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Chinese Science Bulletin 2001年第4期46卷 330-333页

作者： CHEN Nengsong, SUN Min, ZHANG Kexin & ZHU YunhaiFaculty of Earth Sciences, china university of geosciences, wuhan 43.074, china Department of Earth Sciences, The university of Hong Kong, Hong Kong SAR, china Faculty of Earth Sciences China University of Geosciences Wuhan China Department of Earth Sciences The University of Hong Kong Hong Kong SAR China

Single-grain zircon U-Pb and amphibole 40Ar-39Ar dating have been conducted on a deformed and metamorphosed diorite in the East Kunlun Orogenic Belt, which intruded into the middle Proterozoic Kuhai Group exposed in the south of Xiangride region, Dulan County, NW Qinghai Province. The zircon gives a concordant U-Pb age of (446.5±9.1) Ma. The amphibole yields Ar plateau age of (488.0±1.2) Ma and an isochronal age of (488.9±5.6. Ma. Age results of both stepwise released Ar and conventional K-Ar analysis are remarkably higher than that of zircon U-Pb, suggesting that the amphibole contains excess argon and the amphibole plateau age cannot be taken as the timing of metamorphism or deformation. The zircon age is interpreted to be crystallization age of the diorite pluton, which suggests that an Early-Paleozoic magmatic zone indeed existed in the East Kunlun Orogenic Belt stretching along the region south to the Golmud, Normuhong and Xiangride.

关键词： East Kunlun Orogenic Belt metadiorite geochronology excess argon.

Palaeogene Biostratigraphic Characteristics of Red Basins In Western Henan and Its Adjacent Areas, With an Outline of Palaeogene Palaeobiogeographic Provinces of china

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Acta Geologica Sinica(English Edition) 1992年第1期66卷 101-117页

作者： Du Hengjian Ma Ancheng Cheng Jie Wu Weimin china university of geosciences, Beijing Beijing Normal university china university of geosciences, Beijing Institute of Crustal Dynamics, State Seismological Bureau, Beijing china university of geosciences Beijing China

This article is a preliminary summary of Paleogene biostratigraphy of the Liguanqiao, Tantou andYuanqu basins, with a new proposal for Paleogene paleobiogeographic provinces of china. On the basis of asynthetic analysis of the geological data, characters of the mammalian assemblages and their comparisons withother corresponding faunas, a new scheme on Paleogene biostratigraphic subdivision of the basins has been putforward here. Based on differences of biostratigraphic sequences, characteristics of mammalian assemblagesand directions of faults controlling Paleogene basins in china, six Paleogene paleobiogeographic provinces ofchina have been proposed in this paper, that is: Tianshan-Yinshan-Tumen Province; Tarim-North china Prov-ince; Kunlun-Qinling Province, Yangtze Province, Nanling and Southeastern Coastal Province, Qinghai andTibet Province.

关键词： With an Outline of Palaeogene Palaeobiogeographic Provinces of china

Experimental study of ore gabbro liquid immiscibility

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Science china Earth Sciences 2005年第4期48卷 496-505页

作者： SANG Zunan1,2, XIA Bin1, ZHOU Yongsheng3 & JIN Zhenmin4 1. Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 5106.0, china 2. wuhan university, wuhan 430072, china 3. Institute of Geology, china Seismological Bureau, Beijing 100029, china 4. Faculty of Earth Sciences, china university of geosciences, wuhan 43.074, china 1. Guangzhou Institute of Geochemistry Chinese Academy of Sciences 510640 Guangzhou China 2. wuhan university 430072 Wuhan China 3. Institute of Geology China Seismological Bureau 100029 Beijing China 4. Faculty of Earth Sciences China University of Geosciences 430074 Wuhan China

In this paper, the authors present the results of a preliminary experimental study on partial melting of fine-grained gabbro, Panzhihua, Sichuan Province, china. Experiments were conducted under (confining) pressure ranging from 450 to 500 MPa and temperature of 900— 1200℃. The results show that the initial melt is distributed along grain boundaries and triple junctions. Liquid immiscibility phenomena are noted in the melt with two compositional different melt phases, i.e. matrix and sphere phases. The matrix phase is relatively rich in Si, Al and K, and is depleted in Mg, Fe, Ca, Na and Ti, whereas the sphere phase shows opposite trends. The calculation of the melt free energy indicates that the liquid immiscibility is governed by the rule of thermodynamics, as the liquid immiscibility would result in the decrease in free energy of the melt system. The field relationships suggest that the liquid immiscibility may have played an important role in the generation of ore magma of Panzhihua V-Ti magnetite ore deposit. This study thus provides experimental constraints on the mechanism of the formation of V-Ti magnetite deposite.

关键词： partial melting, experimental study, gabbro, liquid immiscibility, ore formation mechanism.

