The BGS Lexicon of Named Rock Units — Result Details

Great Oolite Group

Computer Code: GOG Preferred Map Code: GtO
Status Code: Full
Age range: Bajocian Age (JB) — Callovian Age (JC)
Lithological Description: Variety of mudstone-dominated and ooidal, bioclastic and fine-grained limestone formations.
Definition of Lower Boundary: Change up from ooidal and/or pisoidal limestone (Salperton Limestone Formation/Lincolnshire Limestone Formation) or ironstone or ferruginous sandstone (Northampton Sand Formation), all of Inferior Oolite Group; overlain by silicate/calcareous mudstone (Fuller’s Earth Formation) or pale sandstone (Horsehay Sand Formation/Stamford Member of Rutland Formation) or sandy, fine-grained ooid limestone (Chipping Norton Limestone Formation). Generally a non-sequence or disconformity.
Definition of Upper Boundary: Base of succeeding Kellaways Formation; comprising mudstone, commonly shelly at base, resting generally sharply and conformably or non-sequentially on bioclastic limestone of the Cornbrash.
Thickness: About 20m through Lincolnshire and the Midlands (East Midlands Shelf), thickening south through the Cotswolds (60 to 90m) to 100 to 200m in Somerset and Dorset, and in the Weald subcrop (Green, 1992; Sumbler, 1996). Offshore English Channel up to 224m (Hamblin et al., 1992).
Geographical Limits: Dorset, Somerset, through the south-west Midlands, Oxon, Northants, part of Lincolnshire and northwards as far as the Market Weighton High (covering areas formerly including the outcrop of the now obsolete "Redbourne Group"): Also proved in borings in the Weald (Wyatt, 2011), the London area and Norfolk.
Parent Unit: Not Applicable (-)
Previous Name(s): Great Oolite [Obsolete Name and Code: Use CFDO, GOG] (-4534)
Great Oolite Formation [Obsolete: See CFDO] (GOF)
Great Oolite Series (-5115)
Redbourne Group (RDBN)
Great Oolite Limestone [Obsolete Name And Code: Use BWL, GOG or CFDO] (GOL)
Alternative Name(s): none recorded or not applicable
Stratotypes:
Type Area  Bath area. 
Reference(s):
Woodward, H B, 1894. The Jurassic Rocks of Britain, Vol.4. The Lower Oolitic Rocks of England (Yorkshire excepted). Memoir of the Geological Survey of the United Kingdom. 
Gaunt, G D, Fletcher, T P and Wood, C J. 1992. Geology of the country around Kingston upon Hull and Brigg. Memoir of the British Geological Survey, sheets 80 and 89 (England and Wales). 172pp. 
Torrens, H S, 1967. The Great Oolite Limestone of the Midlands. Transactions of the Leicestershire Literary and Philosophical Society, Vol.61, 65-90. 
Sumbler, M G, 1996. British regional geology; London and the Thames Valley. (4th edition). (London: HMSO for the British Geological Survey). 
Townsend, J. 1813. The character of Moses established for veracity as a historian, recording events from the creation to the deluge. (Bath: Gye; London: Longman.) 
Cox, L R, and Arkell, W J. 1948. A Survey of the Mollusca of the British Great Oolite Series. Monograph of the Palaeontographical Society. 
Cope, J C W (Editor) 1980b. A correlation of Jurassic rocks in the British Isles. Part Two: Middle and Upper Jurassic. Geological Society of London Special Report, No.15 
Arkell, W J. 1947. The Geology of Oxford. 267pp. [Oxford: Clarendon Press.] 
Waters, C N, Smith, K, Hopson, P M, Wilson, D, Bridge, D M, Carney, J N, Cooper, A H, Crofts, R G, Ellison, R A, Mathers, S J, Moorlock, B S P, Scrivener, R C, McMillan, A A, Ambrose, K, Barclay, W J, and Barron, A J M. 2007. Stratigraphical Chart of the United Kingdom: Southern Britain. British Geological Survey, 1 poster. 
Green, G W and Donovan, D T. 1969. The Great Oolite of the Bath area. Bulletin of the Geological Survey of Great Britain, Vol.30, 1-63. 
Judd, J W. 1875. The geology of Rutland and parts of Lincoln, Leicester, Northampton, Huntingdon and Cambridge. Memoir of the Geological Survey of Great Britain (Old Series sheet 64). 
Arkell, W J. 1933. The Jurassic System in Great Britain [Oxford: Clarendon Press.] 
Cope, J C W. 2006. Jurassic: the returning seas. The geology of England and Wales. Brenchley, P J, and Rawson, P F (editors). (London: Geological Society.) 
Green, G W. 1992. Bristol and Gloucester region (3rd). British Regional Geology. (London: HMSO for British Geological Survey.) 
Wyatt, R J. 2011. A gamma-ray correlation of boreholes and oil wells in the Bathonian Stage succession (Middle Jurassic) of the Wealden Shelf subcrop. British Geological Survey Open Report, OR/11/048. 
Barron, A J M, Lott, G K, and Riding, J B. 2012. Stratigraphical framework for the Middle Jurassic strata of Great Britain and the adjoining continental shelf. British Geological Survey Research Report RR/11/06. 
Warner, R. 1811. A new guide through Bath and its environs. (Bath.) 
Fox-Strangways, C. 1892. The Jurassic Rocks of Britain, Vol.1. Yorkshire. Memoir of the Geological Survey of the United Kingdom. 
Hamblin, R J O, Crosby, A, Balson, P S, Jones, S M, Chadwick, R A, Penn, I E, and Arthur, M J. 1992. The geology of the English Channel. British Geological Survey United Kingdom Offshore Regional Report. 
Arkell, W J and Donovan, D T. 1952. The Fuller's Earth of the Cotswolds and its relation to the Great Oolite. Quarterly Journal of the Geological Society of London, Vol.107, 227-253. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
E127 E144 E157 E159 E170 E171 E172 E185 E186 E187 E201 E202 E203 E217 E218 E219 E235 E236 E237 E251 E252 E253 E265 E268 E273 E281 E341 E342 E343 E081