434 



EOCENE. 



lying the Oldhaven Beds. The name Oldhaven Beds is taken 

 from Oldhaven Gap, on the coast of Kent, west of Reculvers, where 

 the beds are well displayed. The term Blackheath Beds is also 

 employed from Blackheath in the same county.^ 



The formation consists largely of flint- 

 pebbles in a fine sandy base, or of fine sharp 

 light-coloured quartzose sand, and it occasion- 

 ally contains limonite. Current-bedding is 

 displayed in places. Sometimes the pebble- 

 beds are cemented into a hard rock, or 

 pudding-stone ; and in East Kent the sand is 

 occasionally indurated. The total thickness 

 of the beds varies from a few feet to 60 feet. 

 ^ R P* In the neighbourhood of Canterbury, at 



Shottenden Hill, near Sittingbourne and 

 Rochester, at Plumstead Common, Abbey 

 Wood, Blackheath, Greenwich (30 to 40 feet), 

 and Woolwich, the beds are well displayed. 

 They thin out in the neighbourhood of Lewis- 

 ham, and are not met with under London, nor 

 O t'V)Wv-l .o,i;\';f>l-C> iri the western part of the London Basin; but 

 they have been met with in South Essex and 

 at Ipswich.^ 



The Oldhaven Beds are sometimes fossil- 

 iferous. The fossils are partly fluviatile and 

 estuarine and partly marine, being sometimes 

 of the same species as those of the Woolwich 

 Beds below, and sometimes more nearly 

 approaching those of the London Clay above, 

 seeming therefore to prove oscillations of 

 surface or changes of current and nearness to 

 land, conditions which might also be expected 

 from the masses of pebbles. There are no 

 distinctive organic remains. The Bromley leaf- 

 -^ /?f'-''Pct beds (Widmore pit) are regarded by Mr. 

 Whitaker as belonging to an Oldhaven fresh- 

 water series ; Mr. J. S. Gardner, however, 

 places them with the Woolwich Beds. It 

 would seem that the pebble-beds were not 

 formed as a beach along a chalk-shore, as 

 in that case they should contain many flints 

 but partly worn, and Mr. Whitaker therefore 

 infers that they must have been deposited some way off the shore, 

 as a bank to which no flints could get until after having been long 

 exposed to wearing action. In some places the strata rest 



^ W. Whitaker, Q. J. xxii. 412, xxxix. 2IO ; Mem. Gaol. Surv. iv. 239 ; see 

 also J. S. Gardner, Q. J. xxxix. 205. The term Blackheath Sand was used by 

 WilHam Smith. 



^ Whitaker, Geol. Ipswich, p. i5- 



