RfiSUMfi OF LITERATURE. 1 1 1 



ceous slates and conglomerates. The schistose character is most full_y developed at 

 the contact with the granite. All evidence tends to show that the schists are due 

 to the intrusion of the granite, and suggests that the narrow belts of schist generally 

 found between the granite and the Keewatin rocks, and which have hitherto been 

 designated as a separate formation (Coutchiching or Vermilion) are only altered 

 portions of the Keewatin, which have been subjected to the heat and action of the 

 intrusive granite [p. 159]. 



The author also adduces further evidence to prove that, in accord with 

 Dr. Grant's statement to the same effect, the so-called Pewabic quartzite 

 between Birch and Grunflint lakes belongs in reality to the middle iron- 

 bearing member of the Animikie. (Cf abstract of Grant's report above.) 



1895. 



Smyth, H. L., and Finlat, J. Ralph. The geological structure of the western 

 part of the Vermilion range, Minnesota: Trans. Am. Inst. Min. Engineers, Vol. 

 XXV, 1895, pp. 595-61:5. 



Smyth and Finlay describe the western part of the Vermilion range. 

 The sedimentary rocks fall into two divisions. The older is a fragmental 

 slate formation, while the younger is an iron-bearing formation litholog- 

 ically identical with certain phases of the lower iron-bearing formation of 

 the Marquette district. To all appearances it is devoid of clastic material. 

 It is believed, from analogies with other iron-bearing districts of the Lake 

 Superior region, that the jasper of the Vermilion district is derived from a 

 cherty iron carbonate or from a glauconite greensand, or both. However, 

 as the jasper is a final product of the alterations, it is not possible to show 

 this. 



Intrusive igneous rocks are very abundant, cutting or being interleaved 

 with the sedimentary rocks in masses running from the thickness of a knife 

 blade to those 100 feet across. In quantity the igneous rocks exceed, 

 perhaps, several times the sedimentary rocks. The oldest igneous rocks 

 are greenstones. These vary from massive to schistose, and in some 

 places are what is called conglomerate breccias. The acid rocks were 

 intruded later than the basic rocks. They were originally for the most 

 part quartz-porphyries, but these have been extensively changed to sericite- 

 schists and conglomerate breccias and to rocks intermediate between these 

 and the original form. Within the larger masses of the igneous rocks, 



