The BGS Lexicon of Named Rock Units — Result Details

Woolwich Formation

Computer Code: WL Preferred Map Code: WL
Status Code: Full
Age range: Paleocene Epoch (GP) — Paleocene Epoch (GP)
Lithological Description: Variable: largely grey to grey-brown, interlaminated fine-grained sands, silts and clays (also known as "Striped loams" (eg Dewey and others, 1924). Common plant debris concentrated locally in thin allochthonous lignites. Sporadic burrows throughout; bioturbation more common in higher beds, where sparse glauconite has been recorded. Shelly beds, particularly in the basal 2m, dominated by brackish water shells in dark grey clay matrix ("Woolwich Shell Bed"). Other lithofacies of local occurrence are limestone beds such as the "Paludina Limestone" (eg Berry and Cooper, 1977) at the top of the formation, and ferruginous sand and pebble beds (Ellison, 1983). Woolwich Formation not shown previously on maps.
Definition of Lower Boundary: Rests either on red-brown, yellow-brown and blue-grey mottled clays (Reading Formation) or glauconitic sands (Upnor Formation). Base sharp, with burrows extending up to 0.5m 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: Other than in central London, where the formation is overlain by the Reading Formation, the top is marked by a change to glauconite-bearing sands with a basal rounded flint pebble bed and a marine fauna (Harwich Formation).
Thickness: Maximum 14.5m; generally 11 to 12m in southeast London and north Kent; thins to the west and north as it passes into the Reading Formation.
Geographical Limits: Not defined.
Parent Unit: Lambeth Group (LMBE)
Previous Name(s): Striped Sands (-3130)
Woolwich Beds (-3131)
Woolwich Facies (-4402)
Woolwich Beds-Oldhaven Beds [Obsolete Name And Code: see WL and OH] (WLOH)
Alternative Name(s): none recorded or not applicable
Stratotypes:
Type Section  Charlton Pit, near Maryon Park, Charlton, southeast London. 
Reference Section  Jubilee Extension Borehole 404T. BGS Registration No. TQ37NW/2118 
Reference Section  Lower Upnor Pit, north of Chatham, north Kent. 
Reference(s):
Dewey, H, Bromehead, C E N, Chatwin, C P and Dines, H G. 1924. The geology of the country around Dartford. Memoir of the Geological Survey, Sheet 271 (England and Wales). 
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. 
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. 
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. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
E256 E257 E258 E259 E271 E272 E273 E274