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GEO

LOGY LIBRARY

LIBRARY OF
WELLESLEY COLLEGE

PRESENTED BY
Mary J. Lanier

GUIDE BOOK: No. 7

EXCURSIONS

Sudbury, Cobalt and Porcupine

(EXCURSIONS A 3 and^C 6)

ISSUED BY THE ONTARIO BUREAU OF MINES,
TORONTO

TORONTO:

Printed by L. K. CAMERON, Printer to the King's Most Excellent Majesty

1913

19ft

A. J 3 3<?A
GEOLOGY LIBRARY

l_8S
IS

7-2

GUIDE BOOK No. 7

Excursions to Sudbury, Cobalt
and Porcupine

CONTEXTS.

PAGE

Preface 5

The Sudbury Area 10

by A. P. Coleman.

The Cobalt Area 51

by Willet G. Miller.

The Porcupine Area 109

by A. G. Burrows.

Temagami 139

by Willet G. Miller.

List of Illustrations 149

PREFACE.

The three mining areas, viz. : Sudbury, Cobalt, and Porcu-
pine, that are described in this Guide Book, are the most
important in the Province of Ontario. Sudbury is the
world's greatest producer of nickel and is also an important
producer of copper. Minor quantities of platinum, palla-
dium and other metals have been obtained from its ores.
Cobalt leads all other areas in the world in its output of
silver and of cobalt, and arsenic and nickel occur in import-
ant quantities in its ores. Porcupine, the product of
which is gold, is a comparatively new mining area and
is only partly developed. The two chief mines, however,
are splendidly equipped, and during the last year have been
important producers. Other mines at Porcupine have re-
cently begun milling operations.

As nearly as can be determined from Government reports,
Sudbury had produced, in round numbers, 158,000 tons of
nickel and 103,000 tons of copper by the end of 1912.
Statistics of by-products — platinum, palladium, and other
metals — are incomplete. At the same date, cobalt had pro-
duced approximately 156,000,000 ounces of silver. In 1912,
owing to the Porcupine production, the gold output of
Ontario had a value of $1,859,285, compared with $42,637
in 1911.

The ore deposits of all three of the areas are in rocks that
are classified as of pre-Cambrian age, and are believed to
owe their origin to igneous intrusions. At Sudbury the
intrusive rock, described on following pages, is quartz-
norite, at Cobalt quartz-diabase, and at Porcupine granite.

Sudbury is about 90 miles to the southwest of Cobalt, and
it is believed that the norite of the one area and the quartz-
diabase of the other are genetically connected. The close
chemical relations of the two rocks are described in the
following pages devoted to the Cobalt area.

The colored geological map, on a scale of eight miles to
the inch, that accompanies this guide book, shows the
geology of the three areas in so far as it is at present
known. Larger scale maps have been published and are
referred to in the text.

Relations oe the Rocks.

Keewatin Series.

As the legend on the map shows, the oldest series known
in the region is called the Keewatin. It consists for the
greater part of basic volcanic rocks, now represented by
schists and greenstones, together with more acid varieties
such as quartz-porphyry. Associated with the Keewatin is
considerable sedimentary material, consisting of schistose
greywacke, jaspilyte, or iron formation, and crystalline lime-
stone, which is, however, not seen in large exposures in any
of the three mining areas. These sedimentary rocks are
believed to represent the Grenville series of southeastern
Ontario.

Laurentian Granite and Gneiss.

The rocks next younger than the Keewatin are grey gran-
ite and gneiss. They are well exposed along the railway
north of North Bay, and are called Laurentian.

Temiskaniing Series.

After the intrusion of the Laurentian into the Keewatin,
there was a prolonged period of erosion, during which a
thick series of sediments consisting of conglomerate, grey-
wacke and other rocks was deposited. To this series in the
Cobalt and Porcupine areas the name Temiskaming has
been given. It is known in other areas to the north, south
and west of Cobalt and appears to be represented at
Sudbury by what Dr. Coleman has called the Sudbury
series.

Lorrain Granite.

After the deposition of the Temiskaming sediments an
intrusion of granite, characteristically pink in color, took
place. This granite, which occupies large areas, is known
as Lorrain. The relations of this granite to both the older
and younger rocks are clearly shown at Cobalt. The granite
which gave rise to the gold deposits at Porcupine appears
to be of the same age.

Cobalt Series.

The period of erosion that succeeded the intrusion of the
Lorrain granite gave rise to the conglomerate and other
rocks known as the Cobalt series. Good exposures of these
rocks are to be seen at Cobalt and along the railway to the
south and to the north. At Porcupine only small exposures
are found. The Ramsay Lake conglomerate of Sudbury
appears to be of the same age.

In the Sudbury area there is also a series of sediments
which has been mapped as of Animikie age. The age
relation of this series to the Cobalt series and to the Ramsay
Lake conglomerate is not definitely known.

Nipissing Diabase and Sudbury Norite.

Succeeding the deposition of the Cobalt series came the
intrusion of the quartz-diabase which gave rise to the silver
deposits of Cobalt. This intrusive is known as the Nipis-
sing diabase. As stated above, the Sudbury norite, with
which are genetically connected the nickel-copper deposits,
is similar in chemical composition and appears to be of the
same age.

Paleozoic Rocks.

To the north and east of Cobalt, limestone, with basal
conglomerate and sandstone, of Silurian (Niagara) age,
occurs as outliers on the pre-Cambrian.

With the exception of deposits of glacial and recent age,
no rocks younger than the pre-Cambrian are found in the
vicinity of Sudbury or Porcupine.

W. G. M.

Toronto, June, 1913.

THE SUDBURY AREA

A. P. COLEMAN.
CONTENTS.

PAGE

Introduction II

The Geology of Sudbury 15

Interior of the Nickel Basin 19

The Nickel Eruptive 24

The Nickel Deposits 26

Development of the Nickel Region 32

Literature on the Sudbury Region 34

The Moose Mountain Iron Range 35

Annotated Guide 40

Itinerary at Sudbury 42

INTRODUCTION.

The Sudbury region is especially known for its nickel
mines, the most important in the world; but the geologist
finds an almost equal interest in its eruptive rocks, which
include a remarkable basin-shaped laccolithic sill more than
a mile thick and covering 400 square miles of territory, and
its unusually complete set of pre-Cambrian formations, prob-
ably not surpassed by any other area of equal size in
America. The region displays also striated rock surfaces
and boulder clay, due to Pleistocene glaciers and shore and
deeper water deposits of ancient Lake Algonquin.

The scenery of the region is mostly of the " rocky lake "
character, but this is diversified with considerable stretches
of fertile farm lands. In many parts the original forest has
been destroyed by the lumberman and by fire, leaving the
rock hills bare, so that the geological structures are admir-
ably exposed; and in a few places sulphur fumes from roast
beds and smelters have destroyed all vegetation, allowing
rain to carve the drift materials and expose the glacier
smoothed rock surfaces beneath.

The most striking physiographic features of the region
are connected with the great basin-shaped sheet of the nickel
eruptive. This consists of an easily-weathered outer side of
norite blending into a resistant inner side of a pranitic char-
acter, whch has metamorphosed and hardened the rocks
above; so that after passing the irregular Archaean surface
which surrounds the basin, there is everywhere a depression
or trough, sometimes occupied by lakes, representing the
basic portion of the eruptive, followed after a mile or two
by rugged hills, made up of the acid portion and the meta-
morphosed sediments above.

After crossing this belt of rough hills the interior spreads
out as a low plain covered with old lake deposits, often
level as a prairie. From the farms of the interior one sees
the rim of the basin rising on all sides as ridges or hills
sometimes reaching 500 feet above the sheltered plain. The
basin is drained by Vermilion river and its tributaries,
which descend as fine cataracts and falls when their course
leads over the acid edge, or meander with a gentle current

through the old lake deposits of the interior. The spread-
ing out of the sheet of molten rock and its settling into a
synclinal basin have given a regularity to the topographic
forms not found in other pre-Cambrian regions, and rivers
and lakes and farms and railway routes are all adjusted to
the ancient rock structures.

Sudbury itself, the capital town of the region, lies some
miles southeast of the edge of the basin and rests upon older
rocks with a less orderly arrangement. They include near
Wanup and Quartz on the Canadian Pacific and Canadian
Northern railways, characterise rocks of the Grenville
Series, whose position with reference to the classification
adopted by the International Committee is somewhat uncer-
tain; and also a great series of other sediments older than
the Laurentian, which have recently been proved to lie
below the Huronian, and which have been named provision-
ally the Sudbury series.

The most recent classification of the pre-Cambrian in the
Sudbury region is as follows :

Post Keweenawan( ?) — Dikes of diabase and granite.

Keweenawan ( ?) — Xickel-bearing eruptive sheet.

Huronian — Upper Huronian (Animikie), conglomerate,
tuff", slate and sandstone.
— (Middle Huronian wanting.)
— Lower Huronian, basal conglomerate.

Laurentian — Granite and gneiss eruptive through older
rocks.

Sudbury Series — Copper Cliff arkose, McKim graywacke,
and Ramsay Lake quartzite.

Keewatin — Iron Formation, greenstones and green schists.

Grenville Series — Quartzite, sillimanite schists and gneisses
and crystalline limestone.

Whether the Keewatin and the Grenville series are of the
same age or not is uncertain, since the two groups of rocks
do not occur together.

As no fossil-bearing rocks have been found the position
in time of the later eruptives is somewhat doubtful, as indi-
cated in the table.

THE GEOLOGY OF SUDBURY.

The town of Sudbury rests mainly on stratified clay under-
lain by quicksand formed in glacial Lake Algonquin, but
hills of rock project above these lake beds, showing surfaces
that have been smoothed and striated by Pleistocene gla-
ciers. The chief rock within the town is McKim gray-
wacke, which is well stratified with thin slaty layers the
bedding showing distinctly on weathered surfaces. The beds
are usually steeply tilted and are even vertical against a lac-
colithic mass of gabbro toward the east side of the town.
The strike and dip vary considerably and in many places
the greywacke is brecciated and recemented, the crushing
having taken place, it is supposed, during the advent of the
nickel eruptive. The graywacke is often crowded with
small pseudomorphs after staurolite, suggesting contact
metamorphism, which may be accounted for by the effects
of the laccolithic gabbro and other eruptives in the region.

Toward the southeast on the shores and islands of Ram-
say lake, the graywacke is followed by pale gray quartzite,
well stratified in thick layers which are often cross bedded.
They have usually a dip of about 45 deg. with a strike of
northeast and southwest. The Ramsay lake quartzites form
an extensive group of rocks, having a width of six miles,
where widest, and an estimated thickness of 15,000 feet.
They appear to overlie the graywacke, though well exposed
contacts have not been found.

Areas of greenstone or greatly weathered gabbro pene-
trate the quartzite in various places, and granite or granitoid
gneiss of a Laurentian type cuts them toward the south and
southeast.

The quartzite, graywacke and a recrystallized arkose, ris-
ing as ridges somewhat to the west of the town, make up
the Sudbury series, which is not less than 20,000 feet thick.

The most interesting of the eruptives penetrating the
rocks just described forms a laccolithic range of hills in the
eastern part of Sudbury, where gabbro has tipped up beds
of graywacke and sometimes even overturned them slightly.
The gabbro is gray-green and much weathered, consisting
now mainly of hornblende and poorly preserved plagioclase;
but at various points on the hills there are large patches of
white rock, either " roof pendants " of quartzite partly di-
gested, or segregations of a pegmatitic kind. These patches

begin with a green band of hornblende on the outside, fol-
lowed by an intergrowth of long blades of hornblende with
white plagioclase. The latter on the inner side becomes
coarse " graphic granite " with interleaved quartz, and the
centre of the mass may consist of almost pure quartz. The
largest example of the kind, a mile south of Copper Cliff,
was worked as a quartz mine, and furnished thousands of
tons of fairly pure quartz used as flux at the smelter, ir
seems most probable that the coarse textured rock surround-

re-

structure in Gabbro, Sudbury.

ing the quartz is a sort of " reaction rim " about a partially
digested block of quartzite. A little pyrrhotite containing
some nickel occurs with these masses of quartz suggesting
a relationship to the nickel-bearing eruptive a few miles
to the northwest.

The sedimentary rocks of the Sudbury series mentioned
above were tilted and folded and penetrated by eruptives,
and then carved down to an uneven plain before the Huron-
ian began. On the upturned edges of the quartzite a coarse

boulder conglomerate rests nearly horizontally. This has the
characters of tillite, a matrix of graywacke enclosing angu-
lar, sub-angular and rounded stones of all sizes up to boul-
ders several feet in diameter. Among these stones are many
of quartzite and granite, the nearest outcrop of the latter
rock occurring five miles to the southeast. No striated
stones have yet been found in the tillite, perhaps because it
is almost impossible to separate the stones from the matrix.
Dr. Collins has traced this conglomerate northeast with

Structure in Gabbro, Sudbury.

scarcely a break to the basal conglomerate at Cobalt ; and
the present writer has followed it, with some intervals, to
the lower Huronian conglomerate of the typical Huronian
region toward the west.

The conglomerate, like the lower rocks, is often crushed
into a breccia composed of large blocks cemented by more
finely ground materials. This took place during the dis-
turbances caused by the advent of the nickel eruptive. The
tillite or conglomerate is the only lower Huronian rock
found, and the middle Huronian is entirely absent.

INTERIOR OF THE NICKEL BASIN.

The next rock in position is the great laccolithic sheet of
the nickel-bearing eruptive, which is bent into a boat-shaped
syncline, 17 miles wide and 36 miles long, from southwest
to northeast, with the square end of the boat at the latter
end. As the sheet is really much later in age than the over-
lying beds, the sedimentary rocks enclosed in it will be
described first. They were considered Cambrian by Dr.
Robert Bell, but no fossils have been found in them, and

Onaping- Falls over vitrophyre tuff.

petrographically they somewhat resemble the western Ani-
mikie (Upper Huronian), so that it seems better to class
them with the Upper Huronian, though their age cannot be
certainly fixed at present.

There are four subdivisions exposed in very regular suc-
cession in the interior of the basin, the Trout Lake conglom-
erate on the outside resting directly on the upper part of the
eruptive sheet, followed by the Onaping tuff, which forms
an inner and wider belt; and then by the Onwatin slate;
while the Chelmsford sandstone runs down the centre of
the basin.

The conglomerate is coarse textured and has generally
been greatly metamorphosed by the underlying eruptive

sheet so that its matrix is often changed to micropegmatite.
and but for the vaguely edged boulders it would not be
recognized as sedimentary. Often, too, there have been
shearing motions giving a schistose structure to the con-
glomerate, which has even been mapped as Laurentian.

The conglomerate passes gradually into the Onaping tuff,
which is well displayed at the beautiful falls of Onaping
river, where there is a descent of one hundred feet over

Anticline of Chelmsford sandstone, near Chelmsford.

these rocks. The tuff is formed of sharp-angled glass frag-
ments cemented by volcanic dust, and now transformed into
chalcedony, serpentine, etc. It may be called a vitrophyre
tuff, as suggested by Dr. Bonney, who first described it.

There is no distinct boundary between the tuff and the
Onwatin slate, which is black and highly carbonaceous,
sometimes containing ten per cent, of carbon. In it are
found the curious veins of Anthraxolite (anthracitic carbon)
which have aroused vain hopes of the discovery of coal.
The anthraxolite, which when pure, contains 95 per cent.

of carbon, as shown by Prof. Ellis, must have been
fluid in the beginning, probably bitumen driven from the
carbonaceous shale by the heat of the eruptive beneath. As
the black slate is the softest rock in the region, it has suf-
fered from erosion more than the rest, and is mostly covered
by old lake deposits.

The Chelmsford sandstone is dark gray and might almost
be called graywacke. It encloses numerous large oval con-
cretions of impure limestone. When the Animikie beds
were bent into the synclinal form the uppermost layers,
especially the sandstones, were thrown into compression and
rose as dome-shaped anticlinal ridges a few hundred feet
high. There must have been a dozen or more of these
elongated domes in the beginning, all stretching parallel to
one another and to the longest axis of the basin. Now the
domes are all more or less ruined, and some scarcely show
above the drift deposits. One of the largest, at Chelmsford,
is two miles long by a third of a mile wide, and rises about
150 feet above the plain. Several thick layers of sandstone
have been removed from the top, and buttresslike remnants
of beds rise from the fields on each side, so that its height
must have been much greater in the beginning. A good
example of a smaller anticline is crossed by the railway at
Larchwood, six miles west, where the dip of the beds on
each side is about 45 deg.

This sedimentary series, resting upon the nickel eruptive,
has an average dip inwards of 30 deg., and has been meas-
ured up with the following results :

r Chelmsford Sandstone . . 800 to 1,500

Upper Huronian (Animikie' \ Onwatii, Slate 3,800

v v j Onaping Tuff 3.700

I Trout Lake conglomerate 20 to 400

9,400

The black slate resembles the Animikie slate at Thunder
Bay, but the remarkable tuff of glass fragments has no
equivalent in the western Animikie. It appears that these
relatively soft sedimentary rocks, if they ever existed in
•other parts of the eastern pre-Cambrian, have been com-
pletely destroyed. Their preservation here is due to the
protection of the upturned edges of the nickel eruptive
basin, aided by the strengthening of the Trout lake con-
glomerate and of the lower part of the Onaping tuff by
metamorphic action due to the eruptive sheet.

THE NICKEL ERUPTIVE.

The most interesting and important feature of the region
is the laccolithic sheet forming the synclinal basin and pro-
viding the great deposits of nickel and copper ore which
have made the district famous. The sheet is 36 miles long
and 17 miles broad with a thickness varying from half a
mile to two miles and averaging a mile and a quarter. It
is estimated to contain 500 cubic miles of rock, and it was
once far larger, since it has lost much of its original dimen-
sions by erosion.

The sheet consists of norite on its lower side, passing
gradually into micropegmatite on the upper side. Blebs of
ore are often scattered thickly through the lower part of
the norite, and where there is a depression in the floor
beneath this, pyrrhotite-norite merges without any break
into ore bodies sometimes containing millions of tons of
pyrrhotite and other sulphides. Unquestionably all three
substances, ore, norite and micropegmatite, belonged origin-
ally to the great flood of molten rock which rose from some
hearth beneath and spread out over the old eroded surface
of ancient rocks, including the Sudbury series and the Laur-
entian gneisses ; and under the flat-lying Animikie sediments
just described. As the magma welled up from beneath, the
floor of older rocks collapsed into large or small blocks
which settled down allowing the sheet itself with the over-
lying sediments to assume the synclinal form.

Thus more than a mile's thickness of molten rock was
blanketed by 9,400 feet of sediments, so that the cooling
must have gone on extremely slowly, giving time for the
heavier materials to settle to the bottom, and also for the
upper, more acid part of the magma to metamorphose pro-
foundly the conglomerate immediatelv over it and to silicify
and harden the lower part of the Onaping tuff, as just men-
tioned.

The coming up and spreading out of the norite-micropeg-
matite sheet profoundly shattered all the adjoining rocks,
and almost everywhere beneath the sheet there is a sort
of breccia or conglomerate of fragments of the underlying-
rock sometimes cemented by norite or ore.

The freshest norite, which often occurs close to large
ore bodies and may enclose portions of the ore, consists
mainly of labradorite and hypersthene, with some ordinary

pyroxene and a few large bits of biotite. One finds also a
little interstitial quartz and a few distinct blebs of bluish
quartz. The most basic phase of the rock analysed con-
tains about 50 per cent, of silica, and the most acid example
of micropegmatite about 69 per cent., showing a consider-
able range from the bottom of the sheet to the top.

All the rocks of the district are cut by dikes of very fresh
olivine diabase, some of which are 200 or 300 feet wide,
and may be traced, as shown by Dr. Barlow, for seven
miles, passing through norite, ore and country rocks impar-
tially. This diabase and some dikes and irregular masses
of granite are the youngest rocks of the region and may date
from earlv Paleozoic times.

THE NICKEL DEPOSITS.

The nickel ores which give economic importance to the
region are of a very uniform and monotonous character.
In all the larger mines the ore consists of pyrrhotite in
largest amount with subordinate quantities of pentlandite,
(XiFe)S, and chalcopyrite. The pentlandite may be finely
disseminated through the pyrrhotite and not apparent to the
eye, but polished surfaces of the ore. as shown by Campbell
and Knight, prove its presence under the microscope. The
ore always contains small quantities of the norite minerals
and sometimes fragments of norite or country rock. The
country rock may be any of the older formations, sediments
of the Sudbury series, acid or basic eruptives, or Laurentian
gneiss, without in anyway affecting the ore deposit ; but no
ore deposit has yet been found without norite. " Xo norite,
no ore," is the law of the district. There are, however,
long stretches of the norite edge where no ore occurs, where
the sheet is unusually narrow, or where the country rock
bends inwards instead of outwards. There are cases where
the norite edge is gossan covered continuously for more
than a mile, as in the vicinity of the Murray mine.

The ore bodies mav be divided into two principal kinds,
marginal deposits, at low points or bays on the edge of the
norite : and offset deposits, where channels lead out from
such bays conveying the ore mixed with norite to various
distances from the edge, sometimes even three or four miles

Creighton mine, recent condition of open pit.

The best example of a marginal deposit is at Creighton,
where one of the largest bays of the norite edge has fur-
nished the greatest nickel mine worked in the district or
in the world up to the present. The Creighton mine began
as an open pit, which is now nearly 300 feet deep, with,
lower levels worked by underground mining. The country
rock is granitoid gneiss and the ore body which rests upon
it dips 34 degrees inwards towards the central line of the
nickel basin. The ore is unusually rich, containing about
6 per cent, of nickel and copper, the latter making up a
quarter of the whole, and specimens showing pentlandite
are often found. It may be distinguished from the enclosing
pyrrhotite by its octahedral cleavage and brassy color as
compared with the bronze of the more common mineral.
The greenish yellow of the chalcopyrite is more easily
recognised.

It is interesting to find that the dikes of fresh diabase
cutting the rock and ore in various directions are glassy
against the ore, which was a good conductor of heat, and
only fine grained against norite or gneiss where the chilling
was not so rapid.

The best examples of offset deposits are at Copper Gift",
where a large bay of norite narrows toward the southeast
into a dike-like band of norite and ore which ends in the
great columnar ore deposit of Xo. 2 mine. The open pit
gives a good opportunity to see the shape of a characteristic
offset deposit, which has been followed downwards for more
than 6od feet.

A quarter of a mile to the south is the once renowned
Copper Cliff mine, a still better example of this tvpe, which
reached nearly 1,300 feet in depth on an incline of 77
degrees to the east, and for years supplied the richest ore
in the district, averaging nearly 9 per cent. Most offset
mines are richer in copper than the marginal mines and the
Copper Cliff ore contained more copper than nickel, justi-
fying its name.

Two other deposits have been worked to the southwest
and south at intervals of a quarter of a mile and of three
quarters of a mile, but they were of minor importance. All
of these ore bodies are associated with some norite spotted
with blebs of ore. but they show no surface connections
with one another or with the main mass of norite and must

have been supplied by devious channels between the shifting
blocks of country rock. Whether these channels still exist
beneath the surface or were above the present level is un-
certain. Probably the present surface is thousands of feet
below the original one. so that connections from above
might have been eroded away.

The columnar deposits at Copper Cliff and Xo. 2 mine
are not the most extraordinary of their kind, since two still
smaller columns have been followed downwards for 1.600
feet at Victoria mine.

The Copper ClirT offset deposits occur in contact with
a variety of country rocks such as granitoid gneiss and
greenstone among eruptives. and graywacke and pink
quartzite of the Sudbury series among sediments, without
any change in the character of the ore : and they are cut by
dikes of granite and diabase which have likewise had no
appreciable effect in changing the original ores.

In addition to typical offset deposits where the connection
with the basic edge of the nickel eruptive is manifest there
is one very important band of gossan and ore which runs
nearly parallel to the edge of the norite with no suggestion
on the surface of any connection. This is the Frood-Stobie
offset north of Sudbury, the largest known body of ore in
the district. There must have been subterranean channels
through which the pyrrhotite-norite and ore reached their
present position in this unique case. The Frood-Stobie
offset runs as a narrow gossan covered ridge with one or
two interruptions for nearly two miles from southwest to
northeast, and touches several types of rock, such as gray-
wacke and greenstone, but nowhere comes within three-
fourths of a mile of the norite edge.

Diamond drill cores prove that the deposit dips at first
with an angle of 60 degrees or 70 degrees toward the norite.
while at a greater depth the inclination flattens decidedly
suggesting a broad underground connection with the parent
eruptive sheet.

The Frood-Stobie offset has been proved to contain more
than 35.000.000 tons of average ore and far surpasses in
magnitude any other known ore body in the Sudbury region.
It has already furnished half a million tons of ore and shafts
are now being sunk by both the Canadian Copper Compar-
and the Mond Company, so that it will soon add greatly to
the quantity mined in the district.

THE MOOSE MOUNTAIN IRON RANGE.

At Moose Mountain about 7 miles beyond the northern
side of the nickel basin and 33 miles from Sudbury by the
Canadian Northern Railway, one of the largest iron ore
deposits in Canada has been found. The iron formation here
is separated from the northern nickel range by a band of

Banded iron formation, Sellwood.

Laurentian consisting of granite, banded gneiss, greenstone
and green schist, all more or less cut by pegmatite dikes.
These rocks are far older than the nickel eruptive and
underlie the deposits of the northern nickel range as country
rock. The Sudbury series is lacking on this side of the
nickel basin, so far as known, and nothing suggesting the
Grenville series has been , found, so that the geology to the
north differs greatly from that to the south.

Moose Mountain, rising 280 feet above the plain and the
railway, though one of the most important examples of the
iron formation in the Keewatin of Ontario, presents less
than the usual variety in the accompanying rocks, and the
structural relations are more obscure than in some other
regions, such as the Helen Iron Range.

In most cases the iron formation of Ontario consists of
some form of silica interbanded with iron ore. either jasper
with hematite or cherty or quartzitic silica with magnetite
At Moose Mountain the latter material is found. Commonly
the iron formation occurs as synclinal belts enclosed in
green Keewatin schist; but a definite relation of this sort
has not yet been proved at Moose Mountain, perhaps
because the regularity has been disturbed by intrusions of
greenstone and granite. The accompanying rock is a
banded schist alternately light and dark gray. The
iron formation here has the usual steeply tilted attitude.
Often the banding is fairly straight and uniform for con-
siderable distances, but in many cases there has been
crumpling and sometimes crushing and faulting on a small
scale. The ordinary banded ore contains 36 per cent, of
iron, and from the results of stripping and diamond drilling,
the manager of the mine. Mr. F. A. Jordan, estimates that
there are 100.000.000 tons of ore of this grade. There are
also 6.000.000 tons of higher grade magnetite in which there
is much less silica and where the banding is less marked.
Here some green hornblende is interbedded with the
magnetite.

Laurentian-looking gneiss occurs just south of the iron
formation but its relations to the ore bodies are not very
certain ; though dikes of granite and less often pegmatite
cutting some of the outcrops of ore have probably come
from it.

The richer parts of the ore have been greatly fissured
and are penetrated in all directions by yellowish green bands
or veins of epidote, evidently the last mineral formed.
Beside these bands the magnetite is sometimes changed to
hornblende which gradually passes into the usual ore within
a few inches. The main ore body worked has been pro-
visionally classified by Prof. Leith as belonging to the
Pegmatitic type (Jour. Can. Min. Inst., Vol. XI, 1908, p.
93). He defines the type as including " ores which are

carried to or near the surface in magmas and are extended
from them in the manner of pegmatite dikes, after the re-
mainder of the magma has been partially cooled and
crystallised. They are deposited from essentially aqueous
solutions mixed in varying proportions with solutions of
quartz and the silicates." He has evidently in mind the
usual theory of the formation of the Kiruna and other
magnetite deposits in northern Sweden. In his soecial
reference to the Moose Mountain deposit he mentions that
the ore shows " such intimate relations with greenstones as
to suggest a direct derivation from them."

It should be stated, however, that some of this richer ore
is interbanded with belts of the poorer silicious type making
up the majority of the whole series of deposits, and it is
possible that the downward percolation of hot waters may
have produced the enrichment. The latest effect of cir-
culating fluids, the formation of epidote, is generally accom-
panied by an enrichment of the ore near the small veins of
that mineral.

Moose Mountain has been the first iron mine in Canada
to concentrate its ores magnetically on a commercial scale.
The higher grade ore is crushed to about inch size and
separated from the intermixed epidote and hornblende by
magnetic means, raising its iron contents to a merchantable
grade containing 55.50 per cent, of metallic iron. The
plant in use, though small and experimental, has provided
155,000 tons of ore for shipment.

This method is not effective for the 36 per cent, ore in
which the magnetite is intimately mixed with silica, and
within the past two years a new concentrating mill, much
larger and more elaborate, has been erected. Here the ore
is crushed to 100 mesh and separated magnetically by the
Grondal method. The finely divided magnetite is then com-
pressed to drive off most of the water, briquetted and finally
treated in a furnace which sinters it slightly and transforms
most of the magnetite into hematite.

Though not so large as the great magnetite deposits at
Kiruna and elsewhere in northern Sweden, Moose
Mountain promises to become a great producer of ore. The
Keewatin iron deposits of Ontario, with the exception of
the Helen and Magpie Iron Mines near lake Superior, are
usually similar to the one just described at Moose Mountain.

There is a good deal of dispute as to their origin, though the
original materials of the iron ranges are admitted by all to
have been sediments of some kind.

The map of the Moose Mountain iron deposits has been
prepared by Mr. E. Lindeman of the Mines Branch at
Ottawa, who recently carried out a detailed magnetometric
survey of the property.

ANNOTATED GUIDE.
Toronto to Sudbury via Canadian Pacific Railway.

Miles and
Kilometres.

o. Altitude 254 feet. (77.4 m.) Leaving Toronto

(Union Station), by way of Parkdale and West
Toronto, the train passes through a manufactur-
ing district as far as Weston. The country is
heavily covered with Pleistocene deposits, con-
sisting of boulder clays, and stratified clays,
sands and gravels, which conceal the underly-
ing Paleozoic rocks. At Weston the clay is
used for the manufacture of red brick.

The surface presents on the whole a rolling
appearance, and is very suitable for farming
purposes. Sometimes the surface is intersected
by ravines, and sugar-loaf hills have been carved
from the drift, as around Woodbridge and
Humber.

About 70 miles (no km.) north of Toronto
old lake deposits become abundant. Half a mile
south of Carley, stratified sand showing cross-
bedding is splendidly shown in a ballast pit east
of the track.

96. m. One mile north of Coldwater ]unction the

154.5 km. first outcroppings of rock occur. These are of
banded gneiss of Laurentian age projecting as
rounded knobs through the drift.
99. m. North of Lovering rock exposures become

159.3 km. more f recent, and soon a typical Laurentian area
is entered.

108.5 m. North of the crossing of the Severn river

174.1 km. farming- land almost disappears occurring only

in small scattered areas.

This Laurentian area stretches northward
continuously along this route for 150 miles
(240 km.). The Laurentian consists chiefly
of dark grey micaceous and reddish granitic
gneisses with dikes of red granite or pegmatite.
120. m. Bala is the western gateway to the Muskoka

193. km. lakes district, famous as a resort for tourists.
132. m. Altitude 742 ft. (226. m.) Muskoka, a divis-
212.4 km. ional point, is on Lake Joseph, one of the largest

of the Muskoka lakes.
155. m. At Parry Sound there is a splendid view of

249.4 km. Georgian Bay from the train as it crosses the

1,700-foot (518 m.) steel viaduct which is 120
feet (36.6 m.) above the Seguin river. (518 m.)
181. m. Another view of Georgian Bay is obtained

291.2 km. from Point au Baril.

195. m. Altitude 575 (175.3m.). Byng Inlet is
313.7 km. located on an arm of Georgian Bay. At this
point there are extensive lumbering operations.

This region of Laurentian rocks is a striking
peneplain with little soil and numerous clear-
water lakes and swift running streams. The
marks of glaciation are everywhere seen.
255. m. Fragmental, pre-Cambrian, rocks are first

410.3 km. observed two miles south of Romford Junction.

They consist of layered quartzite. At Romford
the quartzite strikes east and west and dips 45
degrees S.

On the north shore of Ramsay lake, three
and a half miles west of Romford, a comglom-
erate, which rests unconformably on the quartz-
ite, is exposed in the railway cuttings. It out-
262. m. crops along the lake and railway to the town of

421.5 km. Sudbury.

ITINERARY AT SUDBURY.
First Day.

8 a.m. — Sudbury to Ramsay Lake.

Sudbury, alt. 855 ft., (260.6 m.), chief town of the
nickel region with a population of about 5,000, is situated
on a flat plain of silt deposited in a bay of lake Algonquin.
Above it rise hills of the Sudbury series of rocks.

A walk of two hours' duration will be taken through the
town to Ramsay lake, crossing well stratified and steeply
tilted greywacke (McKim greywacke), partly brecciated
during the advent of the nickel eruptive. On the shore of
the lake and on islands pale grey quartzite dips at an angle
of 45 degrees southwest. It extends in that direction six
miles (9.6 km.) and is estimated to have a thickness of
15,000 feet (4,500 m.). North of Ramsay lake the Basal
Huronian tillite is seen resting unconformably on the quartz-
ite. It contains pebbles and boulders of quartzite, grey-
wacke and granite.

Northwest of the conglomerate a hill of la~colithic gabbro-
will be visited, halting first at a dike of fresh olivine diabase.
Climbing the hill there are good views of the town and of
Ramsay lake. On top of the hill one may study certain
curious " roof pendants " (or acid segregations) having
quartz in the centre, followed by pegmatite and by coarse-
grained hornblende-albite rock, with a rim of hornblende in
large bladed crystals.

From the laccolithic hill the party will return through
the town to the special train. The total distance walked is
two miles (3.2 km.).
10. a.m. — Sudbury to Levak.

Leave Sudbury by special train on the main line of the
C.P.R. going northwest for iy2 miles (2.4 km.) through
McKim greywacke, followed by pink arkose, (Copper Cliff
arkose), following for some distance a great dike of diabase
which may be seen in cuttings. After a steady ascent of
four miles (6.4 km.), the latter part through greenstone and
granite, the summit is reached at Murray mine, alt. 992
feet, (302.3 m.), where the railway crosses the gossan-
covered edge of the nickel-bearing norite. Murray mine is
one of the oldest of the nickel mines in the district but has
not been regularly worked for many years.

The railway runs for two miles (3.2 km.) through a
nearly flat plain formed of the dark grey, easily weathered
norite, cut in one or two places by later granite. The
norite then merges into reddish grey micropegmatite rising
as rugged hills.

At Azilda, alt. 891 (271.8 m.), 7 miles (11.3 km.) from
Sudbury, the railway enters the interior plain of the nickel
basin, having come in by the easiest pass through the acid
edge of the nickel eruptive. This plain of farmlands is
formed of silt deposited in a bay of lake Algonquin, and
Whitewater lake, a mile to the south, lies at the boundary
of the interior sedimentary rocks against the eruptives. All
round the basin, which is 35 miles (56.3 km.) long and 10
(16. 1 km.) wide, may be seen hills of micropegmatite and of
conglomerate which it has metamorphosed.

At Chelmsford, alt. 888 feet (270.6 m.), 12 miles
(19.3 km.) northwest of Sudbury, in the middle of the
basin, low anticlinal domes of sandstone begin, one of the
largest lying southeast of the village.

At Larchwood, alt. 885 feet (269.7 m.), 18 miles (29
km.) from Sudbury the railway cuts through one end of a
ruined dome just east of the Vermilion river, which crosses
the upturned edges of sandstone as pretty rapids.

At Phelans, alt. 937 (285.6 m.), 21 miles (33.8 km.)
from Sudbury, the railway ascends a gravel terrace, a
delta deposit of the river where it entered lake Algonquin,
and not far beyond is the beautiful falls of Onaping river,
more than 100 feet (30.4 m.) in total height, over Onaping
tuff, the third member of the Animikie as found in the
nickel basin.

At Levak siding, alt. 1,020 feet (310.9 m.), 24 miles
(38.6 km.) from Sudbury, the railway is in the midst of
high and rugged hills of micropegmatite.

Three miles beyond, near Windy lake, alt. 1,221 feet,
(373.7 m.), the basic edge of the nickel eruptive is found.
A few hundred yards of drift, including an esker ridge,
separate the last outcrop of norite from the Laurentian,
which rises as the usual hummocky hills of gneiss.

After traversing the whole width of the nickel basin by
train it is intended to halt for a study of various points of
interest on the way back. A walk lasting two hours and
covering about 3 miles will be made along the railway east-

wards from Windy lake, giving an opportunity to examine
Laurentian granitoid gneiss near Winch- lake and outcrops
of fresh norite to the east. Unfortunately the contact of
the norite with the gneiss is hidden by fluvio-glacial
deposits.

Continuing eastwards the gray norite passes into a
reddish, syenitic-looking intermediate rock, and the valley
narrows between precipitous hills at Levak siding, where
the train will await the party and lunch will be taken.

After lunch the walk will continue for two miles to
Onaping falls and Phelan. The micropegmatite phase
(acid edge) of the nickel eruptive occurs as a rather pale
gray rock when Onaping river is reached. Next is seen
the basal conglomerate of the Animikie much metamor-
phosed by the underlying eruptive sheet ; and this passes
at the beautiful Onaping falls into vitrophyre tuff crowded
with small glass fragments now turned to chalcedony or
serpentine. The walk of about 2 miles ends at Phelan
where there are good sections of the delta gravels formed
by Onaping river in a bay of ancient lake Algonquin. Here
the train will be taken to Larchwood.

At Larchwood a short walk will be made to a good
example of the anticlinal hills of the interior basin. Ver-
milion river and the railway make their way across the
ruined southeastern end of the anticline.

The train will then be taken to Murray, where a walk
of about 2 miles will show the gossan covered basic edge
of the norite resting on a complex of ancient lavas showing,
in places, amygdaloidal and pillow structures. The lava
when fresh has the composition of a norite, but is earlier
than the nickel-bearing norite and more basic in character.
Following a suggestion of Dr. Miller it is r>ror>osed to call
this effusive variety of norite Sudburyite. Its relation to
norite is similar to that of basalt to gabbro.

A hill of this rock just south of the old Elsie nickel mine
affords a good view of the nickel range and the interior
basin.

At Murray diamond drills will be seen at work determin-
ing the attitude and thickness of the nickel ore body, which
is already known to reach a depth of 1,100 feet and to in-
clude more than 10.000,000 tons.

Return to Sudbury in the evening.

Second Day.

7 a.m. — Leave Sudbury by Algoma Eastern railway for
Creighton, passing for 2 miles (3.2 km.) through grey-
wacke, followed for a mile (1.6 km.) by arkose and then
by greenstone. At 31/o miles (5.6 km.) west a branch runs
south to Copper Cliff. Beyond this greenstone and granite
extend to the norite of the Copper Cliff offset, here about a
mile (1.6 km.) wide. For the rest of the journey the rail-
way runs southwest near the contact of the norite with
coarse granitoid gneiss.

Creighton, alt. 973 feet (296.5 m.) is 11 miles (17.7 km.)
by rail west of Sudbury. The party will walk south through
the village to a hilltop of granite and gneiss from which
there is a broad outlook over the gossan edge of the nickel
range and the mine with its surroundings. The hill displays
interesting crush conglomerates as well as small faults
caused by the arrival of the nickel eruptive. A walk will
then be made past the east end of the mine to a character-
istic contact of norite with the older gneiss ; after which the
gossan hill and the great open pit, 300 feet (91.4 m.) deep,
will be visited. Those who wish may descend 60 feet
(18.3 m.) to the first level of the mine, following the foot
wall of the ore body.

Specimens of pyrrhotite, chalcopyrite and probably
pentlandite may be obtained, as well as of pyrrhotite-
norite, ordinary norite, and diabase, the latter cutting the
ore.

10 a.m. — Return by the A.C.R. to Clarabelle junction,
where the Canadian Copper Company's line will be taken
south for 2 miles (3.2 km.) to Copper Cliff.

The line passes through the great roastyard where heaps
of ore from the Creighton and other mines may be seen at
every stage, some in process of building, others steaming
with sulphur fumes, and others forming rusty heaps of well
roasted ore.

Beyond this is the rockhouse of No. 2 mine, and then
the large buildings and stacks of the smelter, followed by
the town of Copper Cliff with its polyglot population of
2,500, mainly from Finland and southeastern Europe.

A walk will be taken to Lady Macdonald lake,
where the edge of the norite narrows to a funnel leading to

the long and important Copper Cliff offset, passing through
granitoid gneiss, greenstone and greywacke.

Xo. 2 mine, with its open pit 300 feet (91.4 m.) deep,
in a typical columnar offset deposit.

The Copper Cliff mine itself is not now working but will
be visited as the richest and one of the most important of
the early mines. The ore body formed an irregular
chimney which has been followed for 1,300 feet (400 m.)
on an incline of 70 degrees to the east.

After visiting Copper Cliff the party will be taken to the
smelter, 2-3 of a mile (1.1 km.) northeast, where officers of
the Canadian Copper Company will guide them through the
various buildings and explain the processes. The plant is
one of the largest and most complete in North America.

The destruction of all vegetation in earlier years by roast
beds near the town has allowed rain erosion of a striking
kind on the old lake deposits in and near Copper Cliff.

During the afternoon the party will return to Clara-
belle junction and travel 4 miles (6.4 km.) northeast on
the Canadian Copper Company's private railway to Frood
or Xo. 3 mine, passing most of the way through greenstones.

At Frood the gossan-covered ridge will be ascended to
give an idea of the largest known nickel deposit in the world,
estimated to contain more than 35.000.000 tons of ore,
perhaps even 100.000.000 tons. It extends almost unbroken
for a mile to the southwest and almost as far to the
northeast, where the Stobie mine once produced more than
400.000 tons of ore. After testing it with the diamond drill
the Canadian Copper Company has sunk two shafts and
begun work on the deposit, and the Mond Xickel Company,
which owns the Frood Extension, taking in a part of the
centre of the ridge, is sinking a third shaft.

The Frood-Stobie offset, unlike all others, shows no
surface connection with the main nickel range, from which
it is separated by about a mile (1.6 km.) of granite hills.
The deposit may be described as a parallel offset. It doubt-
less has underground channels connecting it with the norite
to the northwest, since drill holes show that the ore body
dips that way.

Evening. — Return to Sudbury, where a complimentary
banquet will be given by the Board of Trade for excur-
sion A 3.

Third Day.

Leave Sudbury early in the morning by a branch of the
Canadian Northern railway running 5 miles (8 km.) north
and east to Sudbury junction, crossing a plain of old lake
deposits (Algonquin) and rounding the hill of laccolithic
gabbro in the eastern part of Sudbury. Near Sudbury
junction quartzite may be seen to the south and east.

At Sudbury junction the Sudbury branch joins the main
line 261.7 miles (421. 1 km.) north of Toronto.

From the junction the line runs northwest through
quartzite for two miles, followed by greywacke and green-
stone, until the basic edge of the nickel eruptive is reached.
Here the line turns north, passing Garson lake, which is in
the micropegmatite phase of the eruptive. The whole width
of the eruptive at this point is 2^4 miles (4 m.), and the
norite and micropegmatite are like those seen at Levak.

Passing the hilly acid edge of the eruptive and the Trout
lake conglomerate, the flat interior plain of sand and silt
deposited in a bay of lake Algonquin is entered. To the
south, east and north can be seen the rugged inner rim of
the nickel eruptive.

At Hanmer, 271.8 miles (347.4 km.) north of Toronto,
a hill of Onaping tuff rises to the east, and a mile or two
north black slate is seen near Onwatin lake.

The railway now follows the valley of the Vermilion
river. To the west there is a high terrace of fluvio-glacial
gravel, and at mile 273 the beach gravels of lake Algonquin
are used for railway ballast.

Near mile 278 tuff may be seen passing into conglo-
merate at the northern side of the basin, and just beyond
there are the usual hills of the " acid edge." The basic or
norite edge of the nickel eruptive occurs at Nickelton
junction, where the Nickel Range railway runs 4 miles
(6.4 km.) east to Whistle mine.

To the north of the junction the railway enters the
Laurentian, crossing coarse red granite and granitoid gneiss,
with bands or larger areas of green schist or greenstone as
far as Sellwood junction at mile 284.3.

From Sellwood junction a branch runs 5 miles (8 km.)
northwest to Sellwood, where the Moose Mountain iron
mines will be visited.

9 a.m. — No. i mine, near the brow of the hill, is worked
largely as an open pit where magnetite more or less inter-
banded with hornblende and green epidote occurs, and a
fault plane forms a slickensided wall on the west side.
Granite occurs as dikes in greenstone and green schist near
the ore, but does not actually touch it.

In a large stripping a quarter of a mile west granite
dikes are seen penetrating the ore or running parallel to its
banding.

A walk of a mile, mostly over drift deposits but passing
some banded Keewatin schist, leads to the iron dam, or No.
2 mine, where the ore is very different, consisting of inter-
banded silica and magnetite without hornblende or epidote.
This ore is leaner, containing only 36 per cent, of iron.
Where the iron formation crosses the Vermilion river inter-
esting crumplings and foldings of the banded ore may be
seen.

Half a mile farther north, near the new concentrator,
a stripping shows banded ore cut by dikes of granite and
by thin seams of epidote. A variety of interesting small
scale structural features can be seen here, such as anti-
clines and synclines and faults of different dimensions.

Officers of the Moose Mountain iron mine will take the
party through the mill and explain the methods of magnetic
separation and briquetting, by which the 36 per cent, ore
furnishes a high-grade product. Those who wish may visit
a saw mill at work near the village.

Afternoon. — Leave for Sudbury. If time permits a stop
may be made at mile 278 to observe a good contact of the
micropegmatite with the Trout lake conglomerate.

Towards evening the smelter of the Mond Nickel
Company at Coniston will be visited, giving an opportunity
to see the latest and one of the most complete smelting
plants in Canada.

Arrive at Sudbury in the evening.

4-7

THE COBALT AREA

WiiyLET G. Miller.

CONTEXTS.

PAGE

Introduction 52

The Rocks and Their Relationships 59

Age Relations of Rocks of Cobalt and Adjacent

Areas 62

Notes on the Rocks 63

Keewatin 63

The Temiskaming Series 64

Lamprophyre Dikes and Lorrain Granite. . 66

The Cobalt Series 69

The Xipissing Diabase 80

Dikes of Aplite or Granophyre 85

Basic Dikes 86

Paleozoic 88

Pleistocene 89

The Cobalt-Silver Veins 90

Origin of the Veins 91

Former Vertical Extension of Veins 95

Relation of Wall Rock to Ore 96

Ores and Minerals 97

Order of Deposition of Minerals 100

Mining and Milling 100

Bibliography 100

Annotated Guide Sudbury to North Bay 102

North Bay to Temagami, Cobalt and Hailevburv . . 104

INTRODUCTION.

