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separating the gravels from the outwash and tills, ruling out the possibility of a link on temporal
as well as lithological grounds.
The history of research into the tills of East Anglia has passed through a complete cycle, initially
favouring one ice advance, then several, and now one again (summarised in Allen et al, 1991).
In Essex up to three tills have been recognised.
The Springfield Till (Chalky Boulder Clay) was considered to be the main till of the county
(Whitaker, 1889; Clayton, 1957a, 1960). In the Maldon area, a lower till (Maldon Till) was
recognised within gravels below the main till. Tills in a similar stratigraphic position to the
Maldon Till were found also at Harlow (Clayton, 1957a), Braintree (Clarke and Ambrose,
1975), Witham and possibly Great Totham (Haggard, 1972). A further till was recognised on
interfluves as far south as Hanningfield (Hanningfield Till). The weathered nature of this till
and its hilltop position, suggested it was older than the others, pre-dating the formation of the
valleys along which the other tills were found. Associated with the tills were outwash gravels,
the Chelmsford and Danbury Gravels.
A complication about the till sequence outlined by Clayton was the difficulty he had matching
his stratigraphy with that of East Anglia. When Clayton first published his views in 1957, he
proposed three tills when only two were recognised in East Anglia, the Lowestoft (Anglian) and
Gipping ('Wolstonian') Tills. As the Hanningfield Till was thought to be markedly older than
the others, it was correlated with the Anglian and the others with the Saalian of the continent (=
'Wolstonian'). However, he later (1960) changed his views to correlate better with those of
Baden-Powell (1948), West and Donner (1956) and Wooldridge (1957), linking the
Hanningfield Till with the Cromer Till and the Chiltern Drift (both of uncertain age), the
Maldon Till with the Lowestoft Till (Anglian) and the Springfield Till with the Gipping Till
('Wolstonian').
However, Turner (1970) found polleniferous deposits at Marks Tey and Rivenhall End of
Hoxnian age with no later deposits above. This indicated that a glacier of 'Wolstonian' age
could not have crossed the area and revivified the view that the Maldon Till was merely a
precursor of the more important Springfield Till. Subsequent work by the British Geological
Survey (Bristow and Cox, 1973; Bristow, 1985; Lake et al., 1986) indicated that the
Hanningfield Till was in fact a weathered variant of the Springfield Till or solifluction. Thus ice
advance only in the Anglian came to be accepted. This was confirmed when the tills were
demonstrated to be variants of the one sheet on the basis of the heavy minerals (Perrin et al.,
1973; Perrin et al., 1979)
In the central and western part of the county, a pebbly clayey deposit, variously known as the
Pebble Gravel (Whitaker. 1880; Prestwich, 1890; Wells and Wooldridge, 1923; Warren. 1910.
1942; Dines and Edmunds, 1925; Sherlock and Pocock, 1924; French and Greensmith, 1968)
and Older Head (Millward et al., 1987), is found in plateau and interfluve positions. It has been
interpreted in various ways, including as till (Whitaker, 1889; Monckton, 1890). Detailed
examination by Baker (1971) and the British Geological Survey (Millward et al., 1987) show
that at least two variants of it can be recognised. A lower unit can be demonstrated to be more
pebbly and contain quartzose pebbles. This is now thought to be a degraded braided river
deposit which, on the basis of the erratics, may be part of the Kesgrave Gravels. The upper part
of the deposit is less stony and richer in clay. Millward et al (1987) tentatively suggest that it is
soliflucted Tertiary Claygate and Bagshot Beds, formed during the early Anglian periglacial
phase before the ice advanced. However, Baker (1971) suggests that some could be weathered
till.
Essex Naturalist (New Series) 16 (1999)