Proposal for the Global Boundary Stratotype Section and Point (GSSP) for the Priabonian Stage (Eocene) at the Alano section (Italy)

Claudia Agnini1, Jan Backman2, Flavia Boscolo-Galazzo3, Daniel J. Condon4, Eliana Fornaciari1, Simone Galeotti5, 16, Luca Giusberti1, Paolo Grandesso1, Luca Lanci5, 16, Valeria Luciani6, Simonetta Monechi7, Giovanni Muttoni8, Heiko Pälike9, Maria Letizia Pampaloni10, Cesare A. Papazzoni11, Paul N. Pearson3, Johannes Pignatti12, Isabella Premoli Silva8, Isabella Raffi13, Domenico Rio1, Lorenzo Rook7, Diana Sahy4, David J.A. Spofforth14, Cristina Stefani1, and Bridget S. Wade15

1 Dipartimento di Geoscienze, Università di Padova, Padova, Italy 2 Department of Geological Sciences, Stockholm University, Stockholm, Sweden 3 School of Earth and Ocean Sciences, Cardiff University, Cardiff, United Kingdom 4 British Geological Survey, Keyworth, Nottingham, United Kingdom 5 Dipartimento di Scienze Pure e Applicate, Università di Urbino Carlo Bo, Urbino, Italy 6 Dipartimento di Fisica e Scienze della Terra, Università di Ferrara, Ferrara, Italy 7 Dipartimento di Scienze della Terra, Università di Firenze, Firenze, Italy 8 Dipartimento di Scienze della Terra “Ardito Desio”, Università di Milano, Milano, Italy 9 Marum, University of Bremen, Bremen, Germany 10 Istituto Superiore per la Protezione e la Ricerca Ambientale (ISPRA), Roma, Italy 11 Dipartimento di Scienze Chimiche e Geologiche, Università di Modena e Reggio Emilia, Modena, Italy 12 Dipartimento di Scienze della Terra, Università La Sapienza, Roma, Italy 13 Dipartimento di Ingegneria e Geologia, Università “G. dʼAnnunzio”, Chieti-Pescara, Italy 14 CGG MCNV (GeoSpec), Llandudno, United Kingdom 15 Department of Earth Sciences, University College of London, London, United Kingdom 16 Institute for Climate Change Solutions, Pesaro e Urbino, Italy


The base of the Priabonian Stage is one of two stage boundaries in the Paleogene that remains to be formalized. The Alano section (NE Italy) was elected by consensus as a suitable candidate for the base of the Priabonian during the Priabonian Working Group meeting held in Alano di Piave in June 2012. Further detailed research on the section is now followed by a formal proposal, which identifies the base of a prominent crystal tuff layer, the Tiziano bed, at meter 63.57 of the Alano section, as a suitable candidate for the Priabonian Stage. The choice of the Tiziano bed is appropriate from the historical point of view and several bio-magnetostratigraphic events are available to approximate this chronostratigraphic boundary and guarantee a high degree of correlatability over wide geographic areas. Events which approximate the base of the Priabonian Stage in the Alano section are the successive extinction of large acarininids and Morozovelloides (planktonic foraminifera), the Base of common and continuous Cribrocentrum erbae and the Top of Chiasmolithus grandis (nannofossils), as well as the Base of Subchron C17n.2n and the Base of Chron C17n (magnetostratigraphy). Cyclostratigraphic analysis of the Bartonian-Priabonian transition of the Alano section as well as radioisotopic data of the Tiziano tuff layer provide an absolute age (37.710 – 37.762 Ma, respectively) of this bed and, consequently, of the base of the Priabonian Stage.