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为了研究河南省卢氏县官坡—五里川锑成矿带成矿机制,对其稀土元素地球化学特征进行分析。锑矿带内锑矿石及其他类型岩石轻、重稀土元素比值较高,且都呈现为Eu负异常,稀土元素配分模式总体上表现为轻稀土富集型。锑矿带内各种类型岩(矿)石中稀土总量分布表现出一定规律性,大理岩、锑矿石中稀土元素总量较高,构造带岩石及附近围岩的稀土元素总量偏低,说明锑矿带的锑及成矿热液主要来自于下地壳和上地幔,热液上升过程中锑矿床经历了多阶段的分馏、交代作用,导致稀土元素从围岩中大量迁出,并富集于锑矿床内。 相似文献
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赣南上窖铀矿床萤石稀土元素地球化学特征及其源区意义 总被引:1,自引:0,他引:1
上窖铀矿床是南岭多金属成矿带黄沙铀矿区的重要组成部分。萤石是该矿床最主要的脉石矿物之一,其形成与铀矿化密切相关。本文在详细的野外和室内岩相学观察基础上,系统的研究了该矿床中萤石的稀土元素(含部分微量元素)地球化学特征。结果表明,主成矿期紫黑色萤石的稀土元素总量变化于59.47×10~(-6)~68.97×10~(-6)之间,其球粒陨石标准化配分模式总体为轻稀土富集"右倾"型;成矿晚期浅绿色萤石的稀土元素总量变化于41.87×10~(-6)~43.12×10~(-6)之间,配分模式整体呈现"M型"四分组效应;两者均具有弱正铈异常(δCe=1.12~1.23)和较强的负铕异常(δEu=0.63~0.65)特征。明显区别于赣南-粤北地区前寒武纪基底岩石的稀土元素配分特征,而与矿区围岩、矿石的稀土元素配分模式相类似。此外,相对于矿区围岩、中国东部地壳和赣南-粤北地区前寒武纪基底岩石,紫黑色萤石中U含量明显富集,Th、Ba含量亏损。综合矿区成矿地质背景及上述元素地球化学特征认为,上窖铀矿床成矿流体源自前寒武纪基底岩石或与其进行了较为充分的水-岩相互作用的可能性较小,成矿流体以地幔流体为主,伴有部分经历了深部循环的大气水,相对于前寒武纪基底岩石而言,为一经历了深部循环的外来还原性流体。 相似文献
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贵州下寒武统黑色页岩稀土元素地球化学特征 总被引:3,自引:1,他引:2
研究了贵州开阳、织金等地碳质页岩系岩石化学特征及稀土元素特征.样品中K2O含量大于Na2O,与我国南方类型岩石K2O>Na2O特征相一致.黑色页岩的稀土元素地球化学特征表明,贵州开阳、织金等地区下寒武统牛蹄塘组黑色岩系中稀土元素总量ΣREE为227.47×10-6~623.18×10-6,黑色页岩系稀土均值为532.69×10-6,其稀土总量偏高.黑色页岩系Y含量范围在122.02×10-6~188.40×10-6,均值为155.26×10-6,反映了富集钇的基本特征.黑色页岩中Dy元素发生一定程度富集.LREE/HREE比值为1.35~1.67,表明黑色页岩系稀土含量组成属于轻重稀土相对集中型.与织金磷块岩稀土组成类似,反映了稀土元素形成具有一定渊源性.稀土组成模式及稀土元素配分模式图表明是较典型的海相沉积物稀土配分模式.综合分析得出本区黑色页岩系属正常海相沉积成因. 相似文献
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滇—黔—桂地区是我国重要的金成矿区之一,分布有众多高温岩浆热液型金(铜)矿床和低温热液型金矿床,但这些矿床的成矿物质来源和形成过程仍存在争议。通过对高温岩浆—热液型金(铜)矿床(姚安金矿床和普朗金铜矿床)和低温卡林型金矿床(八渡和泥堡)中的热液磷灰石进行微量元素统计分析发现:高温富碱斑岩型金(铜)矿床中的磷灰石自形程度较好,具有较高的F和Cl含量,稀土元素呈轻稀土富集,重稀土亏损;相对而言,低温卡林型金矿床中产出的磷灰石自形程度较差,具有相对较低的F和Cl含量,稀土呈中稀土富集模式。另外,磷灰石δEu-δCe图解和球粒陨石标准化稀土元素配分模式揭示卡林型金矿床相对于岩浆热液型铜、金矿床具有更高的氧逸度。结合右江盆地辉锑矿稀土元素地球化学分析,认为磷灰石(包括萤石和方解石)中稀土(MREE)富集特征指示低温成矿流体可能与特殊的盆地基底岩石存在一定联系。综合分析认为:磷灰石在高温—中低温金矿床中具有独特的地球化学特征,能够有效揭示矿床类型及成矿流体演化过程。 相似文献
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甘肃枣子沟金矿床稀土元素地球化学特征 总被引:1,自引:0,他引:1
对比研究了枣子沟金矿区内不同类型矿石与成矿有关的岩浆岩及地层的稀土元素地球化学特征,借以示踪成矿物质来源。研究表明,矿床不同类型矿石的稀土元素配分曲线既有相似又有差别,反映成矿物质具有多样性;矿石与容矿岩石(地层、岩浆岩)稀土元素配分曲线颇为相似,总体呈右倾型,具Eu负异常。表明成矿与容矿岩石(地层、岩浆岩)具有一定的成因联系。成矿物质来源于壳源及壳幔混合。地幔流体可能参与了矿床成矿作用。成矿环境表现为早期还原,晚期由还原向氧化转化。 相似文献
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以《湖南省越城岭地区稀有稀散金属矿产调查评价》项目为依托,通过数据对比、图解分析等方法,对该区500余件岩石、土壤样进行统计,分析了不同岩相带、土壤垂直分带中稀土元素含量特征及配分模式,讨论了稀土元素对越城岭岩体成因的指示意义。研究结果表明,越城岭岩体各岩相带内稀土元素含量具有明显的差异性,且分带性明显;土壤中稀土相对岩石更富集;该区稀土元素曲线配分右倾;轻稀土相对重稀土较富集;普遍具Eu中等负异常;稀土元素特征指示该岩体具有重熔型花岗岩的特征。 相似文献
