黔西南晴隆锑矿床伴生金的赋存状态及其地质意义
Occurrence of associated gold in the Qinglong antimony deposit,SW Guizhou,China,its significances

杜丽娟 ^1,2 杨瑞东 ^1,2 ^* 陈军 ³ 高军波 ^1,2 郑禄林 ^1,2 张建 ^1,2

文摘	晴隆锑矿床是右江盆地的大型锑矿床之一,近些年的找矿勘探成果显示,晴隆锑矿床普遍发育有金矿化,呈Sb、Au共生的特征,但是,有关晴隆大厂锑矿中伴生Au矿化的相关科学研究尚未开展。本文通过系统的扫描电子显微镜(SEM)、电子探针(EPMA)分析和纳米二次离子质谱(Nano-SIMS)微量元素扫面分析,确定了晴隆锑矿床伴生Au的矿化类型及Au的赋存状态。结果显示,晴隆锑矿床发育辉锑矿、黄铁矿、黄铜矿和黝铜矿等硫化物,其中环带状含砷黄铁矿是主要的载金矿物,Au主要以化学结合态(Au~(1+))的方式赋存于富砷黄铁矿环带中,其矿化类型为典型的卡林型金矿化。黄铁矿核部为沉积-成岩阶段黄铁矿(Py-Ⅰ),呈贫Au、As,富S和Ti特征,环带为热液黄铁矿(Py-Ⅱ),呈富Au、As、Cu和Se,贫S特征。元素Nano-SIMS扫面(mapping)显示,热液环带中Au、Se、Cu和As具有明显的纳米级元素分带,显示出流体间歇式、脉冲式活动的特征。通过对晴隆锑矿床和邻区典型金矿床(水银洞金矿床)的成矿对比,金矿床和锑矿床具有相近的成矿时代、围岩蚀变和硫源,但成矿流体性质和演化过程明显不同,初步认为Au、Sb的这种成矿共性导致了Au-Sb-(As-Hg-Tl)在低温成矿区内普遍矿化,而流体性质的不同致使元素发生空间上的分异。
其他语种文摘	The Qinglong Sb deposit is a large-scale Sb deposit,situated within a low-temperature metallogenic belt in the Youjiang basin.In recent years,geological exploration and mining at Qinglong have revealed extensive Au mineralization,hosted by the Dachang layer.However,no detailed study has been carried out on the occurrence of gold in this newly discovered deposit at Qinglong.Therefore,this study used scanning electron microscopy(SEM),electron probe microanalysis(EPMA),and trace-element mapping of Nano-SIMS analysis to reveal the occurrence and mineralization style of associated gold in the Qinglong deposit.SEM indicates that the main sulfides include stibnite and pyrite,together with minor chalcopyrite and Fe-Sb tetrahedrite,and that zoned pyrites are the main Au-bearing minerals.The cores of zoned pyrite grains are enriched in S and Ti,but depleted of Au and As.In contrast,the rims of most zoned pyrites contain elevated Au and As contents,while S has been lost from the rims.Comparing the mineral chemistry of sulfides from different mineralization stages reveals that the As content in sulfides increases from the early-ore stage to the late-ore stage.EPMA data indicates that Au presents as Au~(1+) in the As-rich zones of pre-existing pyrite grains,which is consistent with the occurrence of Au in the Carlin-type deposit,SW Guizhou.Furthermore,comparison with a representative Carlin-type Au deposit(e.g.,Shuiyindong deposit)in the Youjiang basin revealed that the differences in ore-forming fluid,between Au deposits and the Sb deposit,is probably responsible for the paragenesis and separation between the Au and Sb mineralization process.
来源	地球化学 ,2020,49(4):368-384 【核心库】
DOI	10.19700/j.0379-1726.2020.04.002
关键词	Au的赋存状态 ; 环带状黄铁矿 ; 辉锑矿 ; 锑金矿床 ; 晴隆
地址	1. 贵州大学资源与环境工程学院, 贵州, 贵阳, 550025 2. 贵州大学, 喀斯特地质资源与环境教育部重点实验室, 贵州, 贵阳, 550025 3. 中国科学院地球化学研究所, 矿床地球化学国家重点实验室, 贵州, 贵阳, 550002
语种	中文
文献类型	研究性论文
ISSN	0379-1726
学科	地质学
基金	国家自然科学基金 ; 贵州省人才基地项目
文献收藏号	CSCD:6861997