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Seasonal and spatial variations in rare earth elements and yttrium of dissolved load in the middle,lower reaches and estuary of the Minjiang River,southeastern China 被引量:1
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作者 ZHU Xuxu GAO Aiguo +5 位作者 LIN Jianjie JIAN Xing YANG Yufeng ZHANG Yanpo HOU Yuting GONG Songbai 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2018年第3期700-716,共17页
A bstract With the aim of elucidating the spatial and seasonal behaviors of rare earth elements(REEs), we investigated the dissolved REE concentrations of surface water collected during four seasons from middle, lower... A bstract With the aim of elucidating the spatial and seasonal behaviors of rare earth elements(REEs), we investigated the dissolved REE concentrations of surface water collected during four seasons from middle, lower reaches and estuary of the Minjiang River, southeastern China. The results display that the REE abundances in Minjiang River, ranging from 3.3–785.9 ng/L, were higher than those of many of the major global rivers. The total REE concentrations(∑REE) were seasonally variable, averaging in 5 937.30, 863.79, 825.65 and 1 065.75 ng/L during second highest flow(SHF), normal flow(NF), low flow(LF) and high flow(HF) season, respectively. The R_(( L/M)) and R_((H/M)) ratios reveal the spatial and temporal variations of REE patterns, and particularly vary apparently in the maximum turbidity zone and estuary. REE patterns of dissolved loads are characterized by progressing weaker LREEs-enrichment and stronger HREEsenrichment downstream from middle reaches to estuary during all four seasons. Comparing with NF and LF seasons, in which REE patterns are relatively flat, samples of SHF season have more LREE-enriched and HREE-depleted patterns that close to parent rocks, while samples of HF season are more LREEs-depleted and HREE-enriched. REE fractionations from the middle to lower reaches are stronger in the SHF and HF seasons than those in NF and LF seasons. Generally, spatial and seasonal variations in REE abundance and pattern are presumably due to several factors, such as chemical weathering, mixture with rainfall and groundwater, estuarine mixing, runoff, biological production and mountain river characters, such as strong hydrodynamic forces and steep slopes. The highest Gd/Gd* always occurs at north ports during all four seasons, where most of the large hospitals are located. This suggests Gd anomalies are depended on the density of modern medical facilities. Y/Ho ratios fl uctuate and positively correlate to salinity in estuary, probably because of the geochemical behavior differences between Y and Ho. 展开更多
关键词 rare earth elements(rees) Minjiang River estuarine mixing process dissolved load online pre-concentration system
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Ion Probe Study of Silicate Inclusions from Colomera (IIE) Iron Meteorite: the Rare Earth Element Perspective
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作者 HSU Weibiao 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2004年第5期1060-1074,共15页
Coupled with a petrographical study, I carried out an ion probe study of rare earth element microdistributions in mineral phases of silicate inclusions from the Colomera ⅡE iron meteorite. Most mineral grains have ho... Coupled with a petrographical study, I carried out an ion probe study of rare earth element microdistributions in mineral phases of silicate inclusions from the Colomera ⅡE iron meteorite. Most mineral grains have homogeneous REEs, but show considerable inter-grain variations by a factor of 2 to 100. The whole rock REE abundances for Colomera, estimated by combining REE data with modal abundances, are relatively LREE-enriched with REEs of -10'CI, which suggest that Colomera silicates were highly differentiated and might represent a low degree partial melt (-10%) of a chondritic source. REE geochemistry of Colomera silicate inclusions points to an origin that involves differentiation, dynamic mixing, remelting, reduction, recrystallization, and subsequent rapid cooling near the surface of a planetary body. 展开更多
