Abstract The Hampshire Basin was first characterized by Prestwich (1847a, b) as a tectonic/depositional feature (as the ‘Isle of Wight Basin ’). It is an east-west-orientated, broadly synclinal but asymmetrical structure, within which are smaller similarly orientated folds, preserving up to 800 m of Paleogene strata. It extends from southern England into the eastern English Channel (Figs 42, 135 & 136). It is limited in the south by the steep, en echelon monoclinal Purbeck 2 Isle of Wight folds. Upper Paleocene-lowest Oligocene strata are represented. Upper Eocene and Early Oligocene strata are preserved only in the northern half of the Isle of Wight and adjacent areas of SW Hampshire. The coastal cliff and foreshore exposures in the Hampshire Basin, particularly in the Isle of Wight, are the most extensive Paleogene sections in NW Europe, and have been studied since the late eighteenth century. Many other exposures and boreholes, including deep holes drilled for petroleum exploration, have contributed to the database. Recent remapping of large areas by the British Geological Survey (BGS), including several deep cored boreholes, has enabled a comprehensive revised stratigraphic framework for much of the succession (Edwards & Freshney 1987a, b; Insole & Daley 1985; Daley 1999; Daley & Balson 1999; King 2006).