Modelling effective rheologies for viscoelastic porous media with application to silt, and. medium and coarse sand

Abstract

A modification of Biot's pornelastic differential equi~tionsis made to include nrarrix-fluid

interaction mech~ismsw hich assume n solid-fluid relaxation hnction coiipli~igc c~eflicient.

Vulucs of physical propcrtics of scdi~iicntsn .rc incorporuted'into cqilationswhicl~d cfinc phnsc

yelocity nnd attei~uatibnf or pcirous media which are dependent on the co~~posidteen sities of

various medin (silt, and lnediu~na nd coqfse sand). The results enable us to coinpare tlie

.atenuation and velocities of,waves in these media. We observed that the densityof coarse'

snnd is greatei than that df medium sand md this in t.um is greater thmi that of silt--the sariie

holds-for the velocities of P-waves in these media but the situation is converse Ibr shear waves

in the same given nedia. As the densities ofthe media increhse, their attenuation decreases as

it w;rs found that the uttenualion of silt is the highest aod that of coarse sand lowest for the

media considered. ' -