The skeleton-relaxed model for poroviscoelastic media
黏弹双相介质中的松弛骨架模型

Based on the Biot theory,the relaxation effect of the solid skeleton is considered in porous media.We introduce the three parameters of P wave quality factor,S wave quality factor and diffusion quality factor to describe the poroviscoelastic wave equations.A pseudo-spectral method is used in wavefield forward modeling.Simulation results show that the skeleton-relaxed model not only works for the fluid saturated porous media in ultrasonic band.It can also be used for the explanation of elastic waves' high attenuation in seismic band,to approximate the solid particles' relaxation effect in a mesoscopic scale.Niche Genetic Algorithms are introduced in the inversion of 24 parameters for a three-layer model.Inversion results of the wavefield without noise hold high precision.But if white noise is added,the parameters whose true values are near singularity will get increased error.Finally,actual shot gather sections from some district in east China are processed.The solid bulk modulus,the solid density and the quality factors of the shallow layers are estimated.