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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,{2. university of geosciences, wuhan 430074,{2. 2. Test Center,{2. university of geosciences, wuhan 430074,{2. 3. Physics and Technology College, {12. university, {12. 430072.{2. 4. Test Center, Zhongshan university, Guangzhou 5102.5,{2. graduate school China University of Geosciences Wuhan 430074 China Test Center China University of Geosciences Wuhan 430074 China Physics and Technology College Wuhan University Wuhan 430072 China Test Center Zhongshan University Guangzhou 510275 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 m3m and Fd3m, respec-tively. The space group of synthetic sakhaite determined by Chichagov (1974) is F4132. 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 {2.,wuhan 430074,china 2.tate Key Laboratory of Geological Processes and Mineral Resources,china university of {2.,wuhan 430074,china 3 {12. school,china university of {2.,wuhan 430074,china 4 Biogeological and Environmental Geology Laboratory of Ministry of Education(china university of {2.) ,wuhan 430074,china 5 Sino-Hungary Joint Laboratory of Environmental Sciences and Health,china university of {2.,wuhan 430074,china Faculty of Earth Science China University of Geosciences Wuhan China State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Wuhan China graduate school China University of Geosciences Wuhan China Biogeological and Environmental Geology Laboratory of Ministry of Education (china university of {2.) Wuhan China Sino-Hungary Joint Laboratory of Environmental Sciences and Health China University of Geosciences Wuhan 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 showδ53Cr 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'sδ53Cr 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

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 {2. of geosciences, wuhan 430074, china 2. State Key Laboratory for Research of Mineral Deposits, Nanjing {2., Nanjing 2.0093, china 3. Faculty of Earth Sciences, china {2. of geosciences, wuhan 430074, china school of Mathematics and Physics China University of Geosciences Wuhan China State Key Laboratory for Research of Mineral Deposits Nanjing University Nanjing 210093 China Faculty of Earth Sciences China University of Geosciences Wuhan 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.

Evolution Mechanism of Slip Zone Under Fluctuation of Ground Water Table of Landslide

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地学前缘 2009年第S1期16卷 55-56页

作者： Bo Chai~1,Kunlong Yin~2.1.school of Environmental Studies,china {2. of geosciences(wuhan),wuhan 430074,china. 2.Engineering Faculty,china {2. of geosciences(wuhan),wuhan 430074,china

The fluctuation of ground water table of landslide caused by the changing of rain fall and reservoir water level leads the slip zone to possess the complicated deformation features of stepped and *** role of the groun... 详细信息

关键词： groundwater fluctuation slip zone landslide

Study on iron-based diamond bit by DC-electroplating method

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金刚石与磨料磨具工程 2008年第S1期28卷 186-190页

作者： Tian Yongchang~1 Yang Zhan~2.(1.graduate school,{2. university of geosciences,wuhan 430074,{2.) (2.school of Mechanical and Electronic Engineering,{2. university of geosciences,wuhan 430074,{2.)

Iron-plating technology used for restoration of axis parts was applied to the manufacture of diamond bits in this *** technology for electroplating diamond bit of iron matrix was mastered through repeated experiments and *** productive practice indicated that the DC-electroplated iron matrix of diamond bit has high hardness and good diamond exposure ability;the drilling rate of electroplated iron-based diamond bit was 2.m/h when drilling in grade 9 granite and bit life can reach 44 m,which can satisfy the drilling production requirements.

关键词： iron-based matrix asymmetric AC/DC electroplating diamond exposure

Accumulation characteristics and the main controlling factors of Lunnan multilayer oil province,Tarim Basin,china

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Science china Earth Sciences 2008年第S1期51卷 65-76页

作者： YANG HaiJun1 ,2.HAN JianFa 1,2.1Resources school of china {2. of geosciences,wuhan 430074,china 2.esearch Institutes of Tarim Oilfield Company,Petrochina,Korla 841000,china Resources school of china {2. of geosciences Wuhan China Research Institutes of Tarim Oilfield Company PetroChina Korla China

Lunnan region is a large-scale paleohigh with many coexisting oil and gas bearing *** present, about 2.billions tons of proved,probable and possible oil and gas reverses have been proved *** oil and gas bearing series have been found in the Ordovician,Carboniferous,Triassic and Jurassic of Lunnan region,they all bear the characteristics of large-scale multilayer oil-gas *** is the main reservoir series where over 0.8 billion tons of oil geologic reserves were discovered,and a super large-scale marine carbonate oil and gas field has *** space of the carbonate reservoirs is mainly composed of dissolved hole,dissolved pore and fracture in Lunnan paleo-burial ***, dissolved holes are widely distributed among *** developments are mainly controlled by karstification and tectonic *** to the similar geochemical characters,the Ordovician,Carboniferous,Triassic and Jurassic oil and gas reservoirs present the same oil source rock of Mid-Upper Ordovician,the latter except Ordovician are mostly of secondary oil and gas reservoirs migrated vertically by faults during the process of multiple phase tectonic movement,adjustment and reconstruction. Lunnan composite oil and gas accumulation region is situated in the vicinity of large-scale hydrocarbon generation depressions in three directions,ample oil and gas from hydrocarbon generation depressions supplied the adjacent oil and gas reservoirs ***,the succeed paleohigh is the long-term hydrocarbon accumulation region,which is favor for the formations of high quality reservoirs,fault systems and huge-scale composite oil and gas accumulation.

