Effects of Strain Amplitude on Relaxation Spectra of Wave Attenuation in Rock

P262 Effects of Strain Amplitude on Relaxation Spectra of Wave Attenuation in Rock E.I. Mashinskii* (Institute of Petroleum Geology and Geophysics RAS) SUMMARY The laboratory study of wave attenuation in sandstone and the “atomic” elastic solid states (quartz and duralumin) under confining pressure of 20MPa has been performed using the reflection method on pulse frequency of 1 MHz in the strain amplitude range ~ (0.3 - 2.0) * 10-6. The experiments have shown the unusual results in the behavior of the relaxation spectra of wave attenuation in dependence on strain amplitude. The attenuation nonlinearly decreases with increasing strain amplitude. In