| Computer Code: |
DYL |
Preferred Map Code: |
notEntered |
| Status Code: |
Full |
| Age range: |
Holkerian Substage (CQ)
— Asbian Substage (CR) |
| Lithological Description: |
[Obsolete: use CLWYD]
Predominantly limestones with bands of carbonaceous mudstone. Lowest beds contain cherts and dolomites and dolomitic limestone. |
| Definition of Lower Boundary: |
Drawn at the base of the Dyserth Group where cyclic brown limestone conformably rests upon arenaceous limestone of the Basement Beds. |
| Definition of Upper Boundary: |
Drawn at the conformable upward passage of brown grey and white limestones of the Dyserth Group unconformably overlain by darker fine-grained limestones of the Teila Formation. |
| Thickness: |
500 metres approx. |
| Geographical Limits: |
Confined to the north Wales coastal area of Great Orme, Little Orme, Llanddulas and Prestatyn. |
| Parent Unit: |
none recorded or not applicable
|
| Previous Name(s): |
none recorded or not applicable
|
| Alternative Name(s): |
none recorded or not applicable
|
| Stratotypes: |
| Type Area |
Great Orme. |
| Reference(s): |
| George, T N, Johnson, G A L, Mitchell, M, Prentice, J E, Ramsbottam, W H C, Sevastopulo, G D, and Wilson, R B. 1976. A correlation of the Dinantian rocks of the British Isles. Special Report of the Geological Society of London, No. 7. |
| Definition not published. |
| Warren, P T, Price, D, Nutt, M J C and Smith, E G. 1984. Geology of the country around Rhyl and Denbigh. Memoir for 1:50 000 geological sheets 95 and 107 and parts of sheets 94 and 106. |
| Neaverson, E. 1930. The Carboniferous rocks around Prestatyn, Dyserth, and Newmarket (Flintshire). Proceedings of the Geological Society of Liverpool, Vol.15, 179-212. |
| 1:50K maps on which the lithostratigraphical unit is found, and map code used: |
|
E094
|
