Resistivity of a water-saturated shaly sand (Vsh models)

Input(s)

$R_{w}$: Formation Water Resistivity (ohm m)

$V_{s h}$: Bulk Volume Fraction of Shale (fraction)

$R_{s h}$: Shale Resistivity (ohm m)

F: Formation Resistivity Factor (dimensionless)

Output(s)

$\alpha$: Clay Distribution Factor (dimensionless)

$\beta$: Clay Distribution Factor (dimensionless)

$\frac{1}{R_{o}}$: Formation Hydrocarbon Resistivity (per(ohm m))

Formula(s)

$$ \begin{gathered} \alpha=\left(\frac{V_{s h}}{R_{s h}}\right) \\ \beta=\frac{1}{F} \\ \frac{1}{R_{o}}=(\alpha)+\left(\frac{\beta}{R_{w}}\right) \end{gathered} $$

Reference(s)

Bassiouni, Z., 1994, Theory, Measurement, and Interpretation of Well Logs. SPE Textbook Series Vol. 4. Chapter 1, Page: 16.