Rotation of maximum principal stress near wellbore
Input(s)
A: Stress Field Direction (dimensionless)
\(\mathrm{P}_{\mathrm{p}}\): Change in Pore Pressure \((\mathrm{psi})\)
\(\theta\): Fault Orientation (degrees)
\(\mathrm{S}_{\mathrm{hmax}}\): Maximum Principle Stress (psi)
\(\mathrm{S}_{\mathrm{hmin}}\): Minimum Principle Stress (psi)
Output(s)
\(\gamma\): Rotation (degrees)
Formula(s)
\[
\gamma=0.5 * \operatorname{atan}\left(\frac{\mathrm{A} * \mathrm{P}_{\mathrm{p}} * \sin (2 * \theta)}{\mathrm{S}_{\mathrm{hmax}}-\mathrm{S}_{\mathrm{hmin}}+\mathrm{A} * \mathrm{P}_{\mathrm{p}} * \cos (2 * \theta)}\right)
\]
Reference(s)
Mark D. Zoback, Reservoir Geomechanics, Cambridge University Press, UK, Page: 393.