| Computer Code: |
BMS |
Preferred Map Code: |
BmS |
| Status Code: |
Index Level |
| Age range: |
Early Triassic Epoch (TE)
— Anisian Age (TA) |
| Lithological Description: |
[Obsolete: use HEY] Sandstones, red, brown and grey, commonly pebbly or conglomeratic at the bases of beds, interbedded with red and brown siltstones and mudstones. |
| Definition of Lower Boundary: |
Disconformable on Wildmoor Formation or older formations; taken at base of lowest pebbly bed with chips of unweathered feldspar (Wills, 1976 p.37,99) at outcrop in type area. |
| Definition of Upper Boundary: |
Transitional at base of Mercia Mudstone Group. |
| Thickness: |
0->300m (Redditch area), 15-40m (Stoke-on-Trent area), c.500m (Worcester area). |
| Geographical Limits: |
Stafford and Worcester basins. |
| Parent Unit: |
none recorded or not applicable
|
| Previous Name(s): |
Keuper Sandstone, Lower [Obsolete name and code, use HEY]
(-709)
|
| Alternative Name(s): |
none recorded or not applicable
|
| Stratotypes: |
| Type Area |
Bromsgrove, north Worcestershire (definition of Warrington, et al, 1980); basal Burcot Breccia exposures in Wills, 1976, p 37; other localities, Old, et al, 1991, p 18-30. |
| Reference Section |
Metropolitan-Cammel Ltd, Saltley, Birmingham borehole 100/1944 (Wills, 1970). 25.9-217.2m in depth. (Wills,1976, p 134) (85ft-712ft 6in). |
| Reference Section |
Sugarbrook No 1 Borehole, Stoke Prior, near Bromsgrove, depth 33.5-281.8m (SO 96NE/1) (Wills, 1970; 1976, p 107). |
| Reference(s): |
| Wills, L J. 1970. The Triassic succession in the central Midlands in its regional setting. Quarterly Journal of the Geological Society of London, Vol.126, 225-285. |
| Wills, L J. 1976. The Trias of Worcestershire and Warwickshire. Report of the Institute of Geological Sciences, No.76/2. |
| Ambrose, K, Hough, E, Smith, N J P, and Warrington, G. 2014. Lithostratigraphy of the Sherwood Sandstone Group of England, Wales and south-west Scotland. British Geological Survey Research Report RR/14/01. |
| 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). |
| Warrington, G, Audley-Charles, M G, Elliott, R E, Evans, W B, Ivimey-Cook, H C, Kent, P E, Robinson, P L, Shotton, F W and Taylor, F M. 1980. A correlation of the Triassic rocks in the British Isles. Special Report of the Geological Society of London, No.13. |
| Howard, A S, Warrington, G, Ambrose, K, and Rees, J G. 2008. A formational framework for the Mercia Mudstone Group (Triassic) of England and Wales. British Geological Survey Research Report, RR/08/04. |
| 1:50K maps on which the lithostratigraphical unit is found, and map code used: |
|
E216
E155
E184
E183
E123
E140
E199
E139
E154
E201
E217
E236
E167
E141
|
