Computer Code: |
CGLH |
Preferred Map Code: |
LI |
Status Code: |
Full |
Age range: |
Tonian Period (AT)
— Tonian Period (AT) |
Lithological Description: |
Interbanded gneissose psammite, siliceous psammite with subordinate micaceous psammite and semipelite. Distinctive porphyroclasts of K-feldspar common. |
Definition of Lower Boundary: |
Conformable (if sheared) upon An Stac Semipelite and Psammite Formation (ANST); marked by incoming of psammite. |
Definition of Upper Boundary: |
Unconformably overlain by Grampian and Appin Group rocks (Dalradian Supergroup - DALN). |
Thickness: |
c. 400 m (maximum; estimated; deformed). |
Geographical Limits: |
Central Highlands of Scotland. Glen Banchor - Kincraig area. |
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 |
Creag Liath, north of Glen Banchor [NH664 007]. |
Reference Section |
Creag na H'iolare - basal contacts and lower parts. |
Reference Section |
Unnamed burn 300 m west of Gergask Crag. |
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. |
Robertson, S, and Smith, M. 1999. The significance of the Geal Charn-Ossian steep belt in basin development in the central Scottish Highlands. Journal of the Geological Society, Vol. 156, 1175-1182. |
1:50K maps on which the lithostratigraphical unit is found, and map code used: |
none recorded or not applicable |