湖南邓阜仙钨铌钽矿花岗细晶岩接触带白云母<sup>40</sup>Ar/<sup>39</sup>Ar年龄及其地质意义

湖南邓阜仙钨铌钽矿花岗细晶岩接触带白云母⁴⁰Ar/³⁹Ar年龄及其地质意义

摘要: 邓阜仙钨铌钽矿是锡田地区最为重要的钨锡多金属矿床之一。利用⁴⁰Ar/³⁹Ar同位素测年方法对金竹垄铌钽矿段花岗细晶岩顶部条带状白云母长石石英岩中的白云母进行了年龄测试，结果表明，⁴⁰Ar/³⁹Ar同位素坪年龄为148.3±1.1Ma，形成时代为晚侏罗世。结合锡田地区已有的年代学资料，认为包括邓阜仙钨铌钽矿在内的锡田地区钨锡多金属矿具有相同的成矿地质背景，为华南地区中生代岩石圈大范围伸展-减薄作用的产物。

Abstract: The Dengfuxian W-Nb-Ta deposit is one of the important W-Sn multi-metal ore deposits in Xitian area of Hu'nan Province. ⁴⁰Ar/³⁹Ar dating of muscovite for the sample collected from the top of granite-aplites in Jinzhulong Nb-Ta zone yielded a ⁴⁰Ar/³⁹Ar plateau age of 148.3±1.1Ma, suggesting that the ore-forming process occurred in Late Jurassic. Combined with the existing chronological data of the Xitian area, the authors hold that the W-Sn multi-metal ore deposits of the Xitian area including the Dengfuxian W-Nb-Ta deposit had the same geodynamic condition, and were formed by the extension and thinning of the Mesozoic lithosphere in South China.