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2 Topography and Bathymetry

The Sicily Channel is an area where the moving water strongly interacts with the ocean floor,
thus topography and bathymetry both influence the flow of water and has direct implications
on the bottom substrate characteristics, on aquatic habitats and distribution of fish
populations.

The Sicily Channel connects the western and eastern Mediterranean sub-basins and is
characterised by a complex bathymetry with wide continental shelves, deep and shallow
channels as well as wide abyssal plains. It plays a crucial role in the passage of the
superficial and intermediate water masses in transit between the eastern and the western
Mediterranean sub-basins and also prevents the direct mixing of the water masses from the
deep and bottom layers of the two sub-basins.

The complex topography and bathymetry of the Sicilian Channel is the result tectonic and
magmatic processes, which mark the offshore continuation of the accretionary prism of Sicily
(Corti et al., 2006), where a NW-trending rift system crosscuts the Apennines-Maghrebides
belt.

Carminati et al. (2010) summarize the processes as:

1. Pliocene–Pleistocene NW-dipping foreland monocline generating the overlying
foredeep (Mariotti and Doglioni, 2000);

2. Roughly ENE-WSW to E-W-trending thin-skinned imbricate wedge, progressively
emplaced from the Early-Middle Miocene to Present (e.g., Roure et al., 1990a;
Catalano et al., 1996);

3. NW-trending normal faults and related grabens or half grabens, associated with a
Pliocene-Recent rifting phase that led to the development of the Sicily Channel.

Toward the northwest, the Sicily Channel rift seems to be connected with the Campidano
graben, in southwest Sardinia, and affects also the Pelagian shelf, onshore Tunisia and it
continues to the southeast into the Sirte basin in Libya (Corti et al., 2006).

This Sicilian Channel comprises two sill systems separated by an internal deep basin. The
Eastern Sill system is divided in the Malta plateau and Medina-Melita banks and it has
maximum depth of about 540 m and connects the Sicilian Channel with the Ionian Basin. The
Western Sill is divided in several banks among which the larger is the Adventure bank.
Narrow shelf separates these large sill systems in the central part; here the shape of the
slope is extremely irregular, incised by many canyons, trenches and steep slopes.

The eastern sill system is characterized by some extensive, shallow, generally flat-topped or

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