Sedimentological and taphonomic characterization of low energy rudist-dominated Senonian carbonate shelves (Southern Apennines, Italy).

Studies carried out on Upper Cretaceous rudist-bearing carbonate sequences in the central-southern Apennines highlighted two main depositional settings characterized by different hydrodynamic behaviour: high-energy vs. low-energy settings. The purpose of the present paper is to provide an overview of the lithofacies and of the depositional geometries of Upper Cretaceous rudist-bearing limestones pertaining to the centralsouthern Apenninic carbonate successions, in which low-energy to intermittently perturbed conditions can be recognized. The depositional sites were characterized by a large-scale facies polarity. Under closer examination, a patchy distribution of the latter appears, often related to channelized systems or current pathways through rudist settlement areas. The resulting depositional successions are characterized by peloidal silty-muddy sediments with periodical intercalations of fundamentally porous, coarse bioclastic deposits, in a generally tabular stacking. These geometries appear of great interest in relation to the prediction of geometries and porosities of the coarse-grained sedimentary bodies that intercalate and/or laterally pass to fine-grained deposits.