| 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)
|
| Previous Name(s): |
none recorded or not applicable
|
| Alternative Name(s): |
none recorded or not applicable
|
| 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): |
| 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. |
| 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
|
