  In this paper, by combining of fractional centered difference approach with
alternating direction implicit method, we introduce a mixed difference method
for solving two-dimensional Riesz space fractional advection-dispersion
equation. The proposed method is a fourth order centered difference operator in
spatial directions and second order Crank-Nicolson method in temporal
direction. By reviewing the consistency and stability of the method, the
convergence of the proposed method is achieved. Several numerical examples are
considered aiming to demonstrate the validity and applicability of the proposed
technique.
