The BGS Lexicon of Named Rock Units — Result Details

Crawley Member

Computer Code: CRW Preferred Map Code: notEntered
Status Code: Full
Age range: Asturian Substage (CAS) — Asturian Substage (CAS)
Lithological Description: Thick beds of red mudstone with common desiccation cracks, interbedded with conglomerate, grey seatearth, sandstone and mudstone and scarce thin coals
Definition of Lower Boundary: In the type section, greyish blue, brown, yellow and red mudstone of the Crawley Member overlies conformably dark grey, carbonaceous mudstone of the Witney Coal Member.
Definition of Upper Boundary: In the type section, dark grey, carbonaceous mudstone with basal coal of the Burford Coal Member, overlies conformably grey to red mudstone-dominated succession of the Crawley Member.
Thickness: Maximum thickness of 205 m in the type section.
Geographical Limits: Oxfordshire Coalfield; in the subsurface only.
Parent Unit: Grovesend Formation (GDB)
Previous Name(s): Crawley Formation (-822)
Alternative Name(s): none recorded or not applicable
Stratotypes:
Type Section  Apley Barn Borehole, SP31SW3, complete thickness of the member from 792.4 m to 587.8 m depth. Poole, 1969. 
Reference Section  Steeple Aston Borehole, SP42NE12, complete thickness of the member from 424.66 m to 322.44 m depth. Poole, 1977. 
Reference(s):
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. 
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:
E236