中文摘要：

下庄铀矿田为中国南岭地区重要的铀矿基地,矿区内分布有规模大小不等的数个铀矿床。为解决近年来争议较多的该区铀矿床矿质和流体来源问题,本次对下庄矿田铀矿床中的脉石矿物开展了系统的Sr、Nd、Pb同位素地球化学研究。结果表明,本区与成矿有关的碳酸盐矿物富集放射性成因铅,矿床中的Pb和U主要源于帽峰式花岗岩。Sr、Nd同位素组成显示成矿流体主要为壳源,南部矿区部分矿床的成矿流体在上升及矿质沉淀过程中与基性脉岩发生水-岩反应而使其形成的脉石矿物的Sr、Nd同位素组成具有壳幔两端元混合的特征。

英文摘要：

The Xiazhuang uranium orefield is an important uranium producing area in Nanling region,where there exist many ore deposits.To solve the much controversial problems of the origin of uranium and the ore-forming fluid,this research is focused on Sr,Nd and Pb isotopic geochemistry of the gangue minerals.The results show that the carbonate has rich radioactive lead.The lead and uranium mainly came from such granitic rock bodies as Maofeng granite.The compositions of Sr and Nd isotope show that the ore-forming fluid was mainly derived from the crust.The water-rock interaction between the ore-forming fluid and the basic dike rock during the upward migration of the ore-forming fluid and the precipitation of uranium formed the feature of binary composition of the gangue minerals.