The Danizhuang copper deposit is a small porphyry deposit discovered from Luzong basin in recent years.The authors investigated wall rock alterations of the Danizhuang copper deposit on the basis of detailed field observations and petrographic and mineralogical studies,and revealed that the alterations include potassic alteration,beresitization and carbonatization.The characteristics of mineralization,the sequence of mineral deposition and the ore-forming stages,i.e.,potassium silicate stage,sulfide stage,carbonate stage,were determined.The sulfide stage can be further divided into quartz sulfide sub-stage and epidotechlorite sub-stage.The authors collected magmatic rocks (orthophyre) related to mineralization and obtained the age of (126.6±1.8 Ma) by LA-ICP-MS zircon U-Pb dating,which belongs to Early Cretaceous and was related to the intrusive activity of Shuangmiao Formation.Based on a comparison with similar deposits in other volcanic basins of eastern China,the authors discussed ore-control factors for the formation of this type of deposits,which provides reference for finding porphyry copper deposits in this area.%大倪庄铜矿是庐枞盆地内部近年来发现的一处小型斑岩型矿床.本次工作以大倪庄铜矿为研究对象,基于详细的野外观察和系统的岩相学、矿相学工作,总结了矿床的蚀变特征,即主要发育:钾硅酸盐化、黄铁绢英岩化、青磐岩化、碳酸盐化蚀变;确定了矿化特征、矿物生成顺序并划分了成矿阶段,即:钾硅酸盐化阶段、硫化物阶段、碳酸盐化阶段,其中硫化物阶段可进一步划分为石英硫化物亚阶段、绿帘石-绿泥石亚阶段.通过对与成矿有关的侵入岩体(正长斑岩)采用LA-ICP-MS锆石U-Pb定年,获得正长斑岩LA-ICP-MS锆石U-Pb年龄为(126.6±1.8) Ma,形成时代为早白垩世,对应于盆地内双庙旋回岩浆侵入活动.通过与其他区域相似矿床对比分析,探究了此类矿床控矿因素,为该地区斑岩型铜矿找矿勘查提供参考.
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