Ammonoid faunas from the Cardium Formation (Turonian-Coniacian, Upper Cretaceous) and contiguous units, Alberta, Canada: I. Scaphitidae

Abstract

While the Cardium Formation (Turonian–Coniacian, Upper Cretaceous) is one of the major hydrocarbon sources, and consequently one of the most intensely studied siliciclastic formations in the Western Canada Sedimentary Basin, it remains one of the more controversial units in terms of understanding the depositional environments and processes it represents, and correlations between subsurface and outcrop. Proposed subsurface subdivisions based on sequence stratigraphic concepts, and relation of these allomembers to long-established members of the outcrop belt, have provoked further disagreements. The general lack of biostratigraphic data within the Cardium Formation makes it difficult to test different models and to resolve conflicting proposals. This paper provides stratigraphic and taxonomic information on all known scaphitid ammonoids from the Cardium Formation and correlation of these faunas with the Turonian and Coniacian zonal scheme established in the United States Western Interior; future publications will provide similar treatments of the collignoniceratid ammonites and inoceramid bivalves.