河南灵宝市樊岔金矿成矿流体研究

发布时间：2018-05-27 19:54

  本文选题：石英脉型金矿 + 矿床地质　； 参考：《中国地质大学(北京)》2017年硕士论文

【摘要】：樊岔金矿是小秦岭金矿集区中的一个典型的石英脉型金矿,成矿流体是石英脉型金矿形成的关键控制因素之一,也是矿床学研究的重点内容。本文对该矿床开展了详细的矿床地质特征和流体包裹体研究,揭示了流体的来源与演化,并在此基础上探讨了矿床成因。野外调研和室内观察结果表明,樊岔金矿赋矿围岩主要为太华群斜长角闪片麻岩;矿体受脆性断裂控制;围岩蚀变主要为硅化、钾长石化、绢云母化、黄铁矿化和碳酸盐化。据矿物组合和脉体穿插关系将该矿成矿过程划分为五个阶段:石英钾长石化阶段(Ⅰ)、石英粗粒黄铁矿阶段(Ⅱ)、石英细粒黄铁矿阶段(Ⅲ)、石英多金属硫化物阶段(Ⅳ)和碳酸盐阶段(Ⅴ)。主成矿阶段为石英细粒黄铁矿阶段(Ⅲ)和石英多金属硫化物阶段(Ⅳ)。岩相学观察显示,该矿床流体包裹体主要相态类型为富CO2三相型、含CO2三相型和气液两相型。显微测温数据显示:从石英粗粒黄铁矿阶段到碳酸盐阶段,均一温度峰值依次为363.3℃、325.5℃、273℃、258.6℃,总体呈逐渐降低的趋势;盐度峰值依次为14.53、9.59、11.61、8.03 wt%NaCl.equiv.,略有起伏但变化不大,总体呈降低趋势。矿床成矿流体属于中低温中低盐度CO2-H2O-NaCl-(±CH4)成矿流体系统。氢氧同位素分析结果表明,成矿流体早阶段主要为变质流体,主成矿阶段主要为变质水和大气降水组成的混合流体,晚阶段以大气降水为主;流体包裹体微观特征及测温数据表明流体在主成矿阶段发生过明显的流体混合和流体不混溶作用。流体混合和流体不混溶是导致樊岔金矿金元素沉淀的主要成矿机制。
[Abstract]:Fancha gold deposit is a typical quartz vein type gold deposit in Xiaoqinling gold concentration area. The ore-forming fluid is one of the key controlling factors for the formation of quartz vein type gold deposit, and is also the key content of ore deposit study. In this paper, the geological characteristics and fluid inclusions of the deposit are studied in detail, the origin and evolution of the fluid are revealed, and the genesis of the deposit is discussed. The results of field investigation and indoor observation show that the host rock of Fancha gold deposit is mainly obliquity diorite of Taihua group, the orebody is controlled by brittle fracture, and the alteration of surrounding rock is mainly silicification, kalitization, sericite, pyrite and carbonization. According to mineral assemblage and vein intercalation relationship, the ore-forming process of this ore can be divided into five stages: quartz and potassium feldspar stage (鈪，

本文编号：1943541