On the Uncomformability of the Permian Limestone to the Red Rocks West of its Escarpment in Central Yorkshire

(1) INTRODUCTION. Extending in a north and south direction, across nearly the whole of Yorkshire, are certain beds of Sandstone and Shales, which are frequently of a deep red or purple colour. They are generally found immediately below the Permian Limestone, but in some instances extend considerably westward from its escarpment. Large masses of it may be seen in the southern part of the county, locally known as the “Red Rock of Rotherham;” and further north, remarkable examples occur at Plumpton and Spofforth. The Red Shales may be studied at Conisborough, Pontefract, Barwiek-in-Elmete, and numerous other places. These Red Rocks have been described as New Red Sandstone, or the equivalents of the Rothe-todte-liegende of the Continental Geologists, from their resemblance to that formation as existing in Germany and Russia; they have also been considered as rocks of the Carboniferous formation, which, from their close proximity to the Limestone, have been transformed to a red colour by some chemical change, probably by the percolation of water-bearing Carbonate of Lime, or Carbonic Anhydride in solution, which on coming in contact with the Iron existing in the Sandstone or Shales, as a colourless protoxide, has been changed by the addition of oxygen to a peroxide, or red oxide of Iron, and may have caused the red colour of the rocks. This theory is borne out to some extent by the fact, that in many instances where the rocks have been traced to a greater depth, the red colour has been found to disappear, ...