四川牦牛坪稀土矿床萤石Sr、Nd同位素对地幔成矿流体的指示意义

萤石是四川牦牛坪稀土矿床主要的脉石矿物之一，其形成贯穿了整个稀土成矿过程，因此同位素的研究对探讨萤石和稀土成矿流体的来源具有重要的价值。矿区6件萤石样品的Sr、Nd同位素组成没有明显差异，结合围岩（碳酸岩－正长岩，花岗岩）同位素组成特征研究表明，不同颜色、来自不同矿石类型、具有不同REE类型的萤石为同源产物，稀土成矿流体来源于富集地幔，与区内碳酸岩－正长岩岩浆活动密切相关。     

广西钟山县花山矿区南矿段稀土矿矿石品质特征分析

花山矿区南矿段稀土矿矿石为中低品位为主的花岗岩风化壳离子吸附型稀土矿石,属于轻稀土富集型,且Eu具有明显的负异常,其稀土配分特征表现出了与原岩的明显继承性。花岗岩原岩风化程度越高,风化壳厚度越大,矿层的品质就越好,浸取率也相应增高。全风化层是稀土矿的主要赋矿层位,全风化层的顶部稀土氧化物含量不高,稀土元素主要富集在全风化层的中下部。矿体轻重稀土的比值由地表向下,比值降低,即表现出明显的矿层上部富集轻稀土,下部富集重稀土。     

新疆梧南金矿床地质与地球化学特征

梧南金矿床是产于碳酸盐岩地层的微细粒浸染型金矿类型.文章介绍了矿区地质背景、矿床地质特征,矿石、围岩的稀土配分曲线呈富轻稀土的右倾型,曲线形态基本一致.表明矿石对围岩的继承性,酸性斑岩也为成矿提供了一定的热源和部分含矿热液.石炭系碳酸盐岩成为金矿化的有利围岩,矿区构造运动使含金岩层进一步活化浸出、热液交代和迁移富集.     

兰坪—思茅盆地地层及铜矿床REE地球化学研究

对兰坪－思茅盆地中－新生代沉积岩、石炭纪玄武岩、铜矿石、铜矿物、铜矿脉石矿物和钙华的ＲＥＥ研究表明，存在三种稀土分布模式。种类沉只岩和绝大多数铜矿石、铜矿物属轻稀土富集型，铜矿脉石矿物及钙华主要属中稀土富集型，玄武岩和极少数铜矿石属轻稀土弱富集型。研究结果指出，本区铜矿的成矿物质主要来自沉积岩，部分与基底火山岩有关。     

青海锡铁山热水沉积型铅锌矿床的地球化学特征

通过对锡铁山铅锌矿床的围岩(矿石)化学成分、稀土及微量元素特征的研究，发现矿区地层普遍具有铈负异常(δCe=0．47～0．90)，为海相沉积岩，近矿围岩中Ag、Hg、As、Sb、Ba等热水沉积指示元素偏高，显示成矿流体性质为热卤水，矿区火山岩不发育，矿床类型可以划为Sedex型。     

甘肃夏河三索玛金矿地质特征及找矿标志

本文简要回顾了干沙鄂博稀土矿的发现与勘查历程;认为海西晚期碱性斑岩体的侵入及其以萤石化、碳酸盐化、硅化、重晶石化为主的面型蚀变,放射性异常和La、Ce为主的化探异常是矿区的主要找矿标志;通过以碱性斑岩体的产出面积、矿化深度、含矿率等为主的预测标志的定性预测,认为矿区具有大型稀土型矿床成矿前景;从地质、地球化学、重砂异常综合信息的初步分析,矿区外围具有稀土及多金属矿的勘查前景。     

问与答

答:铀矿的顺便检查,是指在进行区域地质调查和矿区普查勘探以及矿床开采时,用辐射仪对岩石、矿石及地下水资源,进行放射性强度测量,然后将测量资料按规定要求进行综合整理,说明该地区有没有放射性铀存     

广东梅县玉水多金属矿矿床成因探讨

本文在对比分析矿区火成岩（围岩）及含矿段岩矿石稀土元素、微量元素的基础上,结合矿石稳定同位素及包裹体特征对矿床成因作了探讨。根据本区微量元素性状及其分布特征,指出了含矿段火成岩与矿区内脉状火成岩侵人体（β_μ及γ_π）及上侏罗统火成岩的微量元素特征差异,同时认为：矿床是由局部火山喷气并受中温热液改造而成,含矿段矿化火山岩是由特定火山喷气作用形成的产物,它与区内的脉状火成岩侵人体及上侏罗统火山岩之间没有成因联系,对矿床改造作用的中温热液,主要来自深部隐伏碱性侵人体。     

