鄂西北耀岭河组超贫磁铁矿地质特征及找矿前景

Geological Characteristics and Prospecting Potential of Ultralow-grade Magnetite of Yaolinghe Formation in Northwestern Hubei

通过近几年的工作所取得的资料及在系统收集整理、综合分析前人资料的基础上,归纳总结鄂西北地区南华系耀岭河组超贫磁铁矿分布规律及成矿地质条件,探讨耀岭河组超贫磁铁矿的找矿前景。耀岭河组上段含铁岩系与贫磁铁矿体产出受火山喷发沉积控制,同时矿体富集又受火山喷发中心控制。耀岭河组上段火山喷发沉积岩具有旋回韵律性,旋回开始以喷溢沉积铁为主,晚期以爆发沉积铁为主,火山中心、近火山喷溢—爆发沉积的富钠质基性火山喷溢亚相的基性熔岩和爆发亚相的富钾贫钠的凝灰岩具有铁的成矿专属性,Fe含量一般与S iO2含量呈反比例的关系,属火山喷发沉积铁矿,类似于中国大红山式铁矿。鄂西北地区分布广泛的耀岭河组变质火山岩系为寻找超贫磁铁矿提供了巨大的找矿前景。

The authors summarize metallogenic geological conditions and distribution .law of Yaolinghe Formation of Nanhuan system and also discuss prospecting potential of uhralow-grade magnetite of Yaolinghe Formation. Iron-hearing rock series of the upper body in Yaolinghe group and occurrence of low-grade magnetite ore body are controlled by the volcanic eruption sediment, while ore enrichment also affected by the volcanic eruption center control. Volcanic eruption sedimentary rocks of the upper body in Yaolinghe group have periodicity and rhythmicility. The early stage is cycle of mainly extrusive sedimentary iron, the last stage is cycle with explosive sedimentary iron. have iron metallogenic specialization with an inverse proportion between iron content and the SiO2 in general, It belongs to volcanic eruption sedimentary iron ore, similar to Dahongshan style ironmine in China. Metamorphic rocks in Yaolinghe group widely distributed in northwestern Hubei which provide great prospecting for finding ultra-low grade magnetite. Based on the widely and systematically collected information in recent years and predecessor＇s research.