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isotope Geochemistry of Volcanic Rocks from the Barton Peninsula,King George Island,Antarctica

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Journal of Earth Science 2011年第1期22卷 40-51页

作者： Jeong Hwang 郑祥身 Edward M Ripley Jong-Ik Lee Dongbok Shin Department of Geological Engineering Daejeon University Institute of Geology and Geophysics Chinese Academy of Sciences Department of Geological Sciences Indiana University Korea Polar Research Institute Department of Geological Sciences Kongju University

C, O, H, S and Sr isotopes were investigated to characterize the isotopic composition of the Paleocene-Eocene volcanic rocks in Barton Peninsula, King George Island, Antarctica. The analyzed samples of volcanic rocks cover a range from basalt to andesite. The δ 13C and 61SO values of calcite in volcanic rocks range from -7.5‰ to -3.2‰ and 0.4‰ to 5.1‰, respectively. The homogenous δ 13C cal and depleted δ18 Ccal values relative to primary magmatic values reflect the effect of high temperature alteration of volcanic rocks. The δ18 O of volcanic rocks ranges from -1.1‰ to 7.2‰, and the majority of values are significantly lower than those of primary magmatic values. The low δ18 O WR values are compatible with high temperature alteration. The initial values of 87Sr/86Sr of volcanic rocks span a narrow range from 0.703 312 to 0.703 504 which belong to the present mid-oceanic ridge basalt. The values of 87Sr/86Sr of volcanics in the Barton Peninsula are similar to those determined in the Fildes Peninsula, King George Island. The δD WR and H2O contents of volcanic rocks range from -74‰ to -66‰ and 0.67 wt.% to 2.74 wt.%, respectively. The higher δD WR and H2O wt.% of volcanic rocks relative to fresh basalts also result from high temperature alteration. Sulfur isotope compositions of the volcanic rocks range from -12.5‰ to -7.0‰; these values may represent fractionation accompanying partial oxidation of magmatic S or incorporation of some bacteriogenic sulfide. The low S contents and negative correlation with C and H2O reflect the formation of calcite and breakdown of sulfide as a result of high temperature water-rock interaction.

关键词： isotope volcanic rock high temperature alteration Antarctica.

isotope geochronology of Dapingzhang spilite-keratophyre formation in Yunnan Province and its geological significance

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Science China Earth Sciences 2000年第2期43卷 200-206页

作者：钟宏胡瑞忠叶造军涂光炽 1. Institute of Geochemistry Chinese Academy of Sciences 550002 Guiyang China 2. Institute of Geology Chinese Academy of Sciences 100029 Beijing China

On the basis of the geological field investigations and isotope geochronological studies the Sm-Nd isochron age (513 Ma?0 Ma), Rb-Sr isochron age (511 Ma? Ma) and K-Ar age (312-317 Ma) of the Dapingzhang spilite-keratophyre formation in Yunnan Province are presented. From these geochronological data it is evidenced that this suite of volcanic rocks was formed in the Cambrian and the parent magma was derived from a depleted mantle, which was influenced by crustal contamination and/or seawater hydrothermal alteration. During the Late Carboniferous the volcanic rocks experienced relatively strong geological reworking. This study provides geochronological evidence for the occurrence of Cambrian volcanic rocks in the Sanjiang (three-river) area.

关键词： spilite-keratophyre formation isotope geochronology Cambrian Dapingzhang Yunnan.

Stable-isotope probing of bacterial community for dissolved inorganic carbon utilization in Microcystis aeruginosa-dominated eutrophic water

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Journal of Environmental Sciences 2019年第5期31卷 264-272页

作者： Weiguo Zhang Jiangye Li Chengcheng Wang Xue Zhou Yan Gao Zhongjun Jia Institute of Agricultural Resources and Environment Jiangsu Academy of Agricultural Sciences Key Lab of Food Quality and Safety of Jiangsu Province-State Key Laboratory Breeding Base China Ministry of Agriculture Key Laboratory at Yangtze River Plain for Agricultural Environment College of Resources and Environmental Sciences Nanjing Agricultural University College of Water Conservancy and Hydropower Engineering Hohai University Institute of Soil Science Chinese Academy of Sciences

