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Sedimentary Basins in the Western White Nile, Sudan, as Indicated by a Gravity survey

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Journal of china University of Geosciences 2002年第3期13卷 289-296页

作者： Mohammed I A Wang Jiaying Liu Tianyou Department of Geophysics, china University of Geosciences, Wuhan 430074 Farwa A G Department of Geology, Faculty of Science, University of Khartoum, Sudan Department of Geophysics China University of Geosciences Wuhan 430074 Department of Geology Faculty of Science University of Khartoum Sudan

An academic geophysical research as a regional gravity survey was made during1994 in the Western White Nile to infer the shallow crustal structures in the area. The result ofthe survey was compiled as a Bouguer anomaly map with a contour interval of 2 X 10^(-5)m/s^2. It isfound that the negative residual anomalies are related to the Upper Cretaceous sediments (NubianSandstone Formation) filling all depressions in the Basement complex surface while the positiveresidual anomalies are attributed to the relatively shallow or outcropping Basement rocks and thesteep gravity gradients are resulting from the sharp contacts between the sedimentary infill and theBasement rocks. To define the geological structures in the area, 9 profiles were studied. For eachof the profiles, measured and computed Bouguer gravity anomalies, crustal density model, subsurfacegeology evaluation were performed. A G-model computer program was applied in the gravity modeling,which is based on the line-integral method of gravity computation. A geological/structural map wasproposed showing inferred sedimentary basins, faulting troughs and uplifted Basement block andtectonic trends. The basins are believed to be fault-controlled which developed by extensionaltectonics (pull-apart mechanism). As for the mechanism and cause of faulting, the area is consideredas a part of the Central Sudan rift system which had been subjected to several tectonic eventssince Early Cambrian to Tertiary times which resulted in the formation of several fracture systemsassociated with block subsidence, rifting and basin formation.

关键词： bouguer anomaly residual anomaly basin fault pull-apart rift-system

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Distribution of groundwater salinity and formation mechanism of fresh groundwater in an arid desert transition zone

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Journal of Groundwater Science and Engineering 2015年第3期3卷 268-279页

作者： ZHOU Li-ling CHENG Zhe DUAN Lei WANG Wen-ke Geology Environment Monitoring Institute of Zhejiang Province HangzhouZhejiang 310007China Beijing Geotechnical and Investigation Engineering Institute Beijing 100083China School of Environmental Science and Engineering Chang’an UniversityXi’anShaanxi 710054China

This study reviews the distribution of groundwater salinity in an arid desert transition zone. By combining field experiments and computer simulation models we make a comprehensive analysis of the formation mechanism of fresh groundwater in relation to the paleogeographic conditions of lithofacies, the geochemical characteristics of the aquifer media, salt deliverability in the vadose zone and prevailing hydrodynamic conditions. The results demonstrate that(1) the lacustrine facies deposition stratum of the Huanhe formation in the Cretaceous system provides a brackish-salt groundwater environment;(2) the average salinity of parent rocks are approximately 440 mg/kg and 4 371 mg/kg in the Quaternary eolian sand and the Cretaceous Huanhe formation respectively, suggesting that parent rocks are the principal controlling factor in the distribution of groundwater quality given that mineral and chemical composition of the eolian sand is simpler than that of the Huanhe formation;(3) average groundwater flow rates are approximately 0.25 m/d and 0.1 m/d in eolian sand and Huanhe formation aquifers respectively, indicating that hydrodynamic conditions play an important role in driving in the formation and evolution of fresh groundwater;(4) The salinity deliverability in the vadose zone overlying the aeolian sand and Huanhe formation aquifers are approximately 15.97 mg/L and 220.42 mg/L respectively, signifying that the combination of lithology and salt content of vadose zone, rainfall infiltration, evapotranspiration and concentration heavily influence the formation, distribution and evolution of groundwater quality. This study can provide a scientific basis for the sustainable development and utilization of groundwater resources in arid areas.

关键词： Desert transition zone Distribution of groundwater salinity Formation mechanism of fresh groundwater Arid area

Mineralogy and Mineral Chemistry of the Cretaceous Duolong Gold-Rich Porphyry Copper Deposit in the Bangongco Arc,Northern Tibet

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Mineralogy and Mineral Chemistry of the Cretaceous Duolong G...

