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1.
Eleven rare earth elements (REE) have been determined in ten USGS and two CCRMP igneous rock standards using high performance ion chromatography. Duplicate analyses of two or more separately prepared aliquots of each sample were undertaken; reproducibility was better than 5% for each of the REE. In most cases, the results compare closely with published REE values for those samples for which the REE are well characterised. Where the results for individual elements are in disagreement with published data, the more erratic patterns yielded by the earlier data when plotted on chondrite-normalised REE diagrams suggest that values determined in this study are of greater accuracy. 相似文献
2.
DETERMINATION OF RARE EARTH ELEMENTS IN SIXTEEN SILICATE REFERENCE SAMPLES BY ICP-MS AFTER TM ADDITION AND ION EXCHANGE SEPARATION 总被引：7，自引：0，他引：7
J.A. BARRAT F. KELLER J. AMOSSÉ R.N. TAYLOR R.W. NESBITT T. HIRATA 《Geostandards and Geoanalytical Research》1996,20(1):133-139
This study reports the results of thirteen rare earth elements (REE) in sixteen geochemical reference samples. The analytical procedure involved dissolution of a whole rock or mineral separate, spiking with Tm, and separation of the REE using a simple ion-exchange chromatography procedure. The resulting REE solutions were analysed by ICP-MS. The results are compared with literature values. The agreement between our data and recommended or ID-TIMS values is very favorable. The precision of the technique is better than 5% (2) for all the REE. 相似文献
3.
The effects of terrestrial weathering on REE mobilization are evaluated for a variety of uncommon meteorites found in Antarctica and in hot deserts. The meteorites analyzed include 7 non-cumulate eucrites, 10 shergottites, 3 nakhlites, 2 lunar meteorites, 4 angrites, 10 acapulcoites, 1 winonaite, and 1 brachinite. In-situ concentration measurements of lanthanides and selected other minor and trace elements were made on individual grains by secondary ion mass spectrometry (SIMS). In Antarctic meteorites, oxidation converts Ce3+ to Ce4+, which is less soluble than the trivalent REE, resulting in Ce anomalies. The mineral most affected is low-Ca pyroxene. However, not all grains of a given mineral are, and distinct analyses of a single grain can even yield REE patterns with and without Ce anomalies. The effect is most pronounced for Antarctic eucrites in which Ce anomalies are observed not only in individual minerals but also in whole rock samples. Although Ce anomalies are observed in meteorites from hot deserts as well, the most characteristic signs of chemical alteration in this environment are a LREE enrichment with a typical crustal signature, as well as Sr, Ba and U contaminations. These can modify the whole rock REE patterns and disturb the isotope systematics used to date these objects. The LREE contamination is highly heterogeneous, affecting some grains and not others of a given mineral (mainly olivine and low-Ca pyroxene, the two minerals with the lowest REE concentrations). The major conduit for REE movement is through shock-induced cracks and defects, and the highest levels of contamination are found in altered material filling such veins and cracks. Meteorites that experienced low shock levels and those that are highly recrystallized are the least altered. 相似文献
4.
安徽省皖南地区岩浆岩分布广泛,地貌、气候条件适宜,有利于花岗岩风化壳的形成、保存,且基岩的稀土丰度较高,有利于离子吸附型稀土矿床的形成。通过在皖南地区的工作,分析了离子吸附型稀土矿床的内生成矿条件(基岩中稀土丰度、稀土元素赋存状态、矿物组合及岩石结构、构造),表生成矿条件(气候条件、风化壳发育程度、地貌特征),总结了离子吸附型稀土矿床的成矿特征、找矿标志。 相似文献
5.
Summary Melt inclusions in olivine and apatite, and REE distribution of apatite were studied in one of the least differentiated members
of the oldest alkaline succession of Mt. Etna. Apatite occurs both as microphenocrysts and as inclusions in olivine crystals,
even in the most Mg-rich ones (Fo82). In addition phenocrysts and groundmass are composed of plagioclase, clinopyroxene, olivine and magnetite.
