Peterborough landscape is formed
There has been a brick-making industry in Peterborough for over
a hundred years, but few people realise that the foundations of
that industry were laid down in the Jurassic Age, 150 million years
ago. At that time, most of the British Isles did not exist, and
many of the rocks we now see were being slowly deposited as
sediments at the bottom of sub-tropical seas. One of those rock
formations was the Oxford clay, formed from mud washed in from
surrounding land, which came to be used in the brick industry.
The seas swarmed with strange animals, including the coiled
ammonites so familiar to fossil-hunters today, huge marine reptiles
like plesiosaurs, ichthyosaurs and crocodiles, and fish. Sometimes
when these creatures died, their skeletons were preserved in the
mud at the bottom of the sea, to be buried deeper by later
sediments.
This process continued for 100 million years until enormous
earth movements squeezed up the ocean floor above the surface of
the sea. In southern Europe the Alps were formed, and in Britain
the ripples of those earth movements pushed the Oxford clay to the
surface.
Over the next 50 million years the forces of erosion laid bare
the ancient rocks that are now to be seen in the brick pits and
limestone quarries to the west of the city. Then, in the last few
hundred thousand years, a succession of ice sheets scraped off the
surface of the land. During the intervening warm periods, when the
ice sheets melted, huge quantities of sand and gravel were washed
out and left behind in the river valleys and fens.
These gravel deposits are quarried today for building
materials, bringing evidence of a landscape that is difficult to
imagine. Elephants, rhinoceros, bison, hippopotamus, reindeer and
wild oxen roamed, some in the ice tundra, others in the warm
inter-glacial periods, and their bones are often found in the
gravel pits, together with fragments of plants, fish, beetles,
snails and other small forms of life.
Our museum houses the skeleton of the 117,000 year old Deeping
elephant, several skulls of woolly rhinoceros and the skeleton of
the Whittlesey ox and also the best display of Jurassic marine
reptiles in Britain, outside of London.