东天山自然铜矿成矿地质特征与成矿潜力分析

摘要

East Tianshan native copper mainly reserves in the late carboniferous Tugutubulake formation the overflow phase basalt and tuff,rock geochemistry show that the rock is divided into calcium alkaline Series and tholeiitic basalt series;High total rare earth,belong to the enrichment of light rare earth type,no Eu anomaly.REE distribution pattern as the typical tholeiite characteristics of rare earth element distribution,trace element analysis suggests that the diversity of basalt magma source material.Provenance discrimination diagram shows east tianshan basalt belongs to continental intraplate basalts or basalt tension belts;Basalt formed in the collision after stretching and partial melting of lithosphere mantle under the system of assimilation product of mixed with continental crust material.East tianshan formation by poor sulfur,weak oxidizing environment.Although the natural copper genetic type of East Tian shan is different with United States and Emei region.But the basalt type natural copper in East Tianshan is in good prospecting.%东天山自然铜主要赋存于上石炭统土古土布拉克组溢流相玄武岩及凝灰岩夹层中.岩石地球化学表明:该区岩石分为钙碱性系列和拉斑玄武岩两个系列,稀土总量较高,属轻稀土富集型,无Eu异常.REE分布模式具典型拉斑玄武岩稀土元素分布特征,微量元素暗示玄武岩岩浆物质来源具多样性.源区判别图解显示,东天山玄武岩属大陆板内玄武岩或陆拉张带玄武岩,形成于后碰撞拉伸作用下,为岩石圈地幔部分熔融与壳源物质发生同化混染的产物.东天山自然铜形成于贫硫、弱氧化环境,与美国基维诺和峨眉山地区的自然铜为不同成因类型.玄武岩型自然铜在东天山具很好找矿前景.