Simple Models of the Deformation of an Earth with a Fluid Core-I

It is shown that difficulties encountered with matching the motion of a fluid core to the static deformation of an elastic mantle can be reproduced in a very simplified model. The problem is one of singular perturbation, and can be simply resolved by solving the time dependent problem and recognizing that the limit of frequency going to zero is not one that can be taken without consideration of real fluids, that is fluids with dissipation. Effects of rotation are shown to make qualitative changes in the limit process.