大兴安岭乌兰哈达地区铀矿找矿进展与找矿预测

Prospecting progress and prognosis of uranium deposits in Ulanhada area,Daxinganling

内蒙古乌兰哈达地区位于大兴安岭林西-扎兰屯多金属成矿带上,属于扎兰屯火山岩型铀成矿远景带。通过1/5万伽玛能谱测量工作发现工区内古生代、中生代地层U背景值1.88×10^(-6)~2.54×10^(-6),海西期花岗岩U背景值为3.74×10^(-6),具备很好的铀源条件。该区断裂构造及层间破碎带发育,为铀矿运移提供通道和沉淀的场所。粘土矿化、萤石化等热液蚀变发育,可以作为铀矿找矿的热液蚀变标志。通过放射性测量工作圈定9处铀异常区,发现2处铀矿化带,圈定了2个找矿靶区,为该地区铀矿找矿指明了方向。

The Ulanhada area located in Linxi-Zhalantun polymetallic metallogenic belt of Daxing'an Mountains in Inner Mongolia which belongs to Zhalantun volcanic rock type uranium resources prospecting belt.Through 1/50000 gamma-ray spectroscopy survey and comprehensive study of the uranium metallogenic geological conditions in this area,we found:1)the U background values of Paleozoic and Mesozoic strata in the work area are(1.88~2.54)×10^(-6),and that of Hercynian granites are 3.74×10^(-6),which have good uranium source conditions;i2)the fault structures systems and interlayer fracture zones are in favor of uranium migration and precipitation;iii)the hydrothermal alterations such as clayization and fluoritization can be used as a sign for uranium ore prospecting.After the radioactivity survey,nine uranium anomaly areas and two uranium mineralization zones were identified.Two prospecting areas are targeted.These work pointed out the directions for prospecting uranium resources in this area.