THE FRACTAL DIMENSION OF PORES IN SEDIMENTARY-ROCKS AND ITS INFLUENCEON PERMEABILITY

Perimeter-area power-law relationship of pores in five sedimentary roc ks are estimated from scanning electron micrographs of thin sections. These relationships for the pores of four sandstones were found to lie between 1.43 and 1.49, while that of an Indiana limestone was found t o be 1.67. We show how the perimeter-area power-law relationship of po res, along with a pore-size distribution, can be used to estimate the hydraulic permeability. A discussion is given of how the fractal dimen sion of the pore perimeter derived by Mandelbrot for islands whose bou ndaries are fractal: P=epsilon(D)A(D/2), where epsilon is some constan t that depends on the length of the measuring grid size and D is the f ractal dimension of the pore perimeter, influences permeability. (C) 1 997 Elsevier Science B.V.