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Enrichment characteristics and sources of the critical metal yttrium in Zhijin rare earth-containing phosphorites, Guizhou Province, China

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Acta Geochimica 2021年第3期40卷 441-465页

作者： Xingxiang Gong Shengwei Wu Yong Xia Zhengwei Zhang Shan He Zhuojun Xie Jiafei Xiao Haiying Yang Qingping Tan Yi Huang Yuhong Yang Institute of Geochemistry Chinese Academy of SciencesGuiyang 550081China University of Chinese Academy of Sciences Beijing 100049China Technology Innovation Center of Mineral ResourcesExplorations in Bedrock Zones Ministry of Natural ResourcesGuiyang 550081China Reserve Bureau of Land and Mineral Resources of Guizhou Province Guiyang 550081China School of Earth Sciences Yunnan UniversityKunming 650500China

Yttrium(Y)is a critical metallic element that is used widely in modern scientific,technological,and industrial applications.Phosphorites in the Zhijin area of Guizhou Province,China,are famous for Y enrichment,but the enrichment characteristics and sources remain unclear.Previous studies suggested that the sources of rare earth elements(REEs,La-Lu)and Y(REYs,La-Lu+Y)were related to hydrothermal deposition.However,this study presents evidence refuting that hypothesis,with major and trace elemental data collected with quadrupoleinductively coupled plasma-mass spectrometry(Q-ICPMS)analysis.These data show that Y in Zhijin REYscontaining phosphorites has a normal distribution and is particularly enriched relative to other REYs.The Y enrichment degree is different at different∑REY intervals.Specifically,the Y enrichment degree is higher at lower∑REY values and lower at higher∑REY values.The REYs-containing phosphorites show features of primary phosphorites.Both REEs and Y have good correlations with P2 O5 in the phosphorites with low REYs contents(total REYs535 ppm),REEs have a good correlation with P2 O5 but Y does not.Inconsistent enrichment processes of REYs are suggestive of complex sources of Y.Thus,seafloor hydrothermal fluids were not the direct source of Y.Normal seawater mixed with terrestrial sources might have contributed to the origin of Y here.This study could lead to improvements in Y mineral resource explorations and the situation involving the global REYs supply crisis.

关键词： Yttrium Phosphorites Rare earth elements trace elements Enrichment processes

Elemental characteristics and paleoenvironment reconstruction： a case study of the Triassic lacustrine Zhangjiatan oil shale, southern Ordos Basin, China

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Acta Geochimica 2018年第1期37卷 134-150页

作者： Delu Li Rongxi Li Zengwu Zhu Xiaoli Wu Futian Liu Bangsheng Zhao Jinghua Cheng Baoping Wang School of Earth Sciences and Resources Chang'an University Xi'an 710054 China Shaanxi Center of Geological Survey Xi'an 710068 China Yanchang Oilfiled Co. Ltd Yah'an 716000 China

Using trace elements to reconstruct paleoenvironment is a current hot topic in geochemistry. Through analytical tests of oil yield, ash yield, calorific value, total sulfur, major elements, trace elements, and X-ray diffraction, the quality, mineral content, occurrence mode of elements, and paleoenvironment of the Zhangjiatan oil shale of the Triassic Yanchang Formation in the southern Ordos Basin were studied. The analyses revealed relatively high oil yield(average 6.63%) and medium quality. The mineral content in the oil shale was mainly clay minerals,quartz, feldspar, and pyrite; an illite–smectite mixed layer comprised the major proportion of clay minerals. Compared with marine oil shale in China, the Zhangjiatan oil shale had higher contents of quartz, feldspar, and clay minerals, and lower calcite content. Silica was mainly in quartz and Fe was associated with organic matter, which is different from marine oil shale. The form of calcium varied. Cluster analyses indicated that Fe, Cu, U, V, Zn, As,Cs, Cd, Mo, Ga, Pb, Co, Ni, Cr, Sc, P, and Mn are associated with organic matter while Ca, Na, Sr, Ba, Si, Zr, K,Al, B, Mg, and Ti are mostly terrigenous. Sr/Cu, Ba/Al, V/(V+ Ni), U/Th, AU, and δU of oil shale samples suggest the paleoclimate was warm and humid, paleoproductivity of the lake was relatively high during deposition of the shale—which mainly occurred in fresh water—and the paleo-redox condition was dominated by reducing conditions. Fe/Ti ratios of the oil shale samples suggest clear hydrothermal influence in the eastern portion of the study area and less conspicuous hydrothermal influence in the western portion.