Apatite is fluor-apatite, with rather homogeneous major element (measured by electron microprobe, EMP) and REE (measured by
laser-ablation microprobe, LAM, and by secondary ion mass spectrometer, SIMS) contents. REE are enriched when compared to
the whole rock, with contents in olivine-hosted apatite lower than or the same as those of the microphenocryst cores; these
in turn show lower REE values than their edges. Distribution coefficients, calculated from LAM data of microphenocryst edges
and whole rock analyses, are higher for LREE (8–12) than for HREE (5–4).
In the SiO2 vs. P2O5 diagram melt inclusions and whole rock samples define a trend that is consistent with continuous apatite extraction from
a “high P” basalt magma. Finally, whole rock data show LREE/HREE (La/Lu)n enrichment ratios from hawaiites to mugearites (=1.14), consistent with apatite fractionation, lower than those documented
for lavas of the “low P” type (enrichment ratio = 1.34–1.37), where conditions for apatite saturation were not established.
Received January 2, 2000; revised version accepted April 2, 2001 相似文献
6.
Yu Liu Qiu‐Li Li Guo‐Qiang Tang Xian‐Hua Li 《Geostandards and Geoanalytical Research》2020,44(3):421-437
A combined geochronological and geochemical investigation for the same domain of zircon provides valuable information on timing and genesis, particularly in the case of multi‐growth metamorphic zircon. A high spatial resolution concurrent analytical method for zircon U‐Pb age and rare earth element content was successfully achieved in this study, using a multi‐collector secondary ion mass spectrometer (SIMS) at a ~ 8 μm diameter scale. Special instrument parameters were employed, including a high mass resolution of approximately 15000 applied to replace the previous energy filter method, and a dynamic multi‐collector mode used to reduce the measurement time to 18 min per analysis. Six zircon reference materials yielded precise and accurate 206Pb/238U ages, which are comparable to those obtained by the ordinary mono‐collector method, but with 2–3 times higher spatial resolution. All zircon grains measured in this study showed enriched heavy‐REE (HREE) contents consistent with previously reported values determined by LA and solution ICP‐MS methods. The light‐REE (LREE) mass fractions measured using both SIMS and LA‐ICP‐MS methods in this study, although with quite different volume, show consistent results within uncertainties. 相似文献
7.
为研究兴蒙造山带-华北克拉通地球化学走廊带区域地球化学组成及其横向空间变化,统计分析不同地理单元和五万图幅单元的REE含量并绘制其空间分布折线图.内蒙古半干旱草原土壤中稀土含量较低,与其草原沙土的粘土矿物较少有关;江苏北部冲积平原区的土壤中稀土含量较高,与降雨量存在良好空间对应关系.内蒙古红格尔到河北张家口,土壤与岩石∑REE的比值绝大多数小于1,REE发生贫化;山东章丘到江苏连云港,比值基本大于1,REE发生富集.华北克拉通内蒙地块土壤稀土特征与兴蒙造山带相似,可能受其草原沙土景观的影响.在不同构造单元之间,LREE与HREE亏损与富集的空间分布存在细微差异.结果表明:地理景观,特别是黏土矿物是影响土壤REE含量的重要因素,降雨量与REE存在良好空间对应关系,REE自身的地球化学性质的差异在土壤形成过程中对轻重稀土元素分异具有重要影响. 相似文献
8.
9.
朝鲜半岛北部定州与铁山稀土矿相关碱性岩和花岗岩的岩石学和SIMS锆石U-Pb年代学特征研究 总被引：2，自引：2，他引：0
朝鲜半岛北侧的狼林地块是中朝克拉通的重要组成部分,狼林地块具有与辽南地块以及辽吉活动带类似的早前寒武纪岩石组成、变质和变形特征。我们在分布有稀土矿的朝鲜定州-铁山一带(狼林地块西北部),采集了与稀土矿密切相关的碱性岩(粗粒正长岩和萤石化霓辉正长岩)和花岗岩(似斑状花岗岩)样品。岩石样品的岩相学观察表明,定州与铁山地区的碱性岩和花岗岩并不显示明显的岩浆期之后的热液蚀变特征。SIMS锆石U-Pb定年结果显示粗粒正长岩的岩浆结晶年龄为1865±6Ma,萤石化霓辉正长岩的岩浆结晶年龄为1868±8Ma,铁山地区的四件似斑状花岗岩的年龄结果分别为1871±13 Ma、1866±8 Ma、1872±6 Ma和1873±7 Ma,这些年龄值一方面代表了岩浆活动时代,另一方面可能也代表了朝鲜定州和铁山稀土矿的成矿时代。狼林地块的这些碱性岩与花岗岩的时代与华北克拉通辽吉活动带以及狼林地块其它地区的高级变质作用同期,并且在辽南地块,也有类似碱性岩的报道。综合现有的证据表明,辽吉活动带、辽南地块以及狼林地块在古元古代可能属于同一个大型构造带,并且这个构造带(或者构造带的一部分)当时处于伸展的构造背景。通过全面对比野外观测结果、岩石的岩相结构、岩浆结晶时代可知,朝鲜定州和铁山一带的稀土矿与中朝克拉通的世界级稀土矿——白云鄂博,在岩石组合、稀土矿物组成、岩石蚀变特征、成矿时代等方面存在较大的区别。关于这一稀土矿的具体稀土矿物组成、矿床成因以及储量等众多问题,未来还需要进行大量的工作。 相似文献
10.
