Porosity dilation waves

Biot and Darcy theory shortcomings have been largely overcome by development of a coupled diffusion-dynamic formalism (de la Cruz et al. 1993, Spanos 2001, Spanos et al. 2(X)3). Porosity is treated as an explicit thermodynamic variable, so that dnumerical model development. Nevertheless, if they are solved subject to the assumption of the incompressibility of a liquid saturant, the existence of a slow wave is predicted. It is called the porosity dilation (PD) wave it is not a strain wav, it is a coupled liquid-solid displacement wave, and it has some interesting properties. 

PD wave excitation should be a highly efficient method of triggering compaction in appropriate reservoirs, and in cases where sand densification in situ is desired. This is because the porosity dilation effect causes cyclic changes in the grain-to-grain... 

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