A marine fossil assemblage from the Foremost Formation (Cretaceous, Campanian), southern Alberta, and an evaluation of North American Cretaceous elasmobranch biostratigraphy
A transgressive-regressive cycle located within the transitional marine to terrestrial Foremost Formation marks the last major landward incursion of the Pakowki Sea during its overall regression. A hardground surface occurs at the point of maximum flooding, and is overlain by a mixed parautochthonous-allochthonous fossil assemblage. Physical characteristics of the fossil assemblage, and its position with respect to the shoreline, suggest it was formed by a single high energy depositional event. The elasmobranch fauna collected from the study site includes the following genera: Hybodus, Centrophoroides, Squatirhina, Odontaspis, Carcharias, Synodontaspis, Archaeolamna, Squalicorax, Paraorthacodus, Synechodus (new species), Protoplatyrhina, Myledaphus and Ischyrhiza This assemblage is characteristic of Campanian-Maastrichtian elasmobranch faunas from North America. Elasmobranch teeth possess the necessary attributes of index fossils. However, past errors associated with the collection and identification of elasmobranch teeth have limited their use, and must be corrected before their full potential can be realized.
Bibliography: p. 111-134.
Beavan, N. R. (1995). A marine fossil assemblage from the Foremost Formation (Cretaceous, Campanian), southern Alberta, and an evaluation of North American Cretaceous elasmobranch biostratigraphy (Master's thesis, University of Calgary, Calgary, Canada). Retrieved from https://prism.ucalgary.ca. doi:10.11575/PRISM/21237