粤北下庄铀矿田脉石矿物Sr、Nd、Pb同位素地球化学研究  

Sr, Nd and Pb isotopic geochemistry of gangue minerals in the Xiazhuang uranium orefield,northern Guangdong Province

作　　者：商朋强[1,2,3] 胡瑞忠[2] 毕献武[2] 张国全[2] 田建吉[4] 

机构地区：[1]中化地质矿山总局地质研究院,河北涿州072750 [2]中国科学院地球化学研究所矿床地球化学国家重点实验室,贵州贵阳550002 [3]中化地质矿山总局,北京100101 [4]核工业北京地质研究院,北京100029

出　　处：《中国地质》2012年第6期1847-1856,共10页Geology in China

基　　金：中国科学院知识创新工程重要方向项目(KZCX3-SW-125);国家杰出青年科学基金(49925309)资助

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。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.

关 键 词：Sr、Nd、Pb同位素 下庄铀矿田 脉石矿物 成矿物质 成矿流体 

分 类 号：P619.14[天文地球—矿床学]