Geology Site Account

Site name: Colemans Farm Gravel Quarry

Grid reference: TL 834153

Brief description of site:

Colemans Farm Quarry is a working gravel quarry. The quarry works gravels and lacustrine (lake) deposits that are associated with two post-Anglian terraces of the River Blackwater. The site also exposes an unusually sandy form of the Lowestoft Till.

These gravels contain an interesting suite of rocks in the form of pebbles and cobbles which have been picked up by the river on its journey to the sea over hundreds of thousands of years. These rocks are not only locally-derived (e.g. blocks of the iron-cemented conglomerate known as ferricrete) but also 'exotic' rocks picked up from much older gravels (the Kesgrave Sands and Gravels) laid down by an early route of the Thames.

Several vertebrate fossils, such as mammoth teeth, and bones of other medium-sized mammals, have been recovered from the terrace gravels and from laminated deposits associated with the gravels. Flint artefacts have also been recovered. The age of these artefacts and fossils is unclear and research is ongoing.

The gravels in this area can provide important evidence of the evolution of the River Blackwater since the retreat of the Anglian Ice Sheet, 450,000 years ago.

Access to the quarry is only available with permission from the quarry operators.

Gravel at Colemans Farm Pit (photo R Mercer 2018)