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In order to get a better understanding of metallogeny, the geochemical characteristics of REE and trace element for Gejiu tin polymetallic deposits were studied by comparing concentrations of REE and trace elements in different type ores and rocks, including skarn-type ore, bedded-type ore, vein-type ore, altered granite, country rocks. Results of this study indicated that the metallogenic matters for different type ores in the study area might be derived from the same origin source, which may be mainly related to granitic activities. Furthermore, there are some differences in concentrations of REE in different ores due to their different depositiona! mechanism during that time. LREE concentrations were enriched relatively in the vein-type ores and the bedded-type ores with relatively low total REE concentrations, whereas total REE concentrations were higher in the skarn-type ores with LREE and HREE concentrations in wide variation ranges. 相似文献
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Geochemistry of Rare Earth Elements in Xikeng Ag-Pb-Zn Ore Deposit, South Anhui, China 总被引:2,自引:0,他引:2
TheSouthAnhuiislocatedinthelowerYangtzeRiverplatformalfoldbeltoftheYangtzeparaplatforminJiangnan .Alarge scaletransgressionsincethelateSinianafterearlySinianNantuoglacialperiodledablackshaleformationconsistingofblackcarbona ceousshale ,carbonaceousmudst… 相似文献
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宝兴沟金矿床是位于上黑龙江成矿带上的大型岩金矿床。在充分收集矿区已有资料的基础上,结合矿区钻孔样品及地球化学剖面数据,对矿床地球化学特征进行了研究。研究表明,二十二站组地层成矿元素含量普遍高于克拉克值,且元素变异系数较大,有利于发生迁移,矿体两侧围岩中存在成矿元素向矿体迁移而产生的低值区。地层、构造、岩浆岩是主要的控矿因素,二十二站组地层为矿源层,北东向断裂及其次级断裂控制了矿体的形态和产状,(石英)闪长岩脉、闪长玢岩脉与成矿关系密切,二十二站组地层、北东向构造及岩脉同时存在是寻找金矿体的理想部位。 相似文献
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中条山胡家峪铜矿区含矿岩系的地球化学特征及其地质意义 总被引:1,自引:0,他引:1
胡家峪铜矿床大地构造位置处于华北克拉通中部造山带南缘的中条山地区,矿床主要赋存于古元古界中条群篦子沟组含碳片岩、不纯大理岩和硅质钠长岩等岩石中,次为余家山组白云石大理岩中。对矿区内的含矿岩系进行了全岩地球化学测试分析,主量元素特征表明矿区内的含矿岩系均表现出富镁、富铝的特征;微量元素特征显示,所有样品均呈现出Nb、Ta、Ti负异常的现象,显示出与俯冲带岩浆地球化学类似的特征;稀土元素特征显示出一定程度的轻重稀土分馏,轻稀土富集,所有样品都表现出不同程度的铕负异常,表明这些含矿岩系形成于还原沉积环境中。研究认为,胡家峪铜矿床的成矿构造背景为俯冲后形成的弧后盆地;容矿岩石与国内典型热水喷流矿床相比,在地球化学特征方面有一定相似之处。因此,胡家峪铜矿床应为热水喷流沉积矿床。 相似文献
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通过对青海省都兰县各玛龙铅锌矿区地质、地球化学特征进行归纳、总结,研究并分析了矿床地质特征和地球化学异常特征,概述了矿区地层、断裂体系和岩浆岩的分布情况,预测深部成矿的可能性,为后期找矿勘探提供建议和指导。随着找矿难度的不断加大,地球化学找矿方法在地质工作中的地位显得越来越重要,在地质工作中的应用也越来越广泛。各玛龙铅锌矿的发现是地球化学找矿方法的又一成功实例,通过对该矿区的地质地球化学特征进行研究和总结,不仅对矿区的后续找矿工作有重要的指导意义,而且对类似地区也有很好的借鉴作用。 相似文献
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By means of techniques such as inductively coupled plasma-mass spectrometry (ICP-MS) and X-ray fluorescence spectrometry (XRF),REE geochemical characteristics and depositional environment of the black shales in Baiguoyuan Ag-V deposit,Xingshan,Hubei Province,were studied in this work. The black shales in a typical TC5 profile of Doushantuo Formation of upper Sinian period were obviously enriched in REE,especially in LREE. The REE patterns of the