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Petrology,Zircon Chronology and Geochemistry of the Late silurian Ophiolitic Mélanges and the Baiyu.s.an Forearc Complex in the Central Beishan Orogenic Belt,NE China

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Journal of Earth science 2023年第2期34卷 444-455页

作者： Hou-Tian Xin Jian Tian Xue-Jian Teng Li-Xin sun Guo-Zhen Zhang Yong Zhang Bang-Fang Ren shenyang Center China Geological SurveyShenyang 110086China Tianjin Center China Geological SurveyTianjin 300170China

The WNW-EsE-trending Baiyu.s.an ophiolitic mélange is exposed in the central Beishan orogenic belt(BOB),between the Hongliuhe-Niujuanzi and Xichangjing ophiolitic mélanges in the west and east,*** we present new petrological,geochemical,and zircon u-Pb age data for the Baiyu.s.an ophiolitic mélange and metamorphosed lithic sandstones of“the Baiyu.s.an Formation”.The Baiyu.s.an ophiolitic mélange is characterized by a block-in-matrix structure,and the blocks of ultramafic-mafic rocks are mainly pyroxenites,dunites,gabbros,and minor *** u-Pb dating yielded an emplacement age of 424.2±3.7 Ma for the *** ultramaficmafic rocks have geochemical features of supra-subduction zone-type ophiolites,including low Ti contents(TiO2=0.01 wt.%–0.35 wt.%),negative Nb-Ta anomalies,and u.s.aped rare earth element patterns with positive Eu anomalies(δEu=0.99–3.25).“The Baiyu.s.an Formation”is exposed to the north of the ophiolitic mélange,and comprises mainly meta-cherts in its lower part and metasandstones and marbles in its upper *** of basalt are locally dispersed in the sand-slate *** ages of detrital zircons in the metamorphosed lithic sandstones range from 521 to 464 Ma,with an age peak of 500 Ma,which is similar to those of the Gongpoquan arc in the *** central Beishan orogenic belt experienced continuous subduction of the Hongliuhe-Xichangjing oceanic lithosphere in the Late silurian,which produced the Baiyu.s.an forearc complex and supra-subduction zone-type ophiolite.

关键词： Beishan orogenic belt the Hongliuhe-Xichangjing Ocean the ultramafic-mafic rocks Late silurian ssZ-type ophiolite subduction and accretion geochemistry

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EFFECTs OF WATER MANAGEMENT ON sEDIMENT TRANsPORT IN CHINA's YELLOW RIVER, WITH COMPARIsONs FROM THE uNITED sTATEs

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International Journal of sediment Research 2003年第2期 285-290页

作者： John R. GRAY,W. R. OsTERKAMP,Jianhua Xu Hydrologist u.s. geological survey Research Hydrologist u.s. geological survey Chief Engineer Water Resources Research Institute Bureau of Hydrology Yellow River Conservancy Commission Reston Virginia Tu.s.n Arizona Zhengzhou China

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The Iu.s.IAGC Task Group on Global Geochemical Baselines

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地学前缘 2012年第3期19卷 1-6页

作者： David B.smith shaun Reeder Alecos Demetriades u.s.geological survey DenverCO 80225 USA Institute of Geopkysical and Geochemical Exploration Langfang Hebei 065000 China British geological survey KeyworthNottinghamUK Institute of Geology and Mineral Exploration Athens Greece

The Task Group on Global Geochemical Baselines,operating under the auspices of both the International union of geological sciences(Iu.s. and the International Association of Geochemistry(IAGC),has the long-term goal of establishing a global geochemical database to document the concentration and distribution of chemical elements in the Earth's surface or near-surface *** database and accompanying element distribution maps represent a geochemical baseline against which future human-induced or natural changes to the chemistry of the land surface may be recognized and *** order to accomplish this long-term goal,the activities of the Task Group include:(1) developing partnerships with countries conducting broad-scale geochemical mapping studies;(2) providing consultation and training in the form of workshops and short cou.s.s;(3) organizing periodic international symposia to foster communication among the geochemical mapping community;(4) developing criteria for certifying those projects whose data are acceptable in a global geochemical database;(5) acting as a repository for data collected by those projects meeting the criteria for standardization;(6) preparing complete metadata for the certified projects;and(7) preparing,ultimately,a global geochemical *** paper summarizes the history and accomplishments of the Task Group since its first predecessor project was established in 1988.

