The underlying geology of the parish is Sedimentary: to the South and East is of a Kellaways sand and siltstone.mix, and to the North and West a Kellaways clay deposit where the land rises at the western edge of the Parish. The whole is overlaid with Quaternary 'river terrace' sands and gravels dating back 1 or 2 million years. Unlike Tallington to the south, there has been no extraction of these deposits in Greatford. From the south west to the Northwest the west Glen river lies in a shallow valley, its floodplain formed of its own aluvium of clay and silt.