The BGS Lexicon of Named Rock Units — Result Details
Gunthorpe Member
Computer Code: | GUN | Preferred Map Code: | Gun |
---|---|---|---|
Status Code: | Full | ||
Age range: | Anisian Age (TA) — Ladinian Age (TD) | ||
Lithological Description: | Mudstone, red-brown, with subordinate dolomitic siltstone and fine-grained sandstone, greenish grey, common gypsum veins and nodules. | ||
Definition of Lower Boundary: | Conformable, gradational upward passage from dominantly finely laminated mudstone and sandstone of Radcliffe Member into blocky, deformed mudstone of the Gunthorpe Member. | ||
Definition of Upper Boundary: | Conformable, at abrupt base of lowest pale grey sandstone bed of the Cotgrave Sandstone Member, overlying red-brown blocky mudstone of the Gunthorpe Member. | ||
Thickness: | 70-90 m (71 m in Cropwell Bridge borehole, SK63NE/28). | ||
Geographical Limits: | Mapped at surface in south Nottinghamshire and Leicestershire; traceable using geophysical logs in subsurface throughout East Midlands and Northeast England. | ||
Parent Unit: | Sidmouth Mudstone Formation (SIM) | ||
Previous Name(s): | Carlton Formation and Harlequin Formation [Obsolete Name and Code: Use GUN]
(-3449)
Carlton Formation [Obsolete Name And Code: Part Of GUN] (CRLF) Harlequin Formation [Obsolete Name And Code: Part Of GUN] (HRQ) Gunthorpe Formation [Obsolete Name and Code: Use GUN] (-1578) |
||
Alternative Name(s): | none recorded or not applicable | ||
Stratotypes: | |||
Reference Section | Fulbeck 1 Borehole (SK85SE/25), Fulbeck, Lincolnshire; depth range 200.1 m-287.3 m. Curated core held at BGS Keyworth. | ||
Reference Section | Surface section in river cliff beside River Trent at Gunthorpe, Nottinghamshire; on the southeastern bank adjacent to the weir. 8 m section of the middle part of the member. | ||
Type Section | Cropwell Bridge Borehole (SK63NE/28), near Cropwell Bishop, Nottinghamshire; depth range 84.9 m-154.7 m. Curated core held at BGS Keyworth. | ||
Reference(s): | |||
Howard, A S, Warrington, G, Ambrose, K, and Rees, J G. 2008. A formational framework for the Mercia Mudstone Group (Triassic) of England and Wales. British Geological Survey Research Report, RR/08/04. | |||
Warrington, G, Audley-Charles, M G, Elliott, R E, Evans, W B, Ivimey-Cook, H C, Kent, P E, Robinson, P L, Shotton, F W and Taylor, F M. 1980. A correlation of the Triassic rocks in the British Isles. Special Report of the Geological Society of London, No.13. | |||
Charsley, T J, Rathbone, P A, and Lowe, D J. 1990. Nottingham: A geological background for planning and development. British Geological Survey Technical Report WA/90/1. | |||
Howard, A S, Warrington, G, Carney, J N, Ambrose, K, Young, S R and Pharaoh, T C. 2009. Geology of the country around Nottingham. Memoir of the British Geological Survey, Sheet 126 (England and Wales). | |||
Elliott, R E. 1961. The stratigraphy of the Keuper Series in southern Notinghamshire. Proceedings of the Yorkshire Geological Society, Vol. 33, 197-231. | |||
Charsley, T J. 1989. Geology of the Nottingham (south) district: 1:10,000 Sheet SK63NE and part of 1:50,000 Sheet 126 (Nottingham) and Sheet 142 (Melton Mowbray). British Geological Survey Technical Report, Onshore Geology Series, 89/4. | |||
1:50K maps on which the lithostratigraphical unit is found, and map code used: | |||
E126 E127 E142 E141 |