The BGS Lexicon of Named Rock Units — Result Details

Leys Till Formation

Computer Code: LEYST Preferred Map Code: notEntered
Status Code: Full
Age range: Anglian Stage (QA) — Wolstonian Stage (QO)
Lithological Description: Non-calcareous, matrix supported, gravelly, slightly clayey, silty sand diamicton. Dominantly pale olive-brown and olive-brown (upper interval shows extensive yellowish brown and strong brown mottling). Non-calcareous, matrix supported, gravelly, slightly clayey silty sand. Clast types include quartzites, psammitic and pelitic metasedimentary rocks, felsite, mafic igneous rocks and grey granite. The lower intervals contain lenses and small rafts of kaolinised metasedimentary rocks and grussified mafic igneous rocks. Interpreted as a subglacial till.
Definition of Lower Boundary: As seen in geological test pits either sharply unconformable, planar, boundary on weathered bedrock or gradational glaciotectonised, boundary (over c.0.4m) showing incorporation of lenses and small rafts of weathered metasedimentary or mafic igneous rock types.
Definition of Upper Boundary: As seen in geological test pits sharp, planar, erosive upper boundary with overlying felsite-rich gravels of the Denend Gravel Formation.
Thickness: To 2.5m
Geographical Limits: Buchan, northeast Scotland. This formation is currently only known from within the confines of Leys Quarry (disused) (centred on NK 0040 5250). Sheet 87W (Ellon). The unit might be regionally significant and present locally across northeast Scotland.
Parent Unit: East Grampian (Albion) Glacigenic Subgroup (EGAG)
Previous Name(s): Leys Till Formation (LEYST)
Leys Till [Obsolete Name and Code: Use LEYST] (-1652)
Leys Member [Obsolete Name and Code: Use LEYST] (-4757)
Leys Till Formation (LEYST)
Alternative Name(s): none recorded or not applicable
Stratotypes:
Partial Type Section  BGS-registered geological test pit NK05 SW/47. 1.6-3.6m depth. Pit excavated in the floor of Leys Quarry (disused), 6.5km southeast of Stricken, Buchan, northeast Scotland, May 1987. Top of unit is seen in pit. Note grid reference (NK 0037 5230) of pit might be in error as it falls outwith the area of the quarry as it was in 1987. Hall, Jarvis and Duck, 1989. 
Partial Type Section  BGS-registered geological pit NK05 SW/44. 1-3.5m depth. Pit excavated in the floor of Leys quarry (disused), 6.5km southeast of Stricken, Buchan, northeast Scotland, May 1987. Base of unit seen in pit. Note: grid reference (NK 0047 5234) might be in error as it falls outwith the area of the quarry as it was in 1987. Hall, Jarvis and Duck. 1989. 
Reference(s):
Connell, E R and Hall, A M. 2000. Kirkhill and Leys quarries. 65-67 in Merritt, J W, Connell, E R and Bridgland, D R (editors), The Quaternary of the Banffshire Coast and Buchan: Field Guide. (London: Quaternary Research Association.) 
Hall, A M, Jarvis, J and Duck, R. 1989. Survey of Quaternary deposits adjacent to Kirkhill Quarry. CSD Report 924, (Peterborough: Nature Conservancy Council.) 75pp. 
Sutherland, D G. 1999. Scotland. 99-114 in Bowen D Q (Editor), A revised correlation of Quaternary deposits in the British Isles. Special Report of The Geological Society of London, No.23. 
Merritt, J W, Connell, E R and Bridgland, D R (editors). 2000. The Quaternary of the Banffshire Coast and Buchan; Field Guide. (London: Quaternary Research Association.) 
Merritt, J W, Auton, C A, Connell, E R, Hall, A M and Peacock, J D. 2003. The Cainozoic geology and landscape evolution of north-east Scotland. Memoir of the British Geological Survey, Sheets 66E, 67, 76E, 77, 86E, 87W, 87E, 95, 96W, 96E and 97 (Scotland) 
Hall, A M and Jarvis, J. 1993. Kirkhill. 225-230 in Gordon, J E and Sutherland, D G (editors), Quaternary of Scotland. Geological Conservation Review Series: 6. (London: Chapman and Hall.) 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
none recorded or not applicable