An experimental research of the defect accumulation under uniaxial loading of a natural heterogeneous material is carried out in this work. Defect formation process has been controlled using two non-destructive techniques (methods) such as acoustic emission (AE) and X-ray computed microtomography (CT). The combined use of these methods made it possible to find out correspondence between energy characteristics of AE accompanying the defect formation and the volume of these defects. It was found that total defect volume is lineary dependent on total AE signal energy. This fact corresponds to previously discovered phenomenological relationships for the sources of tectonic earthquakes. Mean defect size has been estimated based on obtained linear dependence. It was shown that mean linear size of defect does not exceed 100μm regardless of the assumptions about the defect shape.

Accumulation of defects in the synthetic quartz single crystal has been investigated at the early stages of deformation. Process is studied with the help of three independent nondestructive methods, namely: acoustic emission, X-ray computed tomography and synchrotron radiation topography. It is shown that results obtained by the three methods are consistent with each other, allow detecting the area of defect formation and, what is more important, to match acoustic emission parameters with the ones of defects. This result is of practical importance, since it makes it possible to further identify areas of fracture growth and estimate their size in situ only by analyzing acoustic emission data in cases where the use of other control methods is impossible.