中文摘要:对斑岩、矽卡岩及角岩矿物中石英的熔融包裹体和流体包裹体进行测温，得到甲玛铜多金属矿床斑岩体形成温度为634～887℃，斑岩体中流体开始出溶的压力为59.1 MPa。从岩浆阶段、岩浆_热液阶段、矽卡岩阶段、矽卡岩退变质阶段到石英-硫化物阶段，温度范围为170～540℃，盐度集中在15%～50%范围内，密度为0.9233～1.0805 g/cm3，成矿流体主要为NaCl-H2O体系。早期最低成矿压力为31.8 MPa，最浅成矿深度为1.1778 km。通过流体包裹体的离子成分、气相成分比值与图解、氢氧同位素数据分析，表明甲玛铜多金属矿床的成矿流体为岩浆来源，并有后期大气降水的混入。成矿流体的形成和演化经历了岩浆出溶、超临界流体的相分离、流体的减压沸腾作用及岩浆热液、挥发分与碳酸盐围岩接触带的充填/交代作用。岩浆-热液演化过程中的成矿元素，从最早的岩浆结晶分异阶段开始到岩浆期后热液阶段，都强烈地选择性进入挥发分气相中进行迁移。流体的减压沸腾、混合作用最终导致成矿元素的沉淀，甲玛矿床在成因上与斑岩-浅成低温热液成矿系统中的岩浆-热液成矿作用有关。
Abstract:A study of the homogenization temperature and characteristics of melt inclusions and fliud inclusions in the Jiama copper polymetallic deposit shows that the formation temperature of the porphyry body was 634～887℃, and the exsolution pressure of the fluids was 59.1 MPa. The temperature of five ore-forming stages was 170～540℃, the salinity concentration was 15%～50%, and the density was 0.9233～1.0805 g/cm3. The ore-forming fluids were mainly of the NaCl-H2O system. The early ore pressure was higher than 31.8 MPa, and the early mineralization occurred below 1.1778 km. The ratios and illustration diagrams of ioncompositions and gas compositions and the analyses of oxygen and hydrogen isotopes indicate that the ore-forming fluids of the Jiama copper polymetallic deposit were derived from magma, with the mixing of precipitated water in the late period. The formation and evolution of the ore-forming fluids experienced exsolution of magma, phase separation of supercritical fluid, decompression and boiling, the filling or metasomatism between magmatic hydrothermal-volatile fluids and carbonate wall rocks. The metallogenic elements selectively entered the volatile and were transported. The decompression, boiling and mixing resulted in the eventual precipitation of metallogenic elements. The ore deposit is genetically of magmatic-hydrothermal mineralization in the unified porphyry-skarn-epithermal ore-forming system.
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基金项目:本文得到“科技部行业专项协作研究”(200911007-12)、地保工程项目(1212010012005)、青藏专项(编号:1212010818089)、西藏华泰龙矿业开发有限公司勘探项目、技术开发项目“西藏墨竹工卡县甲玛铜多金属矿床地质特征及找矿方向研究”项目(编号: E0804)的
引用文本：
周云,汪雄武,唐菊兴,秦志鹏,彭惠娟,李爱国,杨科,王华,李炯,张继超.2011.西藏甲玛铜多金属矿床成矿流体来源及演化[J].矿床地质,30(2):231~248周云,汪雄武,唐菊兴,秦志鹏,彭惠娟,李爱国,杨科,王华,李炯,张继超.2011.Origin and evolution of ore-forming fluids from Jiama copper polymetallic deposit in Tibet[J].Mineral Deposits30(2):231~248
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