关键词：国际地质科学联合会伴生元素化学元素地表环境

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Geochronology and Petrogenesis of Granitoid Intrusions in the Feidong District, southern Tan-Lu Fault Zone, China

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Acta Geologica sinica(English Edition) 2020年第6期94卷 1960-1976页

作者： Fu Xiang ZHANG Dayu YAO Ziwei REN Kangda DENG Yufeng LI Jiahao JIANG Ren YuAN Feng school of Resources and Environmental Engineering Hefei University of TechnologyHefei 230009China Nanjing geological survey Center China Geological SurveyNanjing 210016China

The Feidong district is located in the southern segment of the Tan-Lu fault zone that separates the south China Block(NCB)from the North China Craton(NCC).We report zircon u-Pb geochronology and Hf isotope data,as well as whole-rock geochemistry for Xishanyi granodiorite and Jianshan granite in the Feidong *** u-Pb dating results show that the emplacement ages of the Xishanyi and Jianshan intrusions are 124±3 Ma and 130±1 Ma respectively,coeval with magmatic events linked to large-scale lithospheric thinning in eastern *** whole-rock geochemistry of the Xishanyi and Jianshan intrusions demonstrate that they are peraluminous,high potassium calc-alkaline I-type granites with adakitic *** intrusions underwent weak crustal assimilation during *** in situ zirconε(Hf)(t)valu.s.of the Xishanyi granodiorites range from-26.4 to-21.8,with T(DM2)model ages of 2552 to 2841 *** in situ zirconε(Hf)(t)valu.s.of the Jianshan granite are from-27.5 to-23.0 with T(DM2)model ages of 2632 to 2904 *** peak age of inherited zircon grains from the Xishanyi granodiorite and the Jianshan granite were^2.07 Ga and^1.94 Ga,*** compared with the regional magmatism,we suggest that both the Xishanyi and Jianshan granitoid intrusions were derived from partial melting of the NCC lower crust.

关键词： Granitoid intrusion Petrogenesis Feidong district Tan-Lu Fault Zone

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spatial distribution of soil salinization under the influence of human activities in arid areas,China

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Journal of Arid Land 2024年第10期16卷 1344-1364页

作者： LIu Yufang YANG Qingwen PEI Xiangjun LI Jingji WANG shuangcheng HuANG Zhenfu HAN Wei ZHENG Tianiang College of Ecology and Environment Chengdu University of TechnologyChengdu 610059China Tianfu Yongxing Laboratory Chengdu 610213China Hydrogeological and Engineering geological Team of Xinjiang Bureau of Geo-Exploration&Mineral Development Changji 831100China

The Hotan Prefecture of Xinjiang uygur Autonomous Region,China belongs to arid desert climate,with significant soil salinization *** study selected six rivers in Hotan Prefecture(Pishan,Qaraqash,Yurungqash,Celle,Kriya,and Niya rivers)to explore the spatial distribution of soil salinization in this area and its underlying *** was conducted along each river's watershed,from the Gobi in the upper reaches,through the anthropogenic impact area in the middle reaches,to the desert area in the lower *** physical-chemical indicators,including total soluble salts,pH,K+,Na+,Ca2+,Mg2+,sO42-,Cl-,CO32-,HCO3-,organic matter,available nitrogen,available phosphorus,and available potassium,were tested,along with the total dissolved solids of surface water and *** results revealed that the soil water and nutrient contents in anthropogenic impact area were higher than those in Gobi and desert areas,while the pH and total soluble salts were lower than those in Gobi and desert *** ions in the soil of the study area were primarily Cl-,sO42-,K+,and Na+,and the ion concentration of soil salt were positively correlated with surface water and ***,the study area exhibited low soil water content,low clay content,infertile soil,and high soil salinization,dominated by weak to moderate chloride-sulfate *** with Gobi and desert areas,the soil in anthropogenic impact area had higher soil water content,lower pH,lower soluble salts,and higher nutrients,indicating that human farming activities help mitigate *** findings have practical implications for guiding the scientific prevention and control of soil salinization in the arid areas and for promoting sustainable agricultural development.

关键词： soil salinization human activities spatial distribution Hotan Prefecture soil soluble salt soil nutrient

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Effect of modeling factors on the dissolution-diffusion-convection process during CO2 geological storage in deep saline formations

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Frontiers of Earth science 2013年第2期7卷 238-256页

作者： WeiZHANG National geological Library of China (Geoscience Documentation Center) China Geological Survey Beijing 100083 China

It is well known that during CO2 geological storage, density-driven convective activity can significantly accelerate the dissolution of injected CO2 into water. This action could limit the escape of supercritical CO2 from the storage formation through vertical pathways such as fractures, faults and abandoned wells, consequently increasing permanence and security of storage. First, we investigated the effect of numerical perturbation caused by time and grid resolution and the convergence criteria on the dissolution-diffusion-convection （DDC） process. Then, using the model with appropriate spatial and temporal resolution, some uncertainty parameters investigated in our previous paper such as initial gas saturation and model boundaries, and other factors such as relative liquid permeability and porosity modification were used to examine their effects on the DDC process. Finally, we compared the effect of 2D and 3D models on the simulation of the DDC process. The above modeling results should contribute to clear understanding and accurate simulation of the DDC process, especially the onset of convective activity, and the CO2 dissolution rate during the convection-dominated stage.