Hisayoshi YURIMOTO Isao SAKAGUCHI Norimasa NISHIDA Shigeho SUENO 《Geostandards and Geoanalytical Research》1991,15(1):155-159
Trace level determination of nickel in silicate rock samples has been achieved using secondary ion mass spectrometry (SIMS) with kinetic energy filtering. Standard rock references, issued by the Geological Survey of Japan, were fused into glass and used as standards for the SIMS analysis. Due to interferences from the glass matrix, the secondary ion of mass 60 was only useful for Ni, although the secondary ion was interfered mainly by CaO+. The contributions of these molecular ions were deconvolved by a least squares regression. Good linear correlation between results after the deconvolution and the Ni concentration in the glass standards was obtained. The uncertainties of the SIMS analysis depend strongly on the degree of contribution of CaO+ molecular ion. Such a method of SIMS analysis is especially useful to study the detailed behavior of Ni on a micro-scale in Ca-poor materials. 相似文献
11.
Chromite ores formation is still a debated topic and, in this study, detailed analyses of major, minor elements by EMPA and Rare Earth Elements (REE) by SIMS, were performed on silicate inclusions detected in chromite grains of chromitite pods, enveloping dunites and on clinopyroxene of lherzolitic host rock of well known Trodoos chromite ores. Results show the complexity of relationships among lithologies that reflects the subtlety of genetic events and of chromite ore occurrence.Analyses of textural and chemical features have led to a better understanding of the chromite ore genetic process, that is related to a supra-subduction geodynamic setting where partial melting processes were overlapped by metasomatic events.Metasomatism, that marks the general genetic context, is characterized by the presence of a hydrated boninitic melt that favors the precipitation of chromite ores. Chromite ores, typical of ophiolite complexes and usually enveloped by dunite are, in this case, characterized by the presence of two different types of dunites whose geochemical differences are reflected by olivine mineral chemistry and by different REE patterns of analyzed clinopyroxenes. Such geochemical marks, related to different magmatic and metasomatic events, could be a main key for location of fertile or barren dunites in terms of chromite ore occurrence in the field. 相似文献
12.
Joseph L. HARRIS Louis J. SCHWARZ William M. D'ANGELO Francis J. FLANAGAN 《Geostandards and Geoanalytical Research》1981,5(2):125-128
Additional data for gabbro, GOG-1, were determined by instrumental-neutron-activation analysis, atomic-absorption spectrometry, and semi-quantitative spectrographic analysis. F ratios calculated in the analysis of variance for 26 sets of data for elements determined by the three methods were not significant, and hence the elements are distributed homogeneously among the bottles. The agreement between our data and the averages previously published ranges from very good to poor. More analytical data are necessary to establish reliable estimates of the concentrations of elements in GOG-1 and in two other gabbros so that three gabbros may be available to geochemists for use as standards. 相似文献
13.
