The BGS Lexicon of Named Rock Units — Result Details

Airy's Bridge Tuff Formation

Computer Code: AIB Preferred Map Code: AiB
Status Code: Full
Age range: Caradoc Series (O4) — Caradoc Series (O4)
Lithological Description: Massive, white to pink weathered eutaxitic and parataxitic rhyolitic tuffs and lapilli-tuffs, with some intercalated units of pyroclastic breccia and widespread beds of laminated tuff. Some component units are markedly garnetiferous.
Definition of Lower Boundary: Base of rhyolitic pyroclastic rocks. Unconformable on slumped surface of Whorneyside Tuff Formation and locally conformable and interbedded with the Whorneyside Tuff Formation. In places directly on the Birker Fell Andesite Formation.
Definition of Upper Boundary: Defined by the base of the overlying formations that comprise a mixed succession of bedded pyroclastic rocks and volcaniclastic sandstones including: Lingmell Formation in the Central Fells, and the Duddon Hall Formation in the Coniston and Ulpha areas.
Thickness: 0 - 1010m.
Geographical Limits: Scafell - Crinkel Crags area to Borrowdale and Thirlmere, Wasdale, Coniston Fells, Duddon Valley to Stainton Fell, Cumbria.
Parent Unit: Borrowdale Volcanic Group (BVG)
Previous Name(s): Worm Crag Formation [Obsolete Name: Rocks Now Included In WNY And AIB] (WCF)
Airy's Bridge Group (-4423)
Airy's Bridge Formation (-636)
Alternative Name(s): none recorded or not applicable
Stratotypes:
Type Area  Long Top to Crinkle Crags. 
Reference(s):
Millward, D, Johnson, E W, Beddoe-Stephens, B, Young, B, Kneller, B C, Lee, M K, Fortey, N J, Allen, P M, Branney, M J, Cooper, D C, Hirons, S, Kokelaar, B P, Marks, R J, McConnell, B J, Merritt, J W, Molyneux, S G, Petterson, M G, Roberts, B, Rundle, C C, Rushton, A W A, Scott, R W, Soper, N J and Stone, P. 2000. Geology of the Ambleside district. Memoir of the British Geological Survey, England and Wales, Sheet 38. 
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 
Branney, M J, Davis, N C, Kokalaar, B P and McConnell, B J. 1993. The Airy's Bridge Formation in the central Fells. British Geological Survey Technical Report WA/93/41 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
E038 E029