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Progress and review of the studies on the end-Triassic mass extinction event

Science china Earth Sciences 2005年第12期48卷 2049-2060页

作者： DENG Shenghui1,2. LU Yuanzheng1,2.3 & XU Daoyi4.1. Research Institute of Petroleum exploration and Development,{2. 2. Key Laboratory of Oil and Gas Reservoir of Petrochina,{2. 3. china university of geosciences,{2. 4. Institute of geology, china Earthquake Administration, {12. 10002., china Research Institute of Petroleum exploration and Development Beijing China Key Laboratory of Oil and Gas Reservoir of Petrochina Beijing China china university of {2.sciences Beijing China Institute of geology China Earthquake Administration Beijing China

The mass extinction at the end-Triassic is one of the five biggest in the Phanerozoic. However,it is the least well understood among these five events, and only till last decade it became a great academic interesting subject to geologists. The evidences for this event come obviously from bivalves, brachiopods, ammonites, corals, radiolaria, ostracods and foraminifera of marine habitats, and plants and tetrapods of terrestrial realm. By contrast, for some of other groups, such as marine gastropods and marine vertebrates, no mass extinction has been recog-nized yet. The extinction event is strongly marked at specific level but shown a complicated situa-tion at generic and family levels. Dramatic changing of the environment, such as the temperature raise due to the greenhouse effect, the marine anoxic habitats caused by a sudden transgression after the regression at the end of Triassic, has been claimed to be the main cause of the extinction. Many hypotheses have been suggested to demonstrate the mechanisms of the environment changing, among which two popular ones are the bolide impact and volcanic eruption. The Triassic-Jurassic (Tr-J) boundary mass extinction event is still poorly understood because no enough data have been obtained from the Tr-J boundary successional sections of both marine and terrestrial sediments, and most of these studies were regionally restricted. The basic aspects of the event and its associated environmental conditions remain poorly characterized and the causal mechanism or mechanisms are equivocal. Some authors even doubt its occurrence. china has many successionally developed terrestrial and marine Tr-J sections. Detailed studies of these sections may be important and significant for well understanding of the event.

关键词： progress, review, end-Triassic, mass extinction, mechanism, Tr-J boundary.

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The crustal structure under Sanjiang and its dynamic implications:Revealed by seismic reflection/refraction profile between Zhefang and Binchuan,Yunnan

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Science china Earth Sciences 2005年第9期48卷 1329-1336页

作者： ZHANG Zhongjie1, BAI Zhiming1, WANG Chunyong2. TENG Jiwen1, Lü Qingtian3, LI Jiliang1, LIU Yifeng1 & LIU Zhenkuan4.1. Institute of geology and geophysics, Chinese Academy of Sciences, beijing 10002., china 2. Institute of geophysics, china Seismological Bureau, beijing 100085, china 3. Institute of Deposition Resource, Chinese Academy of geosciences, beijing 100037, china {12., china university of geosciences, beijing 100083. china Institute of geology and geophysics Chinese Academy of Sciences Beijing China Institute of geophysics China Seismological Bureau Beijing China Institute of Deposition Resource Chinese Academy of Geosciences Beijing China school of exploration and {2. China University of Geosciences Beijing China

The fault belts in Sanjiang mainly include Jinshajiang-Honghe fault, Lancangjiang fault and Nujiang fault (called Sanjiang faults) in western Yunnan Province, china. By interpreting the wide-angle seismic reflection/refraction profile between Zhefang and Binchuan, which crosses Tengchong and Baoshan blocks in Dianxi (western Yunnan) tectonic zone, we recon- struct the crustal structure with seismic traveltime tomography for crustal P-wave velocity and the seismic scattering image for crustal seismic reflection structure. In this paper, we firstly present the crustal structure images of P-wave velocity and seismic reflection under the wide-angle seismic profile. These results demonstrate that, the crustal velocity structure and seismic reflec- tion structure along the profile can be divided into 3 segments, and there is an obvious difference of crustal structure among the eastern, the western and the middle segment. Generally, crustal P-wave velocities in the Baoshan segment are 0.1―0.2.km/s slower and seismic reflection am- plitudes from Moho discontinuity are stronger than the other 2.segments. In the studied area, crustal thickness is about 4. km, and shows the thickening tendency from west to east along the profile. Additionally, it can be seen that there is one strong-amplitude seismic reflection event as bright points at the depths of 8―10 km, along the segment of 80―115 km of the profile (south- ward of Tengchong); and seismic reflection wave-field from Moho discontinuity varies obviously along the lateral direction. Finally, we make some discussions on the crustal thickening pattern in the Sanjiang fault belt, structural environment of earthquake development and the contact rela- tionship between the Tengchong block, Banshan block and Luxi trough.

