The BGS Lexicon of Named Rock Units — Result Details

Gretna Till Formation

Computer Code: GRET Preferred Map Code: G
Status Code: Full
Age range: Devensian Stage (QD) — Devensian Stage (QD)
Lithological Description: Reddish brown, sandy, silty, clayey diamicton with clasts of greywacke, red sandstone, siltstone and grey granodiorite. Uppermost 3m generally quite variable in lithology and compactness, with lenses of sand, gravel, silt and clay. Commonly becoming more compact and stony with depth.
Definition of Lower Boundary: Unconformable on bedrock.
Definition of Upper Boundary: At surface or overlain conformably by glaciofluvial / glaciolacustrine or Flandrian sediments.
Thickness: 20m
Geographical Limits: Solway Lowlands.
Parent Unit: Irish Sea Coast Glacigenic Subgroup (ISCG)
Previous Name(s): Boulder clay [Obsolete Name and Code: Use TILL] (BOC)
Boulder clay [Obsolete Name and Code: Use TILL] (BOC)
Alternative Name(s): none recorded or not applicable
Stratotypes:
Partial Type Section  River cliff of the Logan Burn, 1.5km south of Chapelknowe, Dumfries-shire. Geologists' field locality card ME300 
Partial Type Section  Section behind cowshed at Plumpe Farm, 1km east of Gretna, Dumfries-shire Geologists' Field Locality ME 262 - 263 
Reference(s):
Trotter, F M, 1922. Report from the Cumberland District. In: Summary of the Progress of the Geological Survey of Great Britain for 1921, 46-48. 
Trotter, F M and Hollingworth, S E, 1932. The glacial sequence in the North of England. Geological Magazine, Vol.69, 374-380. 
McMillan, A A, Merritt, J W, Auton, C A and Golledge, N R [In preparation]. The Quaternary geology of the Solway area. BGS Research Report. 
Trotter, F M. 1929. The glaciation of the Eastern Edenside, the Alston Block, and the Carlisle Plain. Quarterly Journal of the Geological Society of London, Vol.85, 549-612. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
E011 E017 S010 S010 S011 S006