The BGS Lexicon of Named Rock Units — Result Details

Cockley How Tuff Member

Computer Code: CKY Preferred Map Code: Cky
Status Code: Full
Age range: Caradoc Series (O4) — Caradoc Series (O4)
Lithological Description: Dacitic ignimbrite in the form of massive lapilli-tuff but with a lithologically distinct basal layer of parataxitic lapilli-tuff.
Definition of Lower Boundary: Most distinct where basal parataxitic lapilli-tuff rests on bedded sandstone (Deepdale Sandstone Formation).
Definition of Upper Boundary: Indistinct, but overlain by bedded sandstone (Deepdale Sandstone Formation).
Thickness: 45m (maximum)
Geographical Limits: Confined to areas south and east of Deepdale Park, Deepdale, northeastern Lake District (between Grasmere and Patterdale).
Parent Unit: Deepdale Sandstone Formation (DPD)
Previous Name(s): none recorded or not applicable
Alternative Name(s): none recorded or not applicable
Stratotypes:
Reference Section  Crags adjacent to Cockley How, 1-8km south-south-west of Deepdale. 
Reference(s):
Woodhall, D G, 1998. The geology of the Wythburn, Thirlmere and Fairfield areas of the north-east Lake District. British Geological Survey Technical Report WA/98/07. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
E030 E029