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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

Singular Integral Equations with Cosecant Kernel in Solutions with Singularities of High Order

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Wuhan university Journal of Natural Sciences 2005年第2期10卷 339-343页

作者： HAN Hui-li 1,2 ,DU Jin-yuan 1,3.1. School of Mathematics and Statistics, Wuhan university, Wuhan 43.072, hubei, {3. 2. School of Mathematics and Computer, Ningxia university, Yinchuan 750021, Ningxia, {3. 3. Department of Mathematics, hubei Institute for Nationalities, Enshi 445000, hubei, {3. Wuhan university School of Mathematics and Statistics Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***) Ningxia university School of Mathematics and Computer Yinchuan Ningxia China (GRID:grid.260987.2) (ISNI:***) Wuhan university School of Mathematics and Statistics Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***) hubei Institute for Nationalities Department of Mathematies Enshi Hubei China (GRID:grid.34418.3a) (ISNI:***)

We have discussed and solved the boundary value problem with period 2aπ and the singular integral equation with kernel csc t-tv/a in solution having singularities of high order, where the smooth contour of integratio... 详细信息

关键词： boundary value problem singular integral equation the singularities of high order

On the siltation of the middle Yangtze River

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Science china Earth Sciences 2004年第5期47卷 463-480页

作者： YIN Hongfu1, CHEN Guojin2, li Chang抋n1 & WEI Yuan3.1. School of Earth Sciences, china university of {3., Wuhan 43.074, china 2. Hydrogeological Team, hubei Bureau of Geology and Mineral Resources, Jingzhou 43.100, china 3. Geological Survey of Jiangxi Province, Nanchang 3.0201, china china Univ Geosci Sch Earth Sci Wuhan 430074 Peoples R China hubei Bur Geol & Mineral Resources Hydrogeol Team Jinzhou 434100 Peoples R China Geol Survey Jiangxi Province Nanchang 3300201 Peoples R China

About 5.2×108 t/a of silts from the upper reach of the Yangtze River are transported through Yichang into the middle Yangtze River. The middle Yangtze itself and its tributaries yield ca. 0.8×108 t silts annually. Of this total 6×108 t/a input of silts, ca. 1.2×108 t/a are deposited within the river artery and lakes, while ca 4.83.108 t/a are at first transported into the lower reach through Datong, and then either deposited along the river and the Yangtze Delta, or output into the sea. Along the middle Yangtze River silting generally exceeds scouring, but the spatial and temporal distributions of scour-and-fill, as well as its distribution in the river valley transections, are uneven. Along the Yichang-Chenglingji and Jiujiang-Datong Segments of the middle Yangtze, scouring exceeds or equals silting. Silting mainly occurs along the Luoshan-Wuhan-Huangshi Segments with Wuhan as the pivotal point, as well as in the Dongting and Poyang Lakes. Even in these silting-dominated areas, there are times and parts of segments that scouring prevails. As to the transections, generally the river channel of main stream is scouring-dominated, forming V-shaped sections to a depth of 203. m or more, whereas the floodplains and bar islands are silting-dominated, forming wide and relatively high flats, which are often artificially transformed into protected embankments. Because the Jingjiang Levee separates the Jianghan Plain from Yangtze to the south, little has been deposited in that plain except a few sediments from the Han River—a tributary of the middle Yangtze. This factor plus the tectonic sag of that plain has made the altitude of plain surface several meters lower than that of the levee in most of the areas. Sil-tation along the Luoshan-Wuhan-Huangshi Segments has resulted in the elevation of flood level in this and upstream segments. River channel scouring plus floodplain silting have caused the transections of the middle Yangtze valley typically with deep channel and height

关键词： the middle Yangtze, scour-and-fill, siltation, silt utilization.

Experimental remolding on the caprock's 3. strain field of the Indosinian-Yanshanian epoch in Tongling deposit concentrating area

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Science china Earth Sciences 2005年第7期48卷 863-874页

作者： DENG Jun1,HUANG Dinghua2,WANG Qingfei1,WAN li1,SUN Zhongshi3.YANG liqiang1 & GAO Bangfei1 1. State Key Laboratory of Geological Processes and Mineral Resources,china {3. of geosciences,Beijing 100083.china 2. Faculty of Earth Sciences,china {3. of geosciences,Wuhan 43.074,china 3. Department of Earth Sciences,Jilin {3.,Changchun 13.061,china State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Beijing 100083 China Faculty of Earth Sciences China University of Geosciences Wuhan 430074 China Department of Earth Sciences Jilin University Changchun 130061 China

Based on field observations and rheology analysis, we perform one analogue experiment and remold the 3. structural frame of Tongling deposit concentrating area firstly. Then we disassemble and dialyze the 3. structures of the model using the methods of "slicing" and "stripping". A series of sliced planes vertical to the fold hinges show similar landscapes of that in the drill hole profiles. Meanwhile, layer stripping analysis indicates that the deformation features of each layer in the model are qualitatively analogical to those obtained from field observations. Through contrasting the 3. structure between the experimental model and the field phenomena, we verify the following 3. deformation features of the caprock in this area: (1) the Tongling area mainly consists of three series of NE S-typed fold groups; (2) in the uniform stress field, the incoherent folds universally develop in different positions, along different axes as well as in different strata; (3. the faults propagate upward which are mostly inter-bedded detachment faults, while the fold amplitudes decrease while going deeper; and (4) the folds and cleavages are highly developed in the Silurian System indicating that the deformation effect of the Indosin-ian-Yanshanian structural layer terminates at this layer, which suggests that the Silurian System is the crucial layer for the inversion between brittle and plastic deformation domains and the underlying strata are subject to the control of another deformation system with distinct properties.