关键词： trace elements Occurrence mode Paleoenvironment Zhangjiatan oil shale Yanchang Formation Ordos Basin

Source characteristics and genesis of Sb mineralization from the Au and Sb deposits of the Youjiang Basin,SW China:constraints from stibnite trace element and isotope geochemistry

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Acta Geochimica 2021年第5期40卷 659-675页

作者： Aizat Zhaanbaeva Keqiang Peng Abiola Oyebamiji Kyiazbek Asilbekov State Key Laboratory of Ore Deposit Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China University of Chinese Academy of Sciences Beijing 100049China Institute of Geology of National Academy of Sciences of Kyrgyz Republic Bishkek 720000Kyrgyzstan

The Youjiang Basin is characterized by a wide distribution of Au and Sb deposits.These deposits are mainly hosted by sedimentary rocks from Cambrian to Triassic and are structurally controlled by faults and folds.Three types of Sb mineralization can be distinguished based on geologic characteristics,economic metals,and mineral associations.The first type is dominated by Sb mineralization but contains minor or little Au,similar to the large Qinglong deposit.The second type has a spatial association with the gold deposit but formed independent Sb mineralization,reminiscent of the Badu deposit.In the third type,Sb generally formed as an accompanying element in the Carlin-type gold deposit,and stibnite occurred as euhedral crystals filling the open space and faults in the late stage of gold mineralization,analogous to the Yata deposit.trace element concentrations and sulfur isotopic ratio of stibnite,and oxygen isotope of stibnite bearing quartz were analyzed to infer the ore source(s)for Sb mineralization and genesis.To distinguish the various types of stibnite mineralization between the deposits,Cu,Pb,and As have recognized most diagnostic,with an elevated concentration in Au and Au-Sb deposits and depleted in Sb deposit.Theδ34S isotopic composition of stibnite samples from three deposits show a wide variation,ranging from-6.6%to+17.45%.Such isotopic values may indicate the sedimentary sulfur source,introduced by fluid–rock interaction.On the other hand,fluid mixing of several end members cannot be excluded.The calculatedδ18O isotopic data of Sb-bearing quartz show the initial ore fluid in Au and Au-Sb deposits most likely have a magmatic or metamorphic origin that enriched during fluid–rock interaction,and Sb deposit characterized by initial meteoric water.From these data,we proposed that different lithologies,fluid–rock interaction,fluid pathways,and different ore fluids controlled the compositional evolution of fluids,which might be the main reason for the diversity of Au or Sb mineralization.

关键词： trace elements Stable isotope Sb mineralization Youjiang Basin SW China

An evaluation of the emission profile for two-wheelers at a traffic junction

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Particuology 2015年第1期13卷 112-119页

作者： Avinash Kumar Agarwal Prakhar Bothra Tarun Gupta Pravesh Chandra Shukla Engine Research Laboratory Department of Mechanical EngineeringIndian Institute of Technology Kanpur Department of Civil Engineering Indian Institute of Technology Kanpur

