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对数正态分布下边坡稳定性二元指标体系研究

山地学报 2005年第4期23卷 4442-4446页

作者：罗文强龚珏王亮清方云中国地质大学数理学院中国地质大学图书馆中国地质大学工程学院中国地质大学工程学院湖北武汉430074

安全系数不能考虑边坡系统中实际存在的不确定性,可靠性理论缺乏丰富的工程实践经验,因此,将工程实践经验丰富的安全系数与先进的可靠性理论相结合,建立传统安全系数与可靠性相耦合的二元评价体系具有重要的理论意义和应用价值。设安全... 详细信息

安全系数不能考虑边坡系统中实际存在的不确定性,可靠性理论缺乏丰富的工程实践经验,因此,将工程实践经验丰富的安全系数与先进的可靠性理论相结合,建立传统安全系数与可靠性相耦合的二元评价体系具有重要的理论意义和应用价值。设安全系数服从对数正态分布,取系列的最大可能安全系数(中值安全系数)和变异系数,计算得到最大可能安全系数及在不同变异系数下的破坏概率Pf。从而可由最大可能安全系数和可靠性(R=1-Pf)共同度量边坡的稳定性。将最大可能安全系数与边坡可靠性相乘,对最大可能安全系数进行折减,得到边坡可靠的安全系数。根据折减后安全系数的极限状态,可计算出不同最大可能安全系数的临界变异系数和临界破坏概率。根据不同最大可能安全系数及它的临界破坏概率,绘出边坡稳定性分区图,并建立安全系数和破坏概率相结合的边坡稳定性判别的二元指标体系。文中提供了小样本条件下,利用3.方差原理估计参数方差的计算方法,并给出了边坡稳定性二元指标体系的研究实例。

关键词：边坡稳定性最大可能安全系数对数正态分布可靠性二元指标体系

Lead Isotope and Rock Geochemistry of Zaibian Mafic-Ultramafic Rock,Southeast Guizhou Province,china

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矿物学报 2009年第S1期29卷 70-70页

作者： LIU Yong-kun1,ZHOU Jia-xi2,HUANG Zhi-long2,WANG Jing-song1,YANG De-zhi1,3.DING wei2,CHEN Yuan-xing1,BAO Guang-ping2(1. The 102 Geological Team,Guizhou Bureau of Exploration and Development of Geology and Mineral Resources,Zunyi 563.03.china 2. State key Laboratory of Ore Deposits Geochemistry,Institute of Geochemistry,Chinese Academy of Science,Guiyang 550002,china 3. china university of geosciences({3.) ,{3. 430074,china)

The Zaibian mafic-ultramafic rock is located in the transitional zone of the Yangtze craton and south china fold system,where is the southwest of Jiangnan orogenic belt(Zeng et al.,2003.Wang et al.,in press).

关键词： Pb rock Lead Isotope and Rock Geochemistry of Zaibian Mafic-Ultramafic Rock,Southeast Guizhou Province,china

Sulfur Isotopes Geochemistry of the Nage Cu-Pb Polymetallic Deposit,Southeast Guizhou Province,china

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矿物学报 2009年第S1期29卷 128-128页

作者： LONG Xuan-lin1,ZHOU Jia-xi2,HUANG Zhi-long2,WANG Jing-song1,YANG De-zhi1,3.FAN Liang-wu2,BAO Guang-ping2,LIU Yong-kun1(1. The 102 Geological Team,Guizhou Bureau of Exploration and Development of Geology and Mineral Resources,Zunyi 563.03.china 2. State key Laboratory of Ore Deposits Geochemistry,Institute of Geochemistry,Chinese Academy of Science,Guiyang 550002,china 3. china university of geosciences({3.) ,{3. 430074,china) evidence.

