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We processed data from~100 continuous GPS stations to provide new insights into the crustal motion and deformation of central and western Greece. We used the derived velocity field to evaluate two-dimensional strain and rotation rate tensors, and we mapped the dilatation and maximum shear strain rates. In central Peloponnese and Epirus, we documented a 90°switch in the extension direction, which can be explained on the basis of the plate boundary configuration. Evidence for an extended deformation pattern in central Greece was found. Additionally, we detected two pairs of shear belts, one in Akarnania-NW Peloponnese and one in North Aegean. We delineated two rotational domains that dominate the present-day pattern. Moreover, we saw no geodetic evidence for North Anatolian Fault growth toward central Greece. We translated the geodetic strain rates into rates of seismic moment release and compared them with earthquake catalog-based moment rates. In the central Ionian Sea, the geodetic strain is completely released seismically, which is indicative of a fully coupled seismogenic zone. However, for most of the study area, the geodesy-based moment rates are at least 2 times higher than the earthquake-based rates. We attribute this mainly to earthquake catalog representativity over the long-term situation. However, for the Gulf of Corinth, it is unrealistic to associate the high ratio of geodetic to seismic moment rates only to incompleteness of the earthquake catalog; instead, long-term aseismic deformation must be an important mechanism accommodating a considerable portion of the strain budget, especially at its western part.

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Earthquake shaking can trigger a large number of landslides in hilly or mountainous areas, considerably aggravating the impact of the seismic event in terms of overall damage and loss of life. Thus, the delineation of slope areas that have a significant probability of failing under future seismic action appears imperative for disaster mitigation. In the present study, we follow a time probabilistic approach for the evaluation of earthquake-induced landslide hazard in Greece through the estimation of the minimum resistance required for slopes to remain within a prefixed value of exceedance probability of failure. Taking into account the characteristics of seismicity affecting Greece, we constructed maps representing the spatial distribution of critical acceleration values that imply a 10% probability that Newmark's displacement will exceed significant thresholds in a time interval of 50 years. These maps provide the spatial distribution of the strength demand required for slopes to resist failures under the action of the regional seismicity. Such maps allow an assessment of whether particular slopes have a significant failure probability by comparing the strength demand estimated at the location of the slope with its actual critical acceleration calculated from slope material properties and slope angle. To exemplify the possible use of these strength demand maps in local hazard estimates, we compare, within a GIS framework, the critical acceleration values obtained by the application of the time probabilistic approach with actual in situ critical acceleration values for a coastal area of the Western Gulf of Corinth.