Chokerian

The Chokier alum shales, exposed in the Meuse valley between Namur and Liège (Belgium), were defined by d’Omalius d’Halloy in 1853 as the lower unproductive unit of the Carboniferous coal measures. From this original concept, both a lithostratigraphic and a chronostratigraphic unit were defined. The Formation of Chokier returned to d’Omalius d’Halloy’s original ‘houiller sans houille’ concept (Paproth et al., 1983). The intermediate ‘assise de Chokier’ (Stainier, 1901) reflected a hybrid litho-bio construction by using synchronous marine incursions or goniatite bands for subdivision and basin-... Mehr ...