In 1903, during the construction of the Temiskaming
and Northern Ontario Railway, which is owned and oper-
ated by the Ontario Government, rich veins of cobalt-silver
ore were discovered near what is now known as Cobalt
station. The railway track runs almost over the top of
one of the most important veins yet found.

At the time the discovery was made, the veins attracted
little attention, the discoverers not being men whose vocation
was that of prospecting or mining.

Xiccolite is a characteristic mineral of the area, and,
as its German name, kupfer-nickel, indicates, its color is
somewhat like that of copper. Hence, it is not surprising
that some of the first persons to see the deposits mistook the
niccolite for copper ore. and, not having their attention
drawn to the native silver, which occurred in profusion in
parts of the veins, should have decided that the deposits
were of the less precious metal. A sample of the niccolite,
received at the Bureau of Mines toward the end of October
of the year mentioned, aroused the writer's interest and he
decided to visit the locality from which it came.

The great Sudbury nickel area lies 90 miles to the south-
west of Cobalt, and in a report on a trip of exploration to the
vicinity of what is now Cobalt, in 1901, the writer had said:

" It will be seen from what has been stated on preceding
pages that the district examined contains as great a variety
of rocks as probably any other part of the Province of equal
area. . . .

" Although few discoveries of economic minerals have
been made in this territory, it may reasonably be expected,
judging from the character and the variety of the rocks, that
deposits of value will be found when the district is more
carefully prospected, as it will be in a short time, owing to
the rapid settlement which is now taking place. ... It
would seem that at least some of the conditions of the
Sudbury district are repeated in this more eastern field."*

*llth Report, Ontario Bureau of Mines, p. 229.

Naturally, on the receipt of the sample of niccolite, it
appeared that this prediction might have been verified, and
that deposits of nickel vastly richer than those of Sudbury
might have been discovered.

On examining the veins then discovered, four in number,
all near the shore of Cobalt lake, an unexpected and aston-
ishing assemblage of minerals was seen, the most prominent
being native silver, niccolite, smaltite and cobalt bloom. In
the first paper he published on the area, describing one of
the veins, the writer said:

" Here a perpendicular bare cliff, 60 or 70 feet high,
faces west. The vein. . . . cuts this face at right
angles, having an almost vertical dip. . . . "When I saw
it first it had not been disturbed. Thin leaves of silver up to
two inches in diameter were lying on the ledges and the
decomposed vein matter was cemented together by the metal,
like fungus in rotten wood. It was a vein such as one reads
of in text-books, but which is rarely seen, being so clearly
defined and so rich in contents."*

The veins are narrow, averaging not more than 4 inches
(10 cm.) in width. This feature discouraged certain of the
first mining engineers who examined the outcrops, and
caused them to doubt whether the veins were of economic
importance. However, the large number of veins and their
great richness has more than compensated for their narrow-
ness.

It was soon proved by comparatively little work that
Cobalt was really a " poor man's camp." One of the first
operators, for instance, extracted ore having a value of
approximately $250,000 at a total cost of $2,500. Statistics
show that during the period of mining in the area dividends
distributed have been equal to over fifty per cent, of the
value of the output.

In the earlier years of mining there were no refining
plants, in North America at least, that could economically
treat the ores. Owing to the unusual and complex char-
acter of the ores there was waste of other constituents in
extracting silver, there being present in addition to the
precious metal, arsenic, cobalt and nickel in important
quantities.

*Eng\ and Min. Jr., Dec. 10th, 1903.

The Cobalt area is not unique in Ontario in possessing
an unusual ore, other representative economic minerals
of the Province when discovered being without a market or
requiring the development of a refining process. The
Sudbury deposits, for example, were opened up for copper,
nickel being afterwards found to be present. A consider-
able period elapsed before refineries were developed and a

h '(""• Canton <<<t ,>„/,, <,vv,

i* . • > *• ' ■

/V 1 *>„>"■, ', <!v"'" -••^•'^wC9st*

Part of a map published in 1744, showing- that the argentiferous
galena deposit on the east side of lake Temiskaming (Ance
a la mine), about nine miles from Cobalt, was known at that
date.

market made for the nickel by proving to the nations of
the world its value as a constituent of steel for armour
plate. Again, in the earlier years of apatite mining in
Ontario, the amber mica, which is now so highly prized,
associated with this mineral, was thrown on the waste heaps.
And when the corundum deposits were discovered, a process

had to be developed for milling the rock and a market had
to be made for the material. Other instances could be cited,
but the examples given show that the characteristic of the
minerals mined in Ontario's pre-Cambrian rocks is unique-
ness.

It is gratifying to know that within the comparatively
few years that mining has been prosecuted at Cobalt, plants
capable of refining all of the constituents of the ore have
been erected in Ontario, the processes employed being either
improvements on those in use elsewhere or invented espec-
ially for these ores, such as that employed at the Nipissing
mine for the extraction and refining of silver. This metal
is refined at several other plants, and white arsenic and
cobalt and nickel oxides are produced. The plants for re-
fining cobalt oxide in Ontario are of capacity sufficient to
supply the world's demand for the material. The white
arsenic produced from Cobalt ores represents about 20 per
cent of the world's output. Cobalt is the world's greatest
producer of silver, its output representing about 13 per cent
of the whole.

In 1904, the year in which the first shipments were made,
there were produced 158 tons of ore. The average percent-
ages of the four metals in this ore were :

Silver 5.34 per cent., or 1,309.33 ounces per ton.

Cobalt 10.21 " "

Nickel 8.86 " "

Arsenic 45-56 " "

In 1905 there were shipped 2.144 tons of ore of the
following composition :

Silver 3.90 per cent., or 1,138.72 ounces per ton.

Cobalt 5.50 " "

Nickel 3.49 " "

Arsenic 25.60 " "

The ore shipped till near the end of 1907 was sorted by
hand, or with crude mechanical appliances. Since then
extensive concentrating plants have been erected.

For some time after mining began at Cobalt, the ore was
shipped to the sampling works of Ledoux and Company,
New York. The richest shipment contained 7,402 ounces
of silver to the ton, the next in order being 6,909; 6,413;
6,163 and 5,948 ounces to the ton. The average per-
centages of other metals in the 366 carload lots sampled by
this firm were: cobalt, 5.99; nickel, 3.66; arsenic, 27.12.

Concerning the high-grade ore at Cobalt, Mr. R. B.
Watson recently has said : "A typical ore carries 10 per cent,
silver, 9 per cent, cobalt, 6 per cent, nickel, and 39 per cent,
arsenic ; the rest is lime, silica and smaller amounts of
antimony, iron, sulphur, tellurium, etc."*

The most productive vein in the area is that known as
the Carson, on the Crown Reserve property. It has been
estimated that this vein, with its extension on the Kerr Lake
property, will have produced before being exhausted
20,000,000 ounces or more of silver from that part of it
above the 200-foot level.

The richness of the ore in various mines is well shown
by what it has cost, on the average, to produce an ounce of
silver. In 191 1, for example, the cost per ounce, including
mining and all other expenses, given in the annual reports
of certain companies, was : at the Crown Reserve, 10.761
cents per ounce; at the Coniagas, 8.8; at the Nipissing,
13.95 ; and at the Kerr Lake, 14.69.

The chief object in building the Temiskaming and
Northern Ontario railway was the development of the
agricultural areas at the head of Lake Temiskaming, to the
north of Cobalt. It was also felt that the railway would
increase the value of the timber lands through which it
passed, but, it is safe to say, the most sanguine supporters
of the policy of railway building little dreamed of the
mining development to which the construction of the road
would lead. It is true that mining at Sudbury had been
pursued for some years before it was decided to build the
railway into the Temiskaming country, but Sudbury had
never excited much interest among the people of Ontario.
Those who were inclined to invest in mines had little faith
in the mineral resources of their own Province. The dis-
covery of Cobalt, however, has given confidence in the Pro-

*Eng\ and Min. Jr., Dec. 7th, 1912

vince's mineral industry and has led to the development of
Porcupine and other areas tributary to the railway. The
value of the ore produced at Cobalt, in less than ten years,
is equal to about five times the cost of constructing and
equipping the 252 miles of railway from North Bay to
Cochrane, together with branch lines, and the dividends
alone are equal to two and a half times the total cost of the
railway.

Moreover, the discovery of Cobalt, which lies near the
southern edge of the great pre-Cambrian regions that occupy
nearly one-half the surface of Canada's 3,750,000 square
miles of territory, has given confidence in these regions as
storehouses of economic minerals and ores that future pros-
pecting will bring to light.

THE ROCKS AND THEIR RELATIONSHIPS.

At first, owing to the surface being covered with green
timber and to the presence of much drift material, contacts
and good exposures were difficult to find. Now, that the
timber has been removed parts of the area have almost the
appearance of a large model, e.g. between the northwestern
face of Mount Diabase and Peterson and Cart lakes, or on
the Nipissing property to the west of Peterson lake, where
the loose deposits have been removed from the surface by
hydraulicing.

From the maps of the area that have been published, it
will be seen that there is considerable variety in the pre-
Cambrian series. On the shores and islands of Lake
Temiskaming, a few miles to the north or northeast of
Cobalt station, the Clinton and Niagara of the Silurian
system also show prominent outcrops. Between the
Niagara and the Pleistocene or Glacial there are no form-
ations represented in the district.

The following table shows the subdivisions, based on age
relations, that have been made among the rocks of the
Cobalt area proper. Representatives of most of these sub-
divisions of the pre-Cambrian are found in other areas that
have been carefully mapped in the surrounding region.

10 s o to 20 jo Ki I o metres

N.W.-S.E. and X.E.-S.W. lines of regional disturbance in the district
of Temiskaming- and the cobalt-silver areas.

In the Porcupine gold area, one hundred miles to the
northwest of Cobalt, the Keewatin and Temiskaming series
are prominent. The Cobalt series is also present in this
area, and certain dikes are believed to represent the Nipis-
sing diabase of Cobalt.

In the Gowganda silver-cobalt area, which lies fifty or
sixty miles to the west of Cobalt, the Nipissing diabase and
Cobalt series occupy much of the surface. The Temiskam-
ing series is found in good exposures in part of the area.
The latter series has also been found at Swastika and
Larder lake, at Abitibi lake, 75 miles north of Cobalt, and
eastward across the boundary in Quebec. It is thus known
to occur at various points over a large region.

It is possible that unconformities that have not been dis-
covered exist in the pre-Cambrian of the Cobalt and adjacent
areas. Moreover, the relationship which the Cobalt and
Temiskaming series have to the fragmental rocks of the
classic Huronian area of the north shore of Lake Huron is
not known. Hence, in the following table the name Huron-
ian is not employed. If the Huronian is considered to
include all the post-Laurentian and pre-Keweenawan frag-
mental rocks of the region, then both the Cobalt and Tem-
iskaming series come under this heading.

The dual subdivision of the pre-Cambrian into Algonkian
and Archean, or Proterozoic and Archeozoic, employed by
many authors, is not adopted by the writer, since he believes
that the Grenville series, which includes limestones and other
sediments of great thickness, is of pre-Laurentian age.
Thus a dual subdivision of pre-Cambrian rocks, based on
arguments that have been employed in its behalf, fails. If
a name is desired for the pre-Cambrian rocks, to correspond
with Paleozoic and Mesozoic, the well-known name Eozoic
may be used.

Age Relations of Rocks of Cobalt and Adjacent Areas.

PALEOZOIC

SILURIAN
Niagara

(Great unconformity.)

EOZOIC OR PRE=
CAMBRIAN

LATER DIKES

NIPISSING DIABASE

(Intrusive contact.)

COBALT SERIES

(Unconformity.)

LORRAIN GRANITE

(Intrusive contact.)

LAMPROPHYRE DIKES

(Intrusive contact.)

TEMISKAMING SERIES

(Unconformity.)

Prominent outcrops of Niagara limestone,
with basal conglomerate and sandstone, occur
on some of the islands and the shores of the
north end of lake Temiskaming-.

Aplite, diabase, basalt.

This diabase, which is of such great interest
in connection with the cobalt-silver veins, is
believed to be of Keweenawan age. Certain
aplite dikes are genetically connected with
the diabase.

The Cobalt series includes conglomerate,
greywacke and other fragmental rocks.

This granite occupies a considerable part of
the township of Lorrain and has large ex-
posures elsewhere in the vicinity of lake
Temiskaming.

Lamprophyre dikes are to be seen near some
of the mines at Cobalt.

Like the Cobalt series, the Temiskaming
consists of conglomerate and other fragmental
rocks.

KEEWATIN COMPLEX The Laurentian, gneiss and granite, which

in age lies between the Keewatin and Temis-
kaming, is absent in the Cobalt area proper,
but is found in the surrounding region.

Under the heading Keewatin are grouped
the most ancient rocks of the region. They
consist essentially of basic volcanic types,
now represented by schists and greenstones,
together with more acidic types, such as
quartz-porphyry.

With the Keewatin are included certain
sed'ments, such as iron formation or jaspilyte,
dark slates and greywackes, which probably
represent the Grenville series of southeastern
Ontario.

Certain dike rocks that are grouped with
the Keewatin may be of post-Temiskaming
age, but since they have not been found in
contact with the Temiskaming series their
age relationships are unknown.

NOTES OX THE ROCKS.

KEEWATIN

The Keewatin rocks, of the Cobalt area proper,
fall into four groups: (i) Basalts, (2) Diabases and
other basic rocks, (3) Acid intrusives, (4) Sediments.
Of these the basalts are the most common. The diabases
are also of common occurrence, although they are not so

Torsion cracks in Keewatin greenstone, Cobalt.

widely distributed as the basalts. The acid intrusives are of
infrequent occurrence in the Cobalt area. Thev include
felsite, feldspar-porphyry and quartz-porphyry. The sedi-
ments grouped with the Keewatin include iron formation
(jaspilyte, chert and greywacke), graphite schists and
slates.

Many of the basic, igneous rocks of the Keewatin have
been rendered schistose and their original character cannot
now be definitely determined.

The acid intrusives of the Keewatin are on the whole
younger than those of more basic composition. Certain
diabases are intrusive into the basalts and iron formation.

No granite, or granite gneiss, older than the Lorrain
granite, occurs in the immediate vicinity of Cobalt, but
certain pebbles and boulders in the conglomerates of the
silver area have been derived from the Laurentian.

The name Laurentian is applied to granite or granite
gneiss, typically of grey color, the gneiss frequently poss-
essing alternate dark and light colored bands. The well-
banded gneiss owes its composition and structure to the in-
clusion of fragments and masses of Keewatin in the intrus-
ive granite, which have been squeezed or drawn out.

The Laurentian intrudes both the Keewatin and the
Grenville series. The Temiskaming is the oldest fragmental
series known in the region that is of post-Laurentian age.

THE TEMISKAMING SERIES

The Temiskaming series is composed of conglomerates,
greywackes and slates. The conglomerates show a great
variety of pebbles, including the following: basalt, diabase,
green schist, pyroxene or hornblende-porphyry, quartz-
porphyry, feldspar-porphyry, felsite, jaspilvte, grey, white
and red cherts, grey granite, granite gneiss and coarse
porphyritic syenite with crystals of feldspar one-half to one
inch in length.

The Temiskaming series is generally distinctly bedded,
and the strata are everywhere seen to have been tilted up
until they now rest in a vertical, or almost vertical, attitude.
Cross-bedding has been noted in some of the greywackes.
Along the shores of lake Temiskaming, between Haileybury
and New Liskeard, the strike ,Js easterly, observations)
giving strikes of N. 60 degrees to 70 degrees E., and steep
dips to the south. At the northwest corner of lot 8, in the
second concession of Bucke, the strike is N. 20 degrees W.,
with steep dips to the east. In various places the series is
intersected by quartz stringers a few inches in width and a
foot or more in length.

An unconformity is inferred to exist between the Lauren-
tian granites and gneisses and the Temiskaming sediments,
because granite, syenite and granite gneiss pebbles are found
in these sediments.

5—'

The Temiskaming series was invaded, first by lam-
prophyre dikes, and later by the great mass of Lorrain
granite. Good contacts of the Lorrian granite and Temis-
kaming series are to be seen immediately south of the
Temiskaming mine, and at Kirk lake.

West of Haileybury about three miles, an unconformity
is exposed between the Temiskaming and Cobalt series.
Here, at the southwest corner of lot 7, in the fourth con-
cession of Bucke. the Cobalt conglomerate rests on the up-
turned edges of the Temiskaming greywacke, the latter
showing distinct bedding. Xearby, the older series is cut
by lamprophyre dikes, which do not, however, invade the
Cobalt sediments. In the same neighborhood there are
several places where the two series are separated only by
a few feet of drift, but the discordance of the dips is so
striking that there can be little doubt about the existence of
the unconformity. At Fleming Corners the flat lying, slate-
like greywackes of the Cobalt series are in marked contrast
to the disturbed Temiskaming sediments one-half mile to
the east.

Boulders of conglomerate of the Temiskaming series are
found in the conglomerate of the Cobalt series, as shown in
the accompanying illustration.

The thickness of the Temiskaming series cannot now be
determined with certainty. In one locality it is known to
be at least 7,000 feet.

LAMPROPHYRE DIKES AND LORRA1N GRANITE

Xear Kirk lake, both lamprophyre and granite intrude
the Temiskaming series, and the lamprophyre is seen to be
older than the granite.

Lamprophyre dikes are numerous in the area. They
are, for the most part, characterized by the prominence of
hornblende, biotite or augite. The following types are
probably present, viz. : minette. kersantite, vogesite and
camptonite. The rocks vary in grain from fine to coarse, and
in width from a foot to twenty feet or more. While they are
somewhat disturbed, and in some cases much decomposed,
they are usually massive rather than schistose, and fre-
quently preserve their original textures.

The distribution of the Lorrain granite is shown on the
map of Cobalt, scale one mile to an inch. The rock is a

Temiskaming series, tilted into vertical position, between
Haileybury and New Liskeard.

coarse-grained, bictite granite, with a characteristic pink
color. At Kirk lake it invades the Keewatin greenstone, the
Keewatin iron formation (Grenville series), the Temiskam-
ing sediments and the lamprophyre dikes. Whether some
of the quartz and feldspar prophyries, described under the
Keewatin series, are genetically connected with the Lorrain
granite is not as yet known. The granite is overlain uncon-
formably by the Cobalt series. Its relative age is therefore
accurately known. Where it invades the adjacent form-
ations it sends out in every direction many fine-to-medium-
grained aplite dikes. In hand specimens these dikes are
similar to some of the aplites which are the end phase of the
Nipissing diabase. The latter dikes, however, contain only
small quantities of potash, while the granite aplites at Kirk
lake have normal percentages of soda and potash, as will be
seen from the analyses given below. The intrusion of the
Lorrain granite was probably the means whereby the Temis-
kaming sediments were tilted up into their present more or
less vertical position. Xear the contact the intrusion has
sometimes developed garnets in the adjacent rocks.

Analysis Xo. i, given below, is from the coarse-grained
parts of the granite, while Xo. 2 is from the aplite dikes a
few inches in diameter. In each case about a dozen speci-
mens were taken in order to arrive at average results.

1 2

Si02 71-86 76.03

Fed 2.34 1.29

Fe2Os 1.73 1-44

Al2Oo 1 5. 1 1 13.02

CaO° 51 -15

MgO 43 16

Na,0 370 3-68

K26 348 374

HoO 1.22 .96

100.38 100.47

While the Lorrain granite has been intruded by the
Xipissing diabase, silver-cobalt deposits of importance have
not been found in it. That silver is rapidly deposited on
the surfaces of or in cracks in the granite is shown by the

occurrence of this metal in veinlets which penetrate granite
boulders in the Cobalt series, in the vicinity of the veins at
the Coniagas and Trethewey mines. Certain dikes from
the granite penetrate the Keewatin in the lower workings of
the Temiskaming mine and are cut through by the vein.
The granite is here coated with silver.

In the township of Lorrain, to the east of Cobalt, much
of the granite presents a weathered surface, there being a
gradual transition from the undecomposed rock to the over-
lying sediments of the Cobalt series.

THE COBALT SERIES

The age relations of this series of fragmental rocks are
shown in the table on a preceding page.

Since eighty per cent, or more of the ore mined at
Cobalt has come from veins, or parts of veins, that are
found in this series, it is the most important, from an
economic point of view, of the rock groups of the area.
Hence the name given to it is appropriate. The series also
presents many other interesting features.

Erosion has left but remnants of this series, which in a
past age covered practically all the surface in a vast region
in Northern Ontario.

The series is wholly of fragmental origin, and contains
rocks varying from those that are uniformly fine in grain to
those that contain boulders several feet in diameter. The
kinds of fragments composing these rocks are almost in-
numerable, representing as they do the erosive products
from all the older pre-Cambrian series of the region —
Keewatin, Laurentian, Temiskaming, Lorrain granite and
intrusives of various ages. Naturally, fragments of the
harder rocks and minerals have withstood better the des-
tructive agencies to which thev have been subjected, and
the Cobalt series, especially the members of it that are
coarser in grain, contain grains of feldspar and quartz, and
pebbles and boulders of granite and other igneous repre-
sentatives, in greater numbers than thev do of minerals or
rocks that weather or are abraded more readily. But
representatives, as has already been said, of all the older
rocks in the region are to be found in the form of pebbles
or boulders as components of the Cobalt series.

Boulders Composed of Conglomerate.

From the description of the Temiskaming series, on a
preceding page, it will be seen that it, like the Cobalt series,
consists of fragmental rocks, ranging from greywackes fine
in grain to coarse conglomerates. Probably the most re-

Conglomerate of Cobalt series, containing- a conglomerate boulder
from the Temiskaming series.

markable boulders in the conglomerate of the Cobalt series
are those of conglomerate from the Temiskaming series. If
the latter series has furnished conglomerate boulders to the
former, undoubtedly it lias sunplied pebbles or boulders of
quartz and other minerals and rocks which once were con-
stituents of its conglomerates.

Order of Deposition.

The surface of the region, in the period immediately pre-
ceding the deposition of the Cobalt series, was uneven, and
possessed in all probability higher hills and deeper valleys
than those of the present surface. Having been laid down
on such an uneven floor, the series cannot be expected to
show the same thickness of sediments everywhere, even had
a great period of erosion not elapsed between the deposition
of the sediments and the present time. Moreover, it would
be expected that there would be a considerable variation in
the order of succession of the sediments from those that lie
at the base to those that form the upper members. While
such variation in the thickness of the members of the series,
and in their order of deposition, has been observed, as is
shown in the following table, still, there is a pronounced
definite order of deposition in the areas which have been
studied by various workers throughout a wide region.

The following table shows the thickness of the Cobalt
series at several characteristic localities, and the nature of
the sediments, together with the order of deposition :

Wend i go Lake

Little Silver
Cliff (Cobalt)

Mt. Chemaniss

Mt. Sinclair

Maple Mountain

Arkoseand quart-

Conglomerate*

Conglomerate

Conglomerate*

zite (900 ft.)

(30 to 40 ft.)

(100 ft.)

Greywacke* and

quartzite (26 ft.)

Quartzite

* * *

(15 ft.)

(135 ft.)

Quartzite (10 ft.)

* * *

Greywacke"

Greywacke*

Greywacke" (54 ft.)

(20 ft.)

(315 ft.)

(300 ft.)**

* * *

Conglomerate*

* * *

Total 90 ft.

70 ft.

550 ft.

300 ft.

900 ft.

*Thickness not given. **Greywacke* contains occasional beds of slate and quartzite.
***Base of section is not exposed.

The arkose and quartzite of Maple mountain are con-
sidered to represent the Lorrain or upper part of the Cobalt
series. This mountain contains the greatest thickness of
sediments known in the region.

The exposure on the shore of the bay, on the east side
of Lake Temiskaming, just south of Fabre wharf, may foe
cited as an example of a section where members of the
series are absent. Here the upper conglomerate lies
on the surface of the well-banded greywacke.

Underlying Surface.

In the vicinity of Cobalt, the Cobalt series rests, char-
acteristically, on a weathered surface of one or other of the
older series of rocks. Most commonlv the underlying series
is the Keewatin, as rocks of this age are more widespread
in the productive part of the area than are the other pre-
Cobalt series. No surface that has the appearance of
having been produced by glaciation is known beneath the
Cobalt series in the vicinity of Cobalt.

Where the rocks of the Cobalt series rest on the green-
stones or other easily decomposed members of the
Keewatin there is a gradual transition from the non-dis-
integrated rock upward into the distinctly fragmental
member of the Cobalt series. The disintegrated material
on the surface of the Keewatin has been recemented and
consolidated, or, in other words, recomposed. It is im-
possible at certain contacts, without the examination of thin
sections under the microscope, to distinguish the recom-
posed material from the underlying massive igneous rock.

Something the same may be said of the contact between
the upper members of the Cobalt series, the Lorrain arkose,
and the Lorrain granite. In the township from which
the name of these rocks is derived, arkose lies on the
weathered surface of the granite, there being a gradual
passage from the undecomposed rock upward into the
arkose.

At the base of the Cobalt series there is the recomposed
material described in the preceding paragraphs with,
typically, conglomerate or breccia, many of the frag-
ments of which can be seen to have originated in place. A
striking example of the origination in situ of such material
is to be seen on the shore of lake Temiskaming, on the
extreme north end of lot 15 in the first concession of the
township of Bucke, a couple of miles south of Haileybury.
Here, as the geological map, scale 1 mile to 1 inch, shows,
the Cobalt series forms a contact with the Keewatin. At
the contact the Keewatin consists of greenstone, or basalt,
and a dike of feldspar-porphyry. That the conglomerate
and breccia of the Cobalt series, here resting on the
Keewatin, has, for the most part at least, originated in situ
is shown by the fact that it contains fragments of various

sizes of the porphyry dike. These fragments range in form
from angular to sub-angular and rounded. Both the green-
stone and the porphyry, but more especially the latter, show
characteristic torsion cracks.

This contact and others in the district, between the
Cobalt series and the older rocks, have a striking resem-
blance to those which have been described as existing
between members of the pre-Cambrian, Torridonian and the
older Lewisian, of the Northwest Highlands of Scotland.
"The observer may climb one of these Archaean hills, follow-
ing the boundary line between the Lewisian rocks and the
younger formation, and note, step bv step, how the sub-
angular fragments of hornblende-schist that fell from the
pre-Torridonian crags are intercalated in the grits and sand-
stones, thus indicating the slow submergence of the old land-
surface beneath the waters of Torridonian time."*

" The basal breccias which often flank the buried mount-
ains are, as already explained, of the nature of scree
material. They consist of fragments of the local rocks
embedded in a sandstone matrix. The conglomerates, on
the other hand, are probably torrential deposits brought
down from a district very different in geological structure
from that of the area in which the Lewisian gneiss occurs. "f

Slate-like: GrEywacke.

Normally, the basal conglomerate and breccia pass grad-
ually upward into fine-grained, delicately banded, slate-like
greywacke. The components of the graywacke are so fine
in grain that they cannot be distinguished except by exam-
ination of thin sections under the microscope. When thus
examined, they are found to consist, for the most part, of
angular fragments of quartz and feldspar, which is usually
quite fresh and undecomposed. The feldspar consists of
orthoclase, microcline and the more acidic soda-lime
varieties. Grains of glassy volcanic rocks, and of iron ore
and other material, have also been observed. Chlorite and

*The Geological Structure of the North-West Highlands of Scotland,
p. 4. Memoir of the Geological Survey of Great Britain,
fldem, pp. 286-7.

other decomposition products are present. Under the mic-
roscope certain thin sections of the greywacke resemble
volcanic ash. It has not been proved, however, that there
was contemporaneous volcanic activity.

Typically, the slate-like greywacke has a greenish or
greyish color, but in certain localities the color of the rock
is distinctly reddish. The latter color is not found in the
greywacke of the productive part of the Cobalt area proper,
but reddish greywacke lies both to the west and to the east,
outcropping in the western half of Coleman township, near
Latchford on the Montreal river, and at two or three points
near the shores of lake Temiskaming.

The greywacke, like the other members of the Cobalt
series, lies usually in an almost horizontal position. Ripple
or wave marks are frequently seen on the surface of its
beds, e.g., in the cliff at the Little Silver mine on the
Nipissing property. Mud cracks have also been observed.
While usually showing little evidence of disturbance, the
greywacke is quite compact and does not split readily along
the junction of many of the beds.

Normally, the greywacke passes upwards into quartzite,
more or less impure, and the latter into conglomerate, but at
times the quartzite is lacking and the greywacke is suc-
ceeded by conglomerate. Where the members of the series
are complete, as at some points along the eastern shores of
lake Temiskaming, the conglomerate appears to be suc-
ceeded without unconformity by what has been called the
Lorrain arkose and quartzite, the latter of which is fre-
quently interbanded with pebbly material.

At two or three places, however, where the upper
members of the series, conglomerate or arkose, lie directly
on the greywacke, without the quartzite or other inter-
mediate member being present, the greywacke is seen to
have been eroded before the deposition of the overlying
rock.

Quartzite.

The quartzite usually has no great thickness, frequently
being only twenty or thirty feet, but in certain localities
impure quartzite or greywacke that overlies the delicately

banded greywacke has a much greater thickness, as shown
in the table on a preceding page.

At the Little Silver cliff, on the Nipissirig property, the
base of the Cobalt series is not exposed. Here there are
fifteen or twenty feet of well-banded greywacke, overlying
which there is about the same thickness of feldspathic
quartzite. Above the latter is twenty or thirty feet of con-
glomerate.

At times the quartzite is interbanded with greywacke

Conglomerate.

What may be called the second conglomerate, to dis-
tinguish it from the conglomerate and breccia that lie at the
base of the well-banded greywacke, or in other words the
conglomerate that overlies the quartzite, is one of the most
interesting members of the Cobalt series. The great variety
of pebbles and boulders that are found in this rock give to
it an appearance that attracts attention. It contains
boulders representing practically all of the numerous older
rocks of the region. Whether it represents a glacial deposit,
or whether it is of torrential or other origin, in the opinion
of many observers, is undecided.

The conglomerate of the Cobalt series is distinguished
from that of the Temiskaming series chiefly by the fact that
pebbles and boulders of pink granite, rather coarse in grain,
are characteristic of the former and not of the latter. This
is owing to the fact that the granites of the region, that
antedate the Temiskaming series, are typically grey in
color, while the pebbles and boulders in the conglomerate
of the Cobalt series have been derived from the pink-colored
Lorrain granite, which intruded the Temiskaming, but is
older than the Cobalt series. Moreover, the members of
the Temiskaming series dip at high angles while those of
the Cobalt series are usually but slightly inclined.

Origin oe the Conglomerate.

In the first edition of his report on the Cobalt area,
concerning the origin of the conglomerate the writer said :
" It is difficult to understand, for example, how certain

large boulders of granite in the conglomerate, which forms
part of the highest outcrops of the Lower Huronian
( Cobalt series), have been carried so far from their parent
masses. These large boulders are found over much of the
district, and there are now no outcrops of granite in the
neighborhood of many of them. ... In the present
state of our knowledge we have little warrant for claiming
that the granite boulders, often two or three feet or more
in diameter and distant a couple of miles from exposures
of the rock, indicate glacial conditions during Lower
Huronian times, although we have no proof to the
contrary."*

A couple of years after this report was published Dr.
A. P. Coleman, while on a visit to the Trethewey mine, dis-
covered striated boulders in the conglomerate in an outcrop
on this propertyt that have all the characteristics of those
which are found in glacial deposits. Hence. Dr. Coleman
and other writers have decided that a certain part, at least,
of the conglomerate of the Cobalt series is of glacial origin.

In the opinion of the present writer more evidence is
required before the glacial origin can be accepted. Although
for many years conglomerates similar to those of Cobalt
have been studied over a vast extent of territory in northern
Ontario, no glaciated surface on the rocks underlying this
conglomerate has been discovered. During the last few
years several workers in the Cobalt and surrounding areas
have diligently searched for such a surface, but without
success. The underlying rocks present, characteristically,
a weathered surface, there being no sharp line of division
between the underlying, undecomposed, or non-disintegrated,
rock and the overlying fragmental rock. The glacial origin
of the Cobalt conglomerate cannot therefore be proved so
clearly as it can for similar rocks in other parts of the
world. The Dwyka of South Africa, for example, rests on
rocks that frequently show undoubted evidence of having
been smoothed by glaciers. Opportunities for observing
contacts at Cobalt are. however, being constantly enlarged

*Fourteenth Report. Bureau of Mines. Ontario, Part II.. pa°re -43.
+Am. Jr. Se'enee, March, 1907. Journal of Geology, February -
March. 190S.

by stripping the surface in prospecting, and it is possible
that the Cobalt series may be found to rest on a surface of a
different character from those at present known.

A glacial origin was at one time suggested for certain
breccias or conglomerates in the Torridonian of the North-
western Highlands of Scotland. In the report on that
region, published a few years ago, this suggested theory of
origin has been discarded/11 " From the nature of the rocks
it may be inferred that the conditions of deposit were prob-
ably those of a rapid accumulation in shallow water near a
shore line, subject to violent currents and the influx of flood
or stream-borne materials, with occasional intervals of
quiescence during which the finer sediments were laid
down. ... In one instance, on the north side of Loch
Maree, it has been observed that the blocks in the con-
glomerate have come from the hornblende-schist ridge of
Ben Lair, and may have travelled a distance of three
miles."

That surfaces on rocks resembling closely those pro-
duced by glaciers can be formed by other means is shown by
the observations of Dr. E. O. Hovey.* In speaking of
the accumulation of volcanic material on the side of Mt.
Pelee, he says : "From time to time the coat of new material
became water-soaked from the heavy tropical rains and slid
down the mountain in more or less of a sheet avalanche. On
the collecting ground of the steep upper cone, planation and
grooving were not prominent, but on the middle ground of
the Morne Saint Martin, where the force of the avalanches
spent itself, planation and grooving were pronounced. In
June, 1902, the striated surface of the old agglomerate, with
here and there a heap of unassorted ash upon it, suggested
closely the appearance of a regularly glaciated surface with
its overburden of till."

Dr. Hovey says further : " Where the crevicing of the
rock-mass has been favorable, the impact of stones hurtling
down the stream bed has broken off chips from the bed
rock, producing a good imitation of the ' chatter ' marks
made by a glacier."

*The Geological Structure of the North-West Highlands of Scotland,
pp. 23 and 273. Memoirs of the Geological Survey of Great Britain, 1907.

*Striations, U-shaped valleys, and hanging valleys produced by other
than glacial action. Geol. Soc. Am., Vol. 20.

If such surfaces are thus produced, undoubtedly the
faces of pebbles and boulders in moving masses of rock are
also grooved and striated in such a way as to be undis-
tinguishable from those of glacial origin.

Lorrain Arkose; and Quartzite.

As explained on a preceding page the arkose and quartz-
ite, to which the name Lorrain has been applied, are here
grouped with the Cobalt series, and are considered to
represent the upper members of the series. In two or three
localities, the arkose and quartzite have been found to be un-
conformable to the slate-like greywacke or other lower
members of the series, but in other places there is no evi-
dence of an erosion interval. Since, however, the arkose
and quartzite in most of the areas that have been mapped
tend to occur distinct from the lower members of the series
they are distinguished on the maps, by a different color,
from the latter.

Frequently the arkose is found on the surface of granite,
e.g., in the township of Lorrain, and is the decomposition
product of the latter rock, there being a gradual passage
from the undecomposed rock into the arkose. There is.
moreover, a gradual passage upward from the arkose, first
into impure quartzite, then into a purer quartzite and con-
glomerate, composed chiefly of quartz pebbles.

THE NIPISSING DIABASE

The diabase, to which the name Xipissing has been
given, occurs characteristically as a sill. At Cobalt much
of the hanging wall of the sill has been removed by erosion,
and the diabase occupies about one-half of the surface of
the productive area, the sill dipping on the whole at a low
angle to the southeast. From following descriptions, how-
ever, it will be seen that the din of the sill is much steeper
at certain points.

In the region 5,000 square miles or more in extent, that
surrounds Cobalt, the diabase occupies a considerable
percentage of the area, and is seen in many cases to be in
sill-like form. Owing to the association of cobalt ores with

The position of Sections is shown on the map of COBALT, scale 800 feet

to an inch.

PLATE H

DIABASE

MOU NTA I N

Savage

' / /

Glen Lake

^ ^ x\\ I - v - ! tX X " v J c f S;f

"\ ^ \l 1 N/ \ / s

SECTION G H

EAST

BOO Ft.

HORIZONTAL AND VERTICAL SCALE
800 feet clinch

K E E W ATI N

tiV^'li COBALT SERIES

"V/Jrl NIPISSING DIABASE

To accompany Fourth, Edition of Report by WILLET G.MILLER, Provincial Geologist, on the Cob alt Nickel Arserudes and Silver Deposits of ' Temiskamirtcj

In Part 11. of the Nineteenth Report of the Bureau- of Mines, Ontario

Hie position of Section is shown on t/te map of COBALT, scale 800 feet to an inch.

PLATE JF

WEST NORTHWEST

S ECTION

Y Z

EAST SOUTHEAST

o +00 BOO Ft.
1 1 1 1 — 1 — 1 1 1 '

HORIZONTAL AND VERTICAL SCALE

800 feet =i inch.

1^-^/1 K EE WAT IN

COBALT SERIES

IVVV/d Nl PISSING DIABASE

To accompany Fourth. Edition of Report by WLLLET G.MILLER, Provincial Geologist, on tlve Cobalt Nickel Arseiudes and Silver Deposits ofTemiskaniing

In, Part II. of the Nineteenth Report of the Bureau, of Mines, Ontario

this diabase in numerous localities throughout this region,
the diabase and the ores are believed to have come from the
same magma.

Nearly all varieties of the rocks forming the sill at
Cobalt, when examined in thin sections, are found to have
an ophitic texture, and primary quartz is almost always
present. The rock is, therefore, a quartz-diabase. Most
of the quartz is associated with feldspar in micrographic
intergrowth.

The chemical composition of certain typical specimens of
the quartz-diabase of the Cobalt area, and its relation to the
quartz-norite of Sudbury are shown in a following table.

The thickness of the diabase sill at Cobalt is five or six
hundred feet or more. In diamond drilling, at one point
near the shore of Cross lake, the thickness was found to be
nearly twice as great, but this is believed to be due to fault-
ing. Cross lake lies in line with Kirk, Chown and Goodwin
lakes, the chain of lakes probably indicating the direction
followed by a fault.

The accompanying generalized section shows the re-
lation of the diabase sill to the Keewatin and the Cobalt
series, and to the veins, in the Cobalt area. Cross-sections
of the area published by the Ontario Bureau of Mines give
more details, as the following notes on the general section
of the area show. The " Map of Cobalt Area," scale 800
feet to 1 inch, that accompanies this guide book, shows the
location of the sections.

General Section, Upper Hat.p op Plate IV.

The section incorporates much of the information con-
tained in other sections, together with additional data. Its
total length is about 4^ miles, and it may be added that
the bottom line represents sea level. The cross-section
begins at the southeast corner of Sasaginaga lake, and
shows the important area of conglomerate, greywacke, etc.,
of the Cobalt series, resting in an ancient valley of the
Keewatin series, between Cobalt and Sasaginaga lakes. A
reverse fault — normal to the line of section — occurs parallel
to the longer axis of Cobalt lake, and it is also found at the
McKinley-Darragh about one-quarter of a mile to the south-
west, and at La Rose at the north end of the lake.

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At La Rose mine the rocks en the west side of the fault
have been carried down a vertical distance of 210 or 220
feet, and at the McKinley-Darragh a vertical distance of at
least 250 feet.

The diabase at the Little Xipissing dips S. E. at an
angle of 16 degrees, while at the Crown Reserve it has been
proved to dip more steeply at angles varying from 17 to 45
or 50 degrees to the N.W., from which it appears that the
sill occupies a basin-like depression in the underlying rocks
between these two properties.

If the Kerr lake area be now studied it will be found
that the diabase inclines steeply to the N.W. and to the S.E.
of the axis of the lake, forming a saddle-like structure. It
may be seen dipping to the N.W. at the following points:
the southwest shore of Cross lake; the northeast corner of
the north Drummond lot ; about 200 yards east of Kerr lake
and 25 yards north of the road (a diamond drill hole near
here has also proved the dip to be northerly) ; a trench on
the Silver Leaf has exposed the contact of the diabase for
about fifty yards or more. On the south flank of this
saddle-like structure the diabase lias been proved to dip
S.E. at the following points: the Valentine shaft; a
vertical diamond drill hole on the south part of the south
Drummond lot ; shaft No. 5 of the Drummond mine ; shaft
No. 1 of the Hargrave ; two drifts from the No. 3 shaft of
the Kerr lake; a drift from the 369-foot level of the No. 3
shaft of the Hargrave. From the above data it is thus seen
that the saddle-like structure of the diabase at Kerr lake has
been proved at several points. But it may be added that
some of the steep inclinations of the sill may be partly due
to faulting. There is, for example, a well defined fault in
the diabase at the Crown Reserve, 540 feet north of the shaft
in the drift at the first level, dipping- 15 or 20 degrees to
the north. Again on the south side of the saddle-like
structure a fault, dipping to the southeast, was encountered
at the Hargraves and Drummond.

At the Lumsden a shaft was sunk in the Keewatin to a
depth of 290 feet, where it passed into the Nioissing diabase,
proving that the sill here dips beneath the Keewatin green-
stones at an angle of about 26 degrees. Similar relations
are known to obtain at other points along the same contact
to the southwest as far as Mount Greywacke

Coming, finally, to the Temiskaming mine it is found
that the diabase has been encountered on the fourth and
fifth levels., and at a depth of 575 feet in the main shaft.
The surveys show that the sill dips at angles varying from
17 to 30 or 40 degrees in different parts of the mine, but it
is probable that faulting may have caused some of the
steeper inclinations, because a vertical fault between the
diabase and Keewatin is known to occur on the fourth level.
There are, however, no data at present to determine the
throw of this fault.

Quartz-diabase, Cobalt, showing- labradorite, P, embedded in a micro-
graphic intergrowth of quartz and feldspar.

Facias of the Diabase.

While, as will be seen from the preceding descriptions,
the diabase in the productive part of the Cobalt area is fairly
uniform in character, differentiation is found in the outlying
areas. Thus, a few miles to the west and also to the south
of Cobalt pink spots, areas of micropegmatite, appear in the
diabase. In certain localities these oink spots increase
until the rock becomes pink or reddish, and is then more
correctly described as granophyre than as diabase. A
similar, but more complete, change, from a basic, darker
rock to a lighter colored, more acidic variety, is found in
the norite of Sudbury.

§5

At times the typical diabase passes into a rock much
coarser in grain, that has been described as gabbro, but
many of these coarser varieties, when examined closely, are
found to have the ophitic texture.

DIKES OF APLITE OR GRANOPHYRE YOUNGER THAN NIPISSING DIABASE

Especially in the Elk lake and Gowganda areas
the Nipissing diabase is frequently cut by narrow dikes of
aplite or granophyre. The material in these dikes is believed
to represent residual, more acid material of the diabase
magma. On the cooling of the diabase, cracks were formed
in it, and material from the residual magma, rising through
the cracks and fissures, formed the dikes of aplite or
granophyre. Chemical and microscopical examinations of
these dike rocks show that they are genetically connected
with the diabase rather than with granite. Compared with
the fine-grained granite or felsite dikes in the region, such
as those connected with the Lorrain granite, the aplite dikes
associated with the Nipissing diabase are found to be char-
acteristically high in soda and low in potash, as following
analyses show.

At Cobalt there is a dike of granite on the property of
the University mine that cuts the Nipissing diabase and
from its chemical composition is seen to be related to the
aplites of Gowganda and Elk Lake. Having a much
greater width than have the characteristic dikes elsewhere
in the region, it is naturally coarser in grain. An analysis
of samples from this dike is given below.

Examined in thin sections under the microscope, the dike
rock at the University mine is found to be made up of
feldspar, quartz and a colored constituent. The feldspar
predominates, and consists of microcline and an acid
plagioclase showing fine albite twinning lamellae. The
quartz and feldspar occur in allotriomorphic grains, but in
two instances show distinct micrographic intergrowths. The
colored constituent is not abundant ; it was apparentlv
originally a mica, but is now represented by chloritic
material.

This dike averages fifty feet in width, while the dikes of
the Montreal river area and Gowganda are usually under
eighteen inches.

Analyses of the Acid or Granophyric Facies of the Eruptives

III

SiOo

7?. 33

62.54

61.93

67.76

76.03

A1203

12.99

14.79

13.03

14.00

13.02

0.00

0.56

0.00

1.44

FeO

2.50

8.49

8.00

5.18

1.29

MgO

0.97

2.08

1.76

1.00

0.16

CaO

1.73

1.49

4.02

4.28

0.15

7.60

6.27

3.18

5.22

3.68

0.00

1.12

2.80

1.19

3.74

H20

1.09

3.51

1.95

1.01

0.96

TiO-2

0.74

0.00

0.84

0.46

0.00

0.32

0.19

0.00

0.18

trace

0.00

C02

1.00

0.00

0.19

0.00

100.95

100.29

98.76

100.29

100.47

I. University mine dike, Cobalt, N. L. Bowen, analyst (Journal Can. Min. 1st., Vol XII).

II. Lost Lake granophyre, Gowganda Cobalt-Silver area, N\ L. Bowen, analyst,

III. Acid edge of nickel eruptive Onaping section, Sudbury, E. G. R. Ardagh. analyst.

IV. Near acid edge of the Blezard-Whitson lake section. Sudbury, T. L. Walker analyst.
V. Lorrain granite dikes, fine in grain or aplitic, Cobalt. About a dozen specimens were

taken to get an average.

Analysis No. V is added to the table to show the difference in composition between the
•dikes of Lorrain granite and the acid facies of the Nipissing diabase and Sudbury norite. In
all the analyses of the latter the proportion of soda to potash is high while in the case of the
Lorrain granite dikes it is more nearly equal.

BASIC DIKES YOUNGER THAN NIPISSING DIABASE

In the region one hundred miles in width, between
Sudbury on the southwest and Quinze lake, which lies to
the east of the head of Lake Temiskaming, on the north-
east, basic dikes have been found at many points. These
dikes are younger than the Sudbury norite and the Xipissing
diabase, which, of the basic igneous rocks, immediately
precede them in age.

The age relation of these dikes to those of aplite or
granophyre, described in a preceding paragraph, which are
believed to represent acidic, residual material of the
Nipissing diabase magma, is not known. The basic dikes
in all probability also came from this magma. In the
Sudbury area these dikes are cut by greyish, fine-grained
granite, the youngest intrusive of that area.*

*14th Report, Ontario Bureau of Mines, Part III., pp. 14, 12P.

At Sudbury the basic dikes are composed of olivine
diabase which on weathering shows the characteristic
spheroidal forms. In thin sections under the microscope
the rock is one of the most beautiful of its class. Similar
dikes of olivine diabase on the Quinze river, a hundred
miles to the northeast of Sudbury, have been described by
the writer*

In the region between Sudbury and the Quinze many
dikes of olivine diabase have been found as well as those of
olivine-free diabase.

