The BGS Lexicon of Named Rock Units — Result Details

Whitacre Member

Computer Code: WIT Preferred Map Code: Wit
Status Code: Full
Age range: Asturian Substage (CAS) — Stephanian Stage (CS)
Lithological Description: Red bed sequence; mudstone-dominated in lower part but increasingly arenaceous towards top. Thin Spirorbis limestones at some levels. Impersistent conglomerates in uppermost part.
Definition of Lower Boundary: Transitional. Defined in the field at the upwards change from grey measures of the Halesowen Formation to red beds. Defined on geophysical logs (in uncored boreholes) above a narrow zone of high gamma radiation.
Definition of Upper Boundary: At the top of highest mappable sandstone unit (Arley and Exhall sandstones) beneath the basal argillaceous beds of the overlying Keresley Member.
Thickness: Range 280 - 357m; mean 334m; based on geophysical well log data.
Geographical Limits: Warwickshire Coalfield (northern part) Sheet 169. Also likely to extend in the subcrop across the southern part of the Warwickshire Coalfield (Sheet 184).
Parent Unit: Salop Formation (SAL)
Previous Name(s): Includes Coventry Sandstone, (Lower Part) (-610)
Alternative Name(s): none recorded or not applicable
Stratotypes:
Reference Section  Birch Tree Farm Borehole (SP38SW/161). Top of Member (uncored) taken at 238m below surface. Base at 519.5m below surface. 
Type Area  Warwickshire Coalfield between Over Whitacre and Baxterley (poor exposures). 
Reference Section  Old quarry at Tipper's Hill Lane exposes granule to pebble grade breccio-conglomerates composed primarily of mudstone clasts. Typifies lower part of member. 
Reference(s):
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). 
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). 
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. 
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:
E169 E154