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

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, {2. University, {2. 2.0093.{3. 2.Guangzhou institute of Geochemistry, Chinese academy of sciences, Guangzhou 510640,{3. 3.Graduate University of Chinese academy of sciences, Beijing 100049,{3. Department of Earth sciences Nanjing University Nanjing 210093 China Guangzhou institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China Graduate University of Chinese academy of sciences Beijing 100049 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

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Carbon isotope composition of the Lower Triassic marine carbonates, Lower Yangtze Region, South china

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science china Earth {2. 2006年第3期49卷 225-241页

作者： ZUO Jingxun1,2. TONG Jinnan3. QIU Haiou4 & ZHAO Laishi3.1. {2. institute of Geology and Palaeontology, Chinese academy of {3., nanjing 2.0008, china 2. Henan institute of Geological Survey, Zhengzhou 450007, china 3. State Key Laboratory of Geological Processes and Mineral Resources at china University of Geo{3., Wuhan 43.074, china 4. Faculty of Material {3. and Chemical Engineering, china University of Geo{3., Wuhan 43.074, china 1. nanjing institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China 2. Henan institute of Geological Survey Zhengzhou 450007 China 3. State Key Laboratory of Geological Processes and Mineral Resources at china University of Geo{2. Wuhan 430074 China 4. Faculty of Material sciences and Chemical Engineering China University of Geosciences Wuhan 430074 China

Studies on three Lower Triassic sections located on the shallow water platform, the deep water slope and in the deep water basin in the Lower Yangtze Region, South china, show the similar trend of carbon isotope evolution. Biostratigraphic correlations among the Lower Triassic sections on the basis of standard conodont zones indicate that three negative shifts occurred in the Griesbachian, the Smithian and the late Spathian stages respectively, and one distinctly positive shift occurred in the early Spathian stage. Trend of carbon isotope evolution of the Lower Triassic reflects some significant changes in the global carbon cycle. Moreover, δ 13. background values are intensively controlled by palaeogeographic environment. In general, δ 13. values from deep-water slope carbonates are lighter than those from carbonate platform and heavier than those from deep-water basin carbonates. The positive carbon isotope excursion may be induced by a significant amount of organic carbon burial in marine sediments and increase in primary productivity. The large negative carbon isotope excursions during the Early Triassic in Lower Yangtze Region are interpreted to relate to volcano eruptions based on tuffaceous claystone interlayers observed near the Permian-Triassic boundary, the Induan- Olenekian boundary and the Lower Triassic-Middle Triassic boundary.

关键词： Lower Triassic, carbon isotope compositions, palaeogeography, volcanic eruptions, Lower Yangtze Region.

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Pedosphere 2003年第1期13卷 11-22页

作者： GONG ZITONG, ZHANG GANLIN, ZHAO WENJUN, ZHAO YUGUO and CHEN ZHICHENGinstitute of soil {2., the Chinese {3. of sciences, nanjing 2.0008 (china) instituteofsoil{2. theChineseAcademyofSciencesNanjing210008China

During the past half century, the land utilization of Hainan Island has undergone a rapid development,but in the meanwhile, soil degradation occurs. Analysis on some basic data of the soil series collected frommore than 100 soil profiles at the end of the 1990s and beginning of this century, in combination with dataavailable, showed that soils there suffered significant decline in organic matter, experienced P and K deficiencywith soil K going on losing and undergone acidification with continuing trend. The current situation calls forstrategies to build up Hainan into an important province of sound ecology by restoring forests, to improvefood quality by implementing K supplement projects, to combat soil acidification by ameliorating the soils andgrowing leguminous crops and to ensure health of the people by developing dairy production and increasingthe daily Ca uptake by the people.