Akira Imai Kotaro Yonezu Kenzo Sanematsu Takashi Ikuno Shingo Ishida Koichiro Watanabe Visut Pisutha‐Arnond Somchai Nakapadungrat Jarupong Boosayasak 《Resource Geology》2013,63(1):84-98
Geochemical studies were conducted on the hydrothermally altered granitic rocks in the Ranong and Takua Pa tin‐fields in southern Thailand in order to investigate the mode of occurrence of REE (rare earth elements), with emphasis placed on a potential REE resource associated with granitic rocks in the Southeast Asian Tin Belt. The total REE (ΣREE) content of altered granitic rocks ranges from 130 to 350 ppm at Haad Son Paen (which is presently mined for kaolin clay) in the Ranong tin‐field, and that of altered granitic rocks and kaolinite veinlets reaches up to 424 ppm and 872 ppm, respectively, at Nok Hook in the Takua Pa tin‐field. Rare earth elements in the altered granitic rocks and kaolinite veinlets show a relatively flat chondrite‐normalized pattern, thus enriched in heavy REE compared with the original granitic rocks and their weathered crusts. At Nok Hook (Takua Pa), the ΣREE content of kaolinite separated from an altered granitic rock by elutriation is 1313 ppm, a ΣREE amount about four times higher than that of whole‐rock composition of the altered granitic rock. Chondrite‐normalized REE patterns of the elutriated kaolinite and of the altered granite are relatively flat. Sequential extraction experiments suggest that 41 and 85 percent of REE are present as ion exchangeable‐form in the altered granitic rock, and in the kaolinite veinlets, respectively. In addition, more than 90% of REE in the kaolinite veinlets are present as the acid‐soluble state. On the other hand, the ΣREE content of kaolinite veinlets and of the kaolinite concentrated by elutriation from an altered granitic rock at Haad Som Paen (Ranong) is 70 ppm and 75 ppm, respectively, thus enrichment of REE in kaolinite was not confirmed. In addition, by the sequential extraction experiments, 23% and 4% of REE were extracted from the altered granitic rock and the kaolinite veinlets at Haad Som Paen. In the altered granitic rocks at Haad Som Paen, REE are present as refractory phases, and REE in the acid‐soluble states had been leached by hydrothermal fluid. 相似文献
14.
对鄂尔多斯盆地中东部奧陶系马家沟组风化壳岩溶储层的碳酸盐岩、硫酸盐岩和碎屑岩类岩石样品以及上覆层本溪组碎屑岩样品所作的稀土元素含量与配分特征分析表明,稀土元素分馏特征与富集特征明显,非可溶岩的稀土元素总含量与富集程度高于可溶岩。轻、重稀土元素关系分析表明,可溶岩的轻稀土元素迁移大于重稀土元素的分馏效应,揭示了可溶岩经历了不同的岩溶环境,马家沟组碎屑岩中的稀土元素与上覆层本溪组底部砂泥岩中的稀土元素是同源的。δEu与δCe分析表明,δEu的活化迁移,反映了表生期岩溶环境的存在,而δCe的相对富集,揭示了埋藏期岩溶的发育及其与天然气生成运聚的密切关系。 相似文献
15.
赣南新元古代变质岩稀土矿物及其地球化学特征 总被引：3，自引：2，他引：1
近年来赣南地区首次报道了变质岩离子吸附型稀土矿床的发现,为离子吸附型稀土的找矿提供了新思路。赣南地区新元古代变质岩大面积分布,风化壳也广泛发育。文章对30件稀土元素含量(300×10~(-6))高的变质岩矿物样品进行了详细的电子探针分析,旨在查明赣南新元古代不同类型变质岩中的稀土矿物种类及特征,探讨其成因、对全岩稀土元素含量的贡献以及离子吸附型稀土元素的成矿潜力。研究表明,区域上变质岩可大致分为6类,分别是变质凝灰岩类、板岩类、千枚岩类、片岩类、变砂岩类和变粒岩类,不同类型变质岩的稀土矿物组合不同,除了普遍存在的、难风化的独居石、磷钇矿和锆石外,部分岩性中出现易风化的褐帘石、含稀土元素绿泥石和含稀土元素金红石,及表生的水磷酸盐和磷铝酸盐等矿物。这些富稀土矿物贡献了全岩中大部分稀土元素,且部分矿物成因与后期流体作用相关,为成矿提供了良好的条件。文章总结分析认为,赣南地区广泛分布的变质岩中,片岩类、变砂岩类和变质凝灰岩类均具有相对易风化的稀土矿物组合,尤其变质凝灰岩类和变砂岩类,能为离子吸附型稀土成矿提供充足的物质来源,具有可观的离子吸附型稀土成矿潜力。 相似文献
16.
