西藏安丁俄玛地区花岗岩型铀矿化特征及控制因素分析

Analysis of Characteristics and Controlling Factors of Granite Type Uranium Mineralization in Andingoma Area,Tibet

安丁俄玛地区位于仲巴县琼果乡,现已发现1条铀矿化带及众多异常点、带。通过在该区开展地质测量、地面伽玛能谱测量、槽探、样品分析等工作,结合安丁俄玛地区铀矿化点、带,分析了该区的铀矿化特征。结果表明,始新世似斑状二长花岗岩为主要赋矿岩体,北西—南东向及近东西向次级断裂构造是该区控矿构造,硅化、绢云母化、褐铁矿化等热液蚀变与矿化密切相关。安丁俄玛地区铀矿化受侵入岩体岩性、构造、热液蚀变等控制,次级断裂及沿次级断裂贯入的中酸性脉体为铀元素的运移及富集提供了通道。安丁俄玛地区存在花岗岩型铀矿的成矿条件,是寻找花岗岩型铀矿的有利地段。

The Andingoma area is located in Qiongguo Township,Zhongba County,one uranium mineralization zone and many abnormal points and abnormal zones have been found.By carried out geological surveys,ground gamma spectrometry survey,trenching engineering,and sample analysis in this area,combined with the uranium mineralization points and uranium mineralization zones in the Andingoma area,the uranium mineralization characteristics in this area were analyzed.The results that the eocene porphyritic monzogranite is the main orehosting rock mass,and the NW-SE and NEW trending secondary fault structures are the orecontrolling structures in this area.The hydrothermal alterations such as silicification,sericitization,and limonite are closely related to mineralization.The uranium mineralization in the Andingoma area is controlled by the lithology,structure and hydrothermal alteration of the intrusive rock mass,and the secondary faults and intermediate-acid veins penetrating the secondary faults provide pathways for the migration and enrichment of uranium.There is a condition of granite uranium deposit in Andingoma area,which is favorable for prospecting granite uranium deposit.