The Nage Cu-Pb polymetallic deposit is located in the transitional zone of the Yangtze craton and cathaysia,that is the southwest of Jiangnan orogenic belt. The mainly strata are Wentong formation of Mesoproterozoic Sibo group and the Jialu formation(Qbj) ,Wuye formation(Qbw) ,Fanzhao formation(Qbf) and Gongdong formation(Qbg) of the Neoproterozoic Qingbaikou System Xiajiang group.

关键词： Pb Sulfur Isotopes Geochemistry of the Nage Cu-Pb Polymetallic Deposit,Southeast Guizhou Province,china Cu

Exsolution of ilmenite and Cr-Ti magnetite from olivine of garnet-wehrlite

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Science china Earth Sciences 2005年第9期48卷 1368-1376页

作者： LIU Xiangwen1,2, JIN Zhenmin1,3. QU Jing2 & WANG Lu2 1. State Key Laboratory of Geological Processes and Mineral Resources, china university of geosciences,{3., china 2. Graduate School of china university of geosciences,{3., china 3. Faculty of Earth Sciences, china university of geosciences,{3., china 1. State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences 430074 Wuhan China 2. Graduate School of china university of geosciences 430074 Wuhan China 3. Faculty of Earth Sciences China University of Geosciences 430074 Wuhan China

Exsolution of rod-like ilmenite (Ilm) and Cr-Ti magnetite (Mt) have been found in olivine of garnet-wehrlite from the core of Chinese Continental Sciences Drilling (CCSD). Their composition, morphology, crystal structure and their topotaxies with host olivine have been studied in detail by the transmission electron microscopy (TEM) and electron probe microanaly- sis (EPMA) technique. It shows that rod-like Ilm exsolution reported in this paper has similar characteristic with that of Alpe Arami olivine, while Cr-Ti magnetite exsolution mentioned in this paper has large discrepancy with chromite exsolution in Alpe Arami olivine. These observations suggest that both of the exsolutions found in this paper should be solid solution phases in β-olivine at their first period, then experiencing decomposition of solid solution and therefore forming Ilm and Cr-Ti magnetite exsolution with the pressure decreasing. So, this garnet-wehrlite perhaps had been ever located in mantle transition zone with a minimum depth of 3.0 km.

关键词： garnet-wehrlite, ilmenite, magnetite, exsolution, CCSD.

Electron microscopy study of the sakhaite from endogenous borate deposit in Hunan, china

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Science china Earth Sciences 2004年第3期47卷 232-238页

作者： LIU Xiangwen1,2, YANG Guangming2, ZOU Huamin3. QU Jing1 & ZHAO Wenxia4 1. Graduate School, china university of geosciences,{3., china 2. Test Center, china university of geosciences,{3., china 3. Physics and Technology College, wuhan university, wuhan 43.072, china 4. Test Center, Zhongshan university, Guangzhou 510275, china china Univ Geosci Grad Sch Wuhan 430074 Peoples R China china Univ Geosci Test Ctr Wuhan 430074 Peoples R China wuhan Univ Phys & Technol Coll Wuhan 430072 Peoples R China Zhongshan Univ Test Ctr Guangzhou 510275 Peoples R China

Sakhaite specimens from an endogenous borate deposit in Hunan Province, china have been studied in detail by means of transmission electron microscopy (TEM). The selected area electron diffraction (SAED) patterns obtained with different crystal zone axes show that the crystal system is cubic, with a = 1.463.nm. The convergent beam electron diffraction (CBED) patterns indicate that the point group and space group of sakhaite is m3. and Fd3., respec-tively. The space group of synthetic sakhaite determined by Chichagov (1974) is F413.. The possible reasons why the space groups of the natural and the synthetic sakhaites are different are discussed.

关键词： sakhaite, space group, convergent beam electron diffraction (CBED).

