Page:Transactions of the Geological Society, 1st series, vol. 4.djvu/121

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to have been derived from a subjacent rock of mica connected with the granite.


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Having described as far as I know the extent of the slate and greenstone, with the subordinate rocks and dykes that accompany them, I will now consider the strata by which they are encircled, and which on the east side are widely different from those on the west.

On the east side beneath the outcrop of the great limestone series of Cross Fell, (of which Mr. Winch gives the thickness at 450 fathoms,) the old red sandstone, in the form of a conglomerate, is regularly interposed between the lowest stratum of the above series and the slate, with no appearance of any great derangement. But on the west side of the line of greenstone there are evidences of disturbance, on a scale of considerable magnitude.

There is not a trace of those beds that are so regular on the east side, and appear there in such enormous thickness, and except in a few spots which will immediately be described, the red sandstone of the plain of Carlisle abuts abruptly against the greenstone and slate, [1] as it does also against the truncated extremities of the lower strata of the great limestone series [2] along the base of their escarpment on the north of Melmerby towards Brampton, and on the south of Murton towards Brough, beyond the north and south terminations of the slate and greenstone that have been described.

The village of Melmerby stands upon this red sandstone; a small stream that runs down to it (called Melmerby Beck), from the base of the great escarpment of the scar, has its course for three quarters of a mile above the village in the red sandstone, which here also

  1. See Section No. 1, Plate 5, letters A. B. C.
  2. Ibid. letters C. D. E.