柴达木盆地那棱格勒河及其尾闾盐湖铷、铯物源和富集过程研究

Sources and Enrichment Processes of Rubidium and Cesium in the Nalengele River and its Terminal Lakes,Qaidam Basin

铷、铯作为关键金属矿产,在诸多高新科技领域具有举足轻重的地位,其需求量逐年增加。柴达木盆地那棱格勒河及其尾闾盐湖中铷、铯含量较高,查明其物质来源和迁移富集过程,对柴达木盆地铷、铯关键金属成矿作用研究和资源增储具有重要意义。本研究以那棱格勒河流域的河水、地下水、沉积物、盐湖卤水和岩浆岩为研究对象,通过开展铷、铯元素含量分析,结合前人研究成果,探讨了那棱格勒河及其尾闾盐湖的铷、铯成矿作用。研究结果表明,湖区铷、铯元素含量表现为晶间卤水明显高于湖表卤水,且晶间卤水中铷、铯含量按照东台、西台、一里坪、涩聂湖的顺序逐渐降低。尾闾盐湖中高度富集的铷、铯与布喀达坂区域深部岩浆流体和高温水-岩反应有关,其以热泉的形式将铷、铯由深部携带至地表并通过洪水河-那河体系对湖区进行补给。补给过程中河水铷、铯的浓度受地下水输入、蒸发作用和沉积物吸附作用的共同影响,而湖区强烈的蒸发浓缩作用是盐湖卤水铷、铯发生富集的关键,沉积物对盐湖卤水长时间的吸附作用致使该区域具有形成沉积型铷、铯矿床的潜力。

Rubidium(Rb)and cesium(Cs),as critical metal elements,have seen a steady increase in de‐mand due to their significant roles in high-tech fields.In the central Qaidam Basin,the Nalenggele River and its terminal saline lake exhibit relatively high concentrations of Rb and Cs.Unraveling the sources of these metals and their migration and enrichment mechanisms hold substantial significance for understanding Rb and Cs ore-forming processes and resource augmentation efforts within the Qaidam Basin.This study fo‐cuses on the Nalenggele River system,including river water,groundwater,sediments,brine and igneous rocks.Through elemental concentration analysis and integration with prior research findings,it explores the ore-forming mechanisms of Rb and Cs in both the river and the terminal saline lake.The study findings indi‐cate that within the lake region,the content of Rb and Cs is notably higher in intercrystalline brines com‐pared to surface brines.Furthermore,there exists a descending trend in the concentration of Rb and Cs within intercrystalline brines across the sequence of Dongtai,Xitai,Yiliiping and Senie.The highly en‐riched Rb and Cs in the terminal lakes are related to the deep magmatic fluids and high-temperature water rock reactions in the Bukadaban region.They are carried from the deep to the surface in the form of hot springs and supplied to the lake area through the Hongshui-Nalenggele River system.During this process,the concentrations of Rb and Cs in the river water are influenced by inputs from groundwater,evaporation effects and adsorption.The intense evaporation concentration in the lake region plays a pivotal role in the enrichment of Rb and Cs in the brine.Moreover,sediments have the potential to form sedimentary Rb and Cs deposits due to their prolonged adsorption on brine.