The BGS Lexicon of Named Rock Units — Result Details

Crawford Group

Computer Code: CRFD Preferred Map Code: CRFD
Status Code: Full
Age range: Arenig Series (OR) — Caradoc Series (O4)
Lithological Description: Lava, chert, tuff and mudstone succession.
Definition of Lower Boundary: Faulted.
Definition of Upper Boundary: Thought to be overlain by Glenkiln Shale Formation of the Moffat Shale Group.
Thickness: To about 190m
Geographical Limits: The Southern Uplands of Scotland, and Longford Down in Northern Ireland.
Parent Unit: Not Applicable (-)
Previous Name(s): none recorded or not applicable
Alternative Name(s): none recorded or not applicable
Stratotypes:
Type Section  Glencaple Burn, Crawford, Lanarkshire. 
Reference(s):
Floyd, J D, 1996. Lithostratigraphy of the Ordovician rocks in the Southern Uplands: Crawford Group, Moffat Shale Group, Leadhills Supergroup. Transactions of the Royal Society of Edinburgh: Earth Sciences, Vol.86, 153-165. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
S015 S015 S008 S016 S025 S017 S024