关键词： hainan island land use soil changes

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A study of two-dimensional magnetic polaron

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science china(Physics,Mechanics & Astronomy) 2006年第4期49卷 421-429页

作者： LIU Tao1, ZHANG Huaihong1, FENG Mang1,2.& WANG Kelin1,3.1. School of science, Southwest University of science and Technology, Mianyang 62.010, china 2. Wuhan {3. of Physics and Mathematics, Chinese academy of sciences, Wuhan 43.070, china 3. Department of Modern Physics, University of science and Technology of china, Hefei 2.0}02., china School of science Southwest University of Science Technology Mianyang 621010 China Wuhan institute of Physics Mathematics Chinese Academy of Sciences Wuhan 430070 China Department of Modern Physics University of Science Technology of china Hefei 230026 China

By using the variational method and anneal simulation, we study in this paper the self-trapped magnetic polaron (STMP) in two-dimensional anti-ferromagnetic material and the bound magnetic polaron (BMP) in ferromagnetic material. Schwinger angular momentum theory is applied to changing the problem into a coupling problem of carriers and two types of Bosons. Our calculation shows that there are single-peak and multi-peak structures in the two-dimensional STMP. For the ferromagnetic material, the properties of the two-dimensional BMP are almost the same as that in one-dimensional case; but for the anti-ferromagnetic material, the two-dimensional STMP structure is much richer than the one-dimensional case.

关键词： self-trapped magnetic polaron, bound magnetic polaron, impurity potential, anti-ferromagnet.

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Variation properties of ionospheric eclipse factor and ionospheric influence factor

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Progress in Natural science:Materials International 2005年第6期15卷 573-576页

作者： ZHAO Chunmei 1,2.*, YUAN Yunbin1, OU Jikun1 and CHEN Jinping3.1. institute of Geodesy and Geophysics, Chinese {2. of sciences, Wuhan 43.077,{3. 2. Graduate School of Chinese {2. of sciences, Beijing 10003.,{3. 3. Department of Precision Instrument and Mechanology, Tsinghua University, Beijing 100084,{3.) institute of Geodesy and Geophysics Chinese Academy of Sciences Wuhan 430077 China Graduate School of Chinese academy of sciences Beijing 100039 China Department of Precision Instrument and Mechanology Tsinghua University Beijing 100084 China

The concepts and calculation methods of ionospheric eclipse factor (IEF) and ionospheric influence factor (IFF) are further illustrated. The temporal and spacial variation properties of IEF and IFF are studied, which shows that the properties are influenced by the geographic position and season. The possibility of improving the precision of using GPS data to determine ionospheric delay based on the above variation properties is also analysed.

关键词： GPS ionospheric eclipse factor ionospheric influence factor

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An analysis on the evolvement processes of lake eutrophication and their characteristics of the typical lakes in the middle and lower reaches of Yangtze River

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Chinese science Bulletin 2006年第13期51卷 1603-1613页

作者： CHENG Xiaoying1,2.3.& LI Shijie1 1. nanjing {2. of Geography & Limnology, Chinese academy of {3., nanjing 2.0008, china 2. The Key Laboratory of Industrial Biotechnology, Ministry of Educa- tion, Southern Yangtze University, Wuxi 2.403., china 3. School of Biotechnology, Southern Yangtze University, Wuxi 2.403., china nanjing institute of Geography & Limnology Chinese Academy of Sciences Nanjing China The Key Laboratory of Industrial Biotechnology Ministry of Education Southern Yangtze University Wuxi China School of Biotechnology Southern Yangtze University Wuxi China

