The BGS Lexicon of Named Rock Units — Result Details

Carse Clay Formation

Computer Code: CARCL Preferred Map Code: notEntered
Status Code: Full
Age range: Devensian Stage (QD) — Holocene Epoch (QH)
Lithological Description: Clayey silt and clay, commonly rooty and structureless; also highly laminated with silt and very fine- to medium-, locally coarse-grained sand with pebbles up to 5mm and fragments of vivianite; grey and brownish grey, finely micaceous, dark sulphidic patches. In sand dominated successions in outer estuary situations, coarse gravel also occurs at the base of the local member. Fuller descriptions of lithology in the entries for members: the Gowrie Silt, Carse of Gowrie Clay, Carey Silt and Kingston Sand members in the Tay-Earn area and the Letham Silt, Carse of Stirling Clay, Claret Clay and Grangemouth Silt members in the Forth area.
Definition of Lower Boundary: Unconformable on the sub-Carse Peat (Flanders Moss Peat Formation); unconformable on the Forth Clay and Errol Clay formations and older deposits including the Wilderness Till Formation and bedrock.
Definition of Upper Boundary: Upper boundary unconformable with modern alluvium, and commonly at the surface.
Thickness: Veneer to more than 27m
Geographical Limits: Lower Tay valley from northwest of Perth, Tay estuary and Firth of Tay; lower Earn valley east of Forteviot, and estuary (Carse of Gowrie); lower Eden valley east of Cupar and estuary; Montrose Basin area. Forth valley from Aberfoyle eastwards (Carse of Stirling), Forth estuary.
Parent Unit: British Coastal Deposits Group (COAS)
Previous Name(s): Carse clay (Undivided) [Obsolete Name and Code: Use CARCL] (-2661)
Alternative Name(s): none recorded or not applicable
Stratotypes:
Partial Type Section  Culfargie Borehole, BGS Ref NO11NE/2, from surface to 7.34m depth, lower Earn estuary. 
Reference Section  Burnside Borehole, BGS Ref NO32NW/11, from surface to 7.97m depth, lower Tay estuary. 
Reference(s):
Paterson, I B. 1981. The Quaternary geology of the Budden Ness area of Tayside, Scotland. Report of the Institute of Geological Sciences, No.81/1. 
Browne, M A E, Graham, D K and Gregory, D M 1984. Quaternary estuarine deposits in the Grangemouth area, Scotland. Report of the Institute of Geological Sciences, No.16/3. 
Paterson, I B, Armstrong, M and Browne, M A E. 1981. Quaternary estuarine deposits in the Tay-Earn area, Scotland. Report of the Institute of Geological Sciences, No.81/7. 
Francis, E H, Forsyth, I H, Read, W A and Armstrong, M. 1970. The geology of the Stirling district. Memoir of the Geological Survey of Great Britain, Sheet 39 (Scotland). 
Armstrong, M, Paterson, I B and Browne, M A E, 1985. Geology of the Perth and Dundee district. Memoir of the British Geological Survey, Sheets 48W, 48E and 49 (Scotland). 108pp. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
S031 S048 S048 S049 S057 S038 S039 S039 S040