“三滩”水源地地下水演化及地球化学模拟

Evolvement of Hydrochemical Characteristics and Geochemical Modeling of Water Source Area of Santan in Lanzhou City

为探索兰州市"三滩"水源地水质恶化原因,基于兰州"三滩"水源地不同历史时期的水化学数据,结合对含水层结构的分析,采用反向水文地球化学模拟方法计算了南部高TDS地下水对水源地的补给量以及矿物相转化量。模拟结果从水化学角度进一步证实了南部黄土台塬区咸水入侵是马滩水源地地下水水质恶化的主要原因;水源地西侧的深沟断层割裂了咸水区与盆地的水力联系,这一特殊的水文地质结构是崔家大滩水质变化不大的主要原因。

Deterioration of water quality was observed in the water source area of Santan in Lanzhou City for over 40 years. The change of water quality by recharge of high TDS groundwater from the south was modeled by reverse geochemical modeling. Historical water quality test results and the distribution of aquifers were used to support the modeling. The results verify that the intrusion of saline water from south is the main causation of the deterioration of water quality in Matan water source area and the recharge of saline water to Cuijiadatan water source area is blocked by Shengou deep fault and prevented the drastic change of water quality in this water source field.