Post-rift extensional tectonics at the edge of a carbonate platform: insights from the Middle Jurassic-Early Cretaceous Monte Giano stratigraphic record (central Apennines, Italy)

A new interpretation of the Middle Jurassic-Early Cretaceous paleogeographic evolution NW sector Latium-Abruzzi carbonate platform facing Umbria-Marche Basin is proposed, based on Monte Giano area (central Apennines, Italy). During Late Triassic-early Bajocian time, was characterized by shallow water sedimentation. Inner and marginal deposits are overlain pelagic (Posidonia level), early p.p. in age. This unconformity testifying sudden drowning area, while sedimentation persisted remaining sectors platform. The Posidonia level paraconformably distal slope Velino Gorge limestones Formation, Kimmeridgian p.p.-Tithonian Therefore, a 12Ma gap recorded as platforms. An extensional tectonic phase, possibly related to Piemont-Ligurian Ocean opening coupled with rheologic differences at basin/platform boundary, drastically changed regional paleogeography causing breakup creation large flat-topped estimate offset fault around 300-350m. fm. pass laterally vertically Upper Tithonian platform-margin reef complex Ellipsactinia fm.; these units constitute shallowing coarsening upward sequence levelled paleobathymetric gradient created extension. progradation continued during Early time. These results have strong implications major domains central Apennines.