GPS-derived estimates of crustal deformation in the central and north Ionian Sea, Greece: 3-yr results from NOANET continuous network data

Ionian Sea (western Greece) is a plate-boundary region of high seismicity and complex tectonics, dominated by frequent earthquake activity along the right-lateral Cephalonia transform fault. We present an analysis of 30-s GPS data from five (5) continuous stations of NOANET (NOA permanent GPS network) spanning the period 2007–2010. Our results show N-S crustal shortening onshore Lefkada island of the order of 2–3 mm/yr which is probably related to increased locking on the offshore Lefkada fault. We also calculated a large difference (1:3) in the principal strain rate amplitude between extension and shortening for the central Ionian Sea.

► We examine strain patterns from GPS measurements in the Ionian Sea, Greece. ► We process 30-s data from five (5) continuous stations of NOANET (NOA permanent GPS network) spanning the period 2007–2010. ► Our results show N-S crustal shortening onshore Lefkada island of the order of 2–3 mm/yr which is probably related to increased locking on the offshore Lefkada fault. ► We also calculated a large difference (1:3) in the principal strain rate amplitude between extension and shortening for the central Ionian Sea.