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The Maastrichtian Stage in NW Europe, and its brachiopod zonation

The uppermost Campanian-Maastrichtian of NW Europe is divided into twelve brachiopod zones. Each zone is defined by its lower boundary in a stratotype by the appearance or disappearance of a species. The upper boundary is then formed by the lower boundary of the next succeeding zone. The zones are given binomial names using the species names of the taxa defining the lower and upper boundary respectively. The zonation is mainly based on localities in Denmark and most of the zones can be traced to Sweden, Poland, DDR, NW-Germany and eastern England. The section at Kronsmoor, NW Germany is proposed as stratotype for the lower boundary of the Maastrichtian Stage. Stevns Klint is by definition stratotype for the upper boundary and thus for the Cretaceous-Tertiary boundary. It may be substituted by Nye Kl.iv, Denmark if it can be demonstrated that it contains a hiatus at the boundary. It is formally proposed to place the boundary at the base of the Fish Clay since all available evidence points towards a global isochronous nature of the boundary clay bed.