The BGS Lexicon of Named Rock Units — Result Details

Inverness (Albion) Glacigenic Subgroup

Computer Code: IAG Preferred Map Code: IVA
Status Code: Full
Age range: Mid Pleistocene (QPM) — Mid Pleistocene (QPM)
Lithological Description: Sandy diamictons (till), sand, gravel, silt and clay. Clasts are derived predominantly from the comminution of Devonian (Old Red Sandstone) sandstone, siltstone and conglomerate. Suite of glacial, glaciofluvial, glaciolacustrine and glaciomarine deposits. Mid-Pleistocene (MIS 13 - 6).
Definition of Lower Boundary: Sharp, unconformable, uneven contact with bedrock.
Definition of Upper Boundary: Ground surface or unconformably overlain by various units of the Inverness Glacigenic Subgroup or other subgroups.
Thickness: Up to 10 m.
Geographical Limits: The hinterland of the Moray Firth, including the north-eastern end of the Great Glen, the southern shores of the Moray Firth as far east as Buckie, the Black Isle and the land surrounding the Cromarty and Dornoch firths.
Parent Unit: Albion Glacigenic Group (ALBI)
Previous Name(s): Central Grampian Drift Group [Obsolete Name and Code: Use IAG] (-772)
Alternative Name(s): none recorded or not applicable
Stratotypes:
Type Area  See also the stratotypes of constituent formations, including the Cassie Till, Drummore Gravel, Craig an Daimh Gravel and Suidheig Till. 
Reference(s):
McMillan, A A, Hamblin, R J O, and Merritt, J W. 2011. A lithostratigraphical framework for onshore Quaternary and Neogene (Tertiary) superficial deposits of Great Britain and the Isle of Man. British Geological Survey Research Report, RR/10/03. 343pp. 
Stoker, M S, McMillan, A A and Waters, C N. Quaternary Stratigraphical Chart: Northern Britain. British Geological Survey, 1 poster. 
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