关键词： Sanjiang area wide-angle seismic profile crustal structure.

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Transport network and flow mechanism of shallow ore-bearing magma in Tongling ore cluster area

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Science china Earth Sciences 2006年第4期49卷 397-407页

作者： DENG Jun1,2. WANG Qingfei1,2., HUANG Dinghua3 , WAN Li4. YANG Liqiang1,2.& GAO Bangfei1,2.1. State Key Laboratory of geological Processes and Mineral Resources, {2. university of geosciences,{4. 2. Key Laboratory of Lithosphere Tectonics and Lithoprobing Technology of Ministry of Education, {2. university of geo- sciences,{4. 3. Faculty of Earth Sciences, {2. university of geosciences, Wuhan 4.0074. {2. 4. school of Mathematics and {14. Science, Guangzhou university, Guangzhou 5104.5, {2. State Key Laboratory of geological Processes and Mineral Resources China University of Geosciences Beijing China Key Laboratory of Lithosphere Tectonics and Lithoprobing Technology of Ministry of Education China University of Geosciences Beijing China Faculty of Earth Sciences China University of Geosciences Wuhan China school of Mathematics and information Science Guangzhou University Guangzhou China

Abundant studies revealed that shallow intrusions of the Yanshanian epoch resulted in the mass mineralization of the Tongling region. Various evidences showed there existed a concealed magma chamber at ?10 km depth in the middle part of this region during Yanshanian epoch, from which the ore-forming magma was generated and then transported to the superficial layer. Yet the transport network and flow mechanism of the shallow ore-bearing magma, the key problem associ- ated with ore-forming process, was relatively little focused on. Integrate analysis of structural me- chanics, statistical fractal and geological facts suggested that NE trending high-angle fold-related thrust faults and the tessellated basement ones served as the main pathways for the shallow magma’s transporting, moreover, the saddle void spaces among adjacent strata in the folds upon this fault system provided the place for magma’s emplacement. So the folds in the upper part and faults in the lower part of the upper crust constituted the fluid’s transport and emplacement network. During the deformation of geologic body with multi-layer structure, the layers in the upper part tended to fold when received the jacking stress from the lower part, while the lower one inclined to fault undergoing loads of the upper part. And the producing probability of this structure assemblage was highly in- creased in the condition, such as in the Tongling area, that the mechanic rigidity of the lower layers was stronger than that of the upper ones. For the pre-existence of fluid-conducting network, the top magma with high volatile in the magma chamber transported rapidly to the superficial layer in dyking pattern, located in the void spaces of folds, filled and reconstructed them. The sudden drop of pres- sure caused the fluid unmixing from the magma and mass ore-forming elements concentration. Pulse activity of the dyking may be the principal reason why magmatic bodies in the Tongling area were spatially-temporally con

关键词： Tongling, structural network, magma intrusion, fractal, dyke.

