| Computer Code: |
SBTI |
Preferred Map Code: |
SB |
| Status Code: |
Full |
| Age range: |
Devensian Stage (QD)
— Devensian Stage (QD) |
| Lithological Description: |
Reddish brown cobbly sandy clay diamicton, very compact, generally massive and matrix-supported, containing clasts mainly of Borrowdale Volcanic Group rocks (rhyolite, welded tuff, slate), granite and granophyre from the Lake District. Has tightly clustered clast fabric typical of a lodgement till. |
| Definition of Lower Boundary: |
Sharp, irregular, unconformable contact with bedrock. |
| Definition of Upper Boundary: |
Ground surface, or sharp, undulating, unconformable contact with overlying glaciolacustrine laminated silt and clay (Bark Butts Silt Member); glaciofluvial cobble gravel (Whin Garth Gravel Member); or by various Flandrian deposits such as peat and alluvium. |
| Thickness: |
To at least 6m |
| Geographical Limits: |
Western side of Lake District, inland of the limit of the "Gosforth Oscillation". |
| Parent Unit: |
Blengdale Glacigenic Formation (BLGL)
|
| Previous Name(s): |
Boulder clay of Lake District provenance [Obsolete Name and Code: Use SBTI]
(-1164)
|
| Alternative Name(s): |
none recorded or not applicable
|
| Stratotypes: |
| Type Section |
Waterfall section (NY00NE CA701) 120m downstream of Bleng Bridge, Blengdale, Lake District. Base of unit not exposed but very probably overlies bedrock. 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 |
| 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.] |
| 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. |
| Trotter, F M, Hollingworth, S E, Eastwood T and Rose, W C C. 1937. Gosforth District. Geological Survey Memoir, England and Wales, Sheet 37. |
| 1:50K maps on which the lithostratigraphical unit is found, and map code used: |
| none recorded or not applicable |
