湖南柿竹园钨锡钼铋多金属矿床含矿云英岩脉的流体包裹体研究  

Fluid inclusion study of the ore-bearing stockwork greisen at Shizhuyuan W-Sn-Mo-Bi deposit,Hunan

作　　者：王璐璐 倪培[1] 戴宝章[1] 李文生 潘君屹 崔健铭 高严 Wang Lulu;Ni Pei;Dai Baozhang;Li Wensheng;Pan Junyi;Cui Jianming;Gao Yan(State Key Laboratory for Mineral Deposits Research,Institute of Geo-Fluids,School of Earth Sciences and Engineering,Nanjng University,Nanjing,210023,China)

机构地区：[1]内生金属矿床成因机制研究国家重点实验室,地质流体研究所,南京大学地球科学与工程学院,南京210023

出　　处：《南京大学学报（自然科学版）》2020年第5期653-665,共13页Journal of Nanjing University（Natural Science）

基　　金：国家自然科学基金(41830426)。

摘　　要：柿竹园是南岭成矿带中著名的钨锡钼铋多金属矿床.对柿竹园矿床主成矿期云英岩脉中的黑钨矿、白钨矿、石英和晚期萤石开展了流体包裹体研究.包裹体显微测温研究表明,黑钨矿和白钨矿中只识别出富液相H2O-NaCl型包裹体,均一温度分别集中于350~400℃和250~300℃.与白钨矿相比,黑钨矿中包裹体均一温度较高,推测黑钨矿的形成可能早于白钨矿,与前人观察到白钨矿交代早期黑钨矿的结果一致.黑钨矿共生石英中发育不混溶流体包裹体组合,且均一温度较低,主要集中在300~350℃,表明石英与共生黑钨矿经历不同的流体演化过程和形成条件.白钨矿共生石英中发育与白钨矿中相似的包裹体,也为富液相H2O-NaCl型包裹体,均一温度集中在250~300℃,盐度主要为6 wt.%~8 wt.%NaCl equiv.晚期萤石中为富液相H2O-NaCl型包裹体,均一温度集中于250~300℃,盐度2.6 wt.%~9.2 wt.%NaCl equiv,记录了成矿后期的流体活动.激光拉曼探针分析表明石英中的包裹体中气相仅含有少量CO2和CH4,在柿竹园矿床的形成过程中,CO2对钨迁移和沉淀的作用可能极其有限.The world′s renowned Shizhuyuan W-Sn-Mo-Bi deposit is one of the important polymetallic deposits in the Nanling metallogenic belt. In this paper,we carried out fluid inclusion studies on the wolframite,scheelite,quartz and late fluorite from the stockwork greisen at Shizhuyuan,which is the main ore-forming stage. Detailed microthermometry indicates that both wolframite and scheelite-hosted fluid inclusions are merely H2O-NaCl type whose homogenization temperatures centralize between 350~400 ℃ and 250~300 ℃,respectively. Compared with scheelite,the homogenization temperature of wolframite is higher,which indicates wolframite might precipitate earlier than scheelite. It is concordant with predecessors′observation that early wolframite was replaced by scheelite. There are immiscible fluid inclusion assemblages in quartz that coexists with wolframite,and the homogenization tempertures of fluid inclusions in it are slightly low mainly in range of 300~350 ℃,which shows wolframite and coexisting quartz experienced different fluid evolution and formation conditions. Fluid inclusions in quartz coexisting with scheelite are similar to those in scheelite,both liquid-rich H2O-NaCl type. The homogenization temperature of the former is mainly between 250 ℃ and 300 ℃ and their salinity is centering at 6 wt.% ~8 wt.% NaCl equiv. Fluid inclusions in late fluorite are liquid-rich H2O-NaCl type with homogenization temperature between 250 ℃ and 300 ℃ and salinity among 2.6 wt.% to 9.2 wt.% NaCl equiv,recording a post-ore stage fluid activity at Shizhuyuan. The major gas components in fluid inclusions in quartz are minor CO2 and CH4,as supported by laser Raman analysis. It is suggested that CO2 may have very limited influence on the transport and formation of W-minerals in the Shizhuyuan deposit.

关 键 词：柿竹园 黑钨矿 白钨矿 流体包裹体 显微测温 激光拉曼 

分 类 号：P618.6[天文地球—矿床学]