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and as bands abruptly terminated and often broken and forming blocks
enclosed in the coarser gneiss, the blocks drawn out into long tails
along the planes of foliation.

At the head of the north-east bay, the contact between the gneisses Contact with
and the Keewatin crosses about half a mile from the extreme north
end. The granitoid gneisses are here seen in direct contact with
slaty, felspathic and quartzose schists of the Keewatin. The contact is
evidently an intrusive one as respects the granit^gneisses. A zone
of Keewatin schists is found to be invaded along its planes of lamina-
tion by long stringers or apophyses of granitoid gneiss and of a peg-
matitic mixture of coarsely crystalline quartz and felspar, or of almost
pure felspar, which also occurs in irregular masses cutting the Kee-
watin schists. The strike here is N. 64° E., and the dip about vertical.
Crowing from the head of this bay by a chain of small lakes and port-
ages leading easterly to Trout Lake^ the belt of Keewatin, which, as
has been already stated, attains on Lac des Mille Lacs, a width of
seven miles, is found to have disappeared.

About Trout Lake, typical granitoid gneisses, which extend across Trout Lake,
the height-of-land and down the south branch of the Savanne River,
are the only rocks exposed, with the exception of a very narrow band,
only ten to twenty chains in width, which occupies the ridge separat-
ing Trout Lake from Little Trout Lake. This seems to be an infolded
outlier of Keewatin enclosed by the gneisses similar to the one
occurring on Dog Lake. It is made up of felspathic quartzites with
slight schistose structure and granitoid, quartzo-felspathic, massive
rocks, intimately mixed with granites and gneisses belonging to the
gneissic complex, which are here intermingled in great confusion with
the Keewatin schists.

Savanne Lake,

Savuuie Lake is reached from Trout Lake by way of two small Savanne
lakes and a portage of a mile and three-quarters ; Laurentian granitoid ^'



\ are seen in the vicinity of this lake. They vary from fairly
coarse red gneisses to fine black biotite gneisses, which apparently



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48 H WESTERN ONTARIO.

hold some hornblende. Down the south branch of the Savanne River
no exposures were seen, the river flowing through low swampy land.
Ridges rising from the muskeg are composed of boulders of gneiss only.
The disappearance of the Keewatin belt here is also proved by the
section afforded by the Canadian Pacific Railway, where, with the poa-
sible exception of a few exposures of hornblende-schist about two miles
south of Woodland, that may represent infolded Keewatin rocks,
no exposures other than Laurentian are seen from west of Upsala
down to about a mile south of Buda, where the northern edge of the
southern Keewatin area crosses the railway.

Muskeg Lcike,

Muskeg Lake. Muskeg Lake lies entirely in granite-gneiss, generally coarse and
but obscurely foliated and in places showing large crystals of felspar
an inch or more in diameter.

Part of the shores of the lake and some of the islands are drift-
covered, the banks of sand rising in places on the east shore to a
height of more than thirty feet Some of the islands are cultivated
by the Indians who grow good crops of potatoes. The land about the
lake is nowhere high, and in some places broad areas of musk^ are
separated from the lake only by a barrier of sand and gravel heaped
up by the ice and waves.

Beaver Lake,

Beaver Lake. A very interesting series of rocks is exposed about this lake, which
lies in a basin excavated in an arm of granite that extends south-
ward from the main granite-gneiss area into the diorites and schists of
the Seine River Keewatin belt.