某碱性花岗岩稀有稀土矿床的矿物及地球化学特征

某碱性花岗岩稀有稀土矿床(801矿),是吉林省地质局区测队1975年进行1∶20万区域地质调查时通过放射性测量发现的.该矿是国内首次发现的一种新类型工业矿床,矿石品位富,稀有稀土元素种类多,矿化深度大.笔者研究了矿床中稀有稀土元素矿物及其地球化学特征,并运用数学方法统计了元素的空间分布特点及各成分间的关系,现简述如下.矿区及矿床地质简述矿区位于某隆起带,东西向压性断裂及两条华夏式大断裂之间.区内局部出露古生代海相砂页岩及火山岩,大面积出露中生代火山碎屑岩,主要为侏罗系呼日格组、付家洼组、宝石组等一套     

论570矿床稀土元素特征及地球化学演义

本文对５７０矿床新鲜岩石、蚀变岩石的稀土元素进行了地球化学研究。稀土元素特征表明，矿区基底花岗岩的成因类似华南改造型花岗岩；火山岩可能是基底变质深熔作用形成；次花岗斑岩与火山岩同源。在弱酸性一中性热液蚀变（赤铁矿化和水云母化）过程中，稀土元素的变化不大，仅表现变稀土总量有所增减，而碱性蚀变（碱交代和碳酸盐化）则一方面表现出稀土总量的变化，另一方面轻，重稀土的分馏程度也有变化。矿石中稀土总量，特别是     

加强地勘、深化选冶、着力应用──四川稀土产业发展战略初步思考

本文在分析四川稀土资源概况、稀土产业现状的基础上。提出了四川稀土产业发展战略构想和稀土产业政策建议。     

广东禾尚田矿区新类型风化壳离子吸附型稀土矿的发现及意义

在广东禾尚田矿区,通过地表和钻孔岩芯样品的野外硫酸铵浸泡-草酸点滴试验、化学分析、稀土（REE）配分分析、稀土浸取率测定等工作,首次发现了灰岩风化壳中存在离子吸附型富铕稀土工业矿床。稀土矿与坡残积钨锡矿、铷矿共伴生,并伴生锂、镓和铯等元素,具有中稀土富集和高浸取率的特点,是离子吸附型稀土矿的新类型。它的发现将对离子吸附型稀土矿床勘查产生深远的影响,大大拓展找矿思路和对象;并说明了在一个矿田或一个矿区内寻找新的矿种、新的矿床类型、新的含矿层位的重要性。通过成矿地质条件分析,作者认为矿区西部找矿前景甚佳,禾尚田矿区将成为一个集有色、稀有、稀土、贵金属矿产的多矿种、多矿床类型、多含矿层位的矿区。     

河南省西峡县太平镇稀土矿床地质特征及找矿远景研究

太平镇稀土矿床是河南省首个新发现的中型稀土矿床,填补了河南省稀土矿的空白。通过近几年的勘查在该矿区共发现稀土矿化带7条,圈出稀土矿体17个,估算稀土氧化物总量超过17×104 t。文章通过系统梳理分析太平镇稀土矿床的矿区地质、矿体特征,基于详细野外调研及室内测试分析认为:(1)太平镇稀土矿床是以Ce、La、Nd、Pr为主的轻稀土矿矿床,最主要的矿石矿物为氟碳铈矿;(2)稀土矿体严格受北西向构造破碎带控制,围岩为加里东期斜长花岗岩和二郎坪群火神庙组变质岩;(3)放射性及萤石矿、金矿等采矿遗迹,围岩硅化、黄铁矿化、萤石化、重晶石、绢云母化和褐铁矿化,石英-方解石-辉钼矿、石英-重晶石-方解石-氟碳铈矿-黄铁矿、石英-萤石-重晶石-氟碳铈矿、褐铁矿-褐帘石-黄铁矿-蓝铜矿-氟碳铈矿-萤石-重晶石-方解石矿物共生组合是找矿标志;(4)太平镇-板山坪复式背斜核部附近发育加里东期张性断裂带的部位是寻找太平镇式稀土矿的远景区。     

论东川脉状富铜矿的历史和现实意义

东川脉状富铜矿在历史上对矿山、对国家曾作出过重大贡献。汤丹厚大的层状铜矿也是５０年代在广泛调查汤丹脉状矿的基础上发现的，从而肯定整个东川矿区层状矿的巨大工业价值。对脉状铜矿的成因，长期以来受着“脉状铜矿由层状铜矿就地取材”转化形成的思想束缚，因而对其评价－研究成果甚少。从脉矿现有的历史资料出发，结合当今的研究成果，认为东川矿区广泛分布含铜大于５％的富脉矿，脉矿与层状矿在伴生元素、稀土配分、硫同位素组成，爆裂测温等方面，二者均有明显的区别。脉铜矿是以深源为主形成的。建议对历史上曾开采，但至今未作详细地质工作的茂麓铜厂尽快予以评价。     

