Geography

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The landscape of Nene Park, like all landscapes is determined by the processes which have formed the earth over hundreds of millions of years.

All the layers of rocks found at or near the surface in this area are sedimentary rocks. Some were formed at the bottom of deep oceans and others under shallow tropical seas. Over time the land has tilted, sinking to the east and exposing up to ten distinct layers of sedimentary rock that can be seen within a 12 mile (20 Km) radius of Peterborough.

The rocks underlying this region are like a deck of cards spread across a table with the edges of each card showing at the surface. The older rocks are at the bottom of the deck can be seen in the west and the youngest at the top in the east.

A detailed description of the geology of the area can be found at R-I-G-S Peterborough Geology group.

Overlaying these processes are the effects of successive ice ages, the last of which ended in geological terms relatively recently, around ten thousand years ago. Ice sheets advanced and retreated as the world's climate changed, eroding and depositing material at different times. They may well have been the major influence on the landscape we see today.

During the last ice age at its maximum the southerly edge of the ice sheet probably reached some 50 miles (80km) north of where the present day Nene Park is. The land around here, immediately south of the ice sheet, would have experienced a climate similar to the high arctic zones of the world today. The ground would have been permanently frozen to great depth and covered in snow in winters. In spring, the melting snow and thaws at least on the surface would have created waterlogged ground, the run off would turn streams and rivers into raging torrents armed with chunks of ice that would scour away river banks.

As the ice age came to an end and the glacial ice slowly retreated north it released huge volumes of melt water and along with vast amounts of the materials scoured by and collected within the ice on its slow creep southwards over the millennia. This material would have consisted of anything from large boulders down to gravels, sands and clays that were left strewn across the then barren flood plane.

The River Nene would have been such a river, carrying with it millions of tons of material as it flowed towards the sea. This is the sand and gravel that was left in layers sometimes over 4m deep and under lays the land in most of the wider flat areas of the valley to the west of present A1260 Nene Parkway. At Thorpe Meadows, at the east end of the Park, a mixture of gravels, peat and clays under the soil suggests the beginning of the swamps which became the Fens and through which over thousands of years the river would meander on its way to the sea.

Since the ice retreated the land has in stages been uplifted, probably as a response to the disappearing weight of ice along with other factors. This effectively created a fall in sea level increasing the gradient of the river and accelerated erosion near the river mouth and causing the river to cut back upstream and forming a narrower deeper channel. The edges of the former flood plane were left high and dry as river terraces. Three different levels of terraces can be identified in Nene Park.

Eventually the fertile flood plane was cleared and settled by early farmers and over time a pattern was established of using the riverside meadows that were prone to periodic flooding for hay meadows followed by summer grazing with arable fields further back from the river on higher terraces stretching back to and up the valley sides. Where the valley sides were too steep to farm, they either remained as woodland or were planted as such.