364 THE VERMILION IRON-BEARING DISTRICT. 



metamorphic effects upon the granite, they have not been observed, nor 

 have any dikes that conld be traced to the gabbro been found cutting 

 through it. 



INTERESTING LOCALITIES. 



The best portion of the area in the vicinity of Snowbank Lake in which 

 to study the relations of this granite to the adjacent sediments is east of the 

 lake, in general between its outlet and Disappointment Lake. In this area 

 the hills are bare, and good exposures are numerous. A number of good 

 exposures can be found on the shores of Snowbank Lake north and south 

 of its outlet, and here the Snowbank granite is found cutting the adjacent 

 conglomerates in numerous dikes. These same relationships ma}^ be found 

 still farther inland, on the hills in the area to which reference has already 

 been made. Other exposures showing the same relations may be found at 

 almost any place along the north and northwest shores of the lakes, and 

 a traverse inland from these shores will almost invariably result in the 

 findino- of dikes cutting the adjacent scliist. There is nothing especially 

 peculiar in the relations of these dikes to the rocks which they cut or in 

 the occurrence and appearance of these dikes, consequently no detailed 

 enumeration of them will be given. 



CACAQUABIC GRANITE. 



This granite occurs typically on the islands in and the shores of 

 Cacaquabic Lake, from which it was named by the Minnesota survey. It 

 has been ixiore or less extensively studied by the Minnesota State geologist 

 and his assistants, and mention and description of it occur in a number of 

 the State reports." 



U. S. G-rant has made an especially detailed study of this granite," and 

 as a result of his careful mineralogic and chemical analyses has determined 

 it as one of the comparatively rare augite-soda granites. Studies of the 

 Cacaquabic granite corroborate in the main the statements of Grant, but 

 there has been no opportunity to make detailed mineralogic studies or 

 chemical analyses of the rock, and data resulting from these have been 

 obtained from Grrant's articles, to which reference has been made. 



«Geol. and Nat. Hist. Survey of Minnesota, Fifteenth Ann. Eept, 1886, pp. 361-369; Sixteenth 

 Ann. Kept., 1887, pp. 149-156; Twentieth Ann. Kept., 1891, pp. 70-79; Twenty-first Ann. Kept., 1892, 

 pp. 5-59, 2 plates. Grant, U. S., Am. Geologist, Vol. XI, 1893, pp. 383-388; Geol. and Nat. Hist. 

 Survey of Minnesota, Final Rept., Vol. IV, 1899, pp. 294, 442, and 450; Final Kept., Vol. V, 1900, 

 descriptions of sections in various places. 



6Loc. cit. 