Two-wheeler vehicles are an important mode of transportation in developing countries. However, the emissions from two-wheeler vehicles are significant. Urban two-wheeler vehicles with gasoline-fueled engines produce NOx and particulate matter emissions that affect urban air quality. During traffic light stops and programmed stops, for instance, pollutants are emitted and are dangerous to human health. In this experimental study, two-wheeler vehicles with different makes, technologies and engine capacities were tested for exhaust emissions including gravimetric and online measurements at different engine speeds and a no load condition at a simulated traffic junction. Gravimetric measurements were performed by collecting the particulate mass （at two engine speeds： 1500 and 2500 rpm） from a diluted engine-out exhaust on quartz filter paper. Next, these collected particulates were used to determine the presence of metals, as well as the benzene soluble organic fraction （BSOF）. The total particulate mass, BSOF and trace elements were slightly higher at a higher engine speed （2500 rpm）. Online measurements were performed by sampling the engine exhaust （at four engine speeds： 1500, 2000, 2500, and 3000rpm） and using online instruments to determine the particle number and size distribution, the particle-bound polyaromatic hydrocarbons （PAHs）, the gaseous emissions and the smoke opacity. Engines with higher cubic capacity emitted a higher concentration of nano-particles. The particle-bound PAH concentration increased as the engine speed increased, but this concentration was notably low for the highest engine speed tested （3000 rpm）. The regulated gaseous emissions increased as the engine speed increased for all vehicles.

关键词： Benzene soluble organic fraction （BSOF） Particle number and size distribution trace elements Polyaromatic hydrocarbons （PAHs） Regulated gaseous emissions

trace and rare earth element geochemistry of the black and grey shales of the Calabar Flank, Southeastern Nigeria: constraints on the depositional environment and the degree of metal enrichment

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Acta Geochimica 2021年第3期40卷 312-324页

作者： Christopher Iorfa Adamu Benjamin Odey Omang Oluwaseye Peter Oyetade Otu Johnson Therese Ntonzi Nganje Department of Geology Faculty of Physical ScienceUniversity of CalabarCross River StateNigeria Department of Geology Faculty of ScienceUniversity of BeninEdo StateNigeria

This study focuses on the trace and rare earth elements(REE)geochemistry of the Nkporo and Ekenkpon Shales of the Calabar Flank.The main aim is to infer their depositional environment and the degree of their metal enrichment.The shale samples were analyzed using inductively coupled plasma mass spectrometry.The results indicated that the mean concentrations of K,Na,and Fe in Nkporo and Ekenkpon Shales are 1.45,0.4,and 4.17 wt%,and 1.11,0.44,and 5.42 wt%;respectively.The Nkporo Shale is enriched with the following trace elements;P>Mn>Sr>Ba>Zn>Ce>Rb>Zr>V>Cr>Ni and depleted in the following trace elements;Ta>Ge>Sb>Bi>Cd>Ag>Te>In>Hg.While the Ekenkpon Shale is enriched with the following trace elements;P>Mn>Ba>Sr>V>Ce>Zr>Rb>Cr>Zn>Ni and depleted in;Sb>Ge>Bi>Ag>Ce>Te>In>Hg.The concentration of redox-sensitive elements such as V,Ni,Mo,U,Cu,Cr,Re,Cd,Sb,Ti,Mn,and their ratio V/Mo and U/Mo in the black and grey shale samples show different patterns.The REE obtained from the Nkporo and Ekenkpon Shales were PAAS normalized.The Nkporo Shale showed a slightly flat light rare-earth element(LREE),middle rare-earth element(MREE),and heavy rare earth element(HREE)pattern enrichment.Ce/Ce*ranges from 0.95 to 1.09 in Nkporo Shale and 0.67 to 1.40 in Ekenkpon Shale.The Ekenkpon Shale showed a slight LREE,MREE enrichment,and depleted HREE patterns.The Mn contents and U/Mo ratio in Nkporo and Ekenkpon Shales suggests a poor oxygen transitional environment.The V/Mo and V/(V+Ni)ratios indicated that the Nkporo shales were deposited in an anoxic to suboxic conditions and Ekenkpon shales were also deposited under an anoxic to suboxic conditions.The V/Ni ratio indicated that the organic matter in the Nkporo shale is terrigenous while that of the Ekenkpon shales are both terrigenous and marine in origin.

