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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, beijing 100083, china 2. Key Laboratory of Oil and Gas Reservoir of Petrochina, beijing 100083, china 3. china university of geosciences, beijing 100083, china 4. Institute of Geology, china Earthquake Administration, beijing 100029, china 1. Research Institute of Petroleum Exploration and Development 100083 Beijing China 2. Key Laboratory of Oil and Gas Reservoir of Petrochina 100083 Beijing China 3. china university of geosciences 100083 Beijing China 4. Institute of Geology China Earthquake Administration 100029 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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Lithosphere types in North china:Evidence from geology and geophysics

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Science china Earth Sciences 2005年第11期48卷 1809-1827页

作者： QIU Ruizhao1,2, DENG Jinfu3. ZHOU Su3. LI Jinfa4, XIAO Qinghui1,5, WU Zongxu6 & LIU Cui3.1. Institute of Geology, Chinese Academy of Geological Sciences, beijing 10003., china 2. Development and Research Center, china Geological Survey, beijing 10003., china 3. china university of geosciences, beijing 100083, china 4. china university of geosciences, Wuhan 43.074, china 5. Information Center of Ministry of Land and Resources, beijing 100812, china 6. Institute of Geology, State Seismological Bureau, beijing 100029, china 1. Institute of Geology Chinese Academy of Geological Sciences 100037 Beijing China 2. Development and Research Center China Geological Survey 100037 Beijing China 3. china university of geosciences 100083 Beijing China 4. china university of geosciences 430074 Wuhan China 5. Information Center of Ministry of Land and Resources 100812 Beijing China 6. Institute of Geology State Seismological Bureau 100029 Beijing China

On the basis of the characteristics of geology and geophysics in North china, three types of lithosphere, namely, the cratonic, the orogenic and the rift lithospheres can be classified. In terms of petrological method (based on the information from Precambrian rock assemblages, igneous activities, deep-seated enclaves, etc.) and the relationship between seismic velocity and rock compositions, the crust-mantle petrological and chemical structure models can be set up. Researching results indicate that the geology and geophysics of North china platform bears the similar characteristics in comparison with those of the global typical cratons. The Eerduosi(Ordos) block located in the west of the North china Platform is a remnant of cratonic lithosphere after the North china platform had undergone “activation” in Mesozoic and “reconstruction” in Cenozoic times. The continental crust consists mainly of TTG rock assemblage while the subcontinental lithosphere mantle mainly consists of strongly depleted harzburgite. The craton was finally formed in late Archaean and early Proterozoic, and has been kept in stability up to present; its crustal-mantle petrological structures of lithosphere can be set up as a reference for the study of North china craton and even Sino-Korean craton. In the Mesozoic period, the middle and east areas of North china platform were activated in the Yanshanian orogenic process, the continental crust was reformed by material and heat-transfer of convective mantle and the original crustal TTG component was reconstructed to be granitic crust, and the subcontinental lithosphere man- tle was replaced by the Yanshanian harzburgite-lherzolite. The Yanshan-Taihang Mountains were the remnants of orogenic lithosphere after the rifting in eastern North china in Cenozoic. The present thickness of continental crust and lithosphere in the Yanshan-Taihang Mountains is not equal to their thickness during the Yanshanian orogenic movement because they had undergone the

关键词： lithospheric types,evidence of geology and geophysics,crust-mantle petrological structure,deep process

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Spatio-temporal model for soil characteristic of reclamation land

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中国有色金属学会会刊：英文版 2005年第S1期15卷 45-48页

作者： CHEN Qiu-ji~(1, 2), HU Zhen-qi~1, FU Mei-chen~3. XIE Hong-quan~4, HAO Hai-fu~5 (1. china university of Mining and Technology(beijing Campus),{3., china 2. Henan Polytechnic university, Jiaozuo 454000, china 3. china university of geosciences,{3., china 4. Hebei Polytechnic university, Tangshan 063.09, china 5. china Railway Shiqiju Group Corporation, Taiyuan 03.600, china) china Univ Min & Technol Beijing 100083 Peoples R China Henen Polytech Univ Jiaozuo 45400 Peoples R China china Univ Geosci Beijing 100083 Peoples R China Hebei Polytech Univ Tangshan 063009 Peoples R China china Railway Shiqiju Grp Corp Taiyuan 030600 Peoples R China

The development of spatio-temporal data model is introduced. According to the soil characteristic of reclamation land, we adopt the base state with amendments model of multi-layer raster to organize the spatio-temporal data, using the combined data structure on linear quadtree and linear octree to code. The advantage of this model is that it can easily obtain the information of certain layer and integratedly analyze the data with other methods. Then, the methods of obtain and analyses are introduced. The method can provide a tool for the research of the soil characteristic change and spatial distribution in reclamation land.