In the vicinity of Cobalt these dikes are rare, the only
one studied by the writer being the basalt-diabase of Cross
lake.

Analyses.

The following table shows the chemical composition of
two typical samples of the Nipissing diabase at Cobalt, and
that of a rather basic type of the Sudbury norite, together
with analyses of two later basic dikes.

No. 1.

No. 2.

No. 3.

No. 4.

No. 5.

45.20

47.22
3.62
16.52
3.32
12.40
9.61
3.33
.01
3.40
.67
.04
trace
.0275
.0055
.33
.30

49.84

48.06

49.90
1.47
16.32

Alo03

19.08
3.64

14.64
7.89
4.98

18.94
1.51 )
6.40 J

10.32
7.39

18.23

9.57

11.55
7.80

Fe203

FeO

13.54
6.58
6.22

CaO

MgO

BaO

NaoO

3.32
1.08

1.99
1.28

■

1.87
.27

i.82
2.25
trace

K20

MnO

CuO

::::::::::::

TCiO

CoO

P2O5

.17
.76

H20

2.57

3.54

Total

9tf. 83

100.803
3.01

100.24

100.89

99.03

No. 1, basalt-diabase dike, Cross lake, Cobalt. No 2,
olivine diabase dike, Sudbury. No. 3, Nipissing diabase
cut by basalt-diabase dike at Cross lake. No. 4, Nipissing
diabase, on the Violet property near Cross lake. No. 5,
norite, more basic than the average, at Sudbury.f

*llth Report, Ontario Bureau of Mines, pp. 227, 229.
fAnalyses Nos. 2 and 5 are taken from Dr. A. P. Coleman's paper in
the Fourteenth Report, Ontario Bureau of Mines, Part III.

PALEOZOIC

It will be seen from the map, scale I mile to the inch,
that the Niagara and Clinton limestone forms some large
outcrops on the islands and in the vicinity of the
shore near the northwest corner of lake Temiskam-
ing. This limestone affords stone suitable for build-
ing and for the production of lime, and on this account
should be of considerable value in the years to come, since
the rock is a somewhat rare material in most of this northern
part of Ontario. The district to the west and north is being
rapidly settled and will soon contain a large population
which will need much material for building purposes. The
following is an analysis of a sample of limestone taken from
Farr's quarry, Haileybury:

Per cent.

Insoluble residue 1. 60

Ferric oxide and alumina .66

Lime 29.50

Magnesia 21.59

Carbon dioxide 46.84

Sulphur trioxide .70

100.89

This limestone formation extends northward, although
overlain by clay and similar deposits in many places, and has
been observed by the writer along the south branch of the
Blanche river below what is known as the Mountain
portage.

Considerable attention has been paid to the limestone
area, Sir William Logan having first described it years ago.
It has been shown that the series here is more closelv related
to the Niagara of Southern Ontario than it is to the Niagara
areas to the north and west.

The cobalt-silver deposits being of pre-Cambrian age, the
Paleozoic limestone is of little interest in connection with
the ores. It is of course possible that ore-bearing rocks
underlie the limestone.

Along the wagon road, in lots 5 and 6 in the third con-
cession of the township of Dymond, to the northwest of the
town of New Liskeard, the limestone cliff presents a striking

face, indicating faulting. The fault line is continuous with
the western shore of lake Temiskaming, and furnishes still
further evidence confirmatory of the theory that the lake lies
along a great northwest-southeast fault.

In places these limestones are rich in fossils.*

PLEISTOCENE

Immediately preceding the Glacial period, doubtless the
surface of what is now the productive cobalt-silver area
was in a highly weathered or decomposed condition. The
glaciers scraped off the loose material from the surface
and carried it southward, intermingled with other material.
In all probability much more cobalt-silver ore was carried
away by the ice sheet than has been mined. Nuggets or
boulders of rich silver ore have been found in prospecting
trenches at numerous points to the south of the mines. A
glacial boulder, worth about five thousand dollars, is now
in the Bureau of Mines collection.

Everywhere throughout the region the surfaces of the
rocks give evidence of glacial action. The underlying
loose deposits, on the surface of the glaciated rocks, consist
typically of boulder clay. This is succeeded upward, north
of Cobalt, by a considerable thickness of strikingly well
laminated clay. Above this clay, on some of the hills, to
the north of lake Temiskaming are sand and gravel deposits.
The glacial deposits in this part of Ontario have been well
described by Dr. A. P. Coleman.**

A couple of miles northward of Cobalt station the agri-
cultural region of this part of northern Ontario is met with.
The soil is essentially a well banded clay. Between this
point and the height of land, or watershed, between the
Hudson bay and Ottawa river waters, the clay does not
form a continuous mantle, but there are large areas of till-
able land which is being rapidly settled. Outcrops of solid
rock, in many cases representing hill tops, which project
through the clays, are seen. North of the height of land,
however, is a large agricultural area, estimated at 16,000,000

*Geol. Sur. Canada, Vol. X. 1897.
**Lake Ojibway; Last of the Great Glacial Lakes. Eighteenth Report,
Ontario Bureau of Mines, p. 284 et seq.

acres, now traversed by the National Transcontinental Rail-
way, and known as the " great clay belt," in which exposures
of solid rock are few in number. The clay on both sides of
the height of land is pretty uniform in character.

Following is an analysis of the clay in a cut on the
railway between Haileybury and Xew Liskeard. It will
be seen that the lime and magnesia are rather high. This
is owing to alternate bands containing considerable marl.
The clay effervesces strongly in acid.

Per cent.

Silica 52.00

Alumina 16. 1 1

Ferric oxide 4.69

Lime 8.26

Magnesia 4.10

Potash 1.74

Soda 2.76

Sulphur trioxide .09

Loss on ignition 9.64

Total 99-39

THE COBALT-SILVER VEINS.

The cobalt-silver veins occupy narrow, practically
vertical fissures or joint-like cracks in rocks of three ages,
viz. : Cobalt series, Keewatin series and Xipissing diabase.
The relations of the veins to each of these three groups of
rocks are shown in the accompanying generalized cross-
section of the Cobalt area and in the larger scale, colored
cross-section, (plate IV), published by the Ontario Bureau
of Mines. The veins are much more numerous in the rocks
of the Cobalt series than in the Keewatin or Xipissing
diabase.

It was estimated that up to July 1st. 191 1. the yield from
the XTipissing diabase had been approximately 7.55 million
ounces from 12 veins, or 629.000 per vein, or 7 per cent, of
the total production. The Keewatin with 13 veins had pro-
duced 1 1.7 million ounces, or nearly 1 million per vein, or
10.85 per cent, of the total. From 86 veins in the Cobalt
series there had been obtained 88.55 million ounces, or a

little over I million ounces per vein, representing 82 per
cent, of the total production. It is difficult to determine
the exact number of productive veins owing to the fact
that, being very narrow, parts of one vein may be mis-
taken for two or more distinct veins. At the present time
there are 115 or more productive veins, and the relative
productivity of those in the three series of rocks is about
the same as it was in 191 1.

A typical silver-cobalt vein, outcrop on Coniagas, Cobalt. The head
of the hammer shows the width.

ORIGIN OF THE VEINS.

After the intrusion of the Nipissing diabase sill,
which, on the whole, dips at a low angle from the horizontal,
and pentrates both the Cobalt series and the Keewatin,
disturbance, probably due chiefly to the contraction of the
sill on cooling, caused fissures and joint-like cracks to be
formed. These openings were made in the rocks of the
hanging-wall of the sill, in those of the foot-wall, and in
the sill itself.

Ore-bearing waters working through or along the zone
of weakness produced by the sill deposited their burden in
the fissures and cracks. The minerals first to be deoosited
were essentially cobalt-nickel arsenides, and related com-
pounds, and dolomite or pink spar. The fissures and cracks

were ultimately rilled with these minerals. Then there
was a slight disturbance of the veins, reopening the ore-
filled fissures and cracks, or facturing the material deposited
in them.

In the interval, between the filling of the fissures and
cracks with cobalt-nickel ores and the fracturing of the
veins thus formed by a secondary disturbance, the char-
acter of the material carried by the circulating waters had
changed. Silver was then the characteristic metal in
solution and it was deposited, along with calcite, in the

Polished surface of silver ore, slightly magnified, from La Rose
mine, Cobalt. The native silver, S, is the white material in
the illustration. The large black patches are calcite, the small
black spots niccolite, and the grey is smaltite.

cracks and openings in the fractured veins. There may
have been some silver deposited in the earlier period of vein
filling and doubtless cobalt-nickel minerals were deposited
after the secondary disturbance, but the latter minerals
belong characteristically to the first generation and the
silver minerals to the second.

Certain writers on the Cobalt ores have expressed the
opinion that the silver represents " secondary enrichment."
meaning that it has come from the decomposition of com-

pounds of the metal in the veins that were deposited at
approximately the same time as the cobalt-nickel minerals.
The present writer believes that at least by far the greater
part of ithe native silver is of primary origin. The recent
interesting experiments of Messrs. Chase Palmer and
Edson S. Bastin,* on the precipitation of silver from solu-
tions by cobalt-nickel minerals, appear to confirm the
opinion that the native silver is a primary deposit, and did
not come from the decomposition of silver compounds in
the veins. The work of these gentlemen shows that where
silver solutions come in contact with cobalt-nickel minerals
the silver is deposited rapidly and essentially as native silver.
Since there is much calcite in the veins with the native
silver, it would appear that the metal was carried in solution
as a carbonate, or double carbonate. Under ordinary con-
ditions of temperature and pressure, silver carbonate is
slightly soluble in water. For example, sufficient of the
carbonate can be dissolved in an ordinary beaker of water
to make a distinct precipitate of metallic silver when cobalt-
nickel minerals are placed in the beaker.

It has been proved, by the experience gained in mining
at Cobalt, that the presence of rich silver ore is dependent
on proximity to the diabase sill. Over much of the pro-
ductive area, not only the upoer wall of the sill but the sill
itself and more or less of its foot-wall have been removed
by erosive agencies. Owing to little of the ur>oer or hang-
ing wall remaining in the productive area, most of the ore
has come from the foot-wall of the sill, or from what was
the foot-wall before erosion took place. In these veins, in
the foot-wall of the sill, it is the exception to find rich silver
ore extending more than two or three hundred feet below
the surface. Most veins are productive to a lesser depth.
After rich silver ore disappears, with increase in depth,
cobalt-nickel ore frequently continues downward in the veins.
This seems to be due chiefly to the strong precipitating
effects that the cobalt-nickel minerals had on the silver in
the waters that worked downward beneath or along the sill.
The silver was deposited before it reached a great depth.
In certain cases, where veins with cobalt-nickel minerals
contain no rich silver ore, or in which the silver extends to

*Ec. Geology, March, 1913.

a comparatively shallow depth, the absence of the pre-
cious metal is to be accounted for by the fact that such
veins, or parts of veins, escaped fracturing during the
secondary disturbance, thus not affording openings for
deposition from the silver-bearing solutions.

Frequently, below the rich silver-bearing parts of veins
well crystallized argentite and hair silver are found in
vugs. These minerals may represent secondarv deposition

An underground view in La Rose mine, Cobalt, showing parallel

veins.

of a little of the silver that has been dissolved from the
upper part of the veins and carried downward.

Characteristically, the native silver of the area is im-
pure, chiefly from the presence of antimony and mercury.
Samples of well crystallized silver and certain veinlets of
the mineral that have been examined are free from these im-
purities. Such silver is probably of secondary origin.

When native silver is precipitated by its solutions coming
in contact with cobalt-nickel minerals, compounds of nickel

and other metals go into solution. Hence, it is not sur-
prising to find in the Cobalt veins minerals or compounds
of the baser metals that appear to have been deposited
during the later period of vein filling.

FORMER VERTICAL EXTENSION OF VEINS.

Certain writers have expressed the opinion that veins of
the Cobalt area, that outcrop at the surface or occur im-
mediately below the drift covering, represent the narrower,
lower parts of wider veins that extended to or towards the
original surface. There is no justification for the holding
of such an opinion. The few veins that have been worked
to a depth of a few hundred feet in rock of one series give
no indication of becoming narrower below, although, when
the veins are in the foot wall of the sill, the ore tends to
become less rich as the vertical distance below the sill or
the eroded part of it becomes greater. Moreover, "blind"
veins, or those which do not reach the present surface of
the rock, have been found. These veins have the same
character, as regards width and mineral content, as those
which are exposed at the surface.

Briefly, it appears that after the intrusion of the diabase,
fissures and cracks were formed in the rocks of the hanging-
wall and in those of its foot-wall, and in the sill itself. The
openings in the upper wall probably extended a considerable
distance upward beyond the sill, but there is no evidence
that they reached the surface or that they were wider in
the parts that have been eroded.

Some of these fissures in the upper wall extended down-
ward into the sill itself, e.g., veins on the Temiskaming,
Beaver, and Nova Scotia. The veins on these properties,
worked at the surface in the Keewatin hanging-wall, and in
the diabase sill below, are the deepest mines in the area.
No foot-wall vein has been found to be nroductive to such
a depth.

Then there are veins, e.g., that on the Cobalt Central
property, which have been wrorked at the surface in the
diabase and followed downward into conglomerate and
greywacke which at times lie beneath the sill.

Again, blind veins are found in the Cobalt series and in
the Keewatin where the sill has been eroded.

There are also blind veins, e.g.. one that was worked two
or three years ago under Peterson lake and one on the Silver
Leaf property, that lie in Keewatin beneath the sill. These
veins run upward to the lower face of the sill but not into it.

The types of veins mentioned in the preceding para-
graphs are shown in the accompanying, generalized cross-
section of the area.

RELATION OF WALL ROCK TO ORE.

The productive veins, as the maps and cross-sections
show, are found in three series of rocks, viz. : the conglom-
erate and other sediments of the Cobalt series, the Xipissing
diabase sill, and the Keewatin complex. But eighty per
cent, or more of the ore has come from the Cobalt series.
The chief reason for this greater productiveness is due to
the fact that these rocks fractured more readily than did the
diabase or the Keewatin.

There appears to have been no difference in the pre-
cipitation of ores due to physical-chemical influences of the
country rocks. Precipitation seems to have taken place as
readily in rocks of any one of the three series mentioned in
the preceding paragraph as in the others.

Judging from the way in which silver is found in the
minutest cracks in granite boulders of some of the con-
glomerate near the veins, this ore, at least, was precipitated
no less readily in acidic rocks than in basic ones. With the
exception of these boulders, there are few opportunities
afforded of observing the relations of the ore to granite.
But in the Temiskaming mine, a few hundred feet below the
surface, narrow dikes of Lorrain granite intrude the
Keewatin and are cut across by a vein. The surface of the
granite is plated with native silver.

The occurrence of rich silver ore depends on the char-
acter of the openings in the rocks now occupied by
the veins, on whether the veins have been affected
by secondary disturbances, and on the proximity of
the openings to the diabase sill. Xaturallv it would
be expected that solutions would work upward through
the openings in the hanging wall above the sill more
readily than downward into the foot wall. Unfortun-
ately owing to the excessive erosions to which the district

has been subjected, there is little of the hanging wall of the
sill left in the productive area at Cobalt. But of the veins
thus far worked the two or three that occur in the hang-
ing wall are productive to the greatest depth reached in the
area.

In the foot wall of the sill, or what was the foot wall
before erosion took place, the rich or merchantable ore is
limited as to the depth to which it extends. This depth
below the sill is variable, depending on the character and
strength of the fissures, and other factors already mentioned.
Rich ore descends to a less depth in narrow more irregular
fissures than in wide ones.

As has been said previously, much the greater part of
the ore has come from veins in the fragmental rocks of the
Cobalt series in the foot-wall of the sill. These veins, on
reaching the contact of the Cobalt series with the underlying
Keewatin, either end at the contact, or split into stringers,
or continue down into the Keewatin. In many cases the
rich ore disappears when the veins penetrate the Keewatin.
On the other hand, a few veins in stronger fissures have
been found to be productive in the Keewatin, that, before
erosion, lay beneath the sill.

In the veins both in the diabase and Keewatin rocks, ore
is found to occur more irregularly distributed than in those
of the Cobalt series. In other words, it tends to occur in
bunches.

The best veins that have been worked in the diabase are
one on the Kerr lake property and one on the O'Brien. Of
those in the foot-wall of the sill, the best vein in the
Keewatin has been No. 26 on the Nipissing.

ORES AND MINERALS.

The more important ores in the veins under consider-
ation are native silver — associated with which is usually
some dyscrasite, argentite, pyrargyrite and other compounds
of the metal — smaltite, niccolite and related minerals.
Many of the minerals occur mixed in the ores, and for this
reason some of them have not been clearly identified.
Another character of the minerals, which renders their
identification difficult, is the fact that most of them occur
in the massive form. Crystals when present are small,
being frequently almost microscopic in size. The following
minerals have been identified and can be conveniently
classed under the headings :

7—7

I. — -Native Elements :

Native silver, native bismuth, graphite.
II. — Arsenides :

Niccolite, or arsenide of nickel, NiAs; chloan-
thite, or diarsenide of nickel, NiAs2 ; smaltite,
or diarsenide of cobalt, CoAs2.

III. — Arsenates :

Erythrite, or cobalt bloom, Co3As208+8H20 ;
and annabergite, or nickel bloom, Ni3As208+
8H20 ; scorodite, FeAs04+2H20.

IV. — Sulphides :

Argentite, or silver sulphide, Ag2S ; millerite, or
nickel sulphide, NiS ; argyropyrite ? strom-
eyerite? (Ag, Cu)2S; bornite, Cu5FeS4; chal-
copyrite, CuFeS2 ; sphalerite, ZnS ; galena,
PbS ; pyrite, FeS2.
V. — Sulpharsenides :

Mispickel, or sulph-arsenide of iron, FeAsS ;
cobaltite, or sulph-arsenide of cobalt, Co/VsS.
VI. — Sulpharsenites :

Proustite, or light red silver ore, Ag3AsS3 ;
xanthoconite ? Ag3AsS4.
VII. — Antimonides :

Dyscrasite, or silver antimonide, Ag„Sb ; breith-
auptite, NiSb.
VIII. — Sulphantimonites :

Pyrargyrite, or dark red silver ore, Ag3 SbS3 ;
stephanite, Ag5 SbS4 ; polybasite ? Ag9 SbS6 ;
tetrahedrite, or sulph-antimonite of copper,
CusSb2S7 ; freibergite? (silver-bearing tetra-
hedrite).
IX. — Sulphobismuthites :

Matildite, AgBiS2 ; emplectite, CuBiS2.
X. — Mercury :

Amalgam ?
XI. — Phosphate :
Apatite.
XII.— Oxides :

Asbolite ; heubachite ? ; heterogenite ? : arsenolite ;
roselite ?
XIII. — Veinstones :

Calcite, dolomite, aragonite, quartz, barite.
fluorite.

The table contains a few minerals that have been found
in only one or two veins and cannot be considered char-
acteristic. Millerite, for instance, is of rare occurrence,
and emplectite has been found only in the Floyd mine, near
Sharp lake, in the western part of the Cobalt area. Bornite,
chalcopyrite, zinc blende, galena and pyrite are not char-
acteristic of most of the ore, these minerals occurring more
frequently in the wall rock or in non-silver bearing ore of
the Keewatin, but one or two mines have produced copper
with cobalt-silver ore. Apatite in recognizable crystals has
been found in the ore of only one mine. Mercury appears
to occur in the ore of all the mines that contain high values
in silver, but whether it occurs only as amalgam or in other
forms has not been determined. Among the veinstones,
aragonite is found but rarely, at least in easily recognizable
form, while barite and fluorite have not been observed in
the veins at Cobalt proper.

A question mark has been placed after the names of
several minerals in the table which have been reported to
occur in the veins but the identification of which has not
been made complete by chemical analyses or crystallographic
measurements.

Gold in small quantity has been found in a number of
veins, especially in those in which cobaltite or mispickel are
characteristic minerals.

A characteristic of the group is the subordinate part
which sulphur plays in comparison with arsenic. Antimony,
which is not abundant, is found in some compounds where
one would expect to find arsenic, since the latter is so much
more abundant. For instance, while both native silver and
arsenides occur in abundance, the compounds of arsenic and
silver are found only in small quantity. Then one would
also expect to find more compounds of bismuth since this
metal occurs in the free state in considerable quantities in
some parts of the deposits. It might also be expected that
native arsenic would occur at times.

Nearly all the chemical groups of minerals found in the
celebrated Joachimsthal deposits of Bohemia are present in
the TemiskaminQf ores. The most important exception is
uraninite or pitchblende, which came into prominence a few
years ago on account of its being the chief source of the
element radium.

IOO

ORDER Ol< DEPOSITION OF MINERALS.

The following table shows, in descending order from the
youngest to the oldest, the general succession in the order of
deposition of the principal minerals of the Cobalt
area proper. There appear to be, however, minor excep-
tions to this order.

III. Decomposition products, e.g., erythrite or cobalt
bloom, annabergite and asbolite.

II. Rich silver ores and calcite.
I. Smaltite, niccolite and dolomite or pink spar.

After the minerals of group I. were deposited the veins
were subjected to a slight movement. In the cracks thus
formed the minerals of group II. were deposited. A few
veins that escaped the disturbance do not contain silver in
economic quantity.

This order of deposition appears to be the same as that
of the minerals in the Annaberg deposits of Germany and in
those of Joachimsthal, Austria.* At Annaberg the uranium
ore or pitchblende is said to have been deposited earlier than
the rich silver ores and later than the cobalt-nickel minerals,
while barite, fluorite and quartz were deposited prior to the
latter. At Annaberg there are thus considered to have been
broadly five periods of deposition, while at Cobalt there
have been but three, minerals representing the first and
third periods being absent.

MINING AND MILLING.

Descriptions of the working mines, and of the methods
employed in mining and milling, in the Cobalt area, are
given in part I of the Annual Reports of the Ontario Bureau
of Mines, and in the Annual Reports of Mr. A. A. Cole to
the Temiskaming and Northern Ontario Railwav Com-
mission.

BIBLIOGRAPHY.

References to most of the literature on the Cobalt and
adjacent areas are given in the report on the " Cobalt-Nickel-
Arsenides and Silver Deposits of Temiskaming," fourth
edition, published by the Ontario Bureau of Mines, Toronto,

*Beck, "The Nature of Ore Deposits," Weed's translation, pages
285, 289.

Crusher

Stamps or Chilian Mill

Classifier

General flow sheet, Cobalt concentrators.

102

AXXOTATED GUIDE.

SUDBURY TO NORTH BAY.

Miles and
Kilometres.

439.2 m. Just cast of the station at Sudbury there is a
708 kin. hill of gabbro. Beyond this a conglomerate.

called the Ramsay lake conglomerate, outcrops
all along the north shore of the lake for two
miles. This conglomerate OYerlies a quartzite
which occurs toward the easterly end of the lake.
432.2111. (Altitude 841 feet). The quartzite is well

697 km. exposed around Romford junction, showing the
beds of the stratified rock dipping about 45
degrees S.

431. 111. The Mond Xickel Company have erected a

695. km. copper-nickel smelter about one mile south of
Coniston to treat the nickeliferous pyrrhotite
ores from Victoria mines and other properties.
Just east of Coniston a tongue of greenstone
crosses the track.
427.1 m. < Altitude 799 feet). Near YVanapitei station

689. km. there is a contact of the quartzite and Laurentian
gneiss to the east. This contact follows for
some distance the northeast-southwest course of
the YVanapitei river. Between YVanapitei and
Sturgeon Falls the railway follows a series of
valleys in the Laurentian. In these valleys are
several towns about which there are small areas
of good agricultural land. All the rock exposed
along the railway east of YVanapitei is Lauren-
tian gneiss.

383.3 m. (Altitude 687 feet 1. At Sturgeon Falls
618. km. the water power is utilized by a mill in the

manufacture of pulp from spruce wood which is
floated down the Sturgeon river. Reddish
Laurentian gneiss is well exposed about the
dam at the pulp mills.
360. m. (Altitude 654 feet). For a few miles west

580. km. of Xorth Bay the railwav skirts the north shore
of Lake X'ipissing. which is 90 miles long
and 20 miles wide. Immediately west of Xorth
Bay the Laurentian is concealed by a covering
of drift.

104

The town of North Bay (population about
8,000) is a divisional point on the Canadian
Pacific railway, and also the southern terminus
of the Temiskaming and Northern Ontario rail-
way. Both the Grand Trunk and Canadian
Northern railways have lines into the town.

ANNOTATED GUIDE.

NORTH BAY TO TEMAGAMI. COBALT AXD HAILEYBURY.

Miles and
Kilometres.

For 64 miles (103 km.) north of North Bay,
as far as the station of Doherty, the railway
crosses a monotonous succession of Laurentian
gneisses, which in many areas are characterized
by a strikingly banded structure. Generally
speaking these gneisses may be said to consist
dominantly of pink or light grey bands, and
subordinately of dark-colored or black bands, all
having the composition of granite, save some of
the darker types. Regarding the age relation of
the light-colored and dark-colored bands, it may
be said that the former are seen in some cases to
be intrusive into the dark bands, but that more
often it is difficult or impossible to determine
what the relation is. The dark bands are cer-
tainly in part elongated fragments of Keewatin
greenstones. Both dark and light bands are
injected bv pink granite and pegmatite, either
parallel with or cutting across the schistosity.
0.0 m. Leaving North Bay the elevation of which is

0.0 km. 654 ft. (199.4 rn.) the railway climbs a heavy
grade for 21.5 miles ^ 34.7 km.) reaching an
elevation of 1,290 ft. (393.3 m.) above sea level,
that being the highest point on the track in the
479 miles (772.5 km.) which separate Toronto
from Cochrane. For about a mile (1.6 km.)
from North Bay the banding of the gneisses is
very striking. The darker bands contain
biotite or hornblende. To che east of the rail-
way for a few miles the gneisses become in

places thickly studded with garnets and they may
then be referred to as garnet schists. These
schists are often intricately contorted, and are
similar to certain schists in Eastern Ontario
which are commonly classed with the Grenville
series.

io.i m. Between mileage I (1.6 km.) and mileage

16.3 km. io.i (16.3 km.) the gneisses are much covered
with superficial deposits, but pink, grey and
brown types were noted, holding few dark
bands.

What may be referred to as the Mulock
gneiss occurs in the area about Mulock station.

18.0 m. altitude 1,222 ft. (372.6 m.). It is a coarse-

29.1 km. grained, pink biotite variety in places having a

marked " augen " texture. This gneiss lacks
the striking banding of the rocks at North Bay-
Pink, light-colored gneisses with subordinate
areas of the dark banded types occur between
27. m. mileage 21.5 and Tomiko, altitude 1,167 ft.
43.6 km. (355.9 m.). On the other hand the country
between Tomiko and mileage 35 is underlain
35. m. by a banded, dark, glistening biotite gneiss, in
56.5 km. which pink gneiss is subordinate in amount.
47. m. For the next twelve miles, as far as the

75.6km. station of Bushnell, altitude 996 ft. (303.5 m.),
the rocks are poorly exposed, the last seven miles
being covered by " muskeg."
56. m. Between Bushnell and Redwater, altitude

90. km. 1,015 (309.3 m.), a dark biotite gneiss first pre-
dominates ; as Redwater is approached the dark
bands become hornblendic and chloritic, one
small lense held by the pink gneiss consisting
largely of chlorite. This latter resembles a
fragment of Keewatin greenstone schist. Both
pink and dark gneisses are injected by granite
pegmatites, cutting across or parallel with the
bands.

A variety of granitic rocks occurs between
64. m. Redwater and Doherty, altitude 1,063 ft- (324
103. km. m.). Thus, for the first three miles north of
Redwater pink gneisses predominate holding

io6

subordinate areas of grey or dark gneiss.
Between mileage 59 and 60 the rock is a
massive red granite, gneissoid in part and not
often banded. The next two and a half miles
disclose banded gneisses, many of the dark bands
of which are as basic as certain Keewatin horn-
blende schists. Between mileage 62.5 and 64 a
coarse, massive, hornblende granite is well
exposed. Dikes of fresh diabase, resembling
the olivine diabase dikes of the Sudburv nickel
area, are to be seen between mileage 56 and 64.

At Doherty, mileage 64, the first ex-
posures of pre-Cambrian sediments make
their appearance. A series of conglomerate,
greywacke, and slate-like greywacke, resting in
horizontal position, lie unconformably on the
massive, hornblende granite last mentioned.
This series of sediments, which is known as
the Cobalt series, holds numerous pebbles and
boulders of the underlying granite. Contacts
of the conglomerate and granite occur at the
railway station.
65.5 m. About one and one-half miles north of

105.3 k111- Doherty fine-grained hornblende schists of the
Keewatin series are well exposed. These are
cut by light-grey dikes of quartz or granite-
porphyry. On the east side of the track the
conglomerate of the Cobalt series rests on the
upturned edges of the hornblende schists.
66. m. One-half mile farther north, outcrops of

106. 1 km. Nipissing diabase occur. This rock is widely
distributed in Northern Ontario, and is of im-
portance because of the fact that it is closely
connected, genetically, with the phenomenally
rich silver-cobalt veins which occur near the
town of Cobalt, 36 miles (57.8 km.) to the north.
72. m. Between mileage 66 and Temagami, altitude.

115.8 km. 989 ft. (301.3 m.), good outcrops of Keewatin
schists and conglomerate of the Cobalt series are
seen. South of Temagami grey sericite schists
of the Keewatin series have resulted from the
metamorphism of quartz-porphyries.

io7

Temagami lake is one of the most beautiful
sheets of water in Northern Ontario, a fact
which caused the building of three summer
hotels on its shores. The railway station lies
at the east end of what is known as the North-
east Arm of the lake. A few hundred yards
north of the station conglomerate of the Cobalt
series may be seen resting on the jagged edges
of Keewatin greenstone schists. While to the
west of the track about two hundred yards
splendid outcrops of the Keewatin iron formation
(jaspilyte) occur. The latter, which is 1,000
ft. wide in places, is easily reached by a foot-
path, and consists of silicious magnetite inter-
banded with variously colored jaspers and cherts,
with in some instances a small proportion of
hematite.

94. m. Between Temagami and Latchford, altitude

151.2 km. 922 ft. (281 m.), the railway passes successively
over granite, conglomerate, slate-like greywacke,
quartzite, diabase, and red, banded greywacke.
The latter is well exposed on the cliffs bordering
the railway south of Latchford.

98. m. For the next four miles, as far as Gillies,

157.6. km. altitude 934 ft. (284.6 m.), the railway closely
follows the Montreal river, which empties into
lake Temiskaming 21 miles to the southeast.
At Latchford the river, which for the most part
pursues a steady southeasterly course, bends
sharply to the northeast until Gillies station is
reached when it takes its normal direction again
to the southeast. Below Gillies several miles, at
Hound and Ragged chutes, important falls on
the Montreal river have been utilized to supply
compressed air and electric energy for the silver
mines at Cobalt. At Ragged chute the air is
compressed by a simple and ingenious hydraulic
method, and is conveyed directly to Cobalt in a
24-inch pipe.

io8

Leaving Gillies station the railway passes
over Nipissing diabase, Keewatin greenstones,
and conglomerate and greywacke of the Cobalt

103. m. series, to the town of Cobalt, altitude 973 ft.

165.7 km. (296.5 m.). The town is built on the west side
of Cobalt lake, a small, narrow body of water
about a mile in length. The population of the
town, according to the census of 191 1, is 5,638.

107. m. There is a steady descent of the railway for

1 72. 1 km. about four miles to the town of Haileybury,
altitude 766 ft. (233.4 m.), on lake Temiskam-
ing. The rock-cuts and cliffs along the way
show exposures of conglomerate and grey-
wacke of the Cobalt series, and also of the
Nipissing diabase.

THE PORCUPINE AREA

A. G. Burrows.

CONTENTS.

PAGE

Introduction no

Ingress to the area no

Elevation of the area no

The first prospecting 112

Superficial deposits 113

Forest fires 113

Timber 115

Geology 115

Pleistocene 115

Pre-Cambrian 115

Keewatin 116

Basic rocks 116

Acidic rocks 118

Iron formation 120

Carbonate rocks 121

Laurentian 121

The Temiskaming series 123

The Cobalt series 124

Later Intrusives 124

The Gold Deposits 126

Origin 126

Character of gold-bearing deposits 128

Distribution of veins 132

Occurrence of the gold 132

Microscopical and other characteristics. . . . 134

Mining and Milling 138

Annotated Guide Haileybury to Swastika, Iroquois

Falls Junction and Porcupine 141

INTRODUCTION.

The Porcupine gold area, which for the past four
years has attracted much attention, is situated on the
Hudson Bay slope of northern Ontario. The latitude of
Niven's First Base Line of 1899, which runs through the
centre, forming the south boundary of Tisdale and Whitney,
is 48° 27' 54" ; consequently the area is somewhat farther
south than the Canada-United States boundary in Manitoba
and other western provinces. The camp is in the Temis-
kaming judicial district. Lying along the southern fringe
of the great clay belt of Northern Ontario, it adjoins a
prospective farming country. In this belt many townships
have been laid out in six or nine-mile squares and subdivided
into concessions and lots ; in the gold area itself and in the
adjoining country to the north, many half lots containing
160 acres each have been granted to veterans as homesteads.

During the last two years there has been little extension
of the gold-bearing area beyond what was known in 1910.
The discoveries of Hollinger and Wilson of 1909, now trie
Hollinger and Dome mines respectively, still remain the
most important that have been made, while Tisdale is by far
the most important township.

Ingress to the Area.

A branch line of the Temiskaming and Northern Ontario
railway has been constructed from Iroquois Falls (on the
main line), in a southwesterlv direction to the town of
Timmins, a distance of 33^ miles.* Timmins by railway
is 485 miles distant from Toronto.

A number of townsites have been established in the area.
The most important of these are : Porcupine, South Porcu-
pine and Lakeview, situated on Porcupine lake ; Schumacher,
on Pearl lake; Timmins, west of Miller lake: and
Mattagami, on the Mattagami river.

Elevation of the Area.

In elevation the area averages about 1,000 feetf above
mean sea level. In this respect it is similar to Cobalt, which

* 0.621 mile = 1 kilometre. f 3.28 feet = 1 metre.

112

lies 100 miles to the southeast, south of the height of land.
The divide between the Hudson Bay and the St. Lawrence
waters is not pronounced, being only about 1,300 feet
above sea level.

The highest elevation near Porcupine is along the south
boundary of Jamieson, where a felsitic ridge has an altitude
of 1,350 feet above sea level.

The country from Night Hawk lake to the Mattagami
river is one of low relief. Occasional ranges of hills reach
an elevation of 150 feet, but generally abrupt changes in
elevation are less than 50 feet. Often in a low area rocks
outcrop only a few feet above the surrounding drift and are
only a fraction of an acre in extent. Northwest, south,
southwest and southeast of Porcupine lake the country is
somewhat elevated, and rock exposures are more frequent
than in most of the area.

The First Prospecting.

Previous to the building of the Temiskaming and
Northern Ontario railway, the area was difficult of access
and little prospecting was done in it until 1909.

In 1906 some work was done by prospectors on a vein
near Miller lake and a few hundred feet from the present
Hollinger vein. Evidently seeing no gold, and having no
assays made, they abandoned the property. In the same
year claims were staked in Shaw township on what is des-
cribed in the application as a " vein of sugar quartz and
hematite iron." This is of interest since the so-called vein
is simply the upturned edges of the Keewatin iron-form-
ation.

In 1908 claims were staked by Mr. H. F. Hunter on the
east shore of Porcupine lake in Keewatin formation. Gold
was found disseminated through quartz and schist in a
sheared zone.

It was not, however, until the following year that the
spectacular discoveries of J. S. Wilson, on what is now
the Dome property, caused a rush to the district, and in a
few weeks practically all of Tisdale and a great part of the
adjoining townships and unsurveyed territory were staked
out in mining claims.

Superficial Deposits.

The area is for a considerable part drift-covered. These
drift deposits consist largely of stratified clays, sands and
gravels of post-Glacial age ; and in addition there are patches
of morainic material. Sections of stratified clay, overlain
by sand, are well exposed on the Mattagami river, north of
Pigeon rapids, and along the shores of Night Hawk lake.
Most of the islands in this lake have a rocky shore line, but
are capped by stratified material. Where the soil has been
removed the rocks are seen to have been intensely glaciated.
The fine-grained greenstones have well preserved the
scratches and grooves produced by glaciation. On several
islands were noted two sets of striations, S. 15° W. mag.,
and S. mag., the latter representing the later ice move-
ment. Owing to the lack of drainage, much of the
country, though higher than the rivers and lakes, is very
wet, but (would be suitable for agricultural purposes if
properly drained. For a description of the agricultural
possibilities of the country the reader is referred to reports
by Mr. A. Henderson.*

Forest Fires.

During the past two years forest fires have greatly
ravaged the area around Porcupine. About the middle of
May, 191 1, a fire completely destroyed the surface workings
and buildings of the Hollinger mine. From that time forest
fires were burning in the area until the middle of July. On
July 2nd, the buildings of the Dome Extension and part of
the townsite of Pottsville were destroyed.

The greatest fire of the year occurred on July nth.
when, after a prolonged dry season, a hurricane from
the southwest brought up a fire which did the greatest
damage. The surface workings and buildings of
the Dome, West Dome, Vipond, Standard, Preston East
Dome, North Dome and several other properties were
entirely destroyed. The town of South Porcupine
was completely wiped out, and almost all that part of
Pottsville which escaped the fire of July 2nd. The north
part of Porcupine (Golden City) was also destroyed. This

* Agricultural Resources of Abitibi, Bur. M'n., Vol. XIV. (1905);
Idem Vol. XV. (1906).
8—7

fire was attended by a great loss of human life, 71 in all
having lost their lives either by being burned, suffocated or
drowned.

Timber.

In the parts which have escaped the fires there is a
dense growth of timber, including white and black spruce,
jackpine, birch and poplar. It is interesting to note that a
growth of young tamarac is replacing the old tamarac trees,
which have all been destroyed in recent years by the larch
saw-fly.

GEOLOGY.

The compact rocks of the area mav all be referred to the
pre-Cambrian, and are similar to those of the Cobalt area,
described on preceding pages. However, only the Keewatin
and Temiskaming series are of importance in the part of
the area that is productive at present. The following table
shows the age relations.

Pleistocene.

Post-Glacial . — Stratified clay, sand, and peat.
Glacial. — Boulder clay.

PrE-Cambrian.

Later Intrusives. — Quartz-diabase, olivine-diabase, etc.
Igneous contact.

Cobalt Series. — Conglomerate.

U nconformity.

Temiskaming Series. — Conglomerate, quartzite, grey-
wacke, slate or delicately banded greywacke.

Unconformity.

Laurentian. — -A complex of granites older than the
Cobalt series. It intrudes the Keewatin, but its relation-
ship to the Temiskaming is not definitely known ; it may be
in part older and in part younger than the Temiskaming
series.

Igneous contact.

Keewatin. — The series consists chiefly of basic to acid
volcanics, much decomposed, and generally schistose ;
amygdaloidal basalts, serpentine, diabase, quartz or felds-
par porphyry, felsite, iron-formation and rusty weathering
carbonates, and other rocks have been recognized.

KeEwatix.

The Keewatin has a much greater distribution in the
Porcupine area than the other members of the pre-
Cambrian, and it is also of more importance economically,
since it contains the greater number of the gold-bearing
veins which have so far been discovered.

As in other parts of Ontario, the series is highly
metamorphosed, and many rocks are so much altered as to
give little evidence of their original character. However,
much of the series can be seen to consist of basic and acid
volcanics such as basalts and porphyries, with intermediate
types, although these are often altered to schists. Where
schistose, the general strike over a considerable area is
found to vary from east and west to northeast and south-
west, while the dip is generallv steep to the north:

Basic Rocks. Among the more massive rocks are
greenstones (basalts, etc.), which frequently show a
striking ellipsoidal or pillow structure. Amygdules often
accompany this structure and occur most abundantly along
the rims of the ellipses. The centres of the ellipses are
often bleached to a light greenish or whitish color, whereas
the margins are considerably darker. This structure is
frequently seen in the northwest part of Whitney township.
It is very pronounced in the greenstone along the shores of
Night Hawk lake and on the islands in this lake. On the
main land, opposite Callinairs island in Night Hawk lake,
the ellipsoidal greenstone has been rendered quite schistose,
so that the structure appears as alternate light and dark
bands. Some of the greenstones have been brecciated and
resemble conglomerate.

Serpentine occurs in parts of the area in large volume.
The range of hills immediately southeast of Porcupine lake
are largelv composed of this rock, which is impregnated
with much carbonate. Occasional veinlets of fibrous asbestos
are seen. A section of a sample of serpentine rock from

the southeast shore of Porcupine lake is made up largely of
fibrous serpentine, together with residual iron oxides
which in arrangement suggest original crystals like olivine.
The remainder of the rock is dolomite. A chemical test
showed the absence of chromium oxide in this rock.

A spotted rock, from the northeast part of the West
Dome in lot 5 in the first concession of Tisdale, is probably
an altered amygdaloidal lava. The schistose matrix con-
sists of secondary material, dolomite, sericite, etc., and the
amygdules, whose margins are stained with limonite. are
filled with calcite, sericite, and quartz. Some of the
amygdules are an inch in length.

Ellipsoidal, Keewatin, greenstone, Night Hawk lake.

An amygdaloidal rock from the 100-foot level of the
Vipond mine is entirely decomposed. The amygdules are
now stained with red iron oxide and show much clear cal-
cite. Rims of chlorite surround the amygdules, along
which are scattered grains of magnetite. There are also
some minute grains of a secondary mineral, quartz or feld-
spar.

A sample from the main shaft at the Dome Extension is
quite schistose in thin section. Rods of plaeioclase can
still be recognized, while the ferro-magnesian mineral is
entirely altered to chlorite. Quartz is present in small

grains, and calcite is abundant. Secondary feldspar is
present in the form of clear grains. The rock may have
been a diabase or basalt, but is now much altered.

Acidic Rocks. The light-colored, more massive rocks
are principally quartz-porphyries and felsite, which in
places intrude the more basic rocks. When the porphyry
occurs in some volume, as around the Hollinger mine, the
name rhyolite has been applied to it. Much of the porphyry
has been altered to a sericitic schist, and frequently a rather
massive rock can be traced into a very schistose one. This
change can be well seen in the porphyry to the southwest of
the Dome mine workings. A porphyry from the south half
of lot 4 in the first concession of Tisdale, examined in thin
section, shows the phenocrysts to be largely plagioclase
feldspar, while quartz in rounded grains is also present.
The groundmass is made up principally of plagioclase feld-
spar and quartz. Laths of tourmaline are scattered through
the rock.

The schist at the surface, and at 50 feet in No. 1 shaft
of the Hollinger mine, is fine in grain and of a light grey
color when fresh. The groundmass consists essentially of
sericite (or talc), dolomite, quartz and feldspar. In this
occur round and irregular eyes of quartz which may
represent phenocrysts in the original rhyolite or quartz-
porphyry from which the schist has probably been derived.
Cubes of iron pyrites are commonly set in the rock. Other
thin sections from the grey schists on the Timmins
properties have about the same group of minerals, and most
of them effervesce with hydrochloric acid.

The somewhat massive rhyolite exposed just southeast
of Miller lake is made up of a fine-grained matrix of quartz,
feldspar and sericite, in which are set small phenocrysts of
quartz and feldspar. The rock is much impregnated with
dolomite.

A sample of schistose rock from the 140-foot level of
the Bewick-Moreing shaft, east of Pearl lake, shows an
abundance of sericite, chlorite and calcite, with numerous
quartz grains. The rock is entirely altered, but some of the
quartz grains may be remnants of phenocrysts.

A sample of schistose quartz-porphyry from south of
the Dome mine workings shows phenocrysts of nuartz and
feldspar in a fine-grained groundmass of these minerals.

120

The extinction angle of some of the feldspar phenocrvsts is
near that of oligoclase-albite. Sericite scales are often
grouped around the crushed feldspar crystals and have pene-
trated them. Cubes of iron pyrites are abundant.

In addition to the quartz-porphyry there are numerous
dikes of a grey feldspar-porphyry. These are generally
less than 100 feet in width, and south of Porcupine lake
on the Edwards claim intrude the schistose quartz-porphyry.
One such dike of feldspar-porphyry, on H. R. 1,043 m
Deloro townhip, has been prospected for gold. The dike is
intersected with minute stringers of quartz in which most
of the gold occurs. A thin section of the rock shows the
phenocrysts to be an acid plagioclase which is fairly fresh,
but is partly invaded by scales of sericite. Plagioclase is
also prominent in the groundmass.

At times the Keewatin has been much crushed and
broken, so that the rock has the appearance of a conglom-
erate ; so much so that in the vicinity of the Dome mine,
where greywacke and conglomerate occur, it is impossible
to draw a close line of distinction between the autoclastic
rock and the true conglomerate.

Iron-Formation. Banded iron-formation, grouped with
the Keewatin, has an extensive development m parts of the
area. It outcrops frequently in the southwest part of
Whitney township, in the first and second concessions. The
disturbance in the formation here has not been so great as
in other areas. Often the bands are lying almost hori-
zontally. In places they have been somewhat brecciated,
but are otherwise little disturbed. The bands are alternate
reddish or greyish sugary quartz and magnetite or hematite.
Sometimes the narrow bands of magnetite, one-eighth inch
thick, carry a merchantable percentage of iron, but these are
relatively subordinate in comparison with the main mass of
rock. It is unlikely that merchantable iron ore will be
found in quantity. In parts of the formation iron pyrites
replaces the magnetite. Almost horizontal, interbanded
iron pyrites and silica are seen on the south half of lot 5 in
the second concession of Whitney. A sample of banded
quartz and iron pyrites gave 40 cents in gold per ton. Iron
pyrites occurs in considerable quantity with a sugary quartz
on lot 9 in the second concession, and might be worthy of
investigation as a source of sulphur.

121

Carbonate Rocks. In various parts of the area, assoc-
iated with Keewatin rocks, are carbonates to which various
terms have been applied, such as dolomite, ferro-dolomite,
ferruginous carbonate and ankerite.

There is much uncertainty as to the origin of this rusty
carbonate rock in different parts of the area. The carbonate
may occur in at least four different forms, namely, as
original bedded material, as a replacement, as vein filling,
and as a decomposition product of basic, igneous or other
rocks.

That there has been considerable migration of carbonate
solutions is shown by the manner in which almost all the
rocks of this area are more or less impregnated with it.
Sections of quartz-porphyry schist show the presence of
much calcite as a secondary mineral. Veins and veinlets
of ankerite occur frequently, not only in basic rocks, but in
the quartz-porphyry.

LaurEntian.

A few outcrops of granite occur in the township of
Whitney. This granite is a medium-grained biotite variety,
and not typical of that occurring in large volume to the
north and south of the area. In south Whitney it intrudes
light-colored porphyry of Keewatin age, but its relation to
the Temiskaming is not known.

