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Abstract

In this PhD thesis, the study of the interaction between sedimentary processes and morphological
characteristics of the seabed in the Archipelago of the Egadi Islands one of the archipelagos of the
Mediterranean Sea , located in the north-west Sicily. has been carried out.
The archipelago of the Egadi Islands is part of the north-western Sicilian offshore and belongs to
the mountain range that connects the Sicilian-Maghrebian chain to Tunisia. The Marettimo
Channel, the northern extension of the Mazara channel, separates the archipelago of the Egadi into
two parts ; it is considered an important pathway for the exchange between the major water masses
of the western and eastern Mediterranean and those of southern Tyrrhenian Sea and the Strait of
Sicily.
The study was conducted through the analysis of low-frequency ultrasound findings and side-scan
sonar images, processing and interpretation of morpho-bathymetric data and the analysis of seismic
reflection profiles supplemented by seafloor samples and underwater video.
The data used for the study of the Egadi Islands, were collected as part of research projects carried
out by the Department of Earth Science and the Sea, University of Palermo (CARG, GebecSud), in
collaboration with the ISPRA, CNR-IAMC, NATO-SACLANT. The data collected were organized
and managed through the use of a geographic information system.
The objectives of this PhD thesis were: the definition of the geomorphological and sedimentological
framework of the Egadi Islands; the reconstruction of the sedimentary dynamics of the seabed of
the Egadi Islands, the analysis of the sedimentary dynamics of the seabed of the Egadi offshore; the
morpho-sedimentary reconstruction of the Egadi Islands offshore in the Late Quaternary.
The morpho-bathymetric and sedimentologic study of the Egadi offshore, confirm that the area is
affected by the presence of numerous structures, which are the expression of morpho-sedimentary
processes linked with its position within the Mediterranean Sea.
The morpho-bathymetric analysis performed along the Egadi Islands offshore, has allowed the
identification of a shelf-slope system, characterized by two distinct areas separated by a narrow
depression: the Marettimo Channel. The Egadi Islands are characterized by a continental shelf with
a gradient of 0.600 - 0.900 and a shelf break located at a depth of about 110-130 m; it has a very
complex morphology and well-preserved due to the reduced sedimentary. In the Egadi continental
slope, several morphological features are recognized tha tproduce a complex physiographic setting
in particular. along the continental slope of the Egadi Islands numerous landslides due to
gravitational movements and gullies are present. This seafloorinstability seems to be related to the
action of strong currents in the area. The Marettimo channel, in fact, is the northern extension of the
the Mazara channel that plays an important role in the exchange of major water masses.

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