关键词 ion probe rare earth elements Colomera silicate inclusions ⅡE iron meteorites
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Zircon deposit and rare earth element enriched metasomatic alkaline rocks at Kyemyeongsan Formation, Chungju, Korea: Paleozoic magmatism and Zr-REE-Nb mineralization
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作者 Maeng Eon Park (Department of Environmental Geosciences, Pukyong National University, Pusan 608 737, Korea) Gun Soo Kim (Department of Geology, Pusan National University, Pusan 609 735, Korea) 《Global Geology》 1999年第1期61-73,共13页
The zircon ore deposit in metasediments and peralkaline granite of the Kyemyeongsan Formation is located in southwest of Chungju city, Korea. The deposit, closely associated with REE and Nb,is composed of metasomatic ... The zircon ore deposit in metasediments and peralkaline granite of the Kyemyeongsan Formation is located in southwest of Chungju city, Korea. The deposit, closely associated with REE and Nb,is composed of metasomatic alkaline rocks and rare metal alkali granite, and was formed in late Carboniferous (340~343Ma). Zircon occurs in different paragenetic sequence: (1) earlier rare metal alkali granite, (2) later metasomatic zircon ore. The metasomatic zone contains abundant microcline, albite and quartz with minor biotite, magnetite, hornblende, allanite and zircon. The alkali granites have high silica (72.13~74.52wt.% as SiO 2), and total iron content (5.95~6.89%), and are characterized by low Al 2O 3 content (7.12~9.74%). They also show variable K 2O content (3.60~6.98%), and high ratios of K 2O/Na 2O. The REE patterns of rare metal alkali granite are similar to those of felsic volcanics from rifts, or back arc basins in, or near continental crust. Zircon ores are characterized by high iron content and low Al 2O 3, SiO 2, and K 2O content and have unusually high total REE content (0.18~2.33%). REE patterns show relatively flat to somewhat heavy REE (HREE) depleted characteristics (Ce/Yb=0.39~5.17) with large Eu negative anomaly (Eu/Eu *=0.16~0.29). Laser ablation microprobe inductively coupled plasma mass spectrometer (LAM ICP MS) analyses has been carried on zircon. The REE patterns of mineral zircons are almost the same to those of zircon ores and rare metal alkali granites, which may reflect the inability of zircons to effectively fractionated REE at formation of origin. The Sm Nd isochron age of the zircon ore and rare metal alkali granite are 330Ma, and 331Ma, respectively with ε Nd(t) being range from -2.00 to -1.84. This data suggest that the ore forming material came from the mantle. Alkali granite has suffered extensive post magmatic metasomatism of a high temperature to produce zircon ores. Geochemical characteristics show that metasomatism of alkaline fluid was probably the dominant ore forming process in Chungju district. 展开更多
关键词 ree Zircon deposit and rare earth element enriched metasomatic alkaline rocks at Kyemyeongsan Formation Chungju Korea ZR
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Rare Earth Elements in Zhijin Phosphorite and Distribution in Two-Stage Flotation Process 被引量:3
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作者 李军旗 金会心 +1 位作者 陈跃 毛小浩 《Journal of Rare Earths》 SCIE EI CAS CSCD 2007年第S1期85-90,共6页
Zhijin phosphorite is one of super large-scale medium-low grade and REE-bearing phosphorite deposit in Southwest of China. Previous investigations had revealed that this deposit contained appreciable amounts of rare e... Zhijin phosphorite is one of super large-scale medium-low grade and REE-bearing phosphorite deposit in Southwest of China. Previous investigations had revealed that this deposit contained appreciable amounts of rare earth elements (REE) reaching up to 1300 μg·g-1. In this paper, REE contents and existing state in single collophanite and dolomite mineral were further analyzed by ICP-MS and EPMA-1600 Electric Probe methods. The results indicated that REE content of collophanite was far more than that of dolomite, and increased with an increase of phosphor. There existed independent minerals of REE in