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The Essex Naturalist
The Hoxnian deposits immediately post-date the Anglian deposits and so are
correlated with OIS 11. There is some contention about this as amino acid age
determinations on mollusca from Hoxne itself give ratios of 0.25 which would
suggest OIS 9. As the amino acid data is at variance with several other lines of
evidence, it is noted but usually not used. The presence of
Clactonian/Acheulian artefacts would support a dating of this age.
The overlying gravels are ascribed, therefore, to OIS 10.
Corbets Tey Formation
At Purfleet and Belhus Park in south Essex, interglacial silts yielding artefacts,
molluscs, Ostracods and pollen have been found beneath and within these
gravels. The age of the silts is subject to debate. The pollen suggests an
Ipswichian age, but the altitude of the gravels, the molluscs (including Corbicula
fluminalis), fauna (including mammoth and horse)and amino acid ratios (>0.23)
suggest an age older than for the deposits at Aveley and Trafalgar Square (see
above). The basal gravels yield Clactonian/Acheulian artefacts and the upper 
gravels Levallois forms. The basal gravels, where present, are considered to be
the 'fill' part of the OIS 10 cut and fill sequence, the overlying intetglacial
deposits as OIS 9, and the uppermost gravels as OIS 8.
Mucking Formation
At Aveley a rich yield of pollen, vertebrates, molluscs and Ostracods has been
obtained from silts beneath gravels. The pollen does not distinguish between the
deposits here and those from lower elevations, such as Trafalgar Square in
London. However, Sutcliffe and others argue that the vertebrates do indicate that
the higher deposits are older (with horse and mammoth but lacking
Hippopotamus). Corbicula fluminalis is present and recently Ward found Levallois
type artefacts beneath the interglacial deposits. The amino acid ratios (0.15-0.19)
are in the range expected for OI. Stage 7. Thus the basal sands and gravels are
assigned to the OI. Stage 8 cold period, the interglacial; deposits to Stage 7 and
the overlying gravels to Stage 6.
Kempton Park Gravel
The Kempton Park Gravel abuts against the Ipswichian deposits of Trafalgar
Square. Two radio-carbon dates from material within the gravels give dates of
35,230 and 43,140 BP, indicating that the aggradation occurred in the middle
Devensian. Amino acid ratios of 0.11 conform to those expected OI. Stage 5e.
Hippopotamus is present, while horse, mammoth and Corbicula fluminalis are absent.
Summary
During the last two or three years, much work has been carried out in the
Aveley and Purfleet areas in connection with the new A13 road alignment and
in quarries in the Watts Wood area by Schreve, Allen, Haggart, Ward, George
and others. Their findings, when processed and interpreted, will add greatly to