New stratigraphic constraints for the Quaternary source-to-sink history of the Amatrice Basin (central Apennines, Italy)

New stratigraphic constraints have been detailed for the Amatrice Basin, an intermountain morpho-structural depression of the central Apennines (Italy) hosting up to 60-m-thick Quaternary continental deposits. Through the results coming from a 1:5,000 scale field survey and from facies analyses, we documented the geometry, thickness, and extent of the post-orogenic continental deposits filling this basin. The Quaternary deposits form a complex architecture of purely aggradational and aggradational/degradational terraces with a dominant component of conglomerates and gravels, at the bottom, and subordinate sands, at the top. The Quaternary deposits overlie an up to 1-km-thick succession of flysch sediments that accumulated in the western Laga Basin during the Miocene syn-orogenic phases in central Apennines. The collected data are used to constrain the style and mechanisms of both syn-orogenic (i.e., subsidence and terrigenous sedimentation in foredeep environment) and post-orogenic (i.e., uplift, erosion, and continental sedimentation) phases documented for the central Apennines. In particular, the post-orogenic history of the Amatrice Basin, if compared with those of surrounding intermountain basins of the central Apennines, includes limited basin subsidence, reduced thickness of the post-orogenic covers and progressive deepening of the drainage network during the Quaternary. The results shed light on the source-to-sink history of the Amatrice Basin, which results from a long-lived interaction between regional-scale factors (climate changes, chain uplift, and extensional tectonic regime) that influenced the activity of the hydrodynamic pattern and the amount of intrabasinal sedimentation during the Quaternary.