The BGS Lexicon of Named Rock Units — Result Details

Eagle Crag Sandstone Member

Computer Code: EAGC Preferred Map Code: Eag
Status Code: Full
Age range: Caradoc Series (O4) — Caradoc Series (O4)
Lithological Description: Volcaniclastic siltstone, sandstone, conglomerate and breccia in a bedded succession; intercalated subordinate units of tuff, eutaxitic lapilli-tuff and accretionary lapilli-tuff. Intruded by many peperitic andesite sills.
Definition of Lower Boundary: Taken at the base of the lowest bedded volcaniclastic rock within the sequence of volcaniclastic sedimentary rocks and associated andesite sills, resting on andesite or, locally, dacite within the Birker Fell Andesite Formation.
Definition of Upper Boundary: Defined by the base of overlying andesite sheets of the Birker Fell Andesite Formation.
Thickness: Up to 270m
Geographical Limits: From Haycock, southwest of Buttermere to the area east of Derwent Water, Cumbria
Parent Unit: Birker Fell Andesite Formation (BFA)
Previous Name(s): Eagle Crag Member (-224)
Eagle Crag Tuffs And Honister Slates (-2775)
Alternative Name(s): none recorded or not applicable
Stratotypes:
Type Area  High Stile to Comb Crags, south of Buttermere, Cumbria McConnell and Kneller, 1993 
Reference Section  Fleetwith Pike and Honister Quarries, southeast of Buttermere, Cumbria. McConnell and Kneller, 1993. 
Reference(s):
McConnell, B J and Kneller, B C, 1993. The Lower Borrowdale Volcanic Group of Ennerdale and upper Borrowdale. British Geological Survey Technical Report WA/93/38. 
Petterson, M G, Beddoe-Stephens, B, Millward, D and Johnson, E W, 1992. A pre-caldera plateau-andesite field in the Borrowdale Volcanic Group of the English Lake District. Journal of the Geological Society, London, Vol. 149, 889-906. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
E029