The BGS Lexicon of Named Rock Units — Result Details

Crosby Thwaite Formation [Obsolete Name And Code: Subsumed Within WNY]

Computer Code: CYT Preferred Map Code: notEntered
Status Code: Index Level
Age range: Caradoc Series (O4) — Caradoc Series (O4)
Lithological Description: Thin to thick-bedded andesitic tuffs.
Definition of Lower Boundary: Base defined by incoming of bedded tuffs.
Definition of Upper Boundary: Top defined by overlying formation (rhyodacitic lapilli tuffs).
Thickness: 200 metres, thins and wedges out to west-south-west. (West of Holehouse Gill).
Geographical Limits: Not defined.
Parent Unit: Borrowdale Volcanic Group (BVG)
Previous Name(s): none recorded or not applicable
Alternative Name(s): Whorneyside Tuff Formation
Type Area  Unnamed locality as SD 195 962, 1200m northnortheast of Crosbythwaite Farm. Sheet 38 (Ambleside), Ordnance Survey Sheet 96, (South Lakeland). 
none recorded or not applicable
1:50K maps on which the lithostratigraphical unit is found, and map code used:
none recorded or not applicable