The BGS Lexicon of Named Rock Units — Result Details

Barrow Tuff Member

Computer Code: BART Preferred Map Code: BarT
Status Code: Full
Age range: Caradoc Series (O4) — Caradoc Series (O4)
Lithological Description: Dacitic lapilli-tuff, pink-weathered, foliated, with autobreccia at top.
Definition of Lower Boundary: Base of pyroclastic flow deposit, usually overlies volcaniclastic sandstone and locally sits directly on the Wrayslack Tuff Member in the Waberthwaite Formation.
Definition of Upper Boundary: Top of pyroclastic flow deposit that characteristically has a rheomorphic autoclastic breccia; Duddon Bridge Tuff Member above.
Thickness: 230-270m
Geographical Limits: Between Beckstone (SD 183 903) and Duddon Bridge (SD 197 881), near Broughton in Furness, Cumbria.
Parent Unit: Waberthwaite Tuff Formation (WB)
Previous Name(s): none recorded or not applicable
Alternative Name(s): none recorded or not applicable
Stratotypes:
Type Area  On Barrow, 1.2km north west of Duddon Bridge, Cumbria. 
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. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
E048