Middle Graben Sandstone Member

SLCMS

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.

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.

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.

Up to 52 m.

UK: Humber Group; GER: ?; BEL: -.

early Oxfordian - middle Oxfordian.

Named after the Central Graben.

None.

Sander Houben (2017).

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..