While typical granites do not outcrop in the immediate
vicinity of Porcupine, they occur in large volume to the
north, west and south of the area, and are known to intrude
the Keewatin. Where the granites are exposed over large
areas they are medium to coarse in grain, and have been
exposed at depth by extensive erosion. It is considered
that some of the granophvre, porphyry and felsite rocks are
dike representatives of the granites, which very likely under-
lie the Keewatin and Temiskaming formations at Porcupine.
The predominant feldspar of the acid dikes is a plagioclase
(near albite), which is also prominent in many of the
granites.

123

The; Temiskaming Series.

This series of rocks has been described in preceding
pages in connection with the Cobalt area.

At Porcupine the series is of much greater economic
interest than at Cobalt, since important gold deposits have
been found in it.

The largest area of these rocks at Porcupine stretches
from the Dome mine in a northeast direction for about ten
miles. It consists of slate, quartzite and conglomerate
which have generally been greatly disturbed. The beds
have been highly tilted, dipping at angles of 70° to vertical.
A secondary cleavage has frequently been developed, and
the rocks have been rendered quite schistose. The general
direction of the strike is from N.E.-S.W. to E.-W. In this
respect the series is related to the Keewatin which has a
corresponding strike. It is evident that much of the
deformation of the Keewatin was post-Temiskaming.

The sediments at the Dome have been greatly altered to
schists. Similar rocks around Three Nations lake have been
less altered, and, except for a high dip, greatly resemble the
Cobalt series.

The succession of Temiskaming strata is well shown at
the property of the Three Nations Mining Company on lot
5 in the fifth concession of Whitney. Along the line
between the fifth and sixth concessions very much altered
Keewatin rocks, now largely serpentine and rusty carbonate,
are exposed. The contact with the Temiskaming conglomer-
ate practically follows this line. Here, at the base of the con-
glomerate, are numerous fragments of rusty-weathering
Keewatin rocks ; while farther to the south there are
numerous pebbles of acid rocks, including quartz-porphyry,
felsite, etc. The conglomerate is overlain by a narrow. band
of fine-grained black slate, which splits in very thin layers.
Overlying the slate is a greywacke which becomes coarser
towards the south. About half a mile south of the con-
cession line the rock is quite coarse-grained, and may,. be
called an arkose-like quartzite. Throughout the Temis-
kaming series there is considerable carbonate, and manv
samples effervesce briskly with acid.

It should be noted that no granite pebbles were found in
the conglomerate. It is believed that the series was laid

I24

down when the surface rocks were largely volcanics, and
that the intrusion of at least part of the granite came after
the deposition of the Temiskaming. but prior to the Cobalt
series.

At the Xorth Dome there is a strikingly banded rock
which was originally a succession of fine clay and rather
coarse sand layers. A secondary cleavage is developed at
a low angle with the upturned edges of the strata.

On the Foley-O'Brian the sediments in addition to being
highly tilted show a wavy structure along the strike.

At the Dome property, in contact with large quartz
masses, is a conglomerate which is likely basal. On the
weathered surface the included fragments of porphyry,
greenstone, schist, etc.. are conspicuous, but in freshly
broken pieces the conglomeratic character is easily over-
looked, since the rock breaks in prismatic blocks resembling
schist. The included pebbles are frequently drawn out in
the direction of the schistositv.

The Cobalt Series.

The younger series of pre-Cambrian sediments has been
observed only in small volume on the south boundary of
Langmuir township, about 15 miles to the southeast of
Porcupine lake.

Later Ixtrusives.

In all parts of the area are basic dikes which generally
are less than 100 feet in width. These dikes appear to here
represent the Xipissing diabase of Cobalt and the later in-
trusives of that area. At Porcupine thev are believed to be
much younger than the gold deposits.

126

THE GOLD DEPOSITS.
Origin.

It has been suggested, in the notes accompanying the
editions of the Porcupine map. that the quartz veins of
the area are the result of a granitic intrusion, the immense
quantity of quartz present in the veins having been supplied
by the acid magma as a differentiation product. The
primary quartz of the veins shows evidence of having- been
deposited under pressure, as it contains numerous cavities
of gas and liquid inclusions. The quartz has filled the
fissures rapidly, as there is generally an absence of well-
defined walls, except where there has been secondarv
movements. Quartz and rock are often cemented, forming
a contact like that of an intrusive.

Mr. C. YV. Knight noted the occurence of feldspar in a
quartz vein on the Miller-Middleton. one of the Timmins
locations, and suggested the relationship of the deposit to
granite or pegmatite dikes. The feldspar which is an acid
plagioclase has also been noted in other veins, including the
Xo. i vein of the Hollinger, the Rea vein, and in many of
the narrow veins in the vicinity of Three Nations lake.
The feldspar is most abundant near the margins of the veins.
The extinction angle of the feldspar in the veins on the
Three Nations Lake Mining Company's claim shows it to
be very near albite. A chemical analysis of this feldspar
gave : Soda. 10.37 Per cent. ; potash. 0.90 per cent.

The mineral scheelite, calcium tungstate. occurs in some
of the veins around Pearl lake as one of the earliest con-
stituents. It has been found in the Jupiter. Plenaurum,
Mclntyre and Hollinger. but only in very minor quantity.
It is interesting to note that scheelite generally occurs with
minerals like topaz, cassiterite, tourmaline, and arsenopyrite
in pegmatitic veins, which are considered to have a genetic
relationship with granites. The presence of scheelite in
the Porcupine veins may point to the pegmatitic origin
of the veins in this area.

Tourmaline occurs quite frequently, not only as a later
mineral in the veins but with the original quartz, a? at the
Dome Extension. West Dome and other properties.

Arsenical pyrites is abundant in the quartz veinlets on
the McAuley-Brydges claim in Bristol township.

128

The following sulphides have been recognized in veins at
Porcupine : iron pyrites, copper pyrites, pyrrhotite, arsenical
pyrites, galena and zinc blende. Of these the most abundant
is iron pyrites, which occurs in some quantity in all the
gold-bearing veins. Copper pyrites, galena and zinc blende,
although also widely distributed, occur in minor quantity.
Pyrrhotite is the chief sulphide in the veins which are being
developed in No. 4 shaft of the Dome Extension.

Only one telluride has been recognized, occurring in the
quartz-carbonate deposit at the Powell claim, M.E. 20, in
Deloro township. A chemical analysis of the mineral gave
the following results, silver 61.88 per cent, gold 0.10 per
cent., with strong reactions for tellurium, indicating the
mineral hessite. Native gold occurs as a later constituent
in minute seams in the hessite.

In support of the theory of the relation of the quartz
veins of Porcupine to granite intrusions, may be mentioned
the following:

1. The irregular occurrence of the quartz in many of the
deposits, in lenticular masses, resembling pegmatite dikes.

2. The occurrence of feldspar, scheelite, and tourmaline
in the quartz in several deposits.

3. The great pressure at which the quartz has been
deposited, indicated by the presence of liquid inclusions and
gas bubbles. These are frequently seen in quartz in
granites.

4. The frozen contacts of quartz and enclosing country
rock. The free walls seen at some properties indicate a
secondary movement in the quartz, since these walls are
slickensided. Where free walls exist they may be either
the hanging or foot wall, while the other wall is indistinct —
grading into the country rock.

5. The occurrence of narrow felsitic dikes, frequently
cut by minute veinlets of quartz, which represent the final
solidification of the felsitic magma, and which frequently
carry gold values as on Night Hawk lake.

Character of the Gold-Bearing Deposits.

The occurrence of gold at Porcupine is associated with
the quartz solutions which circulated through the fissures in
the Keewatin and Temiskaming series. The irregular
Assuring has produced a great variety of cmartz structures,

9—7

130

varying from the tabular, though often irregular or
lenticular, vein which may be traced several hundred feet,
to mere veinlets. often only a fraction of an inch in width
and a few feet in length, which ramify through a rock that
has been subjected to small irregular Assuring. This latter
variety is well illustrated in the fissuring of ankerite bands,
so characterise of some of the gold deposits of Porcupine.
Irregular and lenticular bodies of quartz often occur which
may have a width of ten or twenty feet, but which die away
in a distance of fifty feet. Again, there are dome-like masses
of quartz which are elliptical or oval in surface outline. In
some parts at least these masses can be seen in contact with
underlying rocks at a low angle, which would suggest that
they are broad lenticular masse? which have filled lateral
fissures in the country rock. The most conspicuous dome
masses are those of the Dome property, where the two
largest are about 125 feet by 100 ft. A fissure may be
vertical and regular at some points. At others it may
incline at a lower angle to the horizontal or take on a more
or less lenticular form.

The term " vein " as here used is not confined to the
filling of a single fissure with well-defined walls, for this
type of vein is rather the exception in the Porcupine area.
The Assuring has been so irregular that a " vein " in one
part may consist largely of quartz, and in another part of
numerous veinlets of quartz and intervening schist, re-
sembling a stockwerk: again, the main part of a vein may
be almost vertical in attitude, but many veinlets, branches
from the main vein, may extend laterally into the country
rock. It is often found that the values are obtained in
parts of the vertical vein which have been subjected to a
later movement and enrichment, whereas the lateral veins
have little or no value. This is illustrated in the Xo. 1
vein at the Rea mine.

The relationship of the strike of the veins to that of the
enclosing rock is often difficult to determine, since generally
along the veins there has been shearing of the country rock
which may conform to the general direction of the strike of
the veins. However, by determining numerous strikes in
the schist away from the veins, it is seen that the majority
of them are inclined to the strike of the enclosing rocks. In
dip the veins vary from vertical to nearly horizontal. In
Xo. 1 shaft of the Hollinger the vein is practically vertical.

i3i

while a series of narrow quartz veins, 6 to 18 inches wide oir
the Lindburg claim, have a dip at the surface of only 20°.
The prevailing dip of the schist in the Porcupine area is to
the north at a high angle, and frequently the veins dip dis-
tinctly to the south across the cleavage of the schist. While
it is apparent that most of the deformation of the country
antedates the vein' formation, nevertheless there is a decided
tendency in manv cases for the Assuring to be influenced
by the direction of scrrstosity, which is also a direction of

Photograph of quartz from the Swastika mine. The quartz shows dark
streaks in crushed areas. Iron pyrites is abundant along- the dark
lines, together with visible gold. Length of sample, 3% inches.

weakness ; hence we find veins having a more or less
lenticular structure, the strike of which closely corresponds
to that of the country rock.

Lenticular veins occur chiefly where the country rocks
have been intensely, sheared or rendered schistose, as around
Pearl lake. Usually when there has been less disturbance,
the veins are more likely, to have a marked difference in
strike from the enclosing rock — as around Three Nations
lake and the porphyry area south of Simpson lake. It may

132

be stated that the larger and usually lenticular veins of the
area occur where the rocks are extremely schistose, while
the narrower, better defined veins occur as stringers from
these main lenticular veins, or in less disturbed areas.

Distribution of Veins.

While gold-bearing veins occur over a wide area and
are often isolated, it is seen, from a number of those already
discovered, that they occur in groups along certain lines.
For instance, in Tisdale township there are at least three
distinct areas where the Assuring has been most pronounced.
One such area extends from the southeast end of Miller
lake, on lot n, in the second concession, in a northeasterly
direction for three miles, and includes such veins as the
McEnaney, Miller-Middleton, Hollinger, Dixon, Mclntyre,
Jupiter, Rea. and others with visible gold. The average
strike of the veins here is northeast and southwest. An
exception is a vein on the McEnaney, which strikes north-
west and southeast.

Another series, including the Smith, Davidson, Crown
Chartered and Dobie, occurs in the northeast part of the
township. To these should be added the Scottish-Ontario,
Mullholland, Hughes and Gold Reef, which are in the north-
west part of Whitney township. The general direction of
these veins is east and west.

Again, in the southeast part of the township is a group
including the Dome Lake, West Dome, Dome, and Dome
Extension, with a general strike north of east.

Similar groupings occur in other parts of the area in
which gold-bearing veins have been found.

Occurrence of the Gold.

A field examination shows that there is an irregular dis-
tribution of the gold in the quartz veins. Very often it
occurs along dark streaks in the quartz, along the contacts
of quartz and schist, or around patches of dark colored
mineral in the quartz. At the surface, rich portions of veins
are often indicated by rusty streaks or patches, while at
depth the rusty character gives place to dark grey, black or
greenish colors.

134

Microscopical and other Characteristics.

Under the microscope the gold is generally found in
areas which have been greatly crushed or in the quartz or
schist bordering on these areas.

The prominent minerals which occur in the crushed
areas are pyrite, calcite, dolomite, sericite, chlorite, tourma-
line and quartz. It is thought that most of the gold has

Streaked ore from the Jupiter mine. Porcupine. The dark lines are
tourmaline: the quartz is much crushed and contains visible gold.

been deposited along with pyrite from the solutions which
circulated in the minute fissures and crushed areas of the
primary quartz of the veins. The quartz of Xo. I vein of
the Hollinger mine shows numerous dark streaks in parts
of it and often across the width of the vein. These are
generally short and irregular in distribution. Iron pyrites
and often galena occur with the gold. Examined micro-
scopically, the quartz is seen to occur in fairlv large grains.

135

to contain liquid and gas inclusions, and to have been
subjected to secondary pressure and granulation along the
margins of the grains. The iron pyrites often occurs in well
shaped crystals which have been formed subsequently to the
crushing.

The fine dark streaks may have resulted from a shrinkage
of the quartz, forming filmy cracks which may have become
slip or crushing planes along which the richer gold-bearing
solutions were deposited at a later period.

Brecciated structure of quartz from Mclntyre main vein (natural size).

The minute dark streaks in the quartz are frequently
slickensided, and this character may often be seen in hand
specimens, as in those from the Rea or Vipond mines.

It should be noted that where cracks or fracture planes
have been produced in a quartz vein and subsequently filled
by minerals from solution, secondary quartz can be dis-
tinguished with difficulty, if at all, from the original quartz.
Hence it is not always possible to say whether visible gold
in such a vein occurs in the original or in secondary quartz.

136

Often a vein may show a width of ten feet but the
fractured portion may be only a few feet, or even inches,
wide along either wall. In this portion there may be many
streaks of dark mineral which are often parallel, giving a
banded character to the ore, as in many of the veins in the
north part of Whitney and Tisdale, namely, at the
Mullholland, Scottish Ontario, Davidson and adjoining
properties. A similar banded structure is seen at the Rea
mine. At these properties tourmaline is the principal
mineral of the streaks. The gold may occur along these
lines or in the intervening quartz, which is often much
crushed and filled with later minerals.

Several sections were examined, which showed grains
of gold apparently enclosed in the primary quartz, but the
occurrence is much less prominent than where gold occurs
in the crushed areas.

It is important to note that practically all the veins which
are gold-bearing contain considerable carbonate of varied
composition. Wherever the enclosing rocks are schistose
they always carry carbonate and frequently effervesce with
cold hydrochloric acid. Much of the carbonate of the veins
has been absorbed from the wall rock, while portions have
been formed from ascending solutions which circulated
through the veins. Pyrite and grains of gold frequently
occur in the carbonate.

Carbonate in the form of ankerite constitutes the main
portion of veins at the West Dome, Apex, and in parts of
Deloro township. This carbonate is distinctly earlier than
the quartz veinlets which intersect the ankerite veins. Both
the ankerite and quartz have been fractured and veinlets of
later carbonate deposited in them.

Since the whole surface of the area has been deeply
eroded and glaciated, there is now little evidence of
secondary enrichment. The enrichment is very super-
ficial, extending only from a few inches to a few feet
in depth. The outcrops of the veins and wall rocks are
usually discolored or decomposed, due to the oxidation of
the iron pyrites and the ferrous carbonate in the ankerite or
other iron-bearing carbonates. Cubes of iron pyrites are
occasionally obtained at the surface, while copper pyrites
and arsenopyrite also occur near the surface. Where the
veins have been oxidized to any depth, there are generally

138

some very recent water courses in evidence. Developments
so far have shown that, after this very superficial zone has
been penetrated, the character of the vein material has re-
mained the same as far as mining operations have continued.

MINING AND MILLING.

Detailed descriptions of the mining and milling oper-
ations in the Porcupine area are given in the Annual Report
of the Ontario Bureau of Mines, and in Mr, A. A. Cole's
Annual Report to the Temiskaming and Northern Ontario
Railwav Commission.

TEMAGAMI

Willkt G. Miller.

Lake Temagami, with its numerous islands and bays and
its shores covered with evergreen timber, is one of the most
beautiful sheets of water in North America. It is situated
in the Government Forest Reserve, and since the completion
of the Temiskaming and Northern Ontario Railway, the
lake has become very popular with tourists and sportsmen.
Fish and game are abundant in the vicinity of Temagami
and the numerous adjacent lakes and streams. The locality
is especially noted for moose and for bass and trout fishing.

Near Temagami station there are exposures of the
Keewatin and Cobalt series. Within a half mile north-
ward of the station an iron range of interbanded magnetite
and jasper, which has a width of several hundred feet, is
to be seen. Two or three miles northward there are deposits
of mispickel, pyrrhotite, and copper pyrites. The last-
named mineral is also found near the lake.

Good contacts of the Cobalt series with the Keewatin
are exposed along the railway a short distance north of the
station.

The schistose rocks of the Keewatin may be divided into
the paler-colored and more acid varieties, which are
deformed quartz porphyries or porphyrites, and the more
deeply colored or basic schists resulting from the shearing of
hornblende porphyrites, basalts and diabases. The extreme
deformation of the more acid types produces sericite schists,
which reveal little or no trace of their original structure.*

The iron-formation (jaspilyte) is similar to that of the
well known Vermilion range of Minnesota. It is infolded
with the Keewatin schists, all dipping at high angles.

The iron-formation, in places 1,000 feet in width, prob-
ably represents chemical sediments that were deposited on
the surface of the Keewatin volcanic rocks. At the base
of the iron-formation, there is frequently a comparativelv
thin layer of fine-grained greywacke.

Frequently the interbanded material of the iron-form-
ation contains 35 to 40 per cent, of metallic iron. By
magnetic concentration, judging from experiments that
have been performed, a merchantable ore can be produced.

*Geol. Sur. Canada, Vol. XV., 1902-3, p. 128 A et seq. Map No. 944.

139

LEG ELN D
Pre- Cambrian

Cobalt series

Conglomerate , greywacke
Unconformity
Iron format/or?

Kee wctt/rr

Mass / ve <£/"ee'is+bt7*

11 g

Ser/c/te sct/sts-

Geological map of area near Temagami railway station,
scale 1 mile to 1 inch.

(From map No. 944, Geological Survey of Canada.)

I4i

ANNOTATED GUIDE.

HAIL,E)YBURY TO SWASTIKA, IROQUOIS FALLS JUNCTION AND

PORCUPINE.

Miles and
Kilometres.

107.44 m. Altitude 766 ft. (233 m.). The town of
173 km. Haileybury has a splendid location on the east-
erly slope of a clay ridge, over-looking Lake
Temiskaming, an expansion of the Ottawa river
which here forms the boundary between the
Provinces of Ontario 'and Quebec. From the
railvvay station to the lake there is a descent of
l7S (53-2 m0- The clay, which is finely
stratified, is utilized in the manufacture of red
brick at Haileybury and New Liskeard.

One-half mile west of the station is an ex-
posure of Silurian limestone (Niagara) which
is prolific in fossils. This limestone has been
burned for lime, and is also used for road
material and building stone. It lies nearly
horizontally, and is the youngest compact rock
in the area.

112.64 m. Altitude 642 ft. (195.6 m.). Leaving
181. 2 km. Haileybury there is a descent to New Liskeard,
which is situated in a valley on Wabi bay.
Between the towns are several cuttings on the
railway which show the beautifully banded
character of the clay. Good exposures of the
Temiskaming series are to be seen along the lake
shore. Niagara limestone can also be observed
in the ridge directly west of the New Liskeard
station. New Liskeard lies almost on the south-
erly boundary of a farming country, which
stretches 35 miles along the railway to
Krugerdorf station. This area is entirely drift-
covered, while the Pleistocene deposits consist of
stratified clay, sand and gravel, considered to
have been laid down in lake Ojibway, the last of
the glacial lakes. Here and there recent water
courses have cut deep valleys in the Pleistocene
deposits, but generallv the country has a rather
flat or rolling appearance. The high ridge

143

which may be seen to the east of New Liskeard,
known as Wabi point, is composed of Niagara
limestone. Seven miles northeast of New
Liskeard station is the Casey Cobalt silver
mine, which is one of the few properties, out-
side of the main Cobalt silver area, which has
shipped high-grade silver ore.
128.59 m. Altitude 816 ft. (248.6 m.). At Earlton a
206.7 km. branch line extends from the main line to the

Elk Lake silver area.
138.48 m. Englehart, altitude 677 ft. (206.2 m.).

232.7 km. From this point a short line extends westward

to the Charlton farming area A part of this
line from mileage one to two and three-quarters
has been constructed along the north side of a
high, rocky ridge. In the rock cuttings are ex-
posed massive and schistose Keewatin rocks,
some of which are greatly altered, showing
torsion cracks, filled with calcite and quartz,
numerous faults and crushed areas. The Kee-
watin is intruded in places by diabase dikes.
Where schistose, the rocks strike N. 8o° E. and
dip N. 6o°.

146 m. Altitude 770 ft. (234.6 m.). The first out-

234.8 km. cropping of rock on the main line occurs at the

crossing of the Blanche river, just south of
Krugerdorf station. Here the track is no feet
(33.4 m.) above the raoids which are formed
by a barrier of massive, flesh-colored granite.

North of this point rock exposures become
more numerous, showing here and there through
the stratified clay. These consist of coarse,
reddish granite as far as mileage 153. Just
south of this mile the acid rock is gneissoid,
showing pink and grey bands striking N. 72° W.
Glacial striae are well preserved on the granite
showing a direction of S. io° E. This granite
has been used in the construction of the station
at Matheson.

North of mileage 153 a Keewatin area is
entered. The rocks are largely greenstones,
some of which are basalt, showing occasionally

144

ellipsoidal or pillow structure. At the south
end of the first rock cutting north of mileage
153 there is Keewatin iron formation carrying
considerable iron pyrites : at one point there is a
rusty band eight feet wide carrying streaks of
massive iron pyrites. The basic rocks are cut by
narrow, reddish, feldspathic dikes which
contain much mica. Just south of mileage 154,
one of these dikes, two feet in width, shows in
a rock cutting on the southwest side of the track.
Fifteen chains north of this mileage, a dark
mica lamprophyre cuts the greenstone.

Marked ellipsoidal structure is seen at
mileage 1 56 on the northeast side of the track.

159.74 m. Altitude 1.035 ft- (3I5-4 m- >- At Dane a
256.7 km. 17-mile (27.3 km. ) wagon road leads to the
Larder Lake gold area, where the gold occurs in
rusty-weathering carbonate and porphyry rocks
which are cut by veinlets of quartz.

At mileage i6oJ/2. reddish syenite occurs on
the south side of the track. The high range of
hills observed to the south are reddish horn-
blende syenite which intrudes the Keewatin
greenstone.

Just east of mileage 162 there is a rock cut-
ting through banded iron formation. The rock
is very rusty, and melanterite has been formed
from the disseminated iron pyrites. Keewatin
greenstone is observed continuously in the cut-
tings as far as Amikougami creek, east of
Swastika. The Lucky Cross mine is to
the south of the track, just east of the
Amikougami creek, while about half a mile
to the southwest is the Swastika mine. Between
the last mentioned creek and the Blanche river is
a ridge of grey feldspar-porphyry. Along this
porphyry ridge a number of mining claims have
been staked out. and the chief gold veins occur
where the greenstone has been intruded by this
rock.

164.7 m- Altitude 1,007 (3°6-9 m.). The town of
265. km. Swastika is underlain by conglomerate which
contains numerous pebbles of porphyry and
jasper, while the high ridge southwest of the
town is also conglomerate. Numerous narrow
dikes of red feldspar-porphyry intrude the con-
glomerate for two miles beyond Swastika.

Conglomerate and greywacke are shown in
the cuttings as far west as Kenogami station.

168.16 m. Altitude 1,013 ft. (308.8 m.). In the cutting
270.4 km. south of Kenogami station, the conglomerate
and greywacke have a vertical dip. This con-
glomerate has been provisionally classed as
" Temiskaming." The glacial striae seen on the
polished surfaces near Kenogami strike S.
55° E.

Another Keewatin greenstone area extends
north of Kenogami to mileage 178^. At the
fourth crossing of the Blanche river there is
basalt which is intruded by a dike of porphyritic
diabase.

At mileage 169 is a basalt which has been
crushed to a friction breccia.

On approaching Sesekinika lake there are
several dikes of fresh quartz-diabase. At
mileage 172 one of these has a width of 60 feet.

175.56m. Altitude 1,022 ft. (3 1 1.4 m.). Sesekinika
282.4 km. lake contains numerous islands on which
Keewatin rocks occur. On account of its
picturesqueness this lake has been reserved as
a summer resort.

HEIGHT OF UND.

The divide between the St. Lawrence and
Hudson Bay waters is crossed at mileage 177^.
At mileage 178^ the Keewatin greenstone is
intruded by dikes of hornblende syenite.
Numerous large boulders of conglomerate of
the Cobalt series are scattered along the right of

147

way south of mileage 179. This conglomerate
occurs in place at mileage 179, where the strata
of the Cobalt series are almost horizontal, show-
ing a succession in ascending order of slate,
quartzite and conglomerate.

Twenty-five chains north of mileage 180 the
Cobalt series is exposed, showing in ascending
order: slate conglomerate, two feet (0.6 m.) of
grey and red slate, 10 feet (3 m.) of coarse
boulder conglomerate. Just beyond, opposite
the north end of Twin lake, is a bluff of con-
glomerate and slate, on the west side of the
track, which is 140 feet (42.6 m.) high. A
splendid view of the pre-Cambrian peneplain
can be obtained from this bluff. North of Twin
lake Keewatin greenstones again occur, but rock
exposures become infrequent.

Ellipsoidal basalt occurs north of mileage
188, and one-half mile southwest of mileage 190
there is a ridge of Keewatin basalt 300 feet
(91.4 m.) in elevation.

205.27 m. Altitude 873 ft. (266 m.). (Matheson, the

330.2 km. centre of a farming area, is on the Black river,

a branch of the Abitibi river. McDougal's
chute is formed bv a barrier of later diabase
which intrudes basic, schistose Keewatin. The
greenstone is also cut bv a dike of grey
porphyry.)

Eleven miles east of Matheson is the Munro
township gold area. Here narrow auriferous
quartz veins occur in the Temiskaming grey-
wacke and slate.

218.03 m. Altitude Q22 ft. (281 m.). At Monteith is
350.7 km. an Ontario Government experimental farm.

222.03 m. Altitude 897 ft. (273.3 m.). Three and one-
357.2 km. half miles southwest of Kelso is the Alexo nickel
mine, a mass of nickeliferous pyrrhotite, at the
contact of rhyolite and serpentine. One theory
suggests that the ore is the result of replace-
ment in the serpentine, while another suggests a

148

differentiation from the basic rock. The rocks
are older than those of Sudbury, being of
Keewatin age.

224.87 m. Altitude 945 ft. (288 m.). The Porcupine

361.7 km. branch of the Temiskaming and Northern
Ontario railway to the Porcupine gold field
leaves the main line at Iroquois Falls Junction.
This line passes over a drift-covered area for
most of the distance to Porcupine lake. South-
west of Iroquois there is much stratified sand
and gravel, while approaching Porcupine, strati-
fied clay is observed. Keewatin outcrops at the
Porcupine river crossing", and serpentine at
mileage 21.

149

LIST OF ILLUSTRATIONS

Maps. Page

Map of Cobalt Area, showing veins and locations of sections,
scale 800 feet to 1 inch (in pocket)

Map of the Sudbury-Cobalt-Poreupine region, scale 8 nrles to
1 inch (in pocket)

Geological map showing contact of norite and Laurentian in
vicinity of Creighton mine, Sudbury (in pocket)

Geological map of vicinity of Stobie and No. 3 mines, Sud-
bury (in pocket)

Geological map of Copper Cliff offset (in pocket)

The Sudbury-Cobalt-Porcupine region 4

Sudbury nickel area 49

Part of map published in 1744 55

N.W.-S.E. and N.E.-'S.W. lines of regional disturbance 60

Geological map of area a few miles north of Cobalt 65

Route map between North Bay and Englehart 103

Geological map of area near Temagami railway station 140

Route map between Englehart and Cochrane 142

Maps for Reference.

Geological map of Sudbury Nickel Region to accompany

monograph of A. P. Coleman, scale 1 mile to 1 inch

(Mines Branch, Ottawa, 1912).
Map of Cobalt-Nickel-Arsenic-Silver Area near Lake Temis-

kaming, Ont, scale 1 mile to 1 inch (Ontario Bureau of

Mines, Toronto, 1910).
Map of Part of the Cobalt Area, scale 400 feet to 1 inch

(Ontario Bureau of Mines, 1907).
Map of the Porcupine Gold Area, scale 1 mile to 1 inch,

editions of 1910, 1911 and 1912 (Ontario Bureau of Mines).
Geological map of the area between Temagami and Rabbit

lakes (No. 944, Geological Survey of Canada, Ottawa,

1907).

Map of the Province of Ontario, scale 35 miles to 1 inch
(Department of Agriculture, Toronto, 1912).

Sections.

Colored, geological section G. H., Cobalt, to face page 80

Colored, geological section Y. Z., Cobalt, to face page 80

Generalized vertical section through the productive part of the

Cobalt area 82

Section for Reference.

Colored, General Section, R. S. D. E. T. J. U. V., through the
Cobalt area (Ontario Bureau of Mines, Toronto).

/ 150

Photographs.

Page

Rain erosion and striated surface of greywacke, Copper Cliff.. 12

Interior plain of nickel basin from acid edge, near Azilda.... 14

Quartzite showing cross-bedding, Ramsay Lake 16

Structure in gabbro, Sudbury 17

Structure in gabbro, Sudbury 18

Onaping Falls over vitrophyre tuff 19

Anticline of Chelmsford sandstone, near Chelmsford 20

Ruined anticline, Larchwood 21

Crush conglomerate in granitoid gneiss, Creighton 23

Face of ore, open pit. Creighton, early stage 24

Creighton mine, recent condition of open pit 27

Smelter, Copper Cliff • • 29

Smelter, Copper Cliff 31

Pouring slag, Copper Cliff 33

Banded iron formation, Selhvood 35

Contorted structures in iron range, Selhvood 37

Moose Mountain iron mine 39

Cobalt station, June, 1905 53

Torsion cracks in Keewatin greenstone, Cobalt 63

Temiskaming series, tilted into vertical position, between

Haileybury and New Liskeard 67

Conglomerate of Cobalt series, containing a conglomerate

boulder from the Temiskaming series 7°

The Little Silver Vein, Nipissing mine 72

Coarse boulder conglomerate, Cobalt series, Tretheway mine,

Cobalt 76

Quartz-diabase, Cobalt 84

A typical silver-cobalt vein, outcrop on Coniagas, Cobalt 91

Polished surface of silver ore . . ^. 92

An underground view in La Rose mine 94

General flow sheet. Cobalt concentrators 101

Street in South Porcupine, March, 1912 in

Stratified clay at Sandy Falls, Porcupine area 114

Ellipsoidal, Keewatin greenstone, Night Hawk lake 117

Narrow quartz veins in Keewatin carbonate schist at Dome

property, Nov., 1910 119

Narrow quartz veins (auriferous) cutting conglomerate at

Three Nations Mining Co.'s property, Sept., 191 1 122

Contact of quartz and schist, Hollinger mine 125

Quartz masses in contact with schistose conglomerate, Dome

mine, Nov., 1910 127

Part of " Golden Stairway " vein. Dome mine 129

Photomicrograph from Swastika mine 131

Streaked ore from Jupiter mine, Porcupine 134

Brecciated structure of quartz from Mclntyre main vein 135

Quartz vein on 100-foot level, McEnaney mine 137

Otto lake from Swastika mine 146

GUIDE BOOK No. 8

Transcontinental Excursion C

Toronto to Victoria and return via
Canadian Pacific and Canadian
Northern Railways

PART I

ISSUED BY THE GEOLOGICAL SURVEY

OTTAWA
Government Printing Bureau
1013

GEOLOGY LIBRARY.

CONTENTS.
PART I.

PAGE.

Toronto to Sudbury 13

Sudbury to Cartier.

by A. P. Coleman 13

Annotated guide 13

Cartier to Cold well.

by A. L. Parsons 14

Introduction 14

Annotated guide 15

The Nepheline and Alkali Syenites of the
Port Coldwell Area.

by A. E. Barlow 16

Introduction 16

Location and size of the area 16

History of investigation 17

Topography 18

Geology of the area 18

General relationships 18

Petrographic description of chief types 18

Quartz syenite 18

Red hornblende syenite 19

Augite syenite 19

White feldspathic variety 20

Nepheline syenite 21

Essexite, olivine gabbro and picrite 22

Relative ages of chief types 23

Bibliography 23

Coldwell to Port Arthur.

by A. L. Parsons 24

Annotated guide, Coldwell to Loon 24

Pre-Cambrian geology of Loon Lake district. . . 25

Introduction 25

Description of formations 27

Pleistocene 27

Keweenawan 27

Upper Huronian (Animikie) 28

35069— I \

PAGE.

Granite 28

Lower Huronian and Keewatin 29

Itinerary 29

Bibliography 30

Annotated guide (continued) 30

Pre-Cambrian geology of Port Arthur district. . 31

History of exploration 31

Geology of the district 31

Pleistocene 32

Keweenawan 32

Animikie 33

Itinerary 35

Bibliography 36

Port Arthur to Winnipeg, via Canadian
Northern Railway.

by W. L. Uglow 37

Introduction 37

Annotated guide, Port Arthur to Iron Spur. ... 39

Geology of the vicinity of Iron Spur 41

General statement 41

Keewatin 42

Seine series 42

Algoman 42

Particular description of points to be visited . 43

Orebody at the Atikokan iron mine 43

Irruptive contact of the Algoman granite

with the Seine series 45

Annotated guide, Iron Spur to Atikokan 45

Geology of the vicinity of Steeprock lake 46

General description 46

Keewatin 47

Laurentian 47

Steeprock series 47

Seine series 47

Structure of the area 48

Progress of exploration 48

Particular descriptions of points to be visited. 49
Cross section of the Keewatin and Steep-
rock series on the south shore of Falls bay. 49
Fossiliferous limestone at Point No. 1 . . . . 50
Fossiliferous limestone and unconformable
contact of the Steeprock series with the
Laurentian at Point No. 2 51

PAGE.

Fossiliferous limestone at Trueman point. 51

Brecciated limestone at Elbow point 53

Annotated guide, Atikokan to Mine Centre... . 53

Geology of the vicinity of Mine Centre 55

General description 55

Keewatin 55

Anorthosite 56

Laurentian 56

Seine series 56

Particular description of points to be visited. 56
The Keewatin series seen en route to the

mine 56

Limestone bands in the Keewatin 57

Unconformable contact of the Seine series

with Keewatin felsite 57

Irruptive contact of the Laurentian with

the Keewatin 57

Unconformable superposition of the Seine

series upon the Laurentian 58

The anorthosite and its contact with the

Keewatin 59

The Golden Star mine 59

Annotated guide, Mine Centre to Bear's Pass. 59

The Coutchiching series on Rainy lake 60

General description 60

Coutchiching 60

Keewatin 61

Hornblende gabbro 61

Algoman 61

Structure of the area 61

Particular description of points to be visited. 63

Annotated guide, Bear's Pass to Winnipeg 66

Bibliography 67

Ordovician and Silurian of Stony Mountain
and Stonewall.

by A. MacLean 69

Ordovician — Stony Mountain 69

Silurian — Stonewall 73

Bibliography 77

Winnipeg to Bankhead.

by D. B. Dowling 77

Introduction 77

The Great Plains 77

Rocky mountains 82

PAGE.

Historical geology 83

Summary description of formations 87

Ordovician 87

Silurian 88

Devonian 88

Carboniferous 88

Permian and Triassic 89

Jurassic 89

Cretaceous 89

Tertiary 92

Annotated guide 92

PART II.

Introduction to the Geology of the Cordillera.

by Reginald A. Daly.

General topography 1 1 1

Glaciation of the Cordillera 116

General stratigraphy 117

Columnar section 118

Shuswap terrane 122

Shuswap series 122

Orthogneisses and intrusive granites 126

Beltian system 132

Cambrian system 138

Ordovician system 142

Silurian system 143

Devonian system 143

Mississippian system 143

Pennsylvanian system 144

Permian system 145

Triassic system 145

Jurassic system 145

Cretaceous system 147

Eocene system 148

Oligocene system 148

Pleistocene system 149

General structure 149

Note on the igneous bodies 154

PAGE

General history 157

Specially noteworthy features 164

Bibliographic note 165

Rocky Mountains (Bankhead to Golden),
by John A. Allan.

Stratigraphy 167

Columnar section 167

Pre-Cambrian 172

Corral Creek formation 172

Hector formation 174

Cambrian 174

Lower Cambrian 174

Fairview formation 174

Lake Louise formation 175

St. Piran formation 175

Mt. Whyte formation 175

Middle Cambrian 176

Cathedral formation 176

Stephen formation 176

Eldon formation 178

Upper Cambrian 178

Bosworth formation 178

Paget formation 178

Sherbrooke formation 179

Chancellor formation 179

Ottertail formation 179

Ordovician 1 79

Goodsir formation 179

Graptolite shales 181

Silurian 181

Halysites beds 181

Devonian 181

Intermediate limestone 181

Sawback formation 182

Mississippian 182

Lower Banff limestone 182

Lower Banff shale 182

Pennsylvanian 183

Upper Banff limestone 183

Rocky Mountain quartzite 183

Permian 183

Upper Banff shale 183

Jurassic 184

PAGE

Fernie shale 184

Cretaceous 185

Lower Ribboned sandstone 185

Kootenay Coal Measures 185

Upper Ribboned sandstone 185

Post-Cretaceous? 185

Igneous complex 185

Pleistocene and Recent 186

Annotated guide, Bankhead to Golden 186

Bibliography 201

Annotated Guide, Golden to Savona . 202

by Reginald A. Daly.
Western part of the Belt of Interior Plateaus,

Savona to Lytton 234

by Charles W. Drysdale.

Essential geology 234

Introduction 234

Physiography 235

Glaciation 237

Stratigraphy 239

Summary history 242

Annotated guide 243

Coast Range, Lytton to Vancouver 256

by Charles Camsell.

Introduction 25^

Columnar sections (by Norman L. Bowen.) 257

Canyon of Fraser river 259

Physical features 259

Geology 260

Origin and history of the canyon 261

References 264

Annotated guide, Lytton to Agassiz 265

Fraser delta 271

Topography 271

Geology 272

References 272

Annotated guide, Agassiz to Vancouver 273

PART III

PAGE

Vancouver Island.

by Charles H. Clapp.

Introduction 280

General geology and physiography 280

Annotated guide, Vancouver to Victoria (Excur-
sions C 1 and C 2, section I) 286

Geology of the region around Victoria 292

Physiography 292

General geology 294

Particular descriptions 311

Excursion C 1 311

Excursion C 2, section 1 314

Excursion C 2, sections I and II 316

Annotated guide, Vancouver to Nanaimo (Excur-
sion C 2, section II) . . . 317

Geology of the region around Nanaimo 319

Physiography 319

General geology 320

Geology of the coal deposits 326

Particular description 331

Annotated guide, Nanaimo to Victoria (Excur-
sion C 2, section II) 334

References 341

Fire Clay Deposits at Clayburn, British Columbia.
by Charles Camsell.

Introduction 343

Summary of geological history of Fraser delta. . . . 344

Annotated guide 345

Geology of the region about Clayburn 347

General description 347

Particular description 348

Industrial notes 349

Bibliography 349

Victoria, British Columbia, to Calgary, Alberta. 349
Calgary to Winnipeg via Canadian Northern

Railway.

by A. Maclean.

Introduction 349

Annotated guide, Calgary to Munson 350

PAGE

The Edmonton formation on Red Deer river near

Munson, Alberta 350

Annotated guide, Munson to Dauphin via Saska-
toon ; . 355

Annotated guide, Dauphin to Ethelbert and Pine

River 357

Annotated guide, Dauphin to Winnipegosis 362

Devonian of Snake island, and south shore of

Lake Winnipegosis 363

Devonian of Dawson bay, Lake Winnipegosis. . 366

Annotated guide, Dauphin to Winnipeg 369

Bibliography 370

Winnipeg to Port Arthur.

by A.L. Parsons.

Annotated guide, Winnipeg to Kenora 370

Pre-Cambrian geology in the northern part of

Lake of the Woods 371

General geology of the region 371

Keewatin 372

Laurentian 377

Later granite 378

Keweenawan 378

Gold mines of the district 379

Itinerary 379

Bibliography 384

Annotated guide, Kenora to Port Arthur 385

PORT ARTHUR TO TORONTO

386

ILLUSTRATIONS TO PART I.
* Maps.

Page.

Itineraires des Excursions CI, C2, C3, C4, C8, C9, 13

(Itineraires des Excursions Cl, C2, C3, C4, 13

Loon lake 25

Steeprock lake. Rainy River district 49

Golden Star mine, Rainy district 59

Bears's Passage, Rainy lake (in pocket)

Stony Mountain (in pocket)

Geological map of the Plains (in pocket)

Route map between Calgary and Banff 101

Drawings and Sections.

Section through Mt. Mckay near Fort William, Ont. The
trap here bears a similar relationship to the slaty series to
that which it has in the Cobalt area. Some silver veins

in the Port Arthur area cut both the trap and the slate.

(After Dr. A. C. Lawson) 35

Projection of beaches of Lake Agassi z in vertical section. ... 96

Photographs.

Diabase sill intrusive into slate. Current River Park, Port

Arthur 32

Black Animikie siate. Prospect Street, Port Arthur 33

Slates exposed in Stewart and Hewitson's quarry, Port Arthur 34

Animikie indurated shales, Kakabeka falls 40

Open cut, Atikokan iron mine, Iron Spur, Ontario 43

Fossiliferous Steeprock limestone, Trueman point, Steeprock

lake, Ontario 52

Coutchiching mica schists dipping beneath Keewatin green-
stone, Rainy lake, Ontario 62

Inclusions of Coutchiching mica schist in Algoman granite,

Rainy lake, Ontario 65

The topography of the plains, Winnipeg to Calgary 78

The eastern edge of the third Prairie Steppe and the Glacial

drainage channels on the second Prairie Steppe 81

Plan of beaches of Lake Agassiz in Manitoba 94

TORONTO TO SUDBURY.

Between Toronto and Sudbury the route of Excursion
C i follows that of A 3, a description of which is con-
tained in Guide Book No. 6. The nickel-copper deposits
of Sudbury are described in the same guide book.

SUDBURY TO CARTIER.

A. P. Coleman.
ANNOTATED GUIDE.

Miles and
Kilometres.

o m. Sudbury — Altitude 850 ft. (260 m.). From

o km. Sudbury the main line of the Canadian Pacific
railway ascends through hills of arkose, quart-
zite, greenstone and granite to the margin
of the nickel-bearing eruptive sheet at Murray
mine (Alt. 992 ft.,) (302-3 m.), where the gossan
covering the nickel ore of the mine is widespread.
The old smelter, now in ruins, stands just
to the south of the railway. From this point
the line descends toward Azilda, passing for
two or three miles (3-2 or 4-8 km.) over gray
norite, the nickel-bearing rock, which insensibly
passes into flesh-colored micro-pegmatite ending
on a hill a little to the west of Azilda. White-
water lake may be seen to the south.
7 m. Azilda — Altitude 881 ft. (268-5 m-)- From

11 km. Azilda the route leads westward for 14 miles
(12-5 km.) through a flat plain of stratified
clay formed in old Lake Algonquin. Above
the plain rise a few dome shaped hills of gray
Upper Huronian sandstone at Chelmsford and
Larch wood. The railway crosses Vermilion
river at the latter point.
21 m. Larchwood — Altitude 868 ft. (264-5 m-)-

33-7 km. From Larchwood westward the road begins
to ascend once more over delta sands and

Tninm^trp* gravels of the ancient lake to Phelan, where
the railway follows up Onaping river through
rough hills of Upper Huronian tuff and conglom-
erate to the micropegmatite on the northwestern
side of the nickel basin. For four miles (6 • 4 km.)
the road passes between high hills belonging
to the nickel eruptive, and then enters the
Laurentian at Windy Lake, which lies to the
south.

Windy Lake — Altitude 1,221 ft. (372 m.).
Beyond this to Cartier the landscape consists
of hills of granite and gneiss, partially covered
with sand and gravel deposits of Lake Algon-
quin.

CARTIER TO COLDWELL.

A. L. Parsons.

INTRODUCTION.

The region traversed by the Canadian Pacific railway
from Cartier to the boundary between Ontario and Mani-
toba is underlain by Pre-Cambrian rocks of Laurentian,
Keewatin, Lower Huronian, Animikie (Upper Huronian)
and Keweenawan age. These solid rocks are very thinly
covered by Pleistocene glacial deposits and stratified
sands, gravels and clays. Their uneven surface contains
unnumbered lakes and numerous rivers, which constitute
the principal avenues of communication with the region
at a distance from the railway. Along the north shore of
Lake Superior the country has a different aspect, where the
Animikie and Keweenawan are present. Most of the
region is covered with a thick growth of forest.

32 m.
51-4 km.

ANNOTATED GUIDE.

Cartier — Altitude 1,364 ft. (415-7 m.).
Leaving Cartier, the first three miles (4-8 km.)
is over typical Laurentian granite and gneiss.
Near Geneva is a contact with Keewatin, and
for about 10 miles (16 km.) most of the rock is
of the typical Keewatin traps, in some instances
highly altered. This rock again gives place
to the Laurentian 12 J miles (20-1 km.) west of
Cartier, and with two exceptions the Laurentian
continues uninterrupted to Chapleau, the next
divisional point. The two Keewatin outcrops
visible in this distance are between Roberts
and Ramsay.

109m. Ramsay — Altitude 1,403 ft. (427-6 m.).
176 km.

176m. Chapleau — Altitude 1,418 ft. (432-2 m.).

283 km. The rock between Chapleau and White River
are mainly Laurentian and exhibit the
typical rounded hills formed by glaciation,
the valleys between which frequently contain
lakes and swamps. Four Keewatin areas are
crossed in this interval. The first of these is
about two miles wide (3 • 2 km.) and is first seen
9 J miles (15-3 km.) west of Chapleau. The
second and third are probably connected,
though on the railroad they are separated by
a band of Laurentian about three miles (4 • 8 km.)
wide. These exposures are about equal in
width, and the first of them extends from

236 m. 42 J miles (68-4 km.) west of Chapleau,

380 km. the milepost 58, and the third one begins one
mile (i-6 km.) west of Missinaibi and
extends for 1 1 J miles (18-5 km.). The fourth
is a small outcrop one mile (i-6 km.) west
of Williams.

