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Discovery of seep carbonate nodules as new evidence for gas venting on the northern continental slope of South china Sea

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Chinese Science Bulletin 2006年第10期51卷 1228-1237页

作者： CHEN Zhong1,2,3, YAN Wen1,2,3, CHEN Muhong1,3, WANG Shuhong1,2,3, LU Jun1,3, ZHANG Fan1,3, XIANG Rong1,3, XIAO Shangbin1,3, YAN Pin1,2,3 & GU Senchang1,2,3 1. South china Sea Institute of Oceanology, Chinese Academy of Sci-ences, Guangzhou 510301, china 2. Guangzhou Center for Gas Hydrate Research, Chinese Academy of Sciences, Guangzhou 510301, china 3. key laboratory of Marginal Sea geology, South china Sea Institute of Oceanology and Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510301, china South china Sea Institute of Oceanology Chinese Academy of Science Guangzhou China Guangzhou Center for Gas Hydrate Research Chinese Academy of Sciences Guanzhou China key laboratory of Marginal Sea geology South China Sea Institute of Oceanology and Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China

Seep carbonate nodules were firstlycollected from the southwestern Dongsha area onnorthern continental slope of South china Sea formineralogical and geochemical studies. The resultsof X-ray diffraction show that carbonate nodules arecomposed of Fe-rich domolite,siderite and a few cal-cite and aragonite, as well as a small quantity ofnon-carbonate minerals such as goethite, quartz andclay minerals. Fe-rich dolomite and siderite charac-terized by euhedral microcrystalline structure weredirectly precipitated at cold seeps. The δ 13C valuesfor Fe-rich dolomite and siderite in the bulk nodulesvary from ?18.24‰ to ?36.07‰, and the δ 18O valuesrange from 0.42 to 2.76‰. Their moderate depleted13C reflects that carbon origin is possibly thermoge- netic gas or mixed gas, which is evidence of gasventings in the seafloor. Moreover, massive wormtube fossils related to cold seeps were found on thesurfaces of carbonate nodules, and the conduitsand/or channels in semi-solidified nodules whichwere not filled by carbonate or sediment were alsoobserved. A preliminary conclusion is that activemicro gas venting with a conduit/channel diameterrange from 200 μm to 600 μm possibly exists inmodern seafloor of the carbonate nodule area.

关键词：渗出碳酸盐节碳氧同位素甲烷渗漏天然气水化物

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On-line measurements ofδ15N in biological fluids by a modified continuous-flow elemental analyzer with an isotope-ratio mass spectrometer

On-line measurements ofδ15N in biological fluids by a modif...

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中国科学院地质与地球物理研究所2008学术年会

作者： Xu Wang~(1*),Lianjun Feng~2,Fusong Zhang~2 and Zhongli Ding~1 1 key laboratory of Cenozoic geology and Environment,Institute of geology and Geophysics,Chinese Academy of Sciences, RO.Box 9825,beijing 100029,china 2 Lab for Stable isotope Geochemistry,Institute of geology and Geophysics,Chinese Academy of Sciences,RO.Box 9825, beijing 100029,china

A modified continuous-flow elemental analyzer coupled to an isotope-ratio mass spectrometer (modified EA-IRMS) was tested for on-lineδN measurement on urea solution and biological fluids (***).The elemental analyzer configuration was adapted by adding a U-shaped cold trap and an X-pattem four-way valve for on-line trapping/venting of water from the liquid *** indicate that theδN ratios show little variation(standard deviation(SD) = 0.05‰) with a sample size above the equivalent N yield of 0.2 mg urea(0.092 mg N) when the mass spectrometer conditions were carefully *** contrast,a significant logarithmic decrease inδN with sample size was observed but this can be offset by applying a linearity correction or blank correction when the sample size is between equivalent N yields of 0.05 and 0.2 mg *** blank correctedδN ratios give an overall precision of .16‰whereas the average precision forδN corrected using combined linearity and shift correction is 0.05‰.The relatively large variation in blank correctedδN values may be attributed to the variability of the blankδN in the ***,the blank correction should be carefully performed in routine *** a result,the linearity range of a modified EA-IRMS can be extended to a minimum sample size of 0.023 mg *** addition, the reproducibility of the new system is good,as indicated by the precision(2‰) for a set of standards and *** data show that fluids containing nitrogen can be successfully analyzed in the modified EA-IRMS.

