Formula 11.14
Fracture gradient (Eaton)
Input(s)
v: Poisson (dimensionless)
$S_{v}$: Vertical Stress (psi)
$P_{p}$: Pore Pressure (psi)
Output(s)
$S_{\text {hmin }}$: Minimum Horizontal Stress (psi)
Formula(s)
$$ \mathrm{S}_{\mathrm{hmin}}=\left(\frac{\mathrm{v}}{1-\mathrm{v}}\right) *\left(\mathrm{~S}_{\mathrm{v}}-\mathrm{P}_{\mathrm{p}}\right)+\mathrm{P}_{\mathrm{p}} $$
Reference(s)
Mark D. Zoback, Reservoir Geomechanics, Cambridge University Press, UK, Page: 282.