The BGS Lexicon of Named Rock Units — Result Details

Plump Bridge Till Member

Computer Code: PLBT Preferred Map Code: PBT
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.
Definition of Lower Boundary: Commonly a gradational, glacitectonic contact with underlying Plumpe Farm Sand and Gravel Formation [or members thereof], or Chapelknowe Till Member. Otherwise unconformable on bedrock.
Definition of Upper Boundary: At surface or overlain conformably by glaciofluvial/glaciolacustrine or Flandrian sediments.
Thickness: 10m
Geographical Limits: Solway Lowlands.
Parent Unit: Gretna Till Formation (GRET)
Previous Name(s): Upper Boulder Clay [Obsolete Name and Code: Use FWTI, GOGL, HMTI, PKSA, PLBT, RSTI, STPTG] (-4662)
Alternative Name(s): none recorded or not applicable
Stratotypes:
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. 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. 
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, 1923. Report from the Cumberland District. In: Summary of Progress of the Geological Survey of Great Britain for 1922, 61-63. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
E011 S006