Bio-magnetochronology for the upper Campanian - Maastrichtian from the Gubbio area, Italy: new results from the Contessa Highway and Bottaccione sections
Résumé
A new bio-chronostratigraphic framework is presented for the upper Campanian - Maastrichtian pelagic sediments of the Gubbio area (Bottaccione and Contessa Highway sections, Italy). New planktonic foraminiferal (FO of P. hantkeninoides), calcareous nannofossil (FO of M. prinsii, base acme of M. murus) and magnetostratigraphic data are provided and integrated to construct an age-depth curve based on the recent astronomical calibration of the late Campanian - Maastrichtian magnetic polarity time scale (Husson, D., Galbrun, B., Laskar, J., Hinnov, L. A., Thibault, N., Gardin, S., Locklair, R. E., 2011. Astronomical calibration of the Maastrichtian, Late Cretaceous. Earth and Planetary Science Letters 305, 328-340). All bio-horizons recorded in both sections fall on or are very close to the Line of Correlation (LOC), which testifies to the reliability of biochronologic studies in the Umbria-Marche basin. The proposed age model allows to estimate the sedimentation rates and the ages of calcareous nannofossil and planktonic foraminiferal bio-horizons in both sections. Also, it provides an excellent late Campanian - Maastrichtian reference for sections in the Umbria-Marche area and the entire Tethys. Due to the presence of a ∼425 kyr-long hiatus in Chron C31n of the Bottaccione section, the Contessa Highway section constitutes a more complete late Campanian - Maastrichtian reference for bio-magnetochronology in the Tethyan realm.