The BGS Lexicon of Named Rock Units — Result Details

Stanford Formation

Computer Code: STFD Preferred Map Code: St
Status Code: Full
Age range: Oxfordian Age (JO) — Oxfordian Age (JO)
Lithological Description: Shell detrital limestones, ooidal limestone, coralline limestone, fossiliferous marls, and interbedded limestone, marl and mudstone.
Definition of Lower Boundary: Top of highest sandy lithology of underlying Kingston Formation (or silty mudstone of West Walton Formation, where the former is absent) above which succession is dominated by (non-sandy) limestone and/or marl; generally sharp and non-sequential boundary, commonly marked by pebble bed.
Definition of Upper Boundary: Top of limestone and/or marl-dominated succession succeeded by grey mudstones and silty mudstone of Ampthill Clay Formation; generally a sharp, non-sequential boundary. Locally unconformably succeeded by Lower Cretaceous (Lower Greensand Group).
Thickness: 0 to 26 m (Oxford area); up to c. 15 m (Calne-Swindon area).
Geographical Limits: Westbury, Wilts (where overstepped by Lower Cretaceous) to Waddesdon, near Aylessbury, Bucks (where wedges out into Ancholme Group; Horton et al., 1995).
Parent Unit: Corallian Group (CR)
Previous Name(s): Calne Freestone And Coral Rag (-1843)
Wheatley Limestone And Faringdon Members (-1844)
Cumnor Formation [Obsolete Name And Code: Use STFD] (CUMR)
Osmington Oolite Series (-1450)
Wheatley Limestone, Oakley And Littlemore Members (-1203)
Upper Corallian Limestones (-546)
Alternative Name(s): none recorded or not applicable
Stratotypes:
Reference Section  Harwell No. 3 (HW3) Borehole (SU48NE/92), 192.58 m to 196.80 m depth. (Gallois and Worssam, 1983). 
Reference Section  British Geological Survey Uffington (Manor Farm) Borehole (SU38NW/1), 51.76 m to 56.08 m depth. (Poole and Kelk,1971). 
Type Section  Shellingford Crossroads Quarry, near Stanford in the Vale, Oxon (Arkell, 1947, p. 87; McKerrow and Kennedy, 1973; Coe, 1995; Goldring et al., 1998; Cox, B M and Wright, J K. 2001). 
Type Area  The 'Corallian Ridge' between the rivers Thames and Ock (Vale of White Horse); approximately Swindon to Oxford. 
Reference Section  Cross Roads Quarry, New Headington, Oxford (Horton et al., 1987; Cox, B M and Wright, J K. 2001). 
Reference Section  British Geological Survey Cumnor (Henwood Farm) Borehole (SP40SE/11), 11.94 m to 20.35 m depth. (Horton, 1978; Horton et al., 1995) 
Reference Section  British Geological Survey Garsington Borehole (SP50SE/49), 10.31 m to 21.60 m depth. (Horton et al., 1995). 
Reference(s):
Arkell, W J. 1951. The geology of the Corallian ridge between Wootton Bassett and Lyneham, Wiltshire. Wiltshire Archaeological and Natural History Magazine, Vol.54, 1-18. 
Callomon, J H. 1960. New sections in the Corallian Beds around Oxford and the subzones of the Plicitalis Zone. Proceedings of the Geologists' Association, Vol. 71, p. 177-208. 
Coe, A L. 1995. A comparison of the Oxfordian successions of Dorset, Oxfordshire and Yorkshire. 151-172 in Taylor, P D (Ed.) Field Geology of the British Jurassic. [Bath: The Geological Society.] 
Cox, B M and Wright, J K, 2001. British Upper Jurassic stratigraphy (Oxfordian to Kimmeridgian). Geological Conservation Review Series, No. 21. (Peterborough: Joint Nature Conservation Committee.) 
Gallois, R W and Worssam, B C. 1983. Stratigraphy of the Harwell boreholes. Institute of Geological Sciences Report FLPU 83-14. 
Horton, A, Sumbler, M G, Cox, B M and Ambrose, K, 1995. Geology of the country around Thame. Memoir of the British Geological Survey, Sheet 237 (England and Wales). 
Poole, E G and Kelk, B. 1971. Calcium montmorillonite (fuller's earth in the Lower Greensand of the Baulking area, Berkshire. Institute of Geological Sciences Report 71/4. 
Arkell, W J. 1947. The Geology of Oxford. 267pp. [Oxford: Clarendon Press.] 
Arkell, W J. 1941a. Map of the Corallian Beds around Highworth, Wiltshire. Proceedings of the Geologists' Association, Vol.52, 79-109. 
Arkell, W J. 1941b. Map of the Corallian Beds around Purton, Wiltshire. Wiltshire Archaeological and Natural History Magazine, Vol.49, 274-282. 
Wright, J K, 1980. Oxfordian Correlation Chart. "In" Cope, C J W, (Editor). A correlation of Jurassic rocks in the British Isles, Part two: Middle and Upper Jurassic. Geological Society of London Special Report No.15. (p.61-76 in Correlation Chart). 
Arkell, W J, 1927. The Corallian rocks of Oxford, Berkshire and north Wiltshire. Philosophical Transactions of the Royal Society of London, Vol.B216, 67-181. 
Wright, J K and Cope, J C W. In press. Oxfordian - Kimmeridgian Correlation Chart. In: A correlation of Jurassic rocks in the British Isles: Middle and Upper Jurassic. Cope, J C W (editor). Special Report of the Geological Society of London. 
Golding, R, Layer, M G, Magyari, A, Palotas, K and Dexter, J. 1998. Facies variation in the Corallian Group (U. Jurassic) of the Faringdon-Shellingford area (Oxfordshire) and the rockground base to the Faringdon Sponge Gravels (L. Cretaceous). Proceedings of the Geologists' associatio;n, Vol. 109, p. 115-125. 
Horton, A. 1978. The Cumnor (Henwood Farm) Borehole. p.4 in Institute of Geological Sciences Boreholes. 1976. Institute of Geological Sciences Report 77/10. 
Arkell, W J. 1939. Map of the Corallian Beds between Marcham and Faringdon, Berkshire. Proceedings of the Geologists' Association, Vol.50, 487-509. 
McKerrow, W S and Kennedy, W J. 1973. The Oxford district. Geologists' Association Guide No.3. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
E236 E237 E252 E253 E265 E266 E281