中国科学院地质与地球物理研究所2012年度（第12届）学术年会

作者： Jinxiang LI Guangming LI Kezhang QIN Bo XIAO Lei CHEN Junxing ZHAO Key laboratory of Mineral Resources Institute of Geology and GeophysicsChinese Academy of Sciences

The Early Cretaceous Duolong gold-rich porphyry copper deposit is a newly discovered deposit with proven 5.38 Mt Cu resources of 0.72% Cu and 411 gold of 0.23 g t in northern *** porphyry and quartz diorite porphyrite are the main ore-bearing porphyries.A wide range of hydrothermal alteration associated with these porphyries is divided into potassic,argillic and propylitic zones from the ore-bearing porphyry center outward and *** the hydrothermal alteration zones,secondary albite(91.5-99.7% Ab) occurs along the rim of plagioclase phenocryst and *** K-feldspar(75.1-96.9% Or) replaces plagioclase phenocryst and matrix or occurs in *** occurs mainly as matrix and veinlet in addition to phenocryst in the potassic *** biotite are Mg-rich and formed under a highly oxidized condition at temperatures ranging from 400℃ to 430℃ .All the biotites are absent in F,and have high Cl content(0.19-0.26% ),with log(X/X) values of -2.74 to -2.88 and IV(Cl) values of—3.48 to—3.35,suggesting a significant role of chloride complexes (CuCl and AuCl) in transporting and precipitating copper and *** are present in all alteration zones and correspond mainly to *** have similar Fe/(Fe+Mg),Mn/(Mn+Mg) ratios,and a formation temperature range of 280-360℃ .However,the formation temperature of chlorite in the quartzgypsurn -carbonate-chlorite vein is between 190℃ and 220℃ ,indicating that it may have resulted from a later stage of hydrothermal ***/Fe ratios of chlorites have negative correlation with AP,suggesting oxygen fugacity of fluids increases with decreasing *** mineral inclusions in the biotite phenocrysts show high SO content(0.44-0.82% ) and high Cl content(1-1.37% ),indicating the host magma had a high oxidation state and was enriched in S and *** highest Cl content of apatite in the propylitic zone may have resulted from pressure decrease,and the lowest Cl content of apatite in t

关键词： Bangongco arc Duolong gold-rich porphyry copper deposit mineral chemistry mineralogy

Influence of dip directions on the main deformation region of layered rock around tunnels

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Influence of dip directions on the main deformation region o...

中国科学院地质与地球物理研究所2014年度（第14届）学术年会

作者： Zhen-dong Cui Da-an Liu Fa-quan Wu Key laboratory of Engineering Geomechanics Institute of Geology and GeophysicsChinese Academy of Sciences

The influence of dip directions on the main deformation region of layered rock around tunnel is studied using a 3D distinct element code called *** learn that the main deformation regions around tunnels are regularly changeful along with different intersection angles between dip direction and advancing direction of the *** specific deformation regions can be anticipated based on detailed engineering geological survey before tunnel ***,the common deformation pattern around tunnels is found to be structural deformation including bending and slipping of layered *** main deformation region is prone to occur at the region where the normal direction of rock layer points to the inside of tunnel because the minimum tensile strength of bedding plane appears on this region and rock bending is generally easier than rock *** understanding of the main deformation regions around tunnels provides critical information for selecting the route of a tunnel,forecasting the main deformation region and designing an efficient support system.

关键词： Dip direction Main deformation region Intersection angle Advancing direction of tunnels Layered rock

Cooling and exhumation of the Late Cretaceous Laojunshan granites in southeast Yunnan Province， china: constraints from fission-track thermochronology and tectonic implications

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Journal of Earth Science 2022年

作者： Fang Li Hao Bai Ye Fang Da Zhang Ganguo Wu Wei Xue Chaoyang Que Xinming Zhang Xiaolong He Bojie Hu Fujian Earthquake Agency china University of Geosciences (Beijing) Zijin Mining Group Co.， Ltd.