single collophanite mineral, such as cerianite and monazite, but the amount of them was extremely little. No independent mineral of yttrium was found in this investigation. Presumedly, REE and yttrium were present in the form of ions in the lattices of collophanite. Based on above investigation, the two-stage reverse flotation technology was carried out to see the distribution of REE in flotation process. It was found that REE was mainly enriched in phosphate concentrate and recovered in the rough stage flotation. REE recovery of concentrate increased with an increase of P2O5 content and P2O5 recovery of concentrate. Under the optimum flotation condition, REE recovery was 79.25% in the rough stage flotation and 9.94% in scavenging flotation. 展开更多
关键词 rare earth elements PHOSPHORITE distribution of ree FLOTATION rare earths
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Rare earth element content in the SPM of Daliao river system and its comparison with that in the sediments, loess and soils in China 被引量:2
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作者 林春野 何孟常 +3 位作者 李艳霞 杨林生 刘瑞民 杨志峰 《Journal of Rare Earths》 SCIE EI CAS CSCD 2008年第3期414-420,共7页
Content and distribution patterns of rare earth dements (REEs) in the suspended particulate material (SPM) of Daliao River system were investigated and compared with those in the fiver and sea sediments, loess, an... Content and distribution patterns of rare earth dements (REEs) in the suspended particulate material (SPM) of Daliao River system were investigated and compared with those in the fiver and sea sediments, loess, and soils of China. Twenty-seven samples of SPM were taken in Daliao River system and digested with various acids followed by ICP-MS analysis for REEs and ICP-OES analysis for Al, Fe, Mn, Ti, Mg, Ca, Na, and K, to measure the total concentrations of these elements. Results indicated that the spatial change in the content of REEs was great, with the coefficient of variance (CV) from 84% to 105%, while the contents of REEs were significantly correlated with each other. Chondrite-normalized patterns of REEs were characterized by higher enrichment of light REEs than heavy REEs, and a depletion of Eu in the SPM was generally found. The positive anomaly of Eu in the SPM of Xi River was due to anthropogenic source in Shenyang City. Furthermore, chondfite- and upper continent crust-normalized patterns of REEs in the SPM of Daliao River system, sediments of Yangtze River and Yellow River, sediments of Yellow Sea, East Sea, South Sea of China, and loess and soil of China, were very similar to one another. These demonstrated that the weathering and sedimentary processes resulted in constant REE distribution not only in the typical sedimentary rocks, but also in the modem riverine particle, sea sediments, loess, and soils. 展开更多
关键词 rare earth elements rees) suspended particulate material (SPM) distribution pattern Daliao River rare earths
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Geochemistry of rare-earth elements in shallow groundwater, northeastern Guangdong Province, China 被引量:5
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作者 YUAN Jianfei MAO Xumei +2 位作者 WANG Yanxin DENG Zhide HUANG Leihui 《Chinese Journal Of Geochemistry》 EI CAS CSCD 2014年第1期53-64,共12页
Shallow groundwater and hot springs were collected from northeastern Guangdong Province, Southeast China, to determine the concentrations and fractionation patterns of rare-earth elements(REE). The results show that t... Shallow groundwater and hot springs were collected from northeastern Guangdong Province, Southeast China, to determine the concentrations and fractionation patterns of rare-earth elements(REE). The results show that the La, Ce and Nd of REEs are abundant in groundwater and rock samples, and the ∑REE contents in groundwater and rock samples range from 126.5 to 2875.3 ng/L, and 79.44 to 385.85 mg/L, respectively. The shallow groundwater has slightly HREE-enriched PAAS-normalized patterns. However, the granitic rocks PAAS-normalized patterns, with remarkable negative Eu anomalies, are different from that of shallow groundwater. The enrichment of HREE is considered to be controlled by REE complexation and readsorption for most groundwater has Ce and Eu positive anomalies. The Ce and Eu anomalies in groundwater are controlled by redox conditions. Moreover, the Fe-contain sediments dissolution and/or the reduction of Fe oxyhydroxides are another factor contributing to Ce anomalies. The Eu anomalies in groundwater are controlled by the preferential mobilization of Eu2+ during water-rock interaction compared to Eu3+. 展开更多
