The BGS Lexicon of Named Rock Units — Result Details

Ashow Formation

Computer Code: AW Preferred Map Code: AW
Status Code: Full
Age range: Cisuralian Epoch (PLC) — Cisuralian Epoch (PLC)
Lithological Description: Red-brown mudstone with subordinate, but locally thick, beds of red-brown and grey-green, fine- to medium-grained sandstone.
Definition of Lower Boundary: Taken at the incoming of a thick succession of red mudstone (50 to 65m thick) above the Kenilworth Sandstone Formation.
Definition of Upper Boundary: Taken at the base of the unconformable Bromsgrove Sandstone Formation (Triassic) in the type area.
Thickness: Up to 250m in Sandy Lane and Barford boreholes.
Geographical Limits: Southern part of the Warwickshire Coalfield.
Parent Unit: Warwickshire Group (WAWK)
Previous Name(s): ASHOW GROUP
Alternative Name(s): none recorded or not applicable
Stratotypes:
Type Area  Warwick and the southern part of the Warwickshire Coalfield. The upper part of the formation around Warwick is poorly exposed, and occurs in fault-bounded inliers; as a result details of the succession and thickness are uncertain. 
Reference Section  (a). Whitemoor Brickworks, Kenilworth (Richardson and Fleet, 1926; Shotton, 1929; Old et al.,1987); lower part of formation. 
Reference Section  Cherry Orchard Brickworks, Kenilworth (Richardson and Fleet, 1926; Shotton, 1929; Old et al., 1987); lower part of formation. 
Reference Section  (b). Chesford Bridge (Old et al., 1987); sandstones in middle part of formation. 
Reference Section  (c). Guys Cliffe Chapel pit; upper part of formation. 
Reference Section  (d). Tachbrook Mallory Borehole (Richardson, 1928).(SP 36 SW/13). 
Reference Section  (e). Sandy Lane Borehole (SP 36 NW/82); from surface to base of formation at 253.8m. 
Reference(s):
Powell, J H, Chisholm, JI, Bridge, D M, Rees, J G, Glover, B W and Besly, B M. 1999. Stratigraphical framework for Westphalian to Early Permian red-bed successions of the Pennine Basin. British Geological Survey Technical Report WA/99/10. 
Bridge, D McC, Carney, J N, Lawley, R S and Rushton, A W A. 1998. Geology of the country around Coventry and Nuneaton. Memoir of the British Geological Survey, Sheet 169 (England and Wales). 
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). 
Old, R A, Bridge, D M and Rees, J G, 1990. Geology of the Coventry area. British Geological Survey Technical Report, WA/89/29 
Richardson, L. 1928. The wells and springs of Warwickshire. Memoir of the Geological Survey of Great Britain. 
Richardson, L and Fleet, W F. 1926. On sandstones with breccias below the Trias at Stratford-upon-Avon and elsewhere in south Warwickshire. Proceedings of the Geologists' Association, Vol.37, 283-305. 
Shotton, F W.1929. The geology of the country around Kenilworth (Warwickshire). Quarterly Journal of the Geological Society of London, Vol. 28, 167 - 222. 
Eastwood, T, Gibson, W, Cantrill, T C and Whitehead, T H. 1923. The geology of country around Coventry, including an account of the Carboniferous rocks of the Warwickshire Coalfield. Memoir of the Geological Survey of Great Britain, Sheet 169. (England and Wales). 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
E184