A method is proposed for obtaining effective permeabilities of heterogeneous porous media at many length permeabilities of heterogeneous porous media at many length scales. The real space renormalization group method (RSRG) has been modified to determine the effective properties of both uncorrelated and correlated permeability fields. The model shows excellent sensitivity to directional permeabilities and to the type of heterogeneity. In addition to two component shales and sequences, the method is extended to calculate effective properties of as many as four components. The method is also applied to obtain the 'effective' two phase relative permeability curves for porous media that are heterogeneous at the macroscopic or megascopic length scales. These effective properties are inputs into numerical simulators and can be used to interpret log and core derived properties.