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: |
Reference Section |
Steeple Aston Borehole, SP42NE12, complete thickness of the member from 424.66 m to 322.44 m depth. Poole, 1977. |
Type Section |
Apley Barn Borehole, SP31SW3, complete thickness of the member from 792.4 m to 587.8 m depth. Poole, 1969. |
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. |
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: |
E236
|