The BGS Lexicon of Named Rock Units — Result Details

Rugby Member

Computer Code: RLS Preferred Map Code: RLs
Status Code: Full
Age range: Hettangian Age (JH) — Sinemurian Age (JS)
Lithological Description: Alternating grey, argillaceous limestones and mudstones.
Definition of Lower Boundary: Conformable on Saltford Shale Member - placed at base of an argillaceous limestone above which such limestones are common; at type section boundary placed at limestone below Bed 8 of Clements (1977).
Definition of Upper Boundary: Placed at top of highest limestone of the limestone/mudstone sequence. At the type section, placed at Bed 53c of Clements (1977).
Thickness: 36m at type section; up to 40m elsewhere.
Geographical Limits: Central and southern Midlands.
Parent Unit: Blue Lias Formation (BLI)
Previous Name(s): Lima Beds [Obsolete Name and Code: Use RLS] (-4865)
Plagiostoma Beds [Obsolete Name and Code: Use RLS] (-4866)
Blue Lias [Obsolete Code: Use BLI] (BLS)
Alternative Name(s): none recorded or not applicable
Stratotypes:
Reference Section  Harbury Quarry section and borehole (Brewster, 1978; Old et al, 1987). 
Type Section  Rugby Portland Cement Company's Parkfield Road Quarry, Rugby (Clements, 1977). 
Reference Section  Long Itchington Quarry (Clements, 1975). 
Reference(s):
Old R A, Hamblin, R J O, Ambrose, K, and Warrington G. 1991. Geology of the country around Redditch. Memoir of the British Geological Survey, Sheet 183 (England and Wales). 
Donovan, D T. 1956. The zonal stratigraphy of the Blue Lias around Keynsham, Somerset. Proceedings of the Geologists' Association, Vol.66, p. 182-212. 
Brewster, J, 1978. Harbury Quarry Borehole. Report of the Institute of Geological Sciences, No. 77/10. 
Clements, R G, (Editor) 1975. Report on the geology of Long Itchington Quarry, Leicester. Department of Geology, Leicester University. 
Clements, R G, (Editor) 1977. Report on the geology of Parkfield Road Quarry, Rugby. Department of Geology, Leicester University, p.54. 
Old, R A, Sumbler, M G and Ambrose, K, 1987. Geology of the country around Warwick. Memoir of the British Geological Survey, Sheet 184 (England and Wales). 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
E183 E169 E199 E264