Late Oligocene-early Miocene sedimentary evolution of the foreland basins in the Sicilian mobile belt: the example of the Peloritani area

In the northeastern corner of Sicily (Peloritani Mountains) thin bodies of hercynian crystalline basement, covered by Meso-Cenozoic veneers of sedimentary rocks, represent the highest and innermost Africa-vergent group of thrust units of the Sicilian Belt. The Peloritani tectonic edifice consists of a set of prevalently middle- to high-grade crystalline rocks (so-called Fondachelli Unit, Mandanici Unit and Aspromonte Unit) and thrusts over a thin tectonic wedge made of prevalently Mesozoic to Tertiary sedimentary covers overlying pre-Triassic low-grade metamorphic rocks (Longi-Taormina Unit). The tectonic bodies of the Peloritani thrust system are overlain by thick clastic sequences of late Oligoceneearly Miocene age (the so-called Stilo-Capo d'Orlando Formation). Previous work has pointed out the 'molassic' character of these clastic sequences, which postdate the main deformation phase of the Peloritani belt, started during Oligocene time. New structural data on the crystalline and sedimentary terrains, sedimentological analysis of the outcropping Oligo-Miocene foreland clastic deposits and their geometric relationships with the substrate, make it possible to recognize the syn-tectonic character and the timing of deformation of these basin-fill deposits, which are expressed by prograding clastic fans in the active margin of a foreland-foredeep system. This system has progressively been involved in the accretion of the Sicilian Belt and migration during the early Miocene towards the more external areas represented by the Sicilide sector. Seen in this light, three different lithological units have been distinguished to prdvide a framework for a review of the palaeotectonic significance of the overall Oligo-Miocene terrigenous covers of the Peloritani Thrust belt