Formal (Herngreen & Wong 1989). Amended (Van Adrichem Boogaert & Kouwe 1993).
Yellow fine-medium, moderately sorted sandstone with calcareous cement. The sands are often characterised by one or two coal beds, showing a spiky character on the GR-log. The sandy bodies have a distinct coarsening upward trend. In a few areas a double sand body is present, both parts with a coarsening upward trend.
Prograding lake delta fill complexes.
Definition of lower boundary
Characterised by distinct (Gamma Ray, interval transit time & Resistivity) log breaks defining the contact with the underlying non-calcareous claystones of the Middle Graben Formation.
Definition of upper boundary
Characterised by distinct (Gamma Ray, Int. transit time & Resistivity) log breaks defining the contact with the overlying non-calcareous claystones of the Middle Graben Formation.
UK: Humber Group; GER: ?; BEL: -.
early Oxfordian - middle Oxfordian.
Origin of name
Named after the Central Graben.
Herngreen, G.F.W. and Wong, Th.E. 1989. Revision of the ’Late Jurassic’ stratigraphy of the Dutch Central North Sea Graben - Geol. en Mijnbouw, 68, p. 73-105.
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..
TNO-GDN ([YEAR]). Middle Graben Sandstone Member. In: Stratigraphic Nomenclature of the Netherlands, TNO – Geological Survey of the Netherlands. Accessed on [DATE] from http://www.dinoloket.nl/en/stratigraphic-nomenclature/middle-graben-sandstone-member.