Crag/Lias Group separation map

Area where aquifer and shale/clay are present	North-east Norfolk
Thickness of intervening strata	350 to 550 m
Lithology of intervening strata	Permeable Great Oolite Group and Inferior Oolite Group (principal aquifer) Low permeability Kellaways Formation and Oxford Clay Formation (clay) Low permeability Kimmeridge Clay Formation and Ampthill Clay formations (clay) Permeable Lower Greensand Group (principal aquifer) Mixed permeability Upper Greensand Formation and Gault Formation (clay) Permeable Chalk Group (principal aquifer) Permeable Thanet Foormation Permeable Lambeth Group Low permeability Thames Group
Other major aquifers in the area	Permian sandstone (below) Triassic sandstones (below) Magnesian limestone (below) Carboniferous limestone (below)
Other shales or clays in the area	None
Aquifer map	Crag principal aquifer
Shale/clay map	Lias Group shale/clay unit

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