Upper North Sea Group Middle North Sea Group Lower North Sea Group Chalk Group Rijnland Group Niedersachsen Group Scruff Group Schieland Group Altena Group Upper Germanic Trias Group Lower Germanic Trias Group Zechstein Group Upper Rotliegend Group Lower Rotliegend Group Limburg Group Carboniferous Limestone Group Farne Group Banjaard group Old Red Group Silurian Igneous rock Not interpreted