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Isotopic evolution of the terminal Neoproterozoic and early Cambrian carbon cycle on the northern Yangtze Platform, South china

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Progress in Natural Science:Materials International 2003年第12期 62-65页

作者： GUO Qingjun 1,2. *, LIU Congqiang 1, Harald STRAUSS 3.and Tatiana GOLDBERG 3.1. Institute of Geochemistry, {2. academy of Sciences, Guiyang 550002. china 2. Graduate School, {2. academy of Science, beijing 100018, china 3. Geologisch Palontologisches Institut, Westflische Wilhelms Universitt Münster, 48148 Münster, Germany) Institute of Geochemistry，chinese academy of Sciences，Guiyang 550002.{2. Graduate School，chinese academy of Science，{2. 100018，{3. Institute of Geochemistry，chinese academy of Sciences，Guiyang 550002.{2. Geologisch-Palaontologisches Institut，Westfalische Wilhelms-Universitat Münster，48148 Münster，Germany

Profound geotectonic, climatic and biological changes occur during the terminal Neoproterozoic and its transition into the early Cambrian. These are reflected in temporal variations of the chemical and isotopic composition of seawater. We are studying a sequence of sedimentary rocks at the Shatan section, northern Yangtze Platform, Sichuan Province of china. This succession comprises, in ascending stratigraphic order, predominantly calcareous sediments of the Sinian upper Dengying Formation and black shales of the lower Cambrian Guojiaba Formation (time equivalent of Niutitang Fm.). Paleoenvironmental setting represents shallow water shelf deposits. The objective of our study is to provide temporal records for the isotopic compositions of organic and carbonate carbon throughout this time interval. Organic carbon isotope values display a range between -{2..8‰ and -{2..1‰ with clear stratigraphic variations. Carbonate carbon isotope data vary between -{2.5‰ and +0.5‰. These secular variations are interpreted to reflect perturbations of the global carbon cycle, specifically changes in the fractional burial of organic carbon. However, local conditions have further affected the isotopic signals.

关键词： terminal Neoproterozoic Early Cambrian carbonate and organic carbon isotopic composition Yangtze Platform Shatan section.

Dinosaur eggs and dinosaur egg-bearing deposits(Upper Cretaceous) of Henan Province,china:Occurrences,palaeoenvironments,taphonomy and preservation

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Progress in Natural Science:Materials International 2009年第11期19卷 1587-1601页

作者： Xinquan Liang~(a,*),Shunv Wen~(a,b),Dongsheng Yang~a,Shiquan Zhou~c,Shichong Wu~d a Key laboratory of isotope Geochronology and Geochemistry,Guangzhou Institute of Geochemistry,{2. {3. of Sciences, Guangzhou 510640,china b Graduate School of the {2. {3. of Sciences,beijing 10003.,china c First Geology and Exploration Institute,Henan Bureau of Geology,Mineral Exploration and Development Supervision,Nanyang 473.03.china d Zhuzhou Institute of Mineral Resources and Geological Survey,Hunan Geological Survey,Zhuzhou 412.07,china [a]Key laboratory of isotope Geochronology and Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China [b]Graduate School of the chinese academy of Sciences Beijing 100039 China [c]First Geology and Exploration Institute Henan Bureau of Geology Mineral Exploration and Development Supervision Nanyang 473003 China [d]Zhuzhou Institute of Mineral Resources and Geological Survey Hunan Geological Survey Zhuzhou 412007 China

The Upper Cretaceous dinosaur egg-bearing deposits in Henan Province,central china are divided into three formations in ascending order:Gaogou,Majiacun and *** Gaogou Formation belongs to alluvial fan deposits containing the fossil dinosaur egg assemblage of Faveoloolithus,Dendroolithus,Dictyoolithus,Paraspheroolithus and *** Majiacun Formation is interpreted as braided stream to meandering stream deposits with assemblage of Ovaloolithus,Paraspheroolithus,Placoolithus,Dendroolithus,Prismatoolithus, rare Youngoolithus and *** Sigou Formation is shallow lacustrine/palustrine to low-sinuosity river sedimentary rocks with assemblage of Macroolithus,Elongatoolithus,Ovaloolithus and Paraspheroolithus. To date,3. oospecies,13.oogenera and 8 oofamilies of dinosaur eggs have been *** dinosaur eggs are preserved in the floodplain deposits,whereas allochthonous and parautochthonous dinosaur eggs are preserved in the alluvial *** suggests that river floodplains are the best environments for the preservation of numerous autochthonous dinosaur *** preservation of most dinosaur eggs in brown to red calcic palaeosoils,muddy siltstones or mudstones suggests that the paleoclimate of the nesting area was *** presence of gray and green mudstone and coal layers,however,indicates that there existed an ephemeral subhumid climate during the middle and Late *** is suggested that such a climate was favorable for the development of meandering streams in a vegetated environment.