关键词 浅层地下水 稀土元素 中国东南部 地球化学 粤东北 氧化还原条件 地下水控制 Ce异常
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Distribution pattern and geochemical analysis of rare earth elements in deep-ocean sediments 被引量:2
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作者 Jingxi LI Chengjun SUN +2 位作者 Fenghua JIANG Fenglei GAO Yifan ZHENG 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2021年第1期79-88,共10页
The content and distribution pattern of rare earth elements(REEs)in surface sediments from the Eastern and Western Pacifi c Ocean,the Northern and Southern Atlantic Ocean,and the Southwestern Indian Ocean were explore... The content and distribution pattern of rare earth elements(REEs)in surface sediments from the Eastern and Western Pacifi c Ocean,the Northern and Southern Atlantic Ocean,and the Southwestern Indian Ocean were explored and the resources and geochemical characteristics of REEs in deep-ocean sediments from diff erent oceans were studied.The total REE abundances(ΣREE)in the diff erent oceans ranged as follows:Eastern Pacifi c,56.88–500.02μg/g;Western Pacifi c,290.68–439.94μg/g;Northern Atlantic,55.33–154.90μg/g;Southern Atlantic,40.83–69.30μg/g;and Southwestern Indian Ocean,20.24–64.76μg/g.Their corresponding LREE(La-Eu)/HREE(Gd-Lu)average values were 5.18,5.86,9.01,5.21,and 4.59,which indicated that the light REEs were all evidently enriched.δEu andδCe showed slight Eu-negative anomalies and signifi cant Ce-positive anomalies in all sediments.Although the contents of REEs in the sediments varied among the diff erent oceans,the distribution patterns of REEs were similar,and the correlation coeffi cient was greater than 0.9290.In the Eastern Pacifi c sediments,ΣREE showed a signifi cantly positive correlation with Co,Cu,Zn,Mn,Mo and a weak correlation with Fe.In the Western Pacifi c and Southern Atlantic sediments,ΣREE presented no obvious correlation and a weakly negative correlation with Co,Cu,Zn,Mn,Mo and Fe,respectively.ΣREE in the Southwestern Indian Ocean sediments positively correlated with Cu,Zn,Mn,Mo,Fe,and had a weakly negative correlation with Co. 展开更多
关键词 rare earth elements(ree)geochemistry distribution pattern ree fractionation marine sediment
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Geochemical Characteristics of Rare Earth Elements in Guposhan Granite Complex and Their Petrogenetic Implication 被引量:1
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作者 杨学明 张培善 《Journal of Rare Earths》 SCIE EI CAS CSCD 1991年第1期60-65,共6页
In this paper the geochemical characteristics of rare earth elements in Guposhan granite complex in Nanling Area,South China,is systematically studied,and the balance of REE distribution in rock-forming minerals, whic... In this paper the geochemical characteristics of rare earth elements in Guposhan granite complex in Nanling Area,South China,is systematically studied,and the balance of REE distribution in rock-forming minerals, which contain only 21.47~29.71 wt% of total REE in granites,is calculated.The petrogenetic relationship be- tween three different stages of the granites in the complex is discussed,and a geochemical model is suggested for the formation of granitic magma in early stage by partial melting of the crustal basement rocks containing more REE than that in the late stage.It shows that a ion-adsorption type of REE deposit could ocuur in the weath- ering crust on the early stage granite.Rb-Sr isotope isochron dating of the first stage medium-coarse-grained K-feldspar granite shows that its age is 146.5 Ma and initial ^(87)Sr/^(86)Sr ratio is 0.71198. 展开更多
关键词 rare earth elements GRANITE Petrogenetic mechanism Geochemical model Ion-adsorption type ree deposit