307 m. White River — Altitude 1,230 ft. (374-9 m.).
494 km. At White River, a divisional point on the

railway, yards have been built for feeding and

resting cattle in transit.

Miles and
Kilometres.

38 m.
61 km.

Beyond White River for 20 miles (32-2 km.)
is a granitic region, largely covered with sand,
beyond which the Keewatin again appears
and continues with slight interruptions to
Peninsula, where the remarkable series of
laurvikite, syenites and nepheline syenites of
the Port Coldwell region begin. From this
point the scenery changes from the diversified
cliffs on the north and the broad expanse of

Lake Superior to the south.
Coldwell — Several short tunnels cut

through buttress-like projec-
tions of the rock masses. The nepheline syenite
series extends from near Peninsula to Middle-
ton.

THE NEPHELINE AND ALKALI SYENITES OF THE
PORT COLDWELL AREA.

A. E. Barlow.*
INTRODUCTION.

Location and Size of Area.

The Port Coldwell area of nepheline and alkali-syenites
is situated on the northeast side of Lake Superior, extending
from a point on the Canadian Pacific Railway nearly two
miles (3-2 km) east of Peninsula station to another point
on the same railway a short distance west of Middleton
The area underlain by these rocks, including the shore line
and offlying islands, is a little over 15 miles (24 km) from
east to west. The necessary curves, in following the sinuo-
sities of the coast line of the lake, have increased the distan-
ce along the railway to about 2 1 miles (33 • 7 km) . Its north-
ern boundary is believed never to be more than 10 miles
(16 km.) from the shore or railway. The total area under-
lain by these rocks is probably about 100 square miles (259
sq. km.)

Miles and
Kilometre:

382 m.
615 km.

* Synopsis of paper by H. L. Kerr, Toronto, Canada.

History of Investigation.

The presence of nepheline in the vicinity of Port Coldwell
was known very early in the geological investigation of
Canada, and some details respecting its mode of occurrence
are included in the Report of Progress of the Geological
Survey of Canada for 1846-47 (1), as also in the Geology of
Canada 1863 (2). Attention was directed to these early
descriptions through the discovery in 1898 by Dr. A. P.
Coleman of the University of Toronto of a dyke rich in
analcite, near Heron Bay, for which rock he proposed the
name "heronite". Subsequently it was shown that
"heronite ' was really a decomposed tinguaite (3, 4, 5, 6).

In 1900 Dr. Frank D. Adams of McGill University,
furnished under the title "On the Probable Occurrence of a
Large Area of Nepheline-bearing Rocks on the Northeast
Coast of Lake Superior" (7), a detailed petrographical
description of four thin sections prepared from two rock
specimens collected from the vicinity of Peninsula harbour
by Peter McKellar in 1870 and Dr. Selwyn in 1882. Dur-
ing the summer of 1900, Dr. Coleman again visited Heron
bay, but although successful in discovering certain dykes
rich in nepheline, he failed to locate any large area of rocks
containing this mineral.

In 1 901 another examination was made, during which
outcrops of nepheline and other closely related alkaline
syenites were revealed between Peninsula harbour and
Middleton station (8) on the Canadian Pacific railway.

In 1902 Dr. T. L. Walker of the University of Toronto
spent a few days collecting museum specimens in this neigh-
bourhood. At his suggestion Mr. H. L. Kerr of the same
institution undertook a petrographical study of the speci-
mens then collected, as well as of those obtained by Dr.
Coleman, with a view of making a more detailed examina-
tion of the whole Port Coldwell area (9).

During the fall of 1906 and again in 1907, Mr. Kerr spent
about ten weeks in all in the field gathering information
regarding the extent of country covered by the several
varieties of these syenites. Mr. Kerr's examinations and
descriptions have evidently been made with great care
and in such detail as to make possible a rather complete
and satisfactory statement of this interesting complex
of igneous rocks.
35069—2

1 8

Topography.

The Port Coldwell region is exceedingly rough and
rocky, consisting of high rounded hills scantily covered
with soil or drift material, and therefore easy of geological
examination. The central part is in general of higher
altitude than the remainder, gradually sloping both to the
east and west. The highest point is a hill on Pic island
which, according to aneroid determination is 850 feet
(259 m.) above the lake. In the vicinity of Red Sucker
and in the Coldwell peninsula some of the elevations vary
from 250 to 700 feet (76 to 213 m) above the lake,* Fires
have destroyed most of the forest in the vicinity of the
railway.

GEOLOGY OF THE AREA.
General Relationships.

It is impossible as well as unnecessary to describe in
detail the mineralogical composition of all the varieties of
these syenites, for as usual their extreme and rapid variation
in this respect is one of the most noteworthy features of
their development. They are all, however, differentiation
products of a highly alkaline magma representing one
phase of plutonic intrusion. Although for purposes of
description they may be considered as divisible into seven
groups, it must be understood that no natural line exists
between these respective subdivisions.

1. Quartz syenite.

2. Red hornblende syenite.

3. Augite syenite (laurvikite).

4. White syenite.

5. Nepheline syenite.

6. Essexite, olivine gabbro and picrite.

7. Camptonite.

Petrographic Descriptions of Chief Types.

Quartz syenite. — Quartz syenite is perhaps the least
important of these groups, for it is a comparatively rare

* The mean water level of Lake Superior (1871-1900) was 601 .7 feet (183.38 m.)
above mean tide level.

(quartziferous) variety of both the red hornblende syenite
and the augite syenite or laurvikite. It is medium grained,
of a dark red colour, in places assuming a distinct greenish
tinge. It is typically developed in the vicinity of Red
Sucker. The feldspar is a cryptoperthitic growth of
orthoclase and albite. Green hornblende, often much
fractured and decomposed, is the prevailing coloured
constituent. Occasionally there is a very little biotite.
Quartz occurs in very small amount, both free and gra-
phically intergrown with the feldspar. Magnetite, resulting
from the decomposition of the hornblende, is usually
abundant. Apatite, fluorite, pyrite, and secondary calcite,
the accessory minerals, are sparingly represented.

Red hornblende-syenite. — The red hornblende syenite
is perhaps the most important of the subdivisions mentioned
for, from the field work so far accomplished, it seems to
cover the largest area. The deep red colour of the very
abundant feldspar, in contrast with the dark green of
the greatly subordinate hornblende, gives the rock a
pleasing and conspicuous appearance. It is usually inti-
mately associated with the darker coloured augite syenite,
into which it differentiates by insensible gradations. This
scarcely perceptible transition is well illustrated by expos-
ures north of Peninsula harbour and along the railway
between Coldwell and Middleton. Pegmatitic phases,
in comparatively narrow dyke-like forms, intersect the
associated rocks and are present in the midst of the parent
plutonic mass. The rock is composed mainly of feldspar
(orthoclase and microperthite) and hornbelnde. This
hornblende, which is a variety closely related to barke-
vikite with strong pleochroism in colours ranging from
light yellowish green to chestnut brown, is always in
subordinate amount, especially in coarse-textured varieties.
Pyroxene (diopside) rarely occurs except as a kernel in the
centre of the hornblende individuals. Biotite is usually
present in very small quantities. Sphene of characteristic
shape, apatite in comparatively large crystals, and mag-
netite, as accessory minerals, complete the list of constitu-
ents.

Augite syenite. — The dark coloured augite syenite,
which occupies so large an area in the vicinity of Peninsula,
is one of the most interesting of the rock-types represented
in this district. It varies in colour from dark brownish-
grey to almost black. Transitional phases are dull
35069—2!

reddish-grey or soapy brown. Freshly broken surfaces
exhibit the brightly gleaming surfaces of plate-like or
lath-shaped feldspar. These idiomorphic feldspars are
frequently Carlsbad twins, often with a handsome bluish
shimmer. The feldspars are greatly predominant, but,
owing to their prevailing dark colour, which is due to
inclusions, the relative paucity of bisilicate material is
not noticeable except upon close inspection. The rock
is coarse in texture, the feldspars averaging a quarter of
an inch ((-6 cm.) in length and breadth, but only a tenth of
an inch (-25 cm.) in thickness.

The mineral constituents are principally feldspar and
pyroxene with subordinate amounts of hornblende, biotite
and olivine; magnetite, apatite and pyrite are accessory
constituents. The feldspar is for the most part a micro-
perthitic intergrowth of albite and orthoclase, although na-
tron-orthoclase, orthoclase and plagioclase are also present,
but are relatively unimportant. Pyroxene is the character-
istic dark mineral. In the Peninsula area this mineral
shows a pale brown interior with a deep green border, and
is undoubtedly one of the aegirine-augite series. In out-
crops, near Coldwell as well as between the crossing of
Little Pic river and Middleton station, the augite is pale
violet, sometimes bordered by brown barkevikite. In
the western part of the Peninsula area the pyroxene is
commonly diopside, frequently surrounded by a border
of brown barkevikite and bright blue arfvedsonite. Olivine
is usually present but is not an abundant constituent
except in the vicinity of Middleton. The rock in the
cutting east of Penisnula near Craig's gravel pit contains
an olivine which, between crossed nicols, resembles sphene.
It was identified by Brogger, who states that it corresponds
very closely with the olivine present in the laurivikite of
southern Norway. Hornblende, usually barkevikite, occurs
sparingly. Arfvedsonite is also noticeable, and very
occasionally riebeckite, distinguished by its pleochroism
in deep bluish colours. Biotite is an unimportant consti-
tuent. Magnetite, pyrite, apatite, and bluish fluorite
are the accessory constituents present.

White feldspathic variety. — The white feldspathic
variety, which is closely related to the nepheline syenite
occurs about the centre of Big Pic island. The white
feldspar, which is by far the most abundant mineral, is
chiefly orthoclase or albite or graphic intergrowths of these.

The chief of the dark coloured constituents, which are
usually grouped together, is a very deep brown hornblende.
A few scales of muscovite and rare fragments of pyroxene
enclosed in hornblende were noticed. Magnetite and
apatite are conspicuous associates of the hornblende and
biotite. Nepheline, usually decomposed to hydronephelite.
is sometimes present in very small amount.

Nepheline syenite. — The nepheline syenite may in
a general be described as a medium grained rock of granitic
habit varying from pale grey to dark grey in colour.
Many outcrops are pinkish or purplish owing to the relative
abundance of hydronephelite, a decomposition product
of the nepheline. When present in very considerable
amount, as is often the case, it produces a striking and
beautiful rock. Gneissoid structure is very uncommon,
but occasionally a peculiarly banded structure, due to
the segregation chiefly of the darker coloured minerals,
is in evidence. Weathered surfaces are characteristically
pitted owing to the rapidity with which nepheline de-
composes.

The most abundant mineral constituent is feldspar.
Nepheline sometimes constitutes one-sixth of the whole
rock mass (hill east of Coldwell station). Hydronephelite
is always present, while hornblende and magnetite and the
less abundant pyroxene are also readily distinguishable.
In most instances the coloured constituents are very
subordinate, but in some cases they form the bulk of the
rock.

All the feldspars belong to the natron-orthoclase-
microperthite series. All gradations from undoubted
pure natron-orthoclase to distinct microperthitic inter-
growths of orthoclase and albite are found. Nepheline
is always the last mineral constituent to crystallize, occupy
ing the irregular interspaces between the other constituents.
As a rule it is usually decomposed in part, or altogether,
to hydronephelite. This orange-red hydronephelite is
the most striking mineral constituent of the nepheline
syenite. It is undoubtedly the orange-coloured nepheline
of the original descriptions by Logan. This mineral is
very abundant and characteristic. It occurs both in
simple individuals, often of microscopic dimensions and
sometimes with centres of unaltered nepheline still
remaining, and also in aggregates of several individuals
up to half an inch (1-27 cm.) or even more in diameter.

Sodalite is almost entirely absent from the nepheline
syenites of this area. It does occur, however, in the
highest hill southwest of Cold well, on Pic island and about
two miles (3-2 km.) north of mile post 78.

Hornblende is much the most abundant ferromagnesian
constituent. There is a green and a brown variety.
The optical properties of the brown hornblende suggest
barkevikite, although no confirmatory chemical analysis
was undertaken. The colouring of the individuals is
by no means uniform, but pale interiors with deeply
coloured borders are the rule; often the crystals have a
spotted appearance. Pleochroism is very marked, vary-
ing from greenish yellow to chestnut brown in the brown
variety, and in the green hornblende from straw yellow
to deep green. Poikilitic structure mainly with feldspar
is common. Pyroxene, ranging in composition from
deep green aegirine-augite to pale coloured diopside, and
often surrounded by a border of hornblende is usually
present even in specimens that are rich in hornblende.
The pleochroism of the aegirine-augite is very strong and
from yellow to grass green. Aegirine-augite is especially
characteristic of varieties rich in nepheline. Frequently
it forms a rim around the paler coloured diopside. Biotite
is by no means a common constituent, although in one
locality (west part of Coldwell peninsula) it is the chief
ferromagnesian mineral. Magnetite as an inclusion is
always present, and comparatively large apatite crystals
are common. Occasionally muscovite, sphene, pyrite and
purple fluorite are noticeable.

Essexite, Olivine Gabbro and Picrite. — The basic
rock of the Coldwell massif are undoubtedly the oldest of
the series. They are very variable in composition. The
more common type seen in the neighborhood of Coldwell
is a dark grey rock of medium texture with gleaming
crystals of biotite. The dark coloured constituents
represent more than three-fourths of the whole rock mass.
Thin sections show augite, olivine, biotite, hornblende,
labradorite, some orthoclase, occasionally nepheline and
much magnetite with apatite as the chief accessory con-
stituent.

Most of the dykes of the region are small, ranging from
a couple of inches (5cm.) to four feet (i-2m) in width.
They are usually of a slate grey colour and very fine grained.
Many of them are intermediate in composition between

camptonite and essexite. The camptonites are the prin-
cipal dykes of the area. They are composed chiefly of
hornblende, biotite, feldspar, magnetite, some pyrite,
very little apatite and secondary calcite.

RELATIVE AGES OF CHIEF TYPES.

According to Brgoger, the rocks of the Norwegian sye-
nite area were derived from a common magma basin,
through a succession of irruptions beginning with the basic
rocks and forming a continuous series to the most acid
granites. He also states his belief that the later basic
dykes found cutting the main rock mass represent the final
depletion of the original magma basin. According to
Kerr, the oldest rocks of the Port Coldwell complex are the
basic picrites, olivine gabbros and essexites; while as in
Norway, the youngest rocks of the region are the narrow
basic dykes, camptonites, etc. Next in order of age to the
oldest basic intrusives are the augite syenite or laurivikite,
the red hornblende syenite, and the nepheline syenite.

The difficulties of assigning a definite succession, for the
whole area can be understood only by those who have
made the attempt in other districts. To the writer of this
account, which is an epitomized statement of Kerr's con-
clusions, it seems that the general succession proceeding
from the oldest to the youngest was as follows: — ■

1. Picrite, olivine gabbro and essexite.

2. Augite syenite or laurivikite.

3. Nepheline syenite.

4. Red hornblende syenite

5. Quartz syenite.

6. Camptonites, etc.

These syenites are all intrusive into the greenstones and
greenstone schists of the Keewatin and, so far as can be
judged, merge without any sharp line of delineation into
granites usually classified as Laurentian.

BIBLIOGRAPHY.

1. Logan, Sir Wm. E. Report of Progress, Geol. Survey of

Canada, 1846-47. pp. 29-30.

2 Geology of Canada, 1863, pp. 80-81,

480, 647.

3. Coleman, A. P. . . ."Port Coldwell Region": Ann.

Rep. Bur. of Mines, Ont., 1898,
pp. 146-149.

4. "Dyke Rocks near Heron Bay":

Ann. Rep. Bur. of Mines, Ont.,

1899, pp. 172-174-

5. "A New Analcite Rock from Lake

Superior": Jour, of Geol., Vol.
VII, 1899, pp. 431-436.

6 " Heronite or Analcite Tinguaite ' ' :

Ann. Rep. Bur. of Mines, Ont.,

1900, pp. 186-191.

7. Adams, Frank D. ."On the Probable Occurrence of a

Large Area of Nepheline-bearing
Rocks on the Northeast Coast
of Lake Superior": Jour, of
Geol., Vol. VIII, 1900, pp. 322-
325..

8. Coleman, A. P. . . ."Syenites near Port Coldwell":

Ann. Rep. Bur. of Mines, Ont.,
1902, pp. 208-213.

9. Kerr, H. L "Nepheline Syenites of Port Cold-

well": Ann. Rep. Bur. of Mines
Ont., 1910, pp. 194-232 with map.

COLDWELL TO PORT ARTHUR.

A. L. Parsons.
ANNOTATED GUIDE. (Coldwell to Loon).

Miles and Kilometres
from Sudbury.

391 m. Middleton — Altitude 691 ft. (210-6 m.).
629 km. From Middleton the railway passes through a

region underlain by Keewatin rocks, which .

extends to Jackfish, a fishing village on Lake

Superior.

407 m. Jackfish — Altitude 632 ft. (192-6 m.). Near

658 km. Jackfish station the contact of the Keewatin

K"!oSaltres anc^ Laurentian is seen. The interval between
i ome ies. station and Schreiber is occupied entirely

by Laurentian rock.

426 m. Schreiber — Altitude 993 ft. (302-6 m.).

688 -5 km. Keewatin trap extends with some interruptions
for about five miles (8-0 km.) west of Schreiber,
after which the Laurentian and Pleistocene
gravel deposits extend almost uninterruptedly
to Hartley, where the Animikie is first seen.

From Hartley most of the rock exposures as
far as Port Arthur are of Animikie and Kewee-
nawan, with underlying Laurentian bosses.
Occasionally Keewatin rocks are present, but
these are a minor feature. Many gravel
deposits, exhibiting cross-bedding, occur. The
best views of the Animikie and Keweenawan
rocks are obtained near Kama, Nipigon and Red
Rock.

489 m. Nipigon — Altitude 681 ft. (207-5 m)-
787 km.

531 m. Loon — Altitude 1,000 ft. (304-8 m.).

854-5 km.

THE PRE-CAMBRIAN GEOLOGY OF LOON LAKE
DISTRICT.

Introduction.

The region around Thunder bay was first described
geologically in a brief report by Sir W. E. Logan, (1),
who also gave a more extended description of the rocks
at a later date (2) and mapped the formations as they were
then known (3). Dr. R. Bell (4) explored much of this
region in 1869 and described many of the rocks. He also
prepared a map on which, however, geological boundaries
are lacking. The first report accompanied by a detailed
map was prepared by E. D. Ingall (5), who not only
described quite minutely the silver-bearing rocks of
the region, but gave a description of the silver mines.
Later the investigation of the iron ores of this region
was taken up by W. N. Smith (6, 7) upon whose work
the following classification of the rocks is based.

Pleistocene Glacial drift.

Unconformity.

Keweenawan (Nipigon) Conglomerate, sandstone,

marl; diabase sills.

Unconformity.

Upper Huronian (Animikie) . Iron-bearing formation and

black slates.

Unconformity.

Lower Huronian Greywacke, greenstone,

granite.

Unconformity.

Keewatin Green schists, greenstones,

mashed porphyries.

Mr. Smith's article in the Bureau of Mines report was
unaccompanied by a map, though one was published in
the Mining World and was used with minor changes by
L. P. Silver the next year in his report on the Animikie
iron rangs (8). In accordance with the findings of the
Special Committee on the Lake Superior region (9) Mr.
Silver altered the legend given by Mr. Smith, so that his
interpretation of the geological sequence is as follows: —

Pleistocene Glacial drift, residual clays,

beach sands and gravel.

Unconformity.

Logan Sills Diabase, diorite or gabbro

intruding all the following
formations.

Igneous contact.

Keweenawan (Nipigon) Conglomerate, sandstone,

impure marls.

Unconformity.

Upper Huronian (Animikie). . Iron - bearing formation,

black slates, impure lime-
stone and quartz conglom-
erate.

Unconformity.

Middle Huronian Granite (igneous contact).

Lower Huronian Conglomerate, greywacke,

greenstone, quartz por-
phyry, amphibolite.

Unconformity.

Keewatin Quartz porphyry.

The map accompanying Mr. Silver's report has been
used in the preparation of the accompanying sketch map

though the correctness of certain portions of it may be
questioned. To the writer it would seem that a consider-
able portion of the rock mapped as Lower Huronian should
be included in the Keewatin, particularly that situated
about one half mile south of Loon station, near Wylie's
camp. The age of the granite also may be called in question
by some but, if the definition of the Special Committee
on the Lake Superior region be accepted, it would not be
classed as Laurentian without some explanatory note.

Description of Formations.

Pleistocene. — Of this formation little can be said,
as no detailed work has been done toward differentiating
the various types of deposits, which include extensive
areas of glacial drift and assorted sands, clays and gravel.

Keweenawan. — This series consists of extensive deposits
of conglomerates, sandstones and marls. Some writers
also include the Logan sills. In the area visited by the
excursion no extensive deposits of sandstone are seen but
the other features are well shown. In a cut on the Canadian
Pacific railway one mile west of Loon an exceptionally
fine outcrop of conglomerate, interbedded with small bands
of sandstone is exposed. The boulders of the conglomerate
are principally granite, though greywacke, iron formation
and slate (Animikie), and amphibolite also occur. This
conglomerate is cut by two narrow dykes of trap presum-
ably connected with the Logan sills. The marls and impure
sandstones are extensively developed near Silver lake,
and in these are numerous veins sometimes containing
sphalerite, galena and barite, but more frequently con-
taining amethyst.

Possibly the most striking feature of this series is the
trap formation known as the Logan sills. These intrude
not only the older rocks but the Keweenawan as well,
and are referred by some writers to a later age, while
others look upon them as an integral part of the Keween-
awan. These sills seldom exhibit their intrusive nature but
appear as great lava sheets lying in a horizontal position
over the Keweenawan and Animikie. The intrusive con-
tact is best seen at Port Arthur, but near Loon the Animikie
slates and iron formation are occasionally found overlying
the diabase sills.

Upper Huronian (Animikie). — This series has been
divided by Silver into the following divisions.

1. Black slate.

2. Upper iron formation.

3. Slate (somewhat calcareous.)

4. Thin bedded impure limestones.

5. Iron formation proper.

6. Quartz conglomerate.

The last of these is not more than six inches (15 cm.) in
thickness, where it has been seen in this vicinity and con-
sists of pebbles of vein quartz.

The other five members of the series are reduced by
Mr. Smith to four divisions by omitting the thin bedded
limestones which, according to an analysis by Mr. A. G.
Burrows (8, p. 163), would appear to be ankerite in which
the iron has been oxidized to ferric oxide. Mr. Smith
looks upon these four divisions as representing one "con-
tinuous period of deposition during which the conditions
varied between those of chemical and probably also
organic sedimentation, producing the iron-bearing forma-
tions, and those of mechanical sedimentation with the
production of the slates." (6).

The upper black slate has not been found around Loon
lake, though in other places it is well developed. The
upper iron formation is a thin bedded cherty iron carbonate
resembling in texture the jaspilite of the Vermilion and
Mesabi ranges in Minnesota. 'It varies in colour from
dark grey to very light-coloured, although the most
characteristic phase is a dark and light-
banded rock. '(6)

The lower iron formation consists essentially of taconite,
and all stages in the formation of iron ore may be observed
in this formation. The slate between the upper and
lower iron formations has not been described nor has any
outcrop been located either on a published map or in
printed descriptions.

Granite. — North of Loon lake is a series of hills of
granite intrusive into the rocks which have been assigned
to the Lower Huronian and the Keewatin. These hills
are dome shaped and have been denuded by glaciation.
That the original form of the intrusive mass was not mater-
ially different from the present form is shown by the
presence of contact breccia over the surface of the hills.
These masses are similar to if not identical in composition

with the granites that throughout this region have been
referred to the Laurentian.

Lower Huronian and Keewatin. — Considerable differ-
ence of opinion is shown by those who have made a careful
study of the formations in this region as to the dividing
line between these two series. The writer has visited
only one of the outcrops, which lies about a half mile south
from Loon station and in his opinion it would be referred
to the Keewatin if seen in a region where the bulk of the
rock belonged to that age. The difficulty of making a
distinction between the rocks of the two formations in
this region is increased by the highly altered condition
of the rocks, few of which show much trace of their
original character. The two series consist of quartz
porphyry exhibiting flow structure; greywacke, which
has been altered to a considerable extent to schist; green-
stone and a conglomerate, which, from the one illustration
given (8) and the description of the constituents, may be
compared with the Keewatin agglomerates of the friction
breccia type.

ITINERARY.

In a southeasterly direction from the station at Loon
is an outcrop of highly altered Keewatin or Lower Huronian
which is exposed near a fork in the road. At Wylie's
camp the same rock is well exposed. This rock shows
considerable contortion and some minor faulting and is
very similar to the more highly altered phases of the
Keewatin. Along a trail to Silver lake from this exposure
Animikie iron formation is well exposed at several places.
The alteration of taconite to iron ore is well exemplified
in an exposure on the south side of the trail and in the
old shaft near Flaherty's camp. Good hematite (kidney
iron) and taconite are well exposed at the tunnel on Fla-
herty's claim. Near this tunnel a fault is said to separate
the Animikie from the Keweenawan. Some time will be
devoted to the contact of Animikie and Keweenawan and
to the character of the more marl-like material of the
Keweenawan.

Returning southward along the trail the contact of the
Animikie slates with the Logan sills may be noted. Con-
tinuing along the trail the Animikie may occasionally be
found lying on the top of this sill. A view of Lake Decep-

tion well illustrates the type of lake scenery to be found
in the Keweenanwan and Animikie rocks. Occasionally
taconite, along with the Animikie slate, is found overlying
the sill. A magnificent view of Thunder bay and Thunder
cape can be seen from one of the more open spots a little
farther along. In descending from this last point to the
valley the contact of the sill with the underlying Animikie
slates is passed. To the north is another exposure of
taconite upon which some prospecting has been done.
One mile west of the railway station, in a railway cut. is
a remarkable conglomerate intersected by two small
dykes apparently connected with the Logan sills.

BIBLIOGRAPHV.

1. Logan, \V. E Rep. of Progress, G.S.C. 1846-7,

pp. 1-46.

2. Geologv of Canada, Rep. of Progress.

G.S.C. 1863, pp. 67-86.

3. Rep. of Progress, G.S.C. 1863,

Atlas.

4. Bell. R Rep. of Progress, G.S.C, 1866-69.

PP- 3I3-364-

5. Ingall. E. D Ann. Rep. G.S.C. (New Series) Vol.

Ill, Pt. F.

6. Smith. W, X Ont. Bur. Mines, Vol. XIV, 1905,

Pt. I, pp. 254-260.

7 Mining World, Vol. XXII, 1905.

pp. 206-208.

8. Silver, L.P Ont. Bur. Mines, Vol. XVI, 1905.

Pt. I. p. 156-172.

9. International Committee on Pre-Cambrian Xomencla-

ture. Jour. Geol. Feb. -Mar. 1905,

AXXOTATED GUIDE— (Continued ).

Miles and

Kilometres One mile fl -6 km.) west of Loon a remarkable

from ^udburv. , /■ , •%

* conglomerate is exposed in a railway cut.
From this point to Port Arthur the rock is
of diversified character, including Laurentian.
Keewatin, Animikie and Keweenawan, with
no very striking exposures of any of them.
554 m. Port Arthur. — Altitude 608 ft. (189-3 m-)-
891 -5 km.

THE PRE-CAM BRIAN GEOLOGY OF PORT
ARTHUR DISTRICT.

History of Exploration.

Port Arthur district has been widely known for many
years because of its silver mines, which were at one time
large producers. Of these, Silver Islet mine was the most
noted, not only for the amount of silver obtained from it,
but also for the Frue vanner which was invented by men
connected with the mine and first used in the concentration
of Silver Islet ore.

The first important description of this district was
prepared by Sir. W. E. Logan (1). This was followed by
a more extended description and a geological map by the
same author at a later date. (2).

The explorations of Dr. R. Bell along the north shore of
Lake Superior in 1869 (3) added materially to our knowledge
of the rocks of this region, but unfortunately the map
accompanying the report shows rib geology so that it is
difficult to estimate the scope of his work.

The first important work dealing in detail with the
silver deposits was done by E. D. Ingall (4), who shows in
a sketch map the geological boundaries as then known
and the location of the mines. He also prepared a geological
and topographical map of Silver Mountain mining district
which gives the essential features of the geology of this
region. A resume of this report is given by Dr. W. G.
Miller (5) to show the similarity of the silver deposits of
Cobalt with those of Port Arthur district.

The latest work in this region was done by Dr. N. L.
Bowen (6), whose report supplements that of Mr. Ingall
by including the later mine development.

Geology of the District.

The geology of Port Arthur district is simpler than it is
near Loon lake, because of the absence of the Keewatin
and Lower Huronian . Only the Pleistocene, Keweenawan
and Upper Huronian or Animikie occur in the immediate vi-
cinity of Port Arthur. Laurentian and Lower Huronian
rocks are to be found within four miles (6-4 km.) to the
north of the city but are not exposed within the area visited
by the excursion.

Pleistocene. — The Pleistocene has not been carefully
studied, but consists not only of till, but also of assorted
sands and gravels which frequently she"- marked cross-
bedding. This latter feature is to be stcii -a^ many of the
gravel pits along the railways where excavation has been
recently done.

Diabase sill intrusive into slate; Current River Park, Port Arthur.

Keweenawan. — The Keweenawan in this region con-
sists largely, if not entirely, of great masses of diabase
which were intruded into the Animikie slates and iron for-
mation in the form of extensive sills, known as the Logan
sills. These sills have a marked effect upon the topography
of the region, giving rise to flat topped hills,
the upper parts of which are very precipitous, though
the lower parts have gentle slopes due in part to the forma-
tion of talus. It was formerly supposed that these sills
were surface flows as they were found capping the hills,
but Dr. A. C. Lawson (7) showed that they were intrusions.

This rock is well shown in Current River park where a
large area of rock was stripped of its covering of recent
deposits by a fl - 4 caused by the bursting of a dam. Most
of the surface :uck so exposed is compact diabase, but
numerous patches of black Animikie slate, ranging in
thickness from a few inches to several feet, are scattered
about over the surface. This slate is considerably baked
by contact netamorphism, and the sill itself is finer grained
near the contact than elsewhere, though at no part does it
become very coarse grained. In some places through segre-

Black Animikie slate; Prospect Street, Port Arthur.

I gation of the phenocrysts of labradorite the rock grades
from a typical diabase into masses from two to ten feet
(.6 to 3 m.) in diameter having the composition of anortho-

j site.

Animikie. — The Animikie or Upper Huronian is
essentially a sedimentary series and is important as a
silver and iron-bearing formation. The complete section
is not well exposed at Port Arthur, but two of the members
35069—3

are well developed. The complete series is best observed
near Kakabeka falls on Kaministiquia river. (6) It con-
sists of (i) iron formation, including taconite, jasper,
chert etc., (2) black slate, (3) grey quartzite with grey
slate and (4) grey argillite. This agrees substantially
with the sequence given by W. N. Smith (8) though the
nomenclature is slightly different. It however, omits the
basal conglomerate of L. P. Silver (9) as well as his thin
bedded, impure limestone, which apparently are to be
grouped with the iron formation.

Slates exposed in Stewart and Hewitson's quarry, Port Arthur.

This series is important economically, containing silver
veins and extensive deposits of iron ore. Heretofore the
iron deposits have not been so important in the Animikie
of Ontario as in the same formation in Minnesota and but
little mining has been done. Prospecting has however
revealed several deposits of good ore of greater or less
extent. In Port Arthur district, interest in this series has
centered chiefly upon the black slates in which nearly all

the silver discoveries have been made. The silver is found
in fissures in this rock near the intrusions of Keweenawan
diabase, and in some cases the veins have crossed the dia-
base as well as the slate. The dark colour of the slate is
largely due to the presence of carbonaceous matter which
is thought to have been an important factor in the pre-
cipitation of the silver, for the silver is said to be always
accompanied by carbonaceous matter.

979.HL above Lake Superior

Lake level

Section through Mt. McKay near Fort William, Ont. The trap here bears a similar
relationship to the slaty series to that which it has in the Cobalt area. Some
silver veins in the Port Arthur area cut both the trap and the slate. (After Dr.
A. C. Lawson.)

The most noted mines of this vicinity are the Silver
Islet, Silver Mountain, Beaver, Badger, and Porcupine.
None of these have been worked to any great extent since
the fall in the price of silver in 1892.

Itinerary.

At Current River park the Keweenawan traps and over-
lying slate are first noted. Usually the slate is not more
35069— 3§

than a foot in thickness, but near the Canadian Pacific
Railway track there is an exposure several feet in thick-
ness.

Returning to the city an excellent view of Mt. McKay
may be seen from the Lookout near the collegiate building.
By reference to the accompanying section the effect of
the diabase sills upon the form of the mountain may be
observed. The Lookout itself is interesting in that it
is built of materials representing most of the Pre-Cambrian
rocks of the region. An outcrop of black Animikie slates
occurs near the corner of Prospect Street and the car
line, and at the corner of Hebert and College Streets is a
good exposure of taconite. Slates and Keweenawan trap
are well exposed in the Stewart and Hewitson's quarries
at the end of Hill street, and in the former, slaty cleavage
is well developed. Silver was found in a vein in this quarry.
The large quarry near the crushing plant shows several
well defined veins, filled with calcite, fluorite and barite,
which penetrate both slates and diabase.

Bibliography.

1. Logan, W. E

Rep. of Progress, G.S.C., 1846-47,
pp.1-46.

Geology of Canada, Rep of Pro-
gress, G.S.C., 1863, with Atlas
Rep. of Progress, G.S.C., 1866-99,
PP. 3I3-364-

Ann. Rep. G.S.C., Vol. Ill, Pt. F,
1887-88.

Ont. Bur. Mines, Vol. XVI, Pt. II,
PP- 150-156.

Ont. Bur. Mines, Vol. XX, Pt.I,
pp. 1 19-132.

Geol. and Nat. Hist. Surv. of
Minnesota, Bull. No. 8.
Ont. Bur. Mines, Vol. XIV, Pt. I,
p. 257-

Ont. Bur. Mines, Vol. XV, Pt. I.

3. Bell, R

4. Ingall, E. D

5. Miller, W.G

6. Bowen, N.L

7. Lawson, A.C

8. Smith, W. N

9. Silver, L. P

PORT ARTHUR TO WINNIPEG VIA CANADIAN
NORTHERN RAILWAY.

W. L. Uglow.

INTRODUCTION.

The excursion over the Canadian Northern railway from
Port Arthur to Winnipeg affords an opportunity of seeing
an unusually complete Pre-Cambrian section. Within
this distance of 230 miles (370 km.) every Pre-Cambrian
series that had been differentiated in the Lake Superior
region is exposed to a greater or less degree. In addition,
the base of the section is formed by the Coutchiching
series, one that is rare in other localities, and which is
claimed by those who have studied it specially, to be even
older than the Keewatin. The area also contains, in
exposures of fossiliferous Lower Huronian limestone, the
oldest known records of life.

A few broad topographic features should be mentioned at
the outset. Two chief types of topography are well repre-
sented: the rocky lake country, and the alluvial plain.
Generally speaking, the former occupies the eastern part
of the region traversed, although the first 25 miles (40 km.)
of the trip are across the post-glacial flood-plain of
Kaministiquia river. West of Rainy lake, rock exposures
and hills are rarely seen, and the level country passed
through is in part the alluvial plain of Rainy river, and in
part the bed of glacial Lake Agassiz, (12) which continues
to Winnipeg.

The most recent classification of Canadian Lake Superior
geology is that by Dr. Andrew C. Lawson in his new report
(6) on the Rainy Lake region. For purposes of reference
his table of formations is reproduced below, in full. What
are believed to be the equivalents of the various series in
the nomenclature of the International Committee and of
the United States Geological Survey are included in
parentheses.

Algonkian fKeweenawan (Keweenawan).

(No equivalent). i Unconformity.

[Animikie (Upper Huronian).

Eparchacan Interval — Unconformity between the Middle and
Upper Huronian.

Algoman (granites intrusive into the
Lower and Middle Huronian).
Irruptive contact.
Seine series (Middle Huronian).
Unconformity.

Steeprock series (Lower Huronian).
! Unconformity.

Laurentian (Laurentian).
Irruptive contact.

Ontario Keewatin (Keewatin).

(Keewatin) Coutchiching (No equiva-
lent?).

Archaean

(No equivalent)

A short quotation (6) will explain Dr. Lawson's method of
subdividing the series below the Cambrian: "Upon the
vast peneplain resulting from degradation during the
Eparchaean Interval were deposited the Animikie sedi-
ments. The Animikie is thus separated from the
Huronian by an enormous interval of geological time.
On the far side of that interval the earth's crust was affected
by plutonic activities, involving the Coutchiching, Keewatin
and Huronian similarly, which have not recurred in the
region so far as is known on the near side of that interval.
In other words, the Huronian is allied in its geological his-
tory with the Coutchiching and Keewatin, and is part of
the Archaean, while the Animikie (Algonkian) is allied with
the Palaeozoic."

In order to complete the geological sequence exposed
along the Canadian Northern railway, there should be
mentioned an outcrop of Richmond fossiliferous lime-
stone (Ordovician) , found by Dr. Lawson, about six
miles (9-6 km.) west of Fort Frances, and believed by
him to represent an outlier of the Palaeozoic rocks more
abundantly exposed in the valley of the Red river in
Manitoba.

ANNOTATED GUIDE.
(Port Arthur to Iron Spur.)

Miles and
Kilometres.

o-o m. Port Arthur — Altitude 607 ft. (185 m.).
o-o km.

3- 0 m. Fort William — Altitude 612 ft. (186 m.).

4- 8 km. These two cities, commonly known as the* 'Twin

Cities," are located at the head of the Great
Lakes system of navigation. The rocks under-
lying Port Arthur and Fort William consist of
apparently flat-lying Animikie sediments (slates,
indurated shales, cherty dolomites, etc.) and
Keewenawan diabase sills. The characteristic
topography produced by the erosion of this
group of rocks can be seen in the islands and
shores of Thunder bay. The flat-topped, steep-
sided outlines of these hills are produced by
cappings of diabase which have protected from
erosion the underlying sediments. In some
sections more than one sill may be observed.

Leaving Port Arthur, the train takes a south-
westerly course across the post-glacial flood-
plain of the Kaministiquia river to the towns
of Fort William and Westfort. A short distance
to the south of Westfort, McKay Mountain rises
to a height of 1,600 feet (488 m.) above the
sea, and exhibits pronounced mesa-like outlines.
The horizontal attitude of the sills and Animikie
sediments, as well as the vertical columnar
jointing of the former, may be readily observed
from the train. After passing Westfort, the
soft, rounded outlines and roche montonee
topography characteristic of the southern part
of the Archaean terrane, appear in the far dis-
tance to the north and northwest.

23-4 m. Kakabeka Falls — Altitude 912 ft. (278 m.).

37-7 km. Up to this point, and for some distance beyond,
the railway traverses the flood-plain of the
Kaministiquia, and the total absence of rocky
hills near at hand is a striking feature . Near
the station, however, the Kaministiquia drops
a short distance over Archaean granite-gneiss, and

Kilornetres E ^° ' 8 km-) ^e^OW A°ws down a

low gradient to the great falls, which are over
a cliff of horizontal Animikie indurated shales,
150 feet (45-7 m.) high. The Animikie-Ar-
chaean unconformity is not well exposed, al-
though traces of a basal conglomerate are found
plastered on horizontal surfaces of the granite
gneiss. But the structural discordance between
the comparatively undisturbed Animikie strata

Animikie indurated shales, Kakabeka falls.

and the highly sheared Keewatin greenstones,
which outcrop a short distance away, is sufficient
proof of uncomformable relations.

From this locality westward
82-3 m. Kashaboiwe. to the vicinity of Kashaboiwe
132 • 5 km. a belt of Keewatin greenstone

and felsite schists is followed. In association
with this belt are lenses of iron formation
which constitute what is known as the Mattawin
iron range. The iron-formation is generally
banded in character, and deposits of clean ore

Kilometres occur °^ koth t^ie magnetite and hematite types.

The granite-Keewatin contact is crossed just
west of Kashaboiwe, and the greyish-white
granitic hills are a prominent topographic fea-
ture from this point to near Huronian.
97-1 m. Huronian. — The next 25 miles (40 km.) to
156-2 km. Kawene station afford an excellent opportunity
to observe the intrusive relations between an
Archaean granite-gneiss and a distinctly sedi-
mentary series. Sufficient detailed work has
not yet been done in this part of the region to
definitely correlate these rocks, but, in all prob-
ability, they are the Algoman granite and the
Seine sedimentary series, which will be examined
in detail at Iron Spur. An excellently developed
contact breccia continues with abundant ex-
posures for the whole distance, and may be
readily observed in a general way while en route.
12 1 • 6 m. Kawene. — At Kawene the contact swings south
195-7 km. of the track, and from here to mile post 126
excellent exposures of the Seine series occur on
both sides. At this mile post, the contact is
again crossed, and the Algoman granite con-
tinues to Iron Spur.
123-8 m. Iron Spur — Altitude 1,400 ft. (427 m.) From
206-4 km. this point a trip is taken three miles (4- 8 km.)

along a spur line to the site of the Atikokan iron
mine to observe the irruptive contact between
the Algoman granite and the Seine series, and
to examine the high-sulphur iron ore-body.

GEOLOGY OF THE VICINITY OF IRON SPUR.

General Statement.

The general elevation of the country surrounding
Iron Spur is between 1,300 and 1,500 feet (396 and 457 m.)
above sea-level, or from 700 to 900 feet (214 to 275 m.)
above Lake Superior. The outstanding features of the
physiography are the low rounded hills that characterize
the Pre-Cambrian in this part of Canada. The intervening
areas consist occasionally of glacial drift, but more usually
of alluvial material, forming what are commonly known as
muskegs.

The geological series represented in the vicinity are,
in descending sequence, according to the nomenclature of
Dr. Lawson:

f Algoman

Irrnptive contact.
Archaean { Seine series

Unconformity.
{ Keewatin.

Keewatin.

Exposures of this formation are rather rare in the imme-
diate neighbourhood, but occur a short distance north of
Atikokan river as part of a N.E.-S.W. belt. The rock
types represented are greenstone, gabbro, felsites (quartz-
porphyries) and their schistose equivalents.

Seine Series.

This consists of a group of rocks, which typically con-
sists of dark-coloured micaceous quartzites, quartz slates
and greywacke slates, grading into sericitic schists. Their
appearance, both on fresh and weathered surfaces is
decidedly sedimentary. In other localities they are found
to be unconformably above the Keewatin and Laurentian.

Algoman.

This is primarily a biotite granite of medium to coarse-
grained texture. It varies between granite and syenite types,
and usually contains phenocrysts of acid feldspar. Previous
to the summer of 191 1 it was mapped by Canadian geolo-
gists as part of the Laurentian. But now, in this locality,
a small oval-shaped area is differentiated, owing to the fact
that it intrudes a well-defined, water-deposited series.
It is believed that a considerable part of the rocks mapped
as Laurentian in this part of the province is really younger
than the Seine series and therefore of Algoman age.

The area was mapped in 1897 by W. Mclnnes and the
late W. H. C. Smith for the Geological Survey as part of
the Seine River sheet. Since that time Dr. A. P. Coleman
and others have visited the region in connection with
studies of the Lake Superior iron ores. The most recent
work in the area was done by Dr. Lawson during a visit

to this locality in the summer of 191 1, and by the late
Dr. J. D. Trueman in the early summer of 1912.

PARTICULAR DESCRIPTION OF POINTS TO BE VISITED.

Ore-body at the Atikokan Iron Mine. — The iron
ore deposit occurs in a rocky ridge running approximately
east and west, just north of the track and about 2-75

Open cut, Atikokan iron mine, Iron Spur, Ontario.

miles (4-4 km.) from the beginning of the spur. The
rocks in the vicinity of the mine are very imperfectly
exposed. The ridge itself is isolated, being bounded by
a muskeg on the south, and separated by a valley from a
ridge of Keewatin greenstones to the north.

The ore is magnetite, rather freely supplied with sulph-
ides, chiefly pyrite, but also including traces of chalcopy-
rite. It occurs as a series of overlapping lenses, separated
from one another by walls of greenstone, and bounded on
the north side by a wall of highly sheared acidic rocks.
Associated with the ore and interlaminated with it, are
beds of greyish-white chert and dark green slate. In
places along the strike, especially near the east end, narrow
beds of ore, chert and slate may be seen interlaminated
with each other. The ore-bodies and associated rocks have
a common strike and dip, the later varying from vertical
to 6o° north.

The following account of the origin of the ore-body is
given by Dr. Lawson in a forth coming report of the
Geolical Survey of Canada, and on account of its dissimi-
larity to other interpretations is worthy of quotation
almost in toto:

"Iron ores occur either at the contact or close to it where
there is no conglomerate. The ore and the conglomerate
thus appear to be in a certain sense complementary features
of the base of the Seine series. It is interesting to note
in this connection that the pre-Seine surface of the Keewatin
greenstones, where it emerges from beneath the Seine
series, is commonly heavily charged with carbonates
(including siderite or ankerite) and limonite. This
condition in some sections obtains for several hundred
feet away from the contact, and with little question it
represents the effect of the weathering of the Keewatin
surface in pre-Seine or early Seine time. It suggests a
supply for the iron ore that is found in workable bodies
and in less important prospects along the line. The
concentration may have been effected in bogs in early
Seine time, a possibility which harmonizes with the absence
of conglomerate at such points along the contact; or it
may have been concentrated by underground circulation
after the burial of the weathered and iron-rich surface
by the Seine sediments."

Particular interest attaches to this particular occurrence,
because of the successful attempt of the company to use
an ore which is not only hard but also markedly rich in
sulphides.

The mine has a good surface equipment, and the company
owns an up-to-date blast-furnace at Port Arthur which
was designed and erected primarily for the treatment of

the high-sulphur Atikokan ores. Before being smelted
these ores are specially treated to eliminate the sulphur,
so far, with remarkable results.

Irruptive Contact of the Algoman Granite with
the Seine Sedimentary Series. — The phenomena to be
observed in this connection extend from a point on the
railway spur one eighth of a mile (o-2 km.) from the main
line along the spur to the main line, and then for an eighth
of a mile (o-2 km.) westward along the main line. On
returning from the iron mine, the following points in
connection with the intrusion can be noted in the order
given.

1. Dykes and stringers of granite cut the dark-coloured,
anamorphosed phase of the Seine series, and frequently
traverse it across the bedding.

2. Angular to rounded fragments of the altered Seine
rocks are abundant within the granite mass.

3. Assimilation of these inclusions by the intrusive is
shown by its abundant content of hornblende and general
adoption of a basic phase near the intruded series.

4. A short distance from the contact, the Seine rocks
resemble a dark-coloured gneiss, rich in quartz and biotite
with stringers of lighter-coloured, more or less feldspathc
material.