关键词： Dinosaur eggs Upper Cretaceous Fluvial deposit Characteristics of taphonomy and preservation Henan Central china

Single grain Rb-Sr isotopic analysis of GA-1550 biotite,LP-6 biotite and Bern-4M muscovite 40Ar-3.Ar dating standards

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Single grain Rb-Sr isotopic analysis of GA-1550 biotite,LP-6...

Tectono-chronologic constraints on a Mesozoic slip and thrust belt in the eastern Jiaodong Peninsula

中国科学院地质与地球物理研究所2.08学术年会

作者： QIU-LI LI,~(1,2. FUKUN CHEN,~(2.3.) XIANG-HUI LI,~(2.3. FEI WANG~3.and HUAI-YU HE~3.1 Key laboratory of Mineral Resources,Institute of Geology and Geophysics,chinese academy of Sciences, {3. 10002.,china 2.laboratory for Radiogenic isotope Geochemistry,Institute of Geology and Geophysics,chinese academy of Sciences, {3. 10002.,china 3.State Key laboratory of Lithospheric Evolution,Institute of Geology and Geophysics,chinese academy of Sciences, {3. 10002.,china

Three standard minerals GA-1550 biotite,LP-6 biotite and Bern-4M muscovite used for K-Ar and Ar-Ar dating have been investigated by the single grain Rb-Sr *** to the K-Ar and Ar-Ar results previously reported,these mica standards nevertheless show complex characteristics in the Rb-Sr isotopic *** on eight individual grains of GA-1550 biotite gives a Rb-Sr isochron age of 98.7±1.9 Ma,consistent with previous dating results of the K-Ar and stepwise heating and laser ablation Ar-Ar *** evidence of the laser ablation Ar-Ar analyses in many previous studies demonstrates that LP-6 biotite is considerably inhomogeneous in the K-Ar isotopic system,Rb-Sr isotopic analyses on ten individual biotite grains show achievement of Sr isotopic equilibrium during crystallization.A Rb-Sr isochron age of 12..2.2.2.Ma calculated from the analytical results is concordant with those previously reported K-Ar and Ar-Ar ages obtained from c.3. mg aliquots of biotite *** age reproducibility on Bern-4M muscovite was previously achieved by K-Ar and Ar-Ar dating by total fusion in c.3. mg aliquots of muscovite grains,but single grain Rb-Sr analytical results in this study demonstrate considerable disequilibrium of Sr isotopic system during crystallization of *** discordance in the Rb-Sr and K-Ar isotopic systems of two standard minerals indicates complex factors that can influence isotopic disequilibrium of both isotopic systems.

关键词： Rb-Sr isotopic systematics standard mica GA-1550 biotite LP-6 biotite Bern-4M muscovite

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Science china Earth Sciences 2007年第1期50卷 25-32页

作者： ZHANG HongYuan1,2. HOU QuanLin3.& CAO DaiYong 4 1 Institute of Geology, chinese {2. of Geological Sciences, beijing 100037,{3. 2.State Key laboratory of Geological Processes and Mineral Resources,{3. University of Geosciences, beijing 100083.{3. 3.Graduate School of{3. Acacemy of Sciences, beijing 10003.,{3. 4 Key laboratory of Coal Resources (CUMT), Ministry of Education, beijing 100083.{3. 1. Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China 2. State Key laboratory of Geological Processes and Mineral Resources China University of Geosciences Beijing 100083 China 3. Graduate School of china {2. of Sciences Beijing 100039 China 4. Key laboratory of Coal Resources (CUMT) Ministry of Education Beijing 100083 China