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Effect of Anion on Adsorption of Rare Earth Elements on Kaolinite 被引量:1
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作者 万鹰昕 刘建军 《Journal of Rare Earths》 SCIE EI CAS CSCD 2007年第S2期242-245,共4页
For a better understanding the adsorption of rare earth elements(REEs) on minerals and its controlling factors, adsorption experiments were performed with kaolin in a matrix of various concentration of anion (Cl-, ClO... For a better understanding the adsorption of rare earth elements(REEs) on minerals and its controlling factors, adsorption experiments were performed with kaolin in a matrix of various concentration of anion (Cl-, ClO4-, SO42-) in the pH 6.5. The adsorption of REEs onto the kaolin increase with increasing anion concentration, especially in the presence of SO42-, which is ascribe to the Na+ mass effect and anion complexation. furthermore, the heavy REEs are more adsorbed onto kaolin in presence of higher concentration of anion, especially for Cl-and SO42-, presumably due to the difference of anion complexation with light REE and heavy REEs. 展开更多
关键词 rare earth elements (rees) ADSORPTION ANION KAOLINITE
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Experimental Study on Adsorption of Rare Earth Elements on Kaolinite and Halloysite 被引量:1
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作者 GAO Yuhong FAN Chenzi XU Hong 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第S1期80-82,共3页
1 Introduction The weathered crust rare earth deposits is one of the most significant rare earth deposits,which are mostly distributed in southern China,especially in the south of Jiangxi province(Chi et al.,2007).The... 1 Introduction The weathered crust rare earth deposits is one of the most significant rare earth deposits,which are mostly distributed in southern China,especially in the south of Jiangxi province(Chi et al.,2007).The compositions of these deposits,which are weathered from igneous rocks such as granite through biological,physical or chemical 展开更多
关键词 In Experimental Study on Adsorption of rare earth elements on Kaolinite and Halloysite ree than
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Using Geochemistry of Rare Earth Elements to Indicate Sediment Provenance of Sand Ridges in Southwestern Yellow Sea 被引量:5
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作者 LI Lei SU Jinbao +1 位作者 RAO Wenbo WANG Yigang 《Chinese Geographical Science》 SCIE CSCD 2017年第1期63-77,共15页
The Jianggang Harbour-centered radial sand ridge(RSR) is the largest sand body in the Yellow Sea. Its formation and evolution are of interest for scientists of various fields; however, the sediment provenance is uncer... The Jianggang Harbour-centered radial sand ridge(RSR) is the largest sand body in the Yellow Sea. Its formation and evolution are of interest for scientists of various fields; however, the sediment provenance is uncertain. In this study, rare earth element(REE) geochemical compositions of the RSR sediments together with their potential sources are investigated to identify the provenance of the RSR sediments. The typical parameters((La/Yb)_N,(La/Sm)_N and(Gd/Yb)_N) as well as the upper continental crust-normalized patterns of REEs can only be associated with source rocks, and thus can be used as effective tracers for the origin and sources of sediments. However, the REE contents of sediments are affected by many factors, such as particle sorting and chemical weathering. Onshore RSR sediments are different in REE geochemical composition from offshore RSR sediments to some extent, suggesting that not all of the offshore RSR sediments have the same sources as the onshore RSR sediments. Meanwhile, the sediments adjacent to the northeast of Cheju Island and at Lian Island near the Lianyun Harbour were not the source of the RSR sediments due to their distinctive REE patterns, dEu,(La/Yb)_N,(Gd/Yb)_N and(La/Sm)_N. The Korean river sediments could be dispersed to the Jiangsu Coast slightly impacting the fine fractions of the RSR sediments, particularly the offshore RSR sediments. Additionally, geochemical comparisons show that the modern Yellow River was responsible for the onshore RSR sediments, whereas the sediment loads from the Yangtze River could serve as a major contributor to the RSR, particularly the offshore RSR. In addition, the offshore RSR could also be partly fed by an unknown source due to some high values of(La/Yb)_N,(La/Sm)_N and La contents differing from those of the Chinese and Korean river sediments. 展开更多
