Tracer diffusion coefficients in sedimentary rocks: correlation to porosity and hydraulic conductivity

摘要

Matrix diffusion is an important transport process in geologic materials of low hydraulic conductivity. For predicting the fate and transport of contaminants, a detailed understanding of the diffusion processes in natural porous media is essential. In this study, diffusive tracer transport (iodide)was investigated in a variety of geologically different limestone and sandstone rocks. Porosity, structural and mineralogical composition, hydraulic conductivity, and other rock proper- Ties were determined. The effects diffusion coefficients were measured using the time-lag Method.