The BGS Lexicon of Named Rock Units — Result Details

West Leys Sand And Gravel Formation

Computer Code: WLSG Preferred Map Code: notEntered
Status Code: Full
Age range: Wolstonian Stage (QO) — Wolstonian Stage (QO)
Lithological Description: Sandy gravel and gravelly sand, very pale brown to pale brown pebble to cobble grade, clast-supported with quartzose medium to coarse sand matrix; locally sand with dispersed pebbles. Clast angularity is variable from subangular to rounded. Clast lithologies are dominated by psammitic and quartzite metasedimentary rock, with subsidiary felsite, mafic igneous rocks, pelites, red and grey granites and red sandstone. The sediments display tabular cross beds showing palaeocurrent from the northwest, and crude horizontal bedding. Interpreted as either a proglacial or subglacial glaciofluvial sediment.
Definition of Lower Boundary: The lower boundary of this unit is a sharp erosional unconformity on angular gravel of the Camphill Gelifluctate Bed. It represents a discontinuous channel, (up to 1m in depth) eroded into the underlying deposit.
Definition of Upper Boundary: The upper boundary of the unit is unconformable - a subhorizontal, planar, erosion surface at the base of the yellowish brown diamicton of the Rottenhill Till Formation.
Thickness: To 1m
Geographical Limits: Buchan, northeast Scotland. The formation is currently only shown from Leys Quarry (disused) (centred on NK 0040 5250) on 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): Sand And Gravel (-4265)
Alternative Name(s): none recorded or not applicable
Stratotypes:
Type Section  Northeast face of Leys quarry (disused), 6.5km southeast of Stricken, Buchan, northeast Scotland. Hall and Jarvis, 1993. 
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.) 
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.) 
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.) 
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) 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
none recorded or not applicable