First GPS measurements across the Central-Western Mediterranean area

This paper concerns the displacement field of the central-western part of the Mediterranean basin estimated by the analysis of three repeated GPS surveys (1995, 1996 and 1997) consisting of 8 sites of a network. This network includes for the first time the stations of Algiers and Arzew, located in Northern Algeria, an area not yet investigated by regional GPS surveys. Lampedusa station is located in the Sicily Straits rifting area while the other five stations of Cagliari, Wettzell, Madrid, Matera and Noto belong to the IGS permanent tracking network. The statistical analysis of 1995, 1996 and 1997 data show significant displacements at five stations. The displacement vectors of the African sites show a convergence between the African and the Eurasian plates at a rate of 0.8 ± 0.4 cm within a two year time span. A comparison between the displacements estimated in the present work and the ITRF96 determinations for the five permanent stations allow us to evaluate the motion of Lampedusa, Algiers and Arzew in the IERS Terrestrial Reference System