| Computer Code: |
NBG |
Preferred Map Code: |
notEntered |
| Status Code: |
Index Level |
| Age range: |
Ludlow Epoch (SU)
— Ludlow Epoch (SU) |
| Lithological Description: |
[Obsolete] Fine grained uncleaved sandstones (often deformed) and roughly cleaved sandy shales. |
| Definition of Lower Boundary: |
Drawn at the base of the Nant-Y-Bache Group where it rests conformably on thin-bedded shales and mudstoness of the Glyn-Dyfrdwy Group. |
| Definition of Upper Boundary: |
Drawn at the conformable upward passage from its uncleaved sandstones and shales to thin-bedded flaggy shales with siltstones of the Vivod Group. |
| Thickness: |
300 metres approx. |
| Geographical Limits: |
Llangollen, north Wales. |
| Parent Unit: |
none recorded or not applicable
|
| Previous Name(s): |
none recorded or not applicable
|
| Alternative Name(s): |
Elwy Group [Obsolete: use EY]
|
| Stratotypes: |
| Type Area |
Llangollen, Clwyd. |
| Reference(s): |
| Wills, L J and Smith, B, 1922. The Lower Palaeozoic Rocks of the Llangollen district with special reference to Tectonics. Quarterly Journal of the Geological Society, Vol.78, p.176-226. |
| Wedd, C B, Smith, B and Wills, L J. 1927. The geology of the country around Wrexham, Part 1. Lower Palaeozoic and Lower Carboniferous rocks. Memoir of the Geological Survey of Great Britain. [London: HMSO.] 179pp. |
| 1:50K maps on which the lithostratigraphical unit is found, and map code used: |
| none recorded or not applicable |
