In geology, the Bagshot Beds are a series of sands and clays of shallow-water origin, some being fresh-water, some marine. They belong to the upper Eocene formation of the London and Hampshire basins, in England and derive their name from Bagshot Heath in Surrey. They are also well developed in Hampshire, Berkshire and the Isle of Wight. The following divisions are generally accepted:Upper Bagshot Beds — Barton sand and Barton clay. Middle Bagshot Beds — Bracklesham Beds. Lower Bagshot Beds — Bournemouth Beds and Alum Bay Beds.