Recent: A Neolithic transverse arrow head and a modern gun flint have also been collected
from the beach.
I am greatly indebted to the palaeoichthyologist, David J. Ward of Orpington, Kent for
kindly identifying and revising the list of fish remains.
Where do the Lower Tertiary fossils come from?
There are at least five possible sources for fossils found on the beach. Firstly they may
have been brought in as ships' ballast and dumped. A beautiful tooth of Carcharocles
megalodon was collected from Gravesend beach about thirty years ago. This had
apparently been brought from North America in ballast. There is no recent evidence of
the dumping of imported ballast on Harwich beach.
Secondly the fossils may be derived from material dredged from the harbour and dumped
on the beach. Again, there is no evidence of this being done recently. However, a local
resident has reported that as a child, shortly before the 1939-1945 war, she collected
pebbles and sharks teeth from the beach. She used these finds as stock for her toy shop.
She maintained that material was dredged from Harwich harbour to build up the beach.
Thirdly it may be being washed up. At the top of the beach adjacent to the sea wall
broken fragments of honeycomb worm tube (Sabellaria sp.) are abundant. This may be
seen today living at very low tide. However many of the teeth are in a mint unrolled
condition and do not appear to have been rolling about the beach gravel becoming
abraded.
Fourthly they may be coming from the "London Clay". However there is hardly any of
this deposit exposed on the beach or foreshore at present. At Harkstead, Suffolk a huge
"London Clay" foreshore platform is beautifully exposed. This has yielded a most
interesting fauna and flora, almost identical to that at Harwich beach, but the teeth occur
in much smaller numbers than at Harwich and several are impregnated with iron pyrite.
The Harwich fossils appear to be derived from a deposit of sand or silty sand. Sharks
teeth are scarce at Wrabness, Essex where the same horizon of "London Clay" is exposed.
Fifthly the fossils may be more or less in situ. A fault, with a small down throw to the
south, may run across the beach and foreshore just to the south of the low lighthouse at
Harwich. This may be supported by the way the Harwich Stone Band suddenly appears
to the south of the low lighthouse. There may be evidence of faulting from two wells in
West Street which were only 70 yards apart but where the Chalk surface was 20 feet
different while the "London Clay" deepened from 9 to 70 feet northwards over the same
distance (WH. Lindsey A Season at Harwich 1851 Researches p. 145). The apparently
localised occurrence of sandstone blocks and pebbles areas on the foreshore at extreme
low tide may support this idea. However the disappearance of the Harwich Stone Band
and the reduction in thickness of Tertiary deposits to the north may be due to extensive
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Essex Field Club Newsletter No. 48, September 2005