Study on Water-Rock Interaction in Sea and Freshwater Transitional Zone

Abstract

Study on water-rock interaction in transitional zone through the mixing of seawater and freshwater in different proportion and water-rock Interaction simulation experiments, In the mixing process of sea and freshwater, mixing is the basis of the mechanical mixing with complex chemical process, Total Alkalinity and pH values significantly increase, while the conductivity decreases significantly, calcite and gypsum saturation index increase significantly, while PCO2 reduces. In the course of water-rock role, the saturation indexes of gypsum elevate from -1.06 ~ -0.71 to -0.86 ~ -0.50 after interactions between mixed solution of various proportion and aqueous, which indicates that gypsum dissolves. The saturation indexes of calcite reduce from 0.69 ~ 1.07 to 0~0.10, which indicates that calcite precipitates in the process of experiment, calcite approaches to equilibrium in the end.