Ubachsberg Member

Formal (Van Adrichem Boogaert & Kouwe 1995).
Lithological description

Massive sandstone bed, or set of beds, separated by light to dark-grey mudstone intervals, at or near the top of the Epen Formation. The sands are grey, very fine- to medium-grained, fairly well-sorted, well-cemented, thinly-bedded (smaller than 2 m), stacked into bed sets of 10 to 25 m thick. Disperse carbonaceous matter is common, but coal seams are absent. A number of intercalated clay layers with marine fossils is observed locally. In some cases, these can be correlated with specific marine bands.

Depositional setting

Turbiditic delta-front deposits, mouth bars, distributary-channel fills and associated overbank deposits. Intercalated fines reflect a combination of turbiditic and pelagic deposition. Marine incursions occurered into the predominantly lacustrine basin.

Definition of lower boundary

Placed at the base of the lowermost sandstone interval which is more than 10 m thick.

Definition of upper boundary

Placed at the top of the (uppermost) thick sandstone interval or below the lowermost coal seam of the Baarlo Formation.

Thickness indication
Up to 215 m.
Geographical distribution
Regional correlation
UK: Millstone Grit Formation; GER: ?; BEL: ?.
Depth (thickness) AH:
1609 - 1717 m (108 m)
Depth (thickness) AH:
2622 - 2656 m (34 m)
Origin of name
Named after the village of Ubachsberg in the Dutch province of Limburg.
Previous name(s)
Reviewed by (date)
Tom van Hoof (2017).
Van Adrichem Boogaert, H.A. & Kouwe, W.F.P. 1995. Stratigraphic nomenclature of The Netherlands, revision and update by RGD and NOGEPA, Section C, Silesian. Mededelingen Rijks Geologische Dienst, 50, 1-40.
Cite as
TNO-GDN ([YEAR]). Ubachsberg Member. In: Stratigraphic Nomenclature of the Netherlands, TNO – Geological Survey of the Netherlands. Accessed on [DATE] from https://www.dinoloket.nl/en/stratigraphic-nomenclature/ubachsberg-member.