In the beginning...

.... there was clay.

Well, not quite, because before the clay there was lots of other stuff.

But Essex is famous for its clay and gravel, the results of successive periods of cooler and warmer climate when these layers were deposited. In fact, all the ‘rocks’ shown in the chart are the result of deposition, but only the top most recen, three layers are visible today in our part of Essex.

Erosion, erosion, erosion...


Sedimentary becs/sands

Upper Greensand

Gault

Shales & Mudstones

Geological Map of Essex

The other main factor in the shaping of our landscape has been the weathering, or erosion, of those rocks and sediments by rising and falling sea levels, by movements in ice sheets, by the action of rivers and by climatic forces.

The map of Essex, on the left, shows the visible geology as we see today. The area of White Colne is marked by a circle and the geology within it is shown in the legend and colour coded as in the cross section on the previous chart.

Two features to note are the spread of the glacial tills (pale blue) marking the southern extent of the ice sheet in the last Ice Age and the way the river systems stand out as many thousands of years of erosion have worn away the upper glacial layers (pale blue and pink) to reveal the underlying clay beds (brown).

Glacial Tills

Sand & Gravels

London Clay

Relevant Geology in White Colne

A river flows through it ...

The most visible natural impact on our environment has, of course, been the river Colne, from which we take our name. Since the Anglian Glaciation, almost half a million years ago, it has been inching its way through the layers of sands, gravels and clay. The result is a soft, gently rolling landscape typical of this area of North Essex and Suffolk.


The Colne is one of a number of rivers flowing eastwards to drain into the North Sea which have evolved since the Ice Ages.  Pre-glacial, the river system looked quite different, dominated by the Thames which flowed through where Chelmsford is today, just south of Colchester and north of Clacton. The ice sheet, which extended as far south as Hornchurch, pushed the Thames southwards to its present course, then retreated and left the landscape for the present river system to establish. But for the Anglian Glaciation, our environment would have been very much different.

This page gives a Brief History of the Geology of White Colne.


for a Detailed History please click here.

Sand & Gravels

Cross section through North Essex

    Years Ago              Period

The Geology of White Colne


Boulder clay/Glacial tills

Chalk

Sand & Gravels

Upper Greensand

Gault

Shales & Mudstones

London Clay

Sedimentary becs/sands

Anglian  Glaciation


Ice Age

 450,000


 2 million






 80 million







 100 million





 350 million






Pleistocene






Eocene



Palaeocene






Cretaceous




Silurian/Devonian

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