The BGS Lexicon of Named Rock Units — Result Details

Upper Coldwell Beds [Obsolete Name And Code: Use WRE]

Computer Code: UCW Preferred Map Code: UCw
Status Code: Index Level
Age range: Gorstian Age (SG) — Gorstian Age (SG)
Lithological Description: Blue-grey, finely laminated muddy siltstones with laminae of coarser siltstone. Silt laminae are more common than in the Brathay Flags and the overall grain size is slightly coarser.
Definition of Lower Boundary: Transitional, taken at junction of the laminated siltstones with more massive, cleaved, calcareous siltstones of the Middle Coldwell Beds.
Definition of Upper Boundary: Taken at the incoming of thin sandstones, producing a transition to the Coniston Grit Formation.
Thickness: c. 460 metres maximum, thins eastwards.
Geographical Limits: Not defined.
Parent Unit: Windermere Supergroup (WIN)
Previous Name(s): none recorded or not applicable
Alternative Name(s): none recorded or not applicable
Stratotypes:
Type Area  Coldwell, near Hawkshead, Cumbria (south from NY 359 010), good section seen in Kill Gill, Kentmere, Sheet 38 (Ambleside). 
Reference(s):
Marr J E. 1892. On the Wenlock and Ludlow strata of the Lake District. Geological Magazine, Vol. 9, p 534-541. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
E039