|Premise||Definition after NAM and RGD (1980) .|
|Type section||Location map||See figure (pdf)|
|Depth||1746 to 1953 m.|
|Length||207 m. along hole|
|Reference||NAM and RGD (1980)|
|Definition||A grey, homogeneous, somewhat marly, claystone, exhibiting a uniform, low acoustic-velocity and resistivity response on wire-line logs. The unit rests conformably upon the more calcareous Middle Werkendam Member. In a complete succession it is covered by the Brabant Formation. The basal member of the Brabant Formation displays an upward increase in limestone and sandstone content, reflected by a clear funnel shape on most wire-line logs (lower GR, higher sonic-velocity and resistivity readings). The base of the Brabant Formation has been placed at the base of the first clean limestone bed, marked by a sharp log peak.|
|References||See References Lower and Middle Jurassic|
Van Adrichem Boogaert, H.A. & Kouwe, W.F.P., 1993-1997. [Stratigraphic unit]. In: Stratigraphic Nomenclature of the Netherlands.
Retrieved [Datum] from [url].