上扬子地台震旦系铅锌矿床类型及找矿方向

上扬子地台含铅锌矿地层主要为震旦系。震旦系在上扬子地台主要发育上统灯影组,次有下统陡山沱组。将上扬子地台震旦系铅锌矿床成因划分为一级为叠生矿床,二级为层控矿床,三级为热水沉积改造矿床和热水沉积再造矿床四级类型,该类型按铅锌比例进一步划分为富铅型、富锌型、铅锌共生型。研究区内最重要的铅锌矿床成因类型为南郑马元、会东大梁子铅锌矿为代表的富锌型。陕西南郑、紫阳—镇坪地区,湖北武当、神农架、黄陵地区,以及地台西缘的安宁河、甘洛—小江、峨边—寻甸等地区的震旦系是寻找铅锌矿的最有利地段。

Sinian System Pb-Zn Deposit Types and Prospecting Direction of Upper Yangtze Plateform

The dominating stratigraphy containing Pb-Zn deposits in upper Yangtze platform is the Sinian system in which the Dengying formation and the Doushantuo formation developed.Based on the genetic types of Pb-Zn deposits from the Sinian system in Yangtze platform,the Pb-Zn deposits can be classified into four types: the first is superimposed deposits,the second is strata-bound deposits,the third is hydrothermal sedimentary-transformation deposits and the fourth is hydrothermal sedimentary-reformed deposits;the four types are further divided into Pb-rich type,Zn-rich type and Pb-Zn paragenesis type by ratios of Pb to Zn.The Mayuan Pb-Zn deposit in Nanzheng,Daliangzi Pb-Zn deposit in Huidong are the representative deposits in Zn rich.The districts developed the Sinian system are the most favorable areas to explore Pb-Zn deposits: Nanzheng,Ziyang-Zhenping in Shaanxi,Wudang,Shennongjia,Huangling in Hubei and Anning river,Ganluo-Xiaojiang,Ebian-Xundian in the west edge of the platform.