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organic Carbon Isotope geochemistry of the Neoproterozoic Doushantuo Formation,South China

Acta Geologica Sinica(English Edition) 2006年第5期80卷 670-683页

作者： GUO Qingjun LIU Congqiang Harald STRAUSS Tatiana GOLDBERG ZHU Maoyan PI Daohui WANG Jian State Key laboratory of Environmental geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang Guizhou 550002 China Geologisch-Palaontologisches Institut Universitat Miinster Corrensstrasse 24 48149 Miinster Germany School of Earth Sciences James Cook University Townsville QLD 4811 Australia Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing Jiangsu 210008 China Guizhou Phosphorite Ore Company Weng＇an Guizhou

The Neoproterozoic Doushantuo Formation on the Yangtze Platform, South China, documents a sedimentary succession with different sedimentary facies from carbonate platform to slope and to deep sea basin, and hosts one of the world-class phosphorite deposits. In these strata, exquisitely preserved fossils have been discovered： the Weng＇an biota. This study presents carbon isotope geochemistry which is associated paired carbonate and organic matter from the Weng＇an section of a carbonate platform （shelf of the Yangtze Platform, Guizhou Province） from the Songtao section and Nanming section of a transition belt （slope of the Yangtze Platform, Guizhou Province） and from the Yanwutan section （basin area of the Yangtze Platform, Hunan Province）. Environmental variations and bio-events on the Yangtze Platform during the Late Neoproterozoic and their causal relationship are discussed. Negative carbon isotope values for carbonate and organic carbon （mean δ^13Corg = -35.0‰） from the uppermost Nantuo Formation are followed by an overall increase in δ^13C up-section. Carbon isotope values vary between -9.9‰ and 3.6‰ for carbonate and between -35.6‰ and -21.5‰ for organic carbon, respectively. Heavier δ^13Ccarb values suggest an increase in organic carbon burial, possibly related to increasing productivity （such as the Weng＇an biota）. The δ^13C values of the sediments from the Doushantuo Formation decreased from the platform via the slope to basin, reflecting a reduced environment with minor dissolved inorganic carbon possibly due to a lower primary productivity. It is deduced that the classical upwelling process, the stratification structure and the hydrothermal eruption are principally important mechanisms to interpret the carbon isotopic compositions of the sediments from the Doushantuo Formation.

关键词： Late Neoproterozoic Doushantuo Formation organic carbon isotopic composition the Yangtze Platform

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The Variation of Soil organic Matter in a Forest-Cultivation Sequ ence Traced by Stable Carbon Isotopes

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Chinese Journal Of geochemistry 2003年第1期22卷 83-88页

作者：刘启明王世杰朴河春欧阳自远 State Key laboratory of Environmental geochemistry Institute of geochemistry Chinese Academy of Sciences

On the basis of different photosynthetic pathways, there is a n obvious difference in 13C values between C 3 and C 4 plants. In terms of this characteristic, we analyzed the organic carbon content (forest lands: 1.81%-16.00%; farmland: 0.43%-2.22%) and 13C values (forestla nds:-23.86‰ - -27.12‰; farmland:-19.66‰ - -23.26‰) of three profile-soil sa mples either in farmland or in forestland near the Maolan Karst virgin forest, w here there were developed plant C 3 plants previously and now are C 4 plants. Results showed that the deforestation has accelerated the decomposition rate of soil organic matter and reduced the proportion of active components in soil orga nic matter and thus soil fertility.

