DEPOSITION IN FRACTURES

Fractures are relatively planar discontinuities in rocks induced by the huge internal stresses which are created by the slow but constant motions of the underground masses. Deposition of a single solute in a single fracture is addressed in the limit where the geometrical changes are very slow compared to the average fluid velocity. The deposition fluxes are calculated by means of a finite-difference scheme which is much more efficient than random walks. Examples of deterministic fractures, random but uncorreiated fractures, Gaussian and self-affine fractures are studied for four different values of the Peclet and the Peclet-Damkohler numbers. Some general trends are discussed.