柴达木盆地那棱格勒河流域表层沉积物中锂的分布特征

Distribution Characteristics of Lithium in Surface Sediments of Nalinggele River,Qaidam Basin

柴达木盆地四湖区卤水锂资源极为丰富,那棱格勒河是其最重要的补给源,查清那棱格勒河流域表层沉积物中锂的分布和赋存特征对深刻理解卤水锂富集成矿过程具有重要意义。以那棱格勒河流域表层沉积物为研究对象,探讨了其中锂的赋存特征及分布规律。结果表明,研究区表层沉积物以砂和粉砂为主,锂主要赋存在粉砂和黏土粒级沉积物中;黏土矿物组成以伊利石和伊蒙混层为主,高盐度卤水环境有利于黏土矿物形成。元素地球化学分析显示,锂主要赋存在伊蒙混层矿物中,较高含量的K对于Li进入伊利石矿物晶格具有一定的抑制作用,Li和B在地质过程中应具有相似的地球化学行为。

Lithium resource was rich in Yiliping,West Taijinar,East Taijinar and Qarhan salt lakes in Qaidam basin,and Nalengele River was the most important supply source for these four lakes.Identifying the distribution and occurrence characteristics of lithium in surface sediments of Nalngele River is of great significance for understanding the enrichment and mineralization process of lithium in brine.In this work,we focused on the surface sediments in Nalengele River basin,and the characteristics and distribution of lithium was investigated.The results showed that the surface sediments in this area consisted of sand and silt,and lithium mainly occurred in silt and clay-grain sediments.The clay minerals were mainly composed of illite and illite-smectite mixed layers,and the high salinity brine environment was beneficial to the formation of clay minerals.The elemental geochemical analysis indicted that lithium mainly occurred in the illite-smectite mixed layers,and the high content of K inhibited Li entering into the lattice of illite.The similar variation between Li and B indicated that they had the similar geochemical behaviors during the geological process.