关键词：生态系统土壤有机物 SOM 碳同位素示踪农作物

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Distribution and geochemical significance of trace elements in kerogens from Ediacaran–Lower Cambrian strata in South China

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Acta Geochimica 2023年第1期42卷 50-62页

作者： Qian Deng Guanyu Zhao Haozhe Wang Bin Cheng Zewen Liao State Key laboratory of organic geochemistry Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China CAS Center for Excellence in Deep Earth Science Guangzhou 510640China University of Chinese Academy of Sciences Beijing 100049China

Some trace elements(TEs),both bio-essential and redox-sensitive,are promising tracers of Earth’s surface *** an essential sedimentary organic matter,kerogen may have inherited and retained the key TEs from *** this study,the distribution of TEs in kerogens from two sections(Dongkanshang and Fengtan) in South China was analyzed to explore its biogeochemical significance during Ediacaran-Lower *** with V and Zn,the relative concentrations of Co,Ni,Cu,and Mo were generally higher in kerogens than in the whole *** of TEs in the kerogen was involved in the selective utilization of TEs by different organic precursors and the competition of sulfide in the depositional *** significant content of TEs in the kerogens from deep-water facies corresponded to a more negative δ^(13) Ckeras a result of the dominant taxa of chemo autotrophs with tremendous bioaccumulation potential for trace metals and the reduction conditions favorable for organic matter ***,the content variations of trace elements in the kerogens coincided with the rise and fall of the Ediacaran biota,implying that the trace elements might have played an important role in early life evolution.

关键词： Trace elements Kerogen Ediacaran-Early Cambrian Biogeochemical significance South China

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The Dynamics of organic Matter in Soil Size and Density Fractions Traced by Stable Carbon Isotopes

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Chinese Journal Of geochemistry 2003年第2期22卷 179-184页

作者：刘启明王世杰朴河春欧阳自远 State Key laboratory of Environmental geochemistry Institute of Geochemistry Chinese Academy of Sciences

On the basis of different photosynthetic pathways, there is an obvious difference in {δ+{13}C} values between C-3 plants and C-4 plants. In terms of this characteristic, we analyzed the {δ+{13}C} values in different size and density fractions from two profile-soil samples either in farmland and forestlands near the Maolan Karst virgin forest, Southwest China, where there were developed C-3 plants previously and now are C-4 plants. Results showed that the δ+{13}C values of different size fractions in forestland soil are δ+{13}C-{coarse sand}{δ+{13}C-{fine sand}}>δ+{13}C-{coarse silt}>δ+{13}C-{clay}>δ+{13}C-{fine silt}, indicating that soil organic matter is fresh in coarse sand and oldest in fine silt. The δ+{13}C values of different density fractions in forestland soil are δ+{13}C-{light}{δ+{13}C-{heavy}}, indicating that the soil organic matter is fresh in light fractions and old in heavy fractions .

关键词：土壤成分有机物质土壤粒级土壤密度示踪稳定碳同位素

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Lipids of sulfate-reducing bacteria and sulfur-oxidizing bacteria found in the Dongsheng uranium deposit

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Chinese Science Bulletin 2012年第12期57卷 1311-1319页

作者： JIANG Lei CAI ChunFang ZHANG YongDong MAO ShengYi SUN YongGet LI KaiKai XIANG Lei ZHANG ChunMing Key laboratory of Petroleum Resources Research Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China Graduate University of Chinese Academy of Sciences Beijing 100049China State Key laboratory of organic geochemistry Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China Department of Earth Science Zhejiang UniversityHangzhou 310027China Department of geochemistry Yangtze UniversityJingzhou 434023China

U-bearing sandstones from the Dongsheng deposit in Ordos Basin contain abundant C15-C18 fatty acids. The fatty acids may have been derived from modern and ancient organisms including organisms from the intervals of U mineralization. A certain amount of i15:0, a15:0, a17:0 fatty acids coexist with small amounts of i17:1ω7c and 10me16:0, characteristic biomarkers of Desulfovibrio and Desulfobacter sp., respectively. This indicates the existence of sulfate-reducing bacteria (SRB) in the sandstones. The presence of sulfur-oxidizing bacteria (SOB), such as Beggiatoa and Thioploca, is indicated by significant amounts of 16:1ω7c and 18:1ω7c fatty acids. The existence of the SRB in the deposit, as inferred from the fatty acids, is consistent with results from fossilized microorganisms and isotopic compositions of ore-stage pyrite. This suggests that the environment may have been favorable for the SRB to grow since ore formation (9.8-22 Ma). The bacteria may have degraded hydrocarbons directly, or indirectly utilized hydrocarbons degraded by oxic microbes in the deposits. This process may have produced 12C-rich calcite and prominent baseline humps of unresolved complex mixtures (UCM), and 25-demethylated hopanes and tricyclic terpanes. The existence of sulfur-oxidizing bacteria and sulfate-reducing bacteria in the deposit may have resulted in bacterial sulfate reduction to sulfide, re-oxidization of the sulfide to sulfate and subsequent reduction of the sulfate to sulfide. This assertion is supported by ore-stage pyrite with δ34S values as low as-39.2‰, and the lightest sulfate (about 11‰) measured during the Phanerozoic, a difference of more than 46‰.

