3.2.1 Génicot Formation - GNC

Authors:

Description: Black shale, dark grey laminated siltstone and often thin beds of medium grey sandstone. Occasionally a conglomeratic sandstone bed occurs. Sometimes dark-coloured microbioturbations a few mm long (Chondrites sp.?) are present in the shale or siltstone. The base of the formation is located above the highest macrofossiliferous horizon of the Fosses Fm, the top of the formation above the highest siltstone/sandstone bed below the Criptia Group, in which a clear green-grey shale appears.

Stratotype: not defined yet; area between the city of Fosses and the village Sart-Eustache.

Area: Puagne-Sart-Eustache area, in the southern structural unit of the western part of the Condroz inlier.

Thickness: At least 150-200 m.

Age: Early to mid Llandovery, based on one graptolite level (Michot, 1927) from the Monograptus convolutus biozone, Aeronian (mid Llandovery).

Remark: The relation with the similar Faulx-les-Tombes Mbr with its “schistes mouchetés” (Fosses Fm) is not yet understood.

(B. DELCAMBRE and J. L. Pingot)