The Early and Middle Eocene of Belgium.
(Ypresian & Lutetian)
 
 

 
 
In Belgium, the Eocene is represented by the Early Eocene Ypresian and Middle Eocene Lutetian. The unique clay quarry of Egem (NW Belgium) presents a very rich and diverse elasmobranch fauna of mid to late Ypresian age. This part of the Ypresian is absent in the Paris Basin (France) and very weakly presented in the Hampshire Basin (UK). The sedimentation took place in shallow water in a subtropical climate. More than five layers containing vertebrate remains are exposed. The faunal assemblages are very different.

 
Two important Middle Eocene formations with a similar lithology occur in central Belgium: the Brussel Sand Formation, Early Lutetian (calcareous nannofossil zone NP14) and the Lede Sand Formation, Middle Lutetian (NP15). Nowadays, the Brussel Sand Formation can only be observed on temporary outcrops. Two sandpits exposing the Lede Sand Formation, deposited in a warm shallow marine environment, were situated in Balegem and Oosterzele. At Oosterzele, the Lede Sand Formation overlies the glauconitic and non-fossiliferous Vlierzele Sand Member (late Ypresian). The basal gravel of the Lede Sands was formed after one or several transgressive periods, which probably eroded the underlying Brussel Sand Formation, the Aalter Formation (Ypresian/Lutetian boundary) and the continental Aalterbrugge Lignitic Horizon (latest Ypresian) (Steurbaut in Smith et al., 2004).
 

 

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VAN DEN EECKHAUT, G. & DE SCHUTTER, P., 2009. The Elasmobranch Fauna of the Lede Sand Formation at Oosterzele (Lutetian, Middle Eocene of Belgium). Palaeofocus, 1: 1-57, 2 figures, 2 tables, 22 plates.

SMITH, T., DE WILDE, B. & STEURBAUT, E., 2004. Primitive Equoid and Tapiroid mammals: keys for interpreting the Ypresian-Lutetian transition in Belgium. KBIN Bulletin, Aardwetenschappen, 74 supplement: 165-175.

WINKLER, T.C., 1873. Mémoire sur des dents de poissons du terrain Bruxellien. Extrait des archives du Musée Teyler, Vol. III, fasc. IV, Les Héritiers Loosjes, Haarlem.

WINKLER, T.C., 1874. Deuxième Mémoire sur des dents de poissons du terrain Bruxellien. Extrait des archives du Musée Teyler, vol. IV, fasc. I, Les Héritiers Loosjes, Haarlem.

HERMAN, J., STEURBAUT, E. & VANDENBERGHE, N., 2000. The boundary between the Middle Eocene Brussel Sand and the Lede Sand formations in the Zaventem-Nederokkerzeel area (Northeast of Brussels, Belgium). Geologica Belgica, 3/3-4: 231-255.

TAVERNE, L. & NOLF, D., 1979. Troisième note sur les poissons des Sables de Lede (Eocène belge): Les fossiles autres que les otolithes. Bulletin de la Société belge de Géologie/ Bulletin van de Belgische Vereniging voor Geologie, 87(3): 125-152. [1978]

CASIER, E., 1946. La faune ichthyologique de l'Yprésien de la Belgique. Mémoires du Musée royal d'Histoire naturelle de Belgique, 104: 1-267.

LERICHE, M., 1905. Les poissons éocènes de la Belgique. Mémoires du Musée royal d'Histoire naturelle de Belgique
, 11(3): 49-228.

© P. De Schutter - 2006-2011