关键词： reclamation soil spatio-temporal data model linear quad-tree linear octree

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Experimental studies of tired-mineral interaction in low temperature

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Chinese Science Bulletin 1999年第S2期44卷 169-171页

作者： GAO Liping~1, YANG Weidong~1, LUO Xiaojun~1, JIA Hongyu~2, ZENG Jianhui~2, YU Bingsong~3.and LAI Xingyun~3.1. Open laboratory of Ore Deposit Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002, china 2. university of Petroleum, beijing 102200, china 3. china university of geosciences, beijing 100083, china

THE physical properties of petroleum and natural gas reservoirs (porosity, permeability, etc.) are important parameters reflecting the quality of the reservoirs, so they are of important significance in the exploration and the development of petroleum and gas. Most of oil and gas resources in china are stored in thefragmental reservoir of continental basin. Not only the primary sedimentary factors but also the diageneticchanges after deposition affect the physical properties of the reservoir. And the diagenetic change, infact, is the interaction of fluid and minerals in low temperature. This note is about some experimental studies on the ordinary minerals in fragmental reservoir such asalkali feldspar and plagioclase and discusses the experimental results of the interaction between the fluidsand these two kinds of feldspar in different pH values and different media. The chemical composition and structural formula of the samples used in these experiments are

关键词： fluid-mineral interaction experimental studies.

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根据原油的含氮化合物判断东营凹陷大芦湖油田油气运移方向

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天然气地球科学 2004年第6期15卷 650-651页

作者：郑有恒黄海平文志刚陈永峤朱建辉中国地质大学(武汉) 中国地质大学(北京) 北京100083 长江大学湖北荆州434023 中国石化石油勘探开发研究院无锡实验地质研究所江苏无锡214151

利用非烃中的含氮化合物作为石油运移示踪剂,探讨了东营凹陷大芦湖油田的油气运移方向。对原油中含氮化合物的丰度、异构体参数的绝对大小与相对变化的研究结果表明,该油田原油间运移分馏效应明显,推测原油的主运移方向是由北向南。

关键词：原油石油运移含氮化合物分馏效应大芦湖油田

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The Thermal Structure of the Upper Mantle in Eastern china——Inferred from the Petrological Model

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Acta Geologica Sinica(English Edition) 1991年第2期65卷 195-201页

作者： Deng Jinfu and Zhao Hailing china university of geosciences,{3., china china university of geosciences Beijing 100083 China

Cenozoic basalt in eastern china contains abundant ultramafic xenoliths which are specimens of pyrolitesreleased during basaltic magma eruption. A total of 405 P-T data of pyroxene in the ultramafic rocks have beencollected, which present a more precise pyroxene geotherm. The average geothermal gradient in the upper man-tle represented by the pyroxene geotherm is about 3.3. / km, which is much less than that derived from theconductive thermal model (≈14℃ / km), implying the great significance of convective heat transfer. The calcu-lation shows that the contributions of convective and conductive heat transfers are 79% and 21%, *** perturbation in the thermal structure of the upper mantle is an important manifestation of thetectonothermal event of Cenozoic continental rifting and intense basaltic volcanism in eastern china. Based onthe pyroxene geotherm and its comparison with the current geothermal field derived from the measurements ofthe surface heat flows, it is suggested that the Moho may be a secondary thermal boundary. The currentgeothermal field and the thermal structure of the lithosphere in eastern china may mainly reflect the result ofthe tectonothermal disturbance in the Neogene-Quaternary, in other words, the lithosphere has just begun toCool.

