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Acta Oceanologica Sinica 2010年第3期29卷 116-126页

作者： WANG Aijun YE Xiang CHEN Jian Open laboratory for Coast and Ocean environmental {2. Third Institute of Oceanography State Oceanic Administration Xiamen 361005 China key laboratory of {2. of {2. for Coast and Island Development Nanjing University Nanjing 210093 China

In coastal environments, fine-grain sediments often aggregate into large and porous flocs. ElectroMagnetic Current Meters （EMCM） and Laser In Situ Scattering and Transmissometry （LISST-ST） have been deployed within a Spartina alterniflora marsh of the Luoyuan Bay in Fujian Province, China, to measure the current velocity, the floc size and the settling velocity between 15 and 2. January 2.08. During the observations, the near-bed water was collected in order to obtain the suspended sediment concentration （SSC） and constituent grain size. Data show that：（1） the nearbed current velocities vary from 0.1 to 5.6 cm/s in the central Spartina alterniflora marsh and 0.1–12.5 cm/s at the edge; （2. the SSCs vary from 4. to 188 mg/dm 3 . The mean grain size of constituent grains varies from 7.0 to 9.6 μm, and the mean floc sizes （MFS） vary from 30.4.to 69.4.μm. The relationship between the mean floc size and settling velocity can be described as： w s =ad b , in which w s is the floc settling velocity （mm/s）, a and b are coefficients. The floc settling velocity varies from 0.17 to 0.32.mm/s, with a mean value of 0.2. mm/s, and the floc settling velocity during the flood tide is higher than that during the ebb tide. The current velocity and the SSC are the main factors controlling the flocculation processes and the floc settling velocity.

关键词： Spartina alterniflora marsh current velocity suspended sediment concentration mean floc size floc settling velocity Luoyuan Bay

Geochemical Evidence of Gas Sources of CO_2.Rich Cold Springs from Wudalianchi,Northeast China

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Journal of Earth Science 2009年第6期20卷 959-970页

作者：毛绪美王焰新 Oleg V Chudaev 王逊 key laboratory of {2. and {2. {4. of {4. of education China University of GeosciencesWuhan Far East Geological Institute Russian Academy of Science Institute of Hydrogeology and Engineering geology of Heilongjiang Province

CO2.rich cold springs occur near the active volcanoes at Wudalianchi （五大连池）, Northeast China. The springs are rich in CO2. with HCO3-as the predominant anion and have elevated contents of total dissolved solid （TDS）（〉1 000 mg/L）, Fe^2. （〉2. mg/L）, Sr （〉1 mg/L）, and dissolved Si （〉2. mg/L）. The compositions of escaped and dissolved gases of the springs are similar. The δ^13C values of escaped gases and dissolved gases in mineral springs at Wudalianchi vary from -8.77‰ to -4.53‰ and -8.2.‰ to -5.2.‰, while δ^18O values vary from -10.68‰ to -7.65‰ and -10.30‰ to -8.84., respectively, indicating the same upper mantle origin of CO2.of escaped gases and dissolved gases in the springs. Carbon and oxygen isotope fractionations and water-CO2.exchange were weak in the process of groundwater flow. The 4.e content exceeds 5 000×10-6 cm^3·STP/mL in escaped gases of the mineral springs, and the 3He/4.e ratios of the escaped and dissolved gases vary from 2.64.a to 3.87Ra and 1.18Ra to 3.30Ra, respectively. It can be postulated that the CO2.of mineral springs deriving from the magma chamber of the upper mantle moves upward to the surface, to increase the content of 4.e in the mineral springs and decrease the ratio of 3He/4.e. The helium origin of escaped gases in springs can be calculated with the MORB-crust mixing model, but that in the north spring can be better explained with the MORB-crust-air mixing model due to the effect of mixing with surface water. However, dissolved helium in springs, except the north spring, is better explained with the MORB-crust-ASW mixing model.

关键词： δ^13C δ^18O, ^3He/^4.e mineral spring CO2 Wudalianchi Northeast China.

