摘要
黄铁矿是砂岩型铀矿床中常见的载铀矿物之一,可为成矿提供有利的还原环境。以新疆蒙其古尔砂岩型铀矿床含矿目的层中黄铁矿为研究对象,通过偏光显微镜观察与电子探针微区化学成分分析方法相结合进行研究。结果表明:区内含矿目的层中出露有三种不同形态的黄铁矿,即草莓状黄铁矿、立方体自形晶黄铁矿和不规则状黄铁矿,它们在结晶形态、赋存形式及化学成分方面均有所不同;其硫铁平均比值显示为S/Fe(草莓状)<S/Fe(立方体自形晶)<S/Fe(不规则状),化学成分总体呈现出富Mo、As、Co,贫Ni、Pb、Se、Zn、Ag、Sb。另外在铀成矿过程中,不规则状黄铁矿与铀矿物的分布存在密切关系,为成矿流体提供了必要的还原剂,继而为区内含矿目的层中铀的富集提供了有利条件。
Pyrite is one of the most common uranium-bearing minerals in sandstone-type uranium deposits,which can provide favorable reduction environment for mineralization.The pyrite in the ore target layer of the Mongqigur sandstone-type uranium deposit in Xinjiang is taken as the research object,and polarization microscope and EPMA were used to study the chemical composition.The results show that there are three different forms of pyrite in the ore target layer,namely strawberry pyrite,cubic euhedral crystal pyrite and irregular pyrite,which are different in crystal morphology,occurrence form and chemical composition.The average ratio of sulphur to iron is S/Fe(strawberry pyrite)<S/Fe(cubic euhedral crystal pyrite)<S/Fe(irregular pyrite).The chemical composition is rich in Mo,As,Co and poor in Ni,Pb,Se,Zn,Ag and Sb.In addition,in the process of uranium mineralization,irregular pyrite is closely related to the distribution of uranium minerals,which provides the necessary reducing agent for ore-forming fluids,and then provides favorable conditions for uranium enrichment in ore target layer in the area.
作者
黄广文
黄广楠
何钟强
潘家永
HUANG Guang-wen;HUANG Guang-nan;HE Zhong-qiang;PAN Jia-yong(Qinghai Province Key Laboratory of Geological Process and Mineral Resources of Northern Qinghai-Tibet Plateau,Qinghai Geological Survey Institute,Xining 810012,China;No.105 Exploration Team,Qinghai Bureau of Coal Geological Exploration,Xining 810007,China;Qinghai Institute of Hydro-geology and Engineering Geology and Environmental Geology,Xining 810008,China;State Key Laboratory of Nuclear Resources and Environment,East China University of Technology,Nanchang 330013,China)
出处
《科学技术与工程》
北大核心
2019年第33期68-75,共8页
Science Technology and Engineering
基金
国家自然科学基金重点项目(U1403292)
青海省青藏高原北部地质过程与矿产资源重点实验室开放课题(2019-KY-04)
青海省区域地质调查与片区总结项目(12120114079701)资助
关键词
含矿目的层
电子探针
黄铁矿
化学成分
蒙其古尔
ore target layer
electron probe microanalysis
pyrite
chemical composition Mengqiguer
