The BGS Lexicon of Named Rock Units — Result Details

York Moraine Member

Computer Code: YORKM Preferred Map Code: notEntered
Status Code: Full
Age range: Devensian Stage (QD) — Devensian Stage (QD)
Lithological Description: Glacial till comprising sandy clay, clayey sand and clay with erratic pebbles, cobbles and boulders mainly of Carboniferous sandstone and limestone. The Member also includes local deposits of sand and gravel plus local deposits of clay and laminated clay incorporated into the sequence.
Definition of Lower Boundary: Unconformable on bedrock, or pre-existing superficial deposits such as fluvial and glacial deposits.
Definition of Upper Boundary: The present land surface, which forms an elongated moraine ridge, or unconformable contact with overlying deposits to north and south including the Alne Glaciolacustrine Formation and the Elvington Glaciolacustrine Formation respectively.
Thickness: To 50m
Geographical Limits: Yorkshire in the vicinity of York. The moraine ridge exists from just east of Bicketon [445197, 450188] in the west through York to Sand Hutton [471257, 459893].
Parent Unit: Vale Of York Formation (VYORK)
Previous Name(s): York Moraine (-4989)
Alternative Name(s): none recorded or not applicable
Stratotypes:
Type Area  Part of morainic ridge between Askham Bog in the west and Copmanthorpe in the south extending from [SE 425 720] to [SE785 806]. 
Reference(s):
Kendall, P F and Wroot, H E. 1924. The geology of Yorkshire: An illustration of the evolution of northern England, p.528. Printed privately for the authors in Vienna by Hollinek Brothers, printers of scientific books. 
Cooper, A H and Burgess, I C. 1993. Geology of the country around Harrogate. Memoir for 1:50000 geological sheet 62 (England and Wales). London: HMSO for the British Geological Survey. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
E062 E063 E070 E071