Ck>nutct of Contacts of the two series of rocks are frequent on both sides of the

^dTdionte.^^ lake, showing the granite-gneiss invading the diorite in long arms and,
in places, the gneiss invaded in a similar way by diorite. Although
the general form of this granitic arm would indicate that it is intrusive
in the diorite, the details of the contacts seen in many points about
the lake show that both rocks have been in a viscid or liquid condition
and that each has invaded the other, producing a contact zone where
the relations are most complex. Faults have also affected the rocks
here and have helped to obscure their relations. One of these which
Dioritic shows considerable displacement, can be seen on the west side of the

lake, where the line of faulting seen on a small island, is indicated by
a breccia made up of semi-angular to well-rounded boulders and



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1.J HAWK LAKE ROUTE. 49 H

pebbles of diorite and gneiss some of which are as much as two feet in
diameter, contained in a matrix of rotted rock charged with pyrite
and chalcopyrite. The inclosed blocks as well as the cementing
materials are all dioritic on the diorite side and all granitic on the
granite side of the belt. The line of fault continued to the main west
shore, is seen there to be marked by a wide vein of white quartz.
The conditions seen in these contacts seem to indicate that the
present form of these rocks has been induced long after the first solidi-
fication of both, probably by pressure exerted when they were deeply
buried under overlying strata which have been since denuded.

Niven Lake,

This lake, which lies two miles to the east of Nonwatin Lake, has an Niven Lake,
extreme length of five miles and is nowhere more than three-quarters
of a mile in width, with a very irregular shore-line. The whole of the
eastern end is occupied by diorites and schbts of Keewatin age, except-
ing a few hundred yards of the south shore, where an isolated area of
granite cuts the schists. The western part of the lake lies in the gneiss
area which is here made up of homblonde-granite-gneisses and biotite-
gneisses, becoming, close to the contact, crystalline felsites and diorites,
which invade the diorites and hornblende-schists of the Keewatin,
sending out into them long arms and vein-like stringers.

Hawk Lake Route,

The route from Hawk Lake to Old Man Lake gives another section Hawk Lake to
through this Keewatin belt, which has a width, where the route Lak©.
crosses it, of about six miles, extending from Pyramid Lake to Old
Man Lake. Southward from the Canadian Pacific Railway, through
Hawk Lake and the stream and lakes emptying into it from the south,
and all about Pyramid Lake, biotite-granite-gneisses are seen, usually
well foliated, and striking east-and west. Across the Keewatin belt Section.
the exposures are infrequent, the route, for the greater part of the
distance, following winding streams in flat marshy land. At the foot
of Pyramid Lake, on two small lakes tributary to Brush Creek, about
half way between Pyramid and Old Man lakes and along the northern
and eastern shores of the last-named lake, the rock exposures that
serve to define the belt,* occur. They consist of chloritic and hom-
blendic green schists and occasional exposures of massive diorite. The
general strike is parallel to the trend of the belt, about east-and- west.
The quartz-schists and altered quartz-porphyries, which occur in con-
4



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?



50 H WBSTERN ONl'ARIO.

siderable strength further west on the belt, seem to be wanting here, or,
at least, they were not observed.

Seine Lake to A route extending northwards from Seine Lake through Caribou
^' and a number of smaller lakes to Scotch Lake and the Canadian Pac-
fie Railway, gives a section across the measures of this Keewatin band
to a point intermediate between Clearwater Lake and Brush Creek.
Rocks met The hornblende-gneiss division occupies the first half-mile along the
section. shores of Seine Lake, the rocks consisting of greenish-white gneiss,

