The BGS Lexicon of Named Rock Units — Result Details

Western Isles (Albion) Glacigenic Subgroup [Name Reserved For Possible Future Use]

Computer Code: WIAG Preferred Map Code: WIA
Status Code: Pending Upgrade
Age range: Cromerian Stage (QC) — Wolstonian Stage (QO)
Lithological Description: A suite of glacial, glaciofluvial and glaciolacustrine deposits that contain clasts derived predominantly from Lewisian rocks of the Western Isles, including sandy diamictons (till), sand, gravel, silt and clay. Deposited by ice that mainly radiated outwards from an ice divide positioned along the western seaboard of the Western Isles archipelago.
Definition of Lower Boundary: Sharp, unconformable contact with bedrock.
Definition of Upper Boundary: Planar unconformable contact with units of the Western Isles Glacigenic Subgroup.
Thickness: To 5m
Geographical Limits: The Western Isles archipelago.
Parent Unit: Albion Glacigenic Group (ALBI)
Previous Name(s): none recorded or not applicable
Alternative Name(s): none recorded or not applicable
Type Area  The Western Isles archipelago. See also the stratotypes of constituent informal formations documented in Bowen (1999). 
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. 
Bowen, D Q. 1999. A revised correlation of Quaternary deposits in the British Isles. Geological Society Special Report, No. 23. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
none recorded or not applicable