Internal Structure Research of Shungite by Broadband Ultrasonic Spectroscopy

Abstract

The internal structure of plane-parallel plates of shungite is studied. The broadband ultrasonic pulses are used to measure the velocities of longitudinal and shear elastic ultrasonic waves. The accuracy of measurements is 0.3% in the case of longitudinal wave velocity and 0.5% in the case of shear wave velocity (scanning pitch over the surface of specimens was 0.5 mm). Local elastic moduli of shungite (Young modulus, shear modulus and Poisson's ratio) are uniquely determined from the velocities of elastic waves.