highly quartzose, contAining films of a green chloritic mineral, asso-
ciated with dark quartz-diorite with a large proportion of hornblende.
Biotite is not entirely absent, and in places the gneisses are biotite-
gneisses. The boundary between the two has been placed so as to include
on one side those rocks in which the biotite predominates and on the
other those which shew the greater proportion of hornblende. North-
wards along Seine Lake, typical biotite-gneisses strike pretty uniformly
S. Sb" E., with, however, much local twisting, particularly where, as
is frequently seen along the lake, coarse pegmatite* like white gneiss
invades the finer black gneiss, both in the form of irregular masses
and sheets and as long arms, often enclosing angular blocks of the fine
black biotite-gueiss. These gneisses continue fairly uniform in
character to a point about half a mile beyond the first
little lake north of Caribou Lake, where the hornblende gneiss
division is again seen, the rocks as before consisting of
syenites or quartz-diorites and a gneiss which contains both
Keewatin belt biotite and a green chloritic mineral. The belt of Keewatin
L^estoticn. ^cks that extends eastwards to Hawk Lake station and west-
wards to join the Seine River band, adjoins these rocks on the
north. The belt has a width, where the route crosses it, of a little
over three miles and three-quarters, and consists in the main of diorites
and diabases with green hornblendic and chloritic schists which prob-
ably represent crushed forms of these rocks. A narrow fringe along
the southern edge of the belt, is made up of quartz-porphyries in various
degrees of alteration to the extreme of a regular sericite-schist with
blebs of slightly opalescent to clear quartz. Rocks of the same char-
acter are occasionally met cutting the schists throughout the band,
where crushed into a schist conforming in strike to the trend of the
enclosing rocks. Along the northern border of the belt occur felspathic
schists and quartz-schists with hard bands of schistose conglomerate, the
pebbles of quartz and quartzite. Some of the schists exposed along
the south shore of Norway Lake weather very rotten and rusty from
the decomposition of thin sheets of iron-pyrites scattered through
them.



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■■**^] GLACIAL GEOLOOT. 51 H

Adjoining this belt on the north is an area of non-foliated biotite Granite and
granite, which, near the contact with the diorites, becomes hornblendic, §*b!dt^"*^
but which is, in the exposures which are plentifully seen about the
lake, a coarse red granite of quartz, orthoclase and biotite. To the
northwards the granite gradually assumes a foliated character, until
on Lower Scotch Lake it becomes an ordinary, well-foliated, biotite-
gneiss with, however, in certain layers, a small proportion of horn-
blende. The strikes vary considerably along the lake-shore, shewing
considerable folding of the strata.

Glacial Geology.

The evidences of glacial action over the whole area under considera- I>irection of

glacial stnse.
tion are very plain, everywhere in the form of well marked glacial

strite and grooving and in places as morainic accumulations of glacial
drift. The direction of ice-movement was remarkably uniform. From
the Kaministiquia River westward the striae follow a direction about
25' west of south, gradually becoming more westerly in their trend
until in the Rainy Lake country, as reported by Lawson,* their aver-
age course is about S. 40' W. North of Rainy Lake, between it and
the railway, the course is about S. 30' W., and about the shores of
the Lake of the Woods, S. 45' W. There are of course local devia-
tions from the general direction, particularly where the trend of a
lake- or river- valley makes a moderate angle with ^he general course.
East of the Kaministiquia River there was a swing in the ice-move-
ment towards Thunder Bay, as striae along the Dawson road shew a
direction 30' east of south. A few striae in this eastern region seem
to belong to the later set which is so prominent about Lake Nepigon
and its neighbourhood. Their direction is about west.f

Well marked morainic ridges are found at various points through- Morainic

ridflTBs
oat this section along the Canadian Pacific Railway near Nordland.

High ridges which lie to the north of the railway track are without

doubt of this character. The ridges are generally composed of rolled

boulders and sand, and extend for some distance approximately parallel

with the track with a steep face towards it.

At the north-east end of Drift Lake a very beautiful example of a Kame-like
kame-like ridge comes down to the lake-shore. It is composed of
rounded boulders of gneiss of varying size, with coarse sand composed
of granitic debris filling the interspaces. Its course from the lake-

* Anniial Report GeoL Snrv. Can., 1887-88, voL III. (N.S.) Part F.
t Report of Pmgren, GeoL Surv. Can. 1866-69; also Summary Report, Geol.
Sorv. Can.. 1874.



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52 H



WESTERN ONTARIO.



