Pore pressure of shale (Traugott)

Input(s)

z: Depth (ft)

$S_{v}$: Sonic Velocity $(\mathrm{ft} / \mathrm{s})$

$R_{o}$: Resistivity of Shale (ohm $\mathrm{ft}$ )

$R_{n}$: Expected Resistivity (ohm ft)

$\left(P_{p}\right)^{\text {hydro }}$: Hydrostatic Pore Pressure (psi)

Output(s)

$P_{p s h}$: Pore Pressure of Shale (psi)

Formula(s)

$$ \mathrm{P}_{\mathrm{psh}}=\mathrm{z} *\left(\left(\frac{\mathrm{S}_{\mathrm{v}}}{\mathrm{z}}\right)-\left(\left(\frac{\mathrm{S}_{\mathrm{v}}}{\mathrm{z}}\right)-\left(\frac{\left(\mathrm{P}_{\mathrm{p}}\right)^{\text {hydro }}}{\mathrm{z}}\right)\right) *\left(\left(\frac{\mathrm{R}_{\mathrm{o}}}{\mathrm{R}_{\mathrm{n}}}\right)^{1.2}\right)\right) $$

Reference(s)

Mark D. Zoback, Reservoir Geomechanics, Cambridge University Press, UK, Page: 47.