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Study on NDVI-T_s space by combining LAI and evapotranspiration

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Science china Earth Sciences 2006年第7期49卷 747-754页

作者： HAN Lijuan1,2.3, WANG Pengxin4. YANG Hua1,2.3, LIU Shaomin1,2.3 & WANG Jindi1,2.3 1. Research Center for Remote Sensing and GIS, school of {2.graphy, beijing Normal university, beijing 100875, china 2. State Key Laboratory of Remote Sensing Science, beijing 100875, china 3. beijing Key Laboratory for Remote Sensing of Environment and Digital Cities, beijing 100875, china 4. Department of information Management, College of information and Electronic Engineering, china Agricultural university, beijing 100083. china Research Center for Remote Sensing and GIS School of Geography Beijing Normal University Beijing China State Key Laboratory of Remote Sensing Science Beijing China beijing Key Laboratory for Remote Sensing of Environment and Digital Cities Beijing China Department of information Management College of Information and Electronic Engineering China Agricultural University Beijing China

This paper focuses on interpreting the different spatial relationships between NDVI and Ts, a triangular or a trapezoid, and on analyzing transformation conditions, the physical and ecological meanings of the vegetation index-surface temperature space as well. Further, we use the Tempera-ture-Vegetation Dryness Index (TVDI) to explain the existent meaning of a triangular space after NDVI reaches its saturated state by employing the relationships between NDVI, LAI and evapotranspiration. The specific relations between NDVI and Ts are useful for describing, validating and updating land surface models.

关键词： NDVI, land surface temperature, evapotranspiration, leave area index.

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Application of backflush and micro-flow techniques to the analysis of C5—C13 hydrocarbons in crude oils and its geochemical significance

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Progress in Natural Science:Materials International 2007年第11期17卷 1382-1387页

作者： Wang Peirong1,2. Zhao Hong2.3, Xu Guanjun1,4. Zhu Cuishan2.3, Xiao Tingrong4. Zhang Min2.3 and Zhang Bin1,4.1. Key Laboratory of Petroleum geochemistry, china National Petroleum Corporation, beijing 100083. china 2. geochemistry Department of Yangtze {4., Jingzhou 4.4.2., china 3. Key Laboratory of exploration Technologies for Oil and Gas Resources, Ministry of Education, Yangtze {4., Jingzhou 4.4.2., china 4. Petroleum geology Central Laboratory, Research Institute of Petroleum exploration and Development, Petrochina, beijing 100083. china) Key Laboratory of Petroleum geochemistry China National Petroleum Corporation Beijing 100083 China geochemistry Department Yangtze University Jingzhou 434023 China Key Laboratory of exploration Technologies for Oil and Gas Resources Yangtze University Jingzhou 434023 China Petroleum geology Central Laboratory Research Institute of Petroleum Exploration and Development PetroChina Beijing 100083 China

An Agilent 6890N GC equipped with both FID and Agilent 5975 MSD analyzer has been employed to analyze C5—C13 hydrocarbon fractions of crude oils. A technical combination of program temperature volatilizer injection, backflush and micro-flow controller afforded a fine separation of C5—C13 compounds on a PONA column with the heavy part of crude oils being cut off before entering the analytical column. Both GC-FID chromatogram and GC-MS mass chromatograms (MID and full scan) could be obtained at the same time. The retension time differences of nC6—nC13 alkanes between GC and TIC were in the range of 0.02.0.58 minutes. Totally 2.6 peaks have been assigned group compositions. Results on 8 typical oil samples from CNPC Key Laboratory Crude Oil Library showed that the characteristics of C6—C13 hydrocarbon group composition could be used in oil-oil correlation studies.

关键词： GC analysis GC/MS analysis backflush micro-flow controller light fraction in crude oil

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Effects of abnormally high heat stress on petroleum in reservoir——An example from the Tazhong 18 Well in the Tarim Basin

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Science china Earth Sciences 2008年第4期51卷 515-527页

作者： ZHU DongYa1, JIN ZhiJun1, HU WenXuan2.& ZHANG XueFeng3 1 Petroleum exploration and Production Institute, china Petroleum & Chemical Corporation,{2. 2.Department of Earth Sciences, Nanjing university, Nanjing 2.0093, china 3 school of Resource and information, china university of Petroleum, beijing 102.4., china Petroleum exploration and Production Institute China Petroleum & Chemical Corporation Beijing China Department of Earth Sciences Nanjing University Nanjing China school of Resource and information China University of Petroleum Beijing China

