| Computer Code: |
BLYV |
Preferred Map Code: |
notEntered |
| Status Code: |
Full |
| Age range: |
Mid Pleistocene (QPM)
— Holocene Epoch (QH) |
| Lithological Description: |
The formation encompasses the fluvial, lacustrine and organic deposits of the rivers that flow into the North Sea along the coast of north Norfolk. It includes floodplain alluvium and a restricted development of river terrace deposits. The floodplain alluvium comprises soft clays, silt and fine-grained sands, with bodies of peat, overlying fine- to coarse-grained sands and gravels. River terrace deposits are largely gravel and sand. The gravels are dominated by subangular to rounded flint, including large cobbles, but also include rounded pebbles pf quartz and quartzite, northern British erratics of glacial derivation, and a little chalk. |
| Definition of Lower Boundary: |
Unconformable on glacial and solifluction deposits and on Crag Group and Chalk Group bedrock. |
| Definition of Upper Boundary: |
Surface. |
| Thickness: |
c.5m |
| Geographical Limits: |
North Norfolk, north of the watershed defining the catchment of the River Bure. |
| Parent Unit: |
Yare Catchments Subgroup (YCAT)
|
| Previous Name(s): |
none recorded or not applicable
|
| Alternative Name(s): |
none recorded or not applicable
|
| Stratotypes: |
| Type Area |
The valley of the River Glaven, North Norfolk. Moorlock et al., 2002. |
| Reference(s): |
| Moorlock, B S P, Hamblin, R J O, Booth, S J, Kessler, H, Woods, M A and Hobbs, P R N. 2002. Geology of the Cromer district - a brief explanation of the geological map. Sheet explanation of the British Geological Survey. 1:50 000 Sheet 131 Cromer (England and Wales). |
| 1:50K maps on which the lithostratigraphical unit is found, and map code used: |
|
E130
E131
E132
|
