266 MESSRS. A. IIAKKER AND J. E. MAER OX 



17. The Shap Granfte, and the Associated Igneous and Meta- 

 MOEPHic Rocks. By Alfred Harker, Esq., M.A., F.G.S., and 

 J. E. Marr, Esq., M.A., Sec.G.S., Fellows of St. John's College, 

 Cambridge. (Read February 4, 1891). 



[Plates X., XI., & XII.] 



Page 



§ I. Introduction SOO 



II. Descuiption OF THE Granite 275 



III. The Dykes and Silf.s and their Relations to the 



Granite 285 



IV. METAMOlU'IlISiM OF THE SuKKOUNDING RoCKS : — 



A. The Andesitic Group 292 



B. The Rhyolitic Eoeks 301 



C. The Coniston Limestones 309 



D. The Silurian Rocks 317 



§ I. Introduction. 



Having been struck with the absence of any detailed description 

 of the metamorphism caused by the intrusion of a granite mass 

 into a complex group of volcanic products, we devoted ourselves to 

 an examination of the alteration produced by the well-known 

 intrusion of Shap FeU in Westmorland, being led thereto by a 

 knowledge that the volcanic rocks themselves presented a consider- 

 able diversity of characters, and that we should be to a certain 

 extent able to contrast the effects produced on the volcanic rocks 

 with those shown by fairly normal sedimentary rocks of various 

 kinds. Although the intrusive mass has been so frequently 

 noticed, and the literature on the subject is somewhat extensive, 

 very few authors have touched in detail upon the composition of 

 the granite and on the metamorphism of the surrounding rocks. 

 Indeed, the following papers are all to which we shall have to 

 refer with any frequency, and which we therefore, to save trouble, 

 cite at the outset : — 



Prof. H. A. Nicholson, " On the Granite of Shap in Westmoreland.'' 



Trans. Edin. Geol. Soc. vol. i. (1868) p. 183. 

 J. Clifton Ward, " On the Granitic, Granitoid, and Associated 



Metamorphic Rocks of the Lake District. — Part II. On the 



Eskdale and Shap Granites, with their Associated Metamorphic 



Rocks." Quart. Journ. Geol. Soc. vol. xxxi. (1875) p. 590. 

 Professors Harkness and Nicholson, " On the Strata and their 



Fossil Contents between the Borrowdale Series of the North 



of England and the Coniston Flags." Quart. Journ. Geol. Soc. 



vol. xxxiii. (1877) p. 461. 

 J. A. Phillips, " On Concretionary Patches and Fragments of 



other Rocks contained in Granite." Quart. Journ. Geol. Soc. 



vol. xxxvi. (1880) p. 1. 

 J. A. Phillips, "Additional Note on Certain Inclusions in Granites.*^ 



Quart. Journ. Geol. Soc. vol. xxxviii. (1882) p. 216. 



