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Acta Geologica Sinica(English Edition) 2020年第4期94卷 877-883页

作者： WAN Yusheng DONG Chunyan xiE Hangqian WANG Shijin Beijing SHRIMP center Institute of GeologyChinese Academy of Geological SciencesBeijing 100037China Shandong geological survey Institute Jinan 250013China

Komatiites are presented as direct evidence for higher mantle temperatures during the Archean. In the North China Craton, komatiites with spinifex structure have been identified only at one locality, i.e. the Sujiagou area, western Shandong. They were considered as formed during the early Neoarchean mainly based on their association with supracrustal rocks considered to be that age. This study carried out SHRIMP U-Pb zircon dating on metamorphosed trondhjemitic and monzogranitic dykes intruding the Sujiagou komatiites, and they have magmatic zircon ages of 2592 ± 12 Ma and 2586 ± 13 Ma respectively. This provides direct evidence that the komatiites formed during the early Neoarchean.

关键词： granitic dyke SHRIMP U-Pb zircon dating Sujiagou komatiite Neoarchean western Shandong

Isotope tracers for deep-seated fluids and noble gases

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Chinese Journal Of Geochemistry 2013年第2期32卷 195-202页

作者： WANG Baode NIU Shuyin SUN Aiqun ZHANG Jianzhen WANG xiang WANG Chuen Institution of geological survey Shijiazhuang University of Economics Qingdao Institute of geological Engineering and Exploration

The role of He and Ar isotopes in tracing the source of ore fluids has aroused great attention of the broad masses of the geological researchers. On the basis of lots of test and measurement of He and Ar isotopes in sulfides from Au, Ag polymetallic ore deposits in northern China, statistics has been made on the published He and Ar isotope data from 27 gold deposits, 13 silver polymetallic ore deposits, 8 polymetallic ore deposits, 1 rare-earth deposit, 3 oceanic incrustations, 3 volcanic springs and their wall rocks and granites. The statistical results indicate that the 3 He/ 4 Ar (×10-6 ) values of the Au, Ag polymetallic ore deposits are within the range of 0.24 9.39, with an average of 3.34×10-6 ; the He/Ar values, 0.007 6.01,with an average of 2.37; the 40 Ar/ 36 Ar values, 265.75 2361, with an average of 699.0; the 4 He/ 40 Ar values, 0.0020 643.86, with an average of 5.85, the 3 He/ 4 Ar (×10-6 ) values of gneiss and granite surrounding the mining area, 0.001 1.79, with an average of 1.00×10-6 , reflecting great differences in source. Mantle-source He in 48 Au, Ag polymetallic ore deposits accounts for 4.55% 83.06%, averaging 29.91%. It falls near the mantle-source region which can be seen in the He isotopic concentration diagram and the 3 He/ 4 He(R/Ra) 40 Ar/ 36 Ar plot. Studies suggested that the ore-forming materials for endogenic Au, Ag polymetallic ore deposits should be derived from the deep interior of the Earth, and with the multi-stage evolution of mantle plumes the deep-seated ore fluids would be transported from the deep interior of the Earth to the shallow levels. During this process the mixing of crust/mantle-source fluids would inevitably occur, therefore, the value range always lies between the mantle and the crust.

关键词：成矿流体同位素示踪稀有气体银多金属矿床氦同位素氩同位素幔源流体地球内部

In Situ Rb-Sr Dates of Muscovite and Sulfur Isotope of Pyrite from the Yangshan Gold Deposit in Western Qinling,China

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Acta Geologica Sinica(English Edition) 2023年第5期97卷 1475-1489页

作者： HUANG Yong QI xianmao WU Qingsong LI Jianzhong REN Minghua DUAN Liu’an xiONG Tao YANG Zhonghu ZHAO Yang CIREN Lamu WEI Wei DUAN Jilin YAN Mengmeng Civil-Military Integration center of China geological survey Chengdu 610036China China University of Geosciences Wuhan 430074China Department of Geoscience University of NevadaLas Vegas 89154-4010USA Yantai geological survey center of Coastal Zone China Geological SurveyYantaiShandong 264000China East China University of Technology Nanchang 330013China

Located along the southern part of the West Qinling orogenic belt,the Yangshan gold deposit is one of the largest in *** major gold ores of Yangshan are disseminated in metasedimentary host rocks with minor native gold amounts in stibnite-gold quartz *** and arsenopyrite are the major Au-bearing *** muscovite from gold-bearing quartz veins was dated using the in situ Rb-Sr method to determine the formation age of the Yangshan gold *** Rb-Sr isochron date of the muscovite yielded 210.1±5.6 Ma(MSWD=1.2).This date is near the lower end of the period of the mineralized granitic dykes(210.49-213.10 Ma).Two stages of gold enriching process are recognized in the gold-bearing pyrite:the first is incorporated with the Co,Cu,As,Ni enrichment;and the second is accompanied by Bi,Co,Ni,Pb,Cu,Sb *** in-situ sulfur isotopic values of pyrites show a restrictedΔ34s range of-1.43‰to 2.86‰with a mean value of 0.43‰.Trace-element mapping and in-situ sulfur isotopic analysis of pyrite suggest that the sulfur deposits are likely derived from a magmatic source and likely assimilated by sulfur from the sedimentary ***,magmatism plays a critical role in the formation of the Yangshan gold deposit.