The Song Chay Dome in southeastern Yunnan Province， china， is intruded by the Late Cretaceous Laojunshan granites. New apatite and zircon fission-track data for the Laojunshan granites allow us to reconstruct the exhumation history of the Song Chay Dome. The fission-track dating indicates that the Laojunshan granites experienced four main stages of rapid cooling and exhumation at 75–63， 53–43， 31–20， and 12–4 Ma. The first stage was related to the thermal equilibration with surrounding rocks after magma emplacement. The rapid cooling and exhumation at 53–43 Ma were caused by normal faulting in the late Mesozoic–early Cenozoic extensional setting of southwestern South china， which resulted in the Laojunshan granites and Song Chay Dome being exhumed in the footwall of faults. The third stage (31–20 Ma) was the result of southeastward extrusion of the Tibetan Plateau and sinistral strike-slip movement on the NW–SE-trending Nanwenhe and Maguan–Dulong faults. The 31 Ma representing the beginning of the interaction between the Tethyan Himalayan tectonic domain and the South china Block. The final stage was mainly due to activity on the Nanwenhe Fault to the north of the Laojunshan granites， caused by lateral extrusion of the southeastern Tibetan Plateau since ca. 15Ma. These cooling and exhumation events since the Late Cretaceous indicate that the Song Chay Dome and southwestern South china Block have been affected by the Himalayan Orogeny since the Oligocene.

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Groundwater Environmental Impact of Jiupansi Tunnel

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Meteorological and Environmental Research 2020年第5期11卷 167-173页

作者： Zilong WANG Haoyu WU Huazhang LIN Hao LIU City College Southwest University of Science and TechnologyMianyang 621000China Sichuan Highway Planning Survey and Design Research Institute Co.Ltd.Chengdu 610059China china Three Gorges Construction Management Co. Ltd.Chengdu 610000China

In tunnel construction,groundwater is often dried up,and vegetation around the tunnel is exhausted due to excessive water *** on the requirement of environmental sustainable development,it is of great practical significance to carry out in-depth research on this *** Jiupansi Tunnel crossing Xichang-Shangri-La Expressway as an example,on the basis of engineering geological investigation,the types of groundwater flow are studied,and the ways of groundwater discharge and recharge are ***,the surface runoff,underground catchment and water inflow caused by the construction are *** results show that during the construction period of the tunnel,the maximum water inflow is 6041 m 3/d,and the normal water inflow is 2041 m 3/d;the groundwater level is lowered,and the maximum influence radius of the funnel is 157 *** the point of view of groundwater and ecological environment impact,it is reasonable and feasible to construct tunnels under the condition of strengthening advance prediction,which will not cause larger groundwater environmental problems and have less impact on nearby residents and upper ecology.

关键词： Tunnel Groundwater Water inrush Runoff

Semi-clathrate hydrate based carbon dioxide capture and separation techniques

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Frontiers of Environmental Science & Engineering 2023年第12期17卷 1-29页

作者： Lijuan Gu Hailong Lu Beijing International Center for Gas Hydrate School of Earth and Space SciencesPeking UniversityBeijing 100871China National Engineering Research Center for Gas Hydrate Exploration and Development Guangzhou 511466China

CO_(2)is considered as the main contributor to global warming,and hydrate enclathration is an efficient way for carbon capture and separation(CCS).Semi-clathrate hydrate(SCH)is a type of clathrate hydrate capable of encaging CO_(2)molecules under mild temperature and pressure *** has numerous unique advantages,including high thermal stability,selective absorption of gas molecules with proper size and recyclable,making it a promising candidate for *** SCH based CCS technology is in the developing stage and great efforts have to be conducted to improve the performance that is determined by their thermodynamical and structural *** review summarizes and compares the thermodynamic and structural properties of SCH and quaternary salt hydrates with gas mixtures to be captured and *** on the description of the physical properties of SCH and hydrate of quaternary salts with gas mixture,the CO_(2)capture and separation from fuel gas,flue gas and biogas with SCH are *** review focuses on the use of tetra-nbutyl ammonium halide and tetra-n-butyl phosphonium halide,which are the current application *** review aims to provide guidance for the future applications of SCH.

关键词： Semi-clathrate hydrate Tetra-n-butyl ammonium halide Tetra-n-butyl phosphonium halide Structure Thermodynamical properties CO_(2) capture and separation

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Synthesis and Characterization of U（VI） and Th（IV） complexes via tris（2-carboxyethyl） isocyanurate

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Synthesis and Characterization of U（VI） and Th（IV） compl...

