辽宁白云金矿床围岩蚀变作用及其与金的成矿关系  

Wall Rock Alteration and Its Metallogenic Relationship with Gold of Baiyun Gold Deposit in Liaodong Peninsula,North China Craton

作　　者：张志超 王玉往[1] 李德东[1] 王伟 邱金柱 李生辉 Zhang Zhichao;Wang Yuwang;Li Dedong;Wang Wei;Qiu Jinzhu;Li Shenghui(Deep Exploration Technical Center for Non-Ferrous Mines,Beijing Institute of Geology and Mineral Resources,Beijing 100012,China;2103 Branch of Non-Ferrous Geological Bureau of Liaoning Province,Dandong 118008,China)

机构地区：[1]北京矿产地质研究院有色金属矿山深部资源勘查工程技术研究中心,北京100012 [2]辽宁有色地质局一〇三队,辽宁丹东118008

出　　处：《地球科学》2020年第11期3900-3912,共13页Earth Science

基　　金：深地资源勘查开采项目(No.2018YFC0603804)。

摘　　要：为了理清白云矿床硅钾蚀变与金沉淀的成因关系,对硅钾蚀变岩石和未蚀变的矽线石云母片岩进行主微量元素测试分析,同时选取蚀变岩型和石英脉型矿石中黄铁矿进行电子探针分析.以Al2O3作为不活动组分,通过质量平衡计算,发现明显带入的组分为CaO、K2O、Na2O、SiO2、Ag、As、Co、Cu、Ni,迁出组分为FeO、Cr、Zn.蚀变岩型和石英脉型矿石中黄铁矿均表现出亏S和富Fe的特征,二者的Au/Ag值都大于0.5,Fe/(S+As)值变化范围为0.857~0.896.两种矿石中黄铁矿均为热液型,形成于中浅成的中温环境.在硅钾蚀变过程中,热液中的含硫组分损失,还原硫活度降低破坏了金-硫络合物的稳定性,导致Au的沉淀.In order to clarify the genetic relationship between gold precipitation and silicic,K-feldspar alterations,silicic-potassicaltered and unaltered sillimanite/mica schist were selected for major and trace element analyses,while pyrites from quartz vein type and altered-rock type ore were selected for electron microprobe analyses.With Al2 O3 chosen as inactive components,the mass balance calculations show that CaO,K2 O,Na2 O,SiO2,Ag,As,Co,Cu and Ni are brought in,contrary to FeO,Cr and Zn.Pyrites from altered-rock type ore and quartz vein type ore show the characteristics of depleted S and enriched Fe.The value of Au/Ag of pyrites is greater than 0.5,and the value of Fe/(S+As)ranges from 0.857 to 0.896.Pyrites are of hydrothermal origin and have formed in the medium-shallow depth and medium temperature environment.During the process of silicic and Kfeldspar alterations,sulfur components are lost from hydrotherm.The decrease of sulfur activity destroys the stability of the goldsulfur complex and leads to gold precipitation.

关 键 词：围岩蚀变 质量平衡 金的沉淀 白云金矿床 辽东地区 矿床学 

分 类 号：P614[天文地球—矿床学]