| Computer Code: |
ABY |
Preferred Map Code: |
ABY |
| Status Code: |
Full |
| Age range: |
Asbian Substage (CR)
— Brigantian Substage (CX) |
| Lithological Description: |
Mainly pale coloured sandstones interbedded with grey siltstones and grey to dark grey mudstones; subordinate coal, seatrock, carbonates and ironstone. |
| Definition of Lower Boundary: |
The base is drawn at the base of the lowest of the Macgregor Marine Bands (Wilson, 1974), which in the type section is the Saltoun Marine Band (McAdam and Tulloch, 1985, p22). |
| Definition of Upper Boundary: |
The top is taken at the base of the Upper Longcraig Limestone, the local equivalent of the Hurlet Limestone (Wilson, 1989). |
| Thickness: |
Spilmersford Borehole 134m. Skateraw Borehole 139m. |
| Geographical Limits: |
Midlothian (part); East Lothian; Berwickshire (part). |
| Parent Unit: |
Strathclyde Group (SYG)
|
| Previous Name(s): |
Upper Lothian Group [Obsolete Name and Code: Use ABY]
(-3789)
|
| Alternative Name(s): |
West Lothian Oil-Shale Formation
|
| Stratotypes: |
| Reference Section |
Shore section at Kilspindie, Duff,"in", McAdam and Clarkson, 1986, map 8. The formation is named after the village of Aberlady, which lies on the main outcrop. |
| Type Section |
Spilmersford Borehole NT46SE/73 between 21.64 and 155.44m depth |
| Reference Section |
Skateraw Borehole between 28.88m and 168.10m in depth. |
| Reference(s): |
| Chisholm, J I, MacAdam, A D, Brand, P J. 1989. Lithostratigraphical classification of Upper Devonian and Lower Carboniferous rocks in the Lothians. British Geological Survey Technical Report, WA/89/26. |
| 1:50K maps on which the lithostratigraphical unit is found, and map code used: |
|
S033
S033
S034
S032
|
