The BGS Lexicon of Named Rock Units — Result Details
Scunthorpe Mudstone Formation
| Computer Code: | SMD | Preferred Map Code: | SMd |
|---|---|---|---|
| Status Code: | Full | ||
| Age range: | Rhaetian Age (TR) — Sinemurian Age (JS) | ||
| Lithological Description: | Grey, variably calcareous and silty, blocky or fissile mudstone with thin beds of argillaceous limestone (bioclastic or micritic) and calcareous siltstone, particularly near base and in upper part, which is ferruginous in the type area. | ||
| Definition of Lower Boundary: | Where lowest grey mudstone (may be laminated) of the Lias Group rests with sharp contact on bluish and greenish grey to (less commonly) reddish brown mudstone of the Cotham Member (Lilstock Formation, Penarth Group) or on grey porcellanous limestone of the Langport Member (Lilstock Formation, Penarth Group) where locally present. | ||
| Definition of Upper Boundary: | In type area, at top of Frodingham Ironstone (Gaunt, G D, Fletcher, T P and Wood, C J, 1992); elsewhere, at erosive base of thin pebbly ferruginous oolite (Glebe Farm Bed), which marks the base of the Charmouth Mudstone Formation. | ||
| Thickness: | To c.128m | ||
| Geographical Limits: | East Midlands Shelf (north) (Leicester to Market Weighton). | ||
| Parent Unit: | Lias Group (LI) | ||
| Previous Name(s): | Ferruginous Limestone Series [Obsolete Name and Code: Use SMD]
(-4887)
Scunthorpe Mudstones Formation [Obsolete Name and Code: Use SMD] (-3685) Hydraulic Limestones [Obsolete Name And Code: See SMD, BNT, ELL] (HYDL) Angulata Clays [Obsolete Name and Code: Use SMD, BNBM] (-2626) Bucklandi Clays [Obsolete Name and Code: Use SMD] (-2431) Scunthorpe Mudstones [Obsolete Name and Code: Use SMD] (-1189) Granby Limestones [Obsolete Name and Code: Use GRBL, SMD] (-3440) |
||
| Alternative Name(s): | none recorded or not applicable | ||
| Stratotypes: | |||
| Type Area | North Lincolnshire and Humberside. Gaunt, G D, et al, 1992. | ||
| Reference Section | Borehole F/B5, Fulbeck, Lincolnshire (SK95SW/17) 4.58-117.65m depth. Brandon, A, Sumbler, M G and Ivimey-Cook, H C, 1990. See also Cox, B M, et al, 1999 for additional reference sections. | ||
| Type Section | British Geological Survey Blyborough Borehole, Blyborough, Lincolnshire (SK99SW/79) c.51.57-139.5m depth. Gaunt, G D, Fletcher, T P and Wood, C J, 1992. | ||
| Reference Section | Fulbeck Airfield Borehole F/B1 (SK85SE/25), depths 0 to 100.9m. | ||
| Reference(s): | |||
| Brandon, A, Sumbler, M G, and Ivimey-Cook, H C. 1990. A revised lithostratigraphy for the Lower and Middle Lias (Lower Jurassic) east of Nottingham, England. Proceedings of the Yorkshire Geological Society, Vol. 48, 121-141. | |||
| 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. | |||
| Cox, B M, Sumbler, M G, and Ivimey-Cook, H C. 1999. A Formational framework for the Lower Jurassic of England and Wales (Onshore Area). British Geological Survey Research Report No. RR/99/01. | |||
| 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. | |||
| 1:50K maps on which the lithostratigraphical unit is found, and map code used: | |||
| E127 E080 E089 E126 E102 E142 | |||