5. The passage from this anamorphosed variety through
a less altered one to the normal phase may be well followed
by observing the exposures in two railway cuts, about
an eighth of a mile (0-2 km.) along the main line and just
west of the section house. The character of the anamor-
phosed Seine series should be especially noted in order that
it may be compared with that of the Coutchiching series
in the Rainy Lake area.

ANNOTATED GUIDE (Iron Spur to Atikokan).

After leaving Iron Spur occasional exposures of the Seine
series, separated by stretches of muskeg occur on both
sides of the line. The valley of Atikokan river follows
rather closely from the crossing just west of Iron Spur.

Miles and
Kilometres.

131 -6 m. Hematite — Altitude 1,360 ft. (415 m.)

211-9 km. From this point westward to Atikokan, the
railway marks approximately the contact of
the Seine with the Keewatin group. The
latter stands out in much weathered exposures
of greenish-coloured schists in the hills just to
the north of Atikokan river. To the south
and usually in the rock-cuts along the railway
may be seen the quartzites and quartz slates
of the Seine series. The iron formation of the
Atikokan range which outcrops at intervals
on both sides of the track is probably an exten-
sion of the ore-bodies northeast of Iron Spur.
Half-way between mile posts 139 and 140,
there seems to be an actual contact between
the Seine series and the Keewatin but no trace
of a basal conglomerate could be found. With
the exception of a short space just east of mile
post 141, occupied by Keewatin greenstones,
exposures of the Seine series continue more or
less intermittently to Atikokan.
142 -4 m. Atikokan — Altitude 277 ft. (389 m.). From

229-5 km.this point a side excursion occupying half a day
is taken to Steeprock lake to examine the foss-
iliferous limestone and the structural features
of the Steeprock sedimentary series of the
Archaean.

GEOLOGY OF THE VICINITY OF STEEPROCK

LAKE.

General Description.

The physiographic features of this region are typical of
those in the southern part of the Pre-Cambrian terrane.
The rocky lake country, which is here well exemplified,
presents the character of a peneplain. Regarded on a
large scale, it is remarkably flat and devoid of prominent
elevations, but, when considered in detail, the surface
is extremely uneven and hummocky.

The general geology of the region was partially worked
out by Dr. Lawson for the Geological Survey in the summer

of 191 1, and on his report (7), recently published as a mem-
oir of the Survey, is based the following description.

The only rocks known in the area to be visited are those
of the Keewatin, Laurentian, Steeprock, and Seine series.
The position of the Steeprock series, well down in the Pre-
Cambrian, is of interest for the reason that the limestone
of which it is chiefly composed, is fossiliferous.

Keewatin. — This is the oldest group in the region and
consists chiefly of felsites (quartz porphyries), gabbros,
diabases, greenstones, and their schistose equivalents, as
well as occasional exposures of tuffs and agglomerate
schists. The strike of the schistosity varies from place to
place, but seems in a general way to accord with the contour
of the lake shore.

Laurentian. — This is primarily a medium-grained horn-
blende granite gneiss, showing only a slight foliation in
the Steeprock area. Near its contacts with the Keewatin,
it not only holds as inclusions large fragments of the older
series, but itself becomes quite basic, and grades into a
type closely resembling typical Keewatin hornblende
schist. In places, however, very sharp contacts of the
two series in their normal phases are exposed. On account
of its somewhat bleached appearance, and of its association
with much sheared varieties in neighbouring localities, the
series is correlated with the Laurentian.

Steeprock Series. — The rocks thus designated include
the following formations in descending order:

4. Green schists, evidently of detrital origin, traversed
by dykes and flows of diabase and diorite.

3. Volcanic ash, highly pyritiferous, schistose rock,
often containing fragments of limestone and black cherty
material.

2. Limestone, dolomitic to sideritic, and usually weather-
ing brown. The exposures at the sharp bends in the
shore-line of the lake are a brecciated variety, consisting
of angular fragments of limestone, black chert, and typical
Keewatin rocks.

1. Basal conglomerate, usually fine-grained, and fre-
quently of the nature of a quartzite or arkose.

The rocks of the series are almost in a vertical attitude,
the prevailing dips being 700 to 900 S.W. The series is
tentatively correlated with the Lower Huronian.

Seine Series. — Quartzites and quartzose slates of the
normal type, striking almost east and west, occur some

distance south of the lake, and along the Canadan Northern
Railway line in the vicinity of Atikokan.

Structure of the Area. — A good partial cross-section
of the Steeprock series is exposed along a line from the
west side of Strawhat lake to the east side of East bay.
In this section, a twofold repetition of the same set of
beds in reverse order is evident. The general strike is
N.W.-S.E. On the east, the conglomerate is in visible
contact with the Laurentian, while on the west it rests on
the Keewatin basement. The structure which has been
worked out for the area by Dr. Lawson is that of a simple,
closely folded syncline, whose axis is parallel to East bay,
and whose trough covers the contact of the Laurentian
and Keewatin.

In contrast with the folded condition of the Steeprock
series is the uniform monoclinal attitude of the Seine
quartzites and quartz slates. This stratigraphical and
structural relationship indicates that the folding, which
involved the Steeprock series as a sharp trough sunk
down into the older Archaean, had taken place anterior
to the deposition of the Seine series. It is therefore inferred
tentatively that the Steeprock series is older than the Seine
series.

The distribution of the Steeprock series and of its lime-
stone and basal conglomerate members, as far as they have
yet been differentiated from the Keewatin, is shown on
the accompanying map. The exposures in the southwest
corner on Seine river are a brownish calcareous schist,
not unlike that on the south shore of Falls bay. They are,
however, very closely associated with Keewatin felsites,
and may be either Keewatin in age or infolds of the Steep-
rock limestone.

The areal geology, indicated on the map, is only approxi-
mate, as detailed surveys have not yet been made.

Progress of Exploration. The geology of the area, on
account of the features of especial interest which it presents,
has received considerable attention from the Geological
Survey of Canada and other sources. In 1891, H. L.
Smyth (10) published an interesting set of results obtained
from an examination of the area. W. Mclnnes and the late
W. H. C. Smith (4) of the Survey mapped the region as
part of the Seine River sheet in 1897. Dr. A. P. Coleman
visited the area and published an interesting account of the
geology in 1898 (2). In 191 1, Dr. Lawson spent some time

C3.

'Seine River

Geological Survey, Ca.na.da

Steeprock Lake , Rainy River District

Legend

Ke ween a. wan

Diabase

Upper Huron ian

Seine series

Other members

Limestone and
basal conglomerate

Laurent /an

granite and granite gneiss

t Keewatin

Miles

Kilometres

0/2; 2 3 4- 5 fi 7 8

in the neighbourhood, and in his report are embodied the
results of the most recent work.

PARTICULAR DESCRIPTION OF POINTS TO BE VISITED.

Leaving the train at the station, a path is followed for
2-6 miles (4-2 km.) to Steeprock lake. At three-fifths of a
mile (1 km.) from the station the first rock exposures are
seen. They consist chiefly of Keewatin felsites, quartz-
porphyries, and their derived schists, with which are asso-
ciated, however, small lenses of a quartz conglomerate
which may be infolds of the base of the Seine series. Ex-
posures continue for about a mile (i-6 km.) farther, and
are mostly of Keewatin acidic and basic types, although
occasional small outcrops have a remarkably sedimentary
aspect.

After embarking in the boats a straight course is taken
to Jackpine point. On the left-hand shore are hills of
Laurentian granite gneiss, while on the right Keewatin
felsites and felsite schists, cut by dykes of post-Keewatin
diabase, are exposed to view. At the north end of Falls
bay a high brown bluff, consisting chiefly of the brecciated
phase of the Steeprock limestone, stands out bcldly.
Just as Jackpine point is reached a glimpse of Steep falls
to the northeast may be obtained.

Gross-section of the Keewatin and Steeprock Series
on the South Shore of Falls Bay. — In walking over this
section from west to east, the Keewatin rocks are first
noticed on Jackpine point where a schistose pyroclastic
is splendidly exposed. The fragments are of the same
material as the matrix, and although elongated in the
general direction of the cleavage are not schistose like it.
East of this are exposures of typical hornblende, chlorite,
and felsite schists.

The basal conglomerate of the Steeprock series is well
exposed next on a glaciated surface which extends for 150
feet (46 m.) across the strike (N 400 W). It should be
noted that the pebbles are chiefly quartz and granite, with
a few smaller ones of Keewatin diabase and greenstone.
To the east of this is a brown calcareous schist with lenses,
at times a foot (0-32 m.) thick, of ferruginous limestone.
This is all of the western limb of the Steeprock limestone
that is exposed on the south shore, but it is believed that
35069—4

more of the formation and also a bed of volcanic ash occupy
the depression in which the creek flows.

East of the creek are green schists of detrital origin
traversed by sheet-like masses of diabase and diorite,
which may be dykes or flows and which are younger than
the Steeprock series. With these intrusions there seems
to be associated diabase dykes which cut the granite and
greenstone in such a way that they apparently represent
the orifices through which the larger masses found their
way to their present position.

Fossiliferous Limestone at Point No. 1. — By crossing
in an easterly direction to a steep brown bluff, the first
exposure of the limestone in the eastern limb of the syncline
may be examined. The contact with the older rocks is
not exposed here, but lies under the drift in the depression
just to the east. An example, on a small scale, of the
deformation which the formation once suffered, may be
seen at the western corner of the point. The original
bedding and joint-planes of the limestone are rendered
visible by the abundant development of lime-silicate
minerals along them, which have weathered into relief.
A small exposure of a calcareous green schist probably
developed from the limestone may be seen also at this point.
The attitude of the beds should be observed.

The fossils are located chiefly at the southern corner of
the bluff, and are quite abundant, especially near the waters
edge. Atikokana lawsoni (15) seems to be the main
species represented at this point. It is one of a group of
organisims related to the sponges. Both silicated and
calcareous varieties occur.

From Point I a southeasterly course is taken to Point No.
2, about half a mile (o • 8 km.) distant. Along the route bold
Laurentian hills easily distinguishable by their pale pink
weathering, may be seen to the east. Dark-coloured
patches occur scattered here and there through the gneiss.
In some cases there are dykes similar to those associated
with the crystalline traps of the Steeprock series, while in
other cases there are detached masses of the intruded
Keewatin engulfed by the granite when still in a viscous
condition. The Laurentian-Keewatin contact zone is
approximately in the trough occupied by the lake. A
narrow fringe of limestone which may be distinguished by
its brown colour, extends almost continuously along the
east shore between the two points.

On the west side of the bay, the geology is quite different.
The high ridge which roughly parallels the bay consists
chiefly of the crystalline traps (diabase and diorite) and
associated clastic green schists of the Steeprock series.
Along the waters edge, directly west from Point No. 2,
is a small exposure of the volcanic ash of the same series.

Fossilferous Limestone and Unconformable Con-
tact of the Steeprock Series with Laurentian at
Point No. 2. — At this locality, the attitude of the lime-
stone beds is well marked, and may be best seen in the
bay at the south end of the bluff. From this bay a trail
leads a short distance up the hill over granite, and then
swings northwestward across the unconformity. A con-
tinuous section at right angles to the contact is exposed.
The granite may be followed westward from a comparatively
unaltered phase through 45 feet (13-7 m.) of a schistose,
gritty, bleached variety to the Steeprock series basal
j conglomerate. The transition is not a sharp one. The
j conglomerate, which contains small pebbles, chiefly of
quartz and fine-grained granite, is from 5 to 8 inches
(12-7 to 20 -3 cm.) thick and is followed in the direction
of the limestone by 50 feet (15-2 m.) of thinly bedded
impure, quartzitic and slaty rocks. The limestone is in
sharp contact with these. The nature of the uncon-
formity should be carefully noted in order that it may be
compared with that between the Laurentian and Seine
series to be seen on the Mine Centre trip.

Fossils are best seen on the face of the bluff near the
waters edge.

Fossiliferous Limestone at Trueman Point. — From
Point No. 2 the course is a direct southeasterly one up
the bay, with exposures of the basement complex on the
east and of the Steeprock series on the west.

A ledge on the eastern side of Trueman point, near the
narrow rock joining it with the main shore is the locus of
Dr. Lawson's original discovery of fossils . Two varieties
are to be found. They are quite abundant near the waters
edge, especially along the face of the bluff.

The contact of the limestone with the older rocks is
not exposed, but the fragmental formation between the
limestone and the granite gneiss may be seen on the side
of the hill just east of the southern landing.

In places the limestone is quite sideritic, and appears
as a thinly-banded, brown and grey rock, resembling a

35069— 4J

lean phase of the iron formation. This variety is exposed
near the centre of the west face of the bluff, where there is
a slide of talus material.

The attitude of the beds is well shown near the waters
edge, where there is an abundant development of the
lime silicates, which have weathered into marked relief.

Fossiliferous Steeprock limestone, Trueman point, Steep-
rock lake, Ontario.

A dyke of quite unaltered diabase cuts the Laurentian
about 500 feet (152 m.) north of the northern landing, and
probably represents a vent through which some part of
the sills or flows in the Steeprock series reached their
present position. Numerous basic, dyke-like masses cut
the granite in this neighbourhood.

Brecciated Limestone at Elbow Point. — From True-
man point a direct return trip is made to the northwest
end of Elbow point, where a breccia made up of angular
fragments of limestone, black chert, and Keewatin felsite
and greenstone, cemented together by crystalline limestone
is well exposed. Interbedded with this are layers of a
more or less pure limestone. As pointed out above, these
brecciated phases are chiefly exposed at the sharp bends
in the shore-line.

After examining this locality, the return journey is
made to Atikokan.

ANNOTATED GUIDE.

(Atikokan to Mine Centre).

kilometres Beyond Atikokan the railway proceeds in a
general way down the valleys of the Atikokan
and Seine rivers for 35 miles (56-4 km.). The
Seine series-Keewatin unconformity, with the
younger series on the south side, follows with
minor irregularities the bed of Seine river almost
as far west as Mayflower. Occasional exposures
of the Seine series are seen along the railway,
except in two small stretches from mile posts
147 to 149, and from 159 to 161, where the
contact swings south of the railway, and parts
of the Keewatin belt are crossed.
i6o-om. Banning — Altitude 1,256 ft. (383 m.). In
257-8 km. this vicinity, diamond-drilling for iron ores has
been carried on recently, but the results have
not been highly satisfactory. The outcrops,
which are of a hard iron formation in associa-
tion with Keewatin greenstones, lie close to
the railway and constitute probably part of
the western extension of the Atikokan iron
range.

After passing mile post 161, splendid expo-
sures of the Seine schists and slates may be
seen in the cuts on both sides of the railway
as far west as Mayflower.
164-7 m. At this point a stop of about fifteen minutes
264-9 km. is made to examine a case of post-glacial faulting
(8) in the Seine series. The exposure is just

KibmSres. a few feet south of the track> and the chief
points to be noted are: —

1. The nature of the rocks — phyllitic slates.

2. The strike and dip of the bedding or
cleavage planes.

3. The reverse or overthrust character of
all the faults.

4. The constancy of direction of the glacial
striae, and their extension on both the upthrow
and downthrow sides to the very edge of the
fault plane.

5. The sharpness of the fault scarps.

6. The coincidence of the fault-planes with
the cleavage of the slates.

7. The absence of fault breccia or slickensides.

8. The absence of any horizontal component
in the differential movement.

9. The number of fault scarps (24 in 66 feet
(20 m.) across the strike), and their average
height.

10. The presence of a transverse fault.

11. The presence of one stepped scarp.

For reasons explained in his paper (8)
Dr Lawson ascribes the faulting not to orogenic
forces, but rather to the play of compressional
and relaxational forces resulting from change
of temperature or load. He cites other examples
from geological literature of such faulting,
and concludes that it is peculiar to slaty rocks.

165-0 m. Mayflower. — From a short distance west
265 km. of Mayflower to milepost 169, the Seine-Kee-
watin unconformity is again south of the railway,
and Keewatin rocks are exposed on both sides.
For the succeeding eight miles (12 -8 km.) the
railway runs in a northwesterly direction and
affords a partial section of the Seine series,
through the quartzites and slates to the basal
conglomerate, which is excellently exposed
just west of Mathien. (176 m., 283 km.)

The remainder of the trip as far as Mine
Centre is through a drift-covered area underlain
by the Keewatin which outcrops only at inter-
vals.

Miles and
Kilometres.

190-5 m. Mine Centre. — Altitude 1,190 ft. (363 m.)

306-5 km. From this point a trip is taken to the site of
the Golden Star mine on Bad Vermilion lake
to examine the following points: an occurrence
of limestone in the Keewatin series; the contacts
of the Seine series with the Keewatin, of the
Seine series with the Laurentian, of the Laur-
entian with the Keewatin, and of the anor-
thosite gabbro with the Keewatin ; and the litho-
logical characteristics of the rocks of the various
series.

! GEOLOGY OF THE VICINITY OF MINE CENTRE.

GENERAL DESCRIPTION.

The area to be visited has the typical physiography of
the southern part of the Pre-Cambrain terrane, and is
not essentially different from that of the Steeprock lake
area. Bad Vermilion lake is six miles (9-6 km.) long in
a direction a few degrees south of west, and follows in a
general way the strike of the Keewatin schists. It con-
tains comparatively clear water, and has depths of 400 feet
(122 m.) and over in places. The bold, glaciated rocks
on the southern shores stand out prominently.

The general geology of the area is identical with that
of a great part of the region just passed through. The
particular interest attached to this locality is due to the
remarkably well exposed contacts which lie within 500
feet (152 m.) of the old mine. The geological succession,
in descending order, is: —

Archaean.

Seine series.

Unconformity.
Laurentian.

Irruptive contact.
Anorthosite (Keewatin?).

Irruptive contact.
Keewatin.

Keewatin. — Typical rocks of this series are well exposed
in the area, and consist of greenstone, green schist, diabase,

agglomerate schist, felsite, felsite schist and a limestone
and chert formation.

Anorthosite. — This is a highly feldspathic saussuritized
gabbro or anorthosite which is areally disposed like a collar
about a central heart-shaped boss of granite. It is clearly
intrusive into the Keewatin, presumably in the form of
laccolithic lens which tapers westward. The intrusion
took place probably before the severe deformation of the
Keewatin, for the gabbro is itself intensely sheared locally.
The rock contains in places crystals of anorthite 10
inches (25 cm.) in diameter.

Laurentian. — This consists of a medium to coarse-
grained, light-coloured, biotite granite, locally poor in
biotite, and thereby grading into alaskite. It is intrusive
into the anorthosite, as well as into the Keewatin, and it
is believed, from the areal relations of the rocks, that it
attained its present position by arching up the lenticular
anorthosite sheet.

Seine Series. — Within the area under discussion the
Seine series is represented chiefly by a great thickness of
basal conglomerate which grades upward into typical
quartzites and slaty schists. The conglomerate contains
a large amount of debris derived from the waste of Keewatin
rocks, but the pebbles and boulders, which are usually
well water-worn, consist chiefly of different varieties of
granite with a subordinate proportion of greenstone,
quartz porphyry and dark coloured chert pebbles.

Particular Description of Points to be Visited.

The Keewatin Series seen en route to the Mine. —

A trail about half a mile (o-8 km.) long leads from Mine
Centre station southwest to the shore of Bad Vermilion
lake. Two ridges of Keewatin rocks are crossed by this
trail. One, just south of the village, consists of highly
schistose felsites and quartz porphyries, while the other,
which borders the north shore of the lake, is made up of
quite basic rocks, which are greatly deformed, owing, no
doubt, to their proximity to an area of intrusion.

The lake is crossed in boats to the road leading to the
burnt remains of the Golden Star mine. Here Keewatin
greenstones and felsites are exposed on all sides.

A trail, leading directly south across the hill, is followed
for about 300 feet (914m) to where it joins the mine road.

On top of the hill may be seen excellent exposures of
the Keewatin, consisting of calcareous schists with lenses
of ferruginous limestone, and a band of schistose volcanic
agglomerate. The road eventually leads to a well, which
is the starting-point for the first side trip.

Limestone Bands in the Keewatin. — From the well,
a path 500 feet (152 m) long, marked by yellow flags,
leads to an exposure of Keewatin limestone. On the
right hand side of this path, before coming to the limestone
may be observed ridges of grey-green weathered felsite,
much fractured as a result of igneous intrusion.

The limestone occurs in a series of bands from a few
inches to a foot thick, which are interlaminated with
discontinuous bands of chert and chert agglomerate.
The total width of the formation is about 10 feet (3.2 m),
and it can be traced along the strike for 275 feet (84 m).
The strike is N 650 E, and the dip 500 to 6o° N. W. The
limestone is a highly granular, medium-grained variety,
containing an abundance of minute crystals of brown
mica scattered through its mass. An analysis shows
that it contains only o . 35 per cent MgC03. Resting upon
the limestone is a two foot (0.61 m) bed of brecciated
chert, which grades upward into a porpyhritic dense
felsitic lava. The proof of the contemporaneity of the
limestone and the felsite is important in discussing the
relation of the limestone to the Seine series.

Unconformable Contact of the Seine Series with
Keewatin Felsite. — The mine road (marked by white
flags) is next followed in a southeasterly direction for 200
yards (183 m), up a hill of felsite cut by basic igneous
dykes. The ruins of the mine, which was destroyed by the
Rainy Lake fire of three years ago, may be seen on the right.
A path marked by blue flags, leading to the left is then taken.
It affords an opportunity of observing the contour of
the felsite, and leads to the contact of the felsite with the
Seine series near the top of the ridge. The character of
the felsite should be noted in order that the pebbles in
the conglomerate may be compared with it, and the contact,
which is located by red flags, should be followed a short
distance to observe the nature of the basal conglomerate.

Irruptive Contact of the Laurentian with the
Keewatin. — The white flag route is followed for a
short distance to where it is joined by another road from
the west. At this point, a series of green flags marks

5»

the Laurentian Keewatin contract. The exposures are
not good, but the two formations may be observed within
five feet (1.5 m) of each other, and fine-grained dykes
may be seen traversing the felsite. Near the contact
the granite is characterized by a comparatively fine-
grained texture. On the main road from Mine Centre
to Shoal lake, the granite holds angular inclusions of
the nearby Keewatin rocks.

Unconformable Superposition of the Seine Series
upon the Laurentian. — A few yards farther along the
white flag route, the contact of the Seine and older rocks
crosses the road. To the right (southeast) the contact of
the basal conglomerate with the granite is marked by
brown flags. The lower 15 feet (4.6 m) of the conglo-
merate is composed of a yellowish grit, or arkose, formed
by the disintegration and re-cementing of the granite. The
two rocks are notably similar. At a short distance from
the contact the granite assumes its normal pale pink
colour and granitic texture. By walking 200 feet (61 m)
southeast along the unconformity the relations and cha-
racters of the two formations may be observed more fully.

A few quotations from Dr. Lawson's report (6) will
serve to draw attention to some of the salient features: —
"The bottom portion of the conglomerate formation,
while very clearly detrital, is neither water-worn nor far
transported. The fragments which compose it are regular
detritus of a desert alluvial slope. Where it rests upon
the granite, the detritus is nearly all derived from the
underlying granite, blocks of granite being enclosed in
a coarse quartzitic arkose matrix; and where it rests
upon the nearby Keewatin, it is nearly all derived from
the underlying rocks of that series, but with considerable
quartz in some parts of the matrix. This facies of the
accumulation is very evidently the same as that described
elsewhere under the name of fanglomerate.

"Since the fanglomerate is without doubt a subaerial
formation it grades up into a conglomerate in which the
boulders and pebbles are well water-worn, it seems a
fair inference that the conglomerate represents a gravelly
flood-plain rather than the beach of a trangressing sea.
If this be true, then in a general way the distribution of
the conglomerate as outlined on a general geological map
of the region indicates the course of a river."

This unconformity should be compared with the
Laurentian-Steeprock contact visited at point No. 2.

The Anorthosite and its contact with the Keewa-
tin.— This contact is exposed on the south shore of Bad
Vermilion lake about half a mile (o-8km.) west of the
Golden Star mill.

Dykes of anorthosite may be seen cutting the Keewatin
and small areas of the coarse-grained variety are exposed
near the end of the trail which leads to the top of the
ridge.

The Golden Star Mine. — The Golden Star mine re-
sulted from a prospectors' "rush" in Rainy Lake district
eighteen years ago. A well-equipped surface plant was
installed and underground workings totalling 3,500 feet
(1,065 m.) were carried to a depth of 537 feet (163m.).
The ore body, which was a quartz vein associated with
aplite dykes, carried values chiefly in gold, with small
amounts in silver and copper. The gangue was principally
aplite and ferrodolomite. All operations ceased thirteen
years ago (1900) and the plant was burnt in 1910 (16).

ANNOTATED GUIDE.

(Mine Centre to Bear's Pass.)

miSSetres After leaving Mine Centre, the railway fol-
lows the south shore of Turtle lake, and proceeds
almost due west for about 12 miles (19-3 km.).
The country is flat and, to a large extent,
swampy. Occasional exposures of Keewatin
rocks, greenstone, diabase, and green schist,
may be seen. A short distance north of mile-
post 195 is the location of the Olive gold mine,
a glimpse of which may be caught from the train.
The mine is an old one, having been opened up
at the time of the Rainy Lake gold rush, but
is at present inactive. A drift-covered area of
Keewatin rocks extends to about mileage 200-5
(323 km.).

200-00 m. Farrington — Altitude 1,154 ft. (352 m.).
322 • o km. In this neighbourhood rock exposures are rare.

Hills of the basement complex may be seen here

Miles and and there in the distance. Half a mile (o-8

Kilometres. . . v

km.) west of Harrington an area of Algoman
biotite granite gneiss, which continues to Bear's
Pass, is entered. The country underlain by
this formation is generally more rugged than
the previous 20 miles (32 km). A short distance
west of milepost 207, Keewatin rocks are again
seen, but the contact with the granite gneiss is
not visible in the immediate vicinity of the rail-
way.

207-3 m. Bear's Pass — Altitude 1,143 ft. (349 m.).

333 • 8 km. From this point a trip five hours in
length is taken in boats around the shores of
the eastern arm of Rainy lake for the purpose
of examining the Coutchiching series, and ob-
serving its relations to the Keewatin and the
Algoman granite and syenites.

THE COUTCHICHING SERIES ON RAINY LAKE

General Description.

The Rainy Lake area affords a typical example of the
rocky lake topography of the Pre-Cambrian shield. It is
part of that region investigated by Dr. Lawson in 1885-
1888 (5). The geology of this area was revised by the same
investigator in 191 1, certain important changes in correla-
tion being rendered possible by the improved accessibility
of the country and by the more advanced state of know-
ledge regarding Lake Superior geology in general. The
following descriptions and review of the geology are based
on the results of his recent work (191 1) (6). The geological
sequence of the rocks exposed is given below in descending
order :

[Algoman

j — Irruptive contact —

Archaean | Hornblende gabbro (Keewatin ?)

— Irruptive contact —

Keewatin ) ^ , •
r 4- u- u- Ontanan
Coutchiching J

Coutchiching. — This group of rocks consists of mica
schists, feldspathic mica schists, and evenly-laminated,

fine-grained gneisses. Their character throughout the
area is remarkably uniform. They are believed to repre-
sent in a highly anamorphosed condition the old sediment-
ary crust through which the Keewatin igneous rocks were
erupted and poured out as flows.

Keewatin. — The basic types, gabbro, diabase, diorite,
basalt, tuff, and their schistose equivalents predominate
in this district. They are metamorphosed to variable
degrees, some of the gabbros and diorites being quite un-
altered.

Hornblende Gabbro. — Thick sill-like masses of a
rather schistose gabbro occur in association with the Kee-
watin series. The predominant femic mineral is horn-
blende, but large idiomorphic crystals of basic feldspar are
abundant. Contacts with the Keewatin are exposed at a
number of localities, where the gabbro is seen to be clearly
intrusive into the Keewatin. The fact that it is wholly
confined to the Keewatin area suggests that the intrusion
is a sill or sills injected into the Keewatin prior to its
deformation and metamorphism.

Algoman. — This group consists of medium-grained
biotite granite and granite gneiss, with less important areas
of mica syenite, and mica syenite gneiss, which have in
this district developed a remarkably basic facies. On
account of the warm flesh to pink colour of the granite, of
the fresh biotite it contains and of the marked contrast
in the general appearance of the rock, with the highly
sheared Laurentian granites of Rice bay and other localities,
Dr. Lawson identifies this group with the Algoman.

Structure of the Area. — The stratigraphical relations
of the Coutchiching, Keewatin and Algoman groups are
well exposed on the shores of the lake, and may be seen at
different points along the route. An examination of the
strikes and dips of the Coutchiching as platted at different
points on the map shows that the formation is in the shape
of a large symmetrical anticline with the axis striking N.E.-
S.W. Locally around bosses of granite, the anticline
approaches a dome in form, with the planes of the Cout-
chiching dipping on all sides away from the granite. The
gradual passage of nearly flat-lying beds along the anti-
clinal axis to more steeply dipping ones vanishing under the
Keewatin belts on the east and west shores, may be easily
traced. No unconformity, other than an abrupt tran-
sition from the distinctly igneous rocks of the Keewatin

to the uniformly micaceous gneisses and schists of the
Coutchiching, is present at these points. The transition
marks a decided change in the conditions of rock formation.

Coutchiching mica schists dipping beneath Keewatin greenstone,
Rainy lake, Ontario.

The irruptive nature of the Algoman-Coutchiching con-
tact may be observed at several points to be visited. In
proximity to the contact, inclusions of previously schistose
Coutchiching are surrounded by the biotite granite, while
apophyses of the granite invade areas of Coutchiching.
In such localities, certain beds of the Coutchiching are
abundantly supplied with secondary aluminous silicates.

It is interesting to note that the figures which represent
the dips of the bedding planes away from the granite

bosses agree with the attitude of the contact plane between
the granite and the Coutchiching schists, this contact
being exposed in the face of cliffs that have various salients
and re-entrants. The anticlinal form of the mica gneisses
and schists is due to the intrusion of the Algoman batholith
which has simply arched them over itself to form a roof.
Dr. Lawson's conclusion is stated thus: "The Coutchich-
ing rocks are disposed in an anticline domed around an
intrusive mass of granite, and they pass on both flanks of
the anticline beneath the Keewatin".

PARTICULAR DESCRIPTION OF POINTS TO BE VISITED.

After leaving the train at Bear's Pass the route around
the shores of the lake follows in numerical order the small
numbers, I to 32 on the map.

From the station to 1, a partial cross-section of the
Keewatin, is exposed. The strike and dip of the schist
and the nature of the coarse-grained gabbro can be observed
Going southward along the shore between 1 and 2, the
transition from Keewatin hornblendic and chloride rocks
to Coutchiching micaceous schists, with about the same
strike and dip, may be seen, the latter dipping beneath
the former. From 2 to 4 the irruptive contact of the
Algoman biotite granite and the Coutchiching is well
exposed; the long narrow point at 3 affords a splendid
view of the contact breccia. The granite is pale pink
to white in colour, and somewhat fine-grained. The
shore line in this vicinity shows alternate outcrops of
Algoman and Coutchiching.

A landing is made at 4 to examine the contact between
the Coutchiching and the Keewatin. Here the micaceous
schists are markedly quartzitic and are beautifully plicated.
The contact with the rather massive Keewatin greenstone
is sharp, and the Coutchiching dips rather steeply under it.

From this point in a westerly direction to 8 an excellent
section is obtained across the Coutchiching formation
almost at right angles to the anticlinal axis. The shore
is followed closely, so that the attitude of the Coutchiching
beds may be noted. The steep southeasterly dips of the
formation to the east gradually flatten, until in the neigh-
bourhood of 5 and 6 they are nearly horizontal or locally
buckled. Here the locus of the anticlinal axis is reached.

From 5 west, the dip is in the opposite direction, that is,
to the northwest, and gradually increases to 450 or 500
The steep dips of 6o° to 750 on the eastern limb of the
anticline are nowhere seen on the western limb. Along
the shore near 7, the nature of the formation at a distance
from the intrusive granite and the attitude of the beds are
exposed to advantage.

From 8 to 9 the contact between the Coutchiching
and the Keewatin can be traced approximately. On the
left hand side the mica gneisses and schists, dipping from
250 to 450 towards the northwest, are well exposed. On
the right, the islands numbered 26, 25 and 22 consist of
typical Keewatin formations.

From 9 through Bear's Passage to 13, another section
is made across the anticlinal axis of the Couchiching.
Generally speaking, the dips change from northwest to
southeast through an intermediate, approximately hori-
zontal attitude. The intrusive granite, which is exposed
in actual contact with the Coutchiching from 10 to 1 1 is
a disturbing factor in this section. Near its margin, the
mica gneisses and schists strike roughly parallel to the
contact, and in all cases dip away from the granite boss,
as if they had been arched over its surface at the time of
the intrusion. A gradual increase in the angle of dip is
observed from 12 to 13, until, at a maximum of about
700 to the south-east, the Coutchiching disappears under
the more massive rocks of the Keewatin. The actual
contact is not exposed here.

From 13 to 14 a belt of Keewatin schist with a steep
southeasterly dip is crossed to another band of Coutchi-
ching, also dipping steeply to the south east. This
Keewatin belt is interpreted as the eroded remnant of an
appressed synclinal trough, overturned towards the
southeast, and pitching to the northeast. In this second
or Shelter Cove belt of Coutchiching, the series is repre-
sented by quartz slates rather than the metamorphic mica
schists. At 15 a good exposure of the Coutchiching in an
almost vertical attitude may be seen. Farther east, it
passes again under the Keewatin.

The course now leads directly to Bear's Passage and
along the left hand shore from 16 in a northwesterly
direction. An almost continuous outcrop of Algoman
granite with large inclusions of mica schist follows the shore
to beyond 17, and may be observed in passing.

The granite-Coutchiching contact is crossed between
17 and 18. At the latter point, there is a good exposure
of a basic facies of the Algoman syenite intruding the
Coutchiching, which dips away from it on all sides. The
contacts are well exposed.

The shore line is closely followed to the railway
crossing, and typical exposures of Coutchiching, abund-
antly supplied with secondary crystals of the aluminous

Inclusions of Coutchiching mica schist in Algoman granite,
Rainy lake, Ontario.

silicates may be seen from 19 to 20. At 20 the mica
schists clearly dip under the Keewatin. At 21 is a small
exposure of a conglomerate-like rock associated with the
Keewatin.

35069—5

The island at 22 consists of Coutchiching garneti-
ferous schists dipping at 200 to the northwest. By landing
at the north end, an excellent opportunity is afforded to
observe their attitude with respect to the Keewatin group
which underlies the island (23) immediately to the north.

From 24 to 27 are exposures of a hornblende gabbro
showing phenocrysts of basic feldspar. The contacts
of this formation with the Keewatin are not conveniently
exposed on the shores of the lake.

From here, the shore line is followed rather closely
in a northerly direction to 30. Apart from small areas of
Coutchiching at 28 and 29, the exposures consist chiefly
of Keewatin medium-grained, massive to schistose diorite.
At 30 the Coutchiching schists again pass beneath these.

The lake is now crossed in an easterly direction to
31, where a landing is made to examine the excellent con-
tact breccia of Coutchiching and Algoman there exposed.
The inclusions of previously schistose Coutchiching
enclosed in the invading granite, as well as the apophyses
of the latter cutting the former may be noted. A small
area of nearly flat-lying mica schist between 31 and 32
represents a remnant of the roof of the batholith. At
32 a striking exposure showing horizontal jointing in the
granite may be seen from the boats. Just north of 1
another Keewatin-Coutchiching contact might be advan-
tageously examined, after which a return is made to the
station.

ANNOTATED GUIDE (Bear's Pass to Winnipeg).
Miles and From Bear's Pass station the railway runs

Kilometres. , , , . , _., /

along the western edge 01 the Keewatin syn-
clinal trough, described above, to 4, where it
enters the Coutchiching and pursues a course
across the latter nearly at right angles to the
anticlinal axis. The more or less flat-lying
Coutchiching beds in the cuts between mile-
posts 209 and 210, represent remnants of the
batholith roof. After crossing the narrows
northeast of Bear's Passage the railway passes
again into Keewatin, intruded by hornblende
gabbro. Leaving this, another Coutchiching
belt is crossed between mileposts 212-5 (342-
km.) and 214 (344-3 km.), beyond which the

Kilometres Keewatin again outcrops, and with intrusions
lometres. ^ ^ ga^^ro continues to milepost 222. The
gabbro-Coutchiching contact is followed some-
what closely to mile-post 224, where, near
the westerly end of the Rainy Lake crossing,
the railway passes into the Algoman granite.

After leaving the lake, the alluvial plain
country is entered and only occasional outcrops
are visible. The eastern boundary of the bed
of glacial Lake Agassiz (12) has not been very
accurately located, but it is believed to be near
the eastern edge of Rainy lake. The lake
deposits may be seen almost continuously
to Winnipeg, although the sands and stratified
gravels have been rearranged in places to form
part of the alluvial plain of Rainy river.
231-3 m. Fort Frances. — Altitude 113 ft. (340 m.).
372-3 km. The bed-rock from Fort Frances westward to
Winnipeg is almost unexposed. From the
occasional outcrops that do occur, and from
the small mining operations carried on in the
region, it is believed that the country is under-
286 m. lain (Rainy river) chiefly by rocks of Pre-Cam-
460 km. brian age, at least as far west as the Manitoba
boundary The description by Dr. Lawson (6) of
an exposure of possibly Richmond fossiliferous
limestone (Ordovician) about six miles (9-6 km.)
west of Fort Frances is interesting, as it may
prove to be an outlier of the Palaeozoic of
Manitoba.

324 m. Warroad. — At Beaudette the railway crosses
521 -4 km. the International Boundary line into United
States territory, through which it runs for about
35 miles (56 km.), crossing back into Canada
a few miles beyond Warroad.
439 m. Winnipeg. — Altitude 760 ft. (2316 m.).
706 km.

BIBLIOGRAPHY.

1. Coleman, A. P Gold in Ontario; its associated

Rocks and Minerals. 4th. Rep.
Bur. Mines, Ontario, 1894, pp.
35-100.

35069—5i

2 Clastic Huronian Rocks of West-

ern Ontario. Bull. Geol. Soc.
Am., Vol. 9, 1898, pp. 223-238.

3. Iron Ranges of Northwestern On-

tario. Rep. Bur. Mines, On-

4. Mclnnes, W., and tario, 1902, pp. 128-151.

Smith, W. H. C. .The Geology of the Area covered
by the Seine River and Lake
Shebandowan Sheets. Ann.
Rep. Geol. Surv. Can., Vol. 10,
1899, Pt. H., pp. 13-51.

5. Lawson, A. C Report on the Geology of the

Rainy Lake Region. Ann. Rep.
Geol. Surv. Can., 1 887-1 J
Vol. 3, Pt. F., pp. 1-196.

6. The Archaean Rocks of Rainy

Lake Region, Summary Report
Geol. Surv. Branch, Dept. of
Mines, Can., 191 1 .

7. The Geology of Steeprock Lake

Ontario. Memoir No. 1 1, Geol
Surv. Branch, Dept. of Mines
Can., 1911.

8 On Some Post-Glacial Faults near

Banning, Ont. Bull. Seism. Soc
Am., Vol. I.

9. Report of Special Committee on

the Lake Superior Region to
Frank D. Adams, Robert Bell
C. Willard Hayes, and Charles
R. Van Hise, General Commit-
tee on the Relations of the
Canadian and the United States
Geological Surveys, 1904. Jour
Geol., Vol. 13, 1905, pp. 89-104

10. Smyth, H. L The Structural Geology of Steep-

rock Lake, Ontario. Am. Jour
Sci., 3rd Series, Vol. 42, 1891
PP- 3I7-33I-

11. Trueman, J. D Unpublished field notes.

12. Upham, Warren. . . Report of Exploration of the Gla-

cial Lake Agassiz in Manitoba
Ann. Rep. Geol. Surv. Can.
Vol. 4, Pt. E., 1888-89.

13. Van Hise, C. R., and
Leith, C. K

The Pre-Cambrian Geology of
North America. U.S.G.S.,

Bull. 360, 1909.

14.

The Geology of the Lake Superior
Region. U.S.G.S., Mon. 52.,

1911 .

15. Walcott, C. D

Steeprock Lake Fossils. Memoir
No. II, Geol. Surv. Branch,
Dept. of Mines, Can., 191 1.

16. Wood, H. H.

Personal communication.

ORDOVIGIAN AND SILURIAN OF STONY MOUN-
TAIN AND STONEWALL, MANITOBA.

The Teulon-Arborg branch of the Canadian Pacific
Railway runs in a northwesterly direction from the city
of Winnipeg 11 miles (17-7 km.) to Stony Mountain, and
thence continues to Stonewall about 6 miles (9-6 km.)
beyond.

On leaving Winnipeg, Stony Mountain may be seen
rising apparently abruptly from the flat lacustral plain
through which the train passes. The flatness of the coun-
try is emphasized when it is remembered that the "moun-
tain" is 11 miles (17-7 km.) distant and rises only 50 feet
(15-2 m.) above the surrounding country.

Between Winnipeg and the "mountain" no rocks
outcrop and, save for the flatness of the lacustral plain,
there are no features of physiographic or geological impor-
tance. The country is given over to mixed farming, and
the production of dairy supplies for Winnipeg.

A. MacLean.

ORDOVICIAN— STONY MOUNTAIN.

On approaching Stony Mountain, the hill is seen to
the right of the railway. The west and north sides have
abrupt faces, while on the south and east the hill slopes
gradually away to the plain.

The Manitoba penitentiary stands on the brow of
the hill nearest the railway station, while to the north and
east of it are two quarries at present in operation. The
magnesian limestones quarried here are of upper Ordo-
vician age.

These quarries may be easily reached from the spur
which leaves the railway about a mile north of the station
and runs to the front of the quarries. In the quarry
belonging to the city of Winnipeg is a good section which
shows all the strata outcropping elsewhere over the moun-
tain.

Though the beds are apparently flat, they have a
slight dip to the southeast of 2 or 3 degrees. This attitude
is in part responsible for the contour of the "mountain,"
with its sharp face toward the north and west, and gentle
slope to the south and east. Glaciation has, however,
accentuated this by developing a "crag and tail" topog-
raphy by stripping the northern and western fronts and
piling the debris thickly in the lee of the hills to the south
and east.

On the top of the mountain glacial material is very
scant, varying from a few inches to a few feet in depth.
This rests on the upper limestone of the quarries, which,
in most cases, shows scored and striated surfaces when
freshly stripped. Below this a buff magnesian limestone
is quarried for a depth of 12 or 14 feet (3-6 to 4-2 m.),
when beds of yellowish brick-like shale are reached. These
beds are 14 feet (4-2 m.) in thickness and rest on a reddish
shale interlaminated with thin layers of limestone. The
various beds exposed in the vicinity of the mountain com-
prise the "Stony Mountain" formation (3) which is com-
posed of three main divisions: (A) an upper magnesian
member about 12 feet thick in which the quarries are loca-
ted and which contains a very meager fauna including se-
veral Beatriceas from the size of a cigar up to four inches
in diameter and a foot in length, together with brachio-
pods and occasional corals; (B) a middle member about
15 feet thick consisting for the most part of a massive yel-
low brick-like shale which is almost filled in places with
the casts and moulds of corals, bryozoans, brachiopods,

pelecypods, gastropods, cephalopods, and trilobites, a sco-
re or more of species having been identified; and (G) an
exposed thickness of 12 feet of alternating thin limestone
bands and red shale, the limestone layers bearing upon their
weathered surface an even greater assemblage of fossils
than were mentioned for the middle member, over fifty
species having been identified, as follows: 5 corals, I cri-
noid, 17 bryozoans, 8 brachiopods, 8 gastropods, 3 cepha-
lopods, 9 ostracods, and 3 trilobites. The interlaminated
shale crumbles readily and specimens of corals, brachio-
pods, and bryozoans can be picked up from its weathered
slopes. The detailed section of the beds in descending
order is as follows :

Mantle rock. — Glacial till, consis-
ting of sand, gravel, and boulders,
local and "foreign", with some
clay and surface layer of soil. 2 inches to 5 feet,

5 to 15-2 cm.

1. Limestone. — Hard, white in co-
lour, showing few or no fossils.
In some places this has been strip
ped from the top of the quarry . . 24 inches, 61 cm.

2. Limestone. — Hard, white in co-
lour, breaks into 5 or 6 layers
of irregular thickness. Surface
may weather porous. Fossils
not evident 14*5 inches, 37 cm.

3. Limestone. — Rusty, yellow, joint
faces. No fossils 32 inches, 81 cm.

4. Limestone. — Compact, yellow,
often shows coarse porous struc-
ture 40 inches, 102 cm.

*5. Limestone. — Yellow, with po-
rous bands near top and bottom. 59 inches, 150 cm.

* Beds 2 to 5 constitute the quarries as they are usually worked. Fossils are not
entirely absent, but the perfection with which the fossil is merged in the rock and the
uniformity of both in texture and composition renders it difficult to detect them.
In rare cases they are exposed by weathering in the quarries, the most striking
of these fossils being the Beatriceas, which attain a diameter of four inches and a len-
gth of a foot or more.

6. Arenaceous shale. — Brick-like
in texture, varies in colour from
yellow to purple. Carries fossils
of gastropods, brachiopods, co-
rals, etc

10 inches, 25 cm.

7. Calcareous shale. — Yellow,
brick-like, showing in some loca-
lities fossils, generally as casts
or moulds (

60 inches, 1 52 cm.

8. Calcareous shale. — An irregular
bed, weathering readily to a no-
dular mass, although in some
places more compact. Few fos-
sils •

36 inches, 91 cm.

9. Calcareous shale. — Yellow, brick-
like, very much like No. 7. Con-
tains fossils, corals, bryozoans,
brachiopods, gastropods, etc.,.. .66 inches,^i68 cm,

10 Shale. — Red, loose in texture,
weathering readily to a crumbling
mass. Interlaminated with lime-
stone beds about 2 inches in

The beds exposed in this section are believed to repre-
sent the Richmond and possibly the Lorraine formations
of the Ohio Valley. Good sections of the lowest shale
of the above section can be obtained in abundance.

This lowest shale is the best of the series for the
collection of fossils, and is exposed at several places over
the mountain. One of these is to the south of the Winnipeg
city quarry, and just below the Manitoba quarry, near
their old lime kiln. Two other exposures are on the
prison reserve: one in the prison gravel pits in the face
of the hill opposite the main buildings; the other a short
distance to the southeast of this and in the same face of the
same hill.

thickness. Both limestone and
shale are quite fossiliferous, bea-
ring corals, bryozoa, brachio-
pods, gastropods, cephalopods,
ostracods, and trilobites

144 inches, 366 cm.

7:^

The shale above this (Nos. 7, 8, and 9 of the above
section) is best exposed for collecting purposes in the cut
on the east and west road to the north of the prison reserve,
where 16 feet (4 -8m.) of thin bedded shaly limestone are
exposed. Fossils occur here abundantly and include
Favosites aspera, Cyathophyllum sp., Platystrophia bifo-
rata var. lynx, and Rhynchotrema capax. An occasional
massive specimen of Favosites aspera may be seen in the
basal beds of the quarry immediately north of the village.
These sometimes have a diameter of 12 to 15 inches
(30 to 38 cm.).

