Cretaceous slopes are well known from many regions of the world, since they are amongthe most prone depositional systems to host hydrocarbons. As far as Italy, in spite of fullydescribed examples as the Majella and Gargano escarpments, detailed sedimentologicaland biostratigraphic studies from Sicily are not available, although the presence of slopecarbonates of Cretaceous age in northwestern Sicily, is mentioned in several papers dealingwith regional geology or geological mapping. The Cretaceous slope carbonates from thisarea, i.e. the San Vito Lo Capo Peninsula, belong to several thrust sheets of the Maghrebianchain. The stratigraphic setting in these tectonic units allows to reconstruct the aggradationof a thick carbonate platform during Late Triassic-earliest Jurassic, the drowning andconversion to a pelagic plateau during Pliensbachian-Toarcian and its evolution into a slope,since latest Jurassic times. The Cretaceous carbonates from this area are intenselyexploited as ornamental stones since the past century and are known with the commercialname of “Perlato di Sicilia”. The wire-cutted walls of a number of quarries either active orabandoned offer the opportunity to study in detail the facies architecture along the slope anddefine its sedimentary evolution throughout the Cretaceous.The preliminary results of the researches, that are carried out in the frame of a PhD studyon the stratigraphy and sedimentology of this depositional system, allow to document thepresence of slope to toe-of-slope sediments since at least the Aptian. The faciesassociations consist of gravitative skeletal sediments, mostly rudist rudstones to which areintercalated debrites and thick megabreccia beds formed by rudist-bearing extraclasts.Along the succession, the presence of repeated pillow lava intercalations highlights the roleof the tectonics in the slope evolution and the crustal involvement in the extensionalprocesses that have controlled the geometry of the slope. At present the slope sedimentscover an area of about 100 square kilometers, however, owing to the Maghrebiancontraction, the original extension of the slope is largely underestimated. Upsection, theoccurrence of pelagic, scaglia-type, sediments points to a significant reduction of the clasticsupply along the slope during lower Senonian times. However, debrites with Cretaceouscarbonate extra-clasts occur into the pelagic calcilutites until the Eocene.
|Numero di pagine||1|
|Stato di pubblicazione||Published - 2017|