内蒙古乌拉特中旗依肯脑包石墨矿地质特征及成因

内蒙古乌拉特中旗依肯脑包石墨矿为一套角闪-绿片岩相的区域变质岩系,矿区构造以褶皱构造和脆性断裂为主,形成该区的构造格架。矿区地层主要为色尔腾山岩群东五分子岩组二岩段,矿体分布受层位控制,呈层状、似层状,部分为透镜状,其产状与围岩一致。通过地质填图、探槽揭露、激电异常等方法,最终圈定出6条石墨矿(化)体,其走向呈北西向,矿体平均品位在3.97%~4.77%之间。该矿的成矿物质与东五分子岩组(二云)石英片岩同时沉积,片岩中赋存的成矿物质经3期区域变质作用形成晶质石墨。因此,该矿床属区域变质型晶质石墨矿。

Geological characteristics and genesis of the Yikennaobao graphite deposit in Urad Middle Banner, Inner Mongolia

The Yikennaobao graphite deposit in Urad Middle Banner of Inner Mongolia is a series of regional metamorphic rocks of amphibolite-green schist. It mainly consists of fold structure and brittle fracture. The deposit occurs in the quartz schist the second member of the Dongwufenzi Formation-complex in the Seertengshan Group-complex. Its ore body is stratiform, stratoid, partly lentoid, whose distribution is controlled by strata and whose occurrence is similar with country rock. By geological mapping, trenches revealing and induced polarization anomalies, the paper delineated six northwest-trending graphite ore bodies. Their average grade is between 3.97%-4.77%. Their ore-forming materials are simultaneously deposited with (two mica) quartz schist of the Dongwufenzi Formation-complex. After three regional metamorphism, the ore-forming materials gradually formed crystal graphite. Therefore, the deposit is a kind of regional metamorphic crystal graphite.