赣东北朱溪超大型钨矿床中白钨矿的稀土、微量元素地球化学特征及其Sm-Nd定年

发布时间：2018-05-12 16:46

  本文选题：朱溪钨矿 + 白钨矿　； 参考：《地学前缘》2017年05期

【摘要】：赣东北朱溪超大型钨矿床是目前世界上最大的夕卡岩型钨矿床,为确定其成矿物质来源及成矿时代,在详细钻孔岩心编录基础上,本文对白钨矿运用LA-ICP-MS法分析了其单矿物的微量元素、稀土元素,并进行Sm-Nd同位素定年研究。结果显示:白钨矿微量元素中Mo、Nb、Ta富集,而Rb/Sr0.04,Nb/Ta=1.69~8.46、Zr/Hf=3.06~6.75,显示成矿物质的壳源特征。白钨矿的∑REE变化大(∑REE=3.25×10~(-6)~229.95×10~(-6)),LREE与HREE之间分馏明显((La/Yb)N=36~19 984),属于轻稀土富集型。依据δEu值的特征,将白钨矿分为δEu正异常(δEu=1.44~9.06)的轻稀土富集型和δEu负异常(δEu=-0.25~-0.82)的轻稀土富集型;在空间上,由远到近接近花岗岩,白钨矿的∑REE逐渐升高,δEu由正异常逐渐转变为负异常,有与花岗岩稀土配分曲线趋于一致的趋势。白钨矿Sm-Nd等时线年龄为(144±5)Ma,143 Nd/144 Nd初始比值为0.512 020,其εNd(t)为-9.753,二阶段模式年龄为1 745 Ma,其年龄与物质来源与朱溪花岗岩的一致,表明朱溪钨矿床是朱溪矿区隐伏花岗岩进一步演化的产物。
[Abstract]:The Zhuxi super large tungsten deposit in northeastern Jiangxi is the largest skarn type tungsten deposit in the world at present. In order to determine its source of ore-forming material and metallogenic epoch, it is based on the detailed cataloguing of borehole cores. In this paper, the trace elements and rare earth elements of Scheelite are analyzed by LA-ICP-MS method, and the Sm-Nd isotopic dating is carried out. The results show that Mo-NbPn-Ta is enriched in wolframite trace elements, while RB / Sr0.04Nb / Ta 1.69Nb / Ta 1.69nb / HF 3.06C 6.75, which shows the crustal characteristics of the ore-forming materials. The 鈭，

本文编号：1879371