Predominantly fine-grained interval of grey, sandy to silty mudstones with thin intercalated sand, carbonate and coal beds, occasionally fossiliferous and/or sideritic. Intercalated carbonate beds are rarely encountered. In the Central Netherlands Basin, the formation appears to be slightly sandier, but also developed in a more calcareous lower part and a coaly upper part. In the Vlieland Basin, the formation also contains volcanclastic deposits.
Muddy coastal-plain, by settling from suspension during floodings. Thin sand sheets formed by crevasses, washovers, short transgressions and small-scale fluvial channels.
Often unconformably overlies the Lower Buntsandstein Formation or the Zechstein Group.
Often conformable underlies the Scruff Greensand Formation or Kimmeridge Clay Formation, Wadden Volcaniclastic Member; or unconformable underlies the Vlieland Sandstone Formation.