Sea-floor exhalative sedimentary and magmatic hydrothermal superimposition on the Bainiuchang polymetallic deposit in Yunnan Province： REE geochemical evidence

In order to study the characteristics of sea-floor exhalative sedimentary and magmatic hydrothermal superimposition on the Bainiuchang polymetallic deposit, the REE compositions of the granites, host-rocks and ores have been systematically analyzed by ICP-MS. As viewed from their REE compositions, the granites show obvious negative Eu anomalies and weak negative Ce anomalies. According to their REE characteristics, the host-rocks were derived partly from sea-floor exhalative sediments. In terms of their REE compositions, the ores can be divided into two groups: one group, of which the samples were collected from the Baiyang segment relatively far away from the Bozhushan granite batholith, possesses positive Eu anomalies or no Eu anomaly and negative Ce anomalies, indicating that ore-forming hydrothermal fluid was relatively reductive and its temperature was higher than 250 ℃. Furthermore, the coinstantaneous presence of positive Eu anomalies and negative Ce anomalies indicate that the convective mixing of a little amount of seawater with hydrothermal fluid had happened while ores were precipitated on ancient sea floor. The other group, of which the samples were mainly collected from the Chuanxindong and Duimenshan segments near the Bozhushan granite batholith, has similar chondrite-monalized REE distribution patterns to those of the magmatic rocks. But as a whole, the REE characteristics of both groups change gradually starting from the Bozhushan granite batholith. Based on the REE characteristics of the granites, host-rocks and ores, it is suggested that the ore-forming metals seem to have come from several different sources.     

西藏洞中拉铅锌矿床稀土元素地球化学特征

通过对洞中拉铅锌矿床稀土元素的研究,判定矿石与地层（灰岩）有着相似的稀土元素特征,同时矿石与侵入岩也有着密切的关系。矽卡岩全岩的稀土元素分布模式表现出承袭了侵入岩的分布模式。稀土元素相关的特征值变化表明,在成矿过程中,成矿温度逐渐降低,成矿环境从相对还原的条件向相对氧化的条件改变。     

Rare earth elements in apatite and magnetite in Kiruna-type iron ores and some other iron ore types

An investigation of the content and distribution of REE in apatite and magnetite in the iron ores of Kiruna type and some other iron ores is presented. REE in apatite and magnetite in different ore types show characteristic patterns which are related to different modes of formation of the ores.The magnetite-apatite iron ores of the world can be divided into two types: (a) Kiruna iron ores proper which occur in volcanic rocks, and (b) iron ores connected with deuteric processes and/or related to intrusive rocks. Apatite of the Kiruna ores proper in Fennoscandia (e.g. Kiirunavaara, Malmberget and Grängesberg) shows a common pattern with 2000–7000 ppm REE, a weak to moderate LREE/HREE fractionation and negative Eu anomalies. In the Kiruna area, apatite of the main, P-poor ores and of the later, hydrothermal-exhalative P-rich ores, have the same REE distribution which indicates a common source. There is a similar REE distribution in magnetite-apatite trachytic-rhyodacitic host rock which confirms a close magmatic relationship. Apatite in phosphorites (such as the Paleoproterozoic Påläng deposit in northern Sweden) has a different composition (< 1000 ppm REE with Ce depletion) which excludes a sedimentary origin of the Kiruna apatite.Apatite in other volcanogenic magnetite-apatite ores outside Fennoscandia differ by a stronger LREE/HREE fractionation and by a medium to large Eu depletion, partly indicating a relationship to alkaline intrusions. The Avnik apatite, Turkey, shows a weak differentiation in combination with a pronounced negative Eu anomaly, indicating provenance from silicic magmatic sources.The REE pattern of apatite in the deuteric-hydrothermal apatite-bearing iron ores is in general similar to that of apatite in the Kiruna iron ores proper. The similarity indicates a common process of formation for both ore types.The apatite-iron ores of the Kiruna type proper were formed by a late-magmatic differentiation. The ores of the Kiruna area are, in similarity with some other magnetite-apatite ores, emplaced along regional fracture-fault lines and close to an older basement. In general the REE pattern of apatite in the different deposits shows an affinity to alkaline or sub-alkaline magmas, indicating a rifting environment. The alkaline, trachytic volcanics hosting the Kiruna ores in northern Sweden are clearly related to an extensional setting where rifting was important. A probable source for this large-scale ore-forming process was partial melting of deep-seated rocks. The ores evolved in an intracontinental setting with magma generation caused by underplating of older crust.The process giving rise to magnetite-apatite ores of the Kiruna type has occurred during the time span from Paleoproterozoic to Tertiary. The Proterozoic ores occur mainly in cratonized areas, whereas the younger ones occur in fold belts. The amount of ore formed in post-Proterozoic time is as large as that formed in Proterozoic time.     