关键词：硫酸盐还原菌硫氧化细菌铀矿床不饱和脂肪酸微生物降解碳氢化合物脂类鄂尔多斯盆地

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Influences of ore formation on biomarkers in the Kupferschiefer from the Lubin mine, Poland

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Chinese Journal Of geochemistry 2005年第2期24卷 101-107页

作者：孙玉壮陈建平林明月孟志强张洪建 Hebei University of Engineering Handan 056038 ChinaOpen Laboratory of Organic Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China Key laboratory for Petroleum geochemistry CNPC Beijing 100083 China Hebei University of Engineering Handan 056038 China China University of Mining and Technology Xuzhou 221008 China

Molecular biomarkers are the important maturity parameters for sedimentary organic matter. They have also been widely used for determining the maturity of organic matter in ore deposits. However, during the study of organic matter in the Kupferschiefer from the Lubin mine, it had been found that the biomarkers were influenced by sulfide formation. In order to probe into the degree of influence on biomarkers, seven samples collected from a Kupferschiefer section from the Lubin mine were analyzed by various geochemical methods. The results indicated that in the samples with higher copper contents, the values of biomarkers are lower than in the samples with lower copper contents. In highly mineralized samples, hydrogen donation for thermochemical sulfate reduction (TSR) occurred in alkylated phenanthrenes and naphthalenes, leading to the decrease of 12 biomarker parameters during the Kupferschiefer mineralization.

关键词：分子生物标签甲基菲指数矿石信息卢布林沉积矿波兰

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A Thermal Event in the Ordos Basin:Insights from Illite ^40Ar-^39Ar Dating with Regression Analysis

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Journal of Earth Science 2018年第3期29卷 629-638页

作者： Longzhang Wang Liyun Wang Ping'an Peng Tongmo Dai Dayong Liu Key laboratory of Tectonics and Petroleum Resources of Ministry of Education China University of GeosciencesWuhan 430074China State Key laboratory of Geological Processes and Mineral Resources China University of GeosciencesWuhan 430074China State Key laboratory of organic geochemistry Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou 510640China

Four samples from a Permian reservoir in the Ordos Basin of North China were separated into twelve fractions in grain sizes of 〈0.5, 0.5-1 and 1-2 μm. Using the ^40Ar-^39Ar step-heating method, all of the fractions essentially yielded plateau ages ranging from 172.5 to 217.1 Ma. These scattered plateau ages might not have been obtained from pure diagenetic illites but from mixed clay minerals, although the samples were disaggregated using a gentle freeze-thaw cycle to free them of non-clay minerals. A regional thermal event, as suggested by several proxies, led to intensive iHitization as a distinct diagenetic process when the Yanshanian Movement triggered magmatism around the entire North China Block during the Jurassic to Cretaceous. Thermal illites formed during a short time period, whereas detrital illites came from various sources. The scattered plateau ages could have resulted from mixed degassing of thermal and detrital illites. Within one sample, the plateau ages decrease with the diminution of grain sizes, but it is difficult to extrapolate to the detrital-illite-free ages. Because the plateau age is a mixture of ages for thermal and detrital illites, this regression analysis studies the dependence of the plateau ages on the synthetic values of contents and ages of detrital illites instead of on the grain sizes. Comparing the samples to one another, the plateau ages show the same trend among the different grain sizes. Weighted by the contents and ages of detrital illites, linear regression analysis revealed the relationship between the plateau ages and the relative weight proportions. Based on iterated calculations, a thermal event age and a set of weight proportions were derived. The regressed thermal event age is 163.3±1.6 Ma, which coincides with regional thermal activities and links to gas accumulation.

