华北平原中部重碳酸钠型水的成因探讨

通过采集的大量地下水样品测试结果发现，华北平原中部的衡水——德州一带，深层地下淡水多为重碳酸钠型水。本文利用地下水循环理论及地球化学理论，探讨华北平原中部地下水重碳酸钠型水的成因。研究结果表明：华北平原中部地下水来源于大气降水的淋滤补给，后期水岩相互作用，离子产生迁移，特别是阳离子交换作用，致使地下水中钙离子缺失，钠离子富集，形成重碳酸钠型水。同时，在碱性环境中，地下水中氟离子富集，含量升高。

Discussion about the causation of sodium bicarbonate type water come into being in the midland of Huabei Plain

Through collecting the test data of large number of groundwater samples , the result has been found that most of deep groundwater belongs to sodium bicarbonate type water in the area such as Heng- shui and Dezhou of the central North China Plain. By use of theory of groundwater cycle and geochemis- try, the paper discussed about the origin of sodium bicarbonate type water formed in the central North China Plain . The results show that the groundwater of the area is from precipitation, it has the character- istics of leaching witch is affected by post - water - rock interaction and positive ion exchange action, witch makes the calcium in groundwater be absent and the sodium enrichment, the sodium bicarbonate type of water is formed. Meanwhile, the fluoride ions in groundwater enrich and their content increase in the alkaline environment.