SWANSCOMBE MAN THE OLDEST BRITON BUT NOT AS OLD AS ONCE BELIEVED: URANIUM SERIES CHRONOLOGY OF TOOTH ENAMEL FROM THE MIDDLE GRAVELS, BARNFIELD PIT, KENT, GREAT BRITAIN

Uranium Series analysis of six teeth provided by the British Museum from the Swanscombe Man site (Barnfield Pit, Kent, Great Britain) support the presence of a channel deposit (Upper Middle Gravels and Middle Gravels) incised into older gravels (Lower Gravels). Tooth enamel provides a generally closed system compared to that of bone and dentine which are often open to Uranium gain and loss from the encasing sediments. The Uranium ratio (²³⁴U/²³⁸U) in the Middle Gravels was lower (average 1.0 to 1.2) than in the Lower Gravels (1.20 to 1.35) suggesting different water sources. The analysis determined that the Middle Gravels (Mammoth; Palaeoloxodon antiguus [M14722] and Bovid enamel) date from 127,000 to 155,000 years BP (although one result from the Upper Middle Gravels [Horse enamel] was older at 183,000 years BP) while the Lower Gravels range (Mammoth; Palaeoloxodon antiguus [M18637], Horse, and Bovid enamel) from 180,000 to about 286,000 years BP. The Swanscombe Man skull fragments (Homo sp.?) are associated with the Middle Gravels which date to between 127,000 to 183,000 years BP. Previous Uranium Series analysis using bone indicated ages of greater than 300,000 years BP for the Middle Gravels. That finding is not supported. Swanscombe Man the oldest Briton but not as old as once believed.