An igneous intrusion of 94. thick was discovered intruding into the Silurian sandstone from Tazhong 18 Well. The petroleum previously preserved in the Silurian sandstone reservoir was altered into black carbonaceous bitumen by abnormally high heat stress induced by the igneous intrusion. The reflec-tance of the carbonaceous bitumen reaches as high as 3.54., indicating that the bitumen had evolved into a high thermal evolution level. Similar to the Silurian samples from the neighboring Tazhong 11, Tazhong 12. Tazhong 4. and Tazhong 4. wells, the distribution of C2., C2. and C2. steranes of the car-bonaceous bitumen is still "V" -shaped and can still be employed as an efficient parameter in oil source correlation. The "V" -shaped distribution indicates that the hydrocarbons from the Tazhong 18 and the neighboring wells were all generated from the Middle-Upper Ordovician hydrocarbon source rocks. However, the oil source correlation parameters associated with and terpanes had been changed greatly by the high heat stress and can no longer be used in oil source correlation. The δ 13C values of the pe-troleum from the neighboring wells are between -32.53‰ and -33.37‰, coincident with those of the Paleozoic marine petroleum in the Tarim Basin. However, the δ 13C values of the carbonaceous bitumen from the Tazhong 18 Well are between -2..18‰ and -2..2.‰, isotopically much heavier than the pe-troleum from the neighboring wells. The content of light hydrocarbons (nC14.nC2.) of the saturated hydrocarbon fraction in the carbonaceous bitumen is extremely higher than the content of heavy hy-drocarbons. The light/heavy hydrocarbon ratios (ΣnC2.-/ΣnC2.+) are between 4.56 and 39.17. In the saturated fraction, the even numbered hydrocarbons are predominant to the odd numbered, and the OEP (Odd to Even Predominance) values are between 0.2. and 0.4.. However, the content of light hy-drocarbons in the petroleum from the neighboring wells is relatively low and the content of the even numb

关键词： Tarim Basin igneous intrusive abnormally high heat stress bitumen carbon isotope PAH

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Improved Algebraic Model for Serial Production Lines with Limited Buffer Sizes

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International Journal of Minerals,Metallurgy and Materials 1999年第2期13卷 139-143页

作者： Ke Liu Zhichun Mu Datai Yu Dal Koshal David Pearce(information Engineering school,{2., of Science and Technology beijing,{4.) (school of Engineering, {2. of Brighton, Brighton Brighton BN2.4.J UK Univ of Science and Technology Beijing Beijing China

The ordered event model is improved to describe serial production lines with limited buffer sizes. The improved model hasthe same computational burden as the original one and can be constrUcted directly according to given principles. Several simulationexamples are cited to verify this improved model. Extensions and open problems are also indicated. By means of this new model, serialProduotion lines with limitations of resources can be stUdied analytically.

关键词： ordered event model serial production line buffer size period

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Characteristics of Ore-Forming Fluids of Gold Deposits in Daqingshan District,Inner Mongolia,china

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International Journal of Minerals,Metallurgy and Materials 1999年第2期13卷 77-82页

作者： Jiuhua Xu YulingXie Dayi Qian Rufu Dine Jianping Li (Resource Engineering school, university of Science and Technology Beijha{2.) (china university of geosciences,{2.) Resource Engineering school University of Science and Technology Beijing Beijing 100083 China china university of {2.sciences Beijing 100083 China

***-weststrikingductileshearzonewithinagreelt,***:(1)pyrite-quartz,(2.quartz-Pyrite,(3)polymetallicsulfidesand(4.***-bearingveinsarenativegold,electrum,pyrite,chalcopyriteandgalena,buttheganguemineralsaremainlyquartz,secondarilysericite,***,silicification,***-formingfluidswerelowinsalinitieandhighinCO2.ontent,MeasuredδDoffluidinclusionsinquartzfromtheoreveinsrangesfrom-65‰to-104.,butδ18Oquartzfrom10.0‰to12.8‰.Thesedatashowthatthewaterinhydrothermalfluidprecipitatingtheorebodiescouldhavebeenmainlymagmaticwaterandmetamorphicwaterbutlocalmeteoricwatermighttakepartinthelatemineralization.δ13Cfromfl

