The BGS Lexicon of Named Rock Units — Result Details

Esk Pike Sandstone Formation

Computer Code: ESP Preferred Map Code: EsP
Status Code: Full
Age range: Caradoc Series (O4) — Caradoc Series (O4)
Lithological Description: In type area, laminated volcaniclastic mudstone and siltstone ("hornstone") with interbeds of volcaniclastic sandstone and eutaxitic lapilli tuff. Becoming massive bedded volcaniclastic sandstone with intercalations of volcaniclastic breccia, tuff and lapilli-tuff to the east.
Definition of Lower Boundary: Base of bedded volcaniclastic sedimentary rock sequence, unconformably overlying Lincomb Tarns Tuff Formation (dacitic lapilli-tuff).
Definition of Upper Boundary: Not seen in type area, but around Hellvellyn it is defined by the base of various overlying formations, including the Middle Dodd Dacite, Deepdale and Helvellyn formations.
Thickness: 170m in Central Fells, reaching 200m in the Helvellyn area
Geographical Limits: Esk Pike - Great End - Alton Crags; Easdale, Helvellyn, Scandale, Grisedale and Hartsop Dodd, Cumbria.
Parent Unit: Borrowdale Volcanic Group (BVG)
Previous Name(s): Esk Pike Formation (-2790)
Esk Pike Hornstone (-895)
Alternative Name(s): none recorded or not applicable
Stratotypes:
Reference Section  Wythburn Fells 
Reference Section  Calf Cove (Rydal Head) 
Reference Section  Black Crag (Rydal Head) 
Type Area  Summit of Esk Pike. 
Reference(s):
McConnell, B J, 1993. The Lincomb Tarns and Esk Pike formations. British Geological Survey Technical Report, WA/93/44. 
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. 
Hartley, J J. 1932. The Volcanic and other Igneous rocks of Great and Little Langdale, Westmorland: with notes on the Tectonics of the district. Proceedings of the Geologists' Association, Vol.43, p.32-69. 
Oliver, R L, 1961. The Borrowdale Volcanic and associated rocks of the Scafell area, English Lake District. Quarterly Journal of the Geological Society of London, Vol 117, p. 377-417 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
E038 E029 E030 E039