The BGS Lexicon of Named Rock Units — Result Details

Duddon Bridge Tuff Member

Computer Code: DBT Preferred Map Code: DBT
Status Code: Full
Age range: Caradoc Series (O4) — Caradoc Series (O4)
Lithological Description: Andesitic lapilli-tuff, massive.
Definition of Lower Boundary: Base of andesitic lapilli-tuff succession. Usually rests on brecciated top of Barrow Tuff Member.
Definition of Upper Boundary: Defined by base of overlying Duddon Hall Formation - parallel bedded andesitic tuff.
Thickness: c.250m excluding basaltic andesite sill (130m)
Geographical Limits: Between Ulpha Park (SD 187 910) and Duddon Bridge (SD 196 882), near Broughton in Furness, Cumbria.
Parent Unit: Waberthwaite Tuff Formation (WB)
Previous Name(s): Duddon Bridge Tuffs (-3351)
Alternative Name(s): none recorded or not applicable
Stratotypes:
Type Area  Between Barrow and Duddon Hall. 
Reference(s):
Johnson, E W, Soper, N J, Burgess, I C, Ball, D F, Beddoe-Stephens, B, Carruthers, R M, Fortey, N J, Hirons, S, Merritt, J W, Millward, D, Roberts, B, Walker, A B and Young, B. 2001. Geology of the country around Ulverston. Memoir of the British Geological Survey, England and Wales, Sheet 48. 
Mitchell, G H, 1956. (Undivided Lickle Rhyolites). The Borrowdale Volcanic Series of the Dunnerdale Fells, Lancashire. Liverpool and Manchester Geological Journal, Vol.1, p.428-449. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
E048