A possible Younger Dryas-type event during Asian monsoonal Termination 3

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Science China Earth Sciences 2006年第9期49卷 982-990页

作者： CHEN Shitao1, WANG Yongjin1, KONG Xinggong1, LIU Dianbing1, CHENG Hai2.& R.L. Edwards2.1. College of Geography Science, Nanjing Normal University, Jiangsu key laboratory of {2. Change and Ecological Construction, Nanjing 2.0097, China 2. Department of {2. and Geophysics, University of Minnesota, Minneapolis MN554.5, USA 1. College of Geography Science Nanjing Normal University Jiangsu Key Laboratory of Environmental Change and Ecological Construction Nanjing 210097 China 2. Department of geology and Geophysics University of Minnesota Minneapolis MN 55455 USA

Seven U-Th dates, 560 δ 18O data and microscopic sequences were measured for sta- lagmites from two high-altitude caves in Shennongjia area, Hubei Province. Variations of the de- cadal-resolution stalagmite δ 18O record from Swan Cave (1600 m elevation) reflect large spatial changes in circulation strength and precipitation of Asian monsoon. The evidence comes from a great similarity among the stalagmite δ 18O records from Nanjing, Jiangsu Province; Libo, Guizhou Province and here studied area during the last deglaciation, including a part interval of Younger-Dryas event and Bolling-Allerod. A 30-year-resolution stalagmite δ 18O record from Yongxing Cave (14.0 m eleva- tion), 70 km away from Swan Cave, reveals a rapid transition of Asian monsoon climate during Ter- mination 3 at about 2.5±5 kaBP. Based on 3 U-Th dates and about 5000 continuous annual bands, a millennial dry episode has been observed during Asian monsoonal Termination 3 from the Yongxing δ 18O profile. With respect to its structure, duration and transition, the dry reversal, as indicated by our stalagmite δ 18O record, generally agrees with the pattern of the YD event well-expressed in the Chi- nese stalagmite δ 18O records. This YD-type event is characterized by a large decrease in δ 18O value as much as 2.30‰, more than half of the δ 18O excursion between glacial/interglacial periods, and lasts 1371±59 a determined by the annual counting chronology. After this event, the monsoon climate shifted abruptly into the interglacial period within 74.4.a. Our data corroborate the view that the re- peated occurrence of YD-type event was not an “accident”, possibly resulted from the coupling of ice-sheet and oceanic/atmospheric circulations.

关键词： stalagmite, Termination 3, Asian monsoon, YD-type event, Shennongjia, Hubei Province.

Ce Anomalies of the Yangtze Region,South China,through the Ordovician and Silurian Transition

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Journal of Earth Science 2009年第6期20卷 941-948页

作者：严德天张丽琴李双建 key laboratory of Tectonics and Petroleum Resources of {2. of {2. China University of GeosciencesWuhan Institute of geology and Geophysics Chinese Academy of Sciences School of Geodesy and Geomatics Wuhan University key laboratory of Geospace Environment & Geodesy of {2. of {2. Wuhan University Petroleum Exploration and Production Institute of SINOPEC

Systematic Ce anomalies for whole-rock have been obtained from the shale-dominated, continuous, and pelagic sedimentary sequences spanning the Ordovician/Silurian （O/S） boundary at the Tieshui （铁水） of Xiushan （秀山）, Chongqing （重庆）, South China. Ce anomalies across the O/S boundary are recognized in three intervals, Wufeng （五峰）, Guanyinqiao （观音桥） and Longmaxi （龙马溪）. The calculated Ce/Ce＊ values of Wufeng Formation range from 0.84.to 0.96 （avg. 0.90）. In the Guanyinqiao Formation, the values of calculated Ce/Ce＊ range from 0.73 to 0.85 （avg. 0.79）. The Ce/Ce＊ values of uppermost Longmaxi Formation range from 0.87 to 0.96 （avg. 0.91）. All along the section, the magnitude of the Ce anomaly is always negative, but is more significant in the Guanyinqiao Formation. The relatively higher Ce/Ce＊ values in the Wufeng and Longmaxi shales are likely to be due to the sediments deposited under rather reducing conditions. The Ce anomaly apparently does play some regular roles in the anoxic events that accompany prominent mass extinctions, and this work provides new data of critical importance for constraining models on the end-Ordovician anoxic events and mass extinctions.

