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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 SuXin2. key laboratory of {2. and {3. {3. of ministry of education, wuhan 430074, China 2.State key laboratory of geological Processes and Mineral Resources, wuhan 430074, China key laboratory of {2. and {3. {3. of ministry of education Wuhan China State key laboratory of {2.logical 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 2.0 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 2.0 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

Sedimentary geochemistry of the Cambrian-Ordovician cherts: Implication on archipelagic ocean of North Qilian orogenic belt

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Science China Earth Sciences 2007年第11期50卷 1628-1644页

作者： DU YuanSheng1,2. ZHU Jie1, GU SongZhu1, 2. XU YaJun1 & YANG JiangHai1 1 Faculty of Earth Sciences, China university of geosciences,{2., China {3. {3. of biogeology and Environment geology of education ministry,{2., China Faculty of Earth Sciences China University of Geosciences Wuhan China key laboratory of {2. and Environment {3. of {3. ministry Wuhan China

The Caledonian North Qilian orogenic belt lies between the North China plate and the Qaidam mi-croplates, and resulted from the collision among the Qaidam microplate, mid-Qilian block and the North China plate. The orogen initiated from the rifting of the Late Proterozoic Rodinia, and then it experi-enced stages of Cambrian rift basin and Ordovician archipelagic oceanic basin, and foreland basin during Silurian to Early-Middle Devonian. The average ratios of Al/(Al+Fe+Mn), Al/(Al+Fe), δ Ce, Lan/Ybn and Lan/Cen from cherts of Cambrian Heicigou Formation are 0.797, 0.62., 1.114, 0.994 and 1.03. re-spectively. In the NAS standardized REE distribution pattern, the cherts from Xiangqianshan is slightly HREE enriched, and the cherts from Ganluci and Shiqingdong are plane. All of these features indicated that Cambrian cherts of the Heicigou Formation originated from a continental margin rift background. On the contrary, the average ratios of Al/(Al+Fe+Mn), Al/(Al+Fe), δ Ce, Lan/Ybn, Lan/Cen of the Ordovician chert from Dakecha, Cuijiadun, Shihuigou, Laohushan, Heicigou, Maomaoshan, Bianmagou, Da-chadaban, Baiquanmen, Jiugequan and Angzanggou, are respectively 0.72. 0.58, 0.99, 1.09 and 0.96 respectively. Their NAS standardized REE distribution patterns of most Ordovician cherts are plane mode or slightly HREE enriched. The REE distribution pattern of few samples of cherts are slightly LREE enriched. Characteristics of sedimentary geochemistry and tectonic evolution demonstrated that the Cambrian-Ordovician cherts, associated with rift, oceanic, island arc and back-arc volcanic rocks, was not formed in a typical abyssal oceanic basin or mid-oceanic ridge. On the contrary, they formed in a deepwater basin of continental margin or a archipelagic ocean tectonic setting. Several Early Paleo-zoic ophiolite belts in North Qilian and adjacent periphery Qaidam microplate imply that an archipelagic ocean during Ordovician existed in the east of Pro-Tethys.

关键词： North Qilian orogenic belt,Cambrian-Ordovician,cherts sedimentary geochemistry,archipelagic ocean

Analytical method of Cr stable isotope and its application to water pollution survey

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Chinese Science Bulletin 2010年第7期55卷 664-669页

作者： GAO YongJuan 1,2,3.MA Teng 4,5,LING WenLi 1,2,LIU CunFu 4,5 & LI Li 4,5 1Faculty of Earth Science,China university of geosciences,wuhan {3.,China 2State key {3. of geological Processes and Mineral Resources,China university of geosciences,wuhan {3.,China 3.Graduate School,China university of geosciences,wuhan {3.,China 4 Biogeological and environmental geology {3. of ministry of education(China university of geosciences) ,wuhan {3.,China 5 Sino-Hungary Joint {3. of environmental Sciences and Health,China university of geosciences,wuhan {3.,China Faculty of Earth Science China University of Geosciences Wuhan China State key laboratory of {2.logical Processes and Mineral Resources China University of Geosciences Wuhan China Graduate School China University of Geosciences Wuhan China Biogeological and environmental {2. {3. of {3. of education (China university of geosciences) Wuhan China Sino-Hungary Joint laboratory of environmental Sciences and Health China University of Geosciences Wuhan China

High Cr(VI) concentration is a potential serious risk to environment and ecologic ***,it is essential to effectively monitor Cr contamination in water systems and scientifically evaluate its evolution trend.A new method of in-situ tracer technique by Cr isotopic analysis for quantitatively estimating Cr-contamination and its regional evolution in natural waters as well as a case application are reported in this *** on documented literatures,an experimental procedure for chemical separation and purification of Cr in water samples and its analytical method for Cr isotopic measurement by thermal ionization mass spectrometry(TIMS) are *** samples collected around a chemical factory in Hubei Province were analyzed by this *** samples showδ53.r values ranging from-1.7‰to 7.3.and an elevating trend with an increasing in distance from the sampling site to pollution source.A functional correlation following Rayleigh fractionation law was established between sample'sδ53.r value and its extent of Cr *** study suggests that Cr isotopic analysis is an effective method to reveal the spatial distribution and its evolution trend of Cr contamination in the regional water *** is thus helpful to assessing the self-purifying ability of local water system according to Cr isotopic fractionation.