A major slip and thrust belt within the eastern Jiaodong Peninsula is located at the eastern terminal of the Qinling-Dabie-Sulu orogenic belt between the Sino-Korea Block and Yangtze Block. Although a lot of isotope chronologic data have been obtained regionally, little structural chronological research has been conducted in this region and this paper corrects that. Syn-deformational minerals were system-atically selected from samples of the NE-ENE trending transpressional shear zones and transpres-sional nappes and carefully analysed using 40Ar/3.Ar methods. Two tectonic events were defined with the first event resulting from early movement of transpressional nappes around 190 Ma ago. This ac-cords with the period of syn-orogenic sinistral slip of the Tan-Lu faults and clockwise shear in the Eastern Qinling-Tongbaishan part of the Qinling-Dabie-Sulu orogenic belt. The second event involved strikeslip thrust movement of deep shear zones between 13.Ma and 12.Ma. This resulted from the onset of Mesozoic tectonic conversion in the eastern Jiaodong Peninsula. The sinistral strikeslip-thrusting in Jiaodong Peninsula and the extensional tectonism (toward ESE) in Liaodong Peninsula probably resulted in the clockwise rotation of Korea Peninsula in late Mesozoic.

关键词： the eastern Jiaodong Peninsula tectono-chronology 40Ar/3.Ar strikeslip and thrust belt.

Biogas charging and dissipating process and its accumulation in the Sebei gasfield,Qaidam Basin,china

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Science china Earth Sciences 2008年第S1期51卷 36-44页

作者： JIN Qiang 1,CHENG FuQi 1,2.,SU AiGuo 3.,ZHU GuangYou 3.,WANG Li 1 &CAO Qian 1 1{2. University of Petroleum,Dongying,Shandong 2.7061,china 2.Geological Institute of Shengli Oilfield,SINOPEC,Dongying,Shandong 2.7015,china 3.Petroleum Exploration and Development Institute,Petrochina,beijing 100083.china china Univ Petr Shandong 257061 Peoples R China SINOPEC Geol Inst Shengli Oilfield Shandong 257015 Peoples R China Petrochina Petr Explorat & Dev Inst Beijing 100083 Peoples R China

The Sebei gasfield is the largest biogas accumulation found in china and many reservoirs and seal rocks superposed on a syndepositional anticline in *** biogas charging and dissipating process and its distribution have been a research focus for many *** authors suggest a diffusing and accumulating model for the biogas,as they find that the shallower the gas producer,the more methane in the biogas,and the lighter stable carbon isotope composition of *** on the diffusing model,diffused biogas is quantitatively estimated for each potential sandy reservoir in the gasfield,and the gas charging quantity for the sandy reservoir is also calculated by the diffused gas quantity plus gas reserve in-place.A ratio of diffusing quantity to charging quantity is postulated to describe biogas accumulating state in a sandy reservoir,if the ratio is less than 0.6,the reservoir forms a good gas-pool and high-production layer in the gasfield,which often occurs in the reservoirs deeper than 900 m;if the ratio is greater than 0.6,a few gas accumulated in the reservoir,which frequently exists in the reservoirs shallower than 900 ***,a biogas accumulation model is built up as lateral direct charging from gas source for the sands deeper than 900 m and indirect charging from lower gas-bearing sands by diffusion at depth shallower than 900 *** this charging and diffusion quantitative model,the authors conducted re-evaluation on each wildcat in the central area of the Qaidam Basin,and found many commercial biogas layers.

关键词： biogas charging and diffusing model relative dissipated quantity Qaidam Basin

An Experimental Calibration on the Sphalerite-Galena Sulfur isotope Geothermometer

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Acta Geologica Sinica(English Edition) 2003年第4期77卷 519-521页

作者： DING Tiping, ZHANG Chengxin, WAN Defang, LIU Zhijian and ZHANG Guilan Institute of Mineral Resources, chinese academy of Geological Sciences, 2. Baiwanzhuang Rd.,{2. {3. Institute of Mineral Resources Chinese Academy of Geological Sciences 26 Baiwanzhuang Rd. Beijing 100037

A new experimental calibration was undertaken in this study to get a more reliable sphalerite-galena sulfur isotope geothermometer. The experimental conditions selected in study were very similar to those of natural hydrothermal solution. The high-precision SF6 method was used in sulfur isotope analyses. The obtained calibration curve for sulfur isotope fractionation between sphalerite and galena can be expressed with the equation 10001nαSp-Gn= 0.74×106T-2.0.08.

