This crossplot is used for porosity and lithology determination from the litho-density log and compensated neutron log. The overlay lines are based on a borehole filled with a fluid of density equal to 1000 kg/m3, and dolomite density is set at 2850 kg/m3. The crossplot is from Schlumberger's Chart book (2000) and is applicable to CNL logs after 1986 labeled TNPH.
Input cells are in yellow. Enter the average bulk density and apparent neutron sandstone porosity for the zone of interest. The associated data point is plotted on the crossplot as a green dot.