Formal (Van Adrichem Boogaert & Kouwe 1993).
Quartz-rich sandstones with minor marine and lagoonal claystone intercalations.
Deposited in a shallow-marine, littoral facies. Amalgamated beach bars were formed in a wave-dominated environment.
Definition of lower boundary
Stratigraphically rests on the Helm Member in the centre of the Broad Fourteens Basin. Unconformably covers older Mesozoic to Palaeozoic strata at the basin margins.
Definition of upper boundary
In general overlain by the Vlieland Claystone Formation.
UK: Valhall Formation; Ger: ~Minden-Braunschweig-Gruppe; BEL: -.
Origin of name
Named after the Helder oil field, Block Q01, Dutch off-shore sector.
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]). Helder Member. In: Stratigraphic Nomenclature of the Netherlands, TNO – Geological Survey of the Netherlands. Accessed on [DATE] from http://www.dinoloket.nl/en/stratigraphic-nomenclature/helder-member.