关键词：铬(VI) 水污染调查稳定同位素应用同位素分析供水系统演变趋势示踪技术

Endolithic fungi:A possible killer for the mass extinction of Cretaceous dinosaurs

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Science China Earth Sciences 2008年第6期51卷 801-807页

作者： GONG YiMing1,2. XU Ran1 & HU Bi2.1 key laboratory of {2. and {3. {3. of ministry of education, State key laboratory of geological Processes and Mineral Resources, China university of geosciences,{12., China 2.Institute of Resources and Environment key laboratory of Biogenic Traces & Sedimentary Minerals of Henan Province, Henan Polytechnic university, Jiaozuo 454003. China key laboratory of {2. and {3. {3. of ministry of education State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Wuhan China Institute of Resources and Environment key laboratory of Biogenic Traces & Sedimentary Minerals of Henan Province Henan Polytechnic University Jiaozuo China

Mycelium-like structures found under ESEM within radial sections of fragmental dinosaur eggshells would be the endolithic fungi coexistent with dinosaur eggs in the upper part of the Late Cretaceous Hugang Formation from the Wenjiaping section of Wenxian, Danjiangkou, northwestern Hubei, Central China. The endolithic fungi selectively occurred in the bad biomineral zone within the columnar layer of the eggshells, where the crowded endolithic fungi penetrated the columnar layer at near-vertical or near-horizontal angles. The endolithic fungi are needle-like, ribbon-like and silk-like, and 5–18 μm long, 0.3.0.5 μm wide at their base, with pointed tip, and are unbranched. The hyphae are mainly composed of oxygen, carbon and calcium, and are with minor sodium, potassium, chlorine and sulfur. The endolithic fungi and host have the same characters in lithification, fracture and main chemical composition. We suggested that the episode endolithic fungi invading dinosaur eggs may have taken place in the interval between after formation of dinosaur eggshells and before their petrification and that dinosaur eggs invaded by endolithic fungi would not be normally incubated or would only be incubated into venerable and pathologic baby dinosaurs to be easily to aborted and contributed to the mass extinction of the dinosaurs at the end of Cretaceous.

关键词： endolithic fungi dinosaur eggs mass extinction Cretaceous

Arsenic Biomobilization from Aquifer Sediments by Indigenous Bacteria at Datong Basin and Hetao Plain,Northern China

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地学前缘 2009年第S1期16卷 4-5页

作者： Zuoming Xie,Yanxin Wang School of environmental Studies & MOE key {2. of {3. and environmental geology,China university of geosciences(wuhan),wuhan 430074,China.

High arsenic groundwater is widely distributed at Datong Basin and Hetao Plain,northern *** investigate the effects of microbial activities on arsenic mobilization in the two high arsenic regions,the microcosm experiments were performed under various conditions of two bacterial strains(XZM001 and YH001,isolated from the two shallow aquifer sedi-

关键词： biomobilization indigenous bacteria As

Megaripples from the Mesoproterozoic of the Kimberley region,northwestern Australia and its geological implications

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Journal of Palaeogeography 2012年第1期1卷 15-25页

作者： Lan Zhongwu 1,2.3.,Zhong-Qiang Chen 2.4,1.State key {2. of Lithospheric Evolution,Institute of geology and {3.physics,Chinese Academy of Sciences,Beijing 10002.,China 2.School of Earth and Environment,The university of Western Australia,Australia 3.key Lab of Petroleum Resources Research,Institute of geology and {3.physics,Chinese Academy of Sciences,Beijing 10002.,China 4.State key {2. of {12. and environmental geology,China university of {3.sciences (wuhan),wuhan 430074,China State key laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China School of Earth and Environment The University of Western Australia Australia key Lab of Petroleum Resources Research Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China State key laboratory of {2. and {3. {3. China University of Geosciences (Wuhan) Wuhan 430074 China

Large ripples are described from the Mesoproterozoic Hilfordy Formation in the Kimberley region,northwestern *** ripple index (RI) and ripple symmetry index (RSI) suggest the Kimberley ripples were likely generated by storm *** wave height is up to 15 2.0}cm and wave length is up to 70 90 *** features,incorporated with other morphological characteristics such as symmetry,steepness,ripple spacing,and compositions,agree well with the megaripples previously reported from the intertidal-nearshore settings of modern seas and the geological *** Mesoproterozoic ripples were likely generated by the storm-induced *** survey of the global record of megaripples reveals that such structures have occurred through the geological past from the Archean to present *** were particularly common in the Neoproterozoic and had the largest ripple length and ripple height among the modern and geological *** is probably because extreme storms prevailed at that *** frequent occurrence in present day beach is probably due to the prevalence of extreme storms caused by the monsoon or tsunami/earthquake influenced climatic regimes.

