| Computer Code: |
FGR |
Preferred Map Code: |
FGr |
| Status Code: |
Index Level |
| Age range: |
Abereiddian Stage (O2)
— Caradoc Series (O4) |
| Lithological Description: |
[Obsolete: use BFA] Dacite lavas or sills with intercalated volcanogenic sandstone. |
| Definition of Lower Boundary: |
Unconformity or thrust fault at base of Borrowdale Volcanic Group on Skiddaw Group. |
| Definition of Upper Boundary: |
Non-sequence:- at top of dacite succession below the Nettle Crags Tuff Formation. |
| Thickness: |
100-150m |
| Geographical Limits: |
Fell Green - Bootle Fell, between the Skiddaw Group and the Eskdale Granodiorite. |
| Parent Unit: |
none recorded or not applicable
|
| Previous Name(s): |
Not previously named, included as part of Nettle Crags Tuffs and Lavas [Obsolete Name and Code: Use FGR]
(-4649)
|
| Alternative Name(s): |
none recorded or not applicable
|
| Stratotypes: |
| Type Area |
Near Fell Green, Bootle, Cumbria; between Crookley Beck and Nettle Crags. |
| Reference(s): |
| British Geological Survey. 1994. Black Combe and Bootle, SD18NW, Solid and Drift 1:10 000. (Keyworth, Nottingham: British Geological Survey.) |
| Mathieson, N A, 1986 Geology, structure and geochemistry of the Ordovician volcanic succession in south west Cumbria. Unpublished Ph.D. thesis, University of Sheffield. |
| 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: |
| none recorded or not applicable |
