GMI-Jizba-E (Jizba, 1991)

UCS = 3668 e(e´ 4.14e ^{– 7})

where:

3668 is in psi.

3.65 is in 1/psi.

E is static Young modulus.

The equation is based on test data from Travis Peak shaley sandstones analyzed by Jizba (Stanford PhD thesis, 1991). The sample data was derived from low to medium porosity, low permeability, consolidated sandstones (1% < phi < 18%). E in this formula is calculated from static measurements and therefore, the applicability of the equation is limited to tight sandstones with E_static » E_dynamic, or with known dynamic-static correction factor. The measurements were carried out on dry samples and therefore, corrections to the value of E for fluid compliance effects are required in fluid-saturated sandstones.