Morainic
accumula-
tions.



shore is north-north east over a sandy flat from which it rises as a
sharp ridge, from one chain to three yards wide at the top. At
twenty-five chains back from the shore it widens out and merges into
the general level of the country. On the portage leading south frpm
the south end of Greenwater Lake toward Hoof Lake, a striking ridge
of the same character is followed by the portage for seven chains. Xt
is composed of sandy loam filled with well-rounded boulders of gneiss,
diorite and various schists, and crosses a valley from side to side in a
direction five degrees west of south, rising seventy-five feet above the
valley. The top is merely wide enough for the trail, and the sides slope at
the angle naturally assumed by the material.

Irregular morainic accumulations occur at a number of difiereat
points, notably over the region lying north of the valley between Nord.
land and Linkoing. This part of the surface is generally deeply drift-
covered and shows irregular ridges and numerous cirque-like hollows
about one hundred feet in depth and a little more in diameter at the
top. The basins are generally dry, draining freely through the loose
drift, but one was observed close to Prairie portage which held a small
lake. Cold water Brook which gushes out as a good sized stream from
the base of the drift ridges, doubtless derives its water from the drain-
age of these basins. The water is quite clear and extremely cold. The
temperature, ascertained by S. J. Dawson's exploring expedition in
1858 was 4r-5 Fahr.



Area of red
cla3rs.



Various

stratified

deposits.



Lacustrine Clays and Sands,

The basin, occupied by surface deposits of red clay and sand,
extending westwards from Kaministiquia station on the Canadian
Pacific Railway to within four miles of Nordland station, is bounded
closely by the 1450 foot contour-line. It thus evidently forms an
independent local lake-basin, cut off entirely from the Wabigoon basin
further west by the higher land which forms the east-and-west water-
shed. Crossing Pigeon River at about twenty miles from its mouth,
and Whitefish, Matawin and Shebandowan rivers at about the same
distance from the Kaministiquia, this 1450 foot contour includes
Dog Lake and the valley of Dog River nearly to its head with
lower land extending eastward to Lake Superior. Morainic ridges of
drift bounding the basin on the north, are probably terminal moraines
accumulated at the foot of the glacier at the stage of its recession
during which the lake had existed.

Stratified deposits of sand and gravel are found on Lac des Mille
Lacs, Shebandowan and other lakes, at levels which vary too much to



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HdNNCs] GLACIAL STBLE. 53 H

allow of their having been formed in one lake basin. The proba-
bility seems to be, rather, that small, local lakes were formed from
time to time, whenever the climatic conditions were such as to cause
a pause in the receding movement of the ice-front, forming ice-barriers
bounding the northern shores of lakes of which other parts of the
shore-line were formed of accumulations of glacial drift.



Glacial Strice,

Red River Road, 6 miles from Thunder Bay W. Glacial

104 M „ H S. 80" E. striae.

13 u .. ., S. 30" K

Dog Tjake, south-east end S. 26" E.

S.E. shore between East Bay and S.E . end S. 4o E.

N. of last.... S. 6" W.

western end of East Bay S. 20" W.

East Bay near east end S. 36" W.

It II midway on north shore S. 26" W.

II midway on west shore S. 14° E.

2 miles north of S.W. end S. 24" W.

outlet S. 10" W. to S. 11" W.

Matawin River, below Browns Lake S. 8" W.

II II 3 miles above junction with Shebandowan

River S. 6" W.

Shebandowan River, 1 mile below lake S. 6" W.

Similes .. ., S. 6" W.

Shebandowan Lake, 3^ miles west of outlet S. 2" W.

4 '• " s. ir W.

6 11 11 S. 22" W.

II west end of Lower Lake S. 23" W.

It 1. near Beaver-house Hill S. 31" W.

Mud Lake, east end S. 22" W.

Peewatai Lake, near outlet S. 24" W.

Greenwater Lake, 1 mile S.E. of Shelter Island S. 26" W.

Lao des Mille Lacs, at height-oMand portage S. 24° W.

II II first point north of portage S. 20" W.

I. 11 island north of Bolton Bay S. 10" W.

II II island opposite Poplar Point S. 19" W.

