The area south of London differs from the rest of lowland Britain in its generally east-west structural and relief trends. It has less extensive outcrops of Jurassic rocks, but much wider ones of Lower Cretaceous and Tertiary sands and clays. In addition, the finest development of chalk scenery is to be found here, for, not only does the Chalk outcrop over wide areas such as Salisbury Plain, but it is also less obscured by superficial deposits so that it exerts an immediate effect on landforms, soils and vegetation. The prevalence of minor folds causes the pattern of escarpments to be more complicated than it is to the north of London: in areas where these folds are pronounced, for example near Weymouth and in the western Weald, the escarpments are more intricate in plan than in areas such as the North Downs, where folds are far less prominent. Finally, unlike the rest of the lowlands, this region was not glaciated, although periglacial activity was responsible for some locally extensive developments of solifluxion deposits and to a certain, though arguable, degree for modification of landforms.
Although the threefold division of Great Britain used here has been made primarily for physical description, it may prove useful in the human geography of the land. The highland regions are areas of low population density, infertile soils and mainly pastoral farming; the upland regions include all the significant coalfields, apart from their concealed sections, and hence most of the major old industrial regions; the lowlands are the most fertile regions and the areas of the greatest uniformity of rural population spread.
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