The dismembering of the Adria platforms following the Late Cretaceous-Eocene abortive rift: a review of the tectono-stratigraphic record in the southern Apennines

We present a review of the Maastrichtian-Miocene tectono-stratigraphic evolution of the southern Apennines. Starting from the Late Cretaceous, a large part of the Africa-Adria domain, from Lybia to Italy, was affected by an abortive rift event. In the Maastrichtian-Eocene interval, it caused the dismembering of the Apennine and Apulian platforms. The rifting, accompanied by anorogenic magmatism and a severe extension, triggered the drowning of some shallow-water realms with the sedimentation of slope-to-basin deposits. Synchronously, the surrounding pre-existing slope-basin areas were the location of a widespread calciclastic supply. We described the stratigraphic records of this event in several key places of the southern Apennines and compared them to the corresponding rocks in Sicily, central Apennines, and Dinarids. The reconstructed Maastrichtian-Eocene palaeogeographic map shows remnants of the Apennine and Apulian platforms again in shallow-water conditions or forming emerged areas, surrounded by slope-to-deep basin sectors. We propose a depositional model where the exposed Mesozoic carbonates were eroded, producing a calciclastic supply deposited in the drowned carbonate domains and the pre-existing surrounding basins. Along the slope, the calciclastic sediments deposited as aprons at the toe of fault scarps and as isolated debris and channel-fan deposits up to the deep basin. Scaglia-type successions are also present, characterized by a mix of calcareous and clayey sediments. Finally, calciclastic turbidites and isolated calciruditic bodies are intercalated with widespread clayey deposits in the deep basin.