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1 The Sicily Channel - Tunisia Plateau

1.1 Geographic limits of the Sicily Channel- Tunisia Plateau
(Central Mediterranean)

The Sicily Channel has no universally accepted definition as well as shared names (i.e.
Sicilian Channel, Sicilian Strait, Sicilian Narrow), it cover a great part of the Central
Mediterranean being bounded by the Sicily island to the north, by the Tunisia-Sardinia
Channel to the west, by Tunisia coasts to the south-west, Libyan coast to the south and
Ionian sea to the east. Thus it corresponds to the westernmost part of the subarea 2.2 of the
FAO area 37. The very complex topography and circulation patterns of the Sicily Channel
make it a highly productive area and a biodiversity hotspot, moreover it play a fundamental
role connecting the eastern and western Mediterranean sub-basins.

As the ecosystem features of the area largely depend from the physical and biological
processes of the neighbouring regions, namely Tunisia-Sardinia Channel and Ionian sea, in
this review the term Sicily Channel-Tunisia Plateau (hereafter Sicily Channel or Sicilian
Channel) has been arbitrarily used to indicate the wide area bounded by shallow bottom
features on the west, defined by the general term Western Sill (mainly Skerki bank,
Adventure bank and related banks) and, on the east, by the steep slope of Medina-Malta
Escarpment, by the Medina bank (Eastern Sill) and, from there to Misratah Cape by the 1000
m bathymetry (Fig. 1).

The Sicily strait (or strait of Sicily) has been use in order to indicate the Western Sill area
and, in particular the narrow passage (about 90 nm wide) between Cape Bon (Tunisia
mainland) and Cape Lilibeo (or Cape Boeo, near Marsala, Sicily island).
The Sicily Channel encompasses other features, which have been quoted in this review such
as Pantelleria, Lampedusa, Linosa islands (Italy) and Kerkennah, Djerba islands (Tunisia),
Gela basin, the Maltese archipelago, the Malta plateau (or Hyblean plateau), the Malta
Channel, the Misratah valley (canyon), and on the Tunisia shelf, the Gulf of Hammamet and
the Gulf of Gabes (Fig. 1).

Three main rift structures characterize the central area of the Sicily Channel, Pantelleria,
Malta and Linosa grabens (basins, trough) as elongated depressions with NW-SE trending
axes. These basins split into secondary grabens such as Malta-Medina and Medina-Melita
grabens separating respectively the Maltese plateau from the Medina bank and Medina bank
from the Melita bank (Fig. 1).

Many of the known as well as some unnamed (but rising more than 100m from the sea

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