The BGS Lexicon of Named Rock Units — Result Details

British Coastal Deposits Group

Computer Code: COAS Preferred Map Code: COA
Status Code: Full
Age range: Pliocene Epoch (NP) — Holocene Epoch (QH)
Lithological Description: Sands, gravels, silts and clays that contain clasts derived from rocks cropping out throughout Great Britain and the Isle of Man. Peat is also included where it forms a part of coastal sequences. The group includes glacio-isostatically uplifted (raised) deposits lying to the north of a hingeline crossing northern England between the Ribble and Tyne rivers, and isostatically uplifted interglacial shoreline deposits around the coast of southern Britain. Excludes deposits of the Crag Group of East Anglia.
Definition of Lower Boundary: Unconformable contact with units of the Britannia Catchments Group, the Caledonia Glacigenic Group, the Albion Glacigenic Group, the Dunwich and/or Crag groups, and bedrock.
Definition of Upper Boundary: Generally the ground surface, but units of this Group commonly interfinger with units of the Britannia Catchments Group. Raised beaches of Late Devensian age commonly interdigitate with units of the Caledonia Glacigenic Group.
Thickness: Up to 80 m.
Geographical Limits: Great Britain (England, Scotland, Wales and the Isle of Man).
Parent Unit: Great Britain Superficial Deposits Supergroup (GBG)
Previous Name(s): none recorded or not applicable
Alternative Name(s): none recorded or not applicable
Stratotypes:
Type Area  The coastline and estuaries of Great Britain and the Isle of Man. 
Reference(s):
McMillan, A A, Hamblin, R J O and Merritt, J W. 2004. An overview of the lithostratigraphical framework for Quaternary and Neogene deposits of Great Britain (onshore). British Geological Survey Research Report. RR/04/04. 
Bowen, D Q (Editor). 1999. A revised correlation of Quaternary deposits in the British Isles. Geological Society of London Special Report, No.23. 
Boulton, G S. 1992. Quaternary. 413-444 in Duff, P M D and Smith, A J (eds) Geology of England and Wales. [London: The Geological Society.] 
Boulton, G S, Peacock, J D and Sutherland, D G. 2002. Quaternary. 409-430 in Trewin, N H [editor], Geology of Scotland. [4th edition]. [London: The Geological Society.] 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
none recorded or not applicable