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Shear mechanical properties and frictional sliding responses of rough joint surfaces under dynamic normal displacement conditions

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Journal of Central South University 2024年第7期31卷 2393-2410页

作者： ZHU Qiang YIN Qian TAO Zhi-gang HE Man-chao ZHENG Bo-wen JING Hong-wen REN Shu-lin ZHANG Qiang MENG Bo BAI Dong-feng WU Sai-sai WU Jiang-yu State Key Laboratory of Intelligent Construction and Healthy Operation and Maintenance of Deep Underground Engineering Xuzhou 221116China State Key Laboratory for Geomechanics&Deep Underground Engineering China University of Mining and Technology(Beijing)Beijing 100083China Key Laboratory of Shale Gas and Geoengineering Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China CCCC First Highway survey and Design Research institute Co. Ltd.Xi’an 710075China

A comprehensive understanding of the dynamic frictional characteristics in rock joints under high normal load and strong confinement is essential for ensuring the safety of deep engineering construction and mitigating geological *** study conducted shear experiments on rough rock joints under displacement-controlled dynamic normal loads,investigating the shear behaviors of joints across varying initial normal loads,normal loading frequencies,and normal loading *** results showed that the peak/valley shear force values increased with initial normal loads and normal loading frequencies but showed an initial increase followed by a decrease with normal loading *** normal loading can either increase or decrease shear strength,while this study demonstrates that higher frequencies lead to enhanced *** initial normal loading and normal loading frequency result in a gradual decrease in joint roughness coefficient(JRC)values of joint surfaces after *** correlations existed between frictional energy dissipation and peak shear forces,while post-shear joint surface roughness exhibited a negative correlation with peak shear forces through linear regression *** study contributes to a better understanding of the sliding responses and shear mechanical characteristics of rock joints under dynamic disturbances.

关键词： dynamic normal displacement shear strength variations phase lag phenomenon stick-slip

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Contamination assessment,source apportionment and associated health risks of PTEs in agricultural soil under five land-use patterns in Sanya,China

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China geology 2024年第3期7卷 469-479页

作者： Jian-zhou Yang Yan-gang Fu Qiu-li Gong Sheng-ming Ma Jing-jing Gong Jian-weng Gao Zhen-liang Wang Yong-wen Cai Shi-xin Tang institute of Geophysical and Geochemical Exploration Chinese Academy of Geological SciencesChina Geological SurveyLangfang 065000China Key Laboratory of Coupling Process and Effect of Natural Resources Elements Ministry of Natural ResourcesBeijing 100055China

To understand the levels of potentially toxic elements(PTEs)contamination in soils and their effects on human health from different agricultural land use in Sanya,China.12. soil samples(64 topsoil samples and corresponding subsoil samples)were collected from the five representative land-use *** coupled plasma mass spectrometry(ICP-MS),Atomic fluorescence spectrometry(AFS),and Inductively coupled plasma optical emission spectrometry(ICP-OES)were used to determine the content of PTEs(As,Cd,Hg,Cu,Cr,Ni,Pb,Zn,Co,Mo,Sb,and V).Correlation analysis and factor analysis were used to determine the source of ***-accumulation index(I_(geo)),hazard quotient(HQ),and total carcinogenic risk index(TR)were used to measure the PTEs contamination and its relative health *** showed that the average values of 12.PTEs in topsoil were higher than the Hainan soil geochemical baseline,showing different degrees of PTEs accumulation *** concentration of PTEs in the topsoil was lower than those in the subsoil except for Cd and *** I_(geo)revealed that the major accumulated element in soils was As followed by *** apportionment suggested that parent materials and agricultural practices were the dominant factors for PTEs accumulation in the *** risks of soil samples from five land-use patterns presented a trend of paddy field>dry field>woodland>orchard>garden ***,the HQ values of 12.PTEs were less than the recommended limit of HQ=1,representing that there are no non-carcinogenic risks of PTEs for children and adults in the study *** TR values are within 6.95×10^(-6)-1.38×10^(-5),which corresponds to the low *** the PTEs in the agricultural soil of the study area show little influence on the health status of the local population.

