Geology Site Account

Historical sites only

London Clay gives rise to low, subdued topography and a good example of this is the area between Romford and Basildon. In the Borough of Havering there have been temporary exposures of London Clay from time to time, some of which have occurred in the most unlikely places. For example, in 1971, in a housing estate in Cranham (TQ 574 884), a roadside excavation for a new sewer produced fossils from the London Clay that included a crab, a brachiopod and tubes made by a marine worm.

Several years later, in 1980-81, construction of the M25 motorway created a number of spectacular exposures on the London-Essex border, the largest of which was the giant Nags Head Lane cutting (see separate entry under Harold Wood) and the deep cutting at Beredens Lane (TQ 577 898), the latter revealing stiff, silty clay at the very highest levels of the London Clay and containing two prominent layers of septarian nodules.

During the same period, at the M25 Codham Hall interchange (TQ 585 885), the north face of the cutting for the A127 Southend Arterial Road produced fossil crabs, lobsters and other molluscs.

West of the interchange a particularly interesting find was made in the piles of excavated London Clay on the side of the A127 at Folkes Lane (TQ 580 884) in the form of a rare fossil lobster (Glyphea scabra) that is still one of only four specimens of this species known to science. The lobster and the other fossils collected here are currently in the collections of the Essex Field Club (formerly in the Passmore Edwards Museum).