites in the western Bangong-Nujiang zone, respectively. However, studies of the eclogites in the interior of the Tibetan Plateau just began, and many principal aspects still remain to be explored, such as their distributions, typical lithologies and minerals, temperature-pressure conditions, timing of formation and exhumation, protoliths and tectonic setting, and relationship with the evolution of the Tethys and large-scale basins in Tibet.

关键词：地球动力学意义青藏高原榴辉岩