The BGS Lexicon of Named Rock Units — Result Details

Barr Limestone Formation

Computer Code: BLZ Preferred Map Code: BL
Status Code: Full
Age range: Sheinwoodian Age (SS) — Sheinwoodian Age (SS)
Lithological Description: Grey, micritic limestone interbedded with grey mudstone containing large calcareous nodules.
Definition of Lower Boundary: Gradational increase in thickness and number of limestone beds from underlying Buildwas Formation.
Definition of Upper Boundary: Gradational decrease in thickness and number of limestone beds to overlying Coalbrookdale Formation.
Thickness: 9-10m at Walsall
Geographical Limits: South Staffordshire.
Parent Unit: Not Applicable (-)
Previous Name(s): Barr Limestone (-707)
Woolhope Limestone (-1363)
Alternative Name(s): none recorded or not applicable
Stratotypes:
Type Area  Series of overgrown quarries from Cuckoo's Nook to Daisy Bank, Hay Head, Great Barr. 
Reference Section  Walsall Co-operative Society Borehole; 762' to 795'6" (SP09NW/33) 
Reference(s):
Basset, M G, 1974. Review of the stratigraphy of the Wenlock Series of the Welsh Borderlands and South Wales. Palaeontology, 17, 745-777. 
Barrow, G, Gibson, W, Cantrill, T C, Dixon, E E L and Cunningham, C H, 1919. The geology of the country around Lichfield. Memoir of the Geological Survey of Great Britain. 
Cocks, L R M, Holland, C H, Rickards, R B and Strachan, I, 1971. A correlation of Silurian rocks in the British Isles. Geological Society of London, Special Report No.1. 
Butler, A J, 1937. On Silurian and Cambrian rocks encountered in a deep boring at Walsall, South Staffordshire, Geological Magazine, 74, 241-257. 
Whitehead, T H and Eastwood, T, 1927. The geology of the southern part of the South Staffordshire Coalfield. Memoir of the Geological Survey of Great Britain. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
E168 E154