The BGS Lexicon of Named Rock Units — Result Details

St Bees Till Member

Computer Code: STBT Preferred Map Code: notEntered
Status Code: Full
Age range: Devensian Stage (QD) — Devensian Stage (QD)
Lithological Description: Pebbly silty clay diamicton, calcareous, very still, massive, matrix-supported; dark greyish brown. It contains well dispersed subangular to rounded pebbles of red sandstone, white and yellow Coal Measure sandstones, coal, greywacke, slate, limestone and Borrowdale Volcanic Group rocks. It is typically thinly interlaminated with dark yellowish orange silt towards its base; locally a dense, thickly interlaminated bed (<3m thick) of fine-grained sand and silt (showing ripple-drift lamination) occurs at the base of the Member.
Definition of Lower Boundary: Generally conformable contact (but with evidence of glacitectonic shearing) on the St Bees Sand and Gravel Member of the Seascale Glacigenic Formation.
Definition of Upper Boundary: Gradational contact with the base of the overlying Gutterfoot Sand Member of the Gosforth Glacigenic Formation.
Thickness: 3.0m thick at its Type Section, 2.0m thick at its Reference Section.
Geographical Limits: Part of the St Bees Moraine on 50k Sheet 28 (Whitehaven).
Parent Unit: Gosforth Glacigenic Formation (GOGL)
Previous Name(s): St Bees Till (-3430)
Alternative Name(s): none recorded or not applicable
Stratotypes:
Type Section  Sea cliff sections 400-500m northwest of footbridge at Seamill end of St Bees Beach, c.750m southsoutheast of St Bees Railway Station, west Cumbria. Nirex Science Report SA/97/045 (Issue 2.0) 1997. 
Reference Section  Sea cliff at northern end of St Bees Beach (Log NX91SE ME14 of Nirex Science Report 768. 1995), c.100m west of the IRB station at St Bees, west Cumbria 
Reference(s):
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.] 
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. 
Huddart, D and Tooley, M J. 1972. The Cumberland Lowland field trip handbook. [Cambridge: Quaternary Research Association.] 
Auton, C A and Merritt, J W. 2004. Geological summary report: A review of onshore evidence of Lateglacial and Holocene sea level change in the St Bees-Sellafield area. British Geological Survey Report EE03_0870 for Halcrow H and S Limited. 49pp. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
none recorded or not applicable