云南普朗斑岩铜矿床矿石矿物特征及成矿期期次研究

Study on Ore Mineral Characteristics and Metallogenic Stages of Pulang Porphyry Deposit,Yunnan Province

为进一步查明普朗铜矿矿床成因,通过收集、分析普朗铜矿区最新的勘探资料和生产资料,对矿床地质特征、矿石矿物特征等进行系统研究。结果表明:硫化矿中金属矿物主要为黄铜矿、黄铁矿、磁黄铁矿及方铅矿,脉石矿物主要为石英、长石、绢云母,造岩矿物为角闪石、黑云母、斜长石。矿床严格受控于岩浆岩、构造和围岩蚀变,自岩体中心往外发育强钾化硅化带(工业铜矿带)→绢英岩化带(铜矿化带)→青磐岩化带(基本无矿化)。结合矿床地质特征、矿物共生组合及矿物穿插交代关系等,将矿床划分为岩浆晚期、热液硫化物期和表生期,其中热液硫化物期为主要成矿期,矿床总体属次火山—热液斑岩型铜矿床,外围北部铅锌矿体、东矿段大脉状铜矿体为与次火山作用相关的热液型矿床。

In order to ascertain the ore genesis of Pulang copper deposit,the geological characteristics of deposit and ore mineral are studied systematically,based on collection and analysis of latest exploration data and existing copper mine production data.The results show that the main metal minerals of sulfide ore are chalcopyrite,pyrite,pyrrhotite and galena,the main gangue minerals are quartz,feldspar and sericite.In addition,the rock-forming minerals are including hornblende,biotite and plagioclase.The Pulang copper deposit is strictly controlled by magma,structure and wall rock alteration,and developed the alteration zoning of potassic-silicified zone(industrial copper ore zone)→sericite-quartz alteration zone(copper mineralization)→propylitization alteration zone(no mineralization).According to geological features,mineral association and mineral metasomatic relations,the mineralization of Pulang copper deposit can be divided into late-magmatic stage,hydrothermal sulfide stage and supergene stage.The hydrothermal sulfide stage is the main mineralization stage.Generally,the deposit is belongs to sub-volcanic hydrothermal porphyry copper deposit,and the lead-zinc ore in northern surrounding regions and vein copper deposit in eastern regions are belongs to hydrothermal type deposit which correlated to sub-volcanism.