The BGS Lexicon of Named Rock Units — Result Details

Chester Pebble Beds Formation [Obsolete Name And Code Use: CHES]

Computer Code: CPB Preferred Map Code: CPB
Status Code: Pending Upgrade
Age range: Early Triassic Epoch (TE) — Early Triassic Epoch (TE)
Lithological Description: Sandstone, fine- to coarse-grained, commonly pebbly, with conglomerates and sporadic siltstones; cross-stratified.
Definition of Lower Boundary: Drawn at base of sequence dominated by sandstones containing pebbles and conglomerates; pebbles do not have a local derivation. Conformable on the Kinnerton Formation or unconformable on Palaeozoic rocks.
Definition of Upper Boundary: Transition at base of Wilmslow Sandstone Formation.
Thickness: <90m - >220m
Geographical Limits: Cheshire Basin.
Parent Unit: none recorded or not applicable
Previous Name(s): BUNTER PEBBLE BEDS (BNP)
Alternative Name(s): none recorded or not applicable
Stratotypes:
Reference Section  Railway cutting (North Wales Line). Northgate Street traffic interchange to Northgate Stadium. 
Type Area  Town of Chester and vicinity (sites in Earp, and Taylor, 1986). 
Reference Section  Collinge Wood Quarry (500m east of Backford Bridge where the A41 crosses the canal). 
Reference(s):
Earp, J R and Taylor, B J, 1986. Geology of the country around Chester and Winsford. Memoir of the British Geological Survey, Sheet 109 (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. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
E123 E121 E109 E151 E137 E096