A novel chronostratigraphic framework for the Aptian-Albian paleoclimate events

The Aptian-Albian interval was marked by paleoclimatic changes encompassing volcanic events and monsoonal activity of which the precise timing were not well-defined. This study presents a ~ 20 Myr cyclostratigraphic framework and provides an extended astronomical timescale using magnetic susceptibility and anhysteretic remanent magnetization datasets from the Poggio le Guaine core (Umbria-Marche Basin, Italy). Using astronomical tuning, we infer new age constraints and timespans for: (1) the Aptian and Albian stages; (2) the magnetic polarity Chron M0r; (3) the Oceanic Anoxic Events; (4) bioevents and, (5) Cretaceous oceanic red beds. These results enhance our understanding of the interplay between paleoclimatic and biotic processes in the Early Cretaceous. This study establishes a new chronostratigraphic framework for the Aptian-Albian-the most comprehensive to date in terms of resolution, integration with other geochronological methods, and temporal coverage- offering new insights into bio-chemical-geomagnetic interactions and helping refine the Geological Time Scale.