II II large island west of Pine Point S. 11° W.

Baril Bay S. 4<» W.

Broad Point S. 4" W.

north of BuJlIsland S. 6" W.

Canadian Pacific Railway, 1 mile west of Matawin River S. 2P W.

Canadian Pacific Railway, 1 mile west of Matawin River

occasional heavier striae S, 4" E.

Canadian Pacific Railway, 2 miles west of Upaala S.

Round Lake, near Moss Tp. line, down steeply sloping surfaces S. 11" W.

Huronian Road, 3 miles north of Loon Lake S. 5^ "E.

Round Lake, near district boundary S. 20" W.

Crooked Pine Lake, east end S. 24" W.

•1 II 3 miles from west end S. 21° W.



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54 H WESTERN ONTARIO.

Glacial striae- Crooked Fine Lake, midway on south shore S. 19** W.

<^onL „ „ westend S. 2^ W.

Sabawy Lake, south shore a 26" W.

.. M west of last S. 30" W.

Partridge Lake, S. W. end S. 27" W.

Sawbill Lake S. 16" W. to S. 24" W.

Clearwater Lake S. 6» W.

Six miles north of Clsarwater Lake S. 16" W.

Eye River, west of Right-eye Lake. S. 16«» E.

Sturgeon Lake, north end S.

Seine River, 4 miles N.B. of Island Falls S. 10" W.

,. north end Reserve Island S. 24" W.

.1 west shore Moose Lake S. 20 W. to S. 26" W.

II Steep Rock Lake, S.K bay, on steeply sloping

surface S. 16» E.

M Steep Rock Lake, island near centre . S. 16*> W.

East end of Perch Lake. S. 6" W.

South shore of Perch Lake S. 2" K

North I. H S. 16" W.

North M I S. r W.

., elbow west of Cahn Lake. S. 26" W.

7th portage above Sturgeon Fall S. 26' W.

4th .. S. 32" W.

Lake just south of Jackfish Lake S. 15" E.

Pine Lake. S.

Atikokan River, north of Trout Lake S. 20" W.

Quotico River, 8 miles below Beaver-house Lake. .S. to W. to S. 7" W.

Whitefish Lake, East shore S. 82«> W.

north shore S. 23" W.

west shore S. 26" W.

Atikokan River, 1 mile west of Sabawy Lake S. 19o W.

Lac des Isles, south end S. 34" W.

north end S. 41" W.

Pipestone River, below Pipe Lake S. 14" W.

Crow Rock Lake, S. W. Bay S. 2" W.

Clearwater Lake West, N. E. shore S. 4" W.

Lower Scotch Lake S. T W.

Fox Lake S. 8" W.

Pickerel Lake, 1 mile east of Pine Portage (2 sets.) S. 40" W. to S. 67" W.

Batchewaung Lake, island in main lake S. 8" W.

Quetico Lake, N. shore of main lake S. 8" W.

Economic Geology.

Iron,

Iron ores. Iron ores are widely distributed throughout the Keewatin belts of

the region dealt with in this Report. In the Matawin and Atitokan
iron ranges extensive deposits of high-grade ore have been discovered,
and their extent has been proved in some measure, by cross-trenching,
test-pits, etc., and by the use of the diamond drill.



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•"a*""-] ATIKOKAN IRON BBLT. 55 H

In the Matawin field the ores consist both of magnetite and haematite.
Where they are exposed at the surface the ores are interbanded with
chert and jasper, but exploitation by diamond drill has revealed, it is
stated, large deposits of clean ore.

Atikokan Iron Belt.

