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Mineralization Styles and Genesis of the Yinkeng Au-Ag-Pb-Zn-Cu-Mn Polymetallic Orefield, Southern Jiangxi Province, SE China: Evidence from Geology, Fluid Inclusions, Isotopes and Chronology

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Acta Geologica Sinica(English Edition) 2014年第3期88卷 825-844页

作者： FENG Chengyou LI Daxin ZENG Zailin ZHANG Dequan she hongquan Key Laboratory of Metallogeny and Mineral Resource Assessment Ministry of Land and Resources Institute of Mineral Resources CAGS South Jiangxi Geological Survey Party of JBGMR

The Yinkeng orefield in Yudu County,Jiangxi Province,SE China,is a zone of concentrated Au-Ag-Pb-Zn-Cu-Mn polymetallic *** on summing up basic geology and ore geology of the orefieid,the polymetallic deposits in the orefield have been divided into seven major substyles according to their occurring positions and control *** ore-forming fluid inclusion styles in the orefield include those of two-phase fluid,liquid CO2-bearing three-phase and daughter mineral-bearing *** homogenization temperatures range from 382° to 122℃,falling into five clusters of 370° to 390°,300° to 360°,230° to 300°,210° to 290° and 120° to 200°,and the clusters of 300° to 360°,230° to 300° and 120° to 200° are three major mineralization stages,with fluid salinity peaks from 4.14% to 7.31%,2.07% to 7.31% and 0.53% to 3.90%,*** ore-forming fluids are mainly type of NaCl-H2O with medium to high density （0.74-1.02 g/cm3）,or CO2-bearing NaCl-H2O with medium to low density （0.18-0.79 g/cm3）.The fluid salinity and density both show a decline tendency with decreasing *** to the measurement and calculation of Hand O-isotopic compositions in the quartz of the quartz-sulfide veins,δDV-SMOW of the ore-forming fluid is from-84‰ to-54‰,and δ18OV-SMOW of that is from 6.75‰ to 9.21‰,indicating a magmatic *** δ34SV-CDT of sulfides in the ores fall into two groups,one is from-4.4‰ to 2.2‰ with average of-1.42‰,and the other from 18.8‰ to 21.6‰ with average of 19.8‰.The S-isotopic data shows one peak at-4.4‰ to 2.2‰ （meaning-1.42‰） suggesting a simple magmatic sulfur *** ore Pbisotopic ratios are 206pb/204pb from 17.817 to 17.983,207pb/204pb from 15.470 to 15.620 and 208pb/204pb from 38.072 to 38.481,indicating characteristics of mantle-derived *** data show that the major ore deposits in the orefield have a magmatic-hydrothermal genesis and that the SHRIMP zircon age of the granodiorite porphyry,closely related to the mineralization,is 1

关键词： Ore geology geochemistry fluid inclusion SHRIMP zircon U-Pb dating ore genesis,Carboniferous Jiangxi Province

China's First Independent Cobalt Deposit and its Metallogenic Mechanism:Evidence from Fluid Inclusions and Isotopic Geochemistry

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Acta Geologica Sinica(English Edition) 2011年第6期85卷 1403-1418页

作者： FENG Chengyou QI Feng ZHANG Dequan LI Daxin she hongquan School of Earth and Space Sciences Peking University Beijing 1008 71 China Key Laboratory of Metallogeny and Mineral Resource Assessment Ministry of Land and Resources＂ Institute of Mineral Resources CA GS Beijing 100037 China

The Tuolugou cobalt deposit is the first independent large-scale Co- and Au-bearing deposit discovered in northwestern China. It is located in the eastern Kunlun orogenic belt in Qinghai Province, and occurs conformably in low-grade metamorphic volcano-sedimentary rock series with well-developed Na-rich hydrothermal sedimentary rocks and typical hydrothermal sedimentary ore fabrics. Fluid inclusions and isotopic geochemistry studies suggest that cobalt mineralizing fluid is dominated by NaCI-H20 system, accompanied by NaCI-CO2-H20-N2 system responsible for gold mineralization. Massive, banded and disseminated pyrite ores have similar compositions of He and Ar isotopes from the mineralizing fluid, with 3He/4He range between 0.10 to 0.31Ra （averaging 0.21Ra）, and 4~Ar/36Ar between 302 and 569 （averaging 373）, which reflects that Co mineralizing fluids derived dominantly from meteoric water deeply circulating. ~34S values of pyrite approaches to zero （~34S ranging from -4.5%o to ＋1.5%o, centering around -1.8%o to -0.2%o）, reflecting its deep source. Ore lead is characterized by distinctly high radiogenesis, with 2~6pb/2~4pb〉19.279, 2~7pb/2~4pb〉15.691 and 2~spb/2~4pb〉39.627, and its values show an increase trend from country rocks, regional Paleozoic volcanic rocks to ores. This may have suggested that high radiogentic ore Pb derived mainly from country rocks by leaching meteoric water-dominated hydrothermal fluid during its circulation at depth. Cobalt occurs mainly in sulfide phase （such as pyrite）, but cobalt enrichment, and presence and increasing contents of Co-bearing minerals have a positive correlation with metamorphic degree. The Tuolugou deposit and other typical strata-bound Co-Cu-Au deposits have striking similarities in the geological features and metallogenic pattern of primary cobalt. All of them are syngenetic hydrothermal exhalative sedimentation in origin.

