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. 
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. 
Type Area  Warwickshire Coalfield between Over Whitacre and Baxterley (poor exposures). 
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. 
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). 
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). 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
E169 E154