Plio-Quaternary uplift rates in the outer zone of the central Apennines fold-and-thrust belt, Italy

Abstract

Geological, seismic and borehole data permitted the reconstruction of the Plio-Quaternary uplift/subsidence and erosion/sedimentation history for the outer sector of the central Apennines. During the latest contractional stages (Middle–Late Pliocene), the frontal sector of the belt experienced a net subsidence locally compensated by the growth of the fold-and-thrust system. This tectonic uplift was localized at the axial culmination of the anticlines and, particularly for the major structures, was responsible for exhumation and erosion of the Neogene succession and for near-flat planation surfaces development, on Meso-Cenozoic carbonate rocks, at the crest of the anticlines. Since the Early Middle Pleistocene, a regional doming involved the outer part of the belt (Peri-Adriatic Domain). This process interacted with Quaternary eustatic sea level fluctuations and caused the basinward migration of shallow marine deposits, forming an overall prograding system. Quaternary shoreline retreat, base level drop and climatic changes were mainly associated with valley deepening and fluvial terrace formation. The present study outlines that fold/thrust growth and regional doming driving processes, characterized by different amplitude, wavelength and uplift-rate amounts, are both responsible for the morphological setting of the central Apennines external zones.