According to the study on the aquatic environment of the typical lakes in the middle and lower reaches of Yangtze River, lake eutrophication is a process in which the lake ecosystem degenerates, resulting in the deterioration of the water quality due to the enrichment of the nutrients. Moreover, the succession of lake ecosystem and change of water quality both couple well with the evolvement of tro- phic state. Then the conceptual model is mentioned and ten lake states are classified. Based on these, the authors analyzed the eutrophication processes of the typical lakes in the middle and lower reaches of Yangtze River. The large lakes with taking in - send- ing out water typical of Poyang Lake evolve from State 1 before the 1980s into State 2.after the 1980s, the large and medium lakes typical of Taihu Lake evolve from State 1-2.in the 1960s into State 8 in the 1980s then into State 9 in the 1990s, the medium and small shallow lakes typical of Honghu Lake evolve from State 1 in the 1960s into State 2.after the 1980s and the small city (suburban) lakes typical of Donghu Lake evolve from State 2.in the 1960s into State 9 after the 1970s. Further, the 1980s is the key con- version period of the lakes of various types typical of Poyang Lake, Honghu Lake and Taihu Lake con- verting into mesotrophic state, the 1990s is that of Taihu Lake into eutrophic state and the 1970s is thatof the small city (suburban) lakes typical of Donghu Lake into eutrophic state. The series of nutrient evolvement of different typical lakes are similar, but the processes are not synchronous, which is related to the various human and natural driving mechanisms in lake basins.

关键词：长江湖泊富营养化概念模型转变时期驱动机制

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Experimental and discrete element numerical analysis of side slope instability induced by fissure water underlying impervious bed

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science china(Technological {2.) 2005年第z1期48卷 65-80页

作者： LIU Bingshan1, LI Shihai1, ZHANG Lei1,2.& WANG Jianguo3.. institute of Mechanics, Chinese {2. of sciences, Beijing 100080,{3. 2. Graduate School, Chinese {2. of sciences, Beijing 100060,{3. 3. Tropical Marine science institute, National University of Singapore, 10 Kent Ridge Crescent, Singapore 1192.0 Chinese Acad Sci Inst Mech Beijing 100080 Peoples R China Chinese Acad Sci Grad Sch Beijing 100060 Peoples R China Natl Univ Singapore Trop Marine Sci Inst Singapore 119260 Singapore

When the sliding mass contains impervious bed, rainfall can infiltrate into mountain via crevices and form higher artesian aquifer at impervious bed inferior. This will decrease slip resistance and increase sliding forces of the sliding mass, thus lowering the safety factor, and inducing landslide disasters. In this paper, a landslide experimental apparatus is designed for experimental studies on the mechanism of this type of landslides. Meanwhile, the non-dimensional parameters in the model experiment are taken into account using dimensional analysis. The experimental results show that (1) the ratio of the cleft water pressure to the overlying pressure is a crucial parameter affecting the stability of the slope; (2. when the shut-in pressure reaches 80% of the normal component of the pressure on the slip surface made up of rock and soil, landslide will occur; (3. the whole slope will start to slide when the shut-in pressure is equal to the normal component of the pressure formed by the overlying rock and soil on the upper 3.% area. In this article, a discrete element method simulation is used to investigate the influence of cleft water pressure and shearing strength on the landslide stability. It can be concluded that the critical value of Ccr, ?cr, which determines the slide mass stability, increases with the increase of the water pressure; if the water pressure reaches a high level, the stability of the slide mass depends mainly on C, while the influence of ? becomes smaller than C.

关键词： impervious bed, rainfall infiltration, pore water pressure, landslide experiment, displacement monitor, discrete element method.

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Deposition features of Ni on self-assembled microtubule template from biolipid by electroless method

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science china Chemistry 2004年第3期47卷 228-234页

作者： FU Yubin1,2. ZHANG Lide1, ZHENG Jiyong2. FU Shangang3.& ZHU Mingwei3.1. {2. of Solid State Physics, Chinese academy of sciences, Hefei 2.0}03.,{3. 2. Luoyang Ship Material Research {2., Luoyang 47103.,{3. 3. College of Life {12., Henan Normal University, Xinxiang 453.02.{3. 1. institute of Solid State Physics Chinese Academy of Sciences 230031 Hefei China 2. Luoyang Ship Material Research institute 471039 Luoyang China 3. College of Life science Henan Normal University 453002 Xinxiang China

