运用水文地球化学常用分析方法,对柴达木盆地西北部库拉木勒克萨伊河—阿拉尔河流域进行了系统研究,分析了河水中主要离子特征、控制机制及其来源。结果表明:该流域为低矿化度、天然弱碱性淡水;河水类型主要为重碳酸盐型水,部分为氯化物型水;河水中主要离子的化学特征受控于岩石风化作用,流域蒸发作用逐渐显露,阿拉尔河蒸发作用较明显。河水中主要离子来自于岩盐、钾盐、硬石膏、白云石和方解石的风化溶解,并且受到少量溶解于河水中硅酸盐矿物的影响。 Based on the common analytical methods of hydrogeochemistry, the Kalamulexay-Alar River basin in the northwestern Qaidam Basin was systematically studied, and the main ion characteristics, control mechanisms and sources of the river water were analyzed. The results show that the river basin is low salinity and natural weak alkaline freshwater. The type of river water is mainly bicarbonate type water and chloride type water. The chemical characteristics of main ions in river water are controlled by rock weathering. Evaporation gradually revealed, more obvious evaporation role of the Alar River. The main ions in the river water come from the weathering dissolution of rock salt, potash, anhydrite, dolomite and calcite, and are affected by the small amount of silicate minerals dissolved in the river water.