Tertiary silicoclastic turbidite systems of the Northern Apennines

Abstract

The turbidite beds of the Northern Apennines offer some of the most spectacular exposures of deep water synorogenic sediments in the world and have been often taken as representative of the typical foredeep basin fill. For the Miocene Marnoso-arenacea (MA) Formation in particular, the presence of several marker beds and of a well assessed biostratigraphy, coupled with an excellent stratal continuity, has allowed geologists to work out the shape of the basin through time, despite the tectonic slicing following the accretion of the sediments into the Apennine fold-and-thrust belt. The MA turbidites, however, represent just a time interval of a much longer story of foredeep sedimentation and migration that started in the late Oligocene and that continues at present (Ricci Lucchi, 1986b). For several reasons, the stratigraphy and geometry of the sedimentary beds of the Northern Apennine foredeep units have not always been documented in the same accurate way as the MA and the overall stratigraphie scheme is still to be refined. Within these limitations, this contribution aims at presenting a review of the stratigraphy, basin geometry and tectonic signature of the Tertiary foredeep deposits outcropping in the Northern Apennines. The Recent foredeep basin, which is located in the Po Plain and in the Adriatic Sea, is used as a modern analogue.