| Computer Code: |
UMM |
Preferred Map Code: |
UMM |
| Status Code: |
Pending Upgrade |
| Age range: |
Wenlock Epoch (SW)
— Wenlock Epoch (SW) |
| Lithological Description: |
Calcareous siltstone, dark grey to black mudstone and irregular mottled mudstone. Shelly fauna. Massively bedded. |
| Definition of Lower Boundary: |
Contrasts with the ribbon-banded silty mudstones of the Nantglyn Flags. |
| Definition of Upper Boundary: |
Contrasts with the ribbon-banded silty mudstones of the Nantglyn Flags. |
| Thickness: |
12 - 64m |
| Geographical Limits: |
Not defined. |
| Parent Unit: |
Nantglyn Flags Formation (NGF)
|
| Previous Name(s): |
Mottled Mudstones [Obsolete Name and Code: Use UMM, LMM]
(-2294)
|
| Alternative Name(s): |
none recorded or not applicable
|
| Stratotypes: |
| none recorded or not applicable |
| Reference(s): |
| 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. |
| 1:50K maps on which the lithostratigraphical unit is found, and map code used: |
|
E120
E094
E107
|
