Integrated stratigraphy of the Lutetian-Priabonian pelagic section at Bottaccione (Gubbio, central Italy): A proposal for defining and positioning the Global Stratotype Section and Point (GSSP) for the base of the Bartonian Stage (Paleogene System, Eocene Series)

At present, the Global Stratotype Section and Point (GSSP) for the base of theBartonian remains the only GSSP of the Paleogene System to be defined by the Inter-national Subcommission on Paleogene Stratigraphy (ISPS) and the InternationalCommission on Stratigraphy (ICS). Here, we present the results of an integrated,high-resolution study of calcareous plankton and benthic foraminifera biostratigra-phy and a detailed magneto-, chemo-, and cyclostratigraphic analyses carried outthrough the upper Lutetian to the upper Priabonian pelagic sediments of the Bot-taccione Gorge section near Gubbio, central Italy, to check its stratigraphic com-pleteness and constrain in time the optimal interval for defining and positioning theGSSP for the base of the Bartonian Stage. The high-resolution and solid integratedstratigraphic framework established at Bottaccione confirmed the completeness ofthe section, which meets the ICS recommendations for a potential designation as aGSSP for the base of the Bartonian Stage. Thus, the Bottaccione section was com-pared with the parastratotype section of the Bartonian in its type area, Alum Bay,UK. On this basis, two reliable criteria for defining and positioning the BartonianGSSP at Bottaccione are provided: (1) the base of magnetic polarity chronozone C18ras the primary correlation criterion and (2) the base of the calcareous nannofossilDictyococcites bisectus, which defines the CNE14/CNE15 zonal boundary as a second-ary correlation criterion.