... for the determination of water resistivity, but the published correlations of Rw(e) vs. Rw for "average fresh waters" do not extend to the resistivity of potable water. A formula presented by Gondouin, Tixier, and Simard to correct the SP for divalent cations can be used to calculate the SP from water analysis...

... log analysis concentration well logging water quality mud filtrate divalent cation NaCl solution formation factor evaluation Formation Resistivity Factor permeability water well determination resistivity grain size interpretation Formation Resistivity INTERPRETATION OF ELECTRIC LOGS...