关键词 rare earth elements(rees) sediment provenance radial sand ridges(RSRs) potential sources Yellow Sea
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Rare earth elements-rich phase and enriching mechanism in sediments from CC area, the Pacific Ocean 被引量:2
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作者 Meng Xianwei, Chen Zhihua, Wang Xiangqin, Liu Na (1. First Institute of Oceanography, State Oceanic Administration, Qingdao 266003, China 2. Key Lab. of Marine Science and Numerical Modelling, State Oceanic Administration, Qingdao 266003, China) 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2001年第2期209-214,共6页
Compared to North American shale composition (NASC), REE contents of sediments from the CC area in the Pacific Ocean are obviously high except that cerium has equal content to that of NASC. Three-valence rare earth el... Compared to North American shale composition (NASC), REE contents of sediments from the CC area in the Pacific Ocean are obviously high except that cerium has equal content to that of NASC. Three-valence rare earth elements were completely enriched in phosphate-phase and cerium in iron-phase. Rare earth elements in the sediments were originally derived from seawater. During lithi- genic and minerogenic processes of metalliferous nodules, three-valence rare earth elements in sediments mobilized and incorporated into sediments as authigenous biogenic-apatite, while cerium had change from Ce3+ to Ce4+ and directly precipitated from seawater and entered metalliferous nodules and caused Ce anomalies in REE pattern in sediments. 展开更多
关键词 CC area of the Pacific Ocean SEDIMENTS rare earth elements ree- rich phase enriching mechanism
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Sources and control factors of rare earth elements in Late Permian mudstones,Southwest China
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作者 肖明国 庄新国 +1 位作者 易炜 毛婉慧 《Journal of Central South University》 SCIE EI CAS 2012年第6期1741-1752,共12页
The material sources and control factors of rare earth elemems (REEs) for 25 borehole bulk samples from the Late Permian Longtan Formation in Mount Huaying (borehole number: ZK10-6), Sichuan Province, South China... The material sources and control factors of rare earth elemems (REEs) for 25 borehole bulk samples from the Late Permian Longtan Formation in Mount Huaying (borehole number: ZK10-6), Sichuan Province, South China, were investigated. All samples were determined by inductively coupled plasma mass spectrometry (ICP-MS). The chondrite-normalized distribution patterns of mudstone samples are uniform. All samples belong to the light rare earth element (LREE)-rich type and are enriched in LREEs relative to heavy rare earth elements (HREEs). The distribution curves of REEs in mudstone are highly similar to Mount Emei basalt and the three periods of REEs enrichment correspond to three Mount Emei basalt eruption cycles in Longtan period. The results indicate that REE patterns are not controlled by materials from the seawater or land plants. The predominant sources of REEs are from terrigenous material as indicated by negative Eu anomaly. So, the sources of REEs are controlled by terrigenous material, and the Mount Emei basalt is the predominant source of terrigenous material. Thus, transgression-regression is another control factor of REEs enrichment. 展开更多
关键词 rare earth elements rees) control factors material sources transgression-regression Mount Emei basalt LatePermian
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Breakthrough in the China's Separation Technology for Extraction of Rare Earth Elements
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作者 HAO Ziguo FEI Hongcai +1 位作者 LIU Lian Susan TURNER 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2013年第6期1743-1744,共2页
