中国东部前寒武纪铅锌矿床的分布及类型特征

Distribution, Types and Characteristics of the Precambrian Lead-Zinc Deposits in Eastern China

中国东部前寒武纪铅锌矿资源分布广泛,目前已探明储量的前寒武纪铅锌矿床有 51 处,其中超大型矿床1处,特大型矿床3处,大型矿床7处,中型矿床12处,其余为小型。这类矿床主要形成于中新元古代的裂谷系和裂谷系边缘的不同地质构造单元,其分布受构造控制,集中分布于华北陆块北缘东、中、西段元古宙裂谷系和扬子陆块西侧康滇地轴震旦系裂谷带东侧的边缘活动带,并以华北陆块北缘为主;成矿作用总体受火山-沉积-变质作用控制,具层控性;成矿时代有从北向南变新的趋势。根据矿床围岩的不同,可把矿床主要分为VHMS、Sedex、MVT三大类型,其中以Sedex型最为重要,规模也最大。

The Precambrian Lead-Zinc deposits are widely distributed in eastern China. 51 Precambrian deposits have been explored in the eastern China, in which there are 1 supper large scale, 3 giant large scale, 7 large scale, 12 medium scale deposits, others are small scale ones. They mainly formed in the different stratigraphic sequences of Meso- to Neo-Proterozoic rifting system. And their distribution is controlled by the different structures. The deposits are mostly concentrated in the eastern, middle and western part of the Proterozoic rifting system developed in the northern margin of North China platform, and the east-side external mobile belt of Kangdian Sinian rifting zone in the western part of Yangtz platform, all of which comprise two main ore-forming areas (or zones) of Lead-Zinc deposits, especially in the northern margin of the North China platform. The ore formation is affected by the volcanic-sedimentary-metamorphic process, and the ore-forming era has a trend of turning new from the north to the south. The deposits are of stratabound characters. According to their different country rocks, they can be divided into three types, i.e.VHMS, MVT and Sedex , in which the Sedex type is the most important one. 