Fracture pressure (Hubert and Willis)

Input(s)

$S_{\nu}$: Vertical Stress (psi)

$P_{p}$: Pore Pressure (psi)

Output(s)

$S_{\text {hmin }}$: Fracture Pressure $(\mathrm{psi})$

Formula(s)

$$ \begin{gathered} \mathrm{S}_{\mathrm{hmin}}=0.3 *\left(\mathrm{~S}_{\mathrm{v}}-\mathrm{P}_{\mathrm{p}}\right)+\mathrm{P}_{\mathrm{p}} \\ \frac{\sigma_{h \min }}{\sigma_{v}}=0.3 \end{gathered} $$

Notes: Fracture Pressure Is assumed to be Equal to Minimum Horizontal Stress.

Reference(s)

Mark D. Zoback, Reservoir Geomechanics, Cambridge University Press, UK, Page: 281.