关键词： cobalt deposit fluid inclusion isotopic geochemistry SEDEX metallogenic mechanism Tuolugou in Qinghai Province eastern Knnlun orogenic belt

Late Jurassic Volcanism Deduced from Geochemical,Geochronological,and Sr-Nd-Hf Isotopic Composition Characteristics of the Nanyuan Formation,South China

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Acta Geologica Sinica(English Edition) 2023年第2期97卷 449-468页

作者： WANG Dongsheng LI Jinwen she hongquan WANG Kunming YANG Junzhi REN Chenghao MNR Key Laboratory of Metallogeny and Mineral Assessment Institute of Mineral ResourcesChinese Academy of Geological Sciences(CAGS)Beijing 100037China Forestry and Grassland Administration of Shanxi Province Taiyuan 030021China

The Nanyuan Formation contains information related to the Mesozoic tectonic *** this study,three representative profiles were surveyed from the Nanyuan Formation,and multiple analyses were *** U-Pb dating yielded their ages as approximately 158–146 *** volcanic rocks are enriched in Rb,Th,U,K,and Pb and depleted in Nb,Ta,P,and Ti,implying their affinity for I-type ***εNd(t)values(-8.3 to-6.0),^(87)Sr/^(86)Sr)i values(0.7077–0.7094)of the volcanic rock,andεHf(t)values(-8.71 to 0.12)of the Mesozoic zircons suggest that the Nanyuan Formation magma originated in the lower crust with the involvement of depleted mantle *** parent rocks of the rhyolitic and dacitic volcanic rocks formed by partial melting of basement rocks in South China and the andesitic volcanic rocks were derived from partial melting of the metasomatites generated by slab-mantle *** fractional crystallization also played an important role in later *** diagrams of the volcanic rocks indicated that they formed in a volcanic arc *** with previous data,the Nanyuan Formation recorded subduction of the Paleo-Pacific Plate before regional tectonic *** compressive stress field endured until the end of the Late Jurassic.

关键词： Late Jurassic Nanyuan Formation volcanic rocks volcanic arc geochemistry petrogenesis Pinghe

Isotopes and Geochronology of the Meixian-type Pb-Zn-(Ag)Deposits,Central Fujian Rift,South China:Implications for Geological Events

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Acta Geologica Sinica(English Edition) 2008年第4期82卷 826-837页

作者： FENG Chengyou ZHANG Dequan LI Daxin she hongquan DONG Yingjun Institute of Mineral Resources Chinese Academy of Geological Sciences Beijing 100037

Central Fujian Rift is another new and important volcanogenic massive sulfide Pb-Zn polymetallic metallogenetic belt. In order to find out the material genesis and mineralization period of Meixian-type Pb-Zn-Ag deposits, S and Pb isotope analysis and isotope geochronology of ores and wall rocks for five major deposits are discussed. It is concluded that the composition of sulfur isotope from sulfide ore vary slightly in different deposits and the mean value is close to zero with the 834S ranging from -3.5‰ to ＋5.6‰ averaging at ＋2.0‰, which indicates that the sulfur might originate from magma or possibly erupted directly from volcano or was leached from ore-hosted volcanic rock. The lead from ores in most deposits displays radioactive genesis character （206pb/204pb〉18.140, 207Pb/204pb〉15.584, 208pb/204pb〉38.569） and lead isotope values of ores are higher than those of wall rocks, which indicates that the lead was likely leached from the ore-hosted volcanic rocks. Based on isotope data, two significant Pb-Zn metallogenesis are delineated, which are Mid- and Late-Proterozoic sedimentary exhalative metailogenesis （The single zircon U-Pb, Sm-Nd isochronal and Ar-Ar dating ages of ore- hosted wall rocks are calculated to be among 933-1788 Ma.） and Yanshanian magmatic hydrothermal superimposed and alternated metallogenesis （intrusive SHRIMP zircon U-Pb and Rb-Sr isochronal ages between 127-154 Ma）.