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

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

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中国科学院地质与地球物理研究所第十届(2010年度)学术年会

作者： ZHU Min~(1,2*),DING ZhongLi~1,WANG Xu~1,CHEN ZuoLing~1,JIANG HanChao~3, DONG XinXin~1,JI JunLiang~4,TANG ZiHua~1 & LUO Pan~1 1 key laboratory of Cenozoic geology and Environment,Institute of geology and Geophysics,Chinese Academy of Sciences,beijing 100029, china 2 The Graduate University of Chinese Academy of Sciences,beijing 100049,china 3 State key laboratory of Earthquake Dynamics,Institute of geology,china Earthquake Administration,beijing 100029,china 4 key laboratory of Biogeology and Environmental geology,Ministry of Education,china University of Geosciences,Wuhan 430074,china

The Paleocene-Eocene thermal maximum(PETM) was a transient episode of global warming,associated with massive atmospheric greenhouse gas input that occurred at the Paleocene/Eocene *** and isotope stratigraphic studies indicate that the PETM event is well documented in the marl deposits of the Yuhuangding section in the Nanyang Basin,Central china,with a carbon isotope negative excursion of～6.1‰within 19-m-thick marl *** is the highest resolution record of the PETM so far found in the *** PETM event was triggered within 2-cm-thick marl sediments,with a decrease ofδC (stable carbon isotope ratio) from -3.2‰to -5.2‰,suggesting a massive methane hydrate release for a transient period that was possibly caused by a catastrophic event.A comparison between marine and terrestrial records indicates a"Three-Phase Model"for the PETM *** there is a rapid negative excursion in theδC record,followed by a slowly decreasing trend,and then a gradual positive recovery,corresponding respectively to a rapid dissociation of oceanic methane hydrate,followed by a slow release of methane and then the consumption of the released methane.

关键词： PETM carbon isotope greenhouse gases Nanyang Basin

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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 Biogeology and Environmental geology of Ministry 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＋（〉20 mg/L）, Sr （〉1 mg/L）, and dissolved Si （〉20 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 -8.24‰ to -5.26‰, 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 4He content exceeds 5 000×10-6 cm^3·STP/mL in escaped gases of the mineral springs, and the 3He/4He ratios of the escaped and dissolved gases vary from 2.64Ra 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 4He in the mineral springs and decrease the ratio of 3He/4He. 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/^4He mineral spring CO2 Wudalianchi Northeast china.

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Water Security Problem in North china: Research and Perspective

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Pedosphere 2005年第5期15卷 563-575页

作者： XIA Jun LIU Meng-Yu JIA Shao-Feng key laboratory of Water Cycle ＆Related Land Surface Processes Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 （China） State key laboratory of Water Resources ＆ Hydropower Engineering Sciences Wuhan University Wuhan 430072（China） Center for Agricultural Resources Research Institute of Genetic and Developmental Biology Chinese Academy of Sciences Shijiazhuang 050021 （China）

This paper addresses the emergence of water security problems in North china with the aim of highlighting key waterresources management and water security issues for the long-term development of North china. Three key problemsrelated to water resources and security issues in North china in the 21st century are addressed, namely 1) the watercycle under environmental change, 2) agricultural water saving, and 3) water security. Development of internationalresearch related to these issues is also reviewed. The research plan developed recently by the Chinese Academy of Sciences(CAS) is discussed and suggestions on research and development of water resources science in North china are *** to focus on experimental catchments and dedicated research stations, a detailed knowledge of the water cycle onNorth china farmland has been compiled. A range of techniques that include isotope tracers has been used to acquirehydrologic data. Much research has been devoted to developing distributed hydrological models at different scales. In thewell irrigation district, five different water saving irrigation regimes have been investigated, and these regimes have hadwidespread application, and reduced water use 60-150 mm while they increased water use efficiency (WUE) by 20%-30%.Furthermore, preventing water pollution is the most essential step to ensure North china’s water security.

