广东新丰县铁帽顶铁矿地质特征及成矿模式研究

Study on Geological Characteristics and Metallogenic Model of Tiemaoding Iron Ore in Xinfeng County,Guangdong Province

铁帽顶矿区位于华南大陆向南凸出的边缘地带,濒临南海,地质构造基本上被北东向的新华夏-华夏系扭动构造体系控制。为进一步了解铁帽顶矿区的成矿原理,通过总结矿区的地质特征,利用矿区主要岩石、矿石化学分析结果研究其对应的岩石地球化学特征,并收集矿区所在的石背岩体近年来的测年数据,综合分析其成矿模式。矿区的铁矿体赋存于花岗岩和碳酸盐岩接触带内的变质岩带中,岩石地球化学特征及矿区地质特征显示矿石原岩为火山沉积岩,成矿时代为早侏罗世晚期-中侏罗世早期;铁帽顶铁矿其形成过程为浅海相富铁质钙质沉积—火山喷发溢出—热液改造,属海相火山沉积-热液改造的矽卡岩型铁矿床。

The Tiemaoding mining area is located at the edge of the South China continent,near the South China Sea,and its geological structure is basically controlled by the northeastward Neocathaysian and Cathaysian twisting tectonic system.In order to further understand the metallogenic principle of Tiemaoding mining area,this paper summarizes the geological characteristics of the mining area,studies the corresponding geochemical characteristics of the rocks by using the chemical analysis results of the main rocks and ores in the mining area,and collects the dating data of the Shibei rock mass where the mining area is located in recent years to comprehensively analyze its metallogenic model.The iron ore body exists in the metamorphic rock zone in the contact zone of granite and carbonate rock.The geochemical characteristics of the rock and the geological characteristics of the mining area show that the ore source rock is volcanic sedimentary rock and the metallogenic age is late Early Jurassic to early Middle Jurassic.The formation process of iron-rich calcareous deposit in shallow Marine facies-volcanic eruption and overflow-hydrothermal transformation is a skarn type iron deposit of Marine volcanic deposition-hydrothermal transformation.