张掖市甘州区地下水中氟的分布规律和成因

在研究张掖盆地水文地质条件的基础上,结合水质测试资料,探讨张掖市甘州区地下水中氟离子空间分布规律并分析其产生原因。结果表明:从山前冲积平原至细土平原,浅层地下水中氟离子浓度逐渐增高;而深层地下水中氟离子浓度变化不明显。细土平原区地下水中氟离子浓度具有随深度的增加逐渐降低的垂直分带规律。丰富的氟物质来源、特殊的水文地质条件和水化学背景是导致甘州区浅层地下水中氟离子富集的主要原因。取用深层地下水是解决高氟区水质性缺水的有效手段。

Distribution and sources of fluorin ion in groundwater in Ganzhou District of Zhangye City

Based on the investigation of hydrogeological conditions and water quality in the Zhangye Basin,the distribution of fluorin ion in the groundwater of Ganzhou District is analyzed.The results show that:(1) the concentration of fluorin ions in shallow groundwater increases gradually from the piedmont alluvial plain to the fine soil plain,while those in deep groundwater show no remarkable change;(2) the concentration of fluorin ions in groundwater of the fine soil plain declines gradually with the increase of vertical depth;and(3) the high concentration of fluorin ions in the shallow groundwater is mainly caused by the rich fluoride sources,the special hydrogeological conditions and the hydrochemical background.It is concluded that utilizing the deep groundwater is a feasible way to prevent water shortage in the regions with high concentrations of fluorin ions.