最近几年,随着危机矿山深部找矿工作的深入,中国铅锌矿床找矿工作取得了较大进展,这不仅归功于深部钻探工作的开展,也得益于找矿理论的不断深化。总结过去几十年的找矿勘查经验,人们开始意识到地质-地球化学界面对找矿的指导作用。基于此,Si/Ca界面控矿逐渐被人们应用于铅锌找矿工作当中。文章通过对国内外一些代表性矿床的对比分析,认为不同成因的矿床都可具有同一种控矿因素———Si/Ca界面。Si/Ca界面控矿既是不同类型岩石物理性质界面,又具有地球化学意义。文章划分出侵入接触界面、火山沉积接触界面和沉积接触界面3种不同的Si/Ca界面组合方式,并分别举实例说明Si/Ca界面组合对铅锌矿体定位的控制作用;从成矿元素地球化学特性、Si/Ca界面构成异相定位空间和提供地球化学障等角度,分析了Si/Ca界面的控矿机制,界面控矿有望在找矿勘查过程中起到指导作用。
The geneses and ore control are always the important aspects in the study of Pb-Zn deposits.There are different metallotectonitic condidtions for different genetic type deposits.Statistics show that the interface between silica and calcareous bed is an important ore-control factor for every types of Pb-Zn deposits.This conclusion was reached on the basis of summing up a lot of classic Pb-Zn deposits in China.The interface between silica and calcareous bed is the boundary not only of rock geophysics but also of geochemistry.Three different combined types of interfaces are distinguished.They are interface between intrusion and host rock,volcanic rock and sedimentary rock,different sedimentary rocks.For each type of interface,there are examples showing the control action on the ore body.Obviously,the interface between silica and calcareous bed has an important guiding significance for ore prospecting.