3.2.11. Lustin Formation - LUS

Authors: Coen-Aubert & Coen, 1975; Coen-Aubert, 1999b.

 

Description: The lower part consists chiefly of a massif biostrome with branched stromatoporoids and corals with a few beds of crinoidal and dolomitic limestone below its base and overlaid by argillaceous limestone with branched colonial corals; the middle part consists of biostromal limestone mainly with tabular stromatoporoids; the upper part consists of well bedded micritic limestone with massif stromatoporoids in the uppermost part.

 

Stratotype: Frênes Cliffs at Lustin; the formation is also well exposed in the nearby Tailfer Quarry.

 

Area: northern part of the Dinant Synclinorium, southern part of the Namur Synclinorium, south-eastern border of the Dinant Synclinorium between Remouchamps and Aywaille and Vesdre Nappe.

 

Thickness:a little more than 100 m in the type area.

 

Age: Middle Frasnian; the lower part of the Lustin Formation most likely belongs to the punctata conodont Zone and the upper part to the Lower rhenana Zone (Coen- Aubert & Coen, 1975; Gouwy & Bultynck, 2000).