大兴安岭头道桥铌钽矿区地球物理、地球化学特征及找矿标志

Geophysical and geochemical characteristics and prospecting indicators in Toudaoqiao Nb-Ta District,Greater Khingan Mountains

头道桥铌钽矿床位于大兴安岭主脊断裂带西北部,该断裂带是寻找多种有色金属、稀土及稀有金属矿产的重要地段。通过分析成矿地质背景,结合地球物理及地球化学测量结果,对找矿标志进行了总结。满克头鄂博组、深部花岗斑岩、含有烧绿石的岩石均可作为直接找矿标志;高阻低极化异常为矿区找矿的地球物理标志;矿区成矿作用以Nb、Ta为主,Li、Be、Th可作为找矿的指示元素;对圈定的土壤综合异常进行查证,探获了矿体,表明由Nb、Ta等主成矿元素组成的异常可作为找矿的地球化学标志。综合利用地质、地球物理、地球化学方法进行找矿是十分有效的手段,可为周边地区找矿提供借鉴。

Toudaoqiao Nb-Ta Deposit is located in the northwest of the main ridge fault zone of Greater Khingan Mountains.The fault zone is an important area to search for a variety of non-ferrous metals,rare earth and rare metal minerals.In this paper,the metallogenic geological background and the geophysical and geochemical survey results are analyzed,and the prospecting indicators are summarized.Manketouebo Formation,deep granite porphyry and pyrochlore-containing rocks can be direct prospecting indicators.The high resistivity and low polarization anomaly is the geophysical indicator for prospecting in the district;the mineralization in the district is dominated by Nb and Ta,and Li,Be and Th can be prospecting indicator elements;the delineated soil comprehensive anomalies are verified and ore bodies are discovered,indicating the anomaly composed of main ore-forming elements such as Nb and Ta can be geochemical indicators for prospecting.Comprehensive unitization of geological,geophysical and geochemical methods is effective means for prospecting.The research can be used as reference for prospecting in peripheral area.