云南金顶铅锌矿床硫化物电子探针分析及其对矿床成因的指示

    Electron microprobe analysis of sulfide and its implication on genesis of Jinding lead zinc deposit in Yunnan Province

    • 摘要: 金顶铅锌矿床位于滇西兰坪思茅盆地北部,为世界级超大型铅锌矿床。应用电子探针分析(EPMA)技术测定了金顶铅锌矿床中不同矿段(北厂、跑马坪、白草坪)黄铁矿、闪锌矿的微量元素组成,探讨金属硫化物的地球化学特征、矿床成矿环境,从而为研究区矿床成因提供依据。结果表明,各个矿段不同寄主岩石中黄铁矿相对富集Pb、Zn、Co,贫Cu、Cd、Ni、Sb、Te等微量元素,闪锌矿相对富集Cd、Pb等微量元素,贫Fe、Mn、Ag、Cu、Sb等。微量元素Cd、Fe、Mn、Sb、Cu、Pb、Co、Zn等可能以类质同象、矿物包体及多种形式赋存于金属硫化物中。硫化物微量元素特征显示其主要形成于中低温,成矿温度自白草坪-北厂-跑马坪呈现上升特征,具盆地卤水特征。综合矿床地质特征及微量元素特征,表明金顶铅锌矿床应属于密西西比河谷型(MVT)矿床一类。

       

      Abstract: The Jinding lead-zinc deposit is located in the northern of the Lanping-Simao Basin in western Yunnan, which is a world-class super large lead-zinc deposit.The electron probe microanalysis (EPMA)technology was used to determine the trace element composition of pyrite and sphalerite in different ore sections of the Jinding lead-zinc deposit in this paper (Beichang, Paomaping and Baicaoping).This paper discusses the geochemical characteristics of metal sulfide and the metallogenic environment of the deposit, which provide a basis for the genesis of the deposit in the study area.The results show that the different host rocks in each ore section are relatively enriched in Pb, Zn and Co, but poor in trace elements, such as Cu, Cd, Ni, Sb and Te, while sphalerite is relatively enriched in Cd and Pb, but poor in trace elements, such as Fe, Mn, Ag, Cu and Sb.Trace elements, such as Cd, Fe, Mn, Ni, Sb, Cu, Pb, Co and Zn, could occur in sulfides as isomorphism, mineral inclusions or various forms.The characteristics of trace elements of sulfides show that there are mainly formed at medium and low temperature.The mineralization temperature shows rising characteristics from Baicaoping to Beichang to Paomaping, which has the characteristics of basin brine.According to the geological and trace element characteristics of the deposit, Jinding lead-zinc deposit should belong to MVT deposit.

       

    /

    返回文章
    返回