Page:The South Staffordshire Coalfield - Joseph Beete Jukes - 1859.djvu/170

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SOUTH STAFFORDSHIRE.

It is, however, quite possible that the existence of the Rowley basalt and of the net work of dykes and veins of trap below it, was one of the reasons why the Dudley and Sedgley anticlinal was not continued to the south-south-east. The rocks beneath the basalt may be so bound and laced together by this net work of trappean braces, that the forces of elevation, whatever they were, were unequal to the task of bending them up into symmetrical curves and dome-shaped elevations like those of the Castle Hill and the Wren's Nest, &c., and left them, , therefore, comparatively undisturbed, except by fractures and dislocations, some of which we can trace, but of which many more probably exist than we are yet aware of.

I believe, therefore, that here, as elsewhere, wherever I have had an opportunity of making accurate observations, the mere intrusion or outburst of igneous rock has had little or no immediate connexion with the dislocations or elevations of the rock.

Following the direction of the line of the Russell's Hall fault south of Mucklow Hill, we find an interval of several miles in which no observations can be made.

What may be the position of the Coal-measures below the Permian beds of Frankley Hill we of course have no means of ascertaining; but on the south side of that ridge a few Coal-measures with a little coal showed themselves, on each side of the quartz range of the Lickey, in a nearly horizontal position. These beds may stretch continuously and horizontally under the Permian, from the valley south of Halesowen, and become exposed at the Lickey by simple denudation, in which case they are probably very high Coal-measures, or they may be the lowest Coal-measures brought up either by the rise of the beds or by dislocations concealed under Frankley Hill.

The Lickey Hill anticlinal.—If, however, we follow the direction of the southern half of the Russell's Hall fault, namely, about south-south-east, we shall strike in about 4 miles on the linear elevation of the Lickey quartz rock, which likewise has the character of a broken anticlinal. This fault, therefore, connects, if only in a vague way, the two anticlinal ridges of which the axes both run north-north-west and south-south-east, that, namely, of Sedgley and Dudley with that of the Lower Lickey.

The quartz rock of the Lickey is greatly broken and fractured, and in some cases violently contorted. At the northern end, about Holly and Rubury Hills, and by the New Road, it dips easterly at from 10° to 20°. Near the old Rose and Crown it dips west at 35°. In the quarry opposite the Reservoir it is violently contorted. At the south end limestone was formerly got, and there seem to be some softer shaly beds thereabout, which are doubtless the bottom beds of the Wenlock shale. It is believed that the eastern boundary of the quartz ridge south of the Colmers is a fault, with a downthrow to the east. North of the Colmers soft shaly beds, with calcareous bands and Silurian fossils, have been got on each side of the ridge, just underlying the Coal-measures.

We have doubtless here the very same beds that occur about Shustoke Lodge and near Hay Head, namely, the Llandovery sandstone locally altered into quartz rock and thrown into a small anticlinal ridge, with the bottom beds of the Wenlock shale and calcareous bands representing the Barr limestone covered unconformably by thin skirtings of Coal-measures. The Permian beds near Barr seem to be brought in solely by a fault, though perhaps even that is doubtful, while at the Lickey there is no occasion for any such supposition, since they seem simply to have covered up all the other rocks unconformably,