Famennian Stage

the upper stage of the upper series of the Devonian system. The Famennian stage was identified by the Belgian geologist A. Dumont in 1855. In its type locality, the stage is represented by sandstones, shales, and limestones containing brachiopods and other organic remains; in the Rhine region of West Germany there are bathypelagic shales and limestones containing cephalopods.

The Famennian stage is divided into two or, occasionally, three substages and several biozones (as many as five). Deposits of the Famennian stage are widespread in the USSR. They are represented by limestones and sand-shale strata, as well as by variegated continental formations and lagoon formations, that is, evaporites formed by the retreat of the sea and by drainage and salination in regions of sediment accumulation.