非硫化物型锌-铅矿床研究现状及其进展

Research Status and Progress of Nonsulfide Zinc-Lead Deposit

非硫化物型锌-铅矿床主要由一系列锌、铅"氧化物"组成。非硫化物型锌-铅矿床可以分为表生和深成2种类型。表生非硫化物矿床的形成主要与表生的氧化作用有关,主要含有菱锌矿、异极矿、白铅矿等;根据成矿方式的不同分为直接交代型、围岩交代型、残余-岩溶充填型。深成非硫化物矿床的形成主要与热液流体的有关,主要含有硅锌矿、菱锌矿、白铅矿等;根据形成的不同方式被分为构造控制型矿床与层状矿床。深成矿床显示与表生矿床不同的C-O同位素特点。笔者主要讨论非硫化物型铅锌矿床的特征及成因机制,并介绍中国火烧云锌-铅矿床的研究进展。火烧云铅锌矿已探明锌-铅金属资源量大于1 700万t,已成为中国新的最大铅锌矿。矿床成矿矿物以菱锌矿、白铅矿、方铅矿与闪锌矿为主,最新研究结果表明矿床主要经历2期成矿作用:早期的铅锌碳酸盐阶段(主要)与晚期的铅锌硫化物阶段。其矿床地质特征及稳定同位素特征显示火烧云铅锌矿床为深成层状(喷流)的非硫化物型锌-铅矿床。

The nonsulfide zinc-lead deposits are composed of zinc and lead ＂oxides＂.Nonsulfide zinc-lead deposits are classified as supergene and hypogene deposits.The supergene deposits are primarily formed by the supergene oxidation,which are mainly composed of smithsonite,hemimorphite and cerussite.These supergene nonsulfide deposits consist of three subtypes,as as direct-replacement deposits,wall-rock replacement deposit,and residual and karst-fill deposit.Thehypogene deposits are mainly formed by the hydrothermal solutions which consist dominantly of willemite,smithsonite and cerussite.These hypogene deposits are subdivided into structurally controlled deposit and stratiform deposit.The hypogene deposits show distinct carbon and oxygen compositions with the supergene deposits.In this paper,the characteristics and genesis of the nonsulfide deposits have been presented,and the research progress on the Huoshaoyun zinclead deposit has been introduced.The Huoshaoyun deposit is the largest zinc-lead deposit in China,with the zinc-ead metal reserve of more than 17 million tonnes.This deposit is primarily composed of smithsonite,cerussite,galena and sphalerite.The latest research show that this deposit was experienced two ore-forming stages：an early and primary zinc-lead carbonate ore-forming stage,and a late zinc-lead sulfide ore-forming stage.The geological characteristics and stable isotope features indicate that the Huoshaoyun deposit is a stratiform（exhalative）hypogene nonsulfide zinc-lead deposit.