四川丹巴独狼沟金矿中金与碲铋矿物的赋存状态及金的富集机制  

The occurrence state of gold and tellurium⁃bismuth minerals and enrichment mechanism of gold in Dulanggou gold deposit of Danba,Sichuan Province

作　　者：马天祺 张燕[1] 陈翠华[1] 李引 陈曦[2] 杨玉龙 刘舒月 辜鹰 赖翔 MA Tian-qi;ZHANG Yan;CHEN Cui-hua;LI Yin;CHEN Xi;YANG Yu-long;LIU Shu-yue;GU Ying;LAI Xiang(College of Geosciences,Chengdu University of Technology,Chengdu 610059,China;School of Earth Sciences and Technology,Southwest Petroleum University,Chengdu 610500,China)

机构地区：[1]成都理工大学地球科学学院,四川成都610059 [2]西南石油大学地球科学与技术学院,四川成都610500

出　　处：《岩石矿物学杂志》2023年第4期541-554,共14页Acta Petrologica et Mineralogica

基　　金：四川省科技厅面上项目(2018JY0477);四川省科技厅自然科学基金项目(2023NSFSC0274)。

摘　　要：独狼沟金矿是位于丹巴成矿带中穹窿边缘的典型的石英脉型金矿,矿床中发育大量明金与碲铋矿物。本文以独狼沟金矿中碲铋矿物及自然金为主要研究对象,通过显微岩相学观察、扫描电镜、能谱以及电子探针分析,对矿床中碲铋矿物和自然金的赋存状态进行了较为详细的研究,并对金的富集机制进行了探讨。结果表明,碲铋矿物与自然金主要在成矿Ⅱ、Ⅲ阶段产出,矿石中自然金主要为含银自然金,成色整体偏高,平均为881,碲铋矿物主要有楚碲铋矿、叶碲铋矿、赫碲铋矿、硫碲铋矿B、未命名碲铋矿物(Bi_(2)Te、Bi_(8)Te_(3)、Bi_(3)Te)以及自然铋,碲铋矿物与自然金具密切的时空关系。结合前人流体包裹体的研究结果,认为成矿Ⅱ阶段到Ⅲ阶段过渡的过程中温度以及体系中碲逸度的降低是矿床中多种碲铋矿物相形成的关键,独狼沟金矿成矿的物理化学条件以及碲铋矿物与自然金的矿物特征均指示成矿过程中金-铋-碲熔体对热液中金的抽取是导致自然金富集的关键。The Dulanggou gold deposit is a typical quartz vein type gold deposit,which is located at the edge of the dome in the Danba metallogenic belt.A large number of visible gold and tellurium⁃bismuth minerals are developed in the deposit.Taking tellurium⁃bismuth minerals and native gold in Dulanggou gold deposit as the main research object,the occurrence states of tellurium⁃bismuth minerals and native gold in the deposit were studied in detail through microscopic petrography observation,scanning electron microscope,energy dispersive spectrometer and electron probe analysis.Simultaneously,the enrichment mechanism of gold was also discussed.The results show that native gold and tellurium⁃bismuth minerals were mainly produced in theⅡandⅢmineralization stages of the Dulanggou gold deposit.The native gold in theⅡandⅢmineralization stages is mainly silver⁃bearing native gold,and the gold fineness is high with an average of 881,the main tellurium⁃bismuth minerals are tsumoite,pilsenite,hedleyite,joseite B,unnamed tellurium⁃bismuth minerals(Bi_(2)Te、Bi_(8)Te_(3)、Bi_(3)Te)and native bismuth.These tellurium⁃bismuth minerals have a close relationship with native gold in time and space.Combined with previous studies on fluid inclusions,it is suggested that the decrease of temperature and tellurium fugacity in the system from mineralization stageⅡto stageⅢare the important reasons for the formation of various tellurium⁃bismuth minerals.The physical and chemical conditions of the mineralization of the Dulanggou gold deposit,as well as the mineral characteristics of tellurium⁃bismuth minerals and native gold,indicate that the extraction of gold from the hydrother⁃mal solution by the gold⁃bismuth⁃tellurium melt during the mineralization process is the key to the enrichment of native gold in the mineralization process.

关 键 词：独狼沟金矿 碲铋矿物 富集机制 矿物特征 四川丹巴 

分 类 号：P618.51[天文地球—矿床学] P611[天文地球—地质学]