Computer Code: |
ALGR |
Preferred Map Code: |
SYMB |
Status Code: |
Full |
Age range: |
Devensian Stage (QD)
— Devensian Stage (QD) |
Lithological Description: |
Sand and gravel, typically a deltaic coarsening-upwards sequence. Origin thought to be glaciomarine. |
Definition of Lower Boundary: |
Gradational, from the Ardersier Silts Formation below, or unconformable, with lodgement till or bedrock below. |
Definition of Upper Boundary: |
Unconformable with Late Devensian raised marine deposits above, or the present ground surface. |
Thickness: |
At least 20m |
Geographical Limits: |
The area surrounding the southern shore of the inner Moray Firth, between Inverness and Elgin. |
Parent Unit: |
Banffshire Coast and Caithness Glacigenic Subgroup (BCD)
|
Previous Name(s): |
Glacial sand and gravel [Obsolete Name and Code]
(GSG)
|
Alternative Name(s): |
none recorded or not applicable
|
Stratotypes: |
Partial Type Section |
Mid Coul Gravel Pit, Tornagrain, 12km east-north-east of Inverness. |
Partial Type Section |
Bothyhill Gravel Pit, Alturlie Point. See Merritt, 1990. |
Reference(s): |
Merritt, J W, 1990. New evidence for ?glaciomarine deltaic deposits at Alturie Gravel Pit. 102-105 in Auton, C A, Firth, C R and Merritt, J W. Beauly to Nairn: Field Guide. Quaternary Research Association, Cambridge. |
Fletcher, T P et al. 1996. Geology of the Fortrose and eastern Inverness district. Memoir of the British Geological Survey, Sheet 84W (Scotland). |
Merrit, J W, Auton, C A, and Firth. C R. 1995. Ice-proximal glaciomarine sedimentation and sea-level change in the Inverness area, Scotland: A review of the deglaciation of a major ice stream of the British Late Devensian ice sheet. Quaternary Science Reviews, Vol.14, 289-329. |
1:50K maps on which the lithostratigraphical unit is found, and map code used: |
S084
|