关键词： Ce anomaly redox mass extinction Ordovician/Silurian boundary Yangtze platform.

Organic geochemical characterization and depositional paleoenvironments of the Devonian strata in Guizhong region,Guangxi,China

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Science China Earth Sciences 2009年第S1期52卷 88-95页

作者： MAO ZhiChao1,2.DU YuanSheng1,ZHANG Min2.YAN JiaXin1 & ZENG Fang2.1 key {4. of {2. and Environment {2. of education {4.,wuhan 43.074,China 2.Department of Geochemistry,Yangtze University,Jingzhou 4.4.2.,China 1. key laboratory of {2. and Environment {2. of {4. {4. Wuhan 430074 China 2. Department of Geochemistry Yangtze University Jingzhou 434023 China

Devonian strata in the Guizhong region,Guangxi,China consist mainly of marine deposition carbonates(limestones and dolomites) as well as restricted clastic rocks. The strata thickness is measured as 2.4.m and classified into 14.formations. An integrated field geological,petrographic,sedimentological,palaeobiological,and geochemical study of these strata reveals that the depositional paleoenvironments were carbonate tidal flat,restricted platform,open platform,shelf,platform margin slop,and algal herm. The total organic carbon(TOC) of sedimentary organic matter ranges between 0.07% and 1.96% with average of 0.2.%. The organic matter types are Type ? and Type II1. The vitrinite reflectance(R0) of kerogen ranges between 0.99% and 2.03%,indicating the maturated and highly maturated stages. The analytical results of the representative samples collected from shelf and subtidal facies show that the differences of organic matter type and biological diagnostic compounds are related to the types of source rocks deposited in different paleoenvironments.

关键词： Guangxi Devonian system depositional environment sedimentary organic matter biomarker compounds

Spatial Distribution of OCPs in the Soils of Yangtze River Coast in Chongqing,China

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Spatial Distribution of OCPs in the Soils of Yangtze River C...

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

2.07中国科协年会

作者： Li Jie Qi Shihua Wang Xiangqin Li Jun key laboratory of {2. and {2. {4.,{4. of education,China University of Geosciences,wuhan 43.074,China

Concentrations of HCHs (hexachlorocyclohexane) and DDT (Dichlorodiphenyltrichloroethane) were determined in shallow subsurface (0-5cm depth) and deep soil layers (5-2.cm depth)from sliols of Yangtze river coast in Chongqing,*** of total HCHs (including α-HCH,β-HCH,γ-HCH,δ-HCH) and total DDTs (including p,p-DDE p,p-DDD o,p-DDT and p,p-DDT) in shallow subsurface soils ranged from 0.185 to 1.374.ng/g(mean 0.4.9ng/g) and 0.807 ng/g to 38.2.1ng/g (mean 7.2.4.g/g),respectively,and those in the deeper layers were 0.0795 to 1.692.ng/g (mean 0.564.ng/g),and from 0.308 to 88.306 ng/g (mean 13.718 ng/g), *** spatial distribution of HCHs and DDTs reflected the contamination of HCHs in this region probably came from local use of lindane and also indicated new lindane inputsin the past several years and DDT residues are from“old”sources.

