The Global Boundary Stratotype Section and Point (GSSP) of the Campanian Stage at Bottaccione (Gubbio, Italy) and its Auxiliary Sections: Seaford Head (UK), Bocieniec (Poland), Postalm (Austria), Smoky Hill, Kansas (USA), Tepayac (Mexico)

Following the unanimous vote of the Executive Com-mittee of International Union of Geological Sciences in October 2022, the Global boundary Stratotype Section and Point for the base of the Campanian Stage is con-firmed as the magnetic polarity reversal from Chron 34n (top of the Long Cretaceous Normal Polarity-Chron) to Chron C33r at the 221.53 m level in the Bottaccione Gorge section at Gubbio, Umbria-Marche Basin, Italy. This event has been widely identified in oceanic settings and in wide-spread onshore outcrops. Sedimentation across the San-tonian-Campanian boundary interval in the proposed GSSP appears to be continuous, supported by evidence from the carbon isotope record and complete micro- and nannofossil biostratigraphy. The succession comprises deep-water cherty limestones (mudstones and foraminiferal wackestones) which provide a detailed record of calcareous nannofossils and planktonic foraminifera and yields an excellent palaeomagnetic record. The high-resolution carbon isotope record, derived from bulk sediment, provides an important additional means of correlation to other regions.