Separation technology of rare earth elements (REEs), as the critical step in the separation process, had long been fraught with technical difficulty. A research project conducted by Baotou Shibo Rare Earth Extracti... Separation technology of rare earth elements (REEs), as the critical step in the separation process, had long been fraught with technical difficulty. A research project conducted by Baotou Shibo Rare Earth Extraction & Equipment Co. Ltd., Baotou REE Research Institute, and Baotou Steel & REE Group Hi-Tech Co. Ltd (Inner Mongolia), has successfully solved the problem using a centrifugal extractor and advanced techniques to achieve a key breakthrough. 展开更多
关键词 LINE Breakthrough in the China’s Separation Technology for Extraction of rare earth elements ree
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The World Production and Trade of Rare Earth Elements: The Position of the Pacific Area
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作者 Carlos Encinas-Ferrer Francisco Javier ValderreY-Villar +1 位作者 Clemente Hernandez-Rodriguez Antonio Uson-Sardana 《Chinese Business Review》 2014年第4期209-220,共12页
In this paper we analyze the characteristics of the so-called rare earth elements (REEs) and its industrial applications. We present the policy, or lack thereof, in the countries in the Pacific Rim for its mining an... In this paper we analyze the characteristics of the so-called rare earth elements (REEs) and its industrial applications. We present the policy, or lack thereof, in the countries in the Pacific Rim for its mining and commerce, and the current and future weight that rare earth minerals will have in international trade. The technological revolution experienced over the last 25 years, has brought the REEs to the public's attention for being instrumental in obtaining catalysts, lasers and optical fiber, luminescent substances and LEDs, superconductors, permanent magnets, batteries and ultra-capacitors. China's leading position as the supplier of these minerals worldwide, and its recent export restriction policy for domestic industrial activities have driven up international prices. Price increase for REEs is leading to the need for both recycling and its replacement. It has also led other countries in the Asia Pacific Rim to prospect new potential sites on their own territories, or even to restart operations in deposits that had been previously abandoned. Those strategies will likely gain greater importance as environmental pollution problems associated with the exploitation, processing, and recovery of REEs increase. 展开更多
关键词 rare earth metals or elements China rees production TRADE public policies PROSPECTING technologicalrevolution
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THE Nb-Ta AND RARE EARTH ELEMENT DEPOSITS OF GRANITE TYPE IN SOUTHEASTERN CHINA
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《Geotectonica et Metallogenia》 1994年第Z2期57-58,共2页
关键词 ree TA THE Nb-Ta AND rare earth element DEPOSITS OF GRANITE TYPE IN SOUTHEASTERN CHINA
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REE and Trace Element Geochemistry of Yinachang Fe-Cu-REE Deposit, Yunnan Province, China 被引量:4
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作者 杨耀民 涂光炽 胡瑞忠 《Chinese Journal Of Geochemistry》 EI CAS 2004年第3期265-274,共10页
REE and other trace elements in ores, wall rocks, alkaline volcanic rocks and diabase dikes have been determined in the Yinachang Fe-Cu-REE deposit. Comparative studies of REE and trace element geochemical characteris... REE and other trace elements in ores, wall rocks, alkaline volcanic rocks and diabase dikes have been determined in the Yinachang Fe-Cu-REE deposit. Comparative studies of REE and trace element geochemical characteristics of these geological bodies indicate that the ores and alkaline volcanic rocks contain abundant REE and Y ({65.9}-{4633})×10+{-6}, with higher abundances of As, Mo, Nb, Co and U than those of the crust. Their chondrite-normalized patterns show a strong enrichment of LREE and a positive Eu anomaly, in contrast