A high resolution tephrochronological record of MIS 14-12 in the Southern Apennines (Acerno basin, Italy).

Lithological, mineralogical, and glass chemical analyses on juvenile fragments extracted from 20 tephra layers embedded within the lacustrine sediments of the Acerno basin (Southern Apennines, Italy) were carried out together with four sanidine 40Ar/39Ar age determinations. The measured ages span the interval between 561 and 493 ka. Middle Pleistocene eruptive activity at Roman Province volcanoes was identified as the main possible source of the investigated tephra layers. Some of them were correlated with precise terrestrial counterparts corresponding to large explosive events of the Sabatini (e.g. Tufo Giallo della Via Tiberina) and Alban Hills volcanic districts (e.g. Tufo Pisolitico di Trigoria). The integration of tephrochronology and pollen analyses allowed the Acerno lacustrine sedimentation to be constrained between MIS 14 and 12, which overlaps with several well-studied, lacustrine successions of the Southern Apennines. The correlation with other tephrostratigraphic records from intramontane basins in central-southern Apennines testifies to the wide dispersal of at least three tephra layers that serve as marker layers, thus improving the resolution of the Middle Pleistocene Italian tephrostratotype.