安徽泾县湛岭斑岩型钼矿床中铼的赋存状态研究  

The occurrence of rhenium in the Zhanling porphyry molybdenum deposit,Jing County,Anhui Province

作　　者：陈雪锋[1,2] 范裕 周涛发[1,2] CHEN XueFeng;FAN Yu;ZHOU TaoFa(School of Resources and Environmental Engineering,Ore deposit and exploration Centre(ODEC),Hefei University of Technology,Hefei 230009,China;Anhui Province Engineering Research Center for Mineral Resources and Mine Environments,Hefei 230009,China)

机构地区：[1]合肥工业大学资源与环境工程学院,合肥工业大学矿床成因与勘查技术研究中心(ODEC),合肥230009 [2]安徽省矿产资源与矿山环境工程技术研究中心,合肥230009

出　　处：《岩石学报》2021年第9期2705-2722,共18页Acta Petrologica Sinica

基　　金：国家自然科学基金项目(41872081、91962218);中央高校基本科研业务费专项(PA2019GDZC0093)联合资助.

摘　　要：铼(Re)作为关键金属之一,是国家安全和军事战略必不可少的关键矿产,近年来受到世界各国的广泛关注。目前全球90%的Re产出于斑岩型矿床中,由于Re和Mo(钼)的元素性质相近,辉钼矿是Re的主要富集矿物。目前,前人的研究主要集中于含Re辉钼矿多型、辉钼矿中Re的含量、以及微米尺度上Re在辉钼矿中的赋存规律等方面,但纳米尺度上,Re在辉钼矿中的赋存状态研究仍十分薄弱。本次工作以安徽省泾县新发现的湛岭斑岩型钼矿床中的辉钼矿为研究对象,查明矿床中的辉钼矿主要有两种类型:粗粒叶片状辉钼矿(Ⅰ型)和细粒集合体辉钼矿(Ⅱ型)。通过电子探针(EPMA)和激光剥蚀电感耦合等离子质谱仪(LA-ICP-MS)确定了微米尺度上辉钼矿中的Re含量呈较大的不均一性。粗粒叶片状辉钼矿核部的Re含量(90.2×10^(-6))高于边部(37.6×10^(-6)),细粒集合体辉钼矿中的Re平均含量(89.4×10^(-6))明显高于粗粒叶片状辉钼矿(50.0×10^(-6)),其中可见多个无规律的局部Re富集区域。在此基础上,对细粒集合体辉钼矿中富Re区域进行聚焦离子束(FIB)原位取样,并运用透射电镜(TEM)分析发现,在纳米尺度上,辉钼矿Re含量也有较大不均一性。在ADF-TEM照片中识别出辉钼矿具有a、b两种不同的表征。表征a的辉钼矿Re含量较高,晶格受到明显干扰,除类质同象替换外,还存在以Re-S吸附的方式赋存的Re;而表征b中的辉钼矿Re含量较低,晶格并未受到明显的干扰,Re主要是以类质同象替换的形式存在。以上研究结果表明,湛岭斑岩型钼矿床中的Re除了类质同象替代Mo进入辉钼矿晶格外,还以Re-S的形式吸附在辉钼矿晶格表面,Re的两种赋存状态是辉钼矿中Re含量不均一性的主要原因。Rhenium(Re)as one of the significant critical metals and essential for national security and military strategies.It has attracted extensive attention in recent years.At present,90%of Re resources was produced in porphyry deposits in the world.Re is mainly enriched in molybdenite,due to the similar element properties of Re and Mo(molybdenum).However,the nanoscale occurrence and enrichment mechanisms of Re in molybdenite is still need to be further studied.This work focuses on the molybdenite in the newly discovered Zhanling porphyry molybdenum deposit in the Jiangnan uplift belt.The molybdenite is the main rhenium-bearing mineral with two types,such as coarse-grained leaf-shaped molybdenite(Type-Ⅰ)and fine-grained aggregate molybdenite(Type-Ⅱ)which is slightly later.LA-ICP-MS trace element analysis results showed that the Re average contents in the Type-Ⅱ(89.4×10^(-6))is significantly higher than that Type-Ⅰ(50.0×10^(-6)),but the Re shows obvious irregular enrichment in the individual grain of Type-Ⅰ.Generally,the contents of Re is higher in the core(89.4×10^(-6)),but lower in the edge(37.6×10^(-6)).Through TEM observation on the Re-rich regions in the Type-Ⅱ,two different characteristics of molybdenite has been recognized in the ADF-TEM photos.The characterization a of molybdenite has a relatively high Re contents.Besides isomorphic substitution in the lattice of molybdenite,Re atoms also occur as Re-S adsorption form exist in molybdenite.While the characterization b of molybdenite shows a relatively lower Re contents and Re mainly exists in the form of isomorphic substitution.Therefore,we emphasize that most of Re substituted Mo in the molybdenite crystal lattice,and few Re can be adsorbed on the surface of the molybdenite crystal as the Re-S form,which resulting the Re microheterogeneity in molybdenite.

关 键 词：铼 赋存状态 透射电镜 湛岭斑岩型钼矿床 

分 类 号：P618.65[天文地球—矿床学] P618.87[天文地球—地质学]