中国化学会第九届全国无机化学学术会议

作者： Lingling Liang Ronglan Zhang Jianshe Zhao Chiyang Liu College of Chemistry & Material Science Northwest UniversityKey Laboratory of Synthetic and Natural Functional Molecule Chemistry of Ministry of EducationShaanxi Key Laboratory of Physico-Inorganic chemistry Department of Geology Northwest University

As a flexible tripodal ligand with highly flexible arms,tris（2-carboxyethyl）isocyanurate（H3tci）has been widely employed in recent years in coordination chemistry,which holds great flexibility because of the presence of a–CH2CH2–spacer between the central ring and the carboxylate that can bend to meet the requirement of the coordination conformation,and secondary functional *** of tris（2-carboxyethyl）isocyanurate（H3tci）with uranyl nitrate and thorium nitrate in hydrothermal conditions respectively,yields two novel actinide *** 1,[（UO2）2（H2O）4]0.5（tci）2（UO2）4（OH）4 contained two distinct UO22+coordination *** uranium atoms linked throughμ3-OH respectively,results in the edge-sharing ***,the U-O clusters layer structure linked through other eight-coordinated uranyl unions,resulting in a porous structure in the bc *** to the flexible parts（-CH2CH2-）of the ligand,the carboxylate arms showed the syn-syn-syn and syn-syn-anti bridging *** 2,[Th3（tci）2O2（OH）2（H2O）3]n,contained nine-fold coodinated Th（IV）centers with a monocapped square antiprismatic *** hexamers"Th6（μ3-O）4（μ3-OH）4"units are linked through the carboxylate groups,showing a three-dimensional structures.

关键词： flexible ligand uranium complex thorium complex crystal structure

Composite Metallogenic Systems in the Weihai Area of Shandong and Evolution of Continental Dynamic Regimes

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Acta Geologica Sinica(English Edition) 2007年第2期81卷 312-321页

作者： SUN Zhongshi WANG Peifu DENG Jun WANG Qingfei WANG Jianping MU Taisheng SUN Li FAN Siqi YE Songqing LIU Zhenghong CUI Shuxue Department of Earth Science Jilin University Changchun Jilin 136001 Xiadian Gold Mine Zhaoyuan Shandong 265418 Department of Geosciences and Mineral Resources China University of Geosciences Beijing 100083

Based on 9 sheets of 1：50,000-scale regional geological survey and guided by the theory of metallogenic systems and integrated analyses of the structural and metallogenic features, this paper hereby puts forward the composite metallogenic systems of the Weihai area, Shandong Province, aiming at solving the problems on the origins and ore-controlling structures of the numerous deposits in the area. Its scientific significance is reflected in the following three aspects：（1） The basic features of the composite metallogenic systems can be recognized, which consist of two types： the Proterozoic metamorphic-hydrothermal metallogenic system and the Mesozoic magmatic-hydrothermal metallogenic system （i.e. the Indosinian-early Yanshanian contact metasomatic metallogenic series and the mid-late Yanshanian magmatic-hydrothermal metallogenic series）. The two series display arcuate and NW-right lateral arrangements and a N-S parallel zonal distribution respectively, with the corresponding mineral assemblages being Au＋Ag＋Pb＋Zn, etc.; and Cu＋Mo＋Fe, Au＋Ag＋Cu＋Pb- Zn＋Mo＋Co-Ni＋sulfides＋silicides＋K-feldspar, etc. （2） The composite metallogenic systems may be used to interpret the complicated genetic relations of the deposits. Through analyses of the relations between the three main metallogenic intervals and their corresponding source rock series （the Jingshan and Rongcheng groups; the Wendong super-unit and the early-middle Yanshanian Weideshan super-unit; and the mid-late Yanshanian Weideshan and Laoshan super-units） as well as a case study of the Fanjiabu gold deposit, we have distinguished the consanguinity between the contact metasomatic （skarn-type） metallogenic series and the magmatic-hydrothermal metallogenic series as well as the noncognate superposition between the two and the metamorphic-hydrothermal metallogenic system. （3） The composite metallogenic systems are easily related to the evolution of continental dynamic regimes. The formation of the metamorphic-hydrothermal me

关键词： composite metallogenic system continental dynamic regime Weihai Shandong Province

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