关键词： Potentially toxic trace elements(PTEs) Soils Land-use Geo-accumulation index(Igeo) Hazard quotient(HQ) Total carcinogenic risk index(TR) Source apportionment Health risk Agricutural geological survey engineering

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Groundwater recharge via precipitation in the Badain Jaran Desert,China

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Journal of Groundwater Science and Engineering 2024年第1期12卷 109-118页

作者： Zhe Wang Li-juan Wang Jian-mei Shen Zhen-long Nie Le Cao Ling-qun Meng institute of Hydrogeology and Environmental geology Chinese Academy of Geological SciencesShijiazhuang 050061China Technology Innovation Center for Geothermal&Hot Dry Rock Exploration and Development Ministry of Natural ResourcesShijiazhuang 050061China

Precipitation infiltration serves as a significant source of groundwater in the Badain Jaran *** investigate variations in precipitation infiltration within the desert,this study collected data on moisture content and temperature from the vadose zone through in-situ field *** these data,a numerical model is employed to explore the mechanism of groundwater recharge via *** results are as follows:(1)Moisture content and temperature in the shallow vadose zone exhibit significant seasonal variations,with moisture content diminishing with increasing depth;(2.Groundwater recharge via precipitation infiltration initially increases and then decreases with groundwater level depth(GWD).Peak groundwater recharge via precipitation occurs at a GWD of 0.75 m,decreasing to merely 0.012.cm at GWDs exceeding 2.m;(3)Groundwater is no longer susceptible to phreatic water evaporation when the GWD reaches approximately 3.7 ***,GWD plays a crucial role in governing groundwater recharge via precipitation in the Badain Jaran Desert.

关键词： Badain Jaran Desert Vadose zone Groundwater recharge In situ monitoring Numerical simulation

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Sterol Distribution in Sediments from Chaiwobu Lake and Caohai Basin and Its Geochemical Significance

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Chinese Journal Of Geochemistry 1994年第1期13卷 47-54页

作者：史继扬向明菊林树基周启永 1. Guangzhou institute of New Techniques for geology Chinese Academy of Sciences 510640 Wushan Guangzhou 2. regional Geological survey Party Guizhou Bureau of Geology and Mineral Resources China

In order to understand the distribution characteristics of biomarkers in source rocks, which maybe related to organic input, Quaternary sediments from the Caohai Basin and the Chaiwobu Lakewere analyzed for sterols. As a result, various sterols have been found in the sediments. The composi-tion of sterols in the sediments revealed that cholesterols and cholestadieno1s are more abundant thantheir C2. counterparts in the Chaiwobu Lake sediments and that C2. sterols are more abundant inthe peats from the Caohai Basin. lt is also found that stanol/sterol ratios in clays are higher than *** show that organic input to the Chaiwobu Lake is mainly plankton and zooplankton andto the Caohai Basin is mainly terrestrial high plant. The authors have proposed that the relativeabundance of C2. or C2. sterane in source rocks may reflect input characteristics to some extent andthe stanol/sterol ratios may reflect the redox conditions of the deposihonal environments.

关键词：沉积物湖泊盆地地球化学标志甾酮

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geology and mineralization of the Dongping supergiant alkalic-hosted Au-Te deposit(>100 t Au)in Northern Hebei Province,China:A review

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China geology 2024年第3期7卷 533-550页

作者： Shi-min Zhen Da-zhao Wang Zhong-jian Zha Hai-jun Bai Jiang Wang Development and Research Center of China Geological survey Ministry of Natural ResourcesBeijing 100037China Technical Guidance Center for Mineral Resources Exploration Ministry of Natural ResourcesBeijing 100037China State Key Laboratory of Nuclear Resources and Environment East China University of TechnologyNanchang 330013China institute of Geological surveying and Mapping Technology of Anhui Province Hefei 230022China Third Geological Brigade of Hebei Bureau of geology and Mineral Resources Zhangjiakou 075000China Ulanqab Real Estate Registration Center Ulanqab 012099China

The Dongping deposit is the largest alkalic-hosted gold deposit in China containing>100 t of *** paper presents a new understanding for Dongping ore system,based on the previous *** mineralization originally occurred at 400-380 Ma,simultaneous with emplacement of the Shuiquangou alkaline complex,and was overprinted by the hydrothermal activity in the *** compositions of ores indicate metals of the deposit are mainly provided by the Shuiquangou ***-forming fluids are characterized by increasing oxygen fugacity and decreasing sulfur fugacity,while tellurium fugacity increased in the Stage II-2.and decreased in Stage *** systematic changes are closely related to the processes of mineral precipitation and fluid *** precipitation from Stage Ⅰ to Stage Ⅱ was triggered by fluid boiling,which leads to the precipitation of Pb-Bi-Te,due to decrement of sulfur *** of gas phase containing high concentration of H_2.e leads to precipitation of Te-Au-Ag minerals and native *** on these hypotheses,this paper present a polyphase metallogenic model as *** the Devonian,fluids were released from alkaline magmas,which carried ore-forming materials form the surrounding rocks and precipitate the early *** the Jurassic-Cretaceous,fluorine-rich fluids exsolved from highly factionated Shangshuiquan granite,which extracted and concentrated Au from the Shuiquangou complex and the Sanggan Group metamorphic rocks,and finally formed the Dongping gold deposit.

