London Basin

a low-lying plain in southeastern Great Britain along the lower course of the Thames River. It is a synclinal depression composed of Paleogene and Neocene clays, sands, and gravel. The basin lies between the Chiltern Hills to the north and North Downs to the south and is covered with brown forest soils. There are small oak and beech forests, and in sandy areas pine groves and heaths. The term “London basin” frequently denotes the cuesta plain between the Midland Plain to the north and the hills of North Downs to the south. The city of London is situated in the basin.