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Ostracod fauna across the Permian-Triassic boundary at Chongyang, Hubei Province, and its implication for the process of the mass extinction

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Science china earth sciences 2010年第6期53卷 810-817页

作者： LIU Hao1, WANG YongBiao1, YUAN AiHua2, YANG Hao1, SONG HaiJun1 & ZHANG SuXin21 key laboratory of Biogeology and Environmental Geology of Ministry of Education, wuhan 43.074, china 2 state key laboratory of geological processes and mineral resources, wuhan 43.074, china key laboratory of Biogeology and Environmental Geology of Ministry of Education Wuhan China state key laboratory of geological processes and mineral resources Wuhan China

Thirty species of 10 ostracod genera were identified from 440 fossil specimens isolated through the hot acetolysis of the rock samples collected across the Permian-Triassic boundary at Chongyang section. Twenty species of 6 genera are found to occur in the limestone of Changxing Formation, and 11 species of 7 genera above the main faunal mass extinction horizon. The os-tracod assemblages identified at the Chongyang section are obviously different from those previously reported in the contem-poraneous microbialites in Guangxi and Chongqing regions, not only in the ostracod components but also in the abundance of filter-feeding ostracods relative to the deposit-feeding ostracods, an indicator of the oxygen level of the seawater. This spatial difference in ostracod assemblages might reflect the diversity of oceanic environmental conditions after the end-Permian mass extinction. Ostracods disappear at 200 cm below and near the main mass extinction horizon, and on the top of the microbialites, respectively, showing an episodic and gradual collapse process at the Chongyang section. The carbon isotope composition is found to appear at 200 cm below the main mass extinction horizon, indicating the initial deterioration of oceanic environment. Fluctuation of the carbon isotope composition is obviously related with the episodic evolution of ostracod species, but not with the abundance of ostracods.

关键词： ostracod microbialite Permian-Triassic mass extinction Chongyang

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Inclination Deepening of Paleogene Red Beds in the Qiangtang Terrane,the Hinterland of the Qinghai-Tibet Plateau

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地学前缘 2009年第S1期16卷 94-95页

作者： Bo Ran,Zhifei Liu,Chengshan Wang,Xixi Zhao,Yalin Li 1.College of earth sciences,Chengdu university of Technology,Chengdu 610059,china. 2.laboratory of Marine Geology,Tongji university,Shanghai 200092,china 3.state key laboratory of geological processes and mineral resources,Research Center for Tibetan Plateau Geology,china university of geosciences,Beijing 100083,china 4.Institute of Tectonics and earth sciences Department,university of California,Santa Cruz,CA 95064,USA

In this research,one hundred and ten samples（ten sampling localities）were drilled by a portable petrol-driven drill in the Tongtianhe area along the highway where developes Yaxicuo Group,Oligocene. Complete demagnetization were finished in university of California,Santa Cruz（UCSC）.These remanence data were collected:Dg=334.2,Ig=52.3,α95=7.1,k=7.3（before structural correction）;Ds=27.2, Is=66.6,α95=7.3,k=7.0（after structural correction）.

关键词： inclination deepening red beds Yaxicuo Group remagnetization

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High-pressure synchrotron x-ray diffraction and Raman spectroscopic study of plumbogummite

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Chinese Physics B 2018年第1期27卷 541-546页

作者：康端巫翔袁冠黄圣轩牛菁菁高静秦善 key laboratory of Orogenic Belts and Crustal Evolution Ministry of Education School of Earth and Space SciencesPeking University state key laboratory of geological processes and mineral resources China University of Geosciences

PbA13（PO4）2（OH,H20）6, an important environmental mineral, is in-situ studied by synchrotron x-ray diffraction （XRD） and Raman scattering combined with diamond anvil cells （DACs） at pressures up to - 11.0 GPa and room temper- ature. The XRD results indicate that plumbogummite does not undergo a phase transition between 0 GPa and 10.9 GPa. Moreover, the c axis is more compressible than the a axis, revealing its anisotropic behavior. The pressure-volume data are fitted to the third-order Birch-Murnaghan equation of state to yield the plumbogummite bulk modulus K0 of 68（ I ） GPa and KU of 6.1. The [PO4]3 and [HPO4]2 Raman vibrational modes exhibit scale nearly linearly as a function of pressure. The [PO4]3 stretching modes are generally more sensitive to pressure than the bending modes. The Grfineisen parameters range from -0.07 to 1.19, with an arithmetic mean of approximately 0.39.