Diacetylenic glycero-phosphatidylcholine is a chiral molecule with amphiphilic property, and it can self-assembly into a lipid microtubular structure. The lipid microtubule is a stable structure formed by tightly wound helical ribbons, and the ribbon-wrapping patterns have a significant effect on their chemical deposition on the microtubules. The deposition of colloidal Pd catalyst occurs mainly on the helical edge of the wound helical ribbons to form helical deposition lines of colloidal Pd particles in the interior and exterior of the lipid microtubules, resulting in an uneven chemical deposition of Ni on the microtubules. Catalyzed by as-deposited colloidal Pd, metallized Ni microtubules are characterized by a helical form, which may be in relation to inner stress due to the thickness difference or the different deposition processes. The observation of microtom shows that metallized tubules have a hollow structure. Some metallized tubules have a kind of coaxial double layer structure observed in the direct experiment evidence, indicating that metallization can occur in the inner and outer surface of the lipid tubules. Both lipid microtubules and metallized microtubules can be used as vehicles for encapsulating biological active molecules to control their release and to develop micro-components in biological and mechanical systems. Keywords molecular self-assembly - lipid microtubules - helical pattern - site-specific deposition - electroless metallization

关键词： molecular self-assembly, lipid microtubules, helical pattern, site-specific deposition, electroless metallization.

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Grain-size features of a Miocene loess-soil sequence at Qinan: Implications on its origin

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science china Earth {2. 2006年第7期49卷 731-738页

作者： QIAO Yansong1,3. GUO Zhengtang2.1, HAO Qingzhen1, YIN Qiuzhen1, YUAN Baoyin1 & LIU Tungsheng1 1. institute of Geology and Geophysics, Chinese {2. of sciences, Beijing 10002.,{3. 2. institute of Earth Environment, Chinese {2. of sciences, Xi’an 710075,{3. 3. institute of Geomechanics, Chinese {2. of Geological sciences, Beijing 100081,{3. 1. institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China 3. institute of Geomechanics Chinese Academy of Geological Sciences Beijing 100081 China 2. institute of Earth Environment Chinese Academy of Sciences Xi’an 710075 China

In this study, grain-size of 507 bulk samples from the QA-I Mioceneloess-soil sequence at Qinan were analyzed, and the grain-size features are compared with those oftypical Quaternary loess and soil samples, representative lacustrine and fluvial samples. Theresults indicate that the grain-size distribution pattern of the Miocene loess is essentiallysimilar to that of Quaternary loess, but greatly differs from the lacustrine and fluvial *** layers are regularly coarser than soil layers, indicating cyclical climate changes. Mediangrain-size along the 2.3.1 m sequence varies from 6 to 13.μm and the > 63.μm fraction representsonly 5.3. in maximum, 0.9% in average. Long-term grain-size variations are consistent with the loessaccumulation rate at Qinan and with the eolian mass accumulation rate in the North Pacific. Thesefeatures firmly indicate an eolian origin of the studied sequence, and also reveal a coeval changesbetween the long-term changes of eolian grain-size and continental aridity in the dust sourceregions.

关键词： Qinan, Miocene loess-soil sequence, grain-size, eolian origin.

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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 {2. 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,{2. 2. Key Laboratory of Gas Geochemistry, institute of Geology and Geophysics, Chinese academy of {3., Lanzhou 73.000,{2. 3. College of Resources science & Technology, Beijing Normal University, Beijing 100875,{2. 1. Resources and Environmental School Lanzhou University Lanzhou 730000 China 2. Key Laboratory of Gas Geochemistry Institute of Geology and Geophysics Chinese Academy of Sciences Lanzhou 730000 China 3. College of Resources science & Technology Beijing Normal University Beijing 100875 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 ~{2.e/~4He in almost all samples range from 0.82.Ra to 2.74 Ra, whereas^(40)Ar/^({2.)Ar from 2.9.5 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/~{2.e range from 2..6 x 10~9 to 1050 x 10~9,N_2.Ar from 92. to 56612. and N_2.~{2.e from 2.5 x 10~9 to 2. 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.

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