On the Atikokan River, the iron-bearinff belt is continuous for a Iron oree of

Atikokan
long distance, showing at intervals good deposits of ore. The cleanest belt.

and best deposits occur near the eastern end of the belt, diminishing
in amount and increasing in impurity as the band is followed west-
wards. The best surface showing is seen at the McKellar locations, McKellar
between Magnetic and Sabawy lakes. The ore here occurs in a ^<^^**'^°»-
Uuff which rises boldly from the right bank of the river at a distance
of about three hundred yards back from the shore. A section across
the iron- bearing band between lots 10 E. and HE. gave approximately
the following thicknesses for the belts of magnetite, though the strip-
ping at the time of my visit was not sufficient to afiford a quite satis-
foctory section. From the face of the bluff thirty-six feet of clean ore
is exposed, followed, further north by two other bands, one twenty-seven
feet wide of interbanded clear and impure ore and another of unknown
thickness, the intervening bands of country-rock having a thickness of
about thirty feet. The bands can be traced along the bluff for over
four hundred yards and occur as overlapping lenses of ore, which may
die out as far as one particular lens is concerned, but is continued in
recurring lenticular masses. The ore is a very good magnetite, show-
ing a little pyrite and copper-staining in places but generally free from
impurities. Dr. Hoffmann reports that an analysis of a specimen from
the line between locations 10 E. and IT E. was made by Mr. Johnston,
with the following result* :

Metallic iron 66*71 per cent.

Titanic acid None.

The inclosing rock is a diorite with a large proportion of hornblende. Wiley
Below Sabawy Lake, at the Wiley locations R. 400 and R. 401. At >«»*i«^
the time of my visit the trenches which, when made, must have
given a good section across the belt, were partly filled in, so that the
section seen was not a perfect one. The mode of occurrence of the
ores here and their general character, are similar to those above
referred to. The inclosing rock is also quite similar. Three beds of
ore are here exposed, the most southerly about thirty-nine feet in width,

♦ Annual Report, Geol. Surv. Can., vol. V. (N.S.) 1890-91, p. 38r.



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66 H



WE8TBRX ONTARIO.



Analyses.



Locations
further down
the river.



made up of clean rich magnetite with only one narrow band of the
country-rock. Two other bands of ore, with an intervening belt of
country-rock occur to the north ; the centre one of the same rich ore
and the northern one of banded lean ore with a richer bed less than
three feet in width. There is here an excellent showing of good ore
extending along the ridge for about five hundred yards. A little
pyrite occurs here and there. Dr. HofEmann reports the following
results, of analyses of specimens from the locality made by Mr. John-
ston.*

Magnetite from location 400 R.

A massive magnetite.

Metallic ron 68-03 per cent

Titanic acid none.

Magnetite from location 402 R.
Massive, fine-granular magnetite.

Metallic iron ^ 6803 per cent

Titanic acid None.

Magnetite from location 403 R.

A fine-granular magnetite.

Metallic iron 64*56 per cent

Titanic acid None.

Magnetite, from two miles and a half west of Sabawy Laka
A massive magnetite.

Metallic iron . 67'42 per cent.

Titanic acid None.

Further down the river, at the second location, known as the Pat-
terson location, the ore is well exposed in two rich bands of about
thirty-five and twenty feet respectively. The ore-bands are here ex-
ceedingly rotted at the surface and probably hold much pyrite.

Still further down the river, at location 138 X, quite as broad a
band of iron-ore bearing strata occurs. The ore is magnetite, but is
very much interbanded and mixed with country-rock, only four or five
feet of continuous, clean ore being noticed in the surface exposures.

At the Garland location, below Steep Rock Lake, the iron-bearing
belt is exceedingly crumpled and folded, and it is very hard to arrive
at the thickness of the ore-beds. At the top of an anticlinal fold, two
feet of good clean ore occurs, with about sixty feet of interbanded ore

• Annual Report, GeoL Surv. Can., vol. V. (N.3.) 1890-91 p. 38 r.



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.] MATAWIN IBON BELT. 57 H

and country-rock. A good deal of pyrite was noticed associated with
this ore. The band has been affected not only by abrupt and
complicated folding, but apparently also by faults.



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