GMI-Teikoku-Vp

UCS= 167185 e^(–0.037Dt)

where:

167185 is in psi.

Dt is in ft/μs.

This equation is derived from the correlation of triaxial test results on eight volcanic core samples with acoustic logs in a well in northwest Japan. The core density ranges between 2.4 and 2.6 g/cm³. The reported UCS ranges between 8,000 and 18,500 psi.