The BGS Lexicon of Named Rock Units — Result Details

St Bees Sand And Gravel Member

Computer Code: SBSG Preferred Map Code: SBG
Status Code: Full
Age range: Devensian Stage (QD) — Devensian Stage (QD)
Lithological Description: Sand and gravel, coarsening upwards from pebbly sand to boulder gravel, dense, composed of angular to subrounded clasts of red (Permian) sandstone, white and yellow (Carboniferous) sandstone and ganister, black (Carboniferous) mudstone and coal, with some Borrowdale Volcanic Group rocks (rhyolite, welded tuff), greywacke sandstone and siltstone, limestone and grey (Criffel) granite. Top of unit commonly cemented by calcite. Palaeocurrents directed between NW and SW.
Definition of Lower Boundary: Gradational, conformable contact with laminated fine-grained sand, silt and clay of the St Bees Silt Member.
Definition of Upper Boundary: Sharp, undulating, unconformable contact with grey sandy pebbly silt diamicton of the St Bees Till Member of the Gosforth Glacigenic Formation.
Thickness: To 10m
Geographical Limits: Cumbrian coast between St Bees and Sellafield seaward of the limit of the "Gosforth Oscillation" between Cleator and Ravenglass.
Parent Unit: Seascale Glacigenic Formation (SEAG)
Previous Name(s): St Bees Sand and Gravel [Obsolete Name and Code: Use SBSG] (-3020)
Alternative Name(s): none recorded or not applicable
Stratotypes:
Type Section  Sea cliff section NX91SEME11, 220 to 290m south of the southernmost groyne on St Bees Beach, Cumbria. Nirex, 1997. 
Reference(s):
Merrit, J W and Auton, C A. 2000. An outline of the lithostratigraphy and depositional history of Quaternary deposits in the Sellafield district, west Cumbria. Proceedings of the Yorkshire Geological Society, Vol.53, 129-154 
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 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.] 
Huddart, D and Tooley, M J. 1972. The Cumberland Lowland field trip handbook. [Cambridge: Quaternary Research Association.] 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
none recorded or not applicable