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.