||Preferred Map Code:
||Thanetian Age (GT)
— Ypresian Age (GY)
|| Vertically and laterally variable sequences mainly of clay, some silty or sandy, with some sands and gravels, minor limestones and lignites and occasional sandstone and conglomerate.
|Definition of Lower Boundary:
|| The base of the Lambeth Group is taken at the base of the Upnor Formation. In the Hampshire Basin and the west of the London Basin, the Lambeth Group overlies the Chalk Group. In the centre and east of the London Basin it overlies the Thanet Formation, and in Suffolk the Ormesby Clay Member of the Lista Formation.
|Definition of Upper Boundary:
|| The top of the Lambeth Group is marked by the eroded or interburrowed surface at the base of the overlying Thames Group. The uppermost part of the Lambeth Group can be the Reading Formation or the Woolwich Formation, depending on the local succession, or the Upnor Formation, depending on the depth of pre-Thames Group erosion. The Lambeth Group is overlain by sands, silts, clays or gravel beds of the Harwich Formation, depending on the local sequences, or gravelly sandy clays at the base of the London Clay Formation.
|| Up to 39m in the west of the London Basin.
|| The Lambeth Group extends throughout the London Basin, extending north into Suffolk. The Lambeth Group also occurs within the Hampshire Basin, where it mostly comprises only the Reading Formation, although there is a thin representation of the Upnor Formation, and the Woolwich Formation forms small outliers in the most easterly parts of the onshore outcrop.
Not Applicable (-)
|| Woolwich And Reading Beds
none recorded or not applicable
||The type area is in the London Basin, specifically central and south London and north Kent.
|Knox, R W O. 1996. Tectonic controls on sequence development in the Palaeocene and earliest Eocene of southeast England: implications for North Sea stratigraphy. 209-230 in Sequence Stratigraphy in British Geology. Hesselbro, S P, and Parkinson, D N (editors). Geological Society of London Special Publication, No. 103.
|Ellison, R A, Knox R W O'B, Jolley, D W and King, C, 1994. A revision of the lithostratigraphical classification of the early Palaeogene strata of the London Basin and East Anglia. Proceedings of the Geologists' Association, Vol.105, 187-197.
|Aldiss, D.T., 2012. The stratigraphical framework for the Palaeogene successions of the London Basin, UK. British Geological Survey Open Report OR/12/004. Available from http://nora.nerc.ac.uk/17121/.
|Ellison, R.A., 1983. Facies distribution in the Woolwich and Reading Beds of the London Basin, England. Proceedings of the Geologists' Association 94, 311-319.
|Hester, S W. 1965. Stratigraphy and palaeogeography of the Woolwich and Reading Beds. Bulletin of the Geological Survey of Great Britain No. 23, 117-137.
|Page, D P, and Skipper, J A E. 2000. Lithological characteristics of the Lambeth Group. Ground Engineering, Vol. 33, 38-43.
|Ellison, R A, Woods, M A, Allen, D J, Forster, A, Pharaoh, T C and King, C. 2004. Geology of London. Memoir of the British Geological Survey, Sheets 256 (North London), 257 (Romford), 270 (South London), 271 (Dartford) (England and Wales).
|1:50K maps on which the lithostratigraphical unit is found, and map code used: