HURONIAN FORMATIONS, TIMISKAMING REGION. 
7 
an angle of 50°. Also the foliation of the granite gneisses 
abuts almost at right angles against the line of contact at one 
place. The contact here, then, has all the characteristics of one 
of erosive unconformability. Upon the second island, instead 
of a clear line of contact between the conglomerate and the 
Basement Complex, there is an apparent gradation, the change 
occurring within 5 or 6 feet. Here the solid granite gneiss is 
first broken: then in passing upward the angular fragments 
have moved somewhat; in passing still farther upward they be- 
come roundish and are mingled with extraneous material, until 
a bowlder conglomerate is reached which is in every respect like 
that before described.^” 
This basal conglomerate is not of great thickness at any 
observed point in Bruce area and passes upward into 1,500 feet 
of white quartzite, portions of which carry thin conglomeratic 
beds of white and grey quartz pebbles. The quartzite is over- 
lain by about 60 feet of conglomerate and above this is 150 feet 
of impure, siliceous limestone. The lower and upper portions 
of the limestone consist of alternating limestone and sandy 
layers from f to 2 inches thick but the middle is less siliceous 
and the limestone layers are from 1 to 4 feet thick. In a few 
places the limestone is succeeded by a well stratified, schistose 
gre 3 rwacke. The contacts of this greywacke with the formations 
below and above it are soil-concealed everywhere in this area, 
but in Whiskey Lake area what is regarded as the same grey- 
wacke was found to be conformably upon the same limestone. 
The greywacke is the highest member of the lower Huronian 
series found in Bruce area. 
In lot 2, concession II of Aberdeen township, the limestone of 
the lower series, which dips 50 degrees southward, is overlain by a 
conglomerate carrying angular and rounded pieces of limestone 
and well rounded pebbles of granite, gneiss, etc. The contact 
is a slightly irregular one and the conglomerate rests upon the 
thick-bedded middle portion of the limestone formation, indi- 
cating that the upper, siliceous part had been eroded. At other 
places in the area this basal conglomerate of the upper series 
i'*The Pre-Cambrian Geology of North America”: U.S.G.S. Bull. 360, 
pp. 414-415. 
