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The Carboniferous at the Northern Foot of the Dabie Mountains and Its Tectonic Implications

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Acta Geologica Sinica(English Edition) 1991年第3期65卷 237-249页

作者： Ma Wenpu china university of geosciences, Beijing Fei Zhenbi china university of geosciences Beijing

In the Qinling orogenic belt. oceanic crust originated in the Early Palaeozoic. while the product of conti-nental collision appeared as late as after the Triassic. The Late Palaeozoic records there are of major impor-tance for understanding the tectonic regime at that time. The Carboniferous and even Permian sequences andthe distribution of sedimentary facies in northern Huaiyang indicate that the rocks were formed in a large basinopening towards the south. Regional stratigraphic correlation shows that the interior of the Qinling orogenicbelt was a sea trough lying between the Yangtze and North china plates in the middle part of the LatePalaeozoic. With subsequent northward migration of the South china Sea, the two seas were connected witheach other. Both the melanges and the Dabie block ia the eastern sector of the Qinling belt were formed in theMesozoic ?.

关键词： The Carboniferous at the Northern Foot of the Dabie Mountains and Its Tectonic Implications

The Dynamic Mechanisms for the Formation of Primary Metal Zoning of Cassiterite-Sulfide Deposits in the Gejiu Metallogenic Province, Yunnan

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Acta Geologica Sinica(English Edition) 1991年第1期65卷 51-63页

作者： Yu Chongwen Jiang Yaosong china university of geosciences, Beijing china university of geosciences Beijing

Copper and tin in cassiterite-sulfide deposits of the Gejiu metallogenic province are intimately associatedand show peculiar primary metal zoning. The authors made use of computer techniques to simulatenumerically the zoning of these ore deposits. The study shows that the regular spatial zoning probably resultedfrom the succession of multiple, intermittent and pulsatory mineralizations, The successive transports with di-verse velocities along channelways of the ore-forming solutions, taking place under conditions of definite dif-ference between metal concentrations, in solutions and wallrocks, followed by differential deposition, consti-tute possible dynamic mechanisms for the primary metal zoning.

关键词： Met rate The Dynamic Mechanisms for the Formation of Primary Metal Zoning of Cassiterite-Sulfide Deposits in the Gejiu Metallogenic Province Yunnan

The Depositional Environment of the Cretaceous Kizilsu Group in Xinjiang——With a Discussion of the Lowermost Marine Horizon of the Cretaceous in the Western Tarim Basin

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Acta Geologica Sinica(English Edition) 1991年第4期65卷 441-453页

作者： Guo Xianpu china university of geosciences, Beijing Sun Sheping china university of geosciences Beijing

In this paper. it is demonstrated that there exist marine horizons in the upper part of the lower subcycleand the upper subeycle of the Kizilsu Group in Xinjiang. based on new evidence of authigenic glauconite.boron content. carbon and oxygen stablc isotopic analyses. and lithological and sedimentary features. The up-per part of the lower subeycle is the lowermost marine horizon of the Cretaceous in the western Tarim Basin,which is inferred to be of Barremian age.

关键词： In With a Discussion of the Lowermost Marine Horizon of the Cretaceous in the Western Tarim Basin The Depositional Environment of the Cretaceous Kizilsu Group in Xinjiang

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, Beijing 100083, 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

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, Beijing 100083, china School of Engineering and Technology China University of Geosciences Beijing 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 3D 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 3D Rock-mass Structure Model network model of stochastic discontinuities

Tectonic Factors Favourable for the Formation of Evaporites in the Indosinian Period in Hubei and Its Neighbouring Areas

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Acta Geologica Sinica(English Edition) 1988年第4期1卷 381-391页

作者： Li Shiruo china university of geosciences, Wuhan, Hubei china university of geosciences Wuhan Hubei

In the Indosinian period. the climate was scorching hot and the source of seawater was ample in Hubeiand its neighbouring areas. so the basic conditions for the formation of evaporites were favourable. Under thisprerequisite. the reason why salt deposits occurring in some third-order tectonic units between the Jiangnanoldland-upwarped zone and the Dabashan upwarped zone differ in degree of development is mainly due to thetectonic factors during sedimentation. If favourable tectonic factors are present, large amounts or evaporiteswill form: on the contrary. they will not.

关键词： In

Middle and Late Carboniferous Tetracoral Assemblages and Biogeography of china

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Acta Geologica Sinica(English Edition) 1989年第2期63卷 103-114页

作者： Wang Zhiping china university of geosciences, Wuhan, Hubei Liu Linqun china university of geosciences Wuhan Hubei

china is rich in Middle and Carboniferous fossil corals. The coral faunas in different regions have varying characteristics and can be divided into distinct assemblages. The coral fauna in South china is dominated by the order Caninida and contains numerous endemic elements; that in North china has a lot of Middle Carboniferous corals which are monotonous in species, with Late Carboniferous solitary corals being predominant. The coral fauna in Junggar mainly contains large bi-zoned solitary caninids, while that in southern Khingan is similar to that in South china due to the presence of abundant tri-zoned compound corals. In northern Tibet the coral fauna is also similar to that in South china, but in southern Tibet it is of a cold-water type. Therefore, the Middle and Late Carboniferous coral geography of china can be divided into the Tethys, Boreal and Gondwana Realms.

关键词： La Middle and Late Carboniferous Tetracoral Assemblages and Biogeography of china

Oxfordian (Jurassic) mayaitid (ammonite) dispersal in the Tibetan Himalaya as the first signal of the establishment of the Indo-Austrai subrealm

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Progress in Natural Science:Materials International 2003年第4期13卷 44-49页

作者： YIN Jiarun(china university of geosciences, Beijing 100083, china) china Univ Geosci Beijing 100083 Peoples R China

New fossil collections in the Lanongla area, Tibetan Himalaya enables the establishment of the Upper Jurassic ammonoidsuccession. Middle Oxfordian ammonite-fauna is characterized by endemic epimayaittds with a marine deepening event, suggesling a high stand of sea Ievel in the Tibetan Himalaya. Distribution of mayaitids around the Eastern Gondwana can be regarded as the first signal of the Indo-AustraI Subrealm that was progressively established during the Late Jurassic and Early Cretaceous times.

关键词： Jurassic Oxfordian ammonites Tibetan Himalaya Indo-Austral Subrealm.

Development of SPM Quantitative Micromorphology Analysis Software

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International Journal of Minerals,Metallurgy and Materials 1999年第2期13卷 136-138页

作者： Suozai Li Libing Liao(School of Materials Science and Engineering, china university of geosciences, Beijing 100083, china) School of Materials Science and Engineering China University of Geosciences Beijing 100083 China

Scanning Probe Microscope (SPM) has great advantages in quantitative micromorphology analysis because of its conveniencein obtaining micromorphology information of materials on nanometer or atomic scale under control of a computer. Based on an established SPM quantitative micromorphology analysis model, an SPM image analysis software Which can calculate both two- and three-dimensional micromorphology parameters is developed.

关键词： SPM quantitative micromorphology analysis software