Computer Code: |
TBE |
Preferred Map Code: |
notEntered |
Status Code: |
Full |
Age range: |
Tonian Period (AT)
— Tonian Period (AT) |
Lithological Description: |
Conglomerate at base; green-grey sandstone with epidote, cross-bedded; increasing siltstone towards top of formation. |
Definition of Lower Boundary: |
Unconformable upon Lewisian Gneiss (L) (sheared and overturned). |
Definition of Upper Boundary: |
Conformably overlain by Loch na Dal formation (TBLN). Incoming of interbedded sandstone-mudstone. |
Thickness: |
Variable, maximum c. 270 m. |
Geographical Limits: |
Northwest Scotland: Isle of Skye: Sleat. |
Parent Unit: |
Sleat Group (TB)
|
Previous Name(s): |
Epidotic Grit Formation
(-561)
|
Alternative Name(s): |
none recorded or not applicable
|
Stratotypes: |
Type Section |
Coastal section at Rubha Guail, Sleat, Skye [NG 722 150 - NG 728 159]. |
Reference(s): |
Stewart, A D. 2002. The later Proterozoic Torridonian rocks of Scotland: their sedimentology, geochemistry and origin. Geological Society Memoir. Vol. 24. (The Geological Society.) |
Krabbendam, M, Bonsor, H, Horstwood, M S, and Rivers, T. 2017. Tracking the evolution of the Grenvillian foreland basin: Constraints from sedimentology and detrital zircon and rutile in the Sleat and Torridon groups, Scotland. Precambrian Research, Vol. 295, 67-89. |
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. |
Johnston, G S and Mykura, W. 1989. British regional geology: the Northern Highlands (4th edition) (London: HMSO for the British Geological Survey.) |
1:50K maps on which the lithostratigraphical unit is found, and map code used: |
S071
S061
|