
- Clear-water Lake at Red-cliff Bay, where the same authority indi 
beds appear to be those represented south of the North-west Angle 
he COP ate BD 
, 
. 
. 









B. N. A. BOUNDARY COMMISSION. A ae 



4 
i 
- 
I have seen it. It may probably in this case cut the kami sh 






the existence of a considerable breadth of syenitic-greenstone and gre 
The direction thus indicated for the extension of the intrusive granite, 
appears to be further confirmed by the exceedingly even contour of the | 
shore as shown on the map, a feature which in other parts of the lake is sc 
found to arise from a parallel band of hard altered, or igneous rock ; a 
which, in this case, has maintained itself against the prevalent direst 
of glaciation. It would also agree with the general course of the mass — a 
where last seen to the eastward, and with that of the fold in the one f s: 
mentary rocks, which it appears to follow. The granite resembles we 
appearance that described as cutting ee typical Huronian and 
Laurentian rocks on Lake Huron.* 
101. Though the complicated structure of the rocks in the vicinity — 
of the Lake of the Woods, renders it impossible to give a detailed section E Be 
of the formations there exhibited; an approximate idea of their 
arrangement may be obtained. The Tiana formation appears tobe : 
represented, first, by a great thickness of granitoid and thick-bedded 
gneiss, generally pinkish or reddish in tint, and characterized by ortho- 
clase felspar. This passes upward into thin-bedded gneisses, and highly oe 
crystalline micaceous and hornblendic schists, often more or less epidotic. , ae 
The Huronian rocks are much more variable in character, but the lowest — os 



















granite, and are, for the most part, hard green rocks with little trace of = 
stratification, but hold some well stratified micaceous and chloritic schists, ; ao 
and also the imperfectly characterized gneiss already. referred to. — os 
($ 56-57.) On these rests a very great thickness of massive beds, 
characterized by the predominance of conglomerates, but also including 
quartzites, and compact dioritic rocks. Above these is an extensive 
series of schistose and slaty beds, generally more or less nacreous, and = 
chloritic or talcose ; but often hornblendic and micaceous. They include — ! 
also some conglomerate, quartzite, and diorite beds; but how often these 
recur, or on what horizons, it is as yet impossible to say. ; 








Lithological Character and Age of the so-called Huronian. i . 
102. The rocks spoken of throughout as Huronian, show coniiaet ia 
able resemblance to the typical series of that age, as described on 
Lakes Huron and Superior, but differ markedly in some points. They = | 


*Geology of Canada., p. 58. 
