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云南因民铁铜矿区次火山杂岩主要由铁质熔岩、辉绿岩、辉长辉绿岩、火山集块岩、火山角砾岩、热液角砾岩等组成,岩相分带明显,热液蚀变与矿化关系密切。通过对次火山杂岩中不同岩相的黑云母和绿泥石电子探针结果分析得出,黑云母为镁质黑云母,大多数为再平衡黑云母,形成温度为505~590℃,lgf(O2)为-12.4~-5.25,压力为116~226 MPa,推测成岩深度为4.27~8.37 km,属于高温强氧化环境;绿泥石为密绿泥石、蠕绿泥石、透绿泥石、叶绿泥石,形成温度为170~235℃,lgf(O2)为-51.93~-43.70,lgf(S2)为-13.34~-2.50,属于中低温强还原环境。矿物产状、矿物组合与矿物中主要阳离子关系显示,两种矿物均具有多期多源性的特征。黑云母化蚀变代表铁矿的主成矿期,绿泥石化蚀变代表铜矿的主成矿期;多期次构造-岩浆-热事件形成了高-中低温的碱性强还原流体,叠加改造富集铁铜矿床,揭示了本区次火山杂岩是铁铜矿床稳定持续性成矿元素的供给系统。
The sub-volcanic complexes in the Yinmin Iron-Copper Mine in Yunnan Province are mainly composed of iron lava, diabase, gabbro, volcanic breccias, volcanic breccias and hydrothermal breccias, and the lithofacies zoning is obvious , Hydrothermal alteration and mineralization are closely related. Based on the analysis of the results of biotite and chlorite electron probe from different lithofacies in the subvolcanic complex, biotite is a magnesian biotite, most of which is rebalance biotite, with the formation temperature of 505-590 ℃, lgf (O2) is -12.4-5.25 and the pressure is 116-226 MPa. The diagenesis depth is estimated to be 4.27-8.37 km, which belongs to high temperature and strong oxidizing environment. Chlorite is dense chlorite, vermiculite and chlorite , Chlorite, the formation temperature is 170 ~ 235 ℃, lgf (O2) is -51.93 ~ -43.70, lgf (S2) is -13.34 ~ -2.50, which belongs to low-temperature strong reduction environment. Mineral production, mineral assemblages and the major cations in minerals show that both minerals have multi-period, multi-source characteristics. The biotitization alteration represents the main mineralization stage of the iron ores. The chloritization alteration represents the main mineralization stage of copper ores. The multistage tectonomagmaticthermal event forms a high-low temperature alkaline strong reduction fluid, By superimposing and rebuilding the iron-copper-rich ore deposits, it is revealed that the sub-volcanic complex in this area is a stable supply system of ore-forming elements for iron-copper deposits.