| Computer Code: |
PMR |
Preferred Map Code: |
notEntered |
| Status Code: |
Full |
| Age range: |
Duckmantian Substage (CB)
— Duckmantian Substage (CB) |
| Lithological Description: |
A yellow, cross-bedded sandstone, with subordinate mudstone. Pebbly sandstone noted at the base of the unit at Bradley Hall Colliery, Standish borehole SD51SE/53. |
| Definition of Lower Boundary: |
The lower boundary is believed to be partly erosional. The base is taken at a sharp, well-defined surface which is erosional in parts, seperating mudstones below the boundary and sandstones and pebbly sandstones above the boundary. The base is taken at the base of the first sandstone-dominated unit above the higher Florida Coal in the Runcorn [SJ 50 80] and the south Wigan [SD 00 60] areas, and the base of the first sandstone unit above the Pemberton 5' Coal in the North Wigan [SD 60 10] area, and the base of the first sandstone unit above the Bargain Delf Coal at Bradley Hall Colliery (SD 5730 1106). |
| Definition of Upper Boundary: |
The upper boundary is taken at the base of the mudstone, coal and fireclay-dominated succession of the Pennine Middle Coal Measures Formation above sandstones of the Pemberton Rock |
| Thickness: |
Up to 61 m thick. |
| Geographical Limits: |
Adlington [SD 59 12] to Rainhill [SJ 49 91]. |
| Parent Unit: |
Pennine Middle Coal Measures Formation (PMCM)
|
| Previous Name(s): |
none recorded or not applicable
|
| Alternative Name(s): |
none recorded or not applicable
|
| Stratotypes: |
| Type Section |
Top and base of the unit are proven at Bradley Hall Colliery, Engine Pit [SD51SE/53], from 462 feet 2 inches to 641 feet 2 inches below ground level. Jones et al. 1938. |
| Reference(s): |
| Jones, R C B, Tonks, L H and Wright, W B, 1938. Wigan District. Memoir of the Geological Survey of Great Britain. England and Wales Sheet 84. |
| 1:50K maps on which the lithostratigraphical unit is found, and map code used: |
|
E084
E097
|
