Wave Reflection from the Free Boundary of Porous-Elastic Liquid-Saturated Half-Space

On the basis of Biot's theory, predicting the existence of three types of bulk waves in a porous-elastic fluid-saturated medium, the analysis of bulk wave reflection from the free boundary is conducted. The energy distribution of the incident wave between the reflected waves is found. The qualitative distinctions between energy reflection coefficients of slow longitudinal wave from the free boundaries with open and closed pores are discovered. For vertical components of period-average power flow vector the energy superposition principle occurs valid. This principle states that energy of the incident wave is equal to that of the reflected waves. There is no energy transfer by inhomogeneous waves deep into medium. However, the energy superposition principle is not correct along the boundary of the half-space.