关键词： plumbogummite equation of state Grfineisen parameter diamond anvil cell

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Gold Distribution in Tellurium-Rich Pyrite and Tellurides from the Xiaoqinling Gold District,Southern Margin of the North china Craton

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矿物学报 2009年第S1期29卷 113-114页

作者： BI Shi-jian1,2,LI Jian-wei1,2,LI Zhan-ke1,2,ZHANG Su-xin1,ZHENG Shu1(1. state key laboratory of geological processes and mineral resources,china university of geosciences,43.074 wuhan,china 2. faculty of earth resources,china university of geosciences,43.074 wuhan,china)

Gold is commonly associated with arsenic in As-rich pyrite or arsenopyrite in a variety types of gold deposit,such as sediment-hosted gold deposits,epithermal Au-Ag deposits,Au-rich VMS deposits,and mesothermal lode g... 详细信息

关键词： Gold Distribution in Tellurium-Rich Pyrite and Tellurides from the Xiaoqinling Gold District,Southern Margin of the North china

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Magnetic Structure of Continental Crust: Implications for Crustal Structure and Evolution

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Journal of earth Science 2000年第3期19卷 162-166页

作者： Liu Qingsheng The state key laboratory of Oil/Gas Reservoir Geology and Exploitation of china, Chengdu 610059, china Department of Geophysics, china university of geosciences, wuhan 43.074, china Gao Shan faculty of earth sciences, china Universit

Magnetic structure of the continental crust is one of the important geophysical aspects of continental lithosphere. This paper reviews the achievements in the research into the magnetic structure and its significance for crustal tectonics, composition, metamorphic facies, crust mantle interaction and magnetization of deep crust. Further studies are suggested according to the basic principles of rock and mineral magnetism in terms of petrology, geochemistry and structural geology. Emphasis is placed on new geological ideas and synthetic studies of the relationship between deep geological processes and interpretation of gravity, magnetic, electrical and seismic data. The relationships between magnetic, density, electricity, velocity, geothermal structures and deep geodynamic processes are taken as a system for the research into the deep geology.

关键词： magnetic structure metamorphic facies crust mantle interaction.

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Development of distributed time-variant gain model for nonlinear hydrological systems

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Science china earth sciences 2005年第6期48卷 713-723页

作者： XIA Jun1, 2, WANG Gangsheng1, TAN Ge1, YE Aizhong2 & G. H. Huang3 1. key laboratory of Water Cycle & Related Land Surface processes, Institute of Geographic sciences and Natural resources Research, Chinese Academy of sciences, Beijing 100101, china 2. state key laboratory of Water resources & Hydropower Engineering sciences, wuhan university, wuhan 430072, china 3. faculty of Engineering, university of Regina, 3737 Wascana Parkway, Regina, Sask., S4S 0A2, Canada Correspondence should be addressed to Xia Jun key laboratory of Water Cycle & Related Land Surface processes Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing China state key laboratory of Water resources & Hydropower Engineering sciences Wuhan University Wuhan China faculty of Engineering University of Regina Sask Canada

In this paper, a rainfall-runoff modeling system is developed based on a nonlinear Volterra functional series and a hydrological conceptual modeling approach. Two models, i.e. the time-variant gain model (TVGM) and the distributed time-variant gain model (DTVGM) that are built on the platform of Digital Elevation Model (DEM), Remote Sensing (RS) and Unit Hydro-logical Process were proposed. The developed DTVGM model was applied to two cases in the Heihe River Basin that is located in the arid and semiarid region of northwestern china and the Chaobai River basin located in the semihumid region of northern china. The results indicate that, in addition to the classic dynamic differential approach to describe nonlinear processes in hy-drological systems, it is possible to study such complex processes through the proposed sys-tematic approach to identify prominent hydrological relations. The DTVGM, coupling the advan-tages of both nonlinear and distributed hydrological models, can simulate variant hydrological processes under different environment conditions. Satisfactory results were obtained in fore-casting the time-space variations of hydrological processes and the relationships between land use/cover change and surface runoff variation.

关键词： hydrological process, nonlinearity, time-variant gain model, distributed hydrological model.

