Coastal structure, sea-level changes and vertical motion of the land in the Mediterranean

Abstract

The Mediterranean basin is an important area of the Earth for studying the interplay between geodynamic processes and landscape evolution affected by tectonic, glacio-hydro-isostatic and eustatic factors. We focus on determining vertical deformations and relative sea-level change of the coastal zone utilizing geological, archaeological, historical and instrumental data, and modelling. For deformation determinations on recent decadal to centennial time scales, seismic strain analysis based on about 6000 focal mechanisms, surface deformation analysis based on some 850 continuous GPS stations, and 57 tide gauge records were used. Utilizing data from tectonically stable areas, reference surfaces were established to separate tectonic and climate (eustatic) signals throughout the basin for the last 20 000 years. Predominant Holocene subsidence (west coast of Italy, northern Adriatic sea, most of Greece and Turkey are areas at risk of flooding owing to relative sea-level rise), uplift (local areas in southwestern Italy and southern Greece) or stability (northwestern and central western Mediterranean and Levant area) were determined. Superimposed on the long trends, the coasts are also impacted by sudden extreme events such as recurring large storms and numerous, but unpredictable tsunamis caused by the high seismicity of parts of the basins.