关键词： Mineralization and alteration Alkaline intrusion Au deposit Physicochemical conditions Metallogenic model Oxygen fugacity Sulfur fugacity Mechanisms of mineral precipitation Fluid boiling Fluorine-enriched fluid Dongping gold deposit North China Craton Mineral exploration engineering

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Correlation of the Tournaisian-Visean Boundary Beds

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Acta Geologica Sinica(English Edition) 2011年第2期85卷 354-365页

作者： HOU Hongfei WU Xianghe YIN Bao＇an institute of geology Chinese Academy of Geological Sciences Beijing 100037 China Guizhou institute of geology Guiyang 550004 China regional Geological survey of Guangxi Guilin 541002 China

With the definition and adoption of the Global Stratotype Section and Point （GSSP） for base of the Visean in China, the newly synthesized zonations and correlation of some significant fossil groups： foraminifera, conodont, coral and brachiopoda near the Tournaisian-Visean boundary beds are reviewed, which help in the recognition of the boundary in various sedimentary facies. The occurrence of two physical events, one pre- and one post- the Tournaisian-Visean boundary is emphasized, which allows for recognition of the position close to the Tournaisian-Visean boundary in the field. The regional correlation in southern China and international correlation throughout Eurasia around the Tournaisian-Visean boundary beds with the GSSP is proposed.

关键词： Carboniferous Tournaisian-Visean boundary Global Stratotype Section and Point foraminifera conodont sedimentary facies China

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Strongly peraluminous granites of Mesozoic in Eastern Nanling Range, southern China: Petrogenesis and implications for tectonics

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Science China Earth Sciences 2005年第2期48卷 165-174页

作者： SUN Tao, ZHOU Xinmin, CHEN Peirong, LI Huimin, ZHOU Hongying, WANG Zhicheng & SHEN Weizhou Department of Earth Sciences, Nanjing University, Nanjing 2.0093, China Tianjin institute of geology and Mineral Resources, China Geological {2., Tianjin 300170, China 1. Department of Earth Sciences Nanjing University 210093 Nanjing China 2. Tianjin institute of geology and Mineral Resources China Geological Survey 300170 Tianjin China

The strongly peraluminous granites (SPGs) of Eastern Nanling Range (ENR) are a characteristic of all bearing highly aluminous minerals, such as muscovite±AI-rich biotite± tourmaline±garnet, and lack of cordierite. In respect of petrography, geochemistry, Nd isotope, and single grain zircon U-Pb dating, the representative granite bodies of them are studied. The research shows that these granites were emplaced in two stages, namely 2.8-2.5 Ma BP and J2.3 159-156 Ma BP, belonging to Indosinian and early Yanshanian periods, respectively, and they have low εNd(t) values (-10.6--11.1), high A/CNK, Rb/Sr ratios and tDM values (1887-1817 Ma), and REE's tetrad effect (TE1,3=1.13-1.34). In comparison with related geology, petrology and chronology of granites in adjacent regions, it is suggested that Indosinian SPGs of ENR formed in the circumstance of post-collisional extension 2. Ma after the major collision of Indosinian Movement (2.8-2.3 Ma BP) in Indo-China Peninsula, and early Yanshanian SPGs formed in the background of back-arc extension setting controlled by paleo-Pacific tectonic domain, and J1, the interval of two stages, is the interim from Tethyan to Pacific tectonic domains in South China. These SPGs have similar geological and geochemical characteristics, because they all crystallized from the magma of partial melting of early Proterozoic metasedimentary rocks when the thickened crust (≤50 km) became thinning, decompression, and transmitting of water.

关键词： Nanling Range, strongly peraluminous granite, petrogenesis of granite, South China.

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Ordovician Proto-basin in South China and its Tectonic Implications: Evidence from the Detrital Zircon U-Pb Ages of the Ordovician in Central Hunan, China

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Acta Geologica Sinica(English Edition) 2020年第6期94卷 2115-2133页

作者： ZHANG Jibiao NI Jingbo LIU Yanxue ZHANG Heng BU Ling institute of geology Chinese Academy of Geological SciencesBeijing 100037China Beijing institute of Geological survey Beijing 102206China Hebei regional Geological survey {2. Hebei 050081China

