On the analysis of monument stability in GPS RAP stations using PPP time series

The study of the stability of GPS stations and its monuments is an important aspect to improve the analysis of geodynamical features and tectonic movements in active areas. In this study we present the first results of seasonal dilatation and white noise values of 6 GPS stations of the RAP network based on four years of continuous un-differenced PPP position time series, processed by GIPSY-OASIS software. In addition, to obtain the trend and periodicity amplitude the time series analysis software CATS was used. The preliminary results show an influence of the situation, height of the building and surrounding obstacles of each station, with +/- 2 mm of white noise estimated. Stations situated in high buildings show prominent seasonal periodicity with +/- 6 mm amplitude. On the other hand, stations built over the surface or made of concrete have better velocity estimation and less periodicity impact. Furthermore, this study show a preliminary classification of the stations using parameters derived from seasonal periodicities and white noise.