The 3D quasi-static displacements during and following an earthquake provide a wealth of information on the internal structure and rheological properties of the Earth. If an earthquake occurs in a region that has shallow-viscosity zones inside the crust or at the top of the mantle (asthenosphere), then post-seismic displacements of the crust on the order of millimeters per year are possible. These can be detected by means of permanent GPS stations in the years following a faulting event. In this paper we systematically study the influence of viscoelastic simulation model restrictions on co- and post-seismic deformation. Examples include stratification of the Earth model, modeling of the seismic source, influence of compressibility, effects of position and viscosities of shallow low-viscosity layers. It will be shown that some of these model restrictions or assumptions can have non-negligible influences on the simulated 3D co- and post-seismic displacements.
Vermeersen L L A, Sabadini R 1997: Geophys. J. Int., 129, 531--570.