关键词： Rare-earth elements(REE) trace elements Calabar Flank Suboxic Anoxic

Multi-trace Element and Rare Earth Element Composition of Coastal Casuarina Equisetifolia Ecosystem in Hainan Island,China

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Journal of Rare Earths 2003年第S1期21卷 219-224页

作者：刘强毕华黄澜彭少麟 South China Institute of Botany Chinese Academy of Sciences Geology Department Hainan Normal University Biology Department Hainan Normal University

46 trace elements including 14 rare earth elements (REEs) in coastal Casuarina equisetifolia plant-soil system from 9 sampling sites in Hainan Island were detected by using ICP-MS. The aim is to explore the biogeochemical characteristics of migration and translocation of trace elements in soil-plant system and their function on the changes of environmental geochemistry. The results indicate that multi-trace elements in coastal sandy soil in Hainan Island are at very low level. The multi-element patterns are quite similar among plant,sandy soil and upper continental crust (UCC),and the magnitudes of trace element concentrations among them are different in the general order of planttrace element concentrations with 1～2 orders of magnitudes less than those of the average UCC,while plant has 1～3 orders of magnitudes less than UCC and 1～2 orders less than the soil. The total trace element contents are not significantly different between root and needle,but significantly different between branch and root and between branch and needle. Those of root or needle are about 2 times of those of branch. Ag,Cd,In,Sn and Tl are enriched in C. equisetifolia,especially Ag.

关键词： trace elements Casuarina equisetifolia coastal ecosystem rare earths

Association of Urinary Strontium Levels with Pregnancy-induced Hypertension

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Current Medical Science 2021年第3期41卷 535-541页

作者： Yi TANG Wei XIA Shun-qing XU Hong-xiu LIU Yuan-yuan LI Key Laboratory of Environment and Health(HUST) Ministry of Education&Ministry of Environmental Protectionand State Key Laboratory of Environmental Health(Incubation)School of Public HealthTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China

Pregnancy-induced hypertension(PIH),including gestational hypertension and preeclampsia,accounts for the majority of maternal and perinatal morbidity and mortality.Strontium(Sr)has been recently associated with preeclampsia in a small group of women;however,the role of Sr in PIH is not fully understood and warrants further investigation.In this study,we examined the association between urinary Sr levels and PIH,and assessed the effect of maternal age on the association.Urinary Sr concentrations were measured in 5423 pregnant women before delivery by inductively coupled plasma mass spectrometry(ICP-MS).Logistic regression analysis adjusting for potential confounders was applied to explore the association between Sr and PIH,and to evaluate the Sr-PIH relationship stratified by maternal age.Among the participants,200(3.83%)women were diagnosed with PIH.Compared with non-PIH women,women who developed PIH had lower urinary Sr concentrations(131.26 us.174.98μg/L creatinine,P<0.01).With the natural log-transformed urinary creatinine-standardized Sr concentrations increasing,the risk of PIH decreased significantly[adjusted OR=0.60(95%CI:0.51,0.72)].Furthermore,the significant association of Sr with PIH was found among women under 35 years(P<0.01).Our finding suggested that Sr may play a potential protective role in the pathogenesis of PIH,especially among young pregnant women under 35 years old.

关键词： strontium pregnancy hypertension maternal age trace elements

Current understanding of the metabolism of micronutrients in chronic alcoholic liver disease

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World Journal of Gastroenterology 2020年第31期26卷 4567-4578页

作者： Jing Wu Qing-Hua Meng Department of Critical Care Medicine of Liver Disease Beijing You-An HospitalCapital Medical UniversityBeijing 100069China

