LUTETIAN STAGE

the second of four stages in the Eocene Series, representing all those rocks deposited on a global basis during the Lutetian Age (52 to 43.6 million years ago). Together with the overlying Bartonian Stage, the Lutetian Stage constitutes the Middle Eocene. The stage's name is derived from Lutetia, the ancient Latin name for Paris, France, whose surrounding area is usually considered the type district for the stage. Traditionally, the base of the Calcaire Grossier formation has been used to define the base of the Lutetian Stage; however, no global stratotype section and point (GSSP) has been defined. The Lutetian Stage often is taken to embrace three foraminiferal biozones (in ascending order): Hantkenina aragonensis, Globigerinatheka subconglobata, and Morozovella lehneri.