Analytical method of Cr stable isotope and its application to water pollution survey

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Chinese Science Bulletin 2010年第7期55卷 664-669页

作者： GAO YongJuan 1,2,3.MA Teng 4,5,LING WenLi 1,2,LIU CunFu 4,5 & LI Li 4,5 1Faculty of Earth Science,china university of geosciences,{3. 430074,china 2State Key Laboratory of Geological Processes and Mineral Resources,china university of geosciences,{3. 430074,china 3.Graduate School,china university of geosciences,{3. 430074,china 4 Biogeological and Environmental Geology Laboratory of Ministry of Education(china university of geosciences) ,{3. 430074,china 5 Sino-Hungary Joint Laboratory of Environmental Sciences and Health,china university of geosciences,{3. 430074,china Faculty of Earth Science China University of Geosciences Wuhan 430074 China State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Wuhan 430074 China Graduate School China University of Geosciences Wuhan 430074 China Biogeological and Environmental Geology Laboratory of Ministry of Education (china university of geosciences) Wuhan 430074 China Sino-Hungary Joint Laboratory of Environmental Sciences and Health China University of Geosciences Wuhan 430074 China

High Cr(VI) concentration is a potential serious risk to environment and ecologic ***,it is essential to effectively monitor Cr contamination in water systems and scientifically evaluate its evolution trend.A new method of in-situ tracer technique by Cr isotopic analysis for quantitatively estimating Cr-contamination and its regional evolution in natural waters as well as a case application are reported in this *** on documented literatures,an experimental procedure for chemical separation and purification of Cr in water samples and its analytical method for Cr isotopic measurement by thermal ionization mass spectrometry(TIMS) are *** samples collected around a chemical factory in Hubei Province were analyzed by this *** samples showδ53.r values ranging from-1.7‰to 7.3.and an elevating trend with an increasing in distance from the sampling site to pollution source.A functional correlation following Rayleigh fractionation law was established between sample'sδ53.r value and its extent of Cr *** study suggests that Cr isotopic analysis is an effective method to reveal the spatial distribution and its evolution trend of Cr contamination in the regional water *** is thus helpful to assessing the self-purifying ability of local water system according to Cr isotopic fractionation.

关键词：铬(VI) 水污染调查稳定同位素应用同位素分析供水系统演变趋势示踪技术

Evolutionary patterns of Productida (Brachiopoda) morphology during the Permian in South china

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Science china Earth Sciences 2008年第11期51卷 1589-1600页

作者： ZHANG Yang1 & HE WeiHong1,2 1 Faculty of Earth Sciences, china university of geosciences,{3., china 2 Key Laboratory of Biogeology and Environmental Geology of Ministry of Education, china university of geosciences,{3., china 1. Faculty of Earth Sciences China University of Geosciences Wuhan 430074 China 2. Key Laboratory of Biogeology and Environmental Geology of Ministry of Education China University of Geosciences Wuhan 430074 China

The evolutionary patterns of Productida (brachiopod) morphology throughout the Permian show that while the percentage proportion of Productida (brachiopod) with strongly concentric and radial ornamentation declined from the Cisuralian to the Guadalupian, and then increased towards the Changhsingian via Wuchiapingian, the percentage proportion of Productida (brachiopod) with fine concentric and radial ornamentation distinctly increased from the Cisuralian to the Guadalupian, slightly declined towards the Wuchiapingian, and then increased towards the Changhsingian. From the Cisuralian to the Changhsingian, the percentage proportion of brachiopods with spinose ornamentation shows a persistent declining trend. The shell size generally indicates a miniaturization trend at species level during the Wuchiapingian to Changhsingian (including the transitional bed). These evolutionary patterns of brachiopod ornamentation and size are possibly related to the anoxia, food shortage, sea-level fluctuation, and change of substrate in the Permian (including the Permian-Triassic transitional interval) in South china.

关键词： brachiopod ornamentation size Permian South china

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 university of geosciences,Beijing 100083.china 2. Faculty of Earth Sciences,china university of geosciences,wuhan 430074,china 3. Department of Earth Sciences,Jilin university,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.

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,{3., china 2. State Key Laboratory for Research of Mineral Deposits, Nanjing university, Nanjing 210093. china 3. Faculty of Earth Sciences, china university of geosciences,{3., 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.