关键词： environmental change North china water cycle water resources water security

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Hydrogen isotopic compositions, distributions and source signals of individual n-alkanes for some typical crude oils in Lunnan Oilfield, Tarim Basin, NW china

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Science china Earth Sciences 2005年第8期48卷 1220-1226页

作者： LU Hong1, LI Chao1, SUN Yongge1, PENG Ping’an1 & XIAO Zhongyao2 1. State key laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou510640, china 2. Tarim Research Institute of Exploration and Development of Petroleum, china Petroleum, Korla 841000, china 1. State key laboratory of Organic Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences 510640 Guangzhou China 2. Tarim Research Institute of Exploration and Development of Petroleum China Petroleum 841000 Korla China

Isotopic compositions of carbon-bound hydrogen in individual n-alkanes from sev-eral typical crude oil samples from Lunnan Oilfield, Tarim Basin, NW china, were firstly measured using newly developed gas chromatography-thermal conversion-isotope ratio mass spectrometry. The similar range of δ D of individual n-alkanes of crude oils among reservoirs of different geo-logical times reflects that hydrocarbons are all derived from the same marine depositional envi-ronment. Compared to the theoretic value (?150‰) and the reported δ D values (nC13―nC27, ?160‰―?90‰) of individual n-alkanes for Ordovician-sourced crude oils in the Canadian Wil-liston Basin, the hydrogen isotopic composition of individual n-alkanes in crude oils from Lunnan Oilfield is characterized by heavy hydrogen isotopic values (nC12―nC27, ?120‰―?60‰). In terms of the factors that control the fractionation of hydrogen isotopes, relatively saline deposi-tional environment and higher thermal maturation were attributed to the heavy δ D values of in-dividual n-alkanes in crude oils from Lunnan Oilfield.

关键词： hydrogen isotopes, individual n-alkanes, distribution, hydrocarbon source, Lunnan Oilfield.

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REE and Sr-Nd isotope characteristics of hydrothermal chimney at Jade area in the Okinawa Trough

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Acta Oceanologica Sinica 2004年第2期23卷 287-296页

作者： LIUYanguang MENGXianwei FUYunxia keylaboratoryofMarineSedimentologyandEnvironmentgeologyofStateOceanicAdministration Qingdao266061China GeologicalResourceandGeotechnicalEngineeringCooperationofQingdao Qingdao266071China

Hydrothermal chimney is a product of hydrothermal activity on the seabed. Chimney samples dredged from Jade hydrothermal area in Izena depression of the Okinawa Trough, are characterized by relatively enriched light rare earth elements (LREE) and strongly positive Eu anomalies. 87Sr/86Sr and 143Nd/144Nd of these samples are exactly between those of seawater and of acidic pumice, averaged at 0.708928 and 0.512292, respectively. These characteristics imply that the main source of hydrothermal sulfide at Jade area is possibly the undersurface acidic rocks. The mineralizing mechanism can be summarized as follows: Large amount of mineralized material would be leached out and LREE-enriched hydrothermal solution would be subsequently produced as a result of thermo-chemical exchange reaction between acidic volcanic rocks and heated seawater that penetrated in advance from upper water mass. The spurting out from the seabed and quickly crystallizing in the seawater of hydrothermal solution are responsible for the formation of Cu-Zn sulfide and barite-amorphous SiO2 minerals that are characterized by enriched LREE and positively strong Eu anomalies.

关键词： hydrothermal chimney rare earth elements Sr and Nd isotopes

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Biocompatibility evaluation in vitro. Part II: Functional expression of human and animal osteoblasts on the biomaterials

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Journal of Central South University of Technology 2001年第2期8卷 75-82页

作者： RUAN Jian ming 1,GRANT M. Helen 2 (1.State key laboratory for Powder Metallurgy, Central South University, Changsha 410083, china 2.Bioengineering Unit, Strathclyde University, Glasgow, G4 0NW, UK) 1. State key laboratory for Powder Metallurgy Central South University 410083 Changsha China 2. Bioengineering Unit Strathclyde University G4 0NW Glasgow UK

DNA synthesis and collagen formations on the implant material by cell culture in vitro are the most important phenotypical expression to estimate the biocompatibility. In this part, DNA synthesis and collagen formation on implant materials were quantitatively and qualitatively estimated by radioactive isotope H + thymidine to incorporate into DNA chains, H + proline to incorporate into type I collagen proteins followed by scin tillation counting and antibody antigen immunocytochemistry staining, respectively. Research results demonstrate that hydroxyapatite (HA) stimulates DNA synthesis and collagen formation on the material whereas this stimulation is restricted by adding spinel to the materials. There are statistical differences between the influences of material components on both DNA synthesis and collagen formation. It is supposed that porous materials can supply more platforms for cell anchoring, and more DNA and collagen are synthesised on the porous materials. Immersion in culture medium results in new HA crystal formation on the porous HA materials.

