酒泉-金塔盆地水化学特征及其演化规律

Geochemical characteristics and evolution of groundwater in Jiuquan-Jinta Basin

通过对观测资料的分析及PHREEQC软件的反向地球化学模拟,对酒泉—金塔盆地地下水水化学特征及其演化规律进行了研究.分析结果表明:酒泉、金塔盆地地下水具有相似的化学特征及演化规律,沿地下水流方向水化学类型由HCO_3^--SO_4^(2-)型向SO_4^(2-)型过渡,均发生了CaCO_3的沉淀、CaMg(CO_3)_2的溶解、CaSO_4·2H_2O的溶解、NaCl的溶解及CO_2的析出.金塔盆地地下水主要受由酒泉盆地流入的地表水影响,而与酒泉盆地地下水联系不大.

Abstract： The geochemical characteristics and evolution of groundwater in Jiuquan-Jinta Basin were studied by analyzing the observed data and using the PHREEQC, an inverse modeling software for chemical reactive transport processes in ground water. The results showed that groundwater evolves gradually from HCO3^-- SO4^2- type water to more mineralized SO4^2- type water. Dissolution of dolomite, gypsum, halite and calcite precipitation as well as CO2 separate-out are the main mechanism causing the salinization of the groundwater. Mixing and evaporation effects characterize the groundwater of Jinta Basin and there is little correlation of groundwater between these two areas.