关键词： Meixian-type deposit sulfur and lead isotopes mineralogetic epoch metallizing genesis,Central Fujian Rift

Distribution of δ^(34)S and δ^(18)O in SO_4^(2-) in Groundwater from the Ordos Cretaceous Groundwater Basin and Geological Implications

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Acta Geologica Sinica(English Edition) 2010年第2期84卷 432-440页

作者： YANG Yuncheng sheN Zhaoli WEN Dongguang HOU Guangcai she hongquan ZHAO Zhenhong WANG Dong LI Jingwen Institute of Mineral Resources Chinese Academy of Sciences Beijing 100037 China Xi＇an institute of Geology and Mineral Resources Xi＇an 710054 China China University ofGeosciences Beijing 100083 China China Geological Survey Beijing 100011 China

The Ordos Cretaceous Groundwater Basin, located in an arid-semiarid area in northwestern China, is a large-style groundwater basin. SO4^2- is one of the major harmful components in groundwater. Dissolved SO4^2- concentrations, and δ^34S-SO4^2- and δ^18O-SO4^2- in groundwater from 14 boreholes and in gypsum from aquifer were analyzed. Results show that SO4^2- in shallow groundwaters originates from precipitation, sulfide oxidation, and dissolution of stratum sulphate, with a big range of δ^34S values, from -10.7‰ to 9.2‰, and addition of SO4^2- in deep groundwater results from dissolution of stratum sulphate, with bigger δ^34S values, from 7.8‰ to 18.5‰, compared with those in shallow groundwater. This research also indicates that three types of sulphate are present in the strata, and characterized by high δ^34S values and high δ^18O values-style, high δ^34S values and middle δ^18O valuesstyle, middle δ^34S values and low δ^18O values-style, respectively. The δ^34S-SO4^2- and δ^18O-SO4^2- in groundwater have a good perspective for application in distinguishing different groundwater systems and determining groundwater circulation and evolution in this area.

关键词： sulphate sulfide sulfur isotope oxygen isotope Ordos Groundwater Basin

GEODYNAMICS ON THE FORMATION OF BASIN- AND-RANGE SYSTEM AND ITS RELATIONSHIP TO GAS AND OIL ACCUMULATION

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Scientia Geologica Sinica 1999年第3期 359-366页

作者： she hongquan and Xu Guizhong(Institute of Geology, Chinese Academy of Sciences, Beijing 100029)Yan Danping(China University of Geoscience, Beijing 100083)

The coupling of basin and orogen is a common phenomenon in continellt tectonics. In the paper, we callthe basin and orogen that have close relationship in origin and resulted from the united geologicalbackground as basin-andirange system. Based on its geodynndc featues, basin-and-range systeth isclassified into compession, extensional and sliding tyPes. Its relationship with the oil-gas enrichment,especially in foreland basin-orogen system, is discussed.

关键词： GAS AND-RANGE SYSTEM AND ITS RELATIONSHIP TO GAS AND OIL ACCUMULATION GEODYNAMICS ON THE FORMATION OF BASIN ITS

Vision-Based Adaptive Prescribed-Time Control of UAV for Uncooperative Target Tracking with Performance Constraint

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Journal of Systems Science & Complexity 2024年第5期37卷 1956-1977页

作者： she Xuehua MA Hui REN Hongru LI Hongyi School of Automation and the Guangdong Provincial Key Laboratory of Intelligent Decision and Cooperative Control Guangdong University of Technology School of Mathematics and Statistics Guangdong University of Technology College of Electronic and Information Engineering and Chongqing Key Laboratory of Generic Technology and System of Service Robots Southwest University

This paper discusses the uncooperative target tracking control problem for the unmanned aerial vehicle(UAV) under the performance constraint and scaled relative velocity constraint, in which the states of the uncooperative target can only be estimated through a vision sensor. Considering the limited detection range, a prescribed performance function is designed to ensure the transient and steady-state performances of the tracking system. Meanwhile, the scaled relative velocity constraint in the dynamic phase is taken into account, and a time-varying nonlinear transformation is used to solve the constraint problem, which not only overcomes the feasibility condition but also fails to violate the constraint boundaries. Finally, the practically prescribed-time stability technique is incorporated into the controller design procedure to guarantee that all signals within the closed-loop system are *** is proved that the UAV can follow the uncooperative target at the desired relative position within a prescribed time, thereby improving the applicability of the vision-based tracking approach. Simulation results have been presented to prove the validity of the proposed control strategy.

