The BGS Lexicon of Named Rock Units — Result Details

Witney Coal Member

Computer Code: WTC Preferred Map Code: notEntered
Status Code: Full
Age range: Asturian Substage (CAS) — Asturian Substage (CAS)
Lithological Description: A grey coal-bearing succession, with typical upward-coarsening cycles from mudstone to sandstone, capped by a seatearth and a coal.
Definition of Lower Boundary: Seen in the type section as a grey mudstone with basal coal of the Witney Coal Member overlies conformably pale greenish grey, rooted, fine-grained sandstone of the Pennant Sandstone Formation.
Definition of Upper Boundary: Seen in the type section as a greyish blue, brown, yellow and red mudstone of the Crawley Member, overlies conformably dark grey, carbonaceous mudstone of the Witney Coal Member.
Thickness: Maximum thickness of 83 m in the type section.
Geographical Limits: Widespread in the Oxfordshire Coalfield, but proved only in the subsurface, and in a single borehole, Harwell No. 3 SU48NE92, (SU 46801 86441), in the Berkshire Coalfield (Foster et al., 1989).
Parent Unit: Grovesend Formation (GDB)
Previous Name(s): Witney Coal Group (-2541)
Witney Coal Formation (-3144)
Alternative Name(s): none recorded or not applicable
Type Section  Apley Barn Borehole SP31SW3, complete thickness of the member from 875.4 m to 792.4 m depth. Poole, 1969. 
Reference Section  Steeple Aston Borehole SP42NE12, complete thickness of the member from 467.4 m to 424.66 m depth. .Poole, 1977. 
Reference Section  Upton Borehole, SP21SW1, from 1049.88 to 928.29 m. Worssam, 1963; Poole, 1977. 
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. 
Poole E G. 1977. Stratigraphy of the Steeple Aston Borehole, Oxfordshire. Bulletin of the Geological Survey of Great Britain, Vol. 57, 1-85. 
Foster D, Holliday D W, Jones C M, Owens B and Walsh A. 1989. The concealed Upper Palaezoic rocks of Berkshire and South Oxfordshire. Proceedings of the Geologists' Association, Vol. 100, 395-407. 
Poole E G. 1969. The stratigraphy of the Geological Survey Apley Barn Borehole, Witney, Oxfordshire. Bulletin of the Geological Survey of Great Britain, Vol. 29, 1-66. 
1:50K maps on which the lithostratigraphical unit is found, and map code used: