On the Norian or " Upper Laurentian" Formation. Vl*l 



Other observers believed, however, that the anorthosites 

 were eruptive, among whom were : Emmons, 1 Selwyn 2 and 

 Packard. 3 



None of the investigations on which these views rest were 

 either sufficieutly extended or sufficiently detailed to deter- 

 mine definitely the true relations of the two rock series, and 

 the question consequently remained undecided. On this 

 account I began in the summer 1883, at the request of Dr. 

 A. E. C. Selwyn, Director of the Geological Survey of 

 Canada, a detailed study of the anorthosite area, discovered 

 many years before by .Richardson, 4 about Lake St. John, and 

 the head watars of the Saguenay, and devoted the greater 

 part of two summers to investigating and mapping this 

 area. It proved, however, to be of much greater extent than 

 Eichardson supposed, extending back into the northern 

 forests through a tract of country unsurveyed and almost 

 unexplored, and which was for the most part only accessible 

 by rivers difficultly navigable and hard to ascend, so that a 

 very detailed investigation proved to be impossible. The 

 southern, eastern, and western limits of the area were, 

 however, mapped, and a good general knowledge of the 

 character and the stratigraphical relations of the area 

 obtained. 



It- was therefore thought beat to select a smaller area 

 more conveniently situated, in which to determine in de- 

 tail the stratigraphical relations of these rocks. For this 

 purpose the choice fell on that above mentioned as the 

 Morin area, which had the advantage of being generally 

 easy of access and which further commended itself as being 

 the area which Sir William Logan had formerly examined, 

 and on the study of which his opinion concerning the so- 

 called Upper Lauientian rocks were chiefly based. A care- 

 ful study of this area extending over four summers was 

 consequently made. 



1 Emmons, loc. ; cit. 



2 Selwyn, Rep. Geol. Survey Canada 1879-1880, 1877-1878. 



'■'• Packard, On the Glacial Phenomena of Labrador and Maine. Mem. Boston 

 Acad. Nat. Hist. Vol. 1., part 2, p. 214. 

 4 Richardson, Rep. Geol. Surv. Canada 1857, p. 71. 