investigated samples normalized by Post Archean Australian Shale (PAAS) showed a flat or slight rightward inclination. The characteristic elements,their ratio and correlation diagrams showed that it should be hot-water deposit and the black shale in the study area was of a sedimentary origin. Redox sensitive metal elements pattern,trace elements index measurement in anoxic environment,Ce anomaly and δEu negative anomaly showed that the deposit environment of the black shales was a reducing and anoxic one and a slight change of the sea level could be identified. The samples relatively focused on the superimposed area of sedimentary rock and basalt in the diagram of La/Yb-ΣREE and La/Yb-Ce/La. So there might be accession of hot-water sedimentation during the period of the formation of the black rock series,mostly in normal terrigenous sedimentation with the participation of deep hot-water deposit. 相似文献
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黔西北垭都-蠎硐断裂带为中国西南大面积低温成矿域的一个重要单元。断裂带分布众多铅锌矿床(点),矿床类型独特,区别于MVT型、VMS型及SEDEX型。笔者通过分析研究区铅锌矿床地质构造特征及Pb、Sr、S、REE等同位素-稀土地球化学特征认为:铅锌等金属成矿物质来源于基底,硫元素来源于上覆赋矿地层。铅锌矿床的成矿时代集中于200Ma^225Ma,为晚印支期,即铅锌矿的形成为峨眉山玄武岩喷发-喷溢事件晚期或者之后的成矿事件。研究区铅锌矿的成矿系统:受地幔柱及构造作用的影响,起源于基底的流体不断萃取基底变质火山岩中的铅锌等金属元素形成含矿流体,含矿流体被构造导入沉积地层后进行大规模运移,运移至蒸发岩层于构造的破坏空间卸载形成铅锌矿床。 相似文献
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The three kinds of soil formed by the weathering of the basalt in Yema village,Weining county of Guizhou province,the carbonate rock in Guiyang district and the phosphorite in the REE-bearing phosphate mining area in Zhijin county of Guizhou province were all rich in REE.The contents of LREE in these three soil were higher than that of HREE,which was caused by the different properties of LREE and HREE complexes.Since light REE could be easily absorbed by kaolinite grains,LREE was fully enriched in the process of desorption,migration and re-absorption,which formed a typical LREE soil.The chondrite normalized distribution models of those three types of REE-enriched soil are basically similar,which belong to the right deviation type,namely,rich in light rare earth element but short of heavy rare earth element,and showing Ce negative anomalies.Eu showed intense negative anomalies in the REE in the soil formed by the weathering of the sedimentary parent rocks(such as carbonate rock and phosphorite),while no pronounced Eu anomaly was found in the REE in the soil formed by the weathering of volcanic rocks(such as basalt).It is clear that though there were intense migration and enrichment of REE during the weathering process of rocks,no obvious differentiation of REE occurred and some features of the parent rocks were retained.That is why REE is of value in analyzing the source of materials. 相似文献