Upper Cretaceous cyclic sequences in Germany and marl–opal-rich Tortonian-Messinian strata in the Sorbas basin related to multiple sea drawdown have been correlated with Milankovitch orbital forcing.
The base is also close to the extinction level of the calcareous nanoplankton species Triquetrorhabdulus rugosus (the base of biozone CN10b) and the first appearance of nannoplankton Ceratolithus acutus.