关键词： Rb-Sr dating trace-element mapping sulfur isotope gold deposit Yangshan Qinling orogenic belt

Regulation of vegetation pattern on the hydrodynamic processes of erosion on hillslope in Loess Plateau,China

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Journal of Groundwater Science and Engineering 2023年第1期11卷 4-19页

作者： Guo-Qiang Yu Qian Wang Li-Feng Zhu xia Zhang Key Laboratory of Groundwater and Ecology in Arid and Semi-arid Areas Xi’an Center of Geological SurveyChina Geological SurveyXi’an 710054China Shaanxi Province Engineering Research Centre of Water Resources and Environment Xi’an 710054China State Key Laboratory of Eco-hydraulics in Northwest Arid Region Xi’an University of TechnologyXi’an 710048China

As vegetation are closely related to soil erosion,hydrodynamic parameter changes under various vegetation pattern conditions can be used as an important basis for the research of the soil erosion *** upstream water inflow experiments conducted on a loess hillslope,how the vegetation pattern influences the hydrodynamic processes of sediment transport was *** results show that the placement of a grass strip on the lower upslope can effectively reduce runoff erosion by 69%,relying on the efficiency of regulated hydrodynamic *** effective location of grass strip for hillslope alleviating erosion is on the lower part of the upslope,mainly due to the grass strip measure used to regulate the hydrodynamic *** a result,the underlying surface runoff resistance is increased by 5 times,runoff shear stress is decreased by more than 90%,and runoff power decreased by over 92%.The measure greatly separates the scouring energy of surface runoff that acts on the slope ***,the use of grass strips effectively decreases the energy of runoff flowing along the slope,eliminating soil erosion to a great extent and thereby achieving a better regulation of hydrodynamic processe.

关键词： Soil erosion Grass strip Scouring experiment Sediment transport Regulating mechanism Loess Plateau

Identification of the Concealed Structures in the Beiya Area of Western Yunnan

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Acta Geologica Sinica(English Edition) 2015年第5期89卷 1779-1780页

作者： WANG Qiao YANG Jian YAO Wen YANG Junbo Chengdu center of China geological survey The School of Geophysics Chengdu University of Technology

The interpretation of regional gravity and magnetic data, especially the extracted information about concealed targets and structures, provide important evidence for geological structure research, oil-gas resource assessment, mineral potential forecast and prospective area delineation. Several interpretation methods have been proposed to determine structural boundary, including vertical derivative, horizontal first-order derivative, total horizontal derivative, total gradient modulus, tilt derivative, and theta graph, and each have their advantages and disadvantages. This study used the tilt derivate method to obtain bouguer gravity anomalies in the Beya area, as shown in Fig. 1a.

关键词： Identification of the Concealed Structures in the Beiya Area of Western Yunnan AMT

Theoretical System of Sandstone-Type Uranium Deposits in Northern China

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Journal of Earth Science 2022年第2期33卷 257-277页

作者： Ruoshi Jin Huajian Liu xiaoguang Li Tianjin Centre China Geological SurveyTianjin 300170China Key Laboratory of Uranium Geology China Geological SurveyTianjin 300170China

Many theoretical results on sandstone-type uranium mineralization in northern China obtained by the uranium research team of the Tianjin center of geological survey in recent years are *** the source sink system of uranium-producing basins,sedimentary environment of uranium-bearing rock series,ore-forming fluid information,evolution of tectonic events,basin formation and development,we redefine and classify uranium orebodies,redox zoning,and ore-controlling structural *** then systematically propose a theoretical system of sandstone-type uranium deposits in northern *** conclude that sandstone-type uranium deposits in northern China are mainly found in sedimentary environments such as rivers,deltas,and alluvial fans in the Mesozoic and Cenozoic lowstand systems tract and in gray sandstone layers in the vertical redox *** orebodies are controlled by the tectonic slope belt,which is in the shape of a strip on the plane,and spreads in a layer or plate on the ***(ups and downs)tectonic movement triggers large-scale phreatic flow in the basin,which is the real driving force for controlling the ore-forming *** theoretical system of sandstone-type uranium deposits in northern China should be based on global tectonic movement and environmental changes and take into account factors such as basins as a unit to study mineralization background,ore concentration areas as objects to study mineralization,and the correlation between regional tectonic movement and metallogenic process as a breakthrough point to study tectonic events and metallogenic *** should also be based on different basin types to establish metallogenic *** innovative research results and ideas are summarized with the aim of promoting the continuous improvement of sandstone-type uranium mineralization theory in northern China.

