THE GEOLOGY AND ARCHAEOLOGY
OF THE DISTRICT OP
WALTON-ON-NAZE and CLACTON-ON-SEA.
By H. Stopes, F.G.S., & W. H. Dalton, F.G.S.
Certain points connected with the geology and
archaeology of this district are so prominent as to
attract the attention of most visitors, whether con-
versant with that science or no. Such are the deposit of
sea-shells constituting the upper part of the cliff at
Walton-on-Naze, the old forest exposed at low tide
near Clacton, the long spit of sand and shingle known
as St. Osyth Beach, and the Salting-Mounds of
Mersea and Wigborough.
It has been thought, therefore, that a brief sketch
of the geology of the neighbourhood may be useful
and interesting, both to those who, without penetra-
ting deeply into the subject, would like a short ex-
planation of the phenomena attracting their attention,
and to those who desire more thoroughly to investi-
gate the local geology.*
Geological Formations.
The beds that occur at the surface in this tract are
as follow :—
Besides these, however, lower beds have been
pierced in the deep wells, one of which at Harwich
reaches even to Palaeozoic rocks, the series thus con-
tinued beneath the London clay being:—
The chief interest of theae centres in the Pliocene
and Post-Glacial beds, as mentioned above.
London Clay.—This well-known clay not only forms
the surface of the greater part of the district, but also
everywhere underlies the newer beds. It is more or
less bedded in structure, and dark bluish-grey in color,
* Fuller details than those given below must be sought for
in the maps and memoirs of the Geological Survey Quarter-
Sheets, 48 S.W. and S.E. Price 3s. each ; memoirs 1s. and 9d.
respectively.