关键词： The Thermal Structure of the Upper Mantle in Eastern china

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Identifying rock blocks based on hierarchical rock-mass structure model

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Science china Earth Sciences 2009年第10期52卷 1612-1623页

作者： XU NengXiong School of Engineering and Technology, china university of geosciences,{3., china School of Engineering and Technology China University of Geosciences Beijing 100083 China

Rock-masses are divided into many closed blocks by deterministic and stochastic discontinuities and engineering interfaces in complex rock-mass engineering. Determining the sizes, shapes, and adjacent relations of blocks is important for stability analysis of fractured rock masses. Here we propose an algorithm for identifying spatial blocks based on a hierarchical 3. Rock-mass Structure Model (RSM). First, a model is built composed of deterministic discontinuities, engineering interfaces, and the earth's surface, and the deterministic blocks surrounded by these interfaces are traced. Then, in each deter-ministic block, a network model of stochastic discontinuities is built and the stochastic blocks are traced. Building a unitary wire frame that connects all interfaces seamlessly is the key for our algorithm to identify the above two kinds of blocks. Using this algorithm, geometric models can be built for block theory, discrete element method, and discontinuous deformation analysis.

关键词： rock-mass engineering discontinuity block identification 3. Rock-mass Structure Model network model of stochastic discontinuities

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Origin,evolution and extinction of Cathaysia flora

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Chinese Science Bulletin 1999年第2期44卷 100-108页

作者： SUN Keqinchina university of geosciences,{3., china china university of geosciences Beijing China

Recent research results showed that the Cathaysia flora originated and developed from the global uniform Lepidodendropsis flora of the Early Carboniferous, which had already become an independent flora in the early Late Carboniferous (Namurian B to C). The center of origin of the Cathaysia flora is restricted to the North china Plate. On the basis of the successional characteristics of the Cathaysia flora in different geological ages, it may be divided into seven evolutionary stages. The evolutionary trend of the Cathaysia flora, as a whole, was characterized by the gradual increase of the typical Cathaysian elements in the sequence from the early Late Carboniferous to the early Late Permian, which began to decline during the late Late Permian. The climatic differentiation, tectonic movement,oceanic circulation, palaeogeographical environment, extraterrestrial event and plant evolution caused the mass extinction of the Cathaysia flora on a large scale by the end of the Permian.

关键词： Asia Cathaysia flora origin evolution extinction Late Carboniferous Permian.

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CORRELATION BETWEEN STRESS COMPONENTS AND STRESS CORROSION CRACKS IN BRASS Lecturer,Department of Materials Physics,university of Science and Technology beijing,beijing {3.,china

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Acta Metallurgica Sinica(English Letters) 1992年第9期5卷 178-182页

作者： QIAO Lijie LIU Rui XIAO Jimei university of Science and Technology beijing,beijing,{3.

The effects of stress components on nucleation sites and propagation directions of stress cor- rosion cracks in brass were investigated with specimens under mode Ⅱ and mode Ⅲ loadings. The results indicated that under mode Ⅱ loading,stress corrosion cracks nucleated on the site with maximum normal stress component and propagated along the plane perpendieular to the maximum normal stress,under mode Ⅲ loading,the stress corrosion crack was not evident on the 45°plane due to the general corrosion in aqueous solution with high NH_4OH concentra- tion,while stress corroded in aqueous solution with low NH_4OH concentration, numerous cracks with spacings of 10—150μm were found on the 45°plane with maximum normal stress and no stress corrosion cracks was observed on the plane with maximum shear stress.

关键词： stress corrosion cracking stress compoonent brass ammonia solution

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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 beijing 100083, china) ({3. university of geosciences, beijing 100083, china) Resource Engineering School University of Science and Technology Beijing Beijing 100083 China china university of geosciences Beijing 100083 China

***-weststrikingductileshearzonewithinagreelt,***:(1)pyrite-quartz,(2)quartz-Pyrite,(3.polymetallicsulfidesand(4)***-bearingveinsarenativegold,electrum,pyrite,chalcopyriteandgalena,buttheganguemineralsaremainlyquartz,secondarilysericite,***,silicification,***-formingfluidswerelowinsalinitieandhighinCO2content,MeasuredδDoffluidinclusionsinquartzfromtheoreveinsrangesfrom-65‰to-104‰,butδ18Oquartzfrom10.0‰to12.8‰.Thesedatashowthatthewaterinhydrothermalfluidprecipitatingtheorebodiescouldhavebeenmainlymagmaticwaterandmetamorphicwaterbutlocalmeteoricwatermighttakepartinthelatemineralization.δ13.fromfl

关键词： fluid inclusions isotope composition gold deposit Daqingshan area

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