| Computer Code: |
CIFD |
Preferred Map Code: |
notEntered |
| Status Code: |
Full |
| Age range: |
Asturian Substage (CAS)
— Stephanian Stage (CS) |
| Lithological Description: |
Mainly grey mudstone and siltstone, with some reddening, coal and sandstone. The lower part of the succession is dominantly argillaceous and included relatively thick coals, including the Brazilly and Crow coals. The middle part of the member includes the Serridge Sandstone, which passes from exclusively sandstone in the north to interbedded sandstone and shale to the south. The upper argillaceous part of the member includes further coal seams (Woodgreen Coals). |
| Definition of Lower Boundary: |
Taken at the base of the Brazilly Coal, which rests conformably upon thick-bedded, coarse-grained sandstone of the Coleford Member of the Pennant Sandstone Formation. |
| Definition of Upper Boundary: |
The member is the youngest unit within the Forest of Dean outlier. The top of the member is not proved. |
| Thickness: |
From 180 m thick in the north, to 300 m in the south of the Forest of Dean Coalfield. |
| Geographical Limits: |
Restricted to the central part of the Forest of Dean outlier (SO 60). |
| Parent Unit: |
Grovesend Formation (GDB)
|
| Previous Name(s): |
Cinderford Formation [Obsolete Name and Code: Use CIFD]
(-3300)
|
| Alternative Name(s): |
none recorded or not applicable
|
| Stratotypes: |
| Partial Type Section |
The disused Oakenhill railway cutting, 1.5 km east of Parkend: Overgrown section in the lower, argillaceous part of the member. Cleal & Thomas, 1996. |
| Reference(s): |
| Trotter, F M, 1942. Geology of the Forest of Dean and Iron-ore Field. Memoir of the Geological Survey of Great Britain. |
| Waters, C N, Barclay, W J, Davies, J R and Waters, R A. In press. Stratigraphical framework for Carboniferous successions of Southern Great Britain (Onshore). British Geological Survey Research Report, RR/05/06. |
| Cleal, C and Thomas, B A. 1996. British Upper Carboniferous stratigraphy. Geological conservation review series No. 11. [London: Chapman and Hall]. |
| Waters, C N, Waters, R A, Barclay, W J, and Davies, J R. 2009. Lithostratigraphical framework for Carboniferous successions of Southern Great Britain (Onshore). British Geological Survey Research Report, RR/09/01. 184pp. |
| 1:50K maps on which the lithostratigraphical unit is found, and map code used: |
|
E233
|
