西藏达龙钨钼矿床地质特征及成矿环境研究

Geological characteristics and mineralization environment of Dalong W-Mo deposit in Tibet

西藏达龙钨钼矿床位于冈底斯成矿带东段北侧,受达龙区域断裂带控制。矿体呈脉状、板状、囊状产于硅化石榴石板岩、透辉石矽卡岩中。WO 3平均品位0.212%；Mo 平均品位0.091%；Zn 平均品位3.10%。流体包裹体测温结果显示钨钼成矿温度为320℃,铜锌矿化发生在200℃。硫同位素δ34 S测定为3.5‰~5.5‰,说明成矿物质具深源特征。辉钼矿 Re-Os 年龄测定,模式年龄介于63.2~68.1Ma,成矿发生在喜山早期。钨钼成矿主要与黑云母花岗闪长岩侵位形成的矽卡岩化有关。

Dalong W-Mo deposit in Tibet locates at the northern side of eastern section of Gangdese metallo-genic belt which is controlled by Dalong regional fault zone.The ore-bodies occur in silicified garnet slates and diopside Skarn in veined,slabby and vesiculate shapes.The average grade of WO 3 is 0.212%,while that of Mo is 0.091% and that of Zn is 3.10%.The fluid inclusion thermometry shows that the formational tem-perature of W-Mo is 320℃ while that of Cu-Zn is 200℃.The sulfur isotopeδ34 S is determined in the range of 3.5‰~5.5‰ which indicates that the metallogenic materials are deep seated source.According to the Re-Os dating of molybdenite,its model age is within the range of 63.2 ~ 68.1Ma and its mineralization period is early Himalayan stage.The mineralization of W-Mo is primarily related to skarnization formed from em-placement of biotite granodiorite.