关键词： theoretical system metallogenic background mineralization metallogenic model vertical(ups and downs)tectonic movement sandstone-type uranium deposits ore deposit geology

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Science China(Information Sciences) 2016年第11期59卷 220-223页

作者： Zhangbing ZHOU Zehui CHENG Yueqin ZHU School of Information Engineering China University of Geosciences (Beijing) Development Research center of China geological survey and Key Laboratory of Geological Information TechnologyMinistry of Land and Resources

This article proposes to identify and recommend scientific workflows for reuse and ***, a scientific workflow is represented as a layer hierarchy that specifies the hierarchical relations between this workflow, its sub-workflows, and activities. Semantic similarity is calculated between layer hierarchies of workflows. A graph-skeleton based clustering technique is adopted for grouping layer hierarchies into *** in each cluster are identified, which serve as core workflows in this cluster, for facilitating the cluster identification and workflow ranking and recommendation with respect to the requirement of scientists.

关键词： scientific workflow reuse and repurposing layer hierarchy graph-skeleton recommendation

Taipingite-(Ce),(Ce73+,Ca2)∑9Mg(SiO4)3[SiO3(OH)]4F3,a new mineral from the Taipingzhen REE deposit,North Qinling Orogen,central China

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Geoscience Frontiers 2020年第6期11卷 2339-2346页

作者： Kai Qu xianzhang Sima Guang Fan Guowu Li Ganfu Shen Huakai Chen xing Liu Qingqing Yin Ting Li Yanjuan Wang Tianjin center China Geological SurveyTianjin 300170China Beijing Research Institute of Uranium Geology Beijing 100029China China University of Geosciences(Beijing) Beijing 100083China Chengdu center China Geological SurveyChengdu 610081China Henan Nuclear geological Bureau Zhengzhou 450044China

A new cerite group mineral species,taipingite-(Ce),ideally(Ce7^3+,Ca2)∑9Mg(SiO4)3[SiO3(OH)]4 F3,has been found in the Taipingzhen rare earth element(REE)deposit in the North Qinling Orogen(NQO),Central *** forms subhedral grains(up to approximately 100 μm×200 μm)commonly intergrown with the REE mineral assemblages and is closely associated with allanite-(Ce),gatelite-(Ce),tornebohmite-(Ce),fluocerite-(Ce),fluocerite-(La),fluorite,bastnasite-(Ce),parisite-(Ce)and ***-(Ce)is light red to pinkish brown under a binocular microscope and pale brown to colorless in thin section,and it is translucent to transparent with a grayish-white streak and vitreous *** mineral is brittle with conchoidal fracture;has a Mohs hardness value of approximately 51/2 and exhibits no cleavage twinning or *** calculated density is 4.900(5)g/***,taipingite-(Ce)is uniaxial(+),withω=1.808(5),ε=1.812(7),c=ε,and a=b=ω.Furthermore,this mineral is insoluble in HCl,HNO3 and H2 *** microprobe analysis demonstrated that the sample was relatively pure,yielding the empirical formula(with calculated H2 O):(Ce4.02La1.64Nd1.49Pr0.41Sm0.10Gd0.02Ho0.02Tm0.01Lu0.02Y0.03Ca0.66Mg0.05Th(0.01-0.51∑9(Mg0.75Fe0.253+)∑1(SiO4)3{[SiO3(OH)]3.98[PO3(OH)]0.02}∑4(F1.81OH1.17Cl0.02∑***-(Ce)is trigonal and exhibits space group symmetry R3 c with unit cell parameters a=10.7246(3)Å,c=37.9528(14)Å,V=3780.39(20)Å3 and Z=*** strongest eight lines in the X-ray diffraction pattern are[d in A(I)(hkl)]:4.518(50)(202),3.455(95)(122),3.297(85)(214),3.098(35)(300),2.941(100)(02,10),2.683(65)(220),1.945(40)(238)and 1.754(40)(30,18).The crystal structure has been refined to a R1 factor of 0.025,calculated for the 2312 unique observed reflections(Fo≥4σ).The mineral is named after its discovery locality and is characterized as the F-dominant analogue of cerite-(Ce).

