Magic Sheet 26 Ustica — Map (OpenData)

The sheet includes the island of Ustica, located in the continental escarpment of the northern-Sicilian margin, between the basin of the southern Tyrrhenian Sea and the Sicilian-maghrebide chain. Foglio Ustica occupies a sector of the continental escarpment of the northern-Sicilian margin, in the transition zone between the southern Tyrrhenian basin and the Sicilian-maghrebide chain. It is entirely occupied by a subsea volcanic apparatus of quaternary age, of elliptical shape, oriented about SO-NE, which rises from a depth of 2 500 m. The elements of potential hazard recognised in the area have been grouped into three different types: underwater volcanic buildings; landslide areas and their deposits, areas with widespread erosion, which develop due to the high slopes of the escarpment; regional tectonic structures, such as the submarine extension of the Arso system, recognised on the ground and well correlated with that in offshore. The northern offshore of Ustica is characterised by the presence of numerous volcanic buildings, some of which align with the main tectonic features. In the southern offshore, the high acclivity of the escarpment predisposes the seabed to phenomena of gravitative failure at various depths, both in the form of landslides and “spread erosion”. In this sector the edge of the platform shows a very articulated trend and in some cases the platform is absent due to phenomena of backwardness. There are 5 critical points (tectonic line, landslide, diffuse erosion area, eruptive cone). CoNISMa-UniPalermo