Dissolved inorganic carbon(DIC) is an important source of carbon in aquatic ecosystems,especially under conditions of increased frequency of cyanobacterial bloom. However, the importance of bacteria in direct or indirect utilization of DIC has been widely overlooked in eutrophic freshwater. To identify the functional bacteria that can actively utilize DIC in eutrophic freshwater during cyanobacterial bloom, stable-isotope probing(SIP) experiments were conducted on eutrophic river water with or without inoculation with cyanobacteria(Microcystis aeruginosa). Our 16 S rRNA sequencing results revealed the significance of Betaproteobacteria, with similar relative abundance as Alphaproteobacteria, in the active assimilation of H^(13)CO^(3-) into their DNA directly or indirectly, which include autotrophic genera Betaproteobacterial ammonia-oxidizing bacteria. Other bacterial groups containing autotrophic members, e.g. Planctomycetes and Nitrospira, also presented higher abundance among free-living bacteria in water without cyanobacteria. Microcystis aggregates showed a preference for some specific bacterial members that may utilize H^(13)CO^(3-) metabolized by Microcystis as organic matter, e.g. Bacteroidetes(Cytophagales, Sphingobacteriales), and microcystindegrading bacteria Betaproteobacteria(Paucibacter/Burkholderiaceae). This study provides some valuable information regarding the functional bacteria that can actively utilize DIC in eutrophic freshwater.

关键词： Dissolved inorganic carbon Stable isotope probing Eutrophication Microcystis aeruginosa

isotope and hydrochemical study of seawater intrusion in Laizhou Bay, Shandong Province

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Science China(Technological Sciences) 2001年第S1期44卷 86-91页

作者：张寿全戴福初 Chinese Acad Sci Inst Geol & Geophys Beijing 100029 Peoples R China Chinese Acad Sci Inst Geog Beijing 100101 Peoples R China

Seawater intrusion on the northern coast of Laizhou City is featured by "three sources and three dimensions". Modern sea water, ancient saline water and brine contained both in the Quaternary aquifer and in the bedrock fissures or crevice have been identified as possible sources. The ratio of γSO4/γCI is used to distinguish the origin of the different types of saline water. The correlation between 3H and y SO4/γ Cl provides a quantitative differentiation on the origin of the saline water, which makes it possible to take counter protection measures in different areas affected by sea water intrusion.

关键词： isotope seawater intrusion ratio of γSO4/γCl tritium.

isotope constraints on the hydraulic relationship of ground-waters between Quaternary and Tertiary aquifer in Xi'an area,Shaanxi province

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Science China(Technological Sciences) 2001年第S1期44卷 72-79页

作者：秦大军陶书华 Chinese Acad Sci Inst Geol & Geophys Beijing 100029 Peoples R China Shaanxi Bur Geol & Mineral Resources Hydrogeol & Engn Geol Team 1 Xian 710068 Peoples R China

isotope techniques are increasingly used in evaluating the hydraulic connections between groundwaters in different aquifers, and can improve the geological and hydrogeological database. In the Xi’an area, the upper Quaternary aquifer may have hydraulic connection with the lower aquifer, the Tertiary aquifer, based on geological analyses. δ2H, δ18O, 3H, and 14C data of groundwater samples provide further evidence for the existence of the hydraulic connection between both aquifers.

关键词： isotope hydraulic connection two aquifers Xi’an area.

Impact of municipal solid waste incineration on heavy metals in the surrounding soils by multivariate analysis and lead isotope analysis

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Journal of Environmental Sciences 2019年第8期31卷 47-56页

作者： Yang Li Hua Zhang Liming Shao Xiaoli Zhou Pinjing He State Key Laboratory of Pollution Control and Resource Reuse Tongji University Institute of Waste Treatment and Reclamation Tongji University Shanghai Institute of Pollution Control and Ecological Security Centre for the Technology Research and Training on Household Waste in Small Towns & Rural Area Ministry of Housing Urban-Rural Development

Municipal solid waste(MSW) incineration has become an important anthropogenic source of heavy metals(HMs) to the environment. However, assessing the impact of MSW incineration on HMs in the environment, especially soils, can be a challenging task because of various HM sources. To investigate the effect of MSW incineration on HMs in soils, soil samples collected at different distances from four MSW incinerators in Shanghai, China were analyzed for their contents of eight HMs(antimony, cadmium, chromium, copper,lead, mercury, nickel, and zinc) and lead(Pb) isotope ratios. Source identification and apportionment of HMs were accomplished using principal component analysis and Pb isotope analysis. Results indicated that the relatively high contents of cadmium, lead,antimony, and zinc in the soils at 250 m and 750–1250 m away from the MSW incinerators were related to MSW incineration, while the elevated contents of the other four HMs were associated with other anthropogenic activities. Based on Pb isotope analysis, the contribution ratio of MSW incineration(which had been operated for more than 14 years)to the accumulation of Pb in soil was approximately 10% on average, which was lower than coal combustion only. Incinerator emissions of Pb could have a measurable effect on the soil contamination within a limited area(≤1500 m).