关键词： Nonlinear transformation performance constraint prescribed-time tracking uncooperative target vision-based measurement

Promotion effects of salt-alkali on ammonia volatilization in a coastal soil

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Pedosphere 2024年第1期34卷 191-199页

作者： Zhenqi SHI Dongli she Yongchun PAN Yongqiu XIA College of Agricultural Science and Engineering Hohai UniversityNanjing 210098China Jiangsu Province Engineering Research Center for Agricultural Soil-Water Efficient Utilization Carbon Sequestration and Emission ReductionNanjing 210098China Key Laboratory of Soil and Sustainable Agriculture Institute of Soil ScienceChinese Academy of SciencesNanjing 210008China

Coastal ecosystems are highly susceptible to salt-related problems due to their formation process and geographical location. As such ecosystems are the most accessible land resources on Earth, clarifying and quantifying the effects of salt-alkali conditions on N concentration and ammonia(NH_(3)) volatilization are pivotal for promoting coastal agricultural productivity. The challenge in establishing this effect is to determine how salt-alkali conditions impact NH_(3) volatilization through direct or indirect interactions. An incubation experiment using a coastal soil from a paddy farmland, combined with the structural equation modeling(SEM) method, was conducted to reveal the net effects of salt-alkali on NH_(3) volatilization and the role of environmental and microbial factors in mutual interaction networks. The specific experimental design consisted of four salt treatments(S1, S2, S3, and S4: 1‰, 3‰, 8‰, and 15‰ NaCl by mass of soil, respectively), four alkaline treatments(A1, A2, A3, and A4: 0.5‰, 1‰, 3‰, and 8‰ NaHCO_(3)by mass of soil, respectively) and a control without NaCl or NaHCO_(3) addition(CK), and each treatment had three urea concentrations(N1, N2, and N3: 0.05, 0.10, and 0.15 g N kg^(-1) soil,respectively) and three replicates. At the N1, N2, and N3 levels, NH_(3)volatilization increased by 9.31%–34.98%, 3.07%–26.92%, and 2.99%–43.61% as the NaCl concentration increased from 1‰ to 15‰, respectively, compared with CK. With an increase in the NaHCO_(3)concentration from 0.5‰ to 8‰, NH_(3) volatilization increased by 8.36%–56.46%, 5.49%–30.10%, and 30.72%–73.18% at the N1, N2, and N3 levels, respectively, compared with CK. According to the SEM method, salinity and alkalinity had positive direct effects on NH_(3)volatilization, with standardized path coefficients of 0.40 and 0.19, *** the total effects(net positive and negative effects) in the SEM results, alkalinity had a greater influence than salinity(total standardized coefficien

关键词： alkalinity coastal ecosystem NH_(3)emission N-transforming microbe salinity structural equation modeling

Chord length sampling correction analysis for dispersion fuel in Monte Carlo simulation

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Nuclear Science and Techniques 2024年第4期35卷 57-64页

作者： Zhao-Yu Liang Ding she Yu-Tong Wen Lei Shi Institute of Nuclear and New Energy Technology(INET) Key Laboratory of Advanced Reactor Engineering and Safety of Ministry of EducationTsinghua UniversityBeijing 100084China

Dispersion fuels,knowned for their excellent safety performance,are widely used in advanced reactors,such as hightemperature gas-cooled *** with deterministic methods,the Monte Carlo method has more advantages in the geometric modeling of stochastic *** explicit modeling method has high computational accuracy and high computational *** chord length sampling(CLS)method can improve computational efficiency by sampling the chord length during neutron transport using the matrix chord length?s probability density *** study shows that the excluded-volume effect in realistic stochastic media can introduce certain deviations into the CLS.A chord length correction approach is proposed to obtain the chord length correction factor by developing the Particle code based on equivalent transmission *** numerical analysis against reference solutions from explicit modeling in the RMC code,it was demonstrated that CLS with the proposed correction method provides good accuracy for addressing the excludedvolume effect in realistic infinite stochastic media.

关键词： Stochastic media Monte Carlo Chord length sampling Excluded-volume effect Chord length correction