Computer Code: |
TIMW |
Preferred Map Code: |
notEntered |
Status Code: |
Full |
Age range: |
Mid Pleistocene (QPM)
— Mid Pleistocene (QPM) |
Lithological Description: |
Fluvial sand and gravel containing quartzite, vein quartz, flint and chalk. Terrace of the pre-Anglian River Bytham. Base of the terrace lies at 12-18 m OD. |
Definition of Lower Boundary: |
Unconformably overlies Chalk bedrock. |
Definition of Upper Boundary: |
Unconformably overlain by a variety of superficial deposits which include sand and gravel and till of the Lowestoft Formation. Overlying sands and gravels are less well sorted. |
Thickness: |
Up to about 10 m. |
Geographical Limits: |
Restricted to the valley of the palaeo-river Bytham in Suffolk. Not depicted separately on BGS maps. |
Parent Unit: |
Ingham Sand and Gravel Formation (ISAG)
|
Previous Name(s): |
none recorded or not applicable
|
Alternative Name(s): |
none recorded or not applicable
|
Stratotypes: |
Type Section |
Sand and gravel pit adjacent to 'Beightons', near Timworth (Lewis and Bridgland, 1991). |
Reference(s): |
Lewis, S J and Bridgland, D R. 1991. Ingham and Timworth. 71-83 in Lewis, S J, Whiteman, C A, and Bridgland, D R (editors), Central East Anglia and the Fen Basin. Field Guide. [London: Quaternary Research Association.] |
Lewis, S G. 1993. The status of the Wolstonian glaciation in the English Midlands and East Anglia. PhD Thesis, University of London. |
Bowen, D Q. 1999. A revised correlation of Quaternary deposits in the British Isles. Geological Society Special Report, No. 23. |
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: |
none recorded or not applicable |