Patent ID: 7848895

Claim:
A method of hydraulic fracturing comprising: providing an estimate of an initial stress orientation and an initial pore pressure of a reservoir having an impermeable boundary, wherein said initial stress orientation comprises two initial principal stress values S Hmax and S hmin corresponding to two orthogonal initial horizontal principal stress directions r Hmax and r hmin , respectively; providing an estimate ΔP p of a change in reservoir pore pressure relative to said initial pore pressure; computing a stress rotation angle γ relating a perturbed stress orientation to said initial stress orientation; wherein said stress rotation angle γ depends on ΔP p , a difference of two initial principal stress values given by S Hmax −S hmin , and an angle θ of said impermeable boundary relative to said orthogonal initial horizontal principal stress directions r Hmax and r hmin ; determining a fracture plane perpendicular to a least principal stress of said perturbed stress orientation based on said stress rotation angle γ; and performing hydraulic fracture in said reservoir based on an assumption that hydraulic fracture will tend to occur in said fracture plane.