| 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 [Obsolete Name and Code: Use DH, DBT]
(-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
|
