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390 Facies (2007) 53:389–400

Fig. 1 Tectonic sketch of the
central Mediterranean area (after
Catalano et al. 1995). 1 Corso-
Sarde block. 2 Kabylo-Pelorita-
nian Unit. 3 Apennine-Maghre-
bian Unit and deformed
foreland. 4 Foreland and less de-
formed foreland (Tunisia, Iblean
Platform). 5 Plio-Quaternary
volcanism. 6 Arrow indicates the
position of Marettimo Island and
hence of the Egadi Archipelago

(e.g. extensional faulting, volcanic activity, crustal thin- Panormide domain with evaporite deposits (Di Stefano
ning) correlated with the development of the Tyrrhenian et al. 1997).
Basin (Elter et al. 2003). The main cause is attributed to
the anticlockwise rotation of the Corso-Sarde block and The Upper Triassic succession of Punta Bassano has
its successive collision with the North African margin been deposited on the inner part of the Panormide platform
(Catalano et al. 1995). In the Egadi thrust belt, the present (Abate et al. 1999).
ramp-Xat duplex geometry results from the detachment of
the sedimentary cover. Marettimo Island is considered a single structural ele-
ment formed by four tectonic units settled during the Late
The western Mediterranean palaeogeographic recon- Miocene to Pliocene. They are, from NW to SE and from
structions for the Triassic period (StampXi and Borel 2004, lower to upper: the Punta Bombarda, the Punta Troia-
with bibliography) generally show a crustal thinning of Marettimo, the Monte Falcone and the Punta Bassano units
North Africa in relation to the Neo-Tethyan opening. The (Abate et al. 1982, 1995, 1996) (Fig. 2).
highly rifted nature of the Mesozoic African continental
margin during the Tethyan spreading and its compartmen- The sedimentological and biostratigraphic analyses of
talisation into a number of sub-basins, brought about depo- the Upper Triassic succession of Marettimo Island is based
sition in foredeep settings that remained deep marine on the study of a geological section located on the Punta
through much of the early Middle Miocene. Bassano promontory in the south of Marettimo Island at an
altitude of about 120 m. Here, the Middle? to Upper Trias-
From the Triassic up to the Tertiary (Paleogene), three sic shallow-water carbonate platform deposits of the Punta
main palaeogeographic domains have been recognised in Bassano unit crop out in a recumbent northwest-verging
western Sicily: the pelagic Imerese-Sicani domain with anticline, which tectonically overlaps the Punta Troia-
basinal deposits, the neritic Hyblei-Saccense domain char- Marettimo Unit (Fig. 2).
acterised by carbonate platform deposits and the neritic
While a few previous studies have focused on geology,
lithostratigraphy and macropalaeontology (Jacobacci 1955;

Fig. 2 Schematic NW/SE tectonic cross section of the Marettimo Island (after Abate et al. 1982)

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