| Computer Code: |
YV |
Preferred Map Code: |
notEntered |
| Status Code: |
Full |
| Age range: |
Pleistocene Epoch (QP)
— Holocene Epoch (QH) |
| Lithological Description: |
The formation encompasses the fluvial, lacustrine and organic deposits of the River Yare. It includes floodplain alluvium and a restricted development of river terrace deposits. The floodplain alluvium comprises soft clays, silts and fine-grained sands, with bodies of peat, overlying fine- to coarse-grained sands and gravels. These gravels are mostly composed of rounded flint pebbles and cobbles, with a little chalk, rarely shelly but commonly silty. The gravels commonly occur in buried channels overlain by the Breydon Formation. River terrace deposits are largely gravel and sand. The gravel is dominated by subangular to rounded flint, including large cobbles, with some pebbles of quartz and quartzite. Gravelly sediments belonging to this formation have been recorded in boreholes offshore. |
| Definition of Lower Boundary: |
Unconformable upon glacial and solifluction deposits and upon Crag Group, London Clay Formation and Chalk Group bedrock. |
| Definition of Upper Boundary: |
Surface, or overlain by deposits of the Breydon Formation. |
| Thickness: |
About 18 m. |
| Geographical Limits: |
The valley of the River Yare and its minor tributaries, from near Shipdham to its mouth at Great Yarmouth, Norfolk, and also the offshore extensions of the buried valley of the River Yare, but not including the valleys of the rivers Bure and Waveney and their tributaries. |
| Parent Unit: |
Yare Catchments Subgroup (YCAT)
|
| Previous Name(s): |
none recorded or not applicable
|
| Alternative Name(s): |
none recorded or not applicable
|
| Stratotypes: |
| Type Section |
Runham/Yare Borehole 8 (TG50NW/480) (Arthurton et al., 1994). |
| Reference(s): |
| Funnell, B M. 1985. The Yare buried glacial channel. Transactions of the Norfolk Naturalists' Society, Vol.18. 10-14. |
| Cox, F C, Gallois, R W, and Wood, C J. 1989. Geology of the country around Norwich. Memoir of the British Geological Survey, Sheet 161 (England and Wales). |
| Arthurton, R S, Booth, S J, Morigi, A N, Abbott, M A W, and Wood, C J. 1994. Geology of the country around Great Yarmouth, Sheet Memoir 162, British Geological Survey. [London: HMSO.] 138pp. |
| McMillan, A A, Hamblin, R J O, and Merritt, J W. 2011. A lithostratigraphical framework for onshore Quaternary and Neogene (Tertiary) superficial deposits of Great Britain and the Isle of Man. British Geological Survey Research Report, RR/10/03. 343pp. |
| 1:50K maps on which the lithostratigraphical unit is found, and map code used: |
|
E162
E132
E148
E176
|
