The BGS Lexicon of Named Rock Units — Result Details

Elenid Till Member

Computer Code: ELTI Preferred Map Code: notEntered
Status Code: Full
Age range: Devensian Stage (QD) — Devensian Stage (QD)
Lithological Description: Generally stiff, blue-grey, stony, sandy and silty clay and clayey gravel, characteristically containing Lower Palaeozoic clasts (derived from the Cambrian Mountains). Subordinate stratified sand and gravel are locally present. Colour and dominant clast composition are variable and generally reflect the local bedrock geology. In the Gower it contains shell fragments (Bowen, 1999).
Definition of Lower Boundary: Generally unconformable on bedrock or regolith/head (e.g. Davies et al., 1997). At Broughton Bay it unconformably overlies Ipswichian raised beach deposits and head (Campbell and Bowen, 1989, p.52-54) of the Pennard Formation of Bowen (1999)
Definition of Upper Boundary: Generally the ground surface or contact with overlying Peat, Head (Severn and Avon Catchments and West Wales Catchments subgroups). Near Llanrhystud it is overlain by red sandy diamicton of the St Asaph Glacigenic Formation (see Campbell and Bowen, 1989; Davies et al., 1997)
Thickness: Highly variable, locally in excess of 30m
Geographical Limits: Mid and west Wales, southwest Wales approximately west of Swansea and including the Gower.
Parent Unit: Plynlimon Glacigenic Formation (PLYNT)
Previous Name(s): Elenid Formation (*933)
Central Wales Drift (-4636)
Alternative Name(s): none recorded or not applicable
Stratotypes:
Partial Type Section  Coastal section between Morfa Bychan and Mynachdy'r-graig in Cardigan Bay (Ceredigion) exposing up to 40 m of drift overlying, and blanketed against, a pre-Devensian 'fossil cliff'. A basal Head deposit is sharply overlain by up to 30 m of glacial deposits of the Elenid Till Member (Plynlimon Glacigenic Formation)exhibiting evidence of solifluction, itself sharply overlain and overstepped by Head and Loess. Campbell and Bowen, p.63-65 (1993); Davies et al. (1997) 
Reference(s):
Davies, J R, Fletcher, C J N, Waters, R A, Wilson, D, Woodhall, D G and Zalasiewicz, J A, 1997. Geology of the country around Llanilar and Rhayader. Memoir for 1:50 000 Geological Sheets 178 and 179. 
Campbell, S and Bowen, D Q. 1989. Quaternary of Wales. Geological Conservation Review. (Peterborough: Nature Conservancy Council.) 
Bowen, D Q, 1999. Wales. Chapter 7 in Bowen, D Q (Editor), A revised correlation of Quaternary deposits in the British Isles. Geological Society of London Special Report, No.23. 
Bowen, D Q. 2005. South Wales. In Lewis, C A and Richards, A E (editors), The glaciations of Wales and adjacent areas. (Logaston Press.) 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
none recorded or not applicable