| Computer Code: |
CRFT |
Preferred Map Code: |
uc |
| Status Code: |
Pending Upgrade |
| Age range: |
Merioneth Series (EM)
— Merioneth Series (EM) |
| Lithological Description: |
Black, fissile, mudstone interlaminated with micaceous siltstone and very fine-grained sandstone. |
| Definition of Lower Boundary: |
Base of mudstone of above type, resting unconformably on shelly glauconitic limestone of the Lower Comley Limestones. |
| Definition of Upper Boundary: |
Not proved. |
| Thickness: |
53.75m |
| Geographical Limits: |
Lilleshall Inlier, Shropshire. |
| Parent Unit: |
Bentleyford Shales Formation (BTS)
|
| Previous Name(s): |
none recorded or not applicable
|
| Alternative Name(s): |
none recorded or not applicable
|
| Stratotypes: |
| Type Section |
Croft Borehole, Lilleshall, SJ71NW/16. |
| Reference(s): |
| Rushton, A W A, Hamblin, R J O and Strong, G E, 1988. The Croft Borehole in the Lilleshall Inlier of North Shropshire. Report of the British Geological Survey, Vol.19, No.3. |
| 1:50K maps on which the lithostratigraphical unit is found, and map code used: |
| none recorded or not applicable |
