Page 5 - Frixa_Miuccio_Paleog-evolution_EAGE

In the northernmost part, up to the present shoreline, the sinking of the platform occurred at the
end of the Toarcian and sea-mount areas set up. The sea-mount lasted up to the end of the Malm
(Rosso Ammonitico Fm.) and gradually extended to other marginal, initially emerged areas. To
the west of the Egadi islands the depositional environment remained basinal as in the Hyblean
sector, where, however, carbonate deposits were associated with thick submarine lava flows.
During Neocomian age, while the central part of the studied area was still emerged (or
characterised by non-deposition), the northern part was gradually evolving from sea-mount to
basin.
At the end of the Neocomian (Fig. 4), also the central area sank and received terrigenous inputs
typical of the African area (Sidi Kralif and Fadhene Fms.), which did not reach the northern
sector (Lattimusa Fm.). To the South (Pelagian sector), the carbonate-terrigenous supply could
have led to a partial filling of the basin, as the basinal deposits are interbedded with thick
shallow marine horizons (Djebel Nehal, Serdj, Bou Hedma and Sidi Aich Fms.).
At the end of the Early Cretaceous (Aptian p.p.-Albian), the terrigenous inputs also reached the
northern part of the area (Hybla Fm.), but they are less thick than in the central and southern
parts (Fahdene and Hammeima Fms.).

Fig. 3. Areal distribution of the Toarcian-Dogger facies.

Fig. 4. Areal distribution of the Neocomian-Aptian facies.
In the Late Cretaceous the differentiation between the southern and northern zones of the
offshore decreased. In fact, in the whole Sicily Channel, basinal carbonate deposition (Scaglia
Fm.) set up.

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