A simple method of determining ultrasonic velocities in rocks

Abstract

We have devised a simple method of determining elastic constants of rocks which is based on the principle of the critical angle method employed by Schneider and Burton. In this method a narrow beam of ultrasonic waves strikes the rock section immersed in a liquid at right angles to its axis of rotation, and the critical angles θ_d and θ_s for total reflexion of the longitudinal and transverse waves set up in the section are determined experimentally. Knowing the velocity of ultrasonic waves V in the liquid, the velocities of longitudinal and transverse velocities V_d and V_s in the rock section are determined by using the familiar relations, V_d = V/sin θ_d; V_s = V/sin θ_s.