The BGS Lexicon of Named Rock Units — Result Details

Ehen Alluvium Formation

Computer Code: EHEN Preferred Map Code: notEntered
Status Code: Full
Age range: Holocene Epoch (QH) — Holocene Epoch (QH)
Lithological Description: Sands, gravels silts and clays forming river terraces and underlying floodplains.
Definition of Lower Boundary: Sharply erosional, unconformable on all older Quaternary deposits (particularly till) and bedrock.
Definition of Upper Boundary: The ground surface, or overlain by peat of the Blelhem Peat Formation, or overlain by blown sand of the Drigg Point Sand Formation.
Thickness: Typically up to 12m thick in the type area.
Geographical Limits: 1:50k Sheets 37 Gosforth and 38 Whitehaven, western Cumbria and applied to all alluvial deposits within the west Cumbria area, between Whitehaven and Muncaster, of the Cumbria-Lancashire Catchments Subgroup area.
Parent Unit: Cumbria-Lancashire Catchments Subgroup (CLCA)
Previous Name(s): Alluvium And River Terrace Deposits (-2681)
Alluvial Fan Deposits (ALF)
Alternative Name(s): none recorded or not applicable
Stratotypes:
Type Area  Alluvium and river terraces within the valley of the River Ehen between Egremont and Sellafield, west Cumbria. Nirex Science Report SA/97/045 (Issue 2.0). 1997. 
Partial Type Section  Northern Bank of the River Ehen 200m south of Middlebank Farm, southsouthwest of Beckermet, west Cumbria. The Middlebank Silt Member of Nirex Science Report SA/97/045 (Issue 2.0). 1997. 
Partial Type Section  0.9-1.5m depth in Nirex borehole QBH9, 1km north of Starling Castle (west of Sellafield), west Cumbria. The Starling Gravel Member of Nirex Science Report SA/97/045 (Issue 2.0). 1997. 
Reference(s):
Trotter, F M, Hollingworth, S E, Eastwood T and Rose, W C C. 1937. Gosforth District. Geological Survey Memoir, England and Wales, Sheet 37. 
Merritt, J W and Auton, C A. 1997. Quaternary lithostratigraphy of the Sellafield district. Nirex Science Report SA/97/045 (Issue 2.0). [Report prepared for UK Nirex Ltd. 69pp, 5 tables, 20 figures, 14 enclosures and one appendix.] 
Auton, C A, Alexander, S A, Eaton, G P, McMillan, A A, Skinner, A C and Wealthall, G P. 1997. Logging and interpretation of Quaternary boreholes (QBH) drilled in the Sellafield area during 1966. Nirex Science Report SA/97/043 (Issue 2.0). 
Akhurst, M C, Chadwick, R A, Holliday, D W, McCormac, M, McMillan, A A, Millward, D, Young, B, Ambrose, K, Auton, C A, Barclay, W J, Barnes, R P, Beddoe-Stephens, B, James, J C W, Johnson, H, Jones, N S, Glover, B W, Hawkins, M P, Kimbell, G S, MacPherson, K A T, Merritt, J W, Milodowski, A E, Riley, N J, Robins, N S, Stone, P and Wingfield, R T R. 1997. The geology of the west Cumbria district. Memoir of the British Geological Survey, Sheets 28, 37 and 47 (England and Wales). 138pp. 
Eastwood T, and others. 1968. Geology of the country around Whitehaven. Memoir of the Geological Survey of Great Britain, Sheet 28 (England and Wales). 
Merritt, J W, Auton, C A, Browne, M A E, Neilson, G and McMillan, A A. 1995. Characterisation of the onshore Quaternary deposits around Sellafield, Cumbria, Phase II. Nirex Science Report 768. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
none recorded or not applicable