Enhanced velocity tomography: Practical method of combining velocity and attenuation parameters

Acoustic (ultrasonic) tomography is now a well acepted method for investigating the internal structure of rock samples and rock masses. In this article we describe a new parameter to be imaged, which combines the robustness of velocity tomography and the sensitivity of attenuation tomography resulting in Enhanced Velocity Tomography. The theoretical considerations are illustrated by a computer simulation and then by application to data from a granite sample subjected to induced damage by heating. In both cases the Enhanced Velocity Tomography is found to be more sensitive to the internal rock structure than classical velocity tomography and overcomes instability problems characteristic of attenuation tomography.