Bacton Group

Bacton Group Stratigraphic range: Early Triassic epoch
Type	Group
Sub-units	Bunter Shale Formation, Bunter Sandstone Formation
Underlies	Haisborough Group
Overlies	Zechstein Group
Thickness	up to 600m[1]
Lithology
Primary	mudstones
Other	dolomitic sandstone
Location
Region	North Sea
Country	England
Type section
Named for	Bacton
Named by	Rhys, G.H.[2]

The Bacton Group is a Triassic lithostratigraphic group (a sequence of rock strata) beneath the southern part of the North Sea. The name is derived from Bacton on the Norfolk coast.These strata which are up to 600m thick are the offshore equivalent of the Roxby Formation and Sherwood Sandstone Group which occur in northeast England. The Group comprises a lower Bunter Shale Formation of red and brown to grey mudstones and an upper Bunter Sandstone Formation of dolomitic sandstones with mudstone interlayers.^[3]

References

1. Johnson, H, Warrington, G and Stoker, S J. 1994. Permian and Triassic of the Southern North Sea. In Knox, R W O'B and Cordey, W G (eds), Lithostratigraphic nomenclature of the UK North Sea. Nottingham: British Geological Survey.
2. Rhys, G H. 1974. A proposed standard lithostratigraphic nomenclature for the Southern North Sea and an outline structural nomenclature for the whole of the (UK) North Sea. Institute of Geological Sciences, Report No.74/8.
3. http://www.bgs.ac.uk/Lexicon/lexicon.cfm?pub=BACT (BGS on-line lexicon of rock units)