The BGS Lexicon of Named Rock Units — Result Details
Woolwich Formation
| Computer Code: | WL | Preferred Map Code: | WL |
|---|---|---|---|
| Status Code: | Full | ||
| Age range: | Thanetian Age (GT) — Ypresian Age (GY) | ||
| Lithological Description: | The Woolwich Formation is typically composed of either dark grey shelly clay, laminated clay and silt or fine- to coarse-grained sand. Sporadic burrows occur throughout but bioturbation is more common in the higher beds, where sparse glauconite has been recorded. Shelly beds, particularly in the basal 2 m, are dominated by brackish water shells in dark grey clay matrix. Common plant debris is concentrated locally in thin allochthonous lignites, especially near the base. Very sparse occurrences of thin degraded ash deposits have been noted in south London and north-west Kent (King, in prep.; Knox and Morton, 1983). The Woolwich Formation represents a variety of marginal marine facies of the Lambeth Group, with occasional freshwater incursions. Most, if not all, of the Woolwich Formation was deposited during the Early Eocene (earliest Ypresian). It possibly includes latest Paleocene deposits in the Shorne Member (Collinson et al., 2003). | ||
| Definition of Lower Boundary: | The Woolwich Formation rests either on red-brown, yellow-brown and blue-grey mottled clays (Reading Formation) or glauconitic sands (Upnor Formation). The base is sharp, with burrows extending as much as 0.5 m into the underlying beds. The boundary with the Reading Formation in central and southeast London is very well defined and, as lithological and colour contrasts are pronounced, can be interpreted readily in most drillers' logs. | ||
| Definition of Upper Boundary: | Most typically, the top of the Woolwich Formation is marked by a change from fine-grained sands, silts or clays to glauconite-bearing sands, silts or clays with a basal rounded flint gravel bed and a marine fauna, or sandy flint gravels (Harwich Formation). In parts of central London, where the Upper Shelly Clay and Striped Loams are absent, the Woolwich Formation is overlain by the upper part of the Reading Formation. Here there is a change from mainly grey, thinly bedded to laminated fine-grained sands, silts and clays, to vari-coloured, mottled clays. | ||
| Thickness: | Maximum 14.5 m; generally 11 to 12 m in south-east London and north Kent; thins to the west and north as it is replaced laterally by the Reading Formation. | ||
| Geographical Limits: | The Woolwich Formation occurs mainly in the central and eastern parts of the London Basin. Outliers occur near Newhaven in East Sussex, in the easternmost onshore extent of the Hampshire Basin (Dupuis and Gruas-Cavagnetto, 1985). | ||
| Parent Unit: | Lambeth Group (LMBE) | ||
| Previous Name(s): | Woolwich Beds [Obsolete Name and Code: Use WL]
(-3131)
Woolwich Facies [Obsolete Name and Code: Use WL] (-4402) |
||
| Alternative Name(s): | none recorded or not applicable | ||
| Stratotypes: | |||
| Reference Section | Lower Upnor Pit, north of Chatham, Kent [TQ 759 711] (Daley, 1999b; Ellison et al., 1994; Kennedy and Sellwood, 1970). | ||
| Type Section | Type section: Charlton Pit (or Gilbert's Pit), just south-west of Maryon Park, Charlton, London Borough of Greenwich [TQ 418 786] (Daley, 1999b; Ellison et al., 1994; Whitaker, 1889). The Woolwich Formation comprises Units 2 to 6 of Whitaker (1889, p. 147-148). | ||
| Reference Section | Channel Tunnel Rail Link (CTRL) Borehole A2 (TQ38SW 2212) [TQ 3296 8051], London, 40.22 to 41.91 m depth (Ellison et al., 1994). | ||
| Reference Section | Jubilee Line Extension Borehole 404T (TQ37NW 2118) [TQ 33638 79604], Bermondsey, London, 29.63 to 33.77 m depth (Ellison et al., 1994). | ||
| Reference(s): | |||
| Ellison, R A, 1983. Facies distribution in the Woolwich and Reading Beds of the London Basin, England. Proceedings of the Geologists' Association, Vol. 94, 311-319. | |||
| 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. | |||
| Waters, C N, Smith, K, Hopson, P M, Wilson, D, Bridge, D M, Carney, J N, Cooper, A H, Crofts, R G, Ellison, R A, Mathers, S J, Moorlock, B S P, Scrivener, R C, McMillan, A A, Ambrose, K, Barclay, W J, and Barron, A J M. 2007. Stratigraphical Chart of the United Kingdom: Southern Britain. British Geological Survey, 1 poster. | |||
| Aldiss, D T. 2014. The stratigraphical framework for the Palaeogene successions of the London Basin, UK. British Geological Survey Open Report OR/14/008. 95 pp. | |||
| Collinson, M.E., Hooker, J.J., Gröcke, D.R., 2003. Cobham Lignite Bed and penecontemporaneous macrofloras of southern England: a record of vegetation and fire across the Paleocene-Eocene Thermal Maximum, In: Wing, S.L., Gingerich, P.D., Schmitz, B., Thomas, E. (Eds.), Causes and consequences of globally warm climates on the Early Paleogene. Geological Society of America Special Papers 369, pp. 339-349. | |||
| Daley, B. 1999. London Basin: eastern localities, In: Daley, B, Balson, P (Eds.), British Tertiary Stratigraphy. Geological Conservation Review Series 15, pp. 23-72. | |||
| Dupuis, C., Gruas-Cavagnetto, C., 1985. The Woolwich Beds and the London Clay of Newhaven (East Sussex): new palynological and stratigraphical data. The London Naturalist 75, 27-39. | |||
| 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). | |||
| Hooker, J J. 2010. The mammal faunas of the early Eocene Blackheath Formation of Abbey Wood, London. Monograph of the Palaeontographical Society, London, 164, 1-162. | |||
| Kennedy, W.J., Sellwood, B.W., 1970. Ophiomorpha nodosa Lundgren, a marine indicator from the Sparnacian of south-east England. Proceedings of the Geologists' Association 81, 99-110. | |||
| King, C. in prep. A revised correlation of Palaeogene and Neogene deposits in the British Isles. Geological Society of London Special Report. | |||
| Knox, R W O, and Morton, A C. 1983. Stratigraphical distribution of Early Palaeogene pyroclastic deposits in the North Sea Basin. Proceedings of the Yorkshire Geological Society, Vol. 44, 355-363. | |||
| Prestwich, J, 1854. On the structure of the strata between the London Clay and the Chalk etc, part 11. The Woolwich and Reading Series. Quarterly Journal of the Geological Society, Vol.10, p.77. | |||
| Whitaker, W., 1889. The geology of London and part of the Thames Valley (Explanation of Sheets 1, 2 and 7). Memoir of the Geological Survey of the United Kingdom Vol. 1. Descriptive geology. | |||
| 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. | |||
| 1:50K maps on which the lithostratigraphical unit is found, and map code used: | |||
| E256 E257 E258 E259 E271 E272 E273 E274 | |||