Page:VCH Leicestershire 1.djvu/31

 GEOLOGY ONE of the most striking features in the general geology of England is the fact that the outcrop of the geological formations forms a series of roughly parallel bands crossing the country in a south- west and north-east direction from the Channel to the North Sea. This regular succession of parallel bands is due to the general inclination of the strata to the south-east, but it is interrupted to a certain extent by two great anticlinal movements, one in the north and the other in the south-east, which have brought up lower strata and caused the outcrop of those above to divide into two arms, thus destroying the general symmetry of the arrange- ment. Where the two arms unite the breadth of the outcrop is much increased, and the widest spread of the covering formation occurs. The anticline in the south-east is that of the Weald, which ranges in an easterly and westerly direction, and has split the Upper Cretaceous rocks into two arms known as the North and South Downs. These unite to the west in Hampshire and Wiltshire, and form the great spread of Chalk country extending over the wide expanse of Salisbury Plain. The second anticline, which is the more important, and the one that affects the district with which we are now concerned, is the great range of the Pennine Hills, which runs from the borders of Scotland to the immediate neighbourhood of the county of Leicester. The main effect of this anticline is to separate the outcrop of the Trias into two branches, one of which extends north across the counties of Nottingham and York, while the other strikes to the north-west through Cheshire and Lancashire. At the bifurca- tion south of the Pennine Range the Trias attains its widest extension and produces the undulating country so characteristic of the Midlands. The county of Leicester, situated nearly in the centre of England, includes a large part of the great central plateau formed by the Trias and Lower Lias in this part of the country. The county in fact is nearly equally divided between these two formations, the western half being mainly covered by the Trias with small patches of older rocks protruding here and there, while the Lias occupies with a few exceptions the whole of the eastern half. It consists on the whole of a more or less undulating plain, which is over- spread in places with beds of clay and gravel. In the north-western part of the county this plain is broken by the elevated ground of Charnwood Forest, which rises in a somewhat miniature mountain range to the height of 9 1 2 ft., and forms the culminating point of the district, and the principal elevation in this part of the Midlands. To the west of this the Coal Measures are brought in, at first beneath a thick covering of Trias, but further west on the borders of South Derbyshire they come to the surface. On the eastern side some of the hills rise to a height of 600 ft., and are outliers of the great Oolitic escarpment which extends from the Cotteswold Hills to the H umber. This escarpment just enters the northern portion of the county, and forms the