Page:Quarterly Journal of the Geological Society of London, vol. 25.djvu/272

 3. Dividing ridge of Lower Carboniferous Rocks (see fig. 2).

I now come to the explanation which seems to me the most probable, and one which is borne out by an examination of the physical geology of the North of England, — namely, the existence of a concealed ridge, or barrier, of Lower Carboniferous rocks, dividing the hydrographical areas belonging to the Lancastrian and Salopian types respectively, and the consequent deposition of the contemporaneous beds in two separate basins.

In a recent communication to this Society* I have shown that at the close of the Carboniferous period the Carboniferous beds of Lancashire were thrown into a series of folds, the axes of which range nearly east and west, and are parallel to, and continuous with, those which influence the same beds in Yorkshire as they approach and are lost beneath the Magnesian Limestone, as originally pointed out by Professor Phillips. This system of disturbances I ventured to call " the Pendle System," because it is well illustrated by the direction and flexures of the Pendle range of hills, running in an east-north-east direction. I also showed that there was a nearly parallel line of upheaval to the south of this range, passing along the valley of Rossendale, the direction of which is very nearly east and west ; and to this I applied the term " Rossendale anticlinal."

When we proceed further south into the main coal-field of South Lancashire, we have no evidence of a repetition of these foldings (except, perhaps, as represented by a few east-and-west faults) ; but when, following the line of the Carboniferous rocks along the margin of the plain of Cheshire, we arrive in the district bordering the valley of the river Dane, near Congleton — we again have evidence of a very powerful line of upheaval lying to the northward of Congleton Edge, and dividing the Cheshire coal-field from that of North Staffordshire. The general arrangement of the beds here will be better understood from the accompanying section, in which minor details are omitted (see fig. 1). The section is drawn from north to south in a line nearly parallel to the " Red-

of the Carboniferous District of Lancashire and Yorkshire," Quart. Journ. Geol. Soc. vol. xxiv. p. 323.
 * " On the Relative Ages of the Lading Physical Features and Lines of Elevation