大新矿床构造地球化学分带及铀多金属成矿规律研究

Study on structural geochemical zonation and uranium polymetallic metallogenic regularities of Daxin deposit

大新矿床产出于直接覆于上寒武统之上泥盆系间的构造破碎带中。笔者对该破碎带进行了详细地质调查和系统取样分析,研究表明,该破碎带发育从原岩带→碎裂岩带→构造泥→糜棱岩带→构造角砾岩带的构造地球化学分带规律。随着构造破碎带破碎程度的增强,U、Mo、As、Sb、Re和Tl等元素同步增高。铀多金属矿化对围岩无选择性,仅与破碎带的存在相关联,而且矿化程度与破碎强度呈同步消长关系,由此认为,大新矿床属于受构造破碎带控制的铀多金属热液矿床。

Daxin deposit occurs in structural fractured belt in Devonian,which lies directly on Upper Cambrian.Through detailed geological survey and systematic analysis on samples,it is proven that the fractured belt may be divided in the structure and geochemistry as protolith zone→cataclasite zone→tectonic mud zone→mylonite zone→tectonic breccia zone.In the structural fractured belt,the stronger the fracture occurs,the higher content of elements will be,such as U,Mo,As,Sb,Re,Tl,etc.The uranium polymetallic mineralization is not related to wall rock,but associated with the existence of fractured belt.There is positive correlation between the mineralization degree and the fracture intensity.Therefore,it is considered that Daxin deposit belongs to uranium polymetallic hydrothermal deposit controlled by structural fractured belt.