Geochemical Characteristics and Genetic Significance of Datangpo‐Type Manganese Ore Deposits during the Cryogenian Period

The Datangpo‐type manganese ore deposits, which formed during the Nanhuan (Cryogenian) period and are located in northeastern Guizhou and adjacent areas, are one of the most important manganese resources in China, showing good prospecting potential. Many middle‐to‐large deposits, and even super‐large mineral deposits, have been discovered. However, the genesis of manganese ore deposits is still controversial and remains a long‐standing source of debate; there are several viewpoints including biogenesis, hydrothermal sedimentation, gravity flows, cold‐spring carbonates, etc. Geochemical data from several manganese ore deposits show that there are positive correlations between Al₂O₃ and TiO₂, SiO₂, K₂O, and Na₂O, and strong negative correlations between Al₂O₃ and CaO, MgO, and MnO in black shales and manganese ores. U, Mo, and V show distinct enrichment in black shales and inconspicuous enrichment in Mn ores. Ba and Rb show strong positive correlations with K₂O in manganese ores. Cu, Ni, and Zn show clear correlations with total iron in both manganese ores and black shales. ∑REE of manganese ores has a large range with evident positive Ce anomalies and positive Eu anomalies. The Post Archean Australian Shale (PAAS) normalized rare earth element (REE) distribution patterns of manganese ores present pronounced middle rare earth element (MREE) enrichment, producing “hat‐shaped” REE plots. ∑REE of black shales is more variable compared with PAAS, and the PAAS‐normalized REE distribution patterns appear as “flat‐shaped” REE plots, lacking evident anomaly characteristics. δ¹³C values of carbonate in both manganese ores and the black shales show observable negative excursions. The comprehensive analysis suggests that the black shales formed in a reducing and quiet water column, while the manganese ores formed in oxic muddy seawater, which resulted from periodic transgressions. There was an oxidation–reduction cycle of manganese between the top water body and the bottom water body caused by the transgressions during the early Datangpo, which resulted in the dissolution of manganese. Through the exchange of the euphotic zone water and the bottom water, and episodic inflow of oxygenated water, the manganese in the bottom water was oxidized to Mn‐oxyhydroxides and rapidly buried along with algae. In the early diagenetic stage, Mn‐oxyhydroxides were reduced and dissolved in the anoxic pore water and then transformed into Mn‐carbonates by reacting with HCO₃^? from the degradation of organic matter or from seawater. In the intervals between transgressions, continuous supplies of terrigenous clastics and the high productive rates of organic matter in the euphotic zone resulted in the deposition of the black shales enriched in organic matter.     

Discovery of the REE minerals and its geological significance in the Quyang bauxite deposit,West Guangxi,China

Most of the karstic bauxite deposits in China are enriched in REE, and the REE has commonly been considered to be adsorbed on the surface of clay or diaspore minerals as ion state. However, occurrence of REE minerals in the bauxite deposits has not been reported by far. In the Quyang bauxite deposit from Guangxi province, we find REE minerals. The minerals are parisite and churchite. Parisite is widely distributed in the ooids and matrix, inducing positive Ce anomaly of the ores; whereas, churchite is rare and occurred in the core of ooid. The compositions of the REE minerals show the Eu anomaly can change gently during the weathering, and the Eu anomaly analyses suggest that the REE in the ores are mostly derived from the underlying carbonates. The parisite is formed in an alkaline condition, while churchite in an acidic situation; the co-existence of the two minerals in the ores suggests the Permian environment for bauxite formation is complex with great change of pH value. Moreover, parisite is inferred to be formed earlier than the churchite.     

滇东富乐铅锌矿区地层稀土元素地球化学

通过对罗平富乐铅锌矿区地层及矿石进行了稀土元素地球化学特征对比研究.结果显示,梁山组样品 ΣREE值25.91×10-6~108.40×10-6,δEu值0.35~0.73,δCe值0.64~1.35.具Eu负异常和Ce弱正异常;阳新组碳酸盐岩样品 ΣREE值0.82×10-6~6.75×10-6,δEu值0.15~0.97,δCe值0.22~0.62,具Eu负异常和Ce负异常;玄武岩样品 ΣREE值204.17×10-6~290.57×10-6,δEu值变化范围0.91~0.97,δCe值1.02~1.03,Eu异常和Ce异常不明显.峨眉山玄武岩、阳新组、梁山组岩石与矿石REE配分模式比较区别明显,暗示成矿物质并非这些地层提供另有其它来源;梁山组及含矿地层阳新组样品为轻稀土富集型,并具有Eu负异常,暗示地层可能形成于被动大陆边缘还原环境.