Fracture Gradient Calculator

Calculate formation fracture gradient and mud weight window

Formation Parameters

Enter depth and pressure data

Typical: 18-20 ppg for deepwater, 19-21 ppg onshore

Shale: 0.25-0.35, Sand: 0.20-0.30

Typical Fracture Gradients

  • Shallow (<5000 ft): 12-14 ppg
  • Medium (5000-12000 ft): 14-17 ppg
  • Deep (>12000 ft): 16-19 ppg

Fracture Gradient Results

Enter parameters and click Calculate

Formula Reference

Eaton Method

Fg = (v / (1-v)) x (Ob - Pp) + Pp Where: Fg = Fracture gradient (psi/ft or ppg) v = Poisson's ratio Ob = Overburden gradient Pp = Pore pressure gradient

Hubbert-Willis Method

Fg = (1/3) x (Ob - Pp) + Pp [Minimum stress] Fg = (1/2) x (Ob - Pp) + Pp [Maximum stress]

From LOT Data

Fg = (LOT_pressure + Hydrostatic) / (0.052 x TVD) Hydrostatic = MW x 0.052 x TVD