As already mentioned the beds which are quarried,
yield but few fossils. Such as do occur may be best seen
in some of the abandoned quarries, where weathering has
assisted in bringing out an occasional one. Such a quarry
is to be found directly east of the Manitoba Company's
quarry, to the south of the road allowance which passes
between the two quarries.

Beneath the light covering of till, the surface of thin
limestone has been beautifully polished and striated in a
direction S 200 E, furnishing evidence of the latest advance
of the Keewatin glacier from the north and northwest.
The Labradorian glacier from the northeast also reached
this hill at a later period, but the striae left by it, being
about southwest, are not abundant, as the older till pro-
tected the underlying rock. On the brow of the eastern
side of the mountain, however, is a little ridge six feet
(1 -8 m.) high of angular blocks of limestone which may be
a morainal accumulation shoved up by this glacier.

On the opposite side of the hill is an old gravel beach
of Lake Agassiz, and in the head of the horseshoe-shaped
summit is another lower beach.

SILURIAN— STONEWALL.

Between Stony Mountain and Stcnewall there are
no rock exposures along the line of railway. The country
continues quite flat, but between the two stations there
is a rise of about 50 feet (16-7 m.), Stony Mountain being
777 feet (235 m.) above sea level, and Stonewall being
826 feet (251 • 7 m.).

Just before entering Stonewall a test pit may be seen
on the south side of the railway. On the north side,
spurs lead to the quarries of the Manitoba Quarry Com-
pany.

Passing through the station, the track takes a semi-
circular course about the west side of the town, and turns
in an easterly direction along the north side of the quarry
operated by the Winnipeg Supply Company. In this
quarry, the deepest cutting has been made and the best
section is to be seen.

The strata are only exposed in the quarries, being
elsewhere covered to a depth of 2 to 12 feet (.6 to 3.6 m.)
Below this the surface of the rock is generally deeply
scored, but in most cases the glacial polish has been removed,
in all probability by the solvent action of surface waters.
The rock is generally quarried to a depth of 12 or 14 feet
(3.6 or 4.2 m.) below the topmost bed. When quarried
it is used for crushed stone, rubble, and also for lime, for
which it is eminently suited. The floor of the quarry
is of red shale some 15 inches (38 cm.) in thickness, below
which is six feet (1.8 m) of limestone in two beds. This
is very hard, darker in colour than the limestone above,
and is unsuitable for lime. Below this is a dark red shale
which continues in depth below the level now exposed.

The section in descending order is as follows : —

Soil and non-assorted material.
Boulder clay or till of variable
depth.

Stratified material. Alternate

layers of sand and shale, one
inch to one quarter inch in thick-
ness. Shale is well assorted.
Sand layers are poorly assorted.
No fossils 16 inches, 41 cm.

Boulder clay or till, lying on surface
of rock which is scored and stri-
ated 33 " 84 cm.

Limestone, light colored and mag-
nesian representing the upper-
most course of quarry which in
many cases has been removed.. .60 inches 152 cm.

Limestone of the second course.
Hard, massive, and very similar
to the overlying bed from which
it is distinguished only by differ-
ence in thickness. Both these
B. <i courses contain a tabulate coral,
generally poorly preserved except
in one locality, to which refer-
ence will be made later 41 104 cm.

Limestone. This is the lowest cour-
se generally quarried. Less mas-
sive than either of above, quite
often breaking into laminae 2 to
10 inches (5 to 25cm.) in thick-
ness 48 " 122 cm.

In one portion of this quarry operations were at one
time continued below this, revealing the following: —

Shale, red and nodular in char-
acter. The individual nodules
are fairly hard, but the mass
does not form a consistent bed . . 15 inches, 38 cm.

Limestone, yellowish in colour,
hard and porous, probably mag-
nesian. The pores are large,
resulting probably from weather-
ing out of fossils or other more
soluble content. Tabulate cor-
als and cephalopod remains occur
in this layer 31 " 79 cm.

Limestone, similar to above, but
lower half is darker in colour, and
has much finer pores, uniformly
distributed. Forms the "free-
stone" of this level 41 " 104 cm.

A test pit sunk at one corner of this part of the quarry
shows other layers below this as follows: —

Clay-like shale, fine grained, white

in colour 6 inches, 15 cm.

Bright red shale, breaking by
irregular fracture to a mass of
small angular particles. This
bed is here exposed for 36 inches
(91 cm.), and is reported to have
a total thickness of 6 feet, 183 cm

Below this is said to lie seven feet (201 cm.) of freestone,
but whether this is a hard porous dolomitic limestone
or a true sandstone could not be determined. It is probably
the former.

The strata at this place contain few fossils. The
beds below those indicated "A" to "C are exposed only
in this quarry and contain few fossils. The fossils from
the upper limestone occur in more abundance in an old
quarry of the Manitoba Quarry Company, a little to the
south and east of this one. In this place they occur quite
freely in the walls, and in the rubble scattered over the
floor of the quarry. Although the spicies are few,
the specimens occur in large numbers and are well preserved.
This quarry is reached by going east on Higgins street
or Drake street, or by entering from the railway spur,
previously mentioned, from the main line to the east
of the station.

The most common species occurring here are Favosites
as per a, F. gothlandicus , and Plectambonites? , sp. undet.
Other species occurring here include A phyllo stylus gracilis,
Trimerella sp. undet., Dinobolus cf. conradi, and several
species of gastropods and cephalopods. The new cephalo-
pod, Sphyroceras meridionale Whiteaves and Cyrtoceras
cuneatum Whiteaves. and a new genus of corals Aphyl-
lostylus have been described from material collected in the
Stonewall quarries. (4).

The fauna is of Silurian age and is probably the equi-
valent of either the Guelph or Lockport. It represents a
faunal province distinct from that of Ontario and Western
New York, which makes precise corralation with the New
York section impracticable.

The beds in the quarry walls appear horizontal, but
those in the floor of the quarry show a distinct dip. In one
case this is 2 or 3 degrees in a direction almost due south ;
in another case, one quarter mile distant, the dip is 2 or
3 degrees in a direction due west. The general dip over
all the quarries is toward the southwest.

Grooves and striae trending S 200 E, made by the
Keewatin glacier, may be seen on all fresh surfaces, while
here and there some striae of the Labradorian glacier
may be detected running N 8o° W.

The presence of the stratified and partially assorted
layer between the two boulder clays is indicative of a
temporary recession of the ice, although the thinness
of the layer and the absence of organic remains would
suggest that it was probably local and of short duration.

BIBLIOGRAPHY.

1. Ulrich, E. O G.S.C. Contribution to Canadian

Micropaleontology, Pt. II, 1889,
PP- 27-57-

2. Whiteaves, J. F G.S.C. Paleozoic Fossils, Vol. Ill,

Part II, 1895, pp. m-128.

3. Dowling, D. B G.S.C, Vol. XI, Part F., 1898, p. 46.

4. Whiteaves, J. F G.S.C. Paleozoic Fossils, Vol. Ill,

Part IV, 1906, pp. 278-283.

WINNIPEG TO BANKHEAD.

D. B. Dowling.
INTRODUCTION.

THE GREAT PLAINS.

The central part of the continent to the east of the
Rocky Mountains is generally referred to as the Great
Plains. This name, as applied to the southern portion
of the region, is descriptive mainly of its treeless character.

It is however not without variety in its topography since
a large part of it is a northeasterly sloping plateau of
Mesozoic sediments etched into somewhat irregular surface
contour, and overlapping a lower plain having the irregular
features of the great pre-Cambrian shield.

In the belt traversed by the railway lines, a threefold
division of prairie steppes rising one above the other to
the west is clearly recognizable, though the term prairie
may not be applicable farther north. These three divi-
sions are here adopted for descriptive purposes and a
fourth is added to include the broken, hilly country of the
foothills.

The first and eastern division comprises the plain east
of the Cretaceous deposits which rise as a low escarpment
to form the plateau. The second extends from the edge
of this plateau westward to the erosion remnants of former
Tertiary deposits and the third from this line westward
to the foothills.

First Division. — This division is the lowest in elevation
and is essentially a region of lakes, with the exception that
in the southern part the inequalities of the rock surface
have been smoothed over by the deposition of clays and
silts in glacial Lake Agassiz. This forms the rich farming
country of southeastern Manitoba, where the extreme
evenness of surface is noticeable because of the general
absence of timber. This plain is however being partly
forested by the individual efforts of the farmers.

The surface features east and north of Lake Winnipeg
differ from those to the west in having the mammillated
character typical of a region underlain by Pre-Cambrian
rocks with but a thin mantle of drift. The large lake
basins are due mainly to the removal of Palaeozoic rocks
from the older westerly dipping rock surface.

Traces of the margin of glacial Lake Agassiz remain
in distinctly marked beaches resting on the slopes which
rise upward to the Cretaceous plateau.

The railway ascends to the Cretaceous plateau up
the wide delta and valley of the ancient Assiniboine river,
where it entered Lake Agassiz. The present drainage of
this region is northward to Hudson bay by Nelson river.

Second Division. — This division is the lower or eastern
portion of the plateau and is underlain by a succession of
shale beds and other equally soft rocks. The surface is
about 1,000 feet (304 m.) above the Manitoba lakes or

1,800 feet (545 m.) above sea level, but is not a ^orm
I tain. Several deep valleys traverse it, one of which was
incised by the water of the South Saskatchewan river at
a time when the northward flow of that stream was blocked
bv elacial ice. This channel is now occupied by a small
stream called Qu'Appelle river. Streams flowing eastward
acrosTthe plateau have cut deep valleys into the escarp-
ment which rises from the lower prairie level to the east
and have left remnants standing as isolated hills which
are known as the Pembina, Riding, Duck, and Porcupine
m0UThendra inage ^ eastward into a conflUent series of
streams entering the Assiniboine valley and northeastward
into the Saskatchewan. Wooded areas occur in the north
and along the outer edge of the plateau, while a few of
the higher levels of the central surface are similarly covered.

Third Division.-This area, extending from the
Coteau, or the hilly country just west of Moosejaw. to
the foothills of the Rockies, is divided by the depression
through which the South Saskatchewan river flows lo
the north of this depression the drainage is mainly eastward
to the North Saskatchewan, while the region to the south
„Xles a fringe of the drainage basin of the Missouri
river There is also immediately west of the Loteau a
small basin without outlet whose waters evaporate in
Lakes Johnston and Chaplin.

The relief in this division is accentuated by the tact
that much of it is bare of trees, so that such elevations as
the flat topped Cypress Hills standing 2,00 c .feet (608 m)
above the railway near Medicine Hat or the Hand Hdls
800 feet (243 m.) above the surrounding plains, become
prominent topographical features. 1
Fourth Division .-The topographic character of the
foothills is much more diverse than that of the other
Sons. The geological structure is closely related to
"he tocography, and 111 the hills are formed of folded or
faulted rock masses.

Since the folding in these hills is due to the same
causes that produced the Rocky mountains, the strike ot
Z folds follow directions nearly paralle to the mountain
chain Although often of considerable elevation the
summits of thefoothills are not as serrated as the moun-
tains, since the rocks composing them are of softer ^mater-
ials. Their flanks also are either grassed or clothed with

35069—6

timber. The general arrangement is a belt of varying
width and elevation consisting of parallel ridges cut here
and there by streams rising in the mountains behind.

ROCKY MOUNTAINS.

On the basis both of form and of structure the Rocky
Mountain system is divisible into two parts: — a western,
and an eastern part. The axial ranges constituting the
western part have been carved from a slightly folded
but greatly elevated block, the denudation of which was
probably inaugurated before the eastern ranges were
elevated. The eastern part is made up of monoclinal
blocks, the beds of which they are composed being gener-
ally younger in age than those of the western part of the
mountains.

Outer Ranges. — As topographic features these ranges
are in a general way merely blocks more elevated than
those of the foothills, from which nearly all the younger
soft series of rocks have been removed, exposing the more
consolidated Palaeozoic sediments beneath. The fault
blocks are, as a rule, tilted westward, and along their
eastern scarped faces remnants are often found of the
anticlines which were broken near the crest, showing that
these blocks were the western limbs of folds overturned
and broken. The plane of the overthrust faults is fre-
quently inclined at a comparatively low angle indicating
that the thrust was from the west. The outer fault is
often of this character, and the overthrust, although
great in Montana, becomes modified in the Canadian
ranges and decreases northward. In southern Alberta the
Palaeozoic rocks of the watershed range on the British Col-
umbia boundary line overlap the Cretaceous beds of
the western part of the fault block, forming the Livingstone
range ; and Crowsnest mountain, which is an erosion remnant
of Palaeozoic superposed upon Cretaceous rocks, stands as
an example of this overthrust. The westward slopes of
of these fault blocks depend to a great extent on the dip
of the beds, so that a similarity in outline of their slopes
is repeated along the range. The eastern slopes are often
more abrupt, and their form depends largely on resistance
of the strata to erosion or a disposition of fractures. Local
glaciers have, moreover, etched this face into cirques and
thereby contributed to the irregularity of the crest line.

The Western Rocky Mountains. — In contrast to the
outer or eastern ranges, the mountains near the watershed
stand in isolated peaks, carved from a large block of older
rocks. Less folding and fewer faults occur. More massive
bases and higher summits, to which cling many glaciers,
give a more Alpine aspect to the scenery. Small cirques,
such as the gap called White Man's pass at Canmore,
in the outer mountains, give place in the inner ranges
to great amphitheatres such as those in the vicinity of
Laggan.

The first appearance of this part of the Rocky Moun-
tain system may have occurred shortly after the Jurassic
sediments were laid down, and then only as low ranges.
Periods of subsidence and elevation may have followed
and recurred throughout Cretaceous times.

HISTORICAL GEOLOGY.

The wide depression, in which the sediments of the
central part of the continent were deposited, was at its
greatest marginal extent probably in Devonian time.
Earlier deposits appear on the southeastern margin and
again in the mountains to the west.

A great series of ancient sediments, some probably
Pre-Cambrian in age, is found in the area occupied by the
western part of the Rocky mountains and the adjoining
ranges to the west. This thick series shows in its upper
part the existence of marine conditions during Cambrian
time. The downwarp, which was here partly filled by
coarse sediments, may not have extended far to the east
from the continental margin of that time, and was probably
separated from the main ocean by a barrier. A general
subsidence before the close of the Cambrian is indicated
by patches of rocks of this age on other parts of the con-
tinental area. Deep sea deposits, magnesian limestones
of the Castle Mountain series, were formed before the
recovery of elevation which closed the period.

Considering only the area east of the Rocky mountains,
it is not clear, that during Ordovician time, the marine
invasion shown by the character of the sediments at the
top of the Castle Mountain series was other than by an
arm of the Pacific. In the eastern part the invasion from
the south in early Trenton time is marked by the deposition

35069— 6J

of limestones in the Lake Winnipeg basin. A more
general submergence during Devonian time is represented
by beds of magnesian limestone which are exposed along
the foot of the Cretaceous escarpment across Manitoba
and in a broad sheet northward down the Mackenzie
river and in the Rocky mountains throughout their entire
length. The absence of the succeeding Carboniferous
deposits in the eastern part of this basin, as well as to the
north, suggests a retreat of the sea westward. In the
mountain region Carboniferous limestones are prominent
in southern Alberta, but northward these thin out and
are replaced by sandstones and shales.

A farther retreat during Permian and Triassic time,
during which sandy and shaly deposits were laid down,
is indicated in a thin series of these rocks in the mountains.
They extend northward to Stewart river in the Yukon,
and prove that with the shallowing of the Carboniferous
sea there was also transgression northward.

The crustal disturbances of Jurassic time in British
Columbia were reflected in the inauguration of another
downwarping movement that produced a narrow trough
in the belt now occupied by the Rocky mountains. This
permitted the entrance of the sea from the north across
northern British Columbia. The deposits carried to this
basin in general went to form fine grained black shales.
Sandstone members appear in the lower part at intervals,
but generally the source of the material is believed to
have been at some distance. In northern British Columbia
volcanic ash is intercalated with the sediments, and vol-
canic outflows are found on what were probably land
areas.

At the close of the Jurassic, sedimentation became
periodically rapid. Sands were washed into the basin
and the surface elevation was maintained at or near sea
level, so that the continental drainage replaced the saline
water in the basin. Land areas were maintained for
long periods during which coal seams were formed from
the vegetation. This period, which is generally ascribed
to the Lower Cretaceous, was closed by a general subsid-
ence to the east, in which the sea advanced again to cover
a large part of the centre of the continent. This invasion
of the sea submerged the fresh water deposits of the Dakota
in the east and also spread in the central part of the basin
similiar sandy beds as basal members of the marine series.

In the west the marginal beds below the marine Cretaceous
sediments are as a rule fresh water deposits. The coarse
conglomerates and sandstones, there found belonging
to this period of extension of the Cretaceous sea, indicate
some corresponding uplift in the land area to the west
which increased the gradient of the slopes. The coarse-
ness and thickness of the material contained in these
beds (maximum 6000 feet, 1824 m. in Crowsnest area,
reduced rapidly to the east to less than 900 feet (274 m),
suggest a nearer approach to the zone in which mountain
building was active, probably in the southern part of the
present western Rocky mountains.

Throughout the later stages of the Cretaceous, the
eastern part of the basin shows little change in the
deposits which were mainly marine clays. The western
part, as exposed in the deposits of the faulted zone, shows
repeated subsidences and elevations up to sea level. Active
denudation of the western land areas is shown in conglomer-
ates at the top of Benton shales exposed on Bow river and
northward on the Brazeau and Athabaska rivers. Con-
glomerates also occur in the Belly River series at Crows-
nest mountain and in the north in the Brazeau fields.
This material was probably eroded from the hills appear-
ing to the west, the prototypes of the western portion
of the Rocky mountains.

The periods of elevation along the western margin
of the interior region with the consequent changes in
deposition, while not always prolonged, appear at one
stage to have been of sufficient magnitude to allow the
accumulation of a large body of brackish water deposits,
the Belly River series. The surface so exposed was at
times covered by vegetation, and thin coal seams were
formed. This was subsequently covered by the marine
deposits of the Pierre stage of Cretaceous time.

The close of the Cretaceous marine invasion is marked
by the brackish water beds containing the coal seams of the
Edmonton formation. During Tertiary time the deposits
were distributed in fresh water and this part of the contin-
ent was raised to sea level — the distribution bringing in land-
locked lakes or confined estuaries. The western Rocky
Mountain ridges probably did not bar drainage from the
gold bearing rocks of British Columbia, since the source
of the gold in northen Alberta streams is credited to the
lowest Tertiary or beds at the top of the Cretaceous.

The exact date at which elevation of the Rocky Moun-
tains commenced is not certain, but it is probable that from
early Cretaceous times the crust here was under strain
and that at intervals during the warping of the crust
before the close of that period the western part of the range
had been marked out by hills which were being denuded of
their top covering of shales, quartzites, and limestones
to swell the accumulations in the Cretaceous sea to the
east. The period of mountain building to which the
elevation of the Rocky Mountains is assigned, the Laramide
revolution, is probably a long one. The formation
of the outer ranges with their frequent great overthrusts
eastward, was subsequent to the elevation of the ranges
of the watershed or to the deposition of the early Tertiary
beds of the Paskapoo formation.

The denudation of post-Tertiar . times has removed
most of the broken material resulting from this late revol-
ution, but the large well rounded pebbles in the Oligocene
beds of the Cypress and Hand Hills, are probably the
remains of that material. This period of mountain
building is probably later than the Laramie and occurred
between the Paskapoo or early Tertiary and the Oligocene.

Part of the denudation of the early Tertiary and
Cretaceous beds of this basin may have been accomplished
at this time, especially in the part near the mountains,
but the greater part was due to a general elevation in
Pliocene times, when much of the area was in process of
reduction. The amount of material removed is well
shown on the north side of Cypress Hills, where from the
level of the Oligocene deposits the Saskatchewan river
is now cutting through horizontal beds that are 2,000
feet (608 m.) below. The wasting away of material from
the edge of the basin was also continued and before Glacial
time the plateau of Cretaceous deposits assumed nearly
its present form.

Many of the present valleys are broad depressions
formed in pre-Glacial time, and sometimes show old stream
gravels, derived from the Oligocene conglomerates, covered
by the boulder till. Glacial deposits are spread over all
the area, and, almost to the mountains, hold erratics
derived from a northeastern source. The Cordilleran
glacial material has been carried but a short distance
eastward from the mountains.

The question of the extension of the continental ice
sheet is still an open one and the glacial till west of the
Coteau is believed by many to have been carried by
floating ice. The closing stage of glaciation was no doubt
one in which the ice front held back large lake-like basins,
of which the best known is glacial Lake Agassiz which
occupied the basin at the eastern edge of the Cretaceous
plateau. This lake at first drained southward to the
Mississippi valley, and at that stage formed many beaches
along its western and southern margin. These beaches
show a gradual rise to the north due to an upwarp
of the crust, which caused the waters to continue
their discharge southward until on the retreat of the
ice to the north an outlet was found in that direction.
Many of the former drainage channels were ice blocked,
and the lake received a large inflow from the southern
part of the plateau to the west of it. As a result of the
valley cutting which ensued at this time, a great burden
of fine-grained material was deposited in this basin to
form the lacustrine deposits of the Manitoba plains.

SUMMARY DESCRIPTION OF FORMATIONS.

ORDOVICIAN.

In Manitoba the Ordovician includes the following
formations : —

Stony Mountain formation, consisting
of yellowish and reddish lime-
stones overlying dark shales.

Exposed at Stony Mountain no feet (33-5 m.)

Upper mottled Limestone 150 " (45*7 m.)

Cat Head limestone 70 " (21 m.)

Lower mottled limestone 70 " (21 m.)

The divisions of the Trenton here indicated are made
on physical grounds. The exposures are best seen on
Lake Winnipeg. No deposits of this age occur in the outer
ranges of the Rocky mountains.

SILURIAN.

The Silurian is composed of light-coloured, thin-
bedded, yellow limestones. In the region to the east of
Lake Manitoba important beds of gypsum are being mined
from this formation.

DEVONIAN.

In Manitoba the Devonian rocks are divisible into
three series as below: —

Upper Devonian or Manitoban, consisting
of light gray, hard brittle limestone,
with red argillites at the base,
about 200 feet (64 m.)

Middle Devonian or Winnipegosan, con-
sisting of light yellow, hard dolo-
mite, with porous beds beneath,
about 200 feet (64 m.)

Lower Devonian, mainly red shales.
These beds probably represent only
the upper part of the lower Devonian
of eastern America, about 100 feet (30 m.)

In western Saskatchewan these beds may be found
near the Churchill river; having nearly the same characters.

In Alberta, the most eastern exposure is in the neigh-
borhood of Athabaska river. In the Rocky mountains
they form the Intermediate series, brownish, irregularly
hardened dolomites, and greyish, crystalline dolomites,
with some sandstones and quartzites.

CARBONIFEROUS.

These rocks are found in South Dakota, Montana,
and Alberta. They are not exposed in Manitoba or along
the northwest margin of the Cretaceous plateau, but are
confined to the Rocky Mountain region. They have been
subdivided on lithological grounds into upper and lower
Banff limestones. These formations are each capped by
shaly beds, from which have been obtained a few charac-
teristic fossils. The formation is generally a bluish
limestone, and forms the summits of Cascade and Rundle

mountains, near Banff. A thickness of over 6,000 feet
(1,824 m.) for the formation has been observed in the
Bow valley.

PERMIAN AND TRIASSIC.

At the top of the limestone series in the Rocky moun-
tains, a series of quartzites overlaid by red shales may
be in part Carboniferous, but as the series is conformable
to the Jurassic, some deposition should be credited to Per-
mian and Triassic. The red shales are occasionally capped
by a thin band of yellowish dolomite, and often the series,
on fresh exposures, shows yellow bands in the shales.
Evidences of a Triassic age for the upper shales have been
found in shells of Monotis type. These are recorded at
Blairmore in the south and on branches of Brazeau river.
Northward Triassic fossils have been found in Pine and
Peace river valleys.

JURASSIC.

Fernie shale — In the locality where this formation
received its name, Fernie, B.C., it consists of a series of
black and brownish shales 1,060 feet (323 m.) in thickness
overlying 500 feet (152 m.) of sandy argililtes. Eastward
the series decreases in thickness. On the Cascade river
the section is 1,600 feet (487 m.) and consists of black
shales and grey sandstones with an occasional limestone
bed toward the base. In the Moose Mountain area — an
outlier of the Rocky mountains — the thickness is about
225 feet (68 -5 m.). The formation has been traced
northward to Athabaska river and preserves its general
black, shaly appearance. Few fossils have been obtained
in these measures, but they are characteristic : — Cardioceras
canadense, Peltoceras occidentale, Terebratula robusta, Ostrea
skidegatensis, Exogyra sp., Lima perobliqua, Pteria corneui-
liana, Trigonoarca tumida, Trigonia dawsoni, Astarte car-
lottensis, Protocardia hillana, Cyprina occidentalism Pleuro-
tonomya carlottensis, Schlcenbachia borealis , S. gracilis.

CRETACEOUS.

Kootenay. — The lower member of this series of depo-
sits is found resting upon the Jurassic in the Rocky moun-
tains. In Manitoba it has not been recognized, and is

supposed to have formed but a very thin sheet east of the
mountains. The base of the formation is a heavy bed of
sandstone, which is succeeded by sandstones and shales
containing many coal seams. A bed of conglomerate
divides the formation in its northward extension, and few
coal seams are found in the lower part. In the south
the thicker seams are in the lower part. The greatest
thickness occurs in the mountains and on Elk river in east-
ern British Columbia. Near Banff in Alberta the thickness
is about 3,700 feet (1,127 m-)- In the Bighorn basin this
thickness continues. Eastward at Moose mountain it
is only some 375 feet (114 m.). The fossils of the forma-
tion are plants, such as ferns, cycads, and conifers.

Dakota. — In the mountains above the coal bearing
formation, occurs a series of conglomerates and sandstones
that is not distinctly coal bearing, although thin coal
streaks occur in it. Fresh water conditions prevailed
in the mountain section and on the eastern margin during
this period of deposition. In the lower part of Athabaska
valley, the upper beds at least contain marine fossils.

The thickness of the formation in Manitoba cannot
be much more than 200 feet (61 m.). In the foothills
a thickness of 950 feet (290 m.) seems to represent the
whole formation; but, westward in the Elk river escarp-
ment, a shore deposit thousands of feet in thickness occurs
at this horizon.

Benton. — Dark grey, almost black, shale of marine
origin, forms a continuous sheet probably across the
whole interior basin. In Manitoba the deposit is about
175 feet (53 m.) in thickness. In the foothills it is over
700 feet (213 m.), but this undoubtedly includes part
of the overlying Niobrara. The entombed forms of animal
life include Inoceramus problematicus, Scaphites ventricosus
and Prionscyclus woolgari.

Niobrara. — In Manitoba, this formation consists of
grey calcareous shales, which are an upward continuation
of the Benton. Westward it is not so characterized in
the marginal deposits there, since a period of unrest in the
mountains occurred about that time accompanied by brief
retreats of the shore line due to a slight rising of the crust.
The formation is from 130 to 200 feet (40 to 61 m.) thick
in the eastern part. The presence of foraminifera is
a characteristic feature of the formation. The fossils
include Serpula semicoalita, Ostrea conjesta, Anomia obliqua,

Inoceramus problematicus, Belemnitella manitobensis, Lori-
cula canadensis, Ptychodus parvulus, Lamna manitobensis,
Enchodus shumardi, and Cladocyclus occidentalis.

Pierre. — Marine deposits with little trace of calcareous
matter succeed the Niobrara. In places almost 1,000 feet
(304 m.) of shales are found in the formation. It is claimed
that in the western part a great uplift occurred during the
early part of this time interval, and brackish and fresh
water deposits were formed and afterwards covered by
marine beds before the close of the period. In Manitoba
the marine sediments are divided into an upper or Odanah
and a lower or Millwood. The time interval between the
two may coincide with the period of uplift in the west.
The western section is divided into Bearpaw shales, Belly
River series and Claggett shales.

Claggett. — The " lower dark shales" of Dawson in
southern Alberta have been given a thickness of 800 feet
(243 m.). In Moose Mountain 250 feet (76 m.) of shale
is supposed to represent this division. They are marine in
origin and hold fossils of Pierre type.

Belly River. — This series of shales and sandstone beds
are light-coloured and in appearance very much like the
beds at the top of the Cretaceous. The fossils are brackish
water types with probably fresh water forms in the upper
part. Land conditions prevailed toward the close of this
period of deposition and coal seams were formed. The
measures extend eastward from the vicinity of the moun-
tains into Saskatchewan. The thickness of the formation
is about 800 or 900 feet (243 or 274 m.), but probably
thins eastward. A similar series on the Peace river — the
Dunvegan sandstones — probably belongs to this period.

Bearpaw. — The Pierre-Foxhill of Alberta and Sas-
katchewan is without doubt the equivalent of the Bearpaw
of Montana. The formation in Alberta is about 700 feet
(213 m.) in thickness. The fossils are marine and comprise
among the common forms, Baculites compressus, B. grandis,
Scaphites nodosus, Placenticeras placenta, Inoceramus altus,
I. nebrascensis, I. tenuilineatus , and many others.

Edmonton. — In southern Saskatchewan the beds for-
merly called Laramie are divisible into a lower brackish
water series and an upper fresh water one. The lower
bears the same relation to the upper that the Edmonton
does to the early Tertiary.

In southern Alberta the formations above the marine Cre-
taceous are divided in three subdivisions, the lowest of which
at least forms part of the Edmonton division of northern
Alberta. This is the brackish water portion of the forma-
tion, so called Laramie, and is generally placed at the top
of the Cretaceous. The upper limit, the top of the coal
horizon, may in time be considered Tertiary. The fossils
consist of Dinosaurian remains, with land plants, and the
following brackish water animal remains: Ostrea glabra,
Unio danae, Corbicula occidentalism Panopce simnlatrix and
P. curta. The thickness of the formation varies but attains
a maximum of 700 feet (213 m.) in central Alberta.

TERTIARY.

Paskapoo. — This series consists of fresh water deposits
generally of yellowish sandstones and bluish grey and
olive sandy shales. It embraces the upper part of the
Laramie of southern Alberta and Saskatchewan, with
a total thickness in western Alberta of 5,700 feet (1737m.).
The remains of plants are numerous in it and denote a
flora of a temperate climate. Fresh water fossils include:
Unio dance, Sphaerium formosnm, Limncea tenuicostata,
Physa copei, Acroloxus radiatulus, Thaumastns limncei-
formis, Goniobasis tenuicarinata, Campeloma product us,
Viviparus leai, Valvata filosa, and V. bicincta.

Oligocene. — Isolated exposures of coarse grained
material, deposited on the Paskapoo representative of
the Tertiary in Saskatchewan, have been found to contain
a considerable number of Mammalian bones. These
beds are characterized by a great quantity of waterworn
pebbles derived from the quartzites of the Rocky mountains.

ANNOTATED GUIDE.

Miles and
Kilometres.

o m. Winnipeg — Altitude 760 ft. (231 m.). The

o km. capital of Manitoba, population 130,000. The
character of the country passed through east
of this city shows a gradual change from the
hilly surface of the Pre-Cambrian shield to
an apparently level plain. This is the lake
bottom of a former lake of Glacial time called

K?ioSeatres Lake Agassiz. The sediments at the south
end of this basin were brought in very rapidly
by a strong system of drainage across the Cret-
aceous plateau to the west, and the erosion
of the soft rocks of that region provided abun-
dant material for filling inequalities in the rock
surface forming the bed of the lake. At its
highest stage Lake Agassiz extended southward
to Lake Traverse in Minnesota and drained
to the Mississippi valley. At Winnipeg, the
depth of water was about 560 feet (170 m).
Beaches along the western margin were formed
at several stages of the lake recession and these
show an upwarping of the crust. A vertical
projection of the beaches accompanying this
description shows graphically the amount of
this movement. The subsidence of the lake,
with the retreat of the ice barrier to the north-
east, did not at once alter the direction of
drainage, and the southward flow wTas main-
tained for several stages owing to the upwarp
to the north. An outlet northward was found
while the water was 240 feet (73 m) deep
over the position now occupied by the city
of Winnipeg.

In going westward from Winnipeg the rise
is very slight across the lower part of the old
lake basin, and, since the railway ascends
to the rim of the basin on the delta of the prin-
cipal stream tributary to the lake, beaches
are not strongly in evidence. These are how-
ever strongly marked both to the north and
south and are indicated in the accompanying
illustration.

55 m. Portage la Prairie — Altitude 851 ft. (259 m).

88 km.

62 m. Burnside — Altitude 869 ft. (265 m.).

100 km. Shortly after passing Portage la Prairie the
railway crosses a succession of beaches of the
ancient glacial Lake Agassiz: the Burnside
beach four miles west of Portage la Prairie,
and the Gladstone beach two miles (3.2 km.)
beyond Burnside near Rat creek.
70 m. Bagot — Altitude 936 ft. (285 m.).

112 km.

Miles and
Kilometres.

77 m. MacGregor — Altitude 956 ft. (291 m.). At
124 km. the 69th mile post, or about two miles (3 . 2 km.)

west of Bagot, is the Emerado beach, and one
mile (1.6 km) west of MacGregor the lowest
of the Blanchard beaches is crossed.
84 m. Austin — Altitude 1,015 ft. (309 m.). When
135 km. the level of Lake Agassiz stood about the level
of Austin its drainage changed from flowing
southward into the Mississippi and found an
outlet northward to Hudson bay.
105 m. Carberry — Altitude 1257 ft. (383 m).
169 km. Beaches marking a higher stage in the level
of the lake are crossed by the railway before
reaching this point, but they are indistinct
and not well marked. They may however
be found at the following points: at 86.9
miles (27 km.) from Winnipeg is the lower
Campbell beach; at 87.5 miles (26.6 km)
the upper Campbell beach. Immediately west
of Carberry the Herman beaches are to be seen.
132 m. Brandon — Altitude — 1199 ft- (365 m-)- The
212 km. evidences of Lake Agassiz are very slight at
Brandon and as it is situated on the estuary
of the ancient Assinboine river at the highest
stage of the lake, delta deposits only can be
found.

157 m. Griswold — Altitude 142 1 ft. (433 m.).

253 km. Slight evidences of morainic material occur
between Brandon and Griswold which mark
the position of the ice front when glacial Lake
Souris was in existence. This lake had not the
dimensions of Lake Agassiz. It drained south-
ward by the Pembina river.

264 m. Broadview — Altutude 1961 ft. (598 m.).
425 km.

356 m. Regina — Altitude 1884 ft. (564 m.). Regina

573 km. is the seat of government for the province
of Saskatchewan and is situated on a level
plain near the western edge of the second prairie
steppe.

398 m. Moosejaw — Altitude 1766 ft. (53 8m.). To
640 km. the south and west of Moosejaw the low rounded

Kilometres kills °^ ^e C°teau can be seen rising somewhat
abruptly from the level prairie. These hills
are the erosion remnants of Tertiary deposits.
South of Moosejaw are exposures of white
silts and clays, and important deposits of fire
clay. Coal seams also occur in these measures.
424 m. Mortlach — Altitude 1975 ft. (602 m.). The
682 km. cuttings along the railway here show deposits
of boulder clay in irregular shaped hills. Small
pebbles occur in the clay, and large boulders
appear at the surface.
433 m. Parkbeg — Altitude 2062 ft. (628 m.). The

697 km ascent to the third prairie steppe is made
through a gap in the hills of the Coteau,
and glacial drift is much in evidence which,
however, here shows an admixture of material
derived also from the underlying sandy beds.
Six miles (9 . 6 km.) west of Parkbeg the boulder
clay encloses a body of sandstone evidently
removed from the rocks beneath. Morainic
material is spread all along the eastern face
of these hills, and it is still an open question
whether the drift farther west was deposited
by floating ice or by a farther advance of the
glacial ice front.
508 m. Swift Current — Altitude 2,420 ft. (736 m.).
817 km. Beyond Parkbeg the railway follows the plain
which slopes northward from Cypress hills and
which is underlain by rocks belonging to the
Pierre division of the Cretaceous. At Forres

station

612 m. Forres — Altitude 2,465 ft. (751 m.). the Belly
985 km. River
series comes to the surface, and the rocks of
which it is composed outcrop in the hillsides
all the way to Medicine Hat. Sections of
these rocks are best seen at Redcliff on the
noith side of the valley of South Saskatchewan
river. Near the town and to the east of it the
river banks show a great thickness of till.
656 m. Medicine Hat — Altitude 2,168 ft. (661 m.).
1,056 km. Natural gas has been found in the lower part
of the Belly River series and also in the sandy
beds of the continuation of the Dakota. At
35069—7

Kilometres Medicine Hat the supply is all drawn from
depths between 400 (122 m.) and 1,000 feet
(304 m.). Gas for various manufacturing
processes and power, as well as for heat and
light, is available. The city has several wells
1,000 feet (304 m.) in depth with a pressure of
560 pounds capped. Three of these are capable
of furnishing 5,000,000 cubic feet of gas per
twenty-four hours. Gas is also supplied by
several privately owned wells. One owned by
the Canadian Pacific railway supplies their shops
with 1,250,000 cubic feet per twenty-four hours.
662 m. Redcliff — Altitude 2,428 ft. (740 m.). Brick

1,065 km. and other clay products are manufactured at
this point at two separate plants, and the burn-
ing is done by natural gas. The clay used is
from the Belly River formation. To the south
the Cypress hills are in view.

Between this point and Calgary the Canadian
Pacific Railway company has undertaken to
irrigate a large area of farm land, drawing water
through large irrigation ditches from the Bow
river at Calgary and Bassano.
722 m. Brooks — Altitude 2,476 ft. (755 m.). The

1,162 km. top of the Belly River formation is reached at
this station. To the west the Rocky Buttes
rise in a line of hills marking the eastern edge
of the sandy deposits of the top of the Creta-
ceous. The dark shales of the Pierre (the
Bearpaw of Montana) underlie the country to
Bassano.

745 m. Bassano— Altitude 2,584 ft. (788 m.). The
1,213 km. eastern edge of the Edmonton series is crossed
near Bassano. To the south is the valley of
Bow river.

762 m. Crowfoot — Altitude 2,698 ft. (822 m.). Coal
1 ,226 km. seams occur in the valley at this place and
are mined to some extent by the Blackfoot
Indians. These Indians hold in reserve a large
block of land to the south of the railway, and
the government maintains an agent at Gleichen
to teach them farming and to oversee the
providing of food and clothes for the aged.

Miles and
Kilometres.

816 m. Langdon — Altitude 3,289 ft. (1002 m.). Im-
,313 km. portant towns have grown up along the railway
as the result of the irrigation of this section by
the Canadian Pacific Railway company.

836 m. Calgary — Altitude 3,425 ft. (1044 m.). This
,345 km. fast growing city is becoming a railway centre
and manufacturing town. Tertiary rocks of the
Paskapoo series, outcrop in this vicinity and
are quarried for building stone.

859 m. Cochrane — Altitude 3,748 ft. (1142 m.).

,382 km. Here the railway line follows closely the valley
of Bow river, which cuts through the sandstones
of the Paskapoo series. At Cochrane the beds
dip east and form part of the great syncline
occupied by Tertiary rocks. The underlying
coal-bearing beds are brought up to the surface
and at Radnor a seam in the Belly River forma-
tion is being mined. Many flexures and folds
occur between this point and the mountains.

890 m. Kananaskis — Altitude 4,218 ft. (1285 m.).
,432 km.

In the hills immediately north of this station,
limestones of the top of the Cambrian have been
overthrust on Cretaceous of the Belly River
formation.

893 m. Exshaw — Altitude 4,247 ft. (1294 m.).

,437 km. Cement manufacturing is the principal indus-
try at this point and the plant is one of the
largest in Canada. Limestone is quarried from
the mountain side, but shale is now being
brought from near Laggan.

903 m. Canmore — Altitude 4,283 ft. (1305 m.).

,453 km. This town is situated on the western edge of one
of the wide fault blocks from which a great
section of Lower Cretaceous has been eroded
in the formation of the valley. Southward
along the mountain front remnants of these

100

Kilometres De^s occur- A narrow westerly dipping fringe
of the coal bearing beds is being mined below
the surface at this point. Behind the town,
cliffs of Devonian and Carboniferous limestones
show the eastern edge of the succeeding fault
block.

916 m. Bankhead — Altitude 4,569 ft. (1393 m.).

1,474 m. In front of Cascade mountain the continuation
of the coal measures forms a buttress in which
the beds dip towards the fault line. Mining is
carried on by an entry driven from the valley
level. The cross-cut tunnel from this entry
cuts the measures and intersects several seams.

The measures in which these seams occur
constitute a block dipping to the southwest
toward Cascade mountain. At the south end
of the block they pass under the limestone. At
the north end, up Cascade river, the measures
are bent up in a syncline, but further on
they have been entirely eroded away.

A section measured near the mine at Bank-
head gives a total thickness of 2,800 feet (853)
of possibly coal bearing rocks, with 550 feet
(167 m.) of thin bedded brown sandstones
and shales above them. The measures consist
of sandstones and shales of a generally brown
colour, and, in this vicinity, three of the heavy
sandstone beds form strong ribs. The upper
and lower sandstone ribs seem to define the
upper and lower limits of the coal formation,
which has a thickness of 1,100 feet (335 m.).
Below is a series of sandstones and shales
very similar to those higher up. The passage
to the Fernie shales is conformable, and is
marked by an absence of sandstone. The
Fernie shale consists of 1,360 feet (445 m.)
of dark grey to black shale overlying 240 feet
(73 m.) of dark greyish thin-bedded sandstone,
the whole of marine origin and assigned to the
Jurassic period. These beds are exposed on
the river sides above the mine.

101

The following tabulai statement shows the thickness
of the coal seams and associated beds and th~ir succession :-

Seam No. o.

Thickness between roof anc floor . . .

Coal

Thickness between No. Ou. j No. : .

Seam No. i.

Thickness between roof ard flo«.

Coal in thin bands

Thickness betv. . No. 2

Seam No. 2.

Thickness between roof z nd floor. . .

Coal (one clean part, 8 ft.)

Thickness between No. 2 and No. 3.

Seam No. J.

Thickness between roof and *loor . . .
Coal (two benche^ 14 fv. and 5 ft.)..
Thickness between No. 3 and No. 4.

Seam No. J+.

Thickness between roof and floor

Coal (in three benches 6 ft., 3 ft., 4-5 ft.)
Thickness between No. 4 and No. 5

Seam No. 5.

Thickness between roof and floor.
Coal (in the top part)

Feet.

3
33

12
7
30

18
10
92

29
19
50

17
13

12
6

Inches.

o
1 1

GUIDE BOOK No. 8

Transcontinental Excursion ci

Toronto to Victoria and return via
Canadian Pacific and Canadian
Northern Railways

PART II

ISSUED BY THE GEOLOGICAL SURVEY

OTTAWA

GOVERNMENT PRINTING BUREAU
1913

GEOLOGY LIBRARY

105

GUIDE BOOK No. 8.
Part II.

CONTENTS.

PAGE.

Introduction to the Geology of the Cordillera,

by Reginald A. Daly in

General topography in

Glaciation of the Cordillera 116

General stratigraphy 117

Columnar section 118

Shuswap terrane 122

Shuswap series 122

Orthogneisses and intrusive granites. ... 126

Beltian system 132

Cambrian system 138

Ordovician system 142

Silurian system 143

Devonian system 143

Mississippian system 143

Pennsylvanian system 144

Permian system 145

Triassic system 145

Jurassic system 145

Cretaceous system 147

Eocene system 148

Oligocene system 148

Pleistocene system 149

General structure 149

Note on the igneous bodies 154

General history 157

Specially noteworthy features 164

Bibliographic note 165

Rocky Mountains (Bankhead to Golden),

by John A Allan 167

Stratigraphy 167

Columnar section 167

35069— 1 §a

io6

PAGE.

Pre-Cambrian 172

Corral Creek formation 172

Hector formation 174

Cambrian 174

Lower Cambrian 174

Fairview formation 174

Lake Louise formation 175

St. Piran formation 175

Mt. Whyte formation 175

Middle Cambrian 176

Cathedral formation 176

Stephen formation 176

Eldon formation 178

Upper Cambrian 178

Bosworth formation 178

Paget formation 178

Sherbrooke formation 179

Chancellor formation 179

Ottertail formation 179

Ordovician 179

Goodsir formation 179

Graptolite shales 181

Silurian 181

Halysites beds 181

Devonian 181

Intermediate limestone 181

Sawback formation 182

Mississippian 182

Lower Banff limestone 182

Lower Banff shale 182

Pennsyl vanian 1 83

Upper Banff limestone 183

Rocky Mountain quartzite 183

Permian 183

Upper Banff shale 183

Jurassic 184

Fernie shale 184

Cretaceous 185

Lower Ribboned sandstone 185

Kootenay Coal Measures 185

Upper Ribboned sandstone 185

Post-Cretaceous 185

Igneous complex 185

io7

PAGE.

Pleistocene and Recent 186

Annotated guide, Bankhead to Golden 186

Bibliography 201

Annotated Guide, Golden to Savona,

by Reginald A. Daly 202

Western Part of the Belt of Interior Plateaus,
Savona to Lytton,

by Charles W. Drysdale 234

Essential geology 234

Introduction 234

Physiography 235

Glaciation 237

Stratigraphy 239

Summary history 242

Annotated guide 243

Coast Range, Lytton to Vancouver,

by Charles Camsell 256

Introduction 256

Columnar sections (by Norman L. Bowen) .... 257

Canyon of Fraser river 259

Physical features 259

Geology 260

Origin and history of the canyon 261

References 264

Annotated guide, Lytton to Agassiz 265

Fraser delta 271

Topography 271

Geology 272

References 272

Annotated guide, Agassiz to Vancouver 273

io8

ILLUSTRATIONS TO PART II.
Maps.

PAGE.

Sketch map showing major subdivisions in the southern part

of the Canadian Cordillera 112

Banff 189

Laggan-Field (in pocket)

Route map between Banff and Golden 189

Route map between Golden and Revelstoke 203

Prairie Hills and Dogtooth Mountains 205

Glacier (in pocket)

Albert canyon 215

Map showing approximate distribution of the Shuswap terrane

rocks in south central British Columbia 219

Route map between Revelstoke and Ducks 221

Route map between Ducks and Lytton 245

Route map between Lytton and Agassiz 265

Route map between Agassiz and Vancouver 274

Drawings and Sections.

Diagram showing metasedimentary schists, thin limestone
interbeds, and intrusive sills of the Shuswap terrane; typical
relations; locality near Carlin siding 126

Cliff section of aplitic dykes cutting paragneiss (?); Shuswap

terrane at Clanwilliam 130

Diagram drawn to scale, showing development of columnar

jointing in Tertiary basaltic flow near Ducks station 163

Section illustrating great crumpling of Glacial silts by advancing
ice sheet which deposited typical till on the silts. Locality
3-5 km. west of Cherry Creek station 234

Photographs.

