Compositional Variation of Major Elements in Groundwater Caused by Water-Rock Interaction (II)

Influence of Reaction Kinetics and Fluid Flow

Abstract

Compositional variation of major elements in groundwater interacting with rocks (Na Ca-feldspar) was derived based on dissolution kinetics-fluid flow coupling model. Using this theoretical equation and assuming reasonable values of important parameters governing this equation, A/M (A: surface area of feldspar, M: mass of aqueous solution) and τ (residence time of groundwater) were estimated. The width of crack was estimated from the A/M values. This estimated width of crack is different from laboratory values. This disagreement may be due to the different width of crack in handspencimen used for the laboratory experiments and that in the rocks in the natural catchment.