The BGS Lexicon of Named Rock Units — Result Details
Corallian Group
| Computer Code: | CR | Preferred Map Code: | Cr |
|---|---|---|---|
| Status Code: | Full | ||
| Age range: | Oxfordian Age (JO) — Oxfordian Age (JO) | ||
| Lithological Description: | Complex succession of interdigitating limestones, marls, sandstones, sands, siltstones, silts, spiculites, mudstones. | ||
| Definition of Lower Boundary: | First appearance of medium- or coarse-grained sand above the Oxford Clay Formation. In some areas, this also defines the top of that Formation but elsewhere, there is an intervening silty unit (West Walton Formation). | ||
| Definition of Upper Boundary: | In the Dorset reference area, at the base of the Inconstans Bed (Kimmeridge Clay Formation), which also marks the Oxfordian-Kimmeridgian stage boundary, but elsewhere at the base of the thick mudstone succession that spans that stage boundary (ie Ampthill Clay and equivalents, and Kimmeridge Clay). | ||
| Thickness: | To c.100m | ||
| Geographical Limits: | Dorset to Oxfordshire, and North Yorkshire. | ||
| Parent Unit: | Not Applicable (-) | ||
| Previous Name(s): | Corallian Formation [Obsolete Name and Code: Use CR]
(-160)
Corallian Beds (-815) Corallian Rocks (-816) |
||
| Alternative Name(s): | none recorded or not applicable | ||
| Stratotypes: | |||
| Reference Section | Coastal cliffs and foreshore between Weymouth and Ringstead Bay, Dorset. | ||
| Reference Section | Filey Brigg to the Hambleton Hills (inclusive), North Yorkshire (quarry and natural sections). | ||
| Type Area | Coast between Weymouth and Ringstead, Dorset, England | ||
| Reference Section | Howardian Hills, North Yorkshire (quarry and natural sections). | ||
| Reference(s): | |||
| Melville, R V and Freshney, E C. 1982. British Regional Geology: the Hampshire Basin and adjoining areas (4th Edition).(London ,HMSO for Institute of Geological Sciences). | |||
| Arkell, W J. 1936. The Corallian Beds of Dorset, Part 1: The Coast. Proceedings of the Dorset Natural History and Archaeological Society, Vol. 57, 59-93. | |||
| 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 | |||
| Johnson, A L A, 1983. Field meeting on the Corallian of Oxfordshire, 16th May 1982. Proceedings of the Geologists' Association, Vol 94, P. 177. | |||
| Fursich, F T. 1976. The use of macroinvertebrate associations in interpreting Corallian (Upper Jurassic) environments. Palaeogeography, Palaeoclimatology, Palaeoecology, Vol. 20, 235-256. | |||
| Sherlock, R L, 1960. London and Thames Valley. British Regional Geology. | |||
| Sun, S Q, 1989. A new interpretation of the Corallian (Upper Jurassic) Cycles of the Dorset Coast, Southern England. Geological Journal, Vol 24, p. 139. | |||
| Wright, J K. 1986. A new look at the stratigraphy, sedimentology and ammonite fauna of the Corallian Group (Oxfordian) of south Dorset. Proceedings of the Geologists' Association, Vol. 97, 1-21. | |||
| Arkell, W J. 1933. The Jurassic System in Great Britain (Oxford: Clarendon Press.) | |||
| Wright, J K. 1972. The stratigraphy of the Yorkshire Corallian. Proceedings of the Yorkshire Geological Society, Vol. 39, 225-266. | |||
| 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). | |||
| 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, 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). | |||
| Wright, J K, 1981. The Corallian rocks of north Dorset. Proceedings of the Geologists' Association, Vol.92, 17-32. | |||
| Hallam, A, 1975. Jurassic Environments, p.79,82-82,165. Cambridge. | |||
| Blake, J F, and Huddleston, W H. 1877. On the Corallian rocks of England. Quarterly Journal of the Geological Society of London, Vol. 33, 260-405. | |||
| 1:50K maps on which the lithostratigraphical unit is found, and map code used: | |||
| E341 E342 E237 E313 E252 E052 E282 E327 E055 E065 E064 E158 E187 E188 E204 E220 E253 E254 E265 E266 E268 E281 E343 | |||