关键词： sulfur isotopes isotope geothermometer SF6 method sphalerite galena

Multiphase tectonic movements, cap formations and evolution of the Majiang paleo-reservoir

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Petroleum Science 2011年第2期8卷 127-133页

作者： Tang Liangjie Cui Min State Key laboratory of Petroleum Resources and Prospecting China University of Petroleum Beijing 102249 China CNOOC Research Institute Beijing 100027 China

The Majiang paleo-reservoir is a typical destroyed hydrocarbon reservoir, buried in carbonate strata of china＇s southern marine-facies. Field geological explorations, interpretations of seismic profiles and balanced cross-section restorations around this paleo-reservoir reveal that its formation and evolution have been restricted by multiphase tectonic movements of different intensities. A regional tectonic mechanism and model have been suggested for the formation and evolution of the Majiang paleo- reservoir. Geological field exploration has been carried out along three typical Silurian cross-sections and rock samples were tested in combination with water-rock interaction. Based on the result of cap tests, the planar distribution, the residual thickness, the erosion thickness and the preservation conditions, the Silurian mudstone cap is discussed around the Majiang paleo-reservoir. Combining the hydrodynamic conditions of its formation and evolution and its tectonic movements, we determined the fact that the thicker the cap is, the more resistant it is to hydrodynamic destruction. The multi-phase formation and destructive geological model of the paleo-reservoir is established through an overall analysis of multi- phase tectonic evolutions, cap developments, hydrodynamic conditions and solid mineral metallogenic ages measured by Rb-Sr, Pb and Sm-Nd isotope techniques.

关键词： Multiphase tectonic evolution key tectonic changes cap evolution hydrocarbonpreservation Majiang paleo-reservoir

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 2.402., china 2.Key {2. of Plant-Soil Interactions, Ministry of Education, College of Resources and Environmental Sciences, china Agri- cultural University, {3. 100193. china 3.Institute of Geology and Geophysics, chinese academy of Sciences, {3. 10002., china 4 College of Environmental Sciences, MOE {2. for Earth Surface Processes, Peking University, {3. 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 13.) 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 13. 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 13. for C3.plants is about 1.3. per kilometer. Temperature determines the altitudinal trend of δ 13..

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

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Natural gas geochemistry and its origins in Kuqa depression

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Science china Earth Sciences 2008年第S1期51卷 174-182页

作者： LIU QuanYou 1 ,QIN ShengFei 1 ,LI Jian 2.,LIU WenHui 3.,ZHANG DianWei 3.,ZHOU QingHua 1 &HU AnPing 1 1 Research Institute of Petroleum Exploration and Development,Petro{2.,beijing 100083.{2. 2.Langfang Branch of Research Institute of Petroleum Exploration and Development,Petro{2.,Langfang 065007,{2. 3.Exploration and Production Research Institute,SINOPEC,beijing 100083.{2. Petrochina Res Inst Petr Explorat & Dev Beijing 100083 Peoples R China Petrochina Langfang Branch Res Inst Petr Explorat & Dev Langfang 065007 Peoples R China SINOPEC Explorat & Prod Res Inst Beijing 100083 Peoples R China

According to gas compositional and carbon isotopic measurement of 114 gas samples from the Kuqa depression,accumulation of the natural gases in the depression is dominated by hydrocarbon gases, with high gas dryness(C1/C1-4)at the middle and northern parts of the depression and low one towards east and west sides and southern *** carbon isotopes of methane and its homologues are relatively enriched in 13.C,and the distributive range ofδ13. 1 ,δ13. 2.andδ13. 3.is-3.‰―-3.‰,-2.‰―-2.‰and-2.‰―-2.‰,*** general,the carbon isotopes of gaseous alkanes become less negative with the increase of carbon ***δ13. CO2.value is less than-10‰in the Kuqa depression,indicating its organogenic *** distributive range of 3.He/ 4 He ratio is within n×10-8 and a decrease in 3.He/ 4 He ratio from north to south in the depression is *** on the geochemical parameters of natural gas above,natural gas in the Kuqa depression is of characteristics of coal-type gas *** possible reasons for the partial reversal of stable carbon isotopes of gaseous alkanes involve the mixing of gases from one common source rock with different thermal maturity or from two separated source rock intervals of similar kerogen type,multistages accumulation of natural gas under high-temperature and over-pressure conditions,and sufficiency and diffusion of natural gas.

关键词： Kuqa depression natural gas stable carbon isotope gas origin