On a warm June day, Colchester young archaeologists' club gathered on the Essex coast to comb the beach for fossils. One of our volunteers had prepared a check sheet for finds of such things as fossil shells from the red crag, fossil wood and sharks teeth. Everything was carefully checked by an expert on hand, who explained the geology of the coast and how and why there were so many interesting things we could discover, from thousands to millions of years ago. The tide came in earlier than anticipated, but that gave us an opportunity to examine the fossilised wood from monkey puzzle trees. sharks teeth, a fresh water snail shell fossil and a tiny fossil fish tail discovered in the shingle on the beach, among many other things. Below is a picture of these extraordinary cliffs with a key to the features.
A Glacial sand and gravel on which you can see ice wedges. During the devensian period, 100,000 years ago.
B Grey/green clay sediment from a large river the Medway/Thames ran to confluence with the proto Rhine 500,000 years ago. This is the era of the first settlers "Clactonians."
C Red crag proper, showed cross bedding that tells us of rough water conditions. Deposited as a sand bank.
- - - Waltonian sub stage of late Pliocene early Pleistocene 2.5 million years ago.
D junction bed of the believed Miocene period 12 million years ago.
E London clay with volcanic ash. 53.7 million years ago.
Thank you to Wayne Dutnall who helped us find and identify fossils on the Essex coast and who has supplied this picture of the cliffs with an analysis of the geology and age of the stratas.
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