THE SHAP GKANITE AND ASSOCIATED «OCKS. 267 



J. J. H. Teall, "British Petrography" (188S), p. 322. 



Messrs. AvELiNE, Hughes, and Sxrahax, Mem. Ueol. Survey, "The 



Geology of the Country around Kendal, Sedbergh, Bowness, 



and Tebay," 2nd ed. (1888) p. 34. 



The granite forms an irregular oval, having a longer diameter 

 from E. to W. of a little under two miles, whilst its shorter 

 diameter in a N. and S. direction is somewhat more than a mile, 

 and the intrusion is situated very near to the boundary-line 

 between the Ordovician and Silurian rocks, both of which are 

 altered by it, and, as will be subsequently seen, its probable 

 apophyses penetrate upwards into rocks of Lower Ludlow age. On 

 the other hand, it was long ago pointed out that the poi-phyritic pink 

 felspars of the granite occur as fragments in the basal conglomerate 

 which underlies the Carboniferous Limestone. As they appear to 

 be somewhat limited therein, we may mention that they are seen 

 in vast profusion in a small clifE on the right bank of Wasdale Beck, 

 a few yards S.W. of Shap Wells Hotel, and near to where the 

 Carboniferous conglomerate rests upon the upturneji edges of the 

 Coniston Flags. The date of intrusion of the granite is therefore 

 definitely fixed as taking place after the deposition of the Lower 

 Ludlow rocks, and before that of the basal Carboniferous con- 

 glomerate, and it is usually assumed that the rock was intruded in 

 post-Silurian but pre-Carboniferous times, as is indeed highly 

 probable. The apophyses of the granite occur in a considerable 

 abundance to the south, as seen on the Geol. Survey map, and there 

 are a good number on the north side also. Besides this, there is a 

 network of irregular veins and branches along the immediate 

 margin, especially on the steep west face, which renders the deter- 

 mination of the actual boundary somewhat difficult, and indeed the 

 linear boundary of the map must be taken as drawn through the 

 points where the granite is not mixed up to any extent with 

 portions of the rock through which it has broken*. The general 

 shape of the intrusive mass will be discussed subsequently. 



The metamorphism produced by the granite is stated in the 

 Survey Memoir to extend to a distance of about a mile from the 

 margin. This appears to be the case, though we find that the 

 production of new materials is confined to a belt extending not 

 more than | mile from the contact. 



It is necessar)^ here to give some account of the trend, order of 

 succession, and lithological characters of the various rocks which 

 come within the influence of the granitic mass, and to describe a 

 section showing the succession of such rocks where they put on their 

 normal aspect away from the granite. 



The principal lithological varieties of the rock are exhibited upon 

 the map, but for our purpose a more minute subdivision than can 

 be laid down upon a small map is necessary, and we therefore 



* [We liave corrected the northern boundarj- of the granite on our map by 

 reference to the MS. six-inch map in the Geological Survey OfRce, to which 

 the Director-General has kindly allowed us access. — March 11th, 1891.] 



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