New data about the Piedimonte Formation (Monte Soro Unit): insights and constraints to the geodynamic evolution of the Sicilian Maghrebids.

A detailed study of the siliciclastic Piedimonte Fm (Sicilian Maghrebids), cropping out in north-eastern Sicily, between the Peloritani Mts. and the Etna Mt., has been carried out. The formation is tectonically covered by the Stilo-Capo d’Orlando Fm, which constitutes a siliciclastic succession unconformable above all the Internal Units of the Sicilian Maghrebids. The Piedimonte Fm resulted younger than the age previously considered in literature, being not older than late Oligocene (Late Chattian) at the base, and not older than early Miocene (Aquitanian) in the upper part. The Piedimonte Fm stratigraphically lies above the Variegated Clays Fm that, in turn, stratigraphically rests above the Monte Soro Fm. Therefore, the Piedimonte Fm constitutes the uppermost part of the Monte Soro Unit, which is re-defined in the present paper and which, from a paleogeographic point of view, is to ascribe to the innermost part (Mauretanian sub-domain) of the Maghrebian Flysch Domain. According to these results, the main phase of deformation of the most internal sector of the Sicilian Maghrebian Flysch Domain occurred not before than Aquitanian, in agreement with the Burdigalian age recognised in more external units.