Cenomanian Stage

the first stage from the bottom in the upper division of the Cretaceous system. The Cenomanian was first identified by the French geologist A. d’Orbigny in central France in 1847. At the type locality, near the city of Le Mans, it is represented by sands, clays, and marls containing abundant fossil shells of mollusks and foraminifers. The stage is widely represented in the USSR.