SOME BOUNDARY INCREASING PROPERTIES OF HARMONIC FUNCTIONS IN LIPSCHITZ DOMAIN

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Chinese Annals of Mathematics,Series B 1996年第2期17卷 159-166页

作者： ZHANG YIPING Department of Mathematics, wuhan university, wuhan 430072, china.Project supported by the National Natural Science Foundation of china. wuhan UNIV DEPT MATH WUHAN 430072 PEOPLES R CHINA

The object of this paper is to study the non-tangential increasing properties of positiveharmonic function u in Lipschitz domain by means of Martin representation theory. A necessaryand sufficient condition of the control of growth of u near any fixed boundary point is obtained.It is shown that the non-tangential increasing degree of u near a boundary point is exactlythe local degree of its representation measure with respect to the harmonic measure. Someexamples are given.

关键词： Martin representation Harmonic function Harmonic measure

Volcanism at the Permian-Triassic Boundary in South china and Its Effects on Mass Extinction

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Acta Geologica Sinica(English Edition) 1989年第4期63卷 417-431,450-451页

作者： Yin Hongfu, Huang Siji, Zhang Kexin, Yang Fengqing, Ding Meihua, Bi Xianmei and Zhang Suxin china university of geosciences, wuhan, Hubei china university of geosciences Wuhan Hubei

This paper discusses the clayrocks widespread at the Permian-Triassic boundary, which are mostly of volcanic origin. Volcanogenetic textures, structures and minerals such as high-temperature quartz are found in clayrocks at the Permian-Triassic boundary in many places. Thousands of microspherules have been collected from the Boundary clayrocks, many of which exhibit the typical features of the process from melting to cooling and solidification. indicating that they were formed by volcanic eruption or extraterrestrial impact. Volcanic effects on the Permian-Triassic mass extinction may be reflected in conodonts, algae and ammonoids. The Boundary clayrocks are found in many Permian-Triassic sections along the coast of Tethys. Their orighin remains to be studied.

关键词： Volcanism at the Permian-Triassic Boundary in South china and Its Effects on Mass Extinction Mass

Magnetic and mineralogical characteristics of reservoir rocks in the Yakela oil field, northern Tarim Basin and their implications for magnetic detection of oil and gas accumulations

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Chinese Science Bulletin 1999年第2期44卷 174-177页

作者： LIU Qingsheng LIU ShugerDepartment of Applied Geophysics, china university of geosciences, wuhan 43.074, china The State Key Laboratory of Oil/Gas Reservoir Geology and Exploitation of china, Chengdu Institute of TechnologyChengdu 6.0059, china Department of Applied Geophysics China University of Geosciences Wuhan China The State Key Laboratory of Oil/Gas Reservoir Geology and Erploitation of china Chengdu Institute of Technology Chengdu China

The evidence about hydrocarbon migration within reservoir rocks in two wells has been obtained according to results of magnetic and mineralogical analysis of the Kapushaliang Group reservoir rocks from wells S15 and S4 located at the Yakela oil field, Tarim Basin. Results show that the secondary alteration associated with oil and gas accumulations above oil and gas field is predominantly magnetite mineralization, and that sulfur alteration occurs commonly at oil-water boundary and their products are generally pyrite and pyrrhotite, except for magnetite alteration which is closely related with hydrodynamical conditions in situ. The spherical magnetite grains of cauliflower microtexture on surface extracted from oil-bearing cores are secondary magnetite related with hydrocarbon microseepage and their diameters are usually less than 50 μm.

关键词： hydrocarbon microseepage magnetic mineralogy magnetic hysteresis loop thermal magnetic analysis reservoir petrophysics.

Gradient analysis of landscape spatial and temporal pattern changes in Beijing metropolitan area

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Science china(Technological Sciences) 2010年第S1期53卷 91-98页

作者： YANG YeTao1,ZHOU QiMing2,GONG JianYa3 & WANG YingYing4 1 Institute of Geophysics and Geomatics,china university of geosciences,wuhan 43.074,china 2 Department of Geography,Hong Kong Baptist university,Hong Kong 3 State Key Laboratory of Information Engineering in Surveying,Mapping and Remote Sensing,wuhan university,wuhan 43.074,china 4 Hubei Provincial Bureau of Meteorology,wuhan 43.074,china 1. Institute of Geophysics and Geomatics China University of Geosciences Wuhan 430074 China2. Department of Geography Hong Kong Baptist University Hong Kong China3. State Key Laboratory of Information Engineering in Surveying Mapping and Remote Sensing Wuhan University Wuhan 430074 China4. Hubei Provincial Bureau of Meteorology Wuhan 430074 China

The gradient based landscape metrics analysis is now widely used to study the landscape pattern changes in respond to the *** order to discover the trend of spatio-temporal changes in Beijing metropolitan area during the past 15 years,several landscape metrics are computed using a moving window along a 96.km long transect across Beijing metropolitan area from west to ***,the spatial extent of sub-landscape,which is determined by the moving window’s size,is profoundly *** results show that the metrics varies smoothly and regularly along the selected transect when the window size is greater than 6.km×6.km,and irregularly fluctuated for the smaller window size,that the spatial and temporal landscape characteristics of Beijing city match the hypothetical framework of spatio-temporal urban sprawl in the form of alternating processes of diffusion and coalescence well,and that some new trends of the urban sprawl style in Beijing metropolitan area,such as leap-frog manner,are also detected by the gradient landscape analysis.

