Resistivity of Brine-Saturated Sands in Relation to Pore Geometry

A method has been devised for the direct determination of the tortuosity of pore channels in porous rock. The tortuosity, a geometrical parameter, together with the porosity, determines the resistivity factor. Experimental determinations made on a suite of sandstone samples selected to cover a wide range of texture have shown that (1) tortuosity values were lower than had been previously supposed, (2) the resistivity factor is related to porosity and tortuosity, (3) the resistivity factor correlates with the packing index, and (4) the resistivity factor can be approximated by means of a relation involving only resistivity factor and porosity.