金顶超大型铅锌矿床成矿条件分析

通过对金顶铅锌矿床矿区的区域地质背景、盆地性质以及矿区地质特征的研究,分析了该矿床 的成矿条件,认为正是由于在动荡的区域地质背景和巨厚的碎屑岩建造中,在有机质以及蒸发岩中的硫 酸岩提供还原硫的环境下,断裂系统长期继承性的活动,使得成矿热液能够稳定地向同一空间部位迁 移,并且景星组顶板和云龙组上段的底板均为以泥岩为主的细碎屑岩,从而形成圈闭,使得成矿物质淀 积下来,形成超大型矿床。金顶铅锌矿床有可能是以沉积岩为主岩的一种新型矿床。

Formation conditions of Jinding giant lead-zinc deposit

The Jinding Pb-Zn deposit is the largest Pb-Zn deposit at present in China. Its ore-forming process has been stud- ied for more than twenty years, but there are still many debates. Although the Jinding lead-zinc deposit is the sedimentary rock-hosted one,its origin is different from the other sedimentary rock-hosted Pb-Zn deposit type, such as MVT, Sedex and SST. By studying the regional geological setting, basin nature and geologic characteristic of the ore field, this paper believes that firstly, the formation of the Jinding Pb-Zn deposit was under the conditions of the unstable regional geological setting and very thick clastic formation; secondly, organic materials and sulphates provided the necessary reducing sulphur; thirdly, the elongate activity of faults made ore fluids stably migrate to the same space; and lastly, the rocks on the Jinxing formation and under the upper part of the Yunlong Formation could have formed the traps suitable to the precipitation of metals and re- sulted in the formation of the giant Pb-Zn deposit.