Formation factor (Archie's equation with resistivity logs)

Input(s)

$\mathrm{T}$: Tortuosity (unitless)

$\Phi$: Porosity (fraction)

Output(s)

F: Archie (unitless)

Formula(s)

$$ F=\frac{T}{\Phi} $$

Reference(s)

Ellis, D.V., Singer, J.M. 2008. Well Logging for Earth Scientists. Second Edition. Springer. Chapter: 4, Page: 76.