to those of the dolomites which are characterized by slight LREE enrichment and moderate negative Eu anomaly. The REE patterns of ores are similar to those of hydrothermal sediment cores in the East Pacific Rise, whereas the REE patterns of dolomites are similar to those of PAAS (Post-Archean Average Shale). In combination with the geological setting of the deposit, the primary ore-forming fluids might have higher REE and volatile elements, and might have been derived from mantle degassing, or the alkaline volcanic magmas. The Yinachang Fe-Cu-REE ore deposit is considered to be of volcanic exhalation-hydrothermal sedimentary origin. 展开更多
关键词 稀土元素氧化物 蒸发水疗法 铕异常 Lree 地球化学 丰度
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Direct microwave leaching conditions of rare earth elements in fluorescent wastes
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作者 A.Bilen B.Birol +2 位作者 M.N.Saridede S.S.Kaplan M.S.Sonmez 《Journal of Rare Earths》 SCIE EI CAS CSCD 2024年第6期1165-1174,I0007,共11页
The luminescent phosphor powder in the fluorescent lamp constitutes 2%of the lamp’s weight.It can be mentioned that fluorescent wastes are a crucial raw material to produce rare earth oxides.In the present study,micr... The luminescent phosphor powder in the fluorescent lamp constitutes 2%of the lamp’s weight.It can be mentioned that fluorescent wastes are a crucial raw material to produce rare earth oxides.In the present study,microwave leaching process was conducted to dissolve rare earth elements yttrium(Y),europium(Eu),and remaining rare earth elements(REEs)present in the phosphor powder of the fluorescent lamp.and the yields were compared.In the microwave leaching process,the effects of the temperature(80-160℃),acid type(hydrochloric acid(HCl),nitric acid(HNO_(3)),sulphuric acid(H_(2)SO_(4))),acid concentration(0.5-6 mol/L),solid to liquid ratio(0.1:10-0.5:10)and reaction time(5-90 min)parameters on leaching efficiencies of varying rare earth elements and calcium were investigated.The highest yield was obtained in the direct microwave leaching of fluorescent waste with the experimental conditions of 6 mol/L HCl,160℃,0.1:10 solid-to-liquid ratio(S:L),and 90 min.Activation energy calculations were made,and kinetic models of the reactions were obtained,and it is observed that Y and Eu dissolution is diffusion-controlled,on the other hand,lanthanum(La),cerium(Ce),and terbium(Tb)were examined to be chemical reaction controlled.Moreover,calcium(Ca)and gadolinium(Gd)seem coherent with the mixed model.Concurrently,mathematical models of all experimental studies are created with the response surface Box-Behnken method and the correlation coefficients of all the models are over 90%. 展开更多
关键词 rare earth elements(rees) Direct microwave leaching Fluorescent waste Kinetic models Response surface method
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土壤侵蚀REE示踪法研究初报 被引量:61
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作者 田均良 周佩华 +4 位作者 刘普灵 吴普特 郑世清 李雅琦 武春龙 《水土保持学报》 CSCD 北大核心 1992年第4期23-27,共5页
文中提出了一种研究土壤侵蚀的新方法——稀土元素(REE)示踪法;讨论了该方法的基本原理、REE施加量计算、实验技术及应用前景。人工降雨小区的试验结果表明,该方法不但可用于精确测定不同地形部位侵蚀量,其测定结果相对误差小于15%,并... 文中提出了一种研究土壤侵蚀的新方法——稀土元素(REE)示踪法;讨论了该方法的基本原理、REE施加量计算、实验技术及应用前景。人工降雨小区的试验结果表明,该方法不但可用于精确测定不同地形部位侵蚀量,其测定结果相对误差小于15%,并可揭示降雨侵蚀过程不同地形部位侵蚀量的变化趋势。 展开更多
关键词 稀土元素 示踪法 土壤侵蚀 ree
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湖南安化留茶坡硅质岩的REE地球化学特征及其意义 被引量:28
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作者 常华进 储雪蕾 +2 位作者 冯连君 黄晶 张启锐 《中国地质》 CAS CSCD 2008年第5期879-887,共9页
湖南安化留茶坡硅质岩沉积在埃迪卡拉纪末期(551~542Ma)的深水盆地中,它们具有如下REE地球化学特征:和PAAS相比,∑REE含量很低(8.6×10-6~18×10-6,平均13.6×10-6),Y/Ho比值较高(33.6~43.9,平均37.4),接近现代海水的Y/H... 湖南安化留茶坡硅质岩沉积在埃迪卡拉纪末期(551~542Ma)的深水盆地中,它们具有如下REE地球化学特征:和PAAS相比,∑REE含量很低(8.6×10-6~18×10-6,平均13.6×10-6),Y/Ho比值较高(33.6~43.9,平均37.4),接近现代海水的Y/Ho比值(44);正的La异常(LaN/CeN平均为1.46),中等负的Ce异常(平均0.65),弱的正Eu异常(平均1.1),正的Gd异常(平均1.07),正的Y异常(平均1.22),LREE和MREE相对于HREE亏损(LaN/YbN平均为0.17,GdN/YbN平均为0.45),显示出和现代海水相似的REE特征,而与海底热液流体及与热液有关的碧玉的REE特征明显不同。这些表明留茶坡硅质岩受陆源碎屑及热液流体的影响很小。留茶坡硅质岩是由风化作用大量带入海洋的溶解的硅质化学沉积而成的。生物作用促进了海水中溶解硅质的沉淀。 展开更多
关键词 硅质岩 海水 热液 ree 埃迪卡拉纪 留茶坡组 湖南
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