Dynamic poroelasticity of thinly layered structures

Compressional seismic P!waves\ propagating in poroelastic\ ~uid saturated\ laminated sediments are strongly a}ected by the medium heterogeneity[ Here\ simple analytical expressions for the P!wave phase velocity and attenuation coe.cient are derived[ Both are functions of frequency and statistical medium parameters such as correlation lengths and variances[ The theoretical results are compared with results from numerical simulations and show good agreement[ In heterogeneous media\ impedance ~uctuations lead to poroelastic scattering ^ variations of the layer compressibilities cause inter!layer ~ow "a 0!D macroscopic local ~ow#[ From the seismic frequency range "09 099 Hz# up to ultrasonic frequencies\ attenuation due to heterogeneity is strongly enhanced compared to homogeneous Biot models[ The new theory automatically includes di}erent asymptotic approxi! mations\ such as poroelastic Backus averaging in the quasi!static and the no!~ow limit\ geometrical optics\ and intermediate frequency ranges[ 0887 Elsevier Science Ltd[ All rights reserved