南秦岭新发现王庄金矿床矿物成分及其地质意义
Material Composition and Geological Significance of the Newly Discovered Wangzhuang Gold Deposit in South Qinling
孟五一 1张振 1高永宝 1魏立勇 1贾彬 1郑鑫 1刘宁波1
作者信息
- 1. 中国地质调查局西安矿产资源调查中心,陕西 西安 710199
- 折叠
摘要
王庄金矿是 2021年南秦岭地区找矿新发现的矿床,矿床类型为微细浸染型,矿体受构造和地层双重控制,呈层间破碎带产出.王庄金矿床矿石矿物主要为毒砂、黄铁矿,通过镜下鉴定及电子探针分析,金主要以不可见金存于毒砂、含砷黄铁矿中,未见自然金.结合野外工作,根据矿物共生组合及其交生关系可将王庄金矿床划分为 4个成矿阶段:Ⅰ.黄铁矿、石英脉成矿早阶段;Ⅱ.毒砂、黄铁矿、石英脉成矿主阶段;Ⅲ.石英脉伴少量多金属硫化物阶段;Ⅳ.碳酸盐岩晚阶段.不同阶段的黄铁矿具有不同的微量元素特征:Ⅰ阶段黄铁矿贫As、Au,富Fe、S;Ⅱ、Ⅲ阶段黄铁矿具高As、Au,低S、Fe特征,且此阶段黄铁矿当中Au、As存在一定的正相关关系.王庄金矿矿石中黄铁矿Co/Ni均值为 2.03,中位数为 1.34,指示成矿主阶段形成的黄铁矿有岩浆流体的加入.且在Co/Ni<1及 1.2<Co/Ni<2.5范围内存在两个含金集中区,表明可能存在两种不同流体的成矿作用.综合矿床地质及矿物组构特征初步认为,王庄金矿床存在多阶段的成矿作用.
Abstract
The Wangzhuang gold deposit is a newly discovered deposit in South Qinling in 2021.The ore type is a fine disseminated type.The ore body is controlled by both structure and stratum,and it is produced in an in-terlayer fracture zone.The main metallic minerals of the Wangzhuang gold deposit are arsenopyrite and pyrite,According to microscopic identification and electron probe analysis,the gold is mainly invisible gold in ar-senopyrite and arsenian pyrite,and no natural gold is found.Based on the field work,the Wangzhuang gold de-posit can be divided into four ore-forming stages:Ⅰ,the early ore-forming-stage of pyrite quartz veins;Ⅱ,the main stage of arsenopyrite,pyrite,and quartz veins;Ⅲ,quartz veins with a small amount of polymetallic sulfide stage;Ⅳ,late carbonate stage.The pyrite in different stages has different characteristics of trace elements:stage Ⅰ pyrite is poor in As and Au,rich in Fe and S;the pyrite of stage Ⅱ and Ⅲ are characterized by high As,Au,low S and Fe,and there is a positive correlation between Au and As in pyrite of this stage.The average Co/Ni ratio of pyrite in the Wangzhuang gold deposit is 2.03 and the median is 1.34,indicating that pyrite formed in the ore-forming master stage has the addition of magmatic fluid.In addition,there are two gold-bearing areas in the range of Co/Ni<1 and 1.2<Co/Ni<2.5,indicating that there may be mineralization of two different fluids.Based on the geological and mineral fabric characteristics of the deposit,it is preliminarily concluded that there is multi-stage mineralization in the Wangzhuang gold deposit.
关键词
王庄金矿/物质组成/黄铁矿/南秦岭Key words
the Wangzhuang gold deposit/material composition/pyrite/the South Qinling引用本文复制引用
基金项目
陕西省自然科学基础研究计划项目(2023-JC-QN-0363)
中国地质调查局项目(DD20230370)
&&(DD20230057)
&&(DD20230060)
出版年
2024
国家科技期刊平台
NSTL
万方数据