| Computer Code: |
SRGA |
Preferred Map Code: |
SG |
| Status Code: |
Full |
| Age range: |
Neoproterozoic Era (AZ)
— Neoproterozoic Era (AZ) |
| Lithological Description: |
Gneissose semipelite with local gradations towards micaceous psammite. Typically magnetite-rich and hence notably magnetic. Thin amphibolites occur locally throughout. |
| Definition of Lower Boundary: |
Lower boundary not exposed. Probably tectonic boundary with Grampian Group rocks. |
| Definition of Upper Boundary: |
Where magnetite semipelite is succeeded (rapid / sharp transition) by tremolite schist of the Iubhair Beag Calcareous Formation. |
| Thickness: |
0 - c. 400m. |
| Geographical Limits: |
Eastern part of Ardverikie Forest between the Allt Cam [NN 50 78] and the Allt Mhainisteir [NN 542 860]. On sheet 63E [Dalwhinnie]. |
| Parent Unit: |
Lochaber Subgroup (DALO)
|
| Previous Name(s): |
none recorded or not applicable
|
| Alternative Name(s): |
none recorded or not applicable
|
| Stratotypes: |
| Type Area |
Northern shoulder of Sron Garbh, Coire Cheap. |
| Reference(s): |
| Robertson, S and Mendum, J R, in press. Lithostratigraphy of the Grampian and Appin Groups in the Dalwhinnie district, sheet 63E, Scotland. British Geological Survey Technical Report. |
| 1:50K maps on which the lithostratigraphical unit is found, and map code used: |
|
S063
|
