4. Station displacement

摘要

In this chapter an overview of phenomena causing station displacements is given. Conventional models dealing with crust deformation are described in the IERS Conventions. The recent version 2010 (Petit and Luzum, 2010) recommends corrections of station catalogue coordinates for the effect of solid Earth tides and loading due to ocean tides, atmospheric tides, pole tide, and ocean pole tide. The corrected station coordinates are used then as a priori instantaneous positions into the adjustment of observational data. The influence of single events on the vertical displacement is shown in Figure 4.1 whereas deformation in the horizontal plane is typically nearly one order of magnitude smaller. The displacement caused by non-tidal atmospheric loading and hydrology loading (two bars on the right-hand side in the Figure 4.1) are not included in the recommendations of the IERS Conventions. Nevertheless it is stated in the document that some recommended models to correct the crustal displacement caused by these non-tidal effects are envisioned for the next edition of the IERS Conventions.