Page:Quarterly Journal of the Geological Society of London, vol. 25.djvu/274

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along the course of the Yoredale beds to the north of the Cheadle coal-field, and across the Mountain-Limestone country by Meerbrook and Butterton, in the direction of Matlock, while a branch stretched more to the southward in the direction of Charnwood Forest.

I cannot, therefore, but regard the anticlinal fold which separates the coal-fields of North Staffordshire and Cheadle on the south from those of Poynton and Goldsitch Moss on the north as belonging to the Pendle system of disturbances, ranging nearly from west to east, and, by the position of the Permian beds at Rushton Spencer, clearly shown to have originated at the close of the Carboniferous period. If such be the case, can it be doubted that the anticlinal extends westward under the Triassic rocks of Cheshire ?

If, therefore, as appears to be the case, the Dane anticlinal stretches westward under the Triassic plain, we may reasonably look for some evidence of its continuance and reappearance on the western margin of the plain where the Carboniferous beds emerge from beneath the New Red Sandstone. This evidence, I think, we can find. The Carboniferous Anticlinal in North Wales. — If the Geological Map be referred to, it will be observed that at its southern extremity the Flintshire coal-field is completely dissevered from that of Denbighshire by the uprising of the Lower Carboniferous rocks, from which the coal-measures have been denuded.

The age of this fault, belonging probably to several periods of vertical movement, is, at least, clearly prae-Triassic, as it disappears beneath the New Red Sandstone near Hope without producing any displacement of the beds ; and it is also post- Carboniferous. Its relation to the Permian beds cannot be determined by observation, as it is nowhere brought into contact with them. It seems, indeed, to be gradually dying out towards the east as it approaches the New Red Sandstone, and to pass into an anticlinal axis. The view which I venture to offer is this : — I regard this upheaval as belonging to the Pendle system of disturbances at the close of the Carboniferous period, as indicated by the parallelism of its direction to this system, and also as being continuous in direction with the Dane anticlinal axis on the eastern borders of the Cheshire plain.

Supposed Structure of the Carboniferous Rocks under the Cheshire Plain. — If the above reasoning be admitted, it follows that there exists under the Triassic rocks of Cheshire an axis of elevation of Lower Carboniferous beds ranging from the southern borders of the Flintshire coal-field near Hope, on the west, to the valley of the Dane, north of Congleton, on the east, dividing the coal-field, which we may conclude originally spread uninterruptedly over the whole area, into two portions, to the north and south of this axis. I do not pretend to much precision in describing the course and structure of this axis under a tract of newer rocks 35 miles in width : it is probably accompanied by more than one parallel folding of the beds ; but I think, with the arrangement of the rocks at Congleton Edge and the Roaches near Leek before us, we might venture to idealize the structure of this axis and its relations to the newer formations