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A. Sulli / Tectonophysics 324 (2000) 321–336 325

Fig. 4. Grid zone C and G seismic reflection lines of Minister of Industry of Italy and of CROP line and location map of dredge
hauls (modified from Antonelli et al., 1991) and some commercial borehole drills. Dredge symbols: A, Quaternary–Upper Miocene
rocks and volcanics; B, Lower Miocene–Oligocene flysches; C, Eocene–Upper Jurassic deep marine carbonates; D, Liassic shallow
platform carbonates; E, Upper Triassic deep marine shales and carbonates; F, Hercynian-type crystalline rocks.

account the chronostratigraphic scheme of the Colombi et al., 1973) where Recent magmatic
depositional sequences of the Plio-Pleistocene bodies ( Ustica to Aceste volcanic complexes), and
marine record of the central Mediterranean crystalline rocks of the Sardinian and Kabilian–
(Catalano et al., 1998b). Calabrian units, as well as the thinned continental
crust, give higher anomalies. Low heat flow values
4. Previously available data are known from the southern Sardinia Channel,
whilst the northern zone is characterized by higher
4.1. Geophysics heat flow (Della Vedova et al., 1984; Hutchinson
et al., 1985). The low-frequency magnetic anoma-
Geophysical data, collected in the past by sev- lies in the Elimi chain (AGIP, 1981) could be
eral authors, has provided some information on related to a shallow basement (4–5 km), as well
the crustal characteristics of the Sardinia Channel. as to discontinuities of the structural framework
Seismic refraction data (Steinmetz et al., 1983; ( Terdich, 1984).
Recq et al., 1984; Duschenes et al., 1986; Rehault
et al., 1987) point out that the depth of the Moho 4.2. Structural setting and stratigraphy
increases from 10 km in the Tyrrhenian basin, to
30–35 km towards Sardinia and Sicily. In the study area ( Figs. 3 and 6) the most
elevated portions of the tectonic stack (Sardinian
Gravity anomalies are fairly high over the whole units) override the Kabilian–Calabrian units
Sardinia Channel (Morelli and Finetti, 1973; (Barbieri et al., 1984) in the Cornaglia area