A Simple Sonic Mapping Method Verified by CT Scan Images

Abstract

This study presents a novel sonic mapping method applied to coal samples, verified by CT scan imaging. Cubic coal samples with side lengths of 50-70 mm were subjected to non-destructive sonic tests, measuring both P-wave (Vp) and S-wave (Vs) velocities. Each of the three orthogonal directions (X, Y, and Z) of the cube was divided into 9 regions, resulting in 27 Vp and 27 Vs measurements per sample. From these data, 2D sonic maps were constructed for each direction, and interpolation was employed to refine the mappings. A 3D sonic map was then generated by averaging the 2D maps. The 3D sonic mapping results were compared and validated against high-resolution CT scan images, confirming the reliability of this approach for mapping the internal structure of coal samples.