The BGS Lexicon of Named Rock Units — Result Details

Cropthorne Sand And Gravel Member

Computer Code: CRTD Preferred Map Code: notEntered
Status Code: Full
Age range: Pleistocene Epoch (QP) — Pleistocene Epoch (QP)
Lithological Description: Predominantly cold phase sands and gravels that underlie the Avon Fourth Terrace of Tomlinson (1925) and of BGS maps. Dominated by clasts of "Bunter" quartz/quartzite lithologies with subordinate flint. Locally includes the organic Ailstone Bed, assigned to MIS 7, at its base. Probably equates with the Kidderminster Station Member of the Severn Valley Formation. (See also Compiler's notes under Supplementary Information.)
Definition of Lower Boundary: Unconformable, commonly channelled base, resting on Wolston Formation or Baginton Formation in upper Avon, or farther downstream (beyond Coventry), on Lower Jurassic or Triassic bedrock.
Definition of Upper Boundary: Ground surface.
Thickness: 0 to 6m
Geographical Limits: Avon Valley, Rugby to Tewkesbury (BGS Sheets 183, 184, 199, 200, 201, 216).
Parent Unit: Warwickshire Avon Valley Formation (AVON)
Previous Name(s): Ailstone Member (-2121)
Cropthorne Member (-2122)
No.4 Terrace [Deposits] (-2123)
Fourth Terrace Deposits (-3961)
Fourth Terrace [Deposits] (-3962)
Avon Fourth Terrace [Deposits] (-2724)
Cropthorne Terrace Deposits (-2725)
Fourth Or Ailstone Terrace [Deposits] (-2726)
Alternative Name(s): none recorded or not applicable
Stratotypes:
Type Section  Borehole 2 at Cropthorne, near Evesham, Worcestershire. Bowen, 1999, based on Maddy et al. 1991. 
Reference(s):
Maddy, D, Keen, D H, Bridgland, D R and Green, C P. 1991. A revised model for the Pleistocene development of the River Avon, Warwickshire. Journal of the Geological Society of London, Vol.148, 473-484. 
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). 
Worssam, B C, Ellison, R A and Moorlock, B S P. 1989. Geology of the country around Tewkesbury. Memoir of the British Geological Survey, Sheet 216 (England and Wales). 
Bowen, D Q. 1999. A revised correlation of Quaternary deposits in the British Isles. Geological Society Special Report, No. 23. 
Barclay, W J, Ambrose K, Chadwick, R A and Pharaoh, T C. 1997. Geology of the country around Worcester. Memoir of the British Geological Survey, Sheet 199 (England and Wales). 
Edmonds, E A, Poole, E G and Wilson, V. 1965. Geology of the country around Banbury and and Edge Hill. Memoir of the Geological Survey of Great Britain, Sheet 201 (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). 
Shotton, F W. 1953. The Pleistocene deposits of the area between Coventry, Rugby and Leamington and their bearing on the topographic development of the Midlands. Philosophical Transactions of the Royal Society of London, Vol.B237, 209-260. 
Tomlinson, M E. 1925. The river terraces of the lower valley of the Warwickshire Avon. Quarterley Journal of the Geological Society of London. Vol.81, 137-169. 
Williams, B J and Whittaker, A. 1974. Geology of the country around Stratford-upon-Avon and Evesham. Memoir of the Geological Survey of Great Britain Sheet 200 (England and Wales). 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
E183 E184 E199 E200 E201 E216