关键词： Tongling deposit concentrating area Indosinian-Yanshanian epoch 3. structural frame of the caprock analogue experiment slicing and stripping analysis structural model.

Petrogenesis and dating of the Kangding complex,Sichuan Province

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Science china Earth Sciences 2005年第5期48卷 622-634页

作者： CHEN Yuelong 1 , LUO Zhaohua 1 , ZHAO Junxiang, li Zhihong, ZHANG Hongfei & SONG Biao 3.1. Faculty of Earth Sciences and Natural Resources, china university of {3., Beijing 100083. china 2. Faculty of Earth Sciences, china university of {3., Wuhan 43.074, china 3. Beijing SHRIMP Center, Institute of Geology, Chinese Academy of Geological Sciences, Beijing 10003., china 1. Faculty of Earth Sciences and Natural Resources China University of Geosciences 100083 Beijing China 2. Faculty of Earth Sciences China University of Geosciences 430074 Wuhan China 3. Beijing SHRIMP Center Institute of Geology Chinese Academy of Geological Sciences 100037 Beijing China

An analysis of major and trace element geochemistry and SHRIMP U-Pb zircon dating of mafic, intermediate, and felsic rocks from the Mianning metamorphic complex of Si- chuan Province was conducted. One of our conclusions is that a majority of the zircons crystal- lized between 721 and 773.Ma in a magmatic regime. The complexes contain early to late Pa- leo-proterozoic relict zircons from ancient continental crust. The oldest age, 2468 Ma, may rep- resent the basement of the Yangtze block. Overgrowth zircon rims and palingenetic zircons have been observed and dated, and are believed to have formed after crystallization, during Paleozoic and Mesozoic metamorphic-anatexis. We also conclude that depletion of Nb, Ta, HREE, in a spider-diagram normalized to primitive mantle and calc-alkaline association, implies that they formed in island-arc or under-plating settings.

关键词： Kangding complex, zircons, SHRIMP, tectonic setting.

Petrogenesis of Songshugou dunite body in the Qinling orogenic belt, Central china: Constraints from geochemistry and melt inclusions

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Science china Earth Sciences 2005年第8期48卷 1146-1157页

作者： SU li1,2, SONG Shuguang3.& ZHOU Dingwu1 1. Key Laboratory of Continental Dynamics of the Ministry of Education, Department of Geology, Northwestern university, Xi’an 710069, china 2. The Geological Lab Center, china university of geosciences (Beijing), Beijing 100083. china 3. Key Laboratory of Orogenic Belts of the Ministry of Education, Department of Geology, Peking university, Beijing 100871, china 1. Key Laboratory of Continental Dynamics of the Ministry of Education Department of Geology Northwestern University 710069 Xi’an China 2. The Geological Lab Center China University of Geosciences 100083 (Beijing)Beijing China 3. Key Laboratory of Orogenic Belts of the Ministry of Education Department of Geology Peking University 100871 Beijing China

The Songshugou dunite body, which occupies an area of about 20 km2, is the largest ultramafic massif in the eastern Qinling orogenic belt, Central china. The major compo-nent of this body is dunitic rocks including mylonitic dunite and coarse-grained dunite; they oc-cupy about 95 vol% of the total body. Petrography, mineral composition, major and trace ele-ments and primitive melt inclusions have been investigated in this paper; all revealed that this dunite body is the product of melt-rock interaction by porous percolation flow. In comparison with dunite sills or veins in harzburgite from the basal part of Oman ophiolite, this dunite body is characterized by lower contents of Al2O3. CaO and HREE but higher content of highly incom-patible elements and Zr and Hf. The LREE enriched patterns and primitive mantle normalized spidergrams of trace elements are also different from the Oman dunite. Combining with melt in-clusions observed in olivines, we conclude that this dunite body is the product of large- scale porous percolation flow of high-MgO melts within depleted mantle peridotites. The high-MgO magma, in essence, was most probably produced at the hot head of an upwelling mantle plume. The occurrence of the Songshugou dunite body is closely associated with the activity of mantle super-plume in Neo-Proterozoic era in the Yangtze Craton.

关键词： Songshugou dunite body, geochemistry, melt inclusion, mantle plume, Qinling orogenic belt.

