Computer Code: |
RVTI |
Preferred Map Code: |
RVT |
Status Code: |
Full |
Age range: |
Devensian Stage (QD)
— Devensian Stage (QD) |
Lithological Description: |
Moderate brown sandy silty gravelly diamicton, very compact, matrix-supported, generally massive, containing moderately well dispersed, subangular to subrounded clasts of granophyre, granite, Borrowdale Volcanic Group rocks (rhyolite, welded tuff, slate), with some red sandstone, ironstone and shell fragments. |
Definition of Lower Boundary: |
Not seen in sections, but probably mainly a sharp, irregular, unconformable contact with bedrock. Locally a sharp, unconformable contact with a sequence of reddish or yellowish brown sand, silt and clay of the Barn Scar Sand and Silt Member of the Seascale Glacigenic Formation. |
Definition of Upper Boundary: |
Sharp, undulating, unconformable contact with overlying sand and gravel deposits or till units of the Gosforth Glacigenic Formation. |
Thickness: |
To 10m |
Geographical Limits: |
The coast to the west of the Lake District inland of the limit of the "Gosforth Oscillation" between Cleator and Ravenglass. |
Parent Unit: |
Seascale Glacigenic Formation (SEAG)
|
Previous Name(s): |
Lower Boulder Clay [Obsolete Name and Code: Use CHAK, STIL, SEAG, RVTI, LWTI, STPTG]
(-2079)
|
Alternative Name(s): |
none recorded or not applicable
|
Stratotypes: |
Type Section |
Sea cliff section 500m south of Ravenglass, Cumbria. Merritt and Auton, 2000. |
Reference Section |
BNFL Drigg Off-site Borehole C, between 16 and 18m depth. 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. |
Huddart, D. 1991. The glacial history and glacial deposits of the north and west Cumbrian lowlands, 151-167 in Ehlers, J, Gibbard, P L and Rose, J (editors), Glacial deposits in Great Britain and Ireland. [London: Balkema.] |
Eastwood T, and others. 1968. Geology of the country around Whitehaven. Memoir of the Geological Survey of Great Britain, Sheet 28 (England and Wales). |
1:50K maps on which the lithostratigraphical unit is found, and map code used: |
none recorded or not applicable |