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thrust fault that overrides the Punta Faraglione unit with a horizontal displacement of more than three
thousand metres (Incandela, 1996; Tavarnelli et al., 2003).
Post orogenic extension caused the introduction of normal faults. Favignana is a good example of such a
stage of extension after a major stage of thrusting. The geological cross section in figure 2.4b illustrates
both the compressional and extensional structures in Monte Santa Caterina. Uplift in the area occurred
during a third phase, caused by the still ongoing compression between the African and Eurasian plates.
Monte Santa Caterina is flanked on its eastern side by much younger deposits of Lower Pleistocene
bioclastic deposits (Abate et al., 1997; D’Angelo et al., 2005). This puts the border between the Trubi
Formation and the calcarenite at the Plio - Pleistocene boundary.
The other islands of the Aegadian archipelago, Marettimo in the east and Levanzo in the north, show the
same stratigraphical succession as Monte Santa Caterina on Favignana. However on the other two islands
no Lower Pleistocene terraces are present. Whether the latter were never deposited, or because they are
eroded or not uplifted is uncertain. Between Favignana and Marettimo a deep channel of more than 200
metres exists. Figure A.2 illustrates this in a nautical map of the Aegadian islands. The fact that the
shelf is interrupted by such a channel can have important consequences for the transport mechanism of
sediments. The conceptual geological model in chapter 5 will address with those issues.
Because the young age and the nowadays relatively calm structural setting, tectonic deformation and
other post-sedimentary processes are limited. Parts of the east Favignana calcarenites show fractures,
indicating some minor tectonic influence. Offsets are generally less than a couple of centimetres. The
elevation of the eastern part of Favignana, which can be up to fifty metres, suggests that some uplift
must have taken place. A sea level of that height is not realistic for the Lower Pleistocene Mediterranean.

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