关键词： multilayer oil and gas reservoirs paleohigh Ordovician Lunnan region Tarim Basin

Entropy-Based Approach to Remove Redundant Monitoring Wells from Regional-Scale Groundwater Network

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Journal of china university of {2. 2002年第3期13卷 266-273页

作者： Chen Zhihua Engineering Faculty, china university of {2., wuhan 430074 Jing Juanli graduate school, china university of {2., wuhan 430074 Chen Gang Engineering Faculty, china university of {2., wuhan 430074 Engineering Faculty China University of Geosciences Wuhan 430074 graduate school China University of Geosciences Wuhan 430074

An entropy-based approach is applied to identify redundant wells in thenetwork. In the process of this research, groundwater-monitoring network is considered as acommunication system with a capability to transfer information, and monitoring wells are taken asinformation receivers. The concepts of entropy and mutual information are then applied to measurethe information content of individual monitoring well and information relationship betweenmonitoring well pairs. The efficiency of information transfer among monitoring wells is the basis tojudge the redundancy in the network. And the capacity of the monitoring wells to provideinformation on groundwater is the point of evaluation to identify redundant monitoring wells. Thisapproach is demonstrated using the data from a regional-scale ground-water network in Hebei plain,china The result shows that the entropy-based method is recommendable in optimizing groundwaternetworks, especially for those within media of higher heterogeneities and ani-sotropies.

关键词： entropy groundwater monitoring network optimize redundant

Improved Approaches Coupling the Method on Discharge Allocation and“High Kv in Wellblock”for Simulating Multiaquifer Wells

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地学前缘 2009年第S1期16卷 23-24页

作者： Quanrong Wang~1,Zhonghua Tang~1,Lijuan Zhai~2.1.school of Environmental Studies,china {2. of geosciences(wuhan),wuhan 430074,china. 2.school of Foreign Language,china {2. of geosciences(wuhan),wuhan 430074,china

The mathematic models to simulate the multiaquifer well using the discharge allocation based on explicit transmissivity-weighted or the implicit transmissivity and the hydraulic gradient(TJ method),can not describe the actual well,especially with vertical flow along the *** order to improve the accuracy of the results,two improved approaches are established,by coupling the ideas of"High Kv in Wellblock"into the aforementioned methods on discharge allocation to consider the vertical flow

关键词： multiaquifer wells discharge allocation high conductivity

Indian Ocean-MORB-type isotopic signature of Yushigou ophiolite in North Qilian Mountains and its implications

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Science china Earth Sciences 2006年第6期49卷 561-572页

作者： HOU Qingye1,2. ZHAO Zhidan1,2. ZHANG Hongfei3, ZHANG Benren3 & CHEN Yuelong2.1. State Key Laboratory of Geological Processes and Mineral Resources, china university of {2., Beijing 100083, china 2. school of Earth Science and Mineral Resources, china university of {2., Beijing 100083, china 3. Faculty of Earth Sciences, china university of {2.,{12., china State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Beijing China school of Earth Science and Mineral Resources China University of Geosciences Beijing China Faculty of Earth Sciences China University of Geosciences Wuhan China

In order to explore the disputed issue concerning the tectonic affinity ofthe ancient ocean mantle of North Qilian Mountains (NQM), geochemical and Sr, Nd, Pb isotopiccompositions of pillow basalts of the Yushigou Ophiolite (YSGO) suite from NQM have been analyzedsystematically. The pillow basalts exhibit tholeiitic characteristics, with flatchondrite-normalized REE patterns ((La/Yb)_N = 0.98—1.2.). They display no Nb, Ta, Zr, Hf negativeanomalies, and show MORB features in 2.b-Zr/4-Y and Ti/100-Zr-YX3 tectonic discrimination *** results indicate that the Yushigou ophiolite is most likely to be formed in a mid-ocean ridgeor mature back-arc basin. Their isotopic data show a relatively broad and enriched ^(87)Sr/^(86)Sr(0.70509 — 0.70700), restricted ^(143)Nd/^(144)Nd (0.512.55-0.512.78). Pb isotopes are in the rangeof ^(2.6)Pb/^(2.4)Pb (18.054-2..562., ^(2.7)Pb/^(2.4)Pb (15.537-15.743) and ^(2.8)Pb/^(2.4)Pb(38.068-38.530). These isotopic data imply that the basalts originated from the depleted mantle(DMM), with the involvement of enriched mantle components (mainly EMII). Geochemical comparisonsbetween the basalts in YSGO and the MORB-type basalts of ophiolite suites occurring in the knownancient Tethyan tectonic domain indicate that the ancient oceanic mantle represented by YSGO suiteforming in early Paleozoic in the North Qilian Moutains is very similar to the Tethyan mantle inboth trace elements and isotopic compositions. The North Qilian Mountains should be a part of theTethyan tectonic domain in early Paleozoic. This further implies that the Tethyan tectonic domaincan be deduced to early Paleozoic in the study area, which will be helpful to discussing thetectonic affinity and evolution of the North Qilian Mountains.

关键词： geochemistry, Indian Ocean-MORB-type isotopic signatures, Tethyan tectonic domain, Yushigou ophiolite, North Qilian Mountains.