Aye formation

The Aye Formation is a geologic formation in the Dinant Synclinorium, Belgium. It is part of the Condroz Group, at the base of the middle Famennian (Upper Devonian). It is characterized by the presence of a conodont fossil Palmatolepis rhomboidea.

It is composed mostly of greenish shales and siltstones with some lenses of sandstone. As it formed in an offshore position, in a subtidal wave-influenced environment, bioturbation features are significant. Cross-bedding structures also occur.

The stratotype is located in the area of Houyet and Aye in Belgium.

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