Correlation of Albian European and Tethyan ammonite zonations and the boundaries of the Albian Stage and substages: some comments

Although the so-called ‘standard’ ammonite zonation of the Albian contains index species which occur in the Tethyan province, the scheme largely reflects the faunal succession in the European faunal province with its endemic sonneratiinid and hoplitinid faunal elements. Workers in the Tethyan province, stretching from South America in the west to Australia in the east, including southern Africa, Madagascar and India, face problems in the correlation of their successions with this so-called ‘standard’ scheme. There are other problems in that the succession of hoplitinid ammonites used in the biostratigraphy of European Albian sediments allows a far more detailed zonation to be made than in the case of some of the longer time-ranging Tethyan forms. This paper comments on proposals made recently for the delimiting of the base of the Albian Stage, and the Middle and Upper Substages, based on ammonite faunas. New information which affects the Albian ammonite zonation in the European faunal province and its correlation with the Tethyan province is discussed. The current hierarchical framework of zones and subzones used in the European faunal province may prove to be unsatisfactory in interprovincial correlation and particularly if the lower boundary of the Albian Stage was placed within the current Leymeriella tardefurcata ammonite Zone, instead of at its base.