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Anatomical variations of living and fossil Liquidambar leaves:A proxy for paleoenvironmental reconstruction

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Science china earth sciences 2011年第4期54卷 493-508页

作者： XIAO Liang 1,2,3,4,SUN BaiNian 1,2,,LI XiangChuan 1,REN WenXiu 1 &JIA Hui 1 1 key laboratory of Western china's Environmental Systems of the Ministry of Education and College of earth and Environment Science,Lanzhou university,Lanzhou 730000,china 2 state key laboratory of Palaeobiology and Stratigraphy,Nanjing Institute of Geology and Palaeontology,Chinese Academy of sciences,Nanjing 210008,china 3 College of Arts and sciences,Bryant university,Smithfield RI 02917,U.S.A. 4 key laboratory of Western china's mineral resources and geological Engineering of Ministry of Education,Chang’an university,Xi’an 710054,china key laboratory of Western china’s Environmental Systems of the Ministry of Education and College of earth and Environment Science Lanzhou University Lanzhou China state key laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing China College of Arts and sciences Bryant University Smithfield USA key laboratory of Western china’s mineral resources and geological Engineering of Ministry of Education Chang’an University Xi’an China

Based on living ***,we have established that such epidermal cell properties as epidermal cell circumference(Circum.) ,undulation index(UI) ,epidermal cell area(EA) on both upper and lower epidermis and the corresponding epidermal cell density(ED) ,are suitable to differentiate between sun and shade ***,stomatal properties on the lower epidermis,including stomatal length(SL) ,stomatal pore length(PL) and the corresponding stomatal density(SD) ,are reliable parameters to identify sun/shade *** this anatomical approach was applied to 18 leaf remains of *** from the Miocene Xiannanshan Formation,Zhejiang Province(eastern china) ,and the fossil leaves were sorted into two groups,namely,sun and shade *** indicates that anatomical differences between sun and shade leaves found in living species could be used for fossil ***,the variation of UI between sun and shade morphotypes is larger on the upper epidermis as compared with the lower epidermis,showing that the UI on the upper epidermis is more sensitive to environmental *** addition,anatomical features are more variable in sun leaves than in shade leaves for both modern and fossil Liquidambar,suggesting sun leaves may be more sensitive to environmental *** leaves can then be a better indicator of paleoenvironmental ***,stomatal parameters of sun morphotype should be adopted on reconstructing paleoenvironments using Liquidambar leaf *** the other hand,the three-lobed fossil *** leaf assemblage in the Xiananshan Formation is represented by an almost similar percentage of sun and shade morphotypes(56%and 44%,respectively) ,which is attributed to the short transport before *** a result,identifying sun/shade morphotypes are very useful in reconstructing paleoenvironments based on fossil leaves of Liquidambar.

关键词： Liquidambar formosana Liquidambar miosinica leaf anatomy the Miocene Xiananshan Formation sun and shade leaves

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Constraints of authigenic carbonates on trace elements (Sr,Mg) of lacustrine ostracod shells in paleoenviron-ment reconstruction and its mechanism

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Science china earth sciences 2008年第5期51卷 654-664页

作者： HU Guang1,2, JIN ZhangDong1 & ZHANG Fei3 1 state key laboratory of Loess and Quaternary Geology, Institute of earth Environment, Chinese Academy of sciences, Xi’an 710075, china 2 Graduate university of the Chinese Academy of sciences, Beijing 100049, china 3 College of resources and Environmental Science, Nanjing Agricultural university, Nanjing 210095, china state key laboratory of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences Xi’an China Graduate university of the Chinese Academy of sciences Beijing China College of resources and Environmental Science Nanjing Agricultural University Nanjing China

Molar ratios of Mg/Ca and Sr/Ca were measured in two species of ostracod shells preserved in the upper core (15–55 m) of the Hequing Basin in Yunnan Province, southwest china. By correlating the molar ratios between Mg/Ca and Sr/Ca and comparing them with Sr concentrations of the sediments, we suggested that: (1) the molar Mg/Ca and Sr/Ca ratio variations in respective ostracod primo reflected the changes in its ambient water composition and ecology; (2) the molar Sr/Ca ratios responded better to the salinity change linearly than Mg/Ca without aragonite precipitation in the system, and otherwise there was no linear relation between them; and (3) the molar Sr/Ca ratios were mainly controlled by salinity and authigenic carbonate precipitation, whereas the molar Mg/Ca ratios were related to both salinity and temperature. In fact, the rate of ostracod growth owing to temperature controls the fluctuation of Mg/Ca in shells. Here, more attentions should be paid to the constraint of authigenic mineral precipitation processes on the trace elements in ostracod shells and to the correlation between these trace elements in biogenic carbonates and compositions of the sediments in systems and in future in vitro experiments.