关键词： fluid inclusions isotope composition gold deposit Daqingshan area

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The steady-state solution of dendritic growth from the undercooled binary alloy melt with the far field flow

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Science china(Technological Sciences) 2009年第8期52卷 2280-2287页

作者： CHEN MingWen1,2. WANG ZiDong2.& XU JianJun2.3,4.1 school of Applied Sciences, {2. of Science and Technology beijing, beijing 100083. china 2.school of Materials Science and Engineering, {2. of Science and Technology beijing, beijing 100083. china 3 school of Mathematical Sciences, Nankai {2., Tianjin 300071, china 4.Department of Mathematics and Statistics, McGill {2., Montreal H3A 2.6, Canada school of Applied Sciences University of Science and Technology Beijing Beijing China school of Materials Science and Engineering University of Science and Technology Beijing Beijing China school of Mathematical Sciences Nankai University Tianjin China Department of Mathematics and Statistics McGill University Montreal Canada

The steady-state dendritic growth from the undercooled binary alloy melt with the far field flow is considered. By neglecting the interface energy, interface kinetics and buoyancy effects in the system, we obtaine the steady-state solution for the case of the large Schmidt number, in terms of the multiple variable expansion method. The changes of the temperature and concentration fields, the morphology of the interface, the normalization parameter and the Peclet number of the system induced by uniform external flow are derived. The results show that, compared with the system of dendritic growth from undercooled pure melt, the convective flow in the system of growth from undercooled binary alloy has stronger effects on the morphology of the interface. Nevertheless, the shape of the interface still remains nearly a paraboloid.

关键词： binary alloy melt convection dendritic growth interfaces steady-state solution multiple variable expansion method

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The evolution and morphological stability of a spherical crystal

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Science china(Technological Sciences) 2008年第3期51卷 225-243页

作者： CHEN MingWen1,2. WANG ZiDong2.& XU JianJun3,4.1 school of Applied Sciences, {2. of Science and Technology beijing, beijing 100083. china 2.school of Materials Science and Engineering, {2. of Science and Technology beijing, beijing 100083. china 3 school of Mathematical Sciences, Nankai {2., Tianjin 300071, china 4.Department of Mathematics and Statistics, McGill {2., Montreal H3A 2.6, Canada school of Applied Sciences University of Science and Technology Beijing Beijing China school of Materials Science and Engineering University of Science and Technology Beijing Beijing China school of Mathematical Sciences Nankai University Tianjin China Department of Mathematics and Statistics McGill University Montreal Canada

The growth model of a spherical crystal in the undercooled melt including the surface energy, interfacial kinetics and convective flow is established. The effect of the convective flow induced by a small far field flow on the evolution and morphological stability of the interface of the spherical crystal is studied. The interface shape of the spherical crystal, which is affected by the far field flow, and the dispersion relation of the growth rate of amplitude of the perturbed interface are derived. It is shown that the convection induced by the far field flow makes the interface of the growing spherical crystal further grow in the upstream direction of the far field flow and inhibit growth in the downstream direction; the interface of the decaying spherical crystal further decays in the upstream direction and inhibits decay in the downstream direction. The theoretical result suggests that both the growth of the sphere in the upstream direction and the decay of the sphere in the downstream direction make the spherical crystal tend to evolve into an oval; the morphological stability of the interface depends on a certain radius R c such that the spherical crystal is unstable when its radius is greater than R c and stable when its radius is less than R c . The surface energy and interfacial kinetics have strong stabilizing effects on the growth of the spherical crystal. In the meantime interfacial kinetics is a table factor of the interface when the interface of the sphere is growing; it is an unstable factor of the interface when the interface is decaying.

关键词： solid-liquid interface spherical crystal convective flow crystal growth morphological stability

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