Alcoholic liver disease(ALD)remains an important health problem worldwide.Perturbation of micronutrients has been broadly reported to be a common characteristic in patients with ALD,given the fact that micronutrients often act as composition or coenzymes of many biochemical enzymes responsible for the inflammatory response,oxidative stress,and cell proliferation.Mapping the metabolic pattern and the function of these micronutrients is a prerequisite before targeted intervention can be delivered in clinical practice.Recent years have registered a significant improvement in our understanding of the role of micronutrients on the pathogenesis and progression of ALD.However,how and to what extent these micronutrients are involved in the pathophysiology of ALD remains largely unknown.In the current study,we provide a review of recent studies that investigated the imbalance of micronutrients in patients with ALD with a focus on zinc,iron,copper,magnesium,selenium,vitamin D and vitamin E,and determine how disturbances in micronutrients relates to the pathophysiology of ALD.Overall,zinc,selenium,vitamin D,and vitamin E uniformly exhibited a deficiency,and iron demonstrated an elevated trend.While for copper,both an elevation and deficiency were observed from existing literature.More importantly,we also highlight several challenges in terms of low sample size,study design discrepancies,sample heterogeneity across studies,and the use of machine learning approaches.

关键词： Alcoholic liver disease Metabolism trace elements Vitamins Malnutrition Oxidative stress

A multiple-proxy stalagmite record reveals historical deforestation in central Shandong, northern China

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Science China Earth Sciences 2020年第11期63卷 1622-1632页

作者： Liangcheng TAN Wen LIU Tianli WANG Peng CHENG Jingjie ZANG Xiqian WANG Le MA Dong LI Jianghu LAN R.Lawrence EDWARDS Hai CHENG Hai XU Li AI Yongli GAO Yanjun CAI State Key Laboratory of Loess and Quaternary Geology Institute of Earth EnvironmentChinese Academy of SciencesXi’an 710061China Center for Excellence in Quaternary Science and Global Change Chinese Academy of SciencesXi’an 710061China Institute of Global Environmental Change Xi’an Jiaotong UniversityXi’an 710049China Open Studio for Oceanic-Continental Climate and Environment Changes Pilot National Laboratory for Marine Science and TechnologyQingdao 266061China 801 Institute of Hydrogeology and Engineering Geology Shandong Provincial Bureau of Geology&Mineral ResourcesJinan 250014China Shandong Engineering Research Center for Environmental Protection and Remediation on Groundwater Jinan 250014China Library of Chang’an University Xi’an 710064China Department of Earth Sciences University of MinnesotaMinneapolis MN 55455USA School of Geography Nanjing Normal UniversityNanjing 210097China Institute of Surface-Earth System Science Tianjin UniversityTianjin 300072China Department of Geological Sciences University of Texas at San AntonioSan Antonio TX 78249USA

Evaluating anthropogenic impacts on regional vegetation changes during historical time is not only important for a better understanding of the Anthropocene but also valuable in improving the vegetation-climate models.In this study,we analyzed stable isotopes(δ^18O,δ^13C)and trace elements(Mg/Ca,Sr/Ca)of a stalagmite from Huangchao Cave in central Shandong,northern China.230Th and AMS14C dating results indicate the stalagmite deposited during 174BC and AD1810,with a hiatus between AD638 and 1102.Broad similarities of theδ^18O and trace elements in the stalagmite suggest they are reliable precipitation indexes.Theδ^13C of the stalagmite,a proxy of vegetation change,was generally consistent with local precipitation and temperature variations on a centennial-scale before the 15th century.It typically varied from–9.6‰to–6.3‰,indicating climate controlled C3 type vegetation during this period.However,a persistent and marked increasing trend in theδ^13C record was observed since the 15th century,resulting inδ^13C values from–7.7‰to–1.6‰in the next four centuries.This unprecedentedδ^13C change caused by vegetation deterioration cannot be explained by climate change but is fairly consistent with the dramatically increasing population and farmland in Shandong.We suggest that the increasing deforestation and reclamation in central Shandong began to affect vegetation in the mountain region of central Shandong since the 15th century and severely destroyed or even cleared the forest during the 16th–18th century.

关键词： Speleothem Stable isotopes trace elements Deforestation Human activity 16th century