  In this paper we study the spatial and temporal behaviour of the dynamic
processes in porous elastic mixtures. For the spatial behaviour we use the
time-weighted surface power function method in order to obtain a more precisely
determination of the domain of influence and we establish spatial decay
estimates of Saint-Venant type with time-independent decay rate for the inside
of the domain of influence. For the asymptotic temporal behaviour we use the
Cesaro means associated with the kinetic and strain energies and establish the
asymptotic equipartition of the total energy.
  A uniqueness theorem is proved for finite and infinite bodies and we note
that it is free of any kind of a priori assumptions of the solutions at
infinity.
