The peculiarities of linear wave propagation in double porous media

The features of propagation of longitudinal and transverse waves (LW and TW ) in fractured porous medium (FPM) saturated with liquid are investigated b y methods of multiphase mechanics. The mathematical model of FPM accounting for inequality of velocities and pressures of liquid in pores and fracture s, liquid mass exchange and nonstationary interaction forces is developed. Processes of monochromatic wave propagation are studied. The dispersion rel ation is obtained and the effect of model parameters on wave propagation is analysed. It is established that one transverse and three longitudinal wav es propagate in FPM saturated with liquid. The fastest LW is a deformationa l wave and the two others are filtrational. Filtrational waves attenuate mu ch stronger than deformational and transverse waves. Distinction of velocit ies and pressures in liquid in various pore systems provides an explanation for the existence of the two filtrational waves in porous medium with two different characteristic sizes of pores.