The BGS Lexicon of Named Rock Units — Result Details

Shipton Member

Computer Code: SHIP Preferred Map Code: WhL
Status Code: Full
Age range: Bathonian Age (JN) — Bathonian Age (JN)
Lithological Description: Pale grey to off-white or yellowish limestone, peloidal wackestone and packstone with subordinate ooidal and shell fragmental grainstone, and re-crystallised limestone with beds of argillaceous limestone, marl and mudstone or clay.
Definition of Lower Boundary: The base of the peloidal wackestone/packstone/grainstone, overlies marls and fine-grained ooidal grainstones of the Hampen Formation or Rutland Formation.
Definition of Upper Boundary: A generally sharp, erosive boundary, and commonly a bored and oyster-encrusted hardground,at the top of the Excavata Bed, which is a peloidal packstone at the top of the Shipton Member, and generally succeeded by a sandy mudstone or sandy limestone at the base of the Ardley Member.
Thickness: From 3 m to 10 m thick, increasing to the south-west, about 4 m thick in type section.
Geographical Limits: From the Stroud to Cirencester area of Gloucestershire, where passes westwards into the Athelstan Oolite Formation, north-eastward through Oxon and Buckinghamshire to the Brackley area, where it passes north-eastward into the Roade Member of the Blisworth Limestone Formation.WhL is the code for White Limestone Formation. On some sheets (219,235), because the Signet Member (Si) or Bladon Member (Bl) of the White Limestone Formation is separated, WhL is described as 'Shipton and Ardley Members, undivided' but the Shipton Member has not been, nor is likely to be separated on any 1:50k or 1:10k map.
Parent Unit: White Limestone Formation (WHL)
Previous Name(s): Excavata Beds (-4883)
Croughton Member (-1819)
Ardley Beds (-1179)
Alternative Name(s): none recorded or not applicable
Stratotypes:
Type Area  Cherwell Valley from Woodstock to Ardley north of Oxford. Palmer 1979 
Reference Section  Ardley Railway Cutting and Quarry. Arkell, W J, et al, 1933; Palmer, T J, 1973; Barker, M J, 1976; Sumbler, M G, 1984; Cox, B M, and Sumbler, M G. 2002. 
Type Section  Shipton-on-Cherwell Quarry. Arkell, W J, 1931; Barker, M J, 1976; Palmer, T J, 1979; Richardson, L, et al, 1946; Sumbler, M G, 1984; Cox, B M, and Sumbler, M G. 2002. See Sumbler, M G, 1984 for additional reference sections. 
Reference(s):
Arkell, W J, 1931. The Upper Great Oolite, Bradford Beds and Forest Marble of south Oxfordshire, and the succession of gastropod faunas in the Great Oolite. Quarterly Journal of the Geological Society of London, Vol.87,p. 563-629. 
Richardson, L, Arkell, W J and Dines, H G. 1946. Geology of the country around Witney. Memoir of the Geological Survey of Great Britain. Sheet 236 ( England and Wales). 
Arkell, W J, Richardson, L and Pringle, J, 1933. The Lower Oolites exposed in the Ardley-Fritwell railway cuttings, between Bicester and Banbury, Oxford. Proceedings of the Geologists' Association, Vol.44, 340-354. 
Palmer, T J, 1973. Field meeting in the Great Oolite of Oxfordshire. Proceedings of the Geologists' Association, Vol.84, p. 53-64. 
Barker, M J, 1976. A stratigraphical, palaeoecological and biometrical study of some English Bathonian gastropoda (especially Nerinacea). (University of Keele: Unpublished PhD thesis). 
Palmer, T J, 1979. The Hampen Marly and White Limestone formations: Florida-type carbonate lagoons in the Jurassic of central England. Palaeontology, Vol.22, 189-228. 
Sumbler, M G, 1984. The stratigraphy of the Bathonian White Limestone and Forest Marble formations of Oxfordshire. Proceedings of the Geologists' Association, Vol.95, 51-64. 
Palmer, T J, 1974. Some palaeoecological studies of the Middle and Upper Bathonian of Central England and Northern France. (University of Oxford: Unpublished D Phil. Thesis.) 
Cox, B M and Sumbler, M G. 2002. British Middle Jurassic Stratigraphy. Geological Conservation Review Series No.26. [Peterborough: Joint Nature Conservation Committee.] 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
E235 E217 E219 E236 E237 E218 E234