摘要
青山铅锌矿床是黔西北铅锌矿集区威宁-水城成矿亚带上产于蚀变结晶灰岩中的典型矿床。基于系统的野外地质调研和大比例尺矿化-蚀变剖面测量,通过矿区赋矿围岩的岩石学和矿石学及微量元素地球化学研究,以揭示矿床的形成过程和成因,构建了该矿床地球化学分带模式,进而指导矿区深边部勘探工作。研究表明:①矿区赋矿围岩为石炭系马平组(C 2 m)灰岩,并非白云岩,是川滇黔铅锌多金属成矿区内少见的;②围岩蚀变明显,自矿体中心向外侧依次呈现出强重结晶灰岩带、弱重结晶灰岩带及未重结晶灰岩带的分带规律。③微量元素迁移规律显著,从未结晶灰岩经蚀变灰岩到矿石,亲硫元素(如Zn、Pb、As、Cd、Ga、Sb、Ag等)大量迁入,而亲铁元素(如V、Cr、Mo等)少量迁入,元素Sr不断迁出,元素Ba由迁入状态变为迁出状态;④矿床中蚀变灰岩由未结晶灰岩重结晶而成,成矿过程中有相对富含稀土元素的热液加入,矿床形成于氧逸度较高、温度较低的环境。
Qingshan Pb-Zn deposit is a typical deposit hosted in altered crystalline limestone in the Weining-Shuicheng metallogenic sub-belt in the Pb-Zn ore concentration area of Northwest Guizhou.Through systematic field work and large-scale alteration mineralization profile survey,the petrologic characteristics,ore mineralogy and trace element geochemical characteristics of surrounding rocks in the mining area,the formation process and genesis of the deposit is studied,the geochemical zonation model of the deposit is constructed to guide the exploration work in the deep and marginal parts of the mining area.The study result is shown as follows.(1)The ore-hosted rock of the deposit is Carboniferous Maping formation(C 2 m)limestone,not dolomite,which is rare in Sichuan-Yunnan-Guizhou Pb-Zn polymetallic metallogenic area.(2)The alteration of the surrounding rock is obvious.From the center of the ore body to the outside,there is a zonation regularity of strong recrystallized limestone belt,weak recrystallized limestone belt,and unrecrystallized limestone belt.The migration regularity of trace elements is obvious.From uncrystallized limestone,altered limestone to ore,sulfophile elements,such as Zn,Pb,As,Cd,Ga,Sb,Ag,etc.,immigrate in a large amount,while siderophile elements,such as V,Cr,Mo,etc.,immigrate in a small amount.Element Sr is constantly emigrated,and element Ba changes from immigration state to emigration state.(4)The altered limestone in the deposit is formed by recrystallization of uncrystallized limestone,there is the hydrothermal solution rich in rare earth elements in the ore-forming process,and the deposit is formed in the environment of high oxygen fugacity and low temperature.
作者
周威
陈进
韩润生
王明志
宋丹辉
ZHOU Wei;CHEN Jin;HAN Runsheng;WANG Mingzhi;SONG Danhui(Faculty of Land Resources Engineering,Kunming University of Science and Technology,Kunming 650093,Yunnan,China;Southwest Institute of Geological Survey,Geological Survey Center for Nonferrous Metals Resources,Kunming 650093,Yunnan,China;Yunnan Chihong Zinc and Germanium Co.,Ltd.,Qujing 650224,Yunnan,China)
出处
《矿产与地质》
2021年第2期222-236,共15页
Mineral Resources and Geology
基金
国家自然科学基金项目(41572060)
云岭学者资助项目(2014)
云南省矿产资源预测评价工程实验室(2012)
云南省高校和昆明理工大学成矿动力学与隐伏矿预测创新团队项目共同资助。
关键词
赋矿结晶灰岩
地球化学特征
铅锌矿床
黔西北青山
ore-hosted crystalline limestone
geochemical characteristics
lead-zinc deposit
Qingshan in Northwest Guizhou