关键词： ostracod shell molar Sr/Ca ratio molar Mg/Ca ratio environmental response Heqing Basin

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Petrogenesis and significance of early Yanshanian syenite-granite complex in eastern Nanling Range

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Science china earth sciences 2005年第7期48卷 912-924页

作者： CHEN Peirong1, ZHOU Xinmin1, ZHANG Wenlan1, LI Huimin2, FAN Chunfang1, SUN Tao1, CHEN Weifeng1 & ZHANG Min1 1. state key laboratory of mineral Deposits Research, Department of earth sciences, Nanjing university, Nanjing 210093, china 2. Tianjin Institute of Geology and mineral resources, china geological Survey, Tianjin 300170, china state key laboratory of mineral Deposits Research Department of Earth Sciences Nanjing University Nanjing 210093 China Tianjin Institute of Geology and mineral resources China Geological Survey Tianjin 300170 China

In the eastern Nanling Range there exists the early Yanshanian syenite-granite assemblage. A representative example is the Pitou-Tabei complex composed of the Tabei syenite pluton and the Pitou syenogranite pluton in southern Jiangxi Province. U-Pb zircon dating yields ages of 188.6±2.2 Ma for the Tabei pluton and 186.3±1.1 Ma for the Pitou pluton. The Tabei syenite is characterized by relatively low SiO2 content (62.40% - 68.75%), high alkalis (K2O+Na2O = 10.56%-11.96%), low percent K2O/Na2O ratios (0.56-0.93), metaluminous fea- ture (A/CNK = 0.80-1.00), enrichment in LILE (Rb, Ba, K) and HFSE (Th, U, Nb, Ta, Zr, and so on), weakly negative to positive Eu anomalies (δ Eu = 0.63-1.82), relatively low (87Sr/86Sr)i (0.70412-0.70543), and relatively high ε Nd(t) (3.14-3.52). The Pitou syenogranite is charac- terized by high silicon content (SiO2 = 71.06%-76.28%), relatively low alkalis (K2O+Na2O = 8.10%-9.80%), high percent K2O/Na2O ratios (1.22-1.94), metaluminous feature (A/CNK = 0.94-1.07), enrichment in Rb, Th (U), K, depletion in Ba, Nb, Ta, Sr, P , Zr, Ti, high ΣREE (av- eraging 451.03 μg/g), strong negative Eu anomalies (δ Eu = 0.27-0.33), relatively high (87Sr/86Sr)i (0.70805-0.70912), and relatively low ε Nd( t ) (?5.35-?6.29). The Tabei syenite and Pitou syenogranite both have the characteristics of A-type granites. The former is considered to be from the asthenosphere mantle, and the latter was the product of the crust-mantle mixture. They both were probably formed in a rifting setting.

关键词： syenite-granite assemblage single zircon U-Pb age rifting environment Nanling Range.

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Redevelopment of liftoff rates of saltating sand grains based on a simple optimization model

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Science china earth sciences 2010年第4期53卷 568-574页

作者： CHENG Hong & ZOU XueYong state key laboratory of earth Surface processes and Resource Ecology,Beijing Normal university,Beijing 100875,china MOE Engineering Center of Desertification and Blown-sand Control,Beijing Normal university,Beijing 100875,china key laboratory of Environmental Change and Natural Disaster of the Ministry of Education of china,Beijing Normal university,Beijing 100875,china state key laboratory of earth Surface processes and Resource Ecology Beijing Normal University Beijing China MOE Engineering Center of Desertification and Blown-sand Control Beijing Normal University Beijing China key laboratory of Environmental Change and Natural Disaster of the Ministry of Education of china Beijing Normal University Beijing China

This paper is a redevelopment result of liftoff rates of saltating sand grains based on our previous *** sand flow is a complex multi-phase flow because of a special two-phase gas-solid flow near ground *** extensive research on the movement of blowing sand,no model fully characterizes aeolian sand flow,and large differences often exist between simulations of aeolian sand movement and field *** key problem is a few of sufficient research on liftoff rates of saltating sand grains(also called the number of liftoff sand grains per unit time and per unit bed area).It is necessary to re-search in advance liftoff rates of saltating sand *** redeveloped liftoff rates of saltating sand grains by establishing an optimization model based on the flux of aeolian sand flow at different heights of the sampler in wind tunnel and the simulated capture of saltating sand grains by different heights of the sampler that are from different liftoff position(distance from the sampler) in order to revise previous inversion condition of liftoff rates of saltating sand *** rates increased rapidly with increasing wind *** frictional wind velocities of u=0.67,0.77,0.82,0.83,and 0.87 m s-1,liftoff rates were 3840,954502,5235114,5499407,and 7696291 sand grain s-1 m-2,*** rates could be expressed as the square of the instantaneous frictional wind velocity and a constant(0.663) that differs from the critical(threshold) frictional wind velocity at which saltation *** our results require additional experimental validation and the simple optimization model must be improved,they nonetheless provide a strong basis for future research.

关键词： liftoff rates of saltating sand grains optimization model wind tunnel two-phase gas-solid flow

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