关键词： gradient analysis landscape metrics spatio-temporal urban expansion multi-extent

A novel method of systematic error compensation for a position and orientation system

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Progress in Natural Science:Materials International 2008年第8期18卷 953-963页

作者： Xiuxiao Yuan* School of Remote Sensing and Information Engineering, wuhan university, wuhan 430079, china School of Remote Sensing and Information Engineering Wuhan University Wuhan 430079 China

A novel method is introduced for self-calibration and elimination of systematic errors for a position and orientation system (POS). The method uses a combined bundle block adjustment with POS data (named the POS-supported bundle block adjustment) without a calibration field. On the basis of delivering strict observation equations for POS data, the specific scheme of compensating the translation and drift systematic errors in a POS is given, and a prototype system WuCAPS is developed. The effects of eliminating POS systematic errors using the POS-supported bundle block adjustment for different ground control conditions are tested using two sets of actual aerial photos. The first set was taken over a flat region in the suburbs of the city of Yingkou in china and tested at a scale of 1:2500. The second set was taken over a high mountainous region in the desert region of Xinjiang in china and tested at a scale of 1:32,000. The empirical results verified that the POS systematic errors can be completely eliminated and the photo elements of exterior orientation obtained by the POS-supported bundle block adjustment can satisfy the requirements of aerial photogrammetric topographic mapping when four full ground control points (GCPs) are emplaced in the corners of the adjustment block for large-scale images of flat regions, but only one full GCP emplaced in the center of the adjustment block is needed for medium-small scale images of mountainous regions. This not only demonstrates the validity of the established mathematical model and the feasibility of the method proposed in this paper, but also avoids the use of a special calibration field. Therefore, it can simplify the existing POS operation rules and dramatically save on practical application costs, laying the theoretical foundation for widespread use of POS.

关键词： Position and orientation system (POS) Systematic error POS-supported bundle block adjustment Self-calibration Accuracy

Geothermal and fluid flowing simulation of ore-forming antimony deposits in Xikuangshan

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Science china Earth Sciences 2006年第8期49卷 862-871页

作者： YANG Ruiyan1,2, MA Dongsheng2, BAO Zhengyu3, PAN Jiayong2, CAO Shuanglin2 & XIA Fei2 1. School of Mathematics and Physics, china university of geosciences, wuhan 43.074, china 2. State Key Laboratory for Research of Mineral Deposits, Nanjing university, Nanjing 210093, china 3. Faculty of Earth Sciences, china university of geosciences, wuhan 43.074, china 1. School of Mathematics and Physics China University of Geosciences Wuhan 430074 China 2. State Key Laboratory for Research of Mineral Deposits Nanjing University Nanjing 210093 China 3. Faculty of Earth Sciences China University of Geosciences Wuhan 430074 China

The Xikuangshan Antimony Deposit located in the Mid-Hunan Basin, china, is the larg- est antimony deposit in the world. Based on the hydrogeological and geochemical data collected from four sections, Xikuangshan-Dajienao (AO), Xikuangshan-Dashengshan (BO), Xikuang- shan-Longshan (CO) and Dafengshan (DO) in the Basin, an advanced metallogenic model related to deep-cyclic meteoric water of Xikuangshan Antimony Deposit is put forward in this paper using a model of heat-gravity-driving fluid flow transportation. The simulation results show that the ore-forming fluid of the deposit mainly comes from the Dashengshan and Longshan areas where BO and CO sections are located if the overall basin keeps a constant atmospheric precipitation and infiltration rate during mineralization, and that the average transportation speed of the ore-forming fluids is about 0.2―0.4 m/a.

关键词： ore-forming fluid, numerical simulation, geothermal field, geofluid transport, Xikuangshan, antimony deposits.

COMPUTER VISION APPLIEDIN THE PRECISION CONTROL SYSTEM

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Chinese Journal of Mechanical Engineering 2002年第1期15卷 87-89页

作者： Zhang Qingying Logistics Engineering Department，wuhan university of Technology，wuhan 43006.，china Logistics Engineering Departiment Wuhan University of Technology Wuhan 430063

Computer vision and its application in the precision control system arediscussed. In the process of fabricating, the accuracy of the products should be controlledreasonably and completely. The precision should be kept and adjusted according to the information offeedback got from the measurement on-line or out-line in different procedures. Computer vision isone of the useful methods to do this. Computer vision and the image manipulation are presented, andbased on this, a n-dimensional vector to appraise on precision of machining is given.

关键词： Computer vision Measurement Precision Quality of products