Computer Code: |
ARDS |
Preferred Map Code: |
ARS |
Status Code: |
Full |
Age range: |
Devensian Stage (QD)
— Devensian Stage (QD) |
Lithological Description: |
Rhythmically-bedded sequence of silty clays, silts and silty sands, typically graded. Subordinate diamicton and gravel. Origin thought to be glaciomarine. |
Definition of Lower Boundary: |
Unseen; on lodgement till or bedrock. |
Definition of Upper Boundary: |
Gradational contact with Alturlie Gravels Formation above, or unconformable boundary with younger deposits. |
Thickness: |
At least 20m |
Geographical Limits: |
Southern shores of the inner Moray Firth, between Inverness and Elgin. |
Parent Unit: |
Banffshire Coast and Caithness Glacigenic Subgroup (BCD)
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Previous Name(s): |
none recorded or not applicable
|
Alternative Name(s): |
none recorded or not applicable
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Stratotypes: |
Partial Type Section |
"Kirkton Pit". Old clay pit (re-excavated Sept 1990) in Main Lateglacial Cliffline (trimmed in Mid-Holocene times). |
Partial Type Section |
"Contorted silts of Ardersier". Cliff section in Main Lateglacial Cliffline (trimmed in Mid-Holocene times). See Firth, 1989. |
Reference(s): |
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. |
Fletcher, T P et al. 1996. Geology of the Fortrose and eastern Inverness district. Memoir of the British Geological Survey, Sheet 84W (Scotland). |
Firth, C R. 1989. A reappraisal of the supposed Ardersier Readvance, inner Moray Firth. Scottish Journal of Geology, Vol 25, 249-261. |
1:50K maps on which the lithostratigraphical unit is found, and map code used: |
S084
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