关键词： biocompatibility DNA synthesis collagen protein incorporation

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Temperature-induced fractionation of oxygen isotopes of diatom frustules and growth water in Lake Sihailongwan in Northeast china

Temperature-induced fractionation of oxygen isotopes of diat...

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中国科学院地质与地球物理研究所第十届(2010年度)学术年会

作者： LI Dong & HAN JingTai~* key laboratory of Cenozoic geology and Environment,Institute of geology and Geophysics,Chinese Academy of Sciences,beijing 100029, china

Diatom oxygen isotopes have been widely applied in quantitative reconstruction of the paleoclimate and paleoenvironment,but have rarely been reported in *** the present study,Lake Sihailongwan in Northeast china was selected for detailed investigation of oxygen isotopic fractionation between diatom frustules and lake water induced by growth *** study involved a 2-year period of field monitoring of the lake water temperature at multiple depths and biweekly collections of traps for both sediment and water at shallow and bottom depths(7 and 49 m below the lake surface,respectively),diatom separation and purification of the trap sediments,and oxygen isotope measurement for diatom silica and lake water *** conditioned experiment conducted herein demonstrated that the laboratory device,methods and techniques used in this study were capable of generating reliable data for the typical oxygen isotope composition of diatom *** data obtained revealed a prominent linear relationship between the oxygen isotope composition of the modern diatom and lake temperature during *** fractionation coefficient was about -0.185‰/℃-0.238‰/℃in the temperature range of 3.6-24℃,which is consistent with the observations from various aquatic environments and laboratory culture with different diatom *** findings provide strong support for the dominant control of the growth temperature on the oxygen isotope fractionation between the diatom frustules and ambient water.A notable difference in the fractionation coefficient was observed between the surface and bottom diatom oxygen isotopes,suggesting that various depositional processes and taphonomic effects influenced the surface and bottom trap samples. Another factor leading to this difference may be that enrichment by evaporation and dilution by rainfall have a stronger influence on the ***,the results presented here demonstrate significant progress in evaluation of diatom oxygen isotope

关键词： diatom silica oxygen isotope isotopic fractionation Lake Sihailongwan Northeast china

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The δ^(18)O variation of a stalagmite from Qixing Cave,Guizhou Province and indi-cated climate change during the Holocene

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Chinese Science Bulletin 2001年第22期46卷 1904-1908页

作者： CAI Yanjun, ZHANG Meiliang, PENG Zicheng, LIN Yushi, AN Zhisheng, ZHANG Zhaofeng & CAO YunningState key laboratory of Loess and Quaternary geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi’an 710054, china Karst Dynamics laboratory, Ministry of Land and Resources, Guilin 541003, china Department of Earth and Space Science, University of Science & Technology of china, Hefei 230023, china State key laboratory of Loess and Quaternary geology Institute of Earth Environment Chinese Academy of Sciences Xi’an China Karst Dynamics laboratory Ministry of Land and Resources Guilin China Department of Earth and Space Science University of Science & Technology of China Hefei China

A stalagmite from Qixing Cave, Guizhou Province was dated with the TIMS U-series method and its oxygen isotope composition was analyzed. On the basis of the ages and the variations of the δ18O of the stalagmite, the climate change of the last 7.7 ka has been reconstructed in this area: 7.7-5.8 ka, summer monsoon maximum period; 5.8-3.8 ka summer monsoon weakening period; 3.8-0.15 ka, weakened summer monsoon and high amplitude climate fluctuations period. We put forward that the increasing trend of δ18O of the stalagmite reflected not only the weakening of the summer monsoon, which was caused by the decreasing of solar radiation in the Northern Hemisphere, but also the possibly decreasing contribution of the southwest monsoon to the rainfall of this area. These results are consistent with the output of the numerical climate-model modeling. The high amplitude fluctuation of the δ18O may imply the quick shift of the contributions of different moisture sources to the precipitation in this area.

关键词： stalagmite Holocene southwest monsoon.

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