General form of the Archie equation-Water saturation from resistivity logs
Input(s)
m: Cementation Factor (dimensionless)
a: Tortuosity Factor (dimensionless)
\(\Phi\): Porosity (fraction)
\(R_{w}\): Resistivity of Water (ohm m)
\(R_{t}\): True Resistivity (ohm m)
\(\mathrm{n}\): Saturation Exponent (dimensionless)
Output(s)
\(S_{w}\): Water Saturation (fraction)
Formula(s)
\[
S_{w}=\left(\left(\frac{a}{\Phi^{m}}\right) *\left(\frac{R_{w}}{R_{t}}\right)\right)^{\frac{1}{n}}
\]
Reference(s)
Core Laboratories. 2005. Formation Evaluation and Petrophysics, Page: 45.