oa Peculiarity of elastic characteristics of sedimentary SiO2, zeolite, foam polystyrene

The most pronounced types of acoustic symmetry are found in sandstones SiO2, but in limestone CaCO3 samples exhibit the least pronounced symmetry type and the lowest value of the integral anisotropy coefficient Aμ. The highest values of phase velocities V and elastic constants Cijkl were found. The measuring of internal friction background in sedimentary SiO2 after mechanical, heat treatments gives information about the changing of defect nanostructure and the thermoelastic strains fields. The broadening of internal friction maximum represents the relaxation process of structural defects new types.