对黑龙江省８４个砂金样品及７个岩金样品，用等离子质谱仪分析了它们的稀土元素含量，岩金以稀土总量低，轻重稀土分离程度小为特征，不同类型岩金矿床的自然金，其稀土配分曲线有明显差异，砂金样品则以较富集轻稀土为特征，稀土元素含量继承了岩金的部分特点，自然金稀土元素的赋存状态为Ｕ，Ｔｈ矿物的微细包体，其分配特点可用来讨论岩金矿床的分类以及砂金的原生来源。 相似文献
17.
18.
Rare earth elements were determined by secondary ion mass spectrometry (SIMS) for 12 igneous rocks and one feldspar separate from the new rock reference samples of the Geological Survey of Japan. The study presents an expanded application of the SIMS facility. 相似文献
19.
Yasuhiro Kato 《Resource Geology》1999,49(4):183-198
Abstract: Systematic data of rare earth elements (REEs) are presented in order to put some constraints on the origin of hydrothermal fluids responsible for two contrastive skarn deposits in Japan; the Kamioka Zn-Pb and Yoshiwara-Sannotake Cu(-Fe) deposits. Carbon and oxygen isotopic studies have demonstrated that the hydrothermal fluids responsible for the Kamioka Zn-Pb deposits are of meteoric water origin whereas those for the Yoshiwara-Sannotake Cu(-Fe) deposits are of magmatic water origin. The REE abundances of epidote skarn derived from aluminous rocks, garnet and clinopyroxene in calcic exoskarn derived from limestone, and interstitial calcite associated with sulfide minerals were determined for these contrastive skarn deposits by inductively-coupled plasma mass spectrometry (ICP-MS). A significant difference in the REE concentrations is not found between epidote skarn and aluminous original rock (plagioclase-clinopyroxene rock, called Inishi rock) from the Kamioka Zn-Pb deposits, indicating that the REEs are generally immobile during the formation of epidote skarn, and that the REE concentrations of the hydrothermal fluid are considerably low relative to the aluminous original rock. In contrast, the epidote skarn exhibits enrichment of Eu with increasing total REE concentrations relative to the aluminous original rock (quartz diorite) in the Yoshiwara-Sannotake Cu(-Fe) deposits, implying a contribution of magmatic fluid derived from granitoids during the skarn formation. Limestone generally has much lower REE concentrations related to surrounding aluminous rocks, and thus the REE concentrations of garnet and clinopyroxene in calcic exoskarn, originated from limestone, are variable due to the interaction with the hydrothermal fluids. The chondrite-normalized REE patterns of garnet, clinopyroxene, and interstitial calcite exactly provide useful information on origins of hydrothermal fluids. The REE patterns of these minerals from the Kamioka Zn-Pb deposits show lower (Pr/Yb)cn ratios, and negative Ce and Eu anomalies inherited from limestone with the decrease of This suggests that the hydrothermal fluids responsible for the Kamioka Zn-Pb deposits were depleted in REEs, and were not magmatic water in origin, but presumably meteoric one. In striking contrast, the REE patterns of exoskarn minerals and calcite from the Yoshiwara-Sannotake Cu(-Fe) deposits exhibit a positive Eu anomaly, and high (Pr/Yb)cn ratios with the considerable increase of σREE and the disappearance of negative Ce anomaly, implying that the fluids were dominantly of magmatic origin. The REE indices are very likely to be an excellent indicator to origins of the skarn deposits. 相似文献
20.
REE示踪沉积物物源研究进展 总被引：101，自引：0，他引：101
ＲＥＥ作为一种重要的沉积物物源示踪剂运用很广。在介绍了ＲＥＥ性质的基础上，对海水、河水、沉积岩、河流及边缘海沉积物中的ＲＥＥ元素丰度与配分模式特征进行了深入综述，概述了影响和控制ＲＥＥ丰度、模式及分馏特征的主要因素；论述了ＲＥＥ的物泊示踪意义以及在国内外应用情况与存在问题：源岩风化对ＲＥＥ分馏的影响；颗粒运及沉积时水动力分选对ＲＥＥ分馏可能造成的影响，即不同粒级中的ＲＥＥ不同的丰度与配分模式和碎屑 相似文献