Caledonian orogeny is another important tectonic event in South China Block after the breakup of the Rodinia *** a view to constrain the tectonic evolution and proto-basin in South China,this paper reports the geochemical and zircon U-Pb dating data of the Ordovician strata in central Hunan,South *** features and paleocurrent directions suggest that the lower Ordovician deposited in a passive continental margin basin with a provenance of quartzose components and showing an affinity with the Yangtze Block.U-Pb age data for 2.0 detrital zircons from upper Ordovician identify three major age populations as:900-12.0 Ma,1400-1800 Ma and 2.00-2.00 *** detrital zircon age spectrum as well as the paleocurrent directions suggest that upper Ordovician deposited in a foreland basin and showing a close affinity with the Cathaysia *** is also suggest that the lower Ordovician continuously accepted the mineral from the Yangtze Block,whereas the provenance of the upper Ordovician sedimentary basin changed from the Yangtze Block to the Cathaysia *** change implies a tectonic movement,which caused the transformation of the proto-basin in the Hunan area in SCB from passive continental margin basin to foreland basin probably took place during late *** fact also demonstrate that the Caledonian orogeny in South China Block began no later than 453 Ma,and a new crustal evolution model is proposed.

关键词： U-Pb chronology Ordovician Proto-basin Caledonian orogeny South China

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Magma underplating and Hannuoba present crust-mantle transitional zone composition: Xenolith petrological and geochemical evidence

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Science China Earth Sciences 2005年第8期48卷 1089-1105页

作者： FAN Qicheng1,2. ZHANG Hongfu1, SUI Jianli1, ZHAI Mingguo1, SUN Qian2.& LI Ni2.1. institute of geology and Geophysics, Chinese Academy of Sciences, Beijing 10002., China 2. institute of geology, China Seismological Bureau, Beijing 10002., China 1. institute of geology and Geophysics Chinese Academy of Sciences 100029 Beijing China 2. institute of geology China Seismological Bureau 100029 Beijing China

On the basis of mineral assemblage, mineralogy, petrology, and major, trace ele-mental and isotopic geochemistry of the underplated granulite- and eclogite-facies accumulate, peridotite and pyroxenite xenoliths entrained in Hannuoba Cenozoic basalts, this work con-strained the petrological constituents for the crust-mantle transitional zone, which is supported by the results of high-temperature and pressure velocity experiments on rocks and geophysics deep survey. Present lower part of lower crust is mainly composed of granulite-facies mafic accumu-lates (dominantly plagioclase websterite) and crust-mantle transitional zone dominantly com-posed of eclogite-facies pyroxenites with or without garnet and spinel lherzolites; Archaean ter-rain granulite is only nominally early lower crust. Magma underplating in the crust-mantle boundary led to the crustal vertical accretion and the formation of the crust-mantle transitional zone, which is a significant mechanism for the chemical adjustment of the crust-mantle boundary since the Phanerozoic.

关键词： magma underplating, xenolith petrology, geochemistry, cust-mantle boundary constituent, Hannuoba.

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The suitability assessment on site selection for bottom seeding scallop culture based on analytic hierarchy process

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Journal of Oceanology and Limnology 2024年第2期42卷 647-663页

作者： Ziniu ZHANG Zhenyan WANG Guihua LI Meihan ZHAO Wenjian LI School of Earth Sciences and Engineering Shandong University of Science and TechnologyQingdao 266590China Key Laboratory of Marine geology and Environment Institute of OceanologyChinese Academy of SciencesQingdao 266071China Laboratory for Marine Mineral Resources National Laboratory for Marine Science and TechnologyQingdao 266237China University of Chinese Academy of Sciences Beijing 100049China

Scallop culture is an important way of bottom-seeding marine ranching,which is of great significance to improve the current situation of fishery ***,there are some problems in site-selection evaluation of marine ranching,such as imperfect criteria system,complex structure,untargeted criteria quantification,*** addition,no site-selection evaluation method of bottom-seeding culture areas for scallops is ***,we established a hierarchy structure model according to the analytic hierarchy process(AHP)theory,in which social,physical,chemical,and biological environments are used as main criteria,and marine functional zonation,water depth,current,water temperature,salinity,substrate type,water quality,sediment quality,red tide,phytoplankton,and zooplankton are used as sub-criteria,on which a multi-parameter evaluation system is set ***,the dualism method,assignment method,and membership function method were used to quantify sub-criteria,and a quantitative evaluation for the entire criteria was added,including the evaluation and analysis of two types of unsuitable environmental *** overall consideration in scallop yield,quality,and marine ranching construction objectives,the weight of the main criteria could be *** grades in the suitability corresponding to the evaluation result were divided,and the Python language was used to create an evaluation system for efficient calculation and intuitive presentation of the evaluation *** marine cases were simulated based on existing survey data,and the results prove that the method is feasible for evaluating and analyzing the site selection of bottom-seeding culture areas for scallops under various environmental *** proposed evaluation method can be promoted for the site selection of bottom-seeding marine *** study provided theoretical and methodological references for the site selection evaluation of other types of marine ranching.

关键词： marine ranching bottom-seeding scallops site selection evaluation analytic hierarchy process evaluation system

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