Architectural styles of prograding wedges in a tectonically active setting, Crotone Basin, Southern Italy

摘要

The lower Pliocene shallow-marine to continental succession of the Crotone Basin, a small forearc basin on the Calabrian Arc, Southern Italy, is represented by a mixed terrigenous–carbonate succession, up to 850 m thick, known as the Zinga Molasse, deposited in an active tectonic setting dominated by extensional structures and halokinesis. The succession may be informally subdivided into three main sequences, Zinga 1, Zinga 2, Zinga 3, each bounded by major unconformities produced by the interaction of tectonics and eustasy. The Zinga 1 sequence records terrigenous input into the basin leading to the development of stacked progradational wedges of shoreface and deltaic deposits. Spectacular thickness changes and progressive unconformities result from the activation of NE-trending growth folds and listric faults, and indicate that deposition occurred during extensional deformation and salt tectonics. However, the regional extent of the surfaces, the lack of evidence for changes in the local tectonic regime between sequences and the presence of listric faulting within sequences all favour eustatic sea-level change as the main control on the sequence development, although local tectonics strongly controlled sedimentary architecture.