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Paleogeographic evolution from the Late Triassic to the Eocene
in Sicily offshore

Giuseppe Miuccio*1 & Alfredo Frixa2
1 ENI Agip/DIGE-GELG Geological dept., Distretto di Gela,
Strada Provinciale 82, 93012 Gela (CL), Italy (E-mail: giuseppe.miuccio@agip.it)

2ENI Agip/LABO-PETR Petrographic-Sedimentological dept.,
via Maritano 26, 20097 S.Donato Mil. (MI), Italy (E-mail: alfredo.frixa@agip.it)

ABSTRACT: The Liassic-Triassic carbonate platform has been the hydrocarbon target of many
wells drilled in the Sicily Channel over the last decades. The Late Triassic sediments are
currently the deepest horizon reached in this sector of the African foreland.
The stratigraphic and petrographic studies carried out on these wells and on those drilled in the
foreland of onshore Sicily have led to the reconstruction of the palaeographic evolution of the
examined area (Fig. 1).

Fig. 1. Index map.

Like the succession which outcrops onshore, the Triassic-Eocene interval drilled in the Western
Sicily offshore belongs to the African domain. This interval shows progressive sinking of the
carbonate platform at the end of the Middle Liassic, with sea-mount conditions passing upwards
to epibathyal ones.
The following differences can be observed in the depositional environment towards the
boundaries of the studied area:
- To the south-east, during Malm, sea mount conditions (ANTONELLI et alii, 1988),

corresponding to the Sicilian Rosso Ammonitico Fm., were established on the oldest shallow
carbonate deposits.
- In the central area of the Sicily offshore, towards Tunisia, Dogger-Hauterivian p.p. layers are
absent or discontinuous. This leads to the belief that there were periods of non-deposition or
emersion.
The area sunk at the end of the Hauterivian; during the Early Cretaceous basinal, partly
carbonate and partly terrigenous, sediments of the Sidi Kralif and Fahdene Formations, were
deposited.
- To the south, in the Pelagian sector, the lack of sedimentation is limited to the Late Jurassic;
the sinking occurred during the Neocomian.
During the Middle-Late Eocene once again a carbonate platform environment estasblished
(Halk-El-Menzel Fm.; BISMUTH & BONNEFOUS, 1981).

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