Formula 6.40
Hingle nonlinear-resistivity/linear-porosity crossplot
Input(s)
$S_{w}$: Water Saturation (fraction)
$R_{w}$: Formation Water Resistivity (ohm m)
$\Phi$: Mud Filtrate Resistivity (fraction)
a: Pore Geometry Coefficient (Range of 0.35 to 4.78) (dimensionless)
$\mathrm{n}$: Saturation Exponent (dimensionless)
$\mathrm{m}$: Pore Geometry Coefficient2 (Range of 1.14 to 2.52) (dimensionless)
Output(s)
$R_{t}$: Rock Resistivity (ohm m)
Formula(s)
$$ \left(R_{t}\right)^{-\frac{1}{m}}=\Phi *\left(\frac{S_{\mathrm{w}}^{n}}{a * R_{w}}\right)^{\frac{1}{m}} $$
Reference(s)
Bassiouni, Z., 1994, Theory, Measurement, and Interpretation of Well Logs. SPE Textbook Series Vol. 4. Chapter 13, Page: 268.