Seabed and shallow morphological setting of the western Sicilian Channel

The analysis of swath bathymetric data and high-resolution seismic profiles (CHIRP), combined with information from the literature, allowed the creation of an updated map of the topography of the seabed in the western part of the Sicilian Channel. This area includes the entire Adventure Plateau, the Pantelleria Graben, and the Capo Granitola- Sciacca offshore sector between the Sicilian coast, the Graham and the Terrible banks. Positive and negative bedforms (sedimentary banks, volcanoes and mud volcanoes, pockmarks) and some erosional features were recognised and analysed in the study area. The Capo Granitola-Sciacca offshore sector is a continental shelf characterised by the presence of various sand bodies that are locally cemented and interpreted as sand ridges, dunes and remnants of dune strands or barrier lagoon systems eroded by the action of bottom currents. These bodies were probably deposited during the post-LGM sea level rise, occurred from ca. 18 kyr B.P. and 6 kyr B.P. (transgressive deposits) and during the glacial phase (lowstand deposits) occurred about 20 kyr B.P., when sea level was ca. 120- 130 m lower than today. In this area there are also several volcanic edifices, mud volcanoes and numerous pockmarks due to the presence of gas. The distribution of these bodies is controlled by the faults associated with the NNE-oriented active lithospheric structure called Capo Granitola-Sciacca Fault Zone, which crosses the entire western part of the Sicilian Channel. The northern margin of the rift-related Pantelleria Graben is punctuated by NW-oriented pockmarks, probably controlled by the faults bounding tectonic depression, where several scars and a broad landslide have been this also mapped. In addition, canyons were noted along the southern margin of the Adventure Plateau.