Wave Velocities Amplitude Dependence and Hysteresis in Consolidated Rocks under Confining Pressure

P041 WAVE VELOCITIES AMPLITUDE DEPENDENCE AND HYSTERESIS IN CONSOLIDATED ROCKS UNDER CONFINING PRESSURE Abstract 1 The laboratory experiments on duraluminium quartz sandstone under confining pressure (up to 40 MPa) have shown a nonlinear dependence of wave velocities Vp and Vs on amplitude and their hysteresis. In a range of strain amplitudes 10 -7 -10 -6 modifications of waves velocities achieve 0 84 %. The possible reason of non-linearity is the micro-plasticity. Introduction Linearly elastic model of a geological medium used in seismics not adequately describes a real situation of seismic wave propagation. Linearly inelastic model has the best approximation but