An earlier model for a new mode of wave propagation in a saturated porous medium is to be extended to explore an interior singular region of focussed pressure, which is postulated to represent a local region of liquefaction (loss of solidity) of the porous medium. A mathematical model of this interior region will be developed and matched to the previously obtained exterior solution. An experimental demonstration that pressure focusing and liquefaction is possible in the new propagating wave mode is included in the investigation. The mechanism of pressure focusing in a propagating wave to produce local liquefaction has possible importance in earthquake diaqnostics and failure mechanism.
