THE SOUTH-WESTERN PART OF THE COAL-FIELD.
Having described the line of division which separates the south-western from the central portion of the coal-field, let us now examine the lie of the rocks in that south-western portion.
It was shown in the last chapter that this was partly separated into two basins by the Netherton anticlinal.
The Netherton anticlinal.—A little east of the village called the Lye, near Stourbridge, is found a protruding mass of Ludlow shale, with a band of limestone like that before noticed at Turner's Hill and Sedgley. It dips east at 40°, but after running north of the road for almost a quarter of a mile, it suddenly ends, being probably cut off by a fault. Immediately south of the road it terminates somewhat in the same way.
In the cutting of the road the Silurian shale may be seen dipping east at 40° for about 30 yards above the limestone; there are then 9 yards of Coal-measure sandstone, with ironstone balls, dipping in the same way, and 100 yards east of that the bottom beds of the Thick coal may be seen dipping west at 65°, or towards the limestone. The Thick coal must, therefore, be reversed, or bottom upwards. In the Hays coal-pits, just east of this, the Thick coal is found greatly broken and disturbed, dipping generally east, at a high angle, and then suddenly assuming a nearly horizontal position, in which it continues some hundred yards to the eastward.[1]
From the Hays the crop of the Thick coal may be traced about a quarter of a mile to the south-south-west, when it curves suddenly to the west, dipping south at a considerable angle. On the other side of the Lye the Thick coal comes in again dipping west, and on this side the outcrop of the coal may be traced some distance to the south-west, when it appears suddenly to come to an end.
In the brook between these two terminations of the Thick coal some Coal-measures may be seen dipping to the south, it is, therefore, very probable that the apparent termination of the Thick coal outcrop te the south-west of the Lye is due merely to a sharp flexure and change in its strike, and that it turns suddenly to the eastward and joins that coming towards it from the other side of the anticlinal. The Netherton anticlinal will in this way terminate to the south with a regular sweep of the beds across the direction of its axis in the same way that it ends to the north.[2]
From the Lye to Netherton church the anticlinal runs very steadily to the N.N.E., the Thick coal dipping on either hand at an angle of about 20° to 25°, and its outcrop quite easily traceable by the old workings. Just north of Netherton church the anticlinal dies away, the two outcrops meet, and the Thick coal dips north till it flattens and rises again towards Dudley.
In the centre of this anticlinal, in the canal tunnel and cutting near Yew Tree Hill, is exposed a remarkable mass of basalt or greenstone
- ↑ I was informed that in one shaft the Thick coal was actually bent over near the outcrop, so that the same vertical pit passed twice through the Thick coal.
- ↑ Owing to imperfect and apparently erroneous information, a different direction was given in the first edition of the map to the outcrops of the coals at the south end of the Netherton anticlinal, and they were supposed to separate and spread till cut off by a fault. I owe the correction of this mistake to Mr. T. King Harrison of Stourbridge, and his ground bailiff. Mr. John Hatton. The same gentlemen also pointed out to me that the Thick coal of the little basin of the Grange (farther west), although it cropped up towards and into the boundary fault, never actually cropped at the surface, as I had been led to suppose when formerly surveying the ground.
