龙首山成矿带绿草沟地区铀矿化特征及成因浅析  

Characteristics and Genetic Analysis of Uranium Mineralization in Lyucaogou Area of Longshoushan Metallogenic Belt

作　　者：何佳军 王刚 王伟 刘涛 叶发旺[2] 张川[2] HE Jiajun;WANG Gang;WANG Wei;LIU Tao;YE Fawang;ZHANG Chuan(Research Institute No.203,CNNC,Xi'an,Shaanxi 710086,China;National Key Laboratory of Remote Sensing Information and Image Analysis Technology,Beijing Research Institute of Uranium Geology,Beijing 100029,China)

机构地区：[1]核工业二〇三研究所,陕西西安710086 [2]核工业北京地质研究院遥感信息与图像分析技术国家级重点实验室,北京100029

出　　处：《铀矿地质》2023年第3期395-405,共11页Uranium Geology

基　　金：中国核工业地质局项目(编号:202220-2);核能开发项目“基于航空高光谱与伽玛能谱的铀矿勘查技术研究”(编号:[2021]88)联合资助。

摘　　要：基于最新的找矿成果,对龙首山成矿带绿草沟地区铀矿化特征进行了梳理和总结,结果表明,铀矿化主要定位于中志留世细粒正长岩与古元古界龙首山群塌马子沟组黑云母石英片岩的接触带两侧,受断裂构造、岩性界面和热液蚀变控制。工业矿体厚度稳定,矿化均匀,赋矿岩石为蚀变黑云母石英片岩和蚀变细粒正长岩。铀矿物主要为铀石,呈脉状分布于石英等矿物的边缘和微裂隙中,与黄铁矿、方解石、绿泥石和赤铁矿等共生,也见呈颗粒状镶嵌于赤铁矿中或围绕黄铁矿边缘包裹黄铁矿。地球化学分析结果显示,含矿热液可能为富Ca和碳酸铀酰络合物离子UO_(2)(CO_(3))_(2)^(2–)(或UO_(2)(CO_(3))_(4)^(3-))的中-低温弱碱性或碱性热液,绿草沟地区铀矿化属中-低温热液成因型铀矿化。Based on the latest prospecting results,we have summarized the characteristics of uranium mineralization in Lyucaogou area of Longshoushan metallogenic belt.The results show that the uranium mineralization is mainly located on the both sides of the contact zone between the Middle Silurian fine-grained syenite and the Paleoproterozoic biotite quartz schist of Tamazigou formation of Longshoushan group,and is controlled by the fault structure,lithological interface and hydrothermal alteration.The thickness of the ore body is stable and the mineralization is uniform.The host rocks are altered biotite quartz schist and altered fine-grained syenite.The uranium minerals are mainly coffinites,distributed in the edge and microcrack of quartz and other minerals in vein,and are associated with pyrite,calcite,chlorite and hematite.The uranium is also seen embedded in hematite or wrapped around the edge of pyrite in granular form.The geochemical analysis results show that the ore-bearing hydrothermal fluid may be a medium-low temperature weakly alkaline or alkaline hydrothermal fluid rich in Ca and uranyl carbonate complex UO_(2)(CO_(3))_(2)^(2-)(UO_(2)(CO_(3))_(4)^(3-)),and the uranium mineralization in Lyucaogou area belongs to medium-low temperature hydrothermal type.

关 键 词：铀矿化特征 铀石 地球化学特征 绿草沟 龙首山 

分 类 号：P619.14[天文地球—矿床学]