关键词： thermal event ^40Ar-^39Ar dating of fllites linear regression analysis Ordos Basin.

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Environmental bioavailability:a potentially overlooked element in triggering antimicrobial resistance

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Science Bulletin 2022年第22期67卷 2269-2271页

作者： Han Yeong Kaw Jing Yu Xuejing Ma Bee Geok Yeo Lizhong Zhu Wei Wang Department of Environmental Science Zhejiang UniversityHangzhou 310058China Zhejiang Provincial Key laboratory of organic Pollution Process and Control Hangzhou 310058China laboratory of organic geochemistry(LOG) Tokyo University of Agriculture and TechnologyFuchu 183-8509Japan

Antimicrobial resistance(AMR)is unquestionably-one of the most severe,international public health crises that mankind faces now and in the next decades,with the latest data indicating global deaths quintuple over the past five years to claim nearly 5 million lives[1],which seems substantially underestimated the projected health impact(10 million deaths)and economic burden(US$100 trillion)of AMR by 2050[2].To counteract the burgeoning AMR crisis,the One Health initiative has called for international collective effort in improving human,animal and environmental health through integrated management of this interfacial *** which,the environmental dimension is often underrepresented,especially soil compartment as the origin,reservoir and transmission route for propagating antibiotic resistance genes(ARGs)in microbiota that exacerbate AMR[3].

关键词： collective reservoir resistance

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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, Chinese Academy of Sciences, Guangzhou 510640, 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.

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Past Century Fossil Fuel Burning Recorded by Tree-Ring δ13C and δ34S from Chaling,South China

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吉林大学学报(地球科学版) 2015年第S1期 371-372页

作者： Luhua Xie Peter M.Wynn Carly J.Stevens Baruch.Spiro Gangjian Wei Gan Zhang State Key laboratory of Isotope geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Key laboratory of Marginal Sea Geology Guangzhou Institute of Geochemistry Chinese Academy of Sciences Lancaster Environment Centre University of Lancaster Natural History Museum London UK State Key laboratory of organic geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences

工业革命以来由人类活动带来的大量化石燃料燃烧导致严重的环境污染,并引起气候变化。我国自1970年代开始大量排放人类活动产生的CO2和SO2,而且现在我国已经成为世界最大的CO2和SO2排放国。树轮碳-硫同位素及硫含量能很好地记录长时间... 详细信息

工业革命以来由人类活动带来的大量化石燃料燃烧导致严重的环境污染,并引起气候变化。我国自1970年代开始大量排放人类活动产生的CO2和SO2,而且现在我国已经成为世界最大的CO2和SO2排放国。树轮碳-硫同位素及硫含量能很好地记录长时间尺度的气候变化,水利用效率,及化石燃料燃烧。本摘要报道了来自南方森林115年全树树轮碳-硫同位素及硫含量,目的在于记录人类活动产生的CO2和SO2历排放历史,及试图探讨人类活动产生的CO2和SO2对树碳同位素及水利用效率的影响。结果显示树轮碳同位素自1940年代后期至2000年代后期持续下降,是由持续增加的化石燃料产生的CO2导致的;大气CO2校正后的树轮碳同位素反映了全年降雨量。此外,树轮细胞内CO2浓度及水利用效率自1940年代后期持续升高,其原因是大气CO2浓度增加。另一方面,树轮硫含量没有明显的变化,表明硫是树的基本元素,而硫同位素自1890年代后期以来持续下降,记录了化石燃料(北方煤)使用历史。与之前发表的数据,显示最近几年或几十年来树轮碳同位素的增加(1.2‰~2.5‰),但不能证明是由大气污染(SO2增加)引起的,因其被气候变化所掩盖。

关键词：树轮碳同位素硫同位素气候变化燃料燃烧 C and 人类活动时间尺度利用效率年降雨量

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