Biot／Squirt Model in Viscoelastic Porous Media

Viscoelastic wave equations are derived for both the Biot flow and squirt-flow involved.The relationship between phase velocity or attenuation of viscoelastic wave and macro parameters of the reservoir is clarified in a porous extensive dilatancy anisotropy medium.Numerical models clearly demonstrate that the viscoelastic property of rocks,not the squirt-flow,causes the dispersion and attenuation in the low-frequency range.The attenuation of the quasi SV-wave,SH-wave and the quasi P-wave depend strongly on the directions of permeabilities.Furthermore,the trends of attenuation of the quasi P-wave fast and the quasi SV-wave are inversed in both the high-frequency and low-frequency ranges.Our numerical result is in agreement with the experimental result that was carried out for the Biot/Squirt model by Jorge [Geophys.65(2000)202].