It is part of the Condroz Group,[1] at the base of the middle Famennian (Upper Devonian).
It is characterized by the presence of a conodont fossil Palmatolepis rhomboidea.
As it formed in an offshore position, in a subtidal wave-influenced environment, bioturbation features are significant.
[2] The stratotype is located in the area of Houyet and Aye in Belgium.
You can help Wikipedia by expanding it.This article about a specific stratigraphic formation in France is a stub.