i 
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B. N. A. BOUNDARY COMMISSION. 
been anna iiagn shia sich The i acne beds, however; north ¢ 
granite, shown in the general section, being quite local. A well-mar 
synclinal axis appears to lie immediately north of the Small Pro i 
montory, and to have a direction of east-north-east. There is also some 
evidence to show the existence of an anticlinal axis, which would st ‘ik a4 r 
the main shore about a mile south of Ka-ka-ke-wabec, and have a nearly — ‘a 
east and west course. From the attitudes of the rocks, and from the res oe. 
currence to the north of Lacrosse Island, of slate beds characterized i 
by small quantities of dolomite, and resembling those seen north of ae 2 
Ka-ka-ke-wabec, it is further probable, that another anticlinal axis is 
runs north-east through the former. Besides these, however, there ioe — 
be many folds not to be discovered without a minute topographical and zis 
geological study of the whole lake; and it is even possible that over- 
turned folds may occur without their existence being suspected. 
97. Two great series of movements seem to have conspired to give — 
form to the rocks of this region, both of which appear to have been post- 
huronian in date. The first of these apparently produced folds which = 
were not of a very abrupt character, but involved great breadths of strata; 
and which run in a general course a few degrees north of west. The great 
masses of intrusive granite are probably closely connected with this series — 
of disturbances, and are nearly parallel to the axes of the folds. These 
granites intersect indifferently rocks of Laurentian and Huronian age, and. 
are consequently post-eozoic. The Huronian rocks of the vicinity of the 
North-west Angle, are—as already fully stated—much altered by these 
granitic outbursts; and by the superior hardness due to this alteration, and 
possibly also the support of the granitic masses with which they are in 
contact, they have been able successfully to resist the subsequent violent 
north-north-east and north-east folding ;—flexure in these directions at the 
same time affecting the softer remaining portion of the Huronian, and 
bringing them up to a vertical position. These hardened rocks conse- 
quently now show comparatively moderate dips, and east and west strikes 
dependent on the previous disturbance. This arrangement will be clearly 
seen on an inspection of the smaller section, (Sect. 2) the nearly vertical 
rocks at the northern end of which, are the first of those which extend 
with similar attitudes to Rat Portage. ) 
98. The chain of large islands stretching northward from near Rainy __ Deh: 
River, though composed of Laurentian rocks only, is nearly parallel to = 