关键词： megaripples palaeohydrodynamics extreme storms Mesoproterozoic Hilfordy Formation Kimberley northwestern Australia

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 {2. of Western China's environmental Systems of the {3. of {3. and College of Earth and Environment Science,Lanzhou university,Lanzhou 73.000,China 2.State key {2. of Palaeobiology and Stratigraphy,Nanjing Institute of geology and Palaeontology,Chinese Academy of Sciences,Nanjing 2.0008,China 3.College of Arts and Sciences,Bryant university,Smithfield RI 02.17,U.S.A. 4 key {2. of Western China's Mineral Resources and geological Engineering of {3. of {3.,Chang’an university,Xi’an 710054,China key laboratory of Western China’s {2. Systems of the {3. of {3. 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 {2.logical Engineering of {3. 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

Sorption behavior of U(VI), ^(2.0})U(VI) and ^(2.0})U(VI) onto fracture-filling clays in Beishan granite, Gansu: Application to selecting the site of high-level radwaste repository in China

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Science China Earth Sciences 2005年第10期48卷 1649-1655页

作者： MIN Maozhong1,2. LUO Xingzhang3. WANG Ju4, JIN Yuanxin4 & WANG Rucheng1 1. Department of Earth Sciences, State key {2. of Mineral Deposit Research, Nanjing university, Nanjing 2.0093. China 2. Center of Materials Analysis, Nanjing university, Nanjing 2.0093. China 3. Department of {3. Science and Engineering, Nanjing university, Nanjing 2.0093. China 4. Beijing geology Institute, Nuclear Industry, Beijing 10002., China Nanjing university Nuclear Industry

The first results of sorption experiments of U(VI), 2.0}U(VI) and 2.0}U(VI) onto original (unpurified) fracture-filling clays from No.1 monzonitic granite intrusion, Beishan area, Gansu Province, China are reported. The monzonitic granite intrusion is a potential location for a high-level radwaste (HLW) repository in China. The present experimental results show that the maximum U(VI) sorption reached 92. at near-neutral pH and the distribution coefficient (Kd) was 12.6 mL/g. A high sorption capacity of the fracture-filling clays in host rock on radioactive ele-ments is necessary for HLW deep {2.logical disposal repository. No preferential sorption of 2.0}U onto the clays was found. Finally, the sorption of U(VI) onto the clays was also modeled using a surface complexation model.

关键词： HLW geological disposal repository, granite, uranium, radionuclide, clay, sorption.

A Technique for Carbon and Chlorine Isotope Analyses of Chlorinated Aliphatic Hydrocarbons in Groundwater

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Journal of Earth Science 2013年第2期24卷 274-281页

作者：甘义群余婷婷周爱国刘运德刘存富 School of environmental Studies China University of Geosciences State key laboratory of {2. and {3. {3. China University of Geosciences

Chlorinated aliphatic hydrocarbons （CAHs）, significant contaminants in groundwater, can be characterized by stable isotopic compositions of carbon and chlorine. Previously published methods were of low analytical sensitivity or not ideal for natural samples with low concentrations of CAHs. This method is reported here to carry out simultaneously carbon and chlorine isotope analyses for mieromolar concentrations of dissolved CAHs. It was executed by extracting and converting CAHs to carbon dioxide and methyl chloride （CH3.I）. Specially, a continuous-flow interface GasBench Ⅱ was used to extract CH3.I for online chlorine isotope analysis. As a result, it greatly enhances the efficiency for isotope analysis by eliminating procedures for offline CH3.I preparation and separation. Sample size requirement was reduced to approximately 11 pmol chlorine. The standard deviation of δ^＋3. and δ^3.CI for both TCE solvents and water samples was better than 0.3.‰ and 0.2.%0 （1σ）, *** and chlorine isotope analyses can be used as an important tool to study the sources of organic contaminants in groundwater and their behaviors in the aquifers. The method is applicable to manufacturers＇ products as well as a sample from a polluted site in principle, which will be validated in our field studies.

关键词： chlorine isotope carbon isotope chlorinated aliphatic hydrocarbon (CAH) groundwater organic contamination.