GLACIAL STRATIGRAPHY OF WEST ESSEX 329
(Wooldridge, 1957; Clayton, 1960, 1964), although satisfying cer-
tain correlative conditions, are really unjustifiable from the local
stratigraphic and morphological evidence.
Conclusion
The present data favour the essential unity of the west Essex
Chalky Boulder clay, being the product of a single glaciation but
certainly involving fluctuations in the detailed position of the ice
margin. Whether this glaciation is of Lowestoft or Gipping age
cannot be stated without reference to a local interglacial datum,
for which there is, as yet, no evidence. The Coopersale Common
"head" may prove to belong to a pre-Chalky Boulder clay glaci-
ation of westerly provenance; but again its precise age relations
can only be surmised in the absence of an interglacial horizon.
More confidently it can be stated that the Hanninfield-Spring-
field distinction of south Essex is inapplicable to the west Essex
situation and that the Maldon Till, in all probability, represents
no more than a minor advance phase of the main Chalky Boulder
clay glaciation.
Acknowledgments
I would like to acknowledge with gratitude the kindness and
assistance of the Ministry of Transport and their Consulting
Engineers for the M.11 project (Messrs W. S. Atkins & Partners,
Epsom) in allowing me complete access to the M.11 Soil Survey
records. In addition, I would like to express my thanks to Dr C.
Embleton who read and commented on the original draft.
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