Petrophysical Studies For Some Lower Cretaceous Formations, Western Desert, Egypt

Abstract

The Kharita, the Dahab and the Alamein Formations are representing the upper part of the Lower Cretaceous rock sequence in the northern part of the Egyptain Western Desert. Some core samples have been obtained from these rock units. . They are subjected for both electrical resistivity and rock porosity measurements. •'_ . Formation factor-porosity relations at four different brine concentrations have been performed. Petrophysical exponents (a, m & n) of the Archie's general formulae have been determined at the in situ formation water resistivity (R,, =0.72 . Ohm.m.). They are very helpful to perform an effective well-log interpretation for the studied intervals. In addition, the correlated relationship between the variations in the interval velocities as a petrophysical character and the existing lithofacies changes in these above mentioned formations have been investigated.