Formal (Van Adrichem Boogaert & Kouwe 1994).
Dark-grey, partly black, calcareous, laminated claystone.
Represents an Oceanic Anoxic Event (OAE2), a world-wide sea-level highstand, coupled with a rise of the oxygen-minimum zone and large-scale organic carbon deposition and burial.
Definition of lower boundary
Can be distinguished from the underlying Texel Marlstone Member by its high clay content which causes a distinct kick on gamma-ray, acoustic and resistivity logs.
Definition of upper boundary
Can be distinguished from the overlying Ommelanden Formation by its high clay content which causes a distinct kick on gamma-ray, acoustic and resistivity logs.
Generally does not exceed 10 m.
UK: Plenus Marls Member; GER: ?; BEL: ?
Cenomanian - Turonian boundary.
Origin of name
Named after comparable beds in the United Kingdom, kown as the 'Plenus Marl', characterized by the belemnite Actinocamax plenus.
Before 1994 (Van Adrichem Boogaert & Kouwe 1994) these deposits were included in the Texel Marlstone Member.
Reviewed by (date)
Mark Geluk, Geert-Jan Vis (2017).
Van Adrichem Boogaert, H.A. & Kouwe, W.F.P. 1994. Stratigraphic nomenclature of The Netherlands; revision and update by RGD and NOGEPA, Section H, Upper Cretaceous. Mededelingen Rijks Geologische Dienst, 50, 1-20.
TNO-GDN ([YEAR]). Plenus Marl Member. In: Stratigraphic Nomenclature of the Netherlands, TNO – Geological Survey of the Netherlands. Accessed on [DATE] from https://www.dinoloket.nl/en/stratigraphic-nomenclature/plenus-marl-member.