Planktic and benthic foraminiferal distribution patterns as a response to changes in surface fertility and ocean circulation: a case study from the Late Albian ‘Amadeus Segment’ (Central Italy)

Abstract. A combined geochemical and micropalaeontological study of the late Albian ‘Amadeus Segment’ of the Aptian–Albian organic-rich Scisti a Fucoidi Formation in central Italy shows that planktic foraminiferal assemblages record changes in abundance and composition which are markedly related to CaCO₃ and Total Organic Carbon content of the sediments. The distribution pattern of different genera seems to record changes in nutrient supply and surface water temperature. Changes in palaeoceanographic regime are also reflected in abundance, composition and trophic structure of benthic foraminiferal assemblages as a response to variations of oxygen content and organic flux to the sea floor.