Page 3 - sulli2000_sardinia_channel

A. Sulli / Tectonophysics 324 (2000) 321–336 323

Fig. 3. Structural map of the Sardinia Channel–Sicily Straits area constructed on the basis of the reflection seismic lines (modified
from Catalano et al., 1996): 1, main thrust fronts; 2, thrusts; 3, strike–slip faults; 4, structural axes; 5, normal faults. (a) Front of
the Apenninic–Maghrebian submerged basinal units. (b) Egadi thrust front. (c) Belice thrust front. (d ) Sciacca thrust front. STF:
Sardinia thrust front; DTF: Drepano thrust front; ETF: Egadi thrust front.

Previous studies, based mainly on seismostrati- $ the mechanism and timing of the overthrust of
graphic analysis, described the sector of the chain the Kabilian–Calabrian units and Apenninic–
developing between Sardinia and Sicily (Section 4). Maghrebian units.
Nevertheless, very little information has been avail-
able until now on deep crust and its mutual 2. Physiography
relations with the overlying chain. New deep
seismic reflection profiles (Italian CROP line The main morphological and topographic fea-
9423), together with a reinterpretation (Sulli, 1996) tures occurring in the Sardinia Channel are
of multichannel seismic lines (AGIP, OGS), pro- described here in order to illustrate the physiogra-
vided new information on the main crustal charac- phy of the study area (Fig. 2).
teristics (geometry, thickness, depth of the
Moho, etc.). In the southern sector of the study area a
widespread continental slope (from −200 to
Seismic facies analysis, calibrated by dredges, −1000 m deep) drops down from the Sicilian shelf
well and outcrop data, supported by geophysical and is linked to the western prolongation of the
data, sheds light on some open problems such as: Tyrrhenian basin, where the depth exceeds 2000 m.
$ the geometry and structural style of the crust In this borderland slope some seamounts and
basins occur. The north-western Sicily offshore, an
between southern Sardinia and north-western indented continental shelf interrupted by canyons
Sicily; related to morphodynamic and tectonic events,
$ the geometry and deformation style of the crys-
talline bodies north of the Elimi Chain (Fig. 2);