关键词： Municipal solid waste incineration Soils Heavy metals Source identification Pb isotope ratios

isotope Method for Confined Groundwater Recharge of the Lower Reaches of the Heihe River,Inner Mongolia,China

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Acta Geologica Sinica(English Edition) 2007年第4期81卷 668-673页

作者： CHEN Jiansheng ZHAO Xia FAN Zhechao and WANG Jiyang 1 State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering,Hohai University,Nanjing 210098,China 2 Institute of isotope Hydrology Research,Hohai University,Nanjing 210098,China 3 Institute of Geology and Geophysics,Chinese Academy of Science,Beijing 100018,China State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai University Nanjing 210098 China

Environmental isotopes have been appfied to analyze confined groundwater recharge in the lower reaches of the Heihe River, Inner Mongolia. CFC is regarded as a tracer that determines the date of groundwater, the date being less than 45 a. The confined groundwater within the Gurinai area and Ejin Basin other than the surface water of Heihe River might have originated from precipitation from Qilian Mountain or/and the Tibetan Plateau. The deep confined groundwater overflows into an upper aquifer and emerges into the ground, forming springs and lakes within the low-lying area. The recharge volume is estimated to be around 400 million-cubic meters.

关键词： isotope CFC Ejin Basin Gurinai groundwater recharge precipitation Qilian Mountain

Timing the termination of the Doushantuo negative carbon isotope excursion: evidence from U-Pb ages from the Dengying and Liuchapo formations,South China

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Science Bulletin 2018年第21期63卷 1431-1438页

作者： Mingzhong Zhou Taiyi Luo Warren D.Huff Zhiqing Yang Guanghong Zhou Tian Gan Hua Yang Di Zhang School of Geographical and Environmental Sciences Guizhou Normal University State Key Laboratory of Ore Deposit Geochemistry Institute of Geochemistry Chinese Academy of Sciences Department of Geology University of Cincinnati Beijing SHRIMP Center Chinese Academy of Geological Sciences School of Geography and Tourism Guizhou Education University College of Earth Sciences University of Chinese Academy of Sciences

The Doushantuo negative carbon isotope excursion(DOUNCE) is the largest known marine inorganic carbon isotope anomaly. The origin of this pronounced negative excursion is still an enigmatic issue that attracts geologists. Time constraints on the excursion are the critical information that would provide insight into its genesis. In previous decades, the timing of its termination has been constrained by the widely cited zircon U-Pb age of 550.5 ± 0.8 Ma for the tuff at the top of the Miaohe Member at the Jiuqunao section in the Yangtze Gorges area, South China. However, results of recent studies indicate that the reliability of this time constraint needs to be re-evaluated. Here, a geochronological study was carried out using two K-bentonites from Fanglong in South China. A K-bentonite in the lower Dengying Formation yielded a U-Pb age of 557 ± 3 Ma, while a K-bentonite in the basal Liuchapo Formation yielded an age of 550 ± 3 Ma. Based on regional correlations between the Ediacaran successions in South China,the age(557 ± 3 Ma) for the K-bentonite in the lower Dengying Formation may serve as a second critical timing constraint for the ending of the DOUNCE. Combined with available estimates of the DOUNCE duration, our new data indicate that the DOUNCE has a maximum onset age ～570 Ma.

关键词： Doushantuo formation Dengying formation Shuram carbon isotope excursion South China

Carbon isotope and environmental changes in lakes in arid Northwest China

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Science China Earth Sciences 2019年第8期62卷 1193-1206页

作者： Weiguo LIU Xiangzhong LI Zheng WANG Huangye WANG Hu LIU Bo ZHANG Huan ZHANG Institute of Earth Environment CASState Key Laboratory of Loess and Quaternary GeologyXi’an 710061China University of Chinese Academy of Sciences Beijing 100049China

The stable carbon isotope composition(δ13 C) of lacustrine sediments, which can record changes in past environmental conditions such as the C4/C3 terrestrial vegetation composition, has been widely used for the reconstruction of terrestrial ecosystems and global climate changes. It has also been widely used in paleolimnological studies in arid northwestern China. In recent years, however, an increasing number of studies have enriched the environmental significance reflected by the stable carbon isotope geochemistry of lakes;therefore, the interpretation of lake δ13 C variations in paleoenvironmental reconstructions should be carefully evaluated from various aspects. In this paper, previous studies from the past several decades on the lacustrineδ13 C variations in arid northwestern China were reviewed, and the possible mechanisms of the δ13 C variations were *** study will provide a reference for the application of carbon isotope geochemistry in paleoenvironmental reconstructions.

关键词： Carbon isotope Lake Arid region of northwestern China Total organic carbon Organic biomarkers