关键词： climate change carbon dioxide geologic sequ.s.ration density-driven convection reactive transport modeling grid resolution

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Triassic magmatism in the eastern part of the south China Block： Geochronological and petrogenetic constraints from Indosinian granites

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Geoscience Frontiers 2017年第3期8卷 445-456页

作者： Wanli Gao Zongxiu Wang Chunlin Li Key Lab of shale Oil and Gas geological survey Institute of GeomechanicsChinese Academy of Geological Science

The granitic dykes in the Badu Group, Zhejiang Province, south China provide important insights on tectonic setting and crustal evolution of the south China Block （sCB） and the Indochina Block during Triassic. Here we report LA-ICP-Ms u-Pb data of granitic rocks from the Hucun and Kengkou which show early Triassic ages of 242 ± 2 and 232 ± 3 Ma, respectively, representing their timing of emplacement. The dyke rocks are enriched in K, AI, LREE, Rb, Th, u, and Pb, and are depleted in Nb, Ta, st, and Ti. The rocks are characterized by highly fractionated REE patterns with （La/Yb）N ratios of 28.46 -38.07 with strong negative Eu anomalies （Eu/Eu＊ = 0,65-0.73）. In situ Hf isotopic analyses of zircons from the Hucun granite yielded CHf（t） valu.s.of -13.9 to -6.4 and two-stage depleted mantle Hf model ages of 1.68-2.15 Ga, which indicate that the magma was formed by partial melting of the Paleo- proterozoic metasedimentary protoliths in the Cathaysia Block. The zircons from the Kengkou granite have eHf（t） valu.s.ranging from -40.7 to 31.5 and yield two-stage depleted mantle Hf model ages of 0.99 -2.49 Ga, indicating magma origin from a mixed source. The Hucun and Kengkou dykes, together with the Triassic A-type granites in sE China were probably generated during magmatism associated with crust-mantle decoupling along the convergent plate boundary between sCB and the Indochina Block.

关键词： Granitic dykes Geochronology Geochemistry lndosinian Eastern south China Block

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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 China Information Center of Ministry of Land and Resources Beijing China geological survey of Henan Province and Institute of geological Research of Henan Province Zhengzhou China geological Institute China Seismological Bureau Beijing China geological survey Institute of Qinghai Province Xining China China university of Geosciences Wuhan 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.

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Geochronology and Petrogenesis for the Protolith of Biotite Plagioclase Gneiss at Lianghe,Western Yunnan

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Acta Geologica sinica(English Edition) 2011年第4期85卷 870-880页

作者： CONG Feng LIN shiliang ZOu Guangfu XIE Tao LI Zaihui TANG Fawei PENG Zhimin Chengdu Center of China geological survey Chengdu 610081China

In this paper,we report an integrated study of u-Pb age and Hf isotope compositions of zircons from biotite plagioclase gneiss at Lianghe in western *** zircons preserved inherited core and rim *** zircon grains and rims yielded a weighted mean ^（206）Pb/^（238）u age of 120.4±1.7 Ma,theirε_（Hf）（120 Ma）valu.s.were mainly negative ranging from-13.9 to-10.7,with Hf model ages between 1.9 Ga and 2.0 Ga,some zircons had positiveε_（Hf）（120 Ma）valu.s.ranging from 0.2 to *** inherited cores showed the wide variations in the u-Pb age of 375-1315 *** of them showed theε_（Hf）（506 Ma）value of-4.2,it was similar to the gray gneiss of old crust,whichε_（Hf）（500 Ma） valu.s.were negative ranging from-4.5 *** geological feature and geochemical data,we concluded that the protolith of biotite plagioclase gneiss was old crust-derived tonalitic magma during the early Cretaceous.

关键词： zircon u-Pb age Hf isotope Lianghe western Yunnan

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K-Ar Ages and Pb,sr Isotopic Characteristics of Cenozoic Volcanic Rocks in shandong Province,China

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Acta Geochimica 1985年第4期4卷 311-324页

作者：陈道公彭子成 MARVINA.LANPHERE ROBERTE.ZARTMAN Department of Earth and space science university of science and Technology of China Department of Earth and space science university of science and Technology of China u. s. geological survey Menlo Park California 94025 usA u. s. geological survey Denrer Colorado 80225 usA

28 samples of Cenozoic volcanic rocks collected from shandong Province have been datedby K-Ar method. They are mainly Neogene with an age range of 4-19 m. y. The basalts fromLinqu and Yishui in west shandong Province are Miocene and those from Penglai and Qixiain east shandong Province are Miocene and Pliocene in age. The basalts from Wudi in northshandong Province are Middle-Early Pleistocene in age. In each area the duration of volcaniceruption was estimated at about 2-3 m. y. Pb and sr isotopic compositions and u, Th, Pb, Rb, sr, and major elements in most ofthe samples were determined. The isotopic compositions are:206Pb/204Pb——16.92-18.48.207Pb/204Pb——15.30-15.59,208Pb/204Pb——37.83-38.54, and (87sr/86sr)i——*** are some positive or negative linear correlations between206Pb/204Pb and207Pb/204Pb,Ph isotopes and Pb content, Pb isotopes and sr isotopes, and sr isotopes and other *** basaltic rocks from east and west shandong Province have somewhat differences inisotopic composition and element content. The basalts probably are products of multi-stageevolution of the mantle. They have preserved the primary features of the source, althoughthey were influenced, to some extent, by the contamination of crustal materials.

关键词： Pb sr K-Ar Ages and Pb,sr Isotopic Characteristics of Cenozoic Volcanic Rocks in shandong Province,China

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