Formation water resistivity (Rw)determination: The SP method

Abstract

Formation water resistivity represents the resistivity value of the water (uncontaminated by drilling mud) that saturates the porous formation. It is also referred to as connate water or interstitial water. Its resistivity can be
determined by a number of methods, one of which is by the SP curve discussed in this work. Analysis of wire-line log data depends on the assumption that the only conductive medium in a formation is the pure water which supplies the energy and drive in reservoirs. So, physical properties of this formation water can be determined, one of which is its electrical resistivity and this eventually leads to water saturation determination – an important aspect of reservoir evaluation. This
paper presents a review and comparative assessment of the graphical, vis-à-vis the calculative means of Rw determination by the SP method