| Computer Code: |
ANST |
Preferred Map Code: |
AS |
| Status Code: |
Full |
| Age range: |
Tonian Period (AT)
— Tonian Period (AT) |
| Lithological Description: |
Striped association of semipelite, psammite and siliceous psammite with subordinate quartzite and calc-silicate rock, variably gneissose. |
| Definition of Lower Boundary: |
Conformably upon Creag an Loin Psammite Formation (CRAN); marked by incoming of distinctive garnetiferous quartzite and/or semipelite. |
| Definition of Upper Boundary: |
Overlain by Creag Liath Psammite Formation (CGLH); typically marked by a narrow shear zone. Elsewhere overlain by Grampian Shear Zone. |
| Thickness: |
600-700 metres. |
| Geographical Limits: |
Central Highlands of Scotland. Newtonmore - Glen Banchor - Kincraig areas. |
| Parent Unit: |
Glen Banchor Subgroup (GLBA)
|
| Previous Name(s): |
none recorded or not applicable
|
| Alternative Name(s): |
none recorded or not applicable
|
| Stratotypes: |
| Type Area |
An Stac [NH 680 004], north of Glen Banchor. |
| Reference Section |
Immediately north of Creag an Loin [NH 6875 0164]. |
| Reference(s): |
| Krabbendam, M. 2021. A stratigraphic framework for the early Neoproterozoic successions of the Northern Highlands of Scotland. UK Stratigraphic Framework Series. British Geological Survey Open Report, OR/21/072. 86pp. |
| Leslie, A G, Robertson, S, Smith, M, Banks, C J, Mendum, J R, and Stephenson, D. 2013. The Dalradian rocks of the northern Grampian Highlands of Scotland. Proceedings of the Geologists' Association, Vol. 124, 263-317. |
| 1:50K maps on which the lithostratigraphical unit is found, and map code used: |
|
S063
S064
S074
|
