GPS surveys in the foreland-foredeep tectonic system of Southeastern Sicily:first results

The Hyblean plateau (Southeastern Sicily)is characterised by three main tectonic structural trends: the first, NNW-SSE striking,runs on the eastern most part of the plateau and is linked to the Hyblean-Maltese fault system; the second runs along the western part of the plateau with a NNE-SSW direction and is characterised by a sinistral strike slip motion,like the Scicli fault;the third ENE-WSW striking, characterises the northernmost part of the area,including the Scordia-Lentini graben.We analysed GPS data collected in a dense network located in the northern area of the Hyblean plateau during 1998 and 2000, between the towns of Catania and Syracuse. Data from Noto,Matera and Cagliari IGS stations,were included in the processing to connect this network to the International Terrestrial Reference Frame (ITRF).The comparison between 1998 and 2000 data sets shows an average northward motion of the GPS stations located south of the Gela-Catania foredeep.Site velocities decrease from south to north and show a weak internal deformation of the northernmost part of the Hyblean plateau.