扎西康铅锌锑多金属矿已发现规模较大的四个矿体,控制资源量达100万吨以上.矿体均分布在NNW或NNE张扭性断裂破碎带内,受断裂破碎带控制,矿体与围岩界线明显.铅同位素位组成显示成矿物质主要来源于上地壳,包裹体研究成矿流体为中低温-低盐度成矿,氢、氧、硅同位素组成显示成矿流体主要为大气降水下渗循环构成的地热水.硫同位素特征显示硫源主要来源于围岩中的海相地层还原硫.He- Ar同位素组成表明成矿流体主要为地壳流体和饱和大气水的混合,没有明显的地幔流体成分混入.矿床成因属于沉积-构造-地下热水改造的多阶段充填交代中低温热液脉状矿床.%There are four large scale existing ore-bodies in the Zhaxikang Pb-Zn -Sb polymetallic deposit. The controlled metal reserves are more than one million tones. The ore-bodies are located in NNW or NNE trending extension-shear fault and fracture belts. The border between the ore-body and wall rock is clear. Lead isotopic composition indicates that ore material is mainly from the upper crust. Inclusion research result shows that mineral fluid is of middle temperature with middle and low salt degree. Hydrogen, oxygen and silicon isotopic composition indicate that the mineral fluid is mainly of terrestrial heat water of atmosphere precipitation oozing and circling. Sulfur isotopic feature shows that sulfur is mainly from deoxidized sulfur of marine stratum of wall rock. He-Ar isotopic composition indicates that the mineral fluid is mainly the mixture of crust fluid and saturated atmosphere water, with less mantle fluid composition. It is proposed that the genesis of the Zhaxikang Pb-Zn-Sb polymetallic deposit belongs to a tipical type of hydrothermal vein deposit of low and middle temperature with many stages of infilling and replacement of sedimentation-struc-ture-undergroud hot water reconstructing.
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