贵州纳雍水东铅锌矿床成因的探讨

The Discussion of Genesis of Lead-zinc Deposit in Shuidong,Nayong of Guizhou

贵州纳雍水东铅锌矿床位于扬子地台西缘,是黔西北铅锌矿区的重要组成部分。区内铅锌矿具有构造控矿的明显特征,矿体主要产于上震旦统灯影组地层主次断裂交汇处或断层破碎带中。铅锌矿源层初步形成于晚震旦世,基底的铅锌物质和海侵带来的陆源物质被藻类吸附与硫离子团结合形成金属硫化物矿源层。包裹体研究表明,矿源层形成后,至少经历了大规模成矿作用和后期叠加改造两期成矿作用,并划分出成矿物质的初步富集、大规模铅锌矿富集成矿和后期构造运动对铅锌矿形态的改造三个成矿阶段,对应于矿源层形成和两期成矿作用。通过与典型MVT型、SEDEX型铅锌矿床地质地球化学特征对比,认为纳雍水东铅锌矿床类型属于典型的MVT型铅锌矿床,并提出了找矿标志和建议。

The lead-zinc deposit of Guizhou Nayong Shuidong lies in the west of Yangtz platform, it is an important part of lead-zinc concentration area in northwestern Guizhou. Deposits in the area with the apparent characteristics of ore-controlling structure, ore body are mainly the upper Sinian Dengying forma- tion inter the primary and the secondary fracture or fault fracture zone. Source layer formed in deposits pre- liminary the late simian and base material of lead and zinc and bring land-origin transgression material to be algae adsorption and sulfur group formed with metal sulfide beds. Inclusion research shows that after source layer formed, the metallogenic experiencing at least the large-scale metallogeny and late transforma- tion period superposition. Corresponding to the formation and two beds of mineralization, it is to be divided into the enrichment of ore-forming materials, large-scale lead-zinc mine preliminary enrichment and later structure of lead-zinc deposit of reform of the movement form three metallogenic phase. In contrast to MVT type with SEDEX type lead-zinc deposits geology geochemical characteristics. We draw the conclusion that Nayong Shuidong lead-zinc deposit types belongs to the typical MVT type lead-zinc deposits, and put forward the prospecting marks and suggestions.