关键词： Taipingite-(Ce) Cerite group New mineral species Chemical composition Crystal structure North Qinling Orogen

Assessment of geological Security and Integrated Assessment Geo-environmental Suitability in Worst-hit Areas in Wenchuan Quake

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Acta Geologica Sinica(English Edition) 2009年第4期83卷 816-825页

作者： LI Wenpeng WEN Dongguang ZHOU Aiguo SUN xiaoming MENG Hui SHI Jusong CHEN Zongyu ZHANG Liqin FENG xiaoming LIU Changli ZHOU Jianwei China Institute of Geo-Environmental Monitoring Beijing 100081 China geological survey Beijing 100037 Institute of Geomechanics China Academy of Geological Science Beijing 100081 Tianjin geological survey center of CGS Tianjin 300170 Geomechanics Institute of Chinese geological Academy Beijing 100086 Nanjing geological survey center of CGS Nanjing 210016 The Institute of Hydrogeology and Environmental Geology CAGS Shi Jiazhuang 050061

The Wenchuan earthquake in 2008 and geo-hazards triggered by the earthquake caused large injuries and deaths as well as destructive damage for infrastructures like construction, traffic and electricity. It is urgent to select relatively secure areas for townships and cities constructed in high mountainous regions with high magnitude earthquakes. This paper presents the basic thoughts, evaluation indices and evaluation methods of geological security evaluation, water and land resources security demonstration and integrated assessments of geo-environmental suitability for reconstruction in alp and ravine with high magnitude earthquakes, which are applied in the worst-hit areas （12 counties）. The integrated assessment shows that：（1） located in the Longmenshan fault zone, the evaluated area is of poor regional crust stability, in which the unstable and second unstable areas account for 79% of the total; （2） the geo-hazards susceptibility is high in the evaluation area. The spots of geo-hazards triggered by earthquake are mainly distributed along the active fault zone with higher distribution in the moderate and high mountains area, in which the areas of high and moderate susceptibility zoning accounts for 40.1% of the total; （3） geological security is poor in the evaluated area, in which the area of the unsuitable construction occupies 73.1%, whereas in the suitable construction area, the areas of geological security, second security and insecurity zoning account for 8.3 %, 9.3% and 9.3 % of the evaluated area respectively; （4） geo-environmentai suitability is poor in the evaluated area, in which the areas of suitability and basic suitability zoning account for 3.5% and 7.3% of the whole evaluation area.

关键词： Wenchuan earthquake geological security carrying capacity of water and land resources geo-environmental suitability

Age of Yingfeng rapakivi granite pluton on the north flank of Qaidam and its geological significance

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Science China Earth Sciences 2004年第4期47卷 357-365页

作者： xiAO Qinghui1,2, LU xinxiang1,3, WANG Fei4, SUN Yangui5, WEI xiangdong3 & xiNG Zuoyun6 1. Division of Granite Geology, China geological survey, Yichang 443003, China 2. Information center of Ministry of Land and Resources, Beijing 100812, China 3. geological survey of Henan Province and Institute of geological Research of Henan Province, Zhengzhou 450053, China 4. geological Institute, China Seismological Bureau, Beijing 100029, China 5. geological survey Institute of Qinghai Province, xining 810032, China 6. China University of Geosciences, Wuhan 430074, China Division of Granite Geology China Geological Survey Yichang 443003 China Information center of Ministry of Land and Resources Beijing 100812 China geological survey of Henan Province and Institute of geological Research of Henan Province Zhengzhou 450053 China geological Institute China Seismological Bureau Beijing 100029 China geological survey Institute of Qinghai Province Xining 810032 China China University of Geosciences Wuhan 430074 China

The Yingfeng rapakivi granite on the north flank of Qaidam is a newly discovered Proterozoic rapakivi pluton in China, which was found after the discovery of Shachang rapakivi in Miyun County, Beijing and Kuandian rapakivi in Jilin Province. Yingfeng rapakivi pluton is ex-posed on the north side of the suture belt between Qinling-Kunlun orogenic belt and North China plate. U-Pb zircon isotopic dating and Ar-Ar isotopic dating of both hornblende and K-feldspar from the Yingfeng rapakivi granite have been conducted. The results show that the age of (1776±33)Ma at the upper intercept in Concorde diagram represents the age of formation of the plu-ton, whereas the age of (526 281) Ma at the lower intercept and Ar-Ar mineral dating of horn-blende and K-feldspar correspond to the age of a later event affecting the pluton, suggesting that Yingfeng pluton has ever been affected by strong regional Caledonian-Hercynian tectonic movement after its formation. The discovery of middle Proterozoic Yingfeng rapakivi granite pro-vides a petrologic evidence for the timing of cratonization of both the continental crust basement in western China and the basement of the North China plate and for a rifting event taking place in the mid-Proterozoic, suggesting that an amalgamation of ancient China continents had ever happened during the L liang Movement?between the early Proterozoic and the mid-Proterozoic.

关键词： rapakivi, U-Pb dating, Ar-Ar dating, Kunlun-Qinling orogenic belt.