云南哈播斑岩铜(-钼-金)矿床流体包裹体研究  

Fluid inclusions of Habo porphyry Cu-(Mo-Au) deposit,Yunnan Province

作　　者：祝向平[1] 莫宣学[2] Noel C WHITE 孙明祥 赵思礼 

机构地区：[1]成都地质矿产研究所,四川成都610081 [2]中国地质大学地球与资源学院,北京100083 [3]ARC Center of Excellence in Ore Deposit, University of Tasmania, Hobart, Tasmania, 7001, Australia [4]Asia Now Resources Corp.,云南昆明650021

出　　处：《矿床地质》2012年第4期839-849,共11页Mineral Deposits

基　　金：国家重点基础研究发展计划(973计划)项目(编号:2009CB421002、2002CB412600);高等学校创新引智计划(“111计划”);“成矿动力学基地”(B07011);国家基金项目(编号:40873023、40830317);国家地调项目(1212010610104)资助成果

摘　　要：哈播斑岩Cu-(Mo-Au)矿床产于哀牢山富碱斑岩带的南段,形成于青藏高原后碰撞阶段构造转换环境,属于陆-陆碰撞型斑岩矿床。根据脉体的交切关系,确定哈播矿床各种脉的演化序列为早期石英脉→石英-黄铜矿脉→石英-辉钼矿脉。脉中流体包裹体的岩相学、显微测温和激光拉曼光谱分析等研究结果显示,各期脉中均有富气相包裹体、富液相包裹体和含子矿物多相包裹体,各种包裹体的气相均含有CO2、SO2、H2O等气体。各期脉中多种包裹体并存并具有相似的均一温度范围,富液相包裹体均一温度149～427℃,盐度w(NaCleq)6.0%～15.0%;富气相包裹体均一温度205～405℃,盐度w(NaCleq)3.4%～19.0%;含子矿物多相包裹体均一温度305～516℃,盐度w(NaCleq)33.5%～61.0%。哈播矿床的初始成矿流体由稳定共存、不混溶的低盐度流体和高盐度流体组成,高盐度流体是哈播矿床成矿元素迁移的主要载体。成矿流体在400℃左右发生"二次沸腾"、分相,温度下降和挥发分持续逃逸可能是Cu-Au成矿的诱因。Mo元素在成矿流体多次沸腾、分相过程中,持续优先分配进入高盐度流体中而逐步富集;温度下降,使含钼硫化物在流体中溶解度降低、沉淀,形成石英-辉钼矿±黄铜矿脉。The Habo porphyry Cu-（Mo-Au） deposit is located in the south of Jinshajiang-Ailaoshan orogenic belt.It is a typical post-subduction porphyry deposit formed in a Tibetan post-collision transformation setting.Intense K-feldspar and biotite alteration associated with quartz stockwork occurs in the Habo deposit alteration center,which is surrounded and overprinted by later feldspar-destructive alteration.Several stages of veinlets can be observed,and the evolution sequence of vein types is magnetite-quartz veinlets→early quartz veinlets→quartz-chalcopyrite veinlets→quartz-molybdenite veinlets→quartz-sericite-pyrite veinlets →pyrite-chalcopyrite veinlets.Early quartz,quartz-chalcopyrite and quartz-molybdenite veinlets were selected to perform fluid inclusion study.The cathodoluminescence images of early quartz,quartz-chalcopyrite and quartz-molybdenite veinlets indicate that they all were overprinted by later hydrothermal fluids.Vapor-aqueous inclusions,aqueous inclusions,and high brine halite-bearing inclusions were found in all the three types of veinlets,and CO2-bearing inclusions were found locally.Using Laser Raman analysis,the authors found that CO2 and SO2 are very abundant in all these inclusions.In early quartz,quartz-chalcopyrite and quartz-molybdenite veinlets,vapor-aqueous inclusions were homogenized within 149～427℃ with salinity w（NaCleq） of 6.0%～15.0%,aqueous inclusions were homogenized within 205～405℃ with salinity w（NaCleq） of 3.4%～19.0%,and high brine halite-bearing inclusions gained homogenization within 305～516℃ with salinity w（NaCleq） of 33.5%～60.8%.Vapor-aqueous and high brine halite-bearing inclusions are abundant in early quartz veins,and their homogenization temperatures are similar,which shows that in the Habo deposit the silicate melt directly exsolved two coexisting fluid phases,a vapor and a hypersaline liquid,and the hypersaline fluid is the main carrier of metals.When the fluids migrated upward,at the temperature of ～400℃,the hypersaline liq

关 键 词：地球化学 流体包裹体 流体演化 斑岩铜矿 云南哈播 

分 类 号：P618.41[天文地球—矿床学] P618.65[天文地球—地质学]