| Computer Code: |
KSDSG |
Preferred Map Code: |
notEntered |
| Status Code: |
Full |
| Age range: |
Late Pleistocene (QPL)
— Late Pleistocene (QPL) |
| Lithological Description: |
Predominantly cold-phase sands and gravels representing the youngest deposits of the Proto-Trent, and the pre-Flandrian deposits of the Witham. The former are typically dominated by rounded pebbles of "Bunter" quartz/quartzite with subordinate subangular flint, etc. but the latter have a greater proportion of flint and local Jurassic limestone, etc. Surface c. 1 to 2 m above the Trent floodplain, at Spalford, and typically 3 to 6 m below Witham floodplain level in the Type Area. West of the Lincoln Gap, correlated with the Holme Pierrepont Member (Trent Valley Formation); whilst east of Lincoln Gap also includes older materials correlated with the Scarle and Fulbeck Sand and Gravel members (Trent Valley Formation) and Castle Sand and Gravel Member (Bain Valley Formation).
Upper Pleistocene (MI Stage 2 west of the Lincoln Gap, or 5e to 2 east of the Lincoln Gap). The chronology is based on the assumption that west of the Lincoln Gap (where Scarle Sand and Gravel can be separated) it is broadly correlative with the Holme Pierrepont of the Trent, whereas east of the Gap it includes everything that is Ipswichian or later, thus including correlatives of the Scarle Sand and Gravel, as in the Castle Sand and Gravel Member of the Bain. |
| Definition of Lower Boundary: |
Unconformable, commonly channelled base, resting on pre-Quaternary bedrock or Wragby Till Member (Lowestoft Formation). |
| Definition of Upper Boundary: |
Ground surface or base of alluvium or blown sand (Spalford Member). |
| Thickness: |
0 to c. 8.5 m; typically 4 to 5 m. |
| Geographical Limits: |
Comprises the younger, mainly Devensian fluvial deposits (i.e. excluding Flandrian alluvium) of the Witham catchment and of the Proto-Trent area (i.e. east of the Trent between Newark to Gainsborough). Note that adjoining the Trent the deposits could be classified mainly as Holme Pierrepont Sand and Gravel but the limits suggested above are an attempt to indicate a possible boundary line on the basis of this definition. The unit is not delineated as such on any published BGS map. |
| Parent Unit: |
Trent Valley Formation (TRVA)
|
| Previous Name(s): |
Kirkstead Member [Obsolete Name and Code: Use KSDSG]
(-2885)
|
| Alternative Name(s): |
none recorded or not applicable
|
| Stratotypes: |
| Type Area |
Lower Witham valley, Martin Fen area (west of Woodhall Spa). Jackson, 1982. |
| Type Section |
BGS Martin South Drove Borehole (TF16SE/32) near Woodhall Spa 4.9 to 14.7 m depth. Jackson, 1982. |
| Reference(s): |
| Edwards, W N, 1967. Geology of the country around Ollerton (2nd edition). Memoir of the Geological Survey of Great Britain, sheet 113 (England and Wales). |
| Gozzard, J R. 1975. The sand and gravel resources of the country around Besthorpe, Nottinghamshire: description of 1:25 000 resource sheet SK86 and part of SK76. Mineral Assessment Report, Institute of Geological Sciences, No.17. |
| Jackson, I. 1977. The sand and gravel resources of the country west and south of Lincoln, Lincolnshire: description of 1:25 000 resource sheets SK95 and part of SK96 and SK97. Mineral Assessment Report, Institute of Geological Sciences, No.27. |
| Jackson, I. 1982. The sand and gravel resources of the country north and west of Woodhall Spa, Lincolnshire: description of 1:25 000 resource sheet TF16 and part of TF17. Mineral Assessment Report, Institute of Geological Sciences, No.94. |
| Price, D. 1975. The sand and gravel resources of the country around Newton on Trent, Lincolnshire: description of 1:25 000 resource sheet SK87. Mineral Assessment Report, Institute of Geological Sciences, No.15. |
| Bowen, D Q. 1999. A revised correlation of Quaternary deposits in the British Isles. Geological Society Special Report, No. 23. |
| 1:50K maps on which the lithostratigraphical unit is found, and map code used: |
|
E101
E102
E103
E113
E114
E115
E127
E128
E143
|
