..I.J 



A. WINVHELL — RESULTS <>!•' ARCHEAN STUDIES. 



Thia mass consists of hornblende gneisses, generally vertical, and Btriking 

 Dortheast. The orthoclase is reddish, and the individuals are mostly Large — 

 up to three fourths of an inch in diameter. Very rarely rauscovite is present, 



and not more frequently biotite. The nature of the rock in places bei les 



decidedly quartzose. A few pebbles of granulite and quartzite arc dissemi- 

 nated through it. This body <>f gneiss, or granitic gneiss, is everywhere 

 around t lit* Bhores of White Iron lake diversified l»v numerous inclusions of 



Ki'.rm. 1. — D G mitoid and Ghteisaoid Area \ ; -' 



mica and hornblende schist. This striking phenomenon 1 -hall refer to in 

 another connection.! 



The Saganaga Arm of granitoid rocks hold- Saganaga lake, with its long 

 southern arm-- centrally located, and lies in Minnesota on the fourth and 

 fifth rang* - of townships, stretching north five or six miles across the into 

 national boundary, where it i< limited by semi-crystalline BchistS. Toward 



the east-northeasl it extends into Canada an unknown distance, along a zone 

 north of Gunflinl and North lakes. This mass, as a whole, is distinctly a 

 quartz-bearing Byenitic gneiss. Ii is nowhere characteristically massive. 

 The quartz occurs throughout in Large angular individuals, attaining diame- 



• in default •■! ompany the prenenl memoir ii maybe useful to mention thai the 



.ill ink ---i in northeastern Mlnm onvenlently ihown on the map 



Facing p. 418) of the Name* »l la 



i untain l. ' ' Boutheaul ol I) to En i "< ir|. I. 



.nin-i L." toOgiehke-muncie lake— the namen employed In the Minn. 



n from the plate of the ' B i and Survey. A mor mplete map may be found 



Hi Ann. Rep of the Minneeota 8urvey 

 e White I • I in my report of IN . th Annu< 



