Stortemelk Member

Code
SGGSS
Status
Formal (Van Adrichem Boogaert & Kouwe 1993).
Lithological description

Fine- to very fine-grained, argillaceous sandstones with intense bioturbation. Sands are often slightly calcareous, glauconitic, with thin streaks of lignite. Cores show some intercalations of up to coarse, glauconitic and sometimes argillaceous sandstone.

Depositional setting

Shoreface to offshore setting.

Definition of lower boundary

Mild unconformity with underlying Scruff Spiculite Member or undifferentiated Scruff Greensand Formation in the Terschelling Basin. The boundary is placed at the discontinuity (consistent basal peak) of the GR-log. In the case of a contact with the Scruff Spiculite Member, a downhole increase in the sponge spiculae content may be taken as an additional criterion. In the southern Central Graben the base may be unconformably underlain by the Skylge or Friese Front formations.

Definition of upper boundary

Conformably overlain by the Schill Grund Member (Lutine Formation). In the southern Dutch Central Graben an unconformable upper contact with the Vlieland Claystone Formation (Rijnland Group) may be possible locally.

Thickness indication
Up to 60 m.
Geographical distribution
Regional correlation
UK: Humber Group; GER: ?; BEL: -.
Age
late Berriasian.
Holostratotype
Depth (thickness) AH:
2079 - 2105 m (26 m)
Parastratotype
Depth (thickness) AH:
3021 - 3041 m (20 m)
Origin of name
Named after the Stortemelk, a channel of the outer tidal delta between the Wadden Islands of Vlieland and Terschelling.
Previous name(s)
None.
Reviewed by (date)
Sander Houben (2017).
References
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]). Stortemelk Member. In: Stratigraphic Nomenclature of the Netherlands, TNO – Geological Survey of the Netherlands. Accessed on [DATE] from http://www.dinoloket.nl/en/stratigraphic-nomenclature/stortemelk-member.