A new perspective on the depositional environment of the Montefino Succession (Abruzzo Pliocene foredeep, central Italy)

The Montefino Succession (MoS) consists of a ~300 m thick Lower Pliocene siliciclastic succession, dominated by arenites with minor pelitic intercalations, mappable over tens of kilometers in northeastern Abruzzo. Since its first description, the MoS has been commonly interpreted as a turbiditic channel–lobe transition deposit and generally regarded as the uppermost part of the Cellino Formation. Ongoing field mapping carried out in the framework of the CARG Project (Sheet 350 – Penne) provides new evidence that is not fully consistent with this interpretation. Several field-based observations indicate littoral to paralic facies developed within a siliciclastic continental shelf. This suggests that a significant unconformity should separate the studied succession from the underlying Cellino Formation, whose facies are clearly referable to a foredeep basin. Accordingly, the MoS is here tentatively differentiated from the Cellino Formation and considered as a separate informal stratigraphic unit, possibly related to a deltaic or mixed (delta-fed/turbidite-like) depositional system.