Integrated stratigraphic, palaeontological, and geochemical analysis of the uppermost Hauterivian Faraoni Level in the Fiume Bosso section, Umbria-Marche Apennines, Italy

An integrated stratigraphic, palaeontological, and geochemical study has been carried out across the uppermost Hauterivian Faraoni Level of the Fiume Bosso section in the Umbria-Marche Apennines, Italy. This level represents a first, prominent sign of the global changes that led to the widespread deposition of mid-Cretaceous organic-rich facies. Marked changes in the organic geochemical record and microfloral and micro- and macrofaunal assemblages occur within the interval. They are characteristic for short-term deposition in strongly dysoxic bottom conditions. Such changes probably reflect climatic variation which, in turn, induced variations in the palaeoceanographic regime.