| Computer Code: |
UWIS |
Preferred Map Code: |
notEntered |
| Status Code: |
Full |
| Age range: |
Devensian Stage (QD)
— Holocene Epoch (QH) |
| Lithological Description: |
Glaciomarine/marine clay and silt with local concentrations of sand. Seismically well-ordered character, exhibiting drape, onlap and progradation features. |
| Definition of Lower Boundary: |
Disconformity at top of underlying Cardigan Bay Formation or incised into pre-Quaternary rockhead surface. |
| Definition of Upper Boundary: |
Unconformity at base of overlying Surface Sands Formation (the "Y" seismic unconformity surface of Akhurst et al,1997). Locally crops out at sea bed. |
| Thickness: |
10 to 20m, locally thickening to 60m in channel infills. |
| Geographical Limits: |
Irish Sea. |
| Parent Unit: |
British Coastal Deposits Group (COAS)
|
| Previous Name(s): |
none recorded or not applicable
|
| Alternative Name(s): |
none recorded or not applicable
|
| Stratotypes: |
| Reference Section |
Offshore BGS borehole No. 71/62 at 7 m to 44 m depth and 3 deg 53.8' W and 54 deg 25.4' N, (and borehole 71/41 but no depths), in conjunction with NIREX seismic line 89/29 shotpoints 2621 to 2630. NIREX 1997 a, b. |
| Reference Section |
Offshore BGS borehole No. 71/64 at 5 m to 28 m depth and 3 deg 56.4' W and 54 deg 29.1' N. |
| Reference(s): |
| Pantin, H M. 1978. Quaternary sediments from the north-east Irish Sea: Isle of Man to Cumbria. Bulletin of the Geological Survey of Great Britain, Vol 64, 1-43. |
| NIREX. 1997b. Interpretation of the BNFL/NIREX offshore high resolution seismic data. UK NIREX Ltd. Report No SA/97/042. |
| 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. |
| Jackson, D I et al. 1995. United Kingdom offshore regional report: the Geology of the Irish Sea (London: HMSO for the British Geological Survey). |
| NIREX. 1997a. A summary of the correlation and nature of onshore and offshore Quaternary sediments of the Sellafield area. UK NIREX Ltd. Report No SA/97/042. |
| 1:50K maps on which the lithostratigraphical unit is found, and map code used: |
|
E037
|
