Formal (Van Adrichem Boogaert & Kouwe 1994).
Sandstone-claystone couplet, grading laterally into massive sandstones in the basin-fringe area. The sandstone is light in colour and with large amounts of quartz. The claystone is red-brown.
Definition of lower boundary
Placed at the base of the sandstone, which forms a subtle unconformity, especially recognisable on the flanks of the Triassic highs. In the fringe area this sandstone is distinguished from the underlying Volpriehausen Formation by lower gamma-ray readings and a lower acoustic velocities.
Definition of upper boundary
Placed at the base of the first sandstone bed of the Hardegsen Formation or, near the swells, at the base of the unconformably overlying Solling Formation of the Upper Germanic Trias Group. In the basin-fringe area, this boundary is placed at the top of the uppermost of the claystone beds that occur in the upper part of the formation.
Considerable variation: 60 - 100 m in the Dutch Central Graben, 50 - 80 m in the Ems Low and 20 - 40 m in the West Netherlands Basin, Roer Valley Graben and Broad Fourteens Basin.
UK: Bunter Sandstone Formation; GER: Detfurth Formation; BEL: Detfurth Formation.
Origin of name
New formation name, derived from the German stratigraphic nomenclature.
It comprises the former Detfurth Sandstone and Detfurth Claystone members and their equivalents in the Middle Bunter Formation as defined by NAM and RGD (1980).
Geluk, M.C. 2005. Stratigraphy and tectonics of Permo-Triassic basins in the Netherlands and surrounding areas. PhD Thesis, Utrecht University, 171 p.
NAM & RGD 1980. Stratigraphic nomenclature of The Netherlands. Verhandelingen van het Koninklijk Nederlands Geologisch Mijnbouwkundig Genootschap 32, 77 p.
Van Adrichem Boogaert, H.A. & Kouwe, W.F.P. 1994. Stratigraphic nomenclature of The Netherlands; revision and update by RGD and NOGEPA, Section E, Triassic. Mededelingen Rijks Geologische Dienst, 50, 1-28.
TNO-GDN ([YEAR]). Detfurth Formation. In: Stratigraphic Nomenclature of the Netherlands, TNO – Geological Survey of the Netherlands. Accessed on [DATE] from http://www.dinoloket.nl/en/stratigraphic-nomenclature/detfurth-formation.