The Dibaonamugang Cu (Au) deposit is a newly found large deposit.Metallogenic process is divided into K-feldspar-sulfide,quartz-polymetal sulfide,carbonate-pyrite and oxidation stages.The quartz-polymetal sulfide,carbonate-pyrite stages are the main ore stage.In order to make clear the oreforming fluid characteristics and make sure the ore genesis samples are collected from deep carbonate vein (generally pyrite,chalcopyrite-bearing quartz vein of the carbonate-pyrite stage) to observe petrography and measure temperature of fluid inclusion under microscope.The results show that fluid inclusions can be classified into three types of liquid-rich inclusions,gas-rich inclusions and sub-mineral-bearing inclusions;The homogenization temperatures and salinities(w(NaCl,eq))of liquid-rich inclusions are range from 80℃ to 600℃,and 4.48％ to 18.79％,and the homogenization temperatures and salinities(w(NaCl,eq))of gas-rich inclusions are 240℃ to 560℃,5.09％ to 9.73％,and 240℃ to 560℃,36％ to 72％ of mineral-bearing inclusions.Comprehensive analysis indicates that the metallogenic fluid of Dibaonamugang was strongly boiled and boiling is the important metallogenic mechanism.The above inclusion characteristics can be correlated with those of porphyry deposits abroad thus Dibaonamugang Cu (Au) deposit should be a porphyry deposit.%地堡那木岗铜(金)矿床位于西藏多龙矿集区,探明储量达大型规模;矿床的成矿过程分为岩浆作用阶段、钾长石-硫化物阶段、石英-多金属硫化物阶段、碳酸盐-黄铁矿阶段和氧化作用阶段,其中石英-多金属硫化物阶段和碳酸盐-黄铁矿阶段为主要成矿阶段;为查明成矿流体特征,确定矿床成因类型,对取自深部矿石中的碳酸盐脉(均为碳酸盐-黄铁矿成矿阶段含黄铁矿黄铜矿石英脉)开展流体包裹体的岩相学观察和显微测温分析.分析结果表明,上述矿物中主要发育富液相、富气相和含子矿物三相包裹体.其中,富液相包裹体的均一温度与盐度分别为:t=80～600℃、w(NaCl,eq) =4.48％～18.79％;富气相包裹体的均一温度和盐度分别为:t=240～560℃、w(NaCl,eq)=5.09％～9.73％;含子矿物三相包裹体的均一温度与盐度分别为:t=240～560℃、w(NaCl,eq)=36％～72％.综合分析认为,地堡那木岗铜(金)矿床成矿流体发生了强烈的沸腾作用,流体沸腾作用是该矿床的重要成矿机制.通过与国内外典型斑岩型矿床与高硫化型浅成低温热液矿床的流体包裹体特征进行对比,其与斑岩型矿床的中高温、高盐度流体特征相似.因此,推测地堡那木岗矿床的成因类型为斑岩型铜(金)矿床.
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