Page 1 - terraces-chap10

Mem. Descr. Carta Geol. d’It.
LVIII (2004), pp. 69-72

Submerged Depositional terraces offshore Favignana (Northwestern
Sicily)

D'ANGELO S.*, LEMBO P.*, SACCHI L.*

INTRODUCTION
Within the geological surveying in the area of the Sheet n.604 (Isole Egadi) at 1:50.000 scale, some

researches has been carried on in the continental shelf offshore of the Favignana isle by means of
acoustic surveys and seismic reflection prospecting completed with investigations by R.O.V. (Remote
Operated Vehicle) and bottom sampling by grab (DEL BONO et alii 1991).

The collected data have been acquired from September 1989 to June 1993 during some surveys with
the Ammiraglio Magnaghi vessel of the Italian Hydrographic Institute (I.I.M.) and the Minerva and
Urania vessels of the National Research Council (C.N.R.).

For the high resolution seismic prospecting it has been utilized a 300 Joule UNIBOOM source; a
total 300 km of profiles were acquired in the area of the Sheet to characterized the sea floor and near
surface sediments of the continental shelf and to classify the main characters of the acoustic facies.

Fig. 1- Location map of the studies area.

GEOLOGICAL FRAMEWORK
Fig. 2- Geological sketch of the sea floor in front of Favignana Isle.
The examined area (Fig.1), located westward of Trapani on the Western Sicilian offshore, is formed

by a continental shelf built up on a rocky tectonized substrate, strongly eroded by marine erosion.
Recent sedimentary deposits are almost exclusively made of organic fragments.

The structural configuration is characterized by a series of tectonic units overthrusted eastward and
southeastward on the Iblean foreland during Miocene age. New compressive movements (reserve
faults, tectonic inversion) occur during Pliocene (CATALANO & D'ARGENIO, 1982; CATALANO et alii,
1985; CATALANO et alii, 1988).

* Servizio CARG Rilevamento geologico e analisi di laboratorio, APAT - Roma