Computer Code: |
GRCA |
Preferred Map Code: |
GRC |
Status Code: |
Full |
Age range: |
Devensian Stage (QD)
— Holocene Epoch (QH) |
Lithological Description: |
The Grampian Catchments Subgroup encompasses the mainly late-Devensian and Holocene alluvial and river terrace deposits that occur in the Grampian Highlands.
Sand, gravel, clay and organic deposits. Sand, gravel and boulders include clasts derived from rocks cropping out in the eastern Grampian Mountains and Buchan.
Alluvium and river terrace deposits, and associated organic and lacustrine deposits.
Devensian to Holocene (MIS 2 - 1). |
Definition of Lower Boundary: |
Unconformable contact with units of the Central Grampian, East Grampian, Inverness, Banffshire Coast and Caithness, and Logie-Buchan Glacigenic subgroups, and with bedrock. |
Definition of Upper Boundary: |
Generally the ground surface, but units of this subgroup locally interfinger with units of the British Coastal Deposits Group. |
Thickness: |
Up to 25 m. |
Geographical Limits: |
The Eastern Grampian Highlands and Buchan. |
Parent Unit: |
Britannia Catchments Group (BCAT)
|
Previous Name(s): |
none recorded or not applicable
|
Alternative Name(s): |
none recorded or not applicable
|
Stratotypes: |
Type Area |
The Eastern Grampian Highlands and Aberdeenshire and Moray Firth lowlands. See also the stratotypes of constituent formations. |
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. |
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 |