68 C. E. De Ranee — Mineral Veins in the North-west Country. 



are composed show a series of anticlinal and synclinal rolls, the 

 former generally corresponding to valleys and the latter to hills. 

 From the occurrence of patches of Permian here and there upon 

 the upturned and denuded edges of the strata of the Lancashire 

 coal-field, of sheets of Permian sandstone indiscriminately resting 

 on the Lower Carboniferous plains of Furness and the Vale of 

 Eden, on the denuded edges of the Coal-measures, Carboniferous 

 Limestone, and Lower Silurian strata in West Cumberland, it is 

 probable that north-western England had in many districts already 

 attained much of its present configuration in pre-Permian times, 

 with the all-important exception of the non-existence of the Pennine 

 chain ; though from my study of the Cross Fell district it appears 

 to me possible that the post-Permian Pennine fault coincides with 

 the line of an older unconformity and possibly a still older pre- 

 Permian fault, of the same general age as the Pendle curvatures. 



The movement of subsidence at the close of the deposition of the 

 Coal-measures was probably the means of producing " that exces- 

 sive lateral pressure by Avhich the older underlying strata were 

 squeezed and forced up into the series of sharp anticlinals forming 

 the axis of the Mendips and Ardennes," ^ and was the means of 

 " throwing the rock-masses into a series of great folds, ranging from 

 east to west, across North Lancashire and Yorkshire," * and of ex- 

 posing the strata, as it gradually sank beneath the level of the 

 breakers, to an enormous amount of marine denudation, which affected 

 not only the Carboniferous strata of the north-west of England, but 

 the Lower Silurian tracts of West Cumberland, where the Permian 

 strata rest transgressively on eroded Coal-measures, Mountain Lime- 

 stone, Skiddaw Slates, and "Greenslate and Porphyries." 



West Riding of Yorkshire. — One of the chief of these pre-Permian 

 axes in the Pendle district passes through Clitheroe, bringing up 

 the Mountain Limestone in that valley, as shown in fig. 1 of Prof. 

 Hull's paper,^ already so often alluded to, who also describes two 

 other anticlinals, the Sykes and the Slaidburn, named by Mr. 

 Tiddeman, of the Geological Survey, who surveyed them in detail. 



The former axis has the efiiect of bringing it also to the surface, in 

 the lower portion of the valleys of Sykes, Brennand, and Whitendale, 

 drained by brook-tributaries of the Hodder, and in all of which 

 are metalliferous lodes, which I have observed most minutely. 



At Sykes I found the strata to consist of Upper Yoredale Grit 

 (bottom beds), 240 feet. 2. " Whetstone Shales," with their siliceous 

 seams, 100 feet. 3. Black Shales, locally called " Great Ironstone 

 Shale," containing a band of black ferruginous compact cement- stone, 

 160 feet. 4. Thin fine-grained grit, locally " Trough House Kock," 

 30 feet. 4a. Black shale, " Trough House Black Shale," 20 feet. 

 4&. Thin flaggy grit, " Trough House Eag " (these beds are pro- 

 bably the Lower Yoredale Grit), 20 feet. 5. Black shales, with thick 



^ Mr. Prestwich, F. U.S., in Anniversary Address to the Geological Society, London, 

 1872, p. 65. 



2 Prof. Hull, F.R.S., Quart. Journ. Geol. Soc, 1868, p. 333. 



3 Op cit., p. 324. 



