Middle Pleistocene deposits at Stanground (Peterborough) and March, eastern England: A discussion based on new evidence

Middle Pleistocene deposits at Stanground and March comprise chalk-rich diamictons overlying deltaic deposits that infill depressions cut into the Jurassic bedrock. Both a fluvial and a glacial origin have been argued for the creation of the accommodation space occupied by the deltaic sediments. Although the deltaic sediments do not resolve the argument over the origin of the accommodation space, they do allow speculation that the sub-aqueous depositional environment required for deltaic sedimentation was formed by impoundment at The Wash of a pre-Anglian Fen Basin drainage-network. The evidence from Stanground, particularly, does not support sub- glacial creation of the accommodation space by ice moving from the north to east quadrant. These deposits demonstrate beyond doubt that low-lying areas existed (>18 m below present sea-level at March) in the area of the Fen Basin before the first- known major influx of Cretaceous material from the northeast.