青海省都兰县洪利铅锌矿床地质特征及找矿标志

Geological Characteristics and Prospecting Symbols of Hongli PlumbumZinc Deposit in Dulan County of Qinghai Province

摘要:

青海省都兰县洪利铅锌矿床地处华南板块与柴达木盆地南缘的接合部，位于东昆中断裂带内，总体构造线走向为NW-SE向，构造形迹以断裂、褶皱为主，矿区断裂构造发育，按其走向可划分为2组，即NW，NE向断裂。其中NW向断裂为区内主干断裂，略具规模，控矿明显，为区内主要的导、控矿构造，洪利铅锌矿床即受其控制。次为NE向断裂，但规模不大，且对矿体具错断和破坏作用。区内岩浆活动多集中于晋宁期和华力西期，成矿地质条件较好。受后期构造活动影响，造成了该矿床由于矽卡岩化与热液蚀变在空间上的叠加而使其矿化特征的复杂多变。通过详细的野外观察和室内分析共圈出锌多金属矿体2个，磁铁矿体6个，金矿体2个，铁矾帽9个。根据围岩蚀变、矿体走向、分布特征及其与岩性、构造的关系，可分为南、北2个矿段，初步划分了Ⅰ，Ⅱ，Ⅲ条矿化带。研究认为铁矾帽、磁异常、地球化学、矽卡岩化、热液蚀变及角岩化是该区的主要找矿标志，其中铁矾帽系该矿区找矿的直接标志。

Abstract:

On the basis of the former achievements, combining with a large number of field investigation and collation and research work indoor, geological characteristics of lead-zinc deposits, distribution rule, mineralization types as well as important prospecting symbols of Hongli plumbumzinc deposit in Qinghai province have been studied. It is regarded that iron alum cap, magnetic anomalies, geochemical, skarn, hydrothermal alteration and hornfels are main prospecting symbols in this area. Among them, iron alum cap is direct sign for subsequent prospecting exploration work.