The Aptian GSSP candidate at Gorgo a Cerbara (Central Italy): an alternative interpretation of the bio-, litho- and chemostratigraphic markers

International audienceThe Maiolica-type Gorgo a Cerbara section (Central Italy) was proposed as GSSP candidate for defining the base of the Aptian Stage with the base of the reverse magnetochron CM0r as the primary datum. Comparison with well-documented, ammonite-bearing successions of southeast France shows that the bio-, litho- and chemostratigraphic events recorded in Italy, below, at, and above this magnetochron fall within the Martelites sarasini ammonite Zone. Since there is an agreement that the M. sarasini Zone is the last ammonite zone of the Barremian, the use of the base of magnetozone CM0r as a datum to define the Barremian/Aptian boundary is questioned