Old Red Group

OR

Formal (Van Adrichem Boogaert & Kouwe 1994; Cameron 1993a; Cameron 1993b).

Sandstones, siltstones and claystones with minor thin dolomite intercalations in the lower part. Red and red-brown colours prevail in the fine-grained intervals in most of the group. Felsic volcanic extrusives occur in the lower and middle part.

Continental setting. The sandstones and red and grey claystones are fluvial-channel and floodplain deposits. The grey, dolomitic claystones suggest deposition in limnic conditions. Active felsic volcanism occurred locally.

Rests unconformably on the Caledonian basement of the Elbow Spit High. In well A17-01 this basement consists of a grey and pinkish, very coarse-crystalline granite.

Overlain conformably by the Farne Group, which is characterized by the occurrence of limestone beds. Locally the group is overlain unconformably by younger formations (Rotliegend to Chalk groups) as a result of severe later erosion.

Up to 929 m in A17-01.

Only a few wells in the Netherlands have reached the Old Red Group, so little information is available on its areal distribution. Regional studies, however, indicate that this group has a wide distribution in the central and northern North Sea area (Cameron 1993a; Cameron 1993b).

UK: can be equated largely to the Upper Old Red Group; GER: ?; BEL: ?

Givetian - Tournaisian.

Named after the continental Devonian deposits, known in the UK as Old Red Sandstone.

None.

Tom van Hoof (2017).

Cameron, T.D.J. 1993a. Triassic, Permian and Pre-Permian of the Central and Northern North Sea. ln: Knox, R.W.O.B. & Cordey, W.G. (eds.), Lithostratigraphic nomenclature of the UK North Sea 4,-British Geological Survey, Nottingham, 163 p.

Cameron, T.D.J. 1993b. Carboniferous and Devonian of the Southern North Sea - ln: Knox. R.W.0'8. & Cordey, W.G. (eds.) Lithostratigraphic nomenclature of the UK North Sea 5, British Geological Survey, Nottingham, 94 p.

Van Adrichem Boogaert, H.A. & Kouwe, W.F.P. 1994. Stratigraphic nomenclature of The Netherlands; revision and update by RGD and NOGEPA, Section B, Devonian and Dinantian. Mededelingen Rijks Geologische Dienst, 50, 1-20.