Computer Code: |
SHETG |
Preferred Map Code: |
SHET |
Status Code: |
Full |
Age range: |
Devensian Stage (QD)
— Devensian Stage (QD) |
Lithological Description: |
A suite of glacial, glaciofluvial and glaciolacustrine deposits that contain clasts derived predominantly from rocks cropping out on the Shetland archipelago, including sandy diamictons (till), sand, gravel, silt and clay. Deposited by ice that radiated outwards from an ice divide positioned along the axis of the archipelago. |
Definition of Lower Boundary: |
Sharp, unconformable contact with bedrock or with units of the Shetland (Albion) Glacigenic Subgroup. |
Definition of Upper Boundary: |
Ground surface or unconformable contact with various Flandrian deposits, predominantly peat. |
Thickness: |
To 20m |
Geographical Limits: |
The Shetland archipelago, Foula and Fair Isle. |
Parent Unit: |
Caledonia Glacigenic Group (CALI)
|
Previous Name(s): |
none recorded or not applicable
|
Alternative Name(s): |
none recorded or not applicable
|
Stratotypes: |
Type Area |
The Shetland archipelago, Foula and Fair Isle. Bowen 1999. See also the srtatotypes of constituent informal formations documented in Bowen (1999). |
Reference(s): |
Bowen, D Q. 1999. A revised correlation of Quaternary deposits in the British Isles. Geological Society Special Report, No. 23. |
McMillan, A A, Hamblin, R J O, and Merritt, J W. 2005. An overview of the lithostratigraphical framework for the Quarternary and Neogene deposits of Great Britain (onshore). British Geological Survey Research Report RR/04/04. |
1:50K maps on which the lithostratigraphical unit is found, and map code used: |
none recorded or not applicable |