Westerbork Member

Formal (NAM & RGD 1980). Amended (Van Adrichem Boogaert & Kouwe 1993).
Lithological description

Interval of dark-grey, silty to pebbly, micaceous, glauconitic claystones to marls, often with a thin, glauconitic, argillaceous sandstone bed at its base. Dispersed iron oolites are encountered.

Depositional setting

Open-marine deposition.

Definition of lower boundary

Unconformably covers the Ruinen Member, or the Bentheim Sandstone Member of the Vlieland Sandstone Formation.

Definition of upper boundary

Conformably overlain by the Gildehaus Sandstone Member. The boundary is placed at the base of the first massive sandstone or conglomerate. Because of the prograding character of this sandstone unit, the contact will be somewhat diachronous. In salt-dome-margin areas the member can be covered unconformably by the Holland Formation.

Thickness indication
50 - 100 m.
Geographical distribution
Regional correlation
UK: Valhall Formation; GER: ~Minden-Braunschweig-Gruppe; BEL: -.
early - middle Hauterivian.
Depth (thickness) AH:
1091 - 1121 m (30 m)
Depth (thickness) AH:
1471.5 - 1544 m (72.5 m)
Origin of name
Named after the village of Westerbork in the province of Drenthe.
Previous name(s)
Reviewed by (date)
Sander Houben (2017).
NAM & RGD 1980. Stratigraphic nomenclature of The Netherlands. Verhandelingen van het Koninklijk Nederlands Geologisch Mijnbouwkundig Genootschap 32, 77 p.
Van Adrichem Boogaert, H.A. & Kouwe, W.F.P. 1993. Stratigraphic nomenclature of The Netherlands; revision and update by RGD and NOGEPA, Section G, Upper Jurassic and Lower Cretaceous. Mededelingen Rijks Geologische Dienst, 50, 1-80..
Cite as
TNO-GDN ([YEAR]). Westerbork Member. In: Stratigraphic Nomenclature of the Netherlands, TNO – Geological Survey of the Netherlands. Accessed on [DATE] from https://www.dinoloket.nl/en/stratigraphic-nomenclature/westerbork-member.