Looking south-east from Six Mile Creek along the Purcell

trench (Beaver river valley) 114

Looking south from Terminal Peak along the edge of the great

escarpment bounding the Purcell trench on the west 115

Bastion mountain from the west, showing the Sicamous lime-
stone (in the high bluff) overlain by the Bastion schists
(background, on the left). The large out crop near the
middle of the view is intrusive syenite 125

Aplitic and pegmatitic sills cutting rusty metasedimentary schists
and limestone interbeds; Shuswap terrane, western shore of
Mara Arm of Shuswap lake 127

Schistose structure of typical orthogneiss in Shuswap terrane,
illustrating static metamorphism. The hammer is about
32 cm. in length. Locality, Albert Canyon station 129

Strain-slip cleavage in talc schist of the Shuswap series, at Blind
bay. The well developed, low-dipping schistosity is due to
earlier static metamorphism. Camera case about 7 cm.
thick 131

Top of Cougar mountain, looking southeast; showing Cougar

quartzite as typically developed in the Selkirk range. . . . 135

109

PAGE.

Summit of the Dogtooth range, looking east from a peak near
head of Quartz creek. Slopes underlain by the Ross forma-
tion as typically developed in the Purcell mountains 139

Summit of Mt. Tupper from Tupper Crest, showing characteristic
habit of the Sir Donald quartzite. Photograph by Howard
Palmer 140

Characteristic outcrop of Triassic (Nicola) basalts near Ducks
station. The terrace is composed of the white Thompson
River silts 146

Looking south from Mt. Tupper to Mt. MacDonald and Mt. Sir
Donald (background), showing part of the summit sync line
of the Selkirks as shown in the Sir Donald quartzite forming
the great escarpment. Photograph by Howard Palmer... . 151

Drag folds in the Cougar quartzite near head of Cougar creek,

Selkirk range. Cliff shown is about 15 m. in height 152

Looking north over the South Thompson river, from Campbell's
ranch, 9 km. west of Ducks station. The creek bed in the
middle of the view is located on the plane of unconformity
between Pennsylvanian limestone (left, light-coloured
outcrops) and Triassic conglomerate and basalt (right,
dark-coloured outcrops) 155

Contact of the Pre-Cambrian shales (Hector) and the Lower
Cambrian quartzites. Exposed in Bath creek, west of
Laggan 173

Mt. Temple showing complete Lower and Middle Cambrian
section, capped by Upper Cambrian and underlain by Pre-
Cambrian shales (covered by talus) 175

Castle Mountain, showing Cathedral limestone in the lower

cliffs; Stephen formation in the talus covered slope; and the
Eldon formation in the upper cliffs. (All Middle Cambrian) 176

Fossil bed in " Burgess shale" on Mt. Field, showing character
of the shale, method of quarrying for fossils, and tempor-
ary camp of C. D. Walcott 177

The Mitre and Death Trap (pass) to the right. The cliffs on the
right are of Middle Cambrian limestone in Mt. Lefroy.
A typical bergschrund is shown around this portion of the
Lefroy glacier 178

Cambrian-Ordovician contact in Mt. Goodsir. The grey rock
is the Ottertail limestone, overlain by the dark -coloured
Goodsir shales 180

A typical view of the Upper Banff shale, exposed in Spray valley

at Banff 184

Ottertail escarpment showing Chancellor formation forming
talus covered undulating surface; Ottertail limestone in
cliffs; and the Goodsir shales on gradual slopes 199

Mt. Tupper from Rogers pass. Slopes underlain by Sir Donald

quartzite 208

Illecillewaet glacier in August, 191 1. Photograph by H. Ries. . 210

Illecillewaet glacier in August, 19 12. Comparison with preceding
figure shows recession of the ice-front during the year
preceding. Photograph by H. Ries 210

Mt. Sir Donald from Eagle mountain; Mt. Uto in foreground.

Photograph by Howard Palmer 211

PAGE.

Orthogneiss near Albert Canyon; schistosity due to static meta-

morphism 217

Quartzites, mica schist and paragneisses, showing coincidence of
bedding and schistosity; Shuswap series. At Summit lake,

Columbia range, in railway section 223

View in belt of Interior Plateaus, looking westerly down Shuswap

lake near Blind bay 225

Silt terraces on South Thompson river, with Pennsylvanian

formations (Cache Creek series) in the background. Look-
ing north from a point about three miles above Kamloops 229
View showing the character of the topography about Ashcroft. 247
Looking up Thompson valley towards Ashcroft; Spatsum siding

in the bottom of the valley 250

Junction of Nicola and Thompson valleys, near Spence's Bridge 252

Scarped north wall of Thompson canyon near Gladwin 255

Looking southwest from Mt. Ferguson, Lillooet district, showing

mountains typical of the Coast range 257

Entrance to Fraser canyon above Yale, with Lady Franklin

Rock in the middle of the stream 259

Fraser river, looking down from Yale; valley here widened out

on greatly sheared granite of the Coast Range batholith . . 263
Constriction of Fraser river at Hell's Gate near China Bar.

The ledges are composed of jointed granodiorite 267

Ill

INTRODUCTION TO THE GEOLOGY OF THE
CORDILLERA.

Reginald A. Daly.

GENERAL TOPOGRAPHY.

The North American Cordillera, extending from Bering
Sea to the intersection with the Antillean mountain system,
has a length of 7,000 kilometres (4,350 miles), an average
breadth of about 900 kilometres (560 miles), and an area
more than two-thirds that of all Canada and nearly two-
thirds that of Europe. This gigantic feature of the earth is
a tectonic unit, originating in stresses specially exerted
from the Pacific basin. The Cordillera as a whole has,
therefore, been fitly called the Pacific Mountain system
of North America.

The members of Excursion Ci. will cross the system
where it is comparatively narrow; nevertheless, a straight-
line measurement of its width is here about 700 kilo-
metres (435 miles). Along the somewhat tortuous route
of the Canadian Pacific railway, the distance from the
eastern foot of the mountains to the city of Victoria is 1 ,050
kilometres (650 miles). For purposes of geological
description and of orientation in the field, it is necessary to
review the general subdivision of the Pacific Mountain
system at the railway section.

Among the conceivable criteria for subdivision, the
purely topographic principle used by G. M. Dawson seems
to be the only practical one. In the first place we may
distinguish a belt characterized by plateau forms and
thereby contrasted with the rest of the Cordillera in the
Dominion of Canada. This may be called the Belt of
Interior Plateaus. It lies on the eastern side of the Coast
range, which is of alpine habit. Elsewhere the subdivision
of the mountain chain follows the lines of the master valleys.

The greatest of the intermont depressions is that
extending from Flathead lake in Montana to the Yukon
boundary, a distance of 1 ,600 kilometres (990 miles) . It is a
relatively narrow but actually imposing trough, successively
drained by head-waters of most of the great rivers of the

Canadian part of the chain: namely, the Columbia, Fraser,
Peace and Liard — the last two being principal branches
of the Mackenzie river. The larger streams flowing in the
depression are: the Kootenay; the Columbia; the Canoe
river; the Fraser; the Parsnip and Finlay rivers (Peace
river system) ; and the Kachika river of the Liard system.
Many of them leave the trough by transverse gorges
cut in the adjacent mountains. The rivers enumerated,
as well as smaller ones not specially named, are arranged
in regular sequence, draining the trough in opposite
(N.W. and S.E.) directions. Although continuous
throughout its great length, the trough is not a valley
in the ordinary sense. It is like a trench dug by soldiers
in a hilly country; such a defensive work is not cut to
a uniform bottom grade but is man-deep whatever the
slope. This master form in the Cordillera may be appro-
priately described as a topographic trench. All the
mountains in Canada and in Montana lying to the north-
eastward of the trench have long been segregated as the
Rocky Mountain system, and the bounding trough has
been named the Rocky Mountain trench.

A second trench, about 350 kilometres (220 miles) in
length, opens in the southeastern wall of the first near
Bea vermouth and runs southward. It is successively
drained by Beaver river, Duncan river, and Kootenay
river; for 120 kilometres (74 miles) it is occupied by the
fiord-like Kootenay lake. This trough rigorously separates
the Purcell Mountain range on the east from the Selkirk
system on the west and bears the name, Purcell trench.
The Purcell range is thus bounded, east and west, by
the two trenches; on the south it terminates at the loop
of the Kootenay river in Montana and Idaho.

Near latitude 520 the Columbia river leaves the Rocky
Mountain trench and flows south, in a wide valley 500
kilometres (310 miles) long, to the Columbia lava- field of
Washington State. This part of the Columbia valley
may for convenience be called the Selkirk valley. Mid-
way in its course it bears the Arrow lakes, totalling 150
kilometres (92 miles) in length. East of the Selkirk
valley and west of the two master trenches is the Selkirk
Mountain system which, like the Rocky Mountain and
Purcell systems, extends into the United States.

The rugged mountains to the west of the Selkirk
valley have been grouped under the name, Columbia

mountain system. On the north this system is bounded
by the obliquely truncating Rocky Mountain trench; and
on the south by the lava plateau of Washington. Toward
the west the Columbia mountains become less alpine and
assume a rough-plateau character, so that it is not possible
to make a clean-cut line of division from the adjacent
Belt of Interior Plateaus. This zone of topographic
transition is crossed by the railway in the region of the

Looking south from Terminal Peak along the edge of the great escarpment bouncing
the Purcell Trench on the west.

Shuswap lakes. The Fraser valley at and in the vicinity
of Lytton forms a convenient and more definite limit
to the Belt of Interior Plateaus, on the west.

The Coast range extends from the Fraser valley to
the structural depression occupied by the Strait of Georgia
and Queen Charlotte sound, to the westward of which
is the Vancouver range of Vancouver island. On the
south the Coast range terminates at the transverse portion
of the Fraser valley, which also delimits the Cascade range
entering British Columbia from the United States.

In the larger view, the Canadian Cordillera may be
broadly divided into four provinces: (a) the Rocky
Mountain system; (b) the Middle or Interior ranges,
including the Purcell, Selkirk, Columbia and Cariboo moun-
tains; (c) the Belt of Interior Plateaus; and (d) the
Coastal system, including the Coast range, the Cascade
range, and the Vancouver-Queen Charlotte range. The
first, third, and fourth of these provinces extend, with but
minor interruptions, through Yukon Territory and Alaska
to Bering Sea. The Middle ranges as a whole are specially
broad in southern British Columbia, but narrow rapidly
to the northward and, in the United States, have been
broadly depressed and covered by the lava floods of Idaho
and Washington states.

GLACIATION OF THE CORDILLERA.

The field habit of the visible glaciated rock-surfaces
and the condition of the drift deposits, in these Canadian
mountains, strongly suggest that the great glaciers of the
Cordillera were essentially contemporaneous with the
eastern ice-cap at its Wisconsin stage. No facts yet
determined on the mainland of British Columbia or in
Alberta have shown clearly that general Pleistocene
glaciation was multiple. It is true that, afc many points
within the Cordillera and along its piedmonts, younger
till rests on water-laid silts, sands, or gravels of Pleistocene
age; but this relation is that normal to the inevitable
oscillation of ice-fronts during a single glacial period and
it is still unsafe to postulate a general interglacial epoch
for the Cordillera. However, further investigation of its
interior portion may demonstrate one or more interglacial
periods, even in spite of the fact that, in a topography
so strongly accidented, a more recent glaciation must
tend to obliterate the traces of an earlier one.

When at their maximum, the Pleistocene glaciers
of the mainland formed an interior ice-cap flanked by
double rows of valley glaciers. The ice-cap was fed by the
local sheets respectively draining the western versant of
the Rocky Mountain system and the eastern versant of
the Coast range. The eastern slope of the Rockies was
drained by many large valley glaciers. These often
became confluent as piedmont sheets on the plains of

ii7

Alberta. Similarly, the western slope of the Coast range
bore heavy glaciers which formed thick and broad pied-
mont sheets filling Puget sound, the Strait of Georgia,
and Queen Charlotte sound.

Dawson located the main accumulator of the ice-cap
in the interior of the Cordillera between latitudes 540 and
590, and proved the northward flow from that region
as far as 630 N., as well as a southward flow over the 49th
parallel into Washington State. Locally, the ice-cap
sent thick distributary sheets through low cols and valleys
crossing the Coast range; of these the Fraser valley is
a signal instance. At many points the surface of the en-
era ice-cap is known to have risen somewhat above the
7,000-foot (2,134-metre) contour. Its thickness at the
Okanagan valley was at least 6,000 feet (1,830 m.) ; at
Revelstoke about 5,500 feet (1,677 m0-

Nothwithstanding its massive proportions, the ice-
cap performed comparatively little erosion. Area for area,
this necessarily sluggish body was incomparably less power-
ful in cutting into bed-rock than were the neighbouring
valley glaciers. These were usually much swifter because
occupying lines of more concentrated flow. The influ-
ence of such concentration, caused by mountainous topo-
graphy, is extremely clear in the Canadian Cordillera,
and the principle leaves no ground for controversy as to
the efficiency of glacial erosion.

A smaller, independent ice-cap covered Vancouver
island, and another, or else a large number of local glaciers
occupied the Queen Charlotte islands.

GENERAL STRATIGRAPHY.

The section along the Canadian Pacific railway offers
an almost complete representation of the main rock systems
known in the Canadian Cordillera. The variety of the
formations is explained partly by the transverse character
of the section through a belted mountain chain; partly
by the specially extensive uplift and exposure of the oldest
rocks in this geological province. Only the Pliocene and
the Miocene fail to appear in the list of standard rock
systems, which here ranges from the Pre-Cambrian (pre-Bel-
tian) to the Pleistocene. In the succeeding table the more
important formations, with thicknesses, are named in

order. The measurements and estimates are founded
on considerable, more recent field-work supplementing
the reconnaissance studies of G. M. Dawson. [5, p. 62].

The total of the maximum thicknesses is colossal
(135,000 feet (41,150 m.), including 25,000 feet (7,620 m.)
of volcanics), but there can be no doubt that it is correct
as to the order of magnitude. Notwithstanding all possible
errors of mensuration, it seems clear that the Beltian-
Paleozoic geosynclinal prism of the Selkirk- Rocky Mountain
region had a thickness greater than 50,000 feet (15,240 m.).
Dr. J. A. Allan has found more than 40,000 feet (12,192
m.) of conformable sediments in the Rocky mountains.
The still older strata of the Selkirks are nearly or quite as
thick.

TABLE OF CORDILLERAX FORMATIONS.

System.

Formation.

Thici
Feet.

:ness.
Metres.

Recent and

Pleistocene

Fluviatile, lacustrine,
glacial

Unconformity.

Oligocene (?)

Kamloops volcanic group
Tranquille beds (largely

tuffs)

Unconformity.

3.000+
1 ,000

914+
305

Eocene

Coldwater group (con-
glomerate, sandstone,
etc.) of Interior

Puget group of Coast. . .

Rhyolite porphyry at

Ashcroft

Unconformity

5.000

524

TABLE OF CORDILLERAN FORMATIONS — Continued.

System.

Formation.

Thici
Feet.

CNESS.

Metres.

Lower Cretaceous
(Comanchean) ....

Jackass Mountain group
and Queen Charlotte
Islands group (sand-
stones, shales, con-
glomerates) of the

Upper Ribboned sand-
stone

Kootenay Coal Measures

" Rocky Mts

Lower Ribboned Sand-

Spence's Bridge Volcanic
group

s^o

2 ,800
I ,000

168
853
305

Jurassic

Fernie shale of Rocky
Mts

Upper part of Nicola
group (Interior)

I ,500

457

Triassic . .

Uncon+or

Lower part of Nicola
group (basic volcanics
with limestone

Boston Bar group of
Coast range (Triassic?)

tnity with Penny slvanian.

I0,000=f

3,048^=

Permian

Upper Banff shale

1 ,400

427

Rocky Mountain quart-
zite (thickness, 244m.)
Upper Banff limestone

Cache Creek group of the
Western Belt (quart-
zite, limestone, basic

j Rocky M
9,500

ts.

2,896

35069— 2A

120

TABLE OF CORDILLERAN FORMATIONS — Continued.

System.

Formation.

Thice
Feet.

:ness.
Metres.

Mississippian

Lower Banff limestone
(partly Devonian) ....

I ,200

i ,500

366
457

Devonian

Intermediate limestone. .
Sawback limestone (Dev-
onian?); (thickness,

1 ,800

548

Silurian

1,850

563

Ordovician

Graptolite shale

1 ,700
6,040

5i8
1,841

Upper Cambrian. . . .

Ottertail limestone

Chancellor shales

Sherbrooke limestones. . .

Bosworth limestones ....

1,725
4,500

i,375
360

i,855

526
i,372
419
no
565

Middle Cambrian . . .

Eldon limestones

Stephen limestone-shale
Cathedral limestones. . . .

2,728
640
i,595

831
196
486

Lower Cambrian ....

Mt. Whyte sand-'
stone shale ....

St. Piran quart-
zite

Rocky
Mts.

Lake Louise shale
Fairview sand-
stone

121

TABLE OF CORDILLERAN FORMATIONS — Concluded,

Thickness.

System.

Formation.

i cel.

IVICLI Cb.

Sir Donald quart-1 Sel-

5,000

1.524

zite [ kirk

Ross quartzite, \ Mts.

2,750

838

upper part J

i nyifnyyyiit'v iyi 'splhiYb

\J f LJ \J 1 III l/t/V If 11/ k^J c^tfvti /v

Mts\ local unconformity

in Rocky Mts.

Beltian

Ross quartzite (lower

part)

2,500

762

Nakimu limestone

35o

I07

Cougar quartzites

10,800

3»292

15,000

4.572

Illecillewaet quartzite.

1,500

457

fyloose metargillite

2,150

655

Limestone

170

Basal quartzite

280

Unconformity .

Pre-Beltian

Adams Lake greenstones

10,000

3,048

(Shuswap scries)

Tshinakin limestone-

metargillite

3,900

1,188

Bastion schists (phyllites,

6,500

1,981

3,200

975

Salmon Arm mica schists.

1 ,800

548

Chase quartzite

3,000

914

Tonka watla para-

1,500

457

Base concealed.

Total thickness (minimum)

135,018

41.150

35069— 2 |a

122

The more important volcanic formations are listed
in the table. A few subordinate bodies of lavas and pyro-
clastics, together with very numerous intrusive masses,
will be noted in the sequel. Igneous activity is registered
in the pre-Beltian, Beltian, Palaeozoic, Mesozoic, and
Cenozoic eras.

Shuswap Terrane.

Detailed work has been only begun on the widely
exposed pre-Beltian rocks, which form the crystalline base
ment of British Columbia and share the complexity of
the "Archean" in all parts of the world. They consist
of a very thick, conformable, bedded group, called the
Shuswap series, and a younger group of granitic intrusives.
The whole complex may be conveniently named the
Shuswap terrane.

Shuswap Series — Owing to structural difficulties,
to the ruggedness of the mountains, and especially
to a dense forest cover, it has not yet proved possible
to construct a definitive columnar section for the Shuswap
series. It is best exposed on the shore-lines of the Shuswap
lakes and of Adams lake, during the low-water season
of the year. However, one can seldom follow a contact
or other structural plane far from the lake shore. Faults,
thrust-planes, and folds are unusally difficult to map
in this thoroughly metamorphosed mass of sediments
and volcanics. Neither the top nor the bottom of the
series has been found. The oldest sediments are inter-
leaved with, and underlain by, intrusive granites, chiefly
developed as sills. The youngest member on Adams
lake where it is best exposed, is truncated by the present
erosion surface.

Obscure as the structures generally are, it is quite
clear that the Shuswap series is exceedingly thick. A
provisional columnar section may be stated, as follows:

123

Tentative Columnar Section of the Shuswap Series.

Thickness.

Top, erosion surface. Feet. Metres.

Adams Lake formation; greenstone schists. 10,000 3,048
Tshinakin formation:

Limestone (1,500 ft., 457 m.)
Phyllitic metargillite (800 ft., 244 m.)
Limestone (1,600 ft., 488 m.)

Total 3,900 1,188

Bastion schists, phyllite with green schists

at top 6,500 1,981

Sicamous limestone 3,200 975

Salmon Arm schists, nrcaceous 1,800 547

Chase quartzite 3, 000 914

Tonkawatla paragneiss 1,500+ 457 +

Base concealed

29,900 9,111

The Tonkawatla formation is exposed in a series of
railway cuts 3 miles (5 km.) west of Revelstoke. It con-
sists of a dark-coloured, massive, homogeneous, compara-
tively fine-grained gneiss bearing thin interbeds of white
crystalline limestone. The latter are seldom over 2 inches
(5 cm.) in thickness but are locally numerous. Their
presence suggests that the whole group of rocks here
exposed is of sedimentary origin. The gneiss is rich in
biotite and plagioclase and is probably best interpreted as
originally a calcareous argillite. The paragneiss passes
upward into yet more massive, harder biotitic quartzite,
which also carries thin intercalations of limestone.

Quartzite of identical habit and tentatively ascribed
to the same horizon, is exposed on the slope due south of
Shuswap station near the village of Chase. Here the
thickness is to be measured in hundreds of metres and a
special name, Chase quartzite, has been given to the mem-
ber. Besides the thin beds of limestone, the quartzite
often shows abundant disseminated grains of carbonate,
largely calcite.

At Shuswap station the massive Chase quartzite is
directly overlain by coarse, glittering muscovite-biotite
schist, often garnetiferous and seamed with beds of mica-
ceous quartzite. As usual in the Shuswap series, the planes

124

of bedding and schistosity are coincident. A thickness
of some 1,500 feet (457 m.) is locally represented in these
schists. They appear to be of the same horizon as a group
of schists exposed in still greater strength on Salmon Arm
of Shuswap lake; the name Salmon Arm schist may be
given to the member. The coarse crystallization of the
plainly sedimentary formation is due to the contact meta-
morphism of countless granitic sills and laccoliths. On
the cliffy slopes at the eastern end of Bastion mountain
the coarse schists pass up gradually into phyllite, a less
metamorphosed phase.

On the slope just mentioned the Salmon Arm schists are
conformably overlain by the thick Sicamous limestone,
named for its occurrence at Sicamous station. This is a
thin-platy, light bluish-gray to dark gray or almost black
limestone, generally interrupted by closely spaced sericitic
films. The range in colour tints is due to variation in the
amount of carbonaceous matter disseminated through
the limestone. The rock effervesces with cold dilute acid,
but it is somewhat magnesian.

The western slope of Bastion mountain is in part under-
lain by the Bastion schists conformably overlying the
Sicamous limestone These are best exposed on the shore
of the lake, north of Canoe point opposite Sicamous.
They are chiefly sedimentary phyllites but at the top are
green schists, apparently of volcanic orgiin.

On Adams lake, schists like the last-mentioned rocks,
are conformably overlain by the composite Tshinakin
formation, which, in turn, is there conformably overlain
by a gigantic series of greenstones and green schists, the
Adams Lake formation, enclosing rare interbeds of lime-
stone and phyllite. To this youngest recognized member of
the Shuswap series Dawson gave the name "Adams Lake
series", and he regarded it as of Cambrian date and of
volcanic origin. More recent work has referred it to the
Pre-Beltian series. Dawson estimated the thickness of
these volcanics as 25,000 feet (7,620 m.) ; the apparent
thickness is certainly greater than 10,000 feet (3,048 m.).

No complete field section has yet been found in the
great Shuswap terrane and several of the horizons have
been brought into the described relations through litho-
logical similarities in different sections. That principle
is of specially hazardous application in a region of complete
metamorphism like that now under consideration. The

126

table of formations will therefore surely need emendation.
Nevertheless, it will serve to give a picture of the leading
stratigraphic inferences so far made and to indicate in a
qualitative way the magnitude and variety of the forma-
tions composing the Shuswap series.

Metres

o I 2 3 +. 5

Diagram showing metasedimentary schists, thin limestone interbeds, and intrusive
sills (left blank) of the Shuswap terrane, in typical relations; locality near
Carlin siding.

Orthogneisses and Intrusive Granites. — Without
exception each member of the Shuswap series has been
intruded by granitic magma of pre-Beltian age. Some
of the largest of these intrusive bodies are true cross-
cutting batholiths which have developed strong meta-
morphic aureoles. However, most of the intrusions, liter-
ally innumerable, are not subjacent or bottomless but
are to be classed with the 'injected' bodies. Sills are
specially conspicuous. Some of the injections are thick
and apparently of laccolithic form and mechanism; others
have roofs and floors, but cross-cut the bedded formations
and these may be described as chonoliths. Dykes are

128

very numerous, in part representing the feeding channels
for the other types of injection.

The injected bodies are, in part, clearly satellites of
underlying batholiths, but it is possible that many of
them are due to the migration of hydrous magmas locally
generated in the depths of a greatly metamorphosed
terrane.

The principal petrographic types in these intrusions
are : biotite granite (most abundant) ; hornblende-biotite
granite ; two-mica granite (rare) ; pegmatite and aplite
(both very abundant) ; and orthogneisses corresponding
to each of these magmatic species. Extended microscopic
study shows that there is little mineralogical novelty;
the rock types are duplicated in most of the 'Archean'
tracts on the globe and are usually gneissic in structure.

The extraordinary prevalence of sills and other concord-
ant injections is explained by the extreme fissility of the
Shuswap sediments and greenstones. This feature is
due to static metamorphism. As shown in the following
section on structure, the dips of the Shuswap terrane are
generally low. Though its rocks have passed through
several periods of energetic mountain-building, their
dips over large areas do not surpass 150 and their average
dip is probably no greater than 350. The metamorphism
is essentially as far advanced where the strata lie horizontal
as where they are dipping at angles of 6o° to 900.

Further, it seems highly probable that the fissility had
attained nearly its present perfection before the Beltian
system of rocks was deposited in the Shuswap terrane,
and thus at an early date in the earth's history. The
conditions for the metamorphism include: deep burial,
with consequent development of "stress" in the vertical
direction; and an abundant supply of interstitial water,
such as that originally trapped in the sediments and vol-
canic beds. The completeness of recrystallization, which is
much more striking than that visible in similar geosynclinal
rocks of Cambrian or later date, implies that at least one
other condition was here necessary. Hypothetically we
may find it in a specially steep thermal gradient, con-
trolling subsurface temperatures in pre-Beltian times.
Field evidence thus leads to the suspicion that the earth
was then notably hotter than it was later, when most of
the known thick_masses of_sediments were deposited.

132

Whatever be the explanation, it is clear that the Shuswap
series has not been seriously affected by dynamic metamor-
phism. The strata and most of the injected granites
were completely or almost completely recrystallized while
the strata lay nearly flat. In some localities the effects
of dynamic metamorphism have been superposed on those
due to previous static metamorphism. An example is
illustrated on page 131. Similarly, thermal metamorphism
produced by sills or batholiths is generally easy to dis-
tinguish from the prevailing regional type. Contact
action has either coarsened the grain of the invaded
formation or has developed hornfelses bearing minerals
characteristic of plutonic contacts. The older members
of the Shuswap series are, in general, more coarsely crys-
talline than the younger, partly because of deeper burial,
but more because of the greater abundance of intrusions
at the lower horizons.

BELTIAN SYSTEM.

Unconformably overlying the Shuswap terrane in the
Selkirk mountains is a vast thickness of conformable,
unfossiliferous sediments, for which as a whole the name,
Selkirk series, has been adopted. The lower and greater
portion of these beds is of pre-Cambrian age ; the uppermost
beds, as exposed in the railway section are referred, on
stratigraphic evidence, to the Lower Cambrian. The
group is clearly the northern continuation of the Belt
series of Montana and Idaho. To the Pre-Cambrian
portion of each series Walcott has applied the name
' Beltian ' as a systemic designation and it will be adopted
for present use.

In the railway section the Beltian is constituted of the
following members. :

133

Columnar Section of the Beltian System in the Selkirk

Mountains.

Approximate
Thickness.

Top, erosion surface.

Feet.

Metres.

Glacier Division

'Ross quartzite (in part) ....

2,500
350

10,800

762
107

3,292

{Selkirk series of
Dawson).

Cougar formation (quart-
zite with metargillitic beds)

Albert Canyon
Division
(Nisconlith series
of Dawson).

Laurie formation (metar-

crililff* C\\ tpn 1 r*o t*£±r\i ic •
^llllLCj \JL LC11 y^cLLKsCLL CUUo ,

with subordinate inter-
beds of limestone and
quartzite; basal bed, gray
limestone 15 m. thick). .

Moose metargillite

Limestone (marble)

Basal quartzite

15,000
1,500
2,150
170

280

4,572
457
655
52
85

Base, unconformity with Shuswap terrane.

32,750

9,982

In the railway section the basal quartzite is a greenish-
gray, fine-grained metarkose, a massive to well-bedded,
feldspathic rock of quartzitic habit, though strongly
charged with films of sericitic mica. The original material
was the somewhat washed sand due to the secular decompo-
sition of the underlying Shuswap orthognesis. It will be
described in greater detail in a following account of the
geology about Albert Canyon station.

At its top the quartzite is interleaved with the lowest
layers of the overlying limestone. This is a thin-bedded
to thick-bedded, white to bluish marble, generally weather-
ing to a pale buff colour. It is magnesian throughout,
though some beds are more purely calcitic than others.

The Moose metargillite has been so designated from an
older name of Albert creek, which enters the Illecillewaet
river at Albert Canyon station. The middle part of this
formation has not yet been found in satisfactory exposure

134

but the whole seems to be a fairly homogeneous argillite, 1
now largely recrystallized by static metamorphism — a
metargillite. All phases are charged with sericite, devel-
oped parallel to the bedding planes, and occasionally one
finds thin beds glittering with coarser mica like a normal
muscovite schist. The colour is generally gray, of a dark
tint due to disseminated particles of carbon.

The lllecillewaet quartzite is hard, gray, massive to fissile,
and relatively homogeneous except for thin intercalations
of metargillite. Unlike the basal quartzite, it is poor in
feldspathic material and evidently represents a more com-
pletely washed and assorted sediment.

In the monoclinal section between Albert Canyon and
Ross Peak stations, the Laurie formation (named after the
mining camp at the railway) is of most remarkable thick-
ness. Measurement on the actual outcrops gave the fol-
lowing succession.

Approximate

Thickness.

Feet.

Metres.

Base of the Cougar formation.

Gray, phyllitic metargillite

4,000

1 ,219

Quartzite

650

198

Black to dark gray metargillite

500

152

Alternating beds of phyllite and quartzite

750

229

Black to dark gray, carbonaceous, often pyr-

itous metargillite, with interbeds of blackish

limestone

9,300

2,835

Gray quartzite

400

122

Black to dark gray, strongly carbonaceous met-

argillite, with numerous interbeds of blackish

limestone

3,5oo

1 ,067

Massive, light gray limestone

Top of lllecillewaet quartzite.

19,150

5,837

There is no sign of important duplication by strike-
faulting, though some thickening is represented in local
crumples. Admitting all possible duplication suggested
by the facts now in hand, this formation must be credited
with a thickness of more than 15,000 feet (4,572 m.). On

35069— 3A

136

account of the general uniformity of composition and habit,
no satisfactory subdivision of the formation is yet feasible;
because of their limited exposure in the railway zone, the
quartzitic beds cannot be used for subdivision.

The Albert Canyon division of the Selkirk series is
thus chiefly of metargillitic composition. The overlying
Glacier division, more especially as it crops out on the wes-
tern slope of the Selkirk range, is dominantly quartzitic.

Its most heterogeneous member is the Cougar formation,
named from Cougar mountain, in which it is exposed on a
great scale. In the monocline between Caribou creek and
the Caves of Cheops (Nakimu), the formation shows the
following general succession.

Columnar Section of the Cougar Formation.

Thickness.

Feet.

Metres.

Conformable base of the Nakimu limestone.

/~~* « 1 • 1 1t1. .1*11 111 * j

Gray, thin-bedded to thick-bedded quartzite,
weathering rusty; with thin interbeds of
phyllite and white quartzite; a few seamlets
of crystalline limestone in the uppermost
quartzite

Conspicuous band of white, homogeneous,

Massive, light gray quartzite, interrupted by
many bands of gray, quartzitic grit and
coarse sandstone and by beds of dark gray,
silicious metargillite; about 1,000 feet
(305 m.) from the top, a thick band of
massive white quartzite

Quartzitic and phyllitic, gray sandstone and
fine conglomerate with metargillite. Near
the middle of this zone, angular fragments
of altered basaltic rock (bombs?) enclosed in
an argillaceous (?)base were found

Altered basaltic lava

Thick-platy to flaggy, sometimes phyllitic, gray
quartzite

5.500
300

3,000

900
50

1,050

1,677
9i

915

274
15

320

Conformable top of Laurie formation.

10,800

3,292

137

East of the divide of the Selkirk range, the Cougar
formation is, on the whole, thin-bedded and more argil-
laceous (originally) than in the section just detailed.
The equivalent strata of the Rocky mountains — the Corral
Creek formation and the lower part of the Hector formation
— are still more argillaceous, consisting of gray, green,
purple, and black metargillites with interbeds of rusty
quartzite. (See p. 172). The rocks of this general horizon
thus become finer-grained, less purely silicious, and more
argillaceous as the section is followed from west to east.
A similar variation characterizes the Rocky Mountain
Geosynclinal rocks at the 49th Parallel section.

The Nakimu limestone is specially notable as being the
most useful horizon-marker in the Selkirk and Purcell
mountains. It is truly protean in lithological features,
but one is seldom at fault in identifying it in the field.
The Caves of Cheops (Caves of Nakimu) have been formed
by solution and by the mechanical erosion of Cougar
creek, as it follows for some distance a subterranean
course in the formation. At that, mc st westerly, outcrop
the formation is a light gray, fine-grained crystalline
limestone. The lock is comparatively homogeneous, but
carries disseminated sericitic mica in many beds. In
the outcrops of the eastern Selkirks and of the Purcell
mountains, the same gray type of limestone is interbedded
with blackish, very carbonaceous limestone and with rusty-
weathering, sandy or pebbly, dolomitic limestone. The
thickness is quite variable — from as much as perhaps 600
feet (183 m.) at the Caves of Cheops to a few feet near
Bea vermouth. These differences are in part original;
in part they seem to be due to squeezing-out during the
uplift of the mountains.

The Nakimu limestone is conformably overlain by the
thick Ross quartzite named from Ross peak, a mountain
opposite Cougar creek at its confluence with the Illecill-
ewaet river. The lower part of this formation is of Pre-
Cambrian age; the upper part is probably to be assigned
to the Lower Cambrian. All these admirably exposed beds
are conformable not only with one another but also with
the definitely Lower Cambrian Sir Donald quartzite above.

In the section between the Caves of Cheops and Rogers
Pass station near the summit of the Selkirks, the Ross
formation is relatively homogeneous, with composition as
here indicated :
35069— 3§A

138

Columnar Section of the Ross Formation

Thickness

Conformable base of Sir Donald quartzite.

Gray, rarely rusty, thick-bedded, compact
quartzite, with interbeds of gray and brown-
ish quartzitic sandstone and grit

Pale rusty-brown silicious phyllite or sericitic
quartzite, carrying in the middle a 15-metre
bed of gray quartzite

Gray quartzite, thick-platy and homogeneous,
weathering gray and rusty; with interbeds
of hard quartzitic grit and sandstone

Conformable top of the Nakimu limestone.

1 ,600

In the grand exposures along the northwestern edge of
Beaver River valley the Ross formation weathers more
uniformly rusty but is still quartzitic; this section shows
an approximate thickness of 5,000 feet (1,524 m.). At
the summit of the Dogtooth mountains, the formation is
more argillaceous, while retaining its deep rusty colour
and numerous bands of fine quartz conglomerate or grit
so characteristic in the Selkirks. It is correlated with the
shaly to sandy beds in the upper part of the Beltian-Hector
formation and in the Lower Cambrian Fairview formation
— both exposed in the Bow River valley of the Rocky
mountains. Here again the geosynclinal rocks in the east
are more argillaceous than those contemporaneously
deposited in the west.

Cambrian System.

At the summit of the Selkirk range the Ross quartzite
passes gradually upwards into the Sir Donald formation.
This is a very homogeneous mass of quartzite, much like

140

the more silicious phase of the Ross but weathering with
a gray, rather than a rusty, surface. On fresh frac-
tures the Sir Donald quartzite varies in the colour from
white through pale gray and greenish-gray to dark gray,
rarely rusty. It is characteristically thick-bedded. Like the
Ross formation it is often feldspathic and is charged with
numerous lenses of quartz-feldspar grit and fine quartz-
feldspar conglomerate. Near the base there is a 53-metre
band of pale-rusty to gray quartz-sericite schist.

Summit of Mt. Tupper from Tupper Crest, showing characteristic habit of the
Sir Donald quartzite. Photograph by Howard Palmer.

The Sir Donald quartzite forms most of the highest
summits of the Selkirk mountains and is terminated above
by the present erosion surface. It has yielded no fossils
but clearly represents the fossiliferous Lake Louise and
St. Piran series of the Rocky mountains. The Lower
Cambrian Mt. Whyte formation of the Rockies may also
be correlated, tentatively, with the upper beds of the Sir
Donald quartzite.

The general correlation of formations in the Selkirks
and Rockies may be stated as follows:

I4i

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o

g
O

ON CO N

m N

fH 00

o ioic

ON o o

fONH

C • o

t3.il

e -i_> c
§ I S o

c
o
Q

UBuqui,B3

n vO cO
ON o o

vO O

o o

o >o

lO CO

CN1

^ o

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N G
rt -

O 0}

142

With the exception of the Sir Donald and upper- Ross
quartzites. Cambrian strata are absent in the railway
section west of the Rocky Mountain trench. The enor-
mous development of the Cambrian in the Rocky mountains
was demonstrated by McConnell and Dawson. More
recent studies by Walcott and Allan have led to its detailed
subdivision, as here summarized.

Columnar Section of the Rocky Mountain Cambrian.

Thickness.

Formation.

Feet.

Metres.

Ottertail limestones

1,725

526

Chancellor shales, etc

4oOO

1,372

Upper

1,375

419

Cambrian

Paget limestones

360

Bosworth limestones, etc

1,855

565

Eldon limestones

2,728

831

Middle

- Stephen limestones, etc

640

196

Cambrian

Cathedral limestones

1.595

486

Mt. Whvte shale, etc

39o

Lower

/ St. Piran quartzitic sandstone

2,705

824

Cambrian

Lake Louise shale

105

vFairview sandstone, grit, etc. .

600

183

18.578

5.663

On pages 17411. will be found Dr. Allan's summary
description of these formations.

Ordoviciax System.

Ordovician strata are represented at the railway section
only within the limits of the Rocky mountains and the
floor of the Rocky Mountain trench. These beds once
extended over the site of the Purcell range and over much

143

of the eastern Selkirks but have there been completely
denuded. It is highly probale that the western half of
the Cordillera was a land surface during the Ordovician.

In our section the system is composed of the Goodsir
shales and the Graptolite shales. Dr. Allan credits
them with respective thicknesses of 6,040 feet (1,841 m.)
and 1,700 feet (518 m.). His account of them appears
on pages 1 79-181.

Silurian System.

The Silurian rocks of the section seem to have had the
same general distribution as the Ordovician shales. To
the younger system belong the Halysites beds, a formation
named by McConnell and described on page 181 by Dr.
Allan, who estimates the thickness of the formation at
1,850 feet (563 m.)

Devonian System.

Sediments of Devonian age in the railway section are
also confined to the Rocky mountains. The Intermediate
limestone, named by McConnell and described by Dr. Allan
on page 181 has a thickness estimated at 1,800 feet
(548 m.) or more. In the Sawback range it is conformably
underlain by the unfossiliferous Sawback formation, 3,700
feet (1,128 m.) thick. This is certainly post-Cambrian
but its exact age cannot now be declared. (See page 1 82 .)

Mississippian System.

The strata formerly mapped as Carboniferous in the
Rocky mountains of our section have recently been shown
by Shimer to be partly Mississippian and partly Pen-
nsylvanian in age.* The former system is represented in
the Lower Banff limestone (thickness, 1,500 feet or 457 m.)
and the overlying Lower Banff shale (thickness, 1 ,200 feet
or 366 m.), both named in McConnell's original report.
[2, p. 17]. Some details concerning these will be found on
page 182.

*H. W. Shimer, Summary Report, Geo. Surv. Can. ioio, p. 147. Since this
passage was written Dr. Shimer has concluded from palaeonto logical evidence that at
least part of the Lower Banff limestone is Devonian.

144

Pennsylvanian System.

In the Rocky mountains of our section the Pennsylva-
nian system includes the Upper Banff limestone, and the
overlying Rocky Mountain quartzite, with estimated or
measured thicknesses of 2,300 feet (701 m.) and 800 feet
(244 m.) respectively. Dr. Allan's account of them is
given on page 183.

Pennsylvanian rocks show yet greater thickness in the
western half of the Cordillera, where they represent the
the oldest Paleozoic strata known in the railway section.
They have been named by Dawson the Cache Creek group,
his own description may be quoted in abstract. Writing
of the group as a whole he says:

"The lower division consists of argillites, generally as
slates or schists, cherty quartzites or hornstones, volcanic
materials with serpentine and interstratified limestones.
The volcanic materials are most abundant in the upper part
of this division, largely constituting it. The minimum
volume of the strata of this division is about 6,500 feet.
The upper division, or Marble Canyon limestones, consists
almost entirely of massive limestones, but with occasional
intercalations of rocks similar to those characterizing the
lower part. Its volume is about 3,000 feet.

"The total thickness of the group in this region would
therefore be about 9,500 feet, and this is regarded as a
minimum. The argillites are generally dark, often black,
and the so-called cherty quartzites are probably often
silicified argillites. The volcanic members are usually
much decomposed diabases or diabase-porphyrites, both
effusive and fragmental, and have frequently been rendered
more or less schistose by pressure ....

"In the southern part of British Columbia, the Cache
Creek group shows some evidences of littoral conditions
toward the west slopes of the Gold [Columbia and adjacent]
ranges, probably indicating the existence of land areas
there." [5, p. 70].

Travelling westward over the railway, the Cache
Creek rocks first appear in a long section east of Kamloops
on the South Thompson river. (See page 231). The group
originally covered all, or almost all, of the western half of
the Cordillera and has been found to have a thickness of
at least 6,800 feet (2,073 m0 m the Chilliwack canyon,
near Vancouver. [11, Part I, p. 514, and Part II, p. 559].

145

Dr. N. L. Bowen's Agassiz series, noted on page 258, is
probably part of the same great geosynclinal.

Permian System.

As yet rocks of Permian age are known only in the
Rocky Mountain portion of the railway section. There
Shimer has shown that the Upper Banff shale is to be so
dated. With a thickness of 1,400 feet (427 m.) it lies
conformably upon the Rocky Mountin quartzite. Dr.
Allan summarizes the character of the formation on page
183.

Triassic System.

No formations referable to the Triassic are known in
the railway section across the Rocky, Purcell, Selkirk, and
Columbia Mountain ranges. On the other hand, Triassic
rocks are extensively developed in the western half of the
Cordillera, where they have had a volume comparable to
that of the Cache Creek phase of the Pennsylvanian.
Dawson proved the lower Mesozoic age of his Nicola group,
which still covers large areas in the Belt of Interior Plateaus.
The greater part of this group is constituted of basic vol-
canic rocks (chiefly basalts and diabases) with thin inter-
beds of limestone carrying Triassic fossils. The upper
members of the group are referred to the lower Jurassic.
Dawson estimated the total thickness at the Thompson
river to be 13,500 feet (4,115 m.), of which at least nine-
tenths represents volcanic rock. On account of the
extraordinary massiveness of the lavas, it has as yet
proved impossible to make a trustworthy columnar section
for the group.

Thick fossiliferous shales of Triassic age have been
found in the Cascade range just south of the railway at
Harrison Mills, 61 miles (98 km.) from Vancouver. The
Boston Bar argillites, occurring between Lytton and Hope,
have recently been shown by Dr. Bowen to be of Mesozoic
age and may also belong to the Triassic.

Jurassic System.

Excepting those noted in the Nicola group, no Jurassic
fossils have been discovered in our section west of the

147

Rocky mountains. In that range itself the rock system
is represented by the Fernie shale, with a thickness of
1,500 feet (457 m.). Its description is briefly given by
Dr. Allan on page 184.

Cretaceous System.

Following the orogenic disturbances near the close of the
Jurassic, sedimentation in our section became restricted
to relatively narrow geosynclines or zones of overlap. A
thick mass of Cretaceous strata was deposited in a down-
warp along the eastern limit of the Cordilleran area. Other
local geosynclinal prisms were developed near the line of
the present Pacific coast. The stratigraphy of each of
these two sedimentary provinces needs separate treatment.

In the eastern Rockies, west of Bankhead, beds lying
conformably on the Jurassic Fernie shale and all of Lower
Cretaceous age, have been subdivided into three formations:
the Lower Ribboned sandstone, the Kootenay Coal measures
and the Upper Ribboned sandstone. Their respective
thicknesses are approximately: 1,000 feet (305 m.), 2,800
feet (853 m.), and 550 feet (168 m.). On page 185 is to
be found Dr. Allan's description of the formations. The
railway section does not give the full thickness of this
geosynclinal, to which Dawson has credited a value of
more than 11,000 feet (3,353 m.).

Six hundred kilometres (370 miles) farther west, Lower
Cretaceous rocks again appear in the section. They cover
two principal areas: one at Ashcroft, the other following
the Fraser valley north and south of Lytton. Both groups
of rocks are doubtless remnants of a single geosynclinal,
once covering part of the Belt of Interior Plateaus as well
as part of the Coast Range region. A still greater remnant
has been mapped at the 49th parallel section under the
name Pasayten series, of which the Lower Cretaceous
members alone have a thickness of about 7,000 metres.

The erosion remnants at Ashcroft and Lytton consist of
highly indurated sandstones, argillites and conglomerates.
"The sandstones are most commonly of greenish-grey
colours, passing on one hand into coarse, distinctly green
rocks, largely composed of arkose materials derived from
the older [Paleozoic and Triassic] greenstones and [late
Jurassic] granites; on the other, into fine-grained blackish
sandstones, which grade down perceptibly into argillites

148

of the same colour." [4, p. 151]. Owing to structural
complication, no attempt at a detailed section of the Cre-
taceous in either of the areas has yet been successful.
Dr. Drysdale estimates the minimum thickness of the
Ashcroft remnant at 5,000 feet (1,524 m.), while Dawson
indicated a value of 7,000 feet to 10,000+ feet (2,133 to
3,048 +m.) for the Fraser valley Cretaceous. A partial
section in the latter area (Jackass Mountain series) is
given by Dr. Bowen on page 258. Mr. Camsell also refers
certain quartz porphyry flows found west of Hope station
to the Lower Cretaceous. (See page 273.)

EOCENE SYSTEM.

In our section rocks of Tertiary age are entirely confined
to