Sm-Nd and zircon SHRIMP U-Pb dating of Huilanshan mafic granulite in the Dabie Mountains and its zircon trace element geochemistry

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Science china Earth Sciences 2005年第12期48卷 2081-2091页

作者： HOU Zhenhui1, li Shuguang1, CHEN Nengsong2, li Qiuli1 & liU Xiaoming3.1. School of Earth and Space Sciences, university of Science and Technology of china, Hefei 23.026, china 2. The Key Laboratory of Continental Dynamics of the Ministry of Education, Northwest university, Xi’an 710069, china 3. Faculty of Earth Sciences, china university of geosciences, Wuhan 43.074, china 1. School of Earth and Space Sciences University of Science and Technology of China 230026 Hefei China 2. The Key Laboratory of Continental Dynamics of the Ministry of Education Northwest University 710069 Xi’an China 3. Faculty of Earth Sciences China University of Geosciences 430074 Wuhan China

The mafic granulites from Huilanshan are outcropped on the center of the Luotian dome in the northern Dabie Mountains. The Sm-Nd isochron defined by granulite-facies meta-morphic minerals (garnet + clinopyroxene + hypersthene) yields an age of 13. ± 18 Ma indicating the early Cretaceous granulite-facies metamorphism. The cathodoluminescence (CL) images of zircons from the granulite show clearly core-mantle-rim structures. The zircon cores are charac-terized by typical oscillatory zoning and highly HREE enriched patterns, which suggests their magma origin. Some zircon cores among them with little Pb loss give SHRIMP U-Pb ages rang-ing from 753.to 780 Ma, which suggests that the protolith of Huilanshan granulite is Neopro-terozoic mafic rocks. The zircon mantles usually cut across the oscillatory zone of the zircon cores have 3.10 times lower REE, Th, U, Y, Nb and Ta contents than the igneous zircon cores but have high common Pb contents. These characteristics suggest that they were formed by hydrothermal alteration of the igneous zircons. The part of zircon mantles with little Pb loss give a similar SHRIMP U-Pb age (716―780 Ma) to the igneous zircon cores, which implies that the hydrothermal events occurred closely to the magmatic emplacement. In view of the strong early Cretaceous magmatism in the Luotian dome, consequently, the Huilanshan mafic granulite was formed by heating of the Neoproterozoic mafic rocks in mid-low crust, which caused the granu-lite-facies metamorphism underneath the Dabie Mountains. The similarity between the granulite metamorphic age (13. ± 18 Ma) defined by Sm-Nd isochron and K-Ar age of 123.127 Ma given by amphible from the gneiss in Luotian dome suggests a rapid uplifting of the Luotian dome, which may result in further exhumation of the ultrahigh pressure metamorphic rocks in the Dabie Mountains.

关键词： Dabie orogen, granulite, zircon U-Pb ages, Sm-Nd age.

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, {3. university of geosciences, Beijing 100083. {3.) 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

Effect of SPM Scanning Range on the Micromorphology Parameters

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International Journal of Minerals,Metallurgy and Materials 1998年第1期12卷 36-38页

作者： libing liao Suozai li (School of materials Science and engineering, {3. university of geosciences, Beijing 100083. {3.) School of Materials Science and Engineering China University of Geosciences Beijing 100083 China

The surface of a compact disk is analyzed by using SPM and the quantitative micromorphology analysissoftware SPMIAS developed by the author. Images at the same position but with different scanning ranges areobtained under the same experimental conditions. Micromorphology parameters are calculated and compared, andthe relationship between the changing of the scanning range and the changing of micromorphology parameters issummarized.

关键词： Scanning Probe Microscope(SPM) micromorphology micromorphology parameters

Solving A Kind of High Complexity Multi-Objective Problems by A Fast Algorithm

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Wuhan university Journal of Natural Sciences 2003年第S1期8卷 183-188页

作者： Zeng San-you, Ding li-xin, Kang li-shanDepartment of Computer Science,china {3. of geosciences, Wuhan 43.074, hubei, china Department of Computer Science, Zhuzhou Institute of Technology , Zhuzhou 412008, Hunan, china State Key Laboratory of Software Engineering, Wuhan {3., Wuhan 43.072, hubei, china china university of geosciences Department of Computer Science Wuhan Hubei China (GRID:grid.162107.3) (ISNI:***) Zhuzhou Institute of Technology Department of Computer Science Zhuzhou Hunan China (GRID:grid.162107.3) china university of geosciences Department of Computer Science Wuhan Hubei China (GRID:grid.162107.3) (ISNI:***) Wuhan university State Key Laboratory of Software Engineering Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***)

A fast algorithm is proposed to solve a kind of high complexity multi-objective problems in this paper. It takes advantages of both the orthogonal design method to search evenly, and the statistical optimal method to speed up the computation. It is very suitable for solving high complexity problems, and quickly yields solutions which converge to the Pareto-optimal set with high precision and uniform distribution. Some complicated multi-objective problems are solved by the algorithm and the results show that the algorithm is not only fast but also superior to other MOGAS and MOEAs, such as the currently efficient algorithm SPEA, in terms of the precision, quantity and distribution of solutions.

关键词： evolutionary algorithms orthogonal design multi-objective optimization Pareto-optimal set