关键词： spatial distribution Organochlorine pesticides Chongqing

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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 {2. {4. 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 （CH3CI）. Specially, a continuous-flow interface GasBench Ⅱ was used to extract CH3CI for online chlorine isotope analysis. As a result, it greatly enhances the efficiency for isotope analysis by eliminating procedures for offline CH3CI preparation and separation. Sample size requirement was reduced to approximately 11 pmol chlorine. The standard deviation of δ^＋3C and δ^37CI for both TCE solvents and water samples was better than 0.30‰ 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.

environmental archaeology of the Dachang region in the Daning Valley,the Three Gorges reservoir region of the Yangtze River,China

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Chinese Science Bulletin 2008年第S1期53卷 140-152页

作者： ZHANG Yun 1 &ZHU Cheng 2.1 State key laboratory of Vegetation and {2. Change,Institute of Botany,Chinese Academy of Sciences,Beijing 100093, China 2.School of Geographic and Oceanographic Sciences,Nanjing University,Nanjing 2.0093,China 1. State key laboratory of Vegetation and {2. Change Institute of Botany Chinese Academy of Sciences Beijing 100093 China 2. School of Geographic and Oceanographic Sciences Nanjing University Nanjing 210093 China

environmental archaeology of archaeological sites on both sides of the Dachang section in the Daning River,the Three Gorges of the Yangtze River,shows that riverbed evolution has a great influence on the distribution of archaeological sites during the prehistorical and historical period,and it restricts human activity and the development of ancient *** investigation,dating data,paleocurrent analysis of 100 gravels on the riverbed and archaeological excavation reveal that the riverbed of the Dachang section developed in the Shuangyantang region during the early stage,after about 30 kaBP it shifted westward gradually and reached the present *** with the westward shift,the focus of ancient culture changed for several *** the Western Zhou Dynasty's period,the east riverbank of the Daning River was the main residential *** the Han Dynasty,along with the westward shift,the living space of ancient people was no longer confined to the east riverbank and the focus of culture moved *** the Zhangjiawan site became the main dwelling *** the late Han Dynasty, the villages were flooded and the ancients had to immigrate to a high *** of the Han and the Jin Dynasties outcropped on the flood plain of the east bank because their surface sediments were eroded by several flood events and the westward shift of the riverbed.

关键词： the Daning River environmental archaeology the Shuangyantang site the Zhangjiawan site tombs of the Han and the Jin Dynasties

Variations in carbon isotope ratios of C_3 plants and distribution of C_4.plants along an altitudinal transect on the eastern slope of Mount Gongga

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Science China Earth Sciences 2009年第10期52卷 1714-1723页

作者： LI JiaZhu1, WANG GuoAn2. LIU XianZhao1, HAN JiaMao3, LIU Min4.& LIU XiaoJuan2.1 College of Geography and Planning, Ludong University, Yantai 2.4.2., China {4. laboratory of Plant-Soil Interactions, {2. of education, College of Resources and {4. Sciences, China Agri- cultural University, Beijing 100193, China 3 Institute of geology and Geophysics, Chinese Academy of Sciences, Beijing 10002., China 4.College of {4. Sciences, MOE laboratory for Earth Surface Processes, Peking University, Beijing 100871, China College of Geography and Planning Ludong University Yantai 264025 China key laboratory of Plant-Soil Interactions Ministry of Education College of Resources and Environmental Sciences China Agricultural University Beijing 100193 China Institute of geology and Geophysics Chinese Academy of Sciences Beijing 100029 China College of environmental Sciences MOE Laboratory for Earth Surface Processes Peking University Beijing 100871 China

Variations in carbon isotopic ratios (δ 13C) of C3 plants and distribution of C4.plants were investigated along an altitudinal transect on the eastern slope of Mount Gongga, and the environmental effects on them were discussed. It is shown that plants with C4.photosynthetic pathway mainly occur at altitudes below 2.00 m a.s.l., suggesting that the low summer temperature is responsible for the distributional pattern. In addition, δ 13C of C3 plants increases with elevation at the region above 2.00 m a.s.l. with the characteristics of humid climate, and the increase rate in δ 13C for C3 plants is about 1.3‰ per kilometer. Temperature determines the altitudinal trend of δ 13C.

关键词： Mount Gongga carbon isotopic ratios C3/C4 plants C4 distribution altitude

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High-resolution carbon isotope record for the Paleocene-Eocene thermal maximum from the Nanyang Basin,Central China

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High-resolution carbon isotope record for the Paleocene-Eoce...