Geomechanics and FracturingIn-Situ Stress and Rock Mechanics

Maximum Principal Stress in Reverse Faulting Formula

\sigma_{max}=\frac{\sigma_c(S_{hmax}-P_p)}{S_v-P_p}

Maximum Principal Stress in Reverse Faulting calculates maximum principal stress for in-situ stress and rock mechanics workflows in geomechanics and fracturing.

Calculate

How engineers use this formula

Use this formula when the listed inputs (sigma_c, S_hmax, S_v, P_p) are known and the assumptions behind the cited in-situ stress and rock mechanics relationship match the engineering case being checked.

Assumptions

Input values are representative for the well, reservoir, fluid, or equipment case being evaluated.
The declared units match the field-unit constants used in the formula.
The cited formula applies to the selected petroleum engineering workflow.

Limitations

The calculation does not replace a full engineering model or operating procedure.
Accuracy depends on the source correlation, assumptions, input quality, and unit consistency.

Common mistakes

Mixing unit systems without converting the inputs.
Using default example values as field recommendations.
Applying the formula outside the source assumptions.

Default example

Using the default inputs, sigma_max equals 10,000 psi.

sigma_cpsi

6000

S_hmaxpsi

9000

S_vpsi

7000

P_ppsi

4000

Inputs

sigma_c

psi

Least Principal Stress at Failure

S_hmax

psi

Maximum Horizontal Stress

S_v

psi

Vertical Stress

P_p

psi

Pore Pressure

Outputs

sigma_max

psi

Maximum Principal Stress

sigma_c

psi

Least Principal Stress at Failure

S_hmax

psi

Maximum Horizontal Stress

S_v

psi

Vertical Stress

P_p

psi

Pore Pressure

Source and review

reviewed

Zoback, M.D. 2007. Reservoir Geomechanics, Cambridge University Press, Page 133.

Source