崇安地区铀矿成因与矿区断裂构造的关系

摘要

崇安地区位于武夷-云开-台湾造山系华夏地块桃山-诸广岩浆弧北部东缘部位,其东侧与武夷山基底断隆带毗邻,断裂构造极其发育.断裂构造发育在地壳的不同深度和圈层,对各种矿化起着不同的控制作用.笔者通过对区内控矿构造和铀矿化主要地质特征的分析,论述了断裂构造与铀成矿的关系,认为断裂构造不仅为成矿流体的运移提供了通道,为成矿物质提供了沉淀富集的场所,而且还影响着铀矿床的空间分布、成矿力学环境、成矿物理化学条件等.该区断裂构造具有多期活动的特点,具有压性、压扭性、张性、张扭性等性质.岩浆期后含矿热液沿火山盆地盖层与基底接触的构造破碎带或外带的构造破碎带运移,并在破碎带中充填、交代而形成铀矿体.因此,断裂构造是铀成矿的必要条件,与成矿有着密切关系.%Chong'an area is located in the eastern margin of northern Taoshan-Zhuguangshan magmatic arc of Wuyi-Yunkai-Taiwan orogenic sysytem. The east side of the area is adjacent to the basement uplift of Wuyi Mountain, and the faults is developed extremely. Faults developed at different depths in the crust play a different role in controlling the mineralization. Through the analysis of ore-controlling structures and the main geological features of uranium mineralization, the relationship of the faults to uranium mineralization is discussed, faults in the area is characterized by multi-period activities, with dynamics of compressibility, pressure-shear, tensile, tensile-shear. The faults not only provide a channel for ore forming fluid migration, and the precipitation place of minerals, but also affects the mechanical environment , physical and chemical conditions of mineralization. Along the fracture zone and outer contact zone between the cover and basement of the volcanic basin, the ore-bearing hydrothermal fluid migrated and filled into the fractural tissues which resulted in the metasomatism and mineralization. Therefore, the fault structure is a necessary condition for mineralization, and has a close relationship with the mineralization.