石家庄平原地下水化学演化的质量平衡模拟

MASS BALANCE MODELING OF THE EVOLUTION OF GROUNDWATER CHEMISTRY IN THE SHIJIAZHUANG PLAIN

石家庄平原地下水化学演化具有明显的分带性规律,本文应用质量平衡模拟理论对其形成的水岩作用机理进行了研究,模拟结果表明,控制研究区水化学演化的主要水岩作用过程为:石膏、斜长石、黑云母的溶解,石英、伊利石的沉淀,方解石在上游主要表现为溶解,而在下游地段渐趋沉淀,在上游地段还发生了钙蒙脱石的沉淀,下游地段发生阳离子交换作用,这些水岩作用过程造就了石家庄平原的水化学分带性特征。

Groundwater of the Shijiazhuang plain have the characteristics of hydrochemical zoning typical of semiarid areas in North China. The chemical types change in the sequence of HCO3-Ca→ HCO3-Ca . Mg→HCO3-Na . Ca . Mg-- HCO3- Na . Ca(Mg) in the flow direction. Mass balance models were applied to investigate the water-rock interaction processes. The results show that the water-rock interaction processes controlling the formation of chemical components of groundwater include precipitation/dissolution of andesine, biotite, gypsum, quartz, illite and Ca-semitite and exchange of Ca2+/Na+ and Mg2+/Na+.