| Computer Code: |
LEHI |
Preferred Map Code: |
notEntered |
| Status Code: |
Full |
| Age range: |
Pleistocene Epoch (QP)
— Pleistocene Epoch (QP) |
| Lithological Description: |
Stratified and channelled proximal glaciofluvial outwash deposits. Lithologically, the gravels are rich in flint and quartzose clasts, and contain erratics of northern provenance including Old Red Sandstone, basaltic porphyry, dolerite and Carboniferous limestone. Palaeocurrent measurements reveal flow originally towards the northeast when constrained by the Bytham River valley, and then southwards as the river valley was infilled by outwash sediment. |
| Definition of Lower Boundary: |
The lower boundary of the Leet Hill Sand and Gravel Member truncates either the diamicton facies of the Corton Till Member or older stratified sands of the Wroxham Crag Formation sediments. Locally, such as at the stratotype, the outwash and underlying fluvial sediments (Bytham Catchments Subgroup) form a gradational fluvial to glacial outwash continuum. |
| Definition of Upper Boundary: |
The upper boundary of the Leet Hill Sand and Gravel Member with the overlying Corton Sand Member is abrupt but conformable. |
| Thickness: |
The deposit thickens westwards from Corton (0.8m) to around 9m in the vicinity of Leet Hill. |
| Geographical Limits: |
The deposit has been mapped extensively throughout the Yarmouth and Lowestoft districts. |
| Parent Unit: |
Happisburgh Glacigenic Formation (HPGL)
|
| Previous Name(s): |
none recorded or not applicable
|
| Alternative Name(s): |
none recorded or not applicable
|
| Stratotypes: |
| Type Section |
Leet Hill Quarry, Kirby Cane, near Beccles in south Norfolk where upto 6m of sand and gravel are exposed within the base of the quarry. They are overlain at the stratotype by the Leet Hill Sand and Gravel Member of the Happisburgh Glacigenic Formation. [NOTE - AN ERROR IS EVIDENT IN THE PRECEDING TEXT AND THIS IS CURRENTLY BEING QUERIED. LexMan, 10/10/06] Rose et al., 1999. |
| Reference(s): |
| Lee, J R, Rose, J, Hamblin, R J O and Moorlock, B S P. 2004. Dating the earliest lowland glaciation of eastern England: a pre-MIS 12 early Middle Pleistocene Happisburgh Glaciation. Quaternary Science Review, Vol.23, 1551-1566. |
| Rose, J, Lee, J R, Candy, I and Lewis, S G. 1999. Early and Middle Pleistocene river systems in eastern England: evidence from Leet Hill, southern Norfolk, England. Journal of Quaternary Science, Vol.14, 347-360. |
| Hopson, P M and Bridge, D M. 1987. Middle Pleistocene stratigraphy in the lower Waveney valley, East Anglia. Proceedings of the Geologists' Association, Vol.98, 171-185. |
| 1:50K maps on which the lithostratigraphical unit is found, and map code used: |
| none recorded or not applicable |
