12 
MUSEUM BULLETIN NO. 22, 
plates of marketable size. This granite mass, it may be repeated, 
has not been proven conclusively to be younger than the Huronian. 
The approximate distribution of these granites along 
the north shore is indicated in Figure 1. They show no 
tendency to become fine-grained at their contacts, and this 
together with the intensity with which they have contact- 
metamorphosed the adjacent sediments implies that they are 
masses of important size. The intruded sediments are steeply 
tilted, and are fractured and invaded by apophyses in much 
the same manner as are the rocks bordering the pre-Huronian 
batholiths. 
CONCLUSIONS. 
The Huronian formations along the coast of Lake Huron 
have been folded and faulted to a degree such as elsewhere in the 
Pre-Cambrian is usually ascribed to orotectic movements. 
Huronian formations deformed to this extent have not been 
found elsewhere in northeastern Ontario. 
Within this disturbed area there are granite masses of 
batholithic nature which intrude the Bruce series, and probably 
also the Cobalt series. No such granitic intrusives have hitherto 
been found in northeastern Ontario. 
The disturbance and granite invasion were both com- 
plete long before Ordovician time, for early Ordovician sediments 
lie horizontally upon a deeply eroded surface of the disturbed 
Pre-Cambrian. 
