安徽铜陵胡村南铜钼矿床地质和流体地球化学

发布时间：2018-05-31 22:24

  本文选题：流体包裹体 + 矿床地质　； 参考：《中国地质大学(北京)》2015年硕士论文

【摘要】：胡村南铜钼矿床是在安徽铜陵铜(金)矿集区中发现的第一个矽卡岩-斑岩复合型铜钼矿床,在长江中下游成矿带具有特殊性和典型性。本文对该矿床进行了矿床地质和成矿流体地球化学研究,旨在查明该矿床的流体成矿过程。胡村南铜钼矿床流体成矿过程可以划分为高温气成热液期、中高温热液期和低温热液期三个成矿期。高温气成热液期发育钾长石化和矽卡岩化,中高温热液期发育绿泥石化、绿帘石化和绢云母化,而低温热液期主要发育碳酸盐化。其中中高温热液期为主要矿化期,形成辉钼矿和黄铜矿等多种硫化物网脉。高温气成热液期矿物中发育富液相和含子晶多相包裹体,中高温热液期矿物中也主要发育富液相包裹体和含子晶多相包裹体,但可见少量的富气相包裹体,低温热液期矿物中只发育富液相包裹体。从高温气成热液期经中高温热液期到低温热液期,成矿流体均一温度从435℃以上经203~458℃降低到156~276℃,盐度从14.0%~64.9%Na Cleq经4.6%~47.5%Na Cleq降低到1.0%~15.5%Na Cleq。从早期到晚期,成矿流体从高温、高压、高盐度流体向低温、低压、低盐度流体演化。矿化主要发生在中高温热液期石英-辉钼矿阶段和石英-黄铜矿阶段,成矿深度为0.6~1.5km。氢氧同位素分析表明,中高温热液期各成矿阶段成矿流体均为岩浆水,到低温热液期碳酸盐阶段有大气降水混入。碳氧同位素反映碳可能主要来自壳幔混源岩浆,并有海相碳酸盐溶解成分的加入。地质和地球化学综合分析表明,成矿流体在演化过程中发生过不混溶作用、沸腾作用和混合作用。不混溶作用发生在气成热液期,使成矿流体中的成矿元素大量富集。沸腾作用发生在中高温热液期,导致成矿流体中的成矿元素卸载而沉淀出大量金属硫化物。混合作用主要发生在低温热液期,使流体的温度和盐度进一步降低。
[Abstract]:Hucuonnan copper and molybdenum deposit is the first skarn porphyry compound copper molybdenum deposit found in Tongling copper (gold) concentration area of Anhui Province. It is special and typical in the middle and lower reaches of the Yangtze River metallogenic belt. In this paper, ore deposit geology and ore-forming fluid geochemistry are studied in order to find out the fluid metallogenic process of the deposit. The fluid metallogenic process of Hucuonnan Cu-Mo deposit can be divided into three stages: high temperature gas hydrothermal stage, middle high temperature hydrothermal period and low temperature hydrothermal stage. Potassium feldspar and skarn were developed in high temperature gas forming hydrothermal period, green mud petrification, green curtain petrification and sericite in middle high temperature hydrothermal period, and carbonation in low temperature hydrothermal period. The high temperature hydrothermal stage is the main mineralization stage, forming various sulphide net veins such as molybdenum and chalcopyrite. There are rich liquid phase inclusions and sub-crystalline polyphase inclusions in the minerals of high temperature gas-forming hydrothermal period, and liquid rich inclusions and sub-crystalline polyphase inclusions are mainly developed in the middle and high temperature hydrothermal period minerals, but a small amount of gas-rich inclusions are found in the minerals. Only liquid-rich inclusions are developed in the minerals during the low temperature hydrothermal period. The homogenization temperature of the ore-forming fluid decreased from 435 鈩，

本文编号：1961538