Using borehole logging to determine the liquid-phase efficient diffusion coefficient

Processes of solute transport in porous media consist of advection, diffusion, dispersion and retardation. Effective diffusion coefficient is always determined in the laboratory by taking undisturbed coring samples and using a special device. A new method of in-situ experiment has been developed by using borehole log associated with understanding geological evolution of the plain, this coefficient was determined through an analytical solution. Boreholes LK87 and LK88 in the Red river delta have been drilled for coring samples and borehole logging. Using laboratory experiment and in-situ experiment, at LK87 effective diffusion coefficients D^∗are 6.3E-10 and 2.80E-10, respectively. At LK88 effective diffusion coefficients D^∗are 3E-10 and 1.70E-10, respectively. The differences of in-situ experiment and laboratory experiment at the same borehole showed that the value of the coefficient is acceptable.