Anatomy and evolution of the normal-faulted Lower Pliocene fill of the northern Crotone Basin (southern Italy)

The complex development of the northern Crotone Basin, a forearc basin of the Calabrian Arc (Southern Italy), has been documented by sedimentological, stratigraphic and structural analyses.This Mediterranean-type fault bounded basin consists of small depocentres commonly characterized by a mix of facies that grades from continental to shallow marine.The lower Pliocene in¢ll of the Crotone Basin consists of o¡shore marls (Cavalieri Marl) that grade upwards into a shallow-marine to continentalsuccessionupto850mthick(ZingaFormation).Thesuccessionissubdividedintothree mainstratalunits:Zinga1,Zinga2,Zinga3boundedbymajorunconformities.TheZinga1stratalunit grades from the Cavalieri Marl to deltaic and shoreface deposits, the latter organized into several stacked progradational wedges that show spectacular thickness changes and progressive unconformities related to salt-cored NE-trending growth folds and listric normal faults.The Zinga 2 stratal unit records a progressive and moderate deepening of the area, marked by £uvial sedimentation at the base, followed by lagoonal deposits and by a stacking of mixed bioclastic and siliciclastic shoreface units, organized into metre-scale high-frequency cycles. Deposition was controlled by NE- trending synsedimentary normal faults that dissected the basin into a series of half-grabens. Hangingwall stratigraphic expansion was compensated by footwall condensed sedimentation. The extensional tectonic regime continued during sedimentation of the Zinga 3 stratal unit. Deposition con¢ned within structural lows during a generalized transgressive phase led to local enhancement of tidal £ows and development of sand-wave trains.The tectonic setting testi¢es the generalized structural domain of a forearc region.The angular unconformity at the top of the Zinga 3 stratal unit is regional, and marks the activation of a large- scale tectonic phase linked to strike- slip movements.