Correlation of mud cake resistivity to mud resistivity

Input(s)

$R_{m}$: Mud Resistivity (ohm m)

$R_{m f}$: Mud Filtrate Resistivity (ohm m)

Output(s)

$R_{m c}$: Mud Cake Resistivity (ohm m)

Formula(s)

$$ R_{m c}=0.69 * R_{m f} *\left(\frac{R_{m}}{R_{m f}}\right)^{2.65} $$

Reference(s)

Bassiouni, Z., 1994, Theory, Measurement, and Interpretation of Well Logs. SPE Textbook Series Vol. 4. Chapter 4, Page: 67.