贵州水银洞卡林型金矿床金的赋存状态初步研究  

THE OCCURRENCE OF GOLD AT SHUIYINDONG CARLIN-TYPE GOLD DEPOSIT,GUIZHOU

作　　者：张弘弢[1] 苏文超[1] 田建吉[1] 刘玉平[1] 刘建中 刘川勤 

机构地区：[1]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 [2]贵州紫金矿业股份有限公司,贵州贞丰562200

出　　处：《矿物学报》2008年第1期17-24,共8页Acta Mineralogica Sinica

基　　金：贵州省科学技术基金(批准号:2100);国家自然科学基金(批准号:40672067);中国科学院知识创新工程项目(KZCX3-SW-125)

摘　　要：采用电子探针背散射电子图像、波谱和能谱分析技术，对贵州水银洞卡林型金矿床原生富矿石中的含砷黄铁矿Au、As等元素含量及其分布规律进行了系统研究。结果发现有两种金的赋存形式：①不可见金，主要赋存在含砷黄铁矿之中，Au与As之间呈楔形分布关系，推测金以化学结合态金（Au^＋）的形式进入含砷黄铁矿的结构；②显微-次显微自然金颗粒（0．1～6μm），分布在含砷黄铁矿的边缘。提出含金-砷黄铁矿的形成可能与含Au热液-岩石相互作用过程中含Fe碳酸盐矿物溶解释放Fe有关，含Fe碳酸盐赋矿围岩是形成高品位、大型卡林型金矿床最重要的控制因素之一，与去碳酸盐化有关的碳酸盐脉可能是寻找深部隐伏卡林型金矿体的重要标志。In this study, an electron microprobe analyzer （EMPA） was used to map the spatial distribution of ＂invisible＂ gold and submicron to micron size visible gold particles in arsenian pyrite in a high grade ore sample from the Shuiyindong Carlin-type gold deposit, Guizhou, China. The samples studied were hosted in Permian bioclastic ferroan limestone of the Longtan Formation and showed evidence of decarbonation, silicification and sulfidation and was deposited in two stages. The results showed that there are two occurrences of gold in arsenian pyrite. One is invisible gold in arsenian pyrite with detectable Au （ 〉 400 to 3800 ppm） and the other is comprised of sub-micrometer to micron size （0. 1 -6 μm） gold particles that are occasionally present in the gold-bearing arsenian pyrite edges. The results also showed that As and Au contents of arsenian pyrite plot in a wedge-shaped zone. On the basis of petrography data of the ore, nism of gold deposition in Carlin-type system. Finally, we proposed that the Fe-poor calcite and dolomite veins or veinlets associated with mineralization may be an effective pathfinder for exploration of nearby unexposed Carlin-type gold mineralization.

关 键 词：金的赋存状态 成矿过程 卡林型金矿 水银洞 贵州 

分 类 号：P578.1[天文地球—矿物学] P618.5[天文地球—地质学]