  We formulate the the generalized Forchheimer equations for the
three-dimensional fluid flows in rotating porous media. By implicitly solving
the momentum in terms of the pressure's gradient, we derive a degenerate
parabolic equation for the density in the case of slightly compressible fluids
and study its corresponding initial, boundary value problem. We investigate the
nonlinear structure of the parabolic equation. The maximum principle is proved
and used to obtain the maximum estimates for the solution. Various estimates
are established for the solution's gradient, in the Lebesgue norms of any
order, in terms of the initial and boundary data. All estimates contain
explicit dependence on key physical parameters including the angular speed.
