Britain and Ireland: glacial landforms prior to the Last Glacial Maximum

The most extensive ice sheets over Britain and Ireland formed during the Middle Pleistocene in the Anglian Stage [Marine Isotope Stage (MIS) 12] and the Late Wolstonian Substage (MIS 6). The landforms and associated sediments are widely preserved in Southern England but are largely absent from the rest of Britain and Ireland because the last ice sheet covered these areas. Despite the restricted evidence, the Middle Pleistocene glaciations had a profound impact on the landscapes of Britain and Ireland. For example, Britain became an island for the first time in Anglian Stage and the Middle Pleistocene Ice Sheets essentially determined the modern drainage of Southern England. Early pre-Last Glacial Maximum glacier advance in the Devensian Stage [MIS 5d-2; Last Glacial Cycle (LGC)] is elusive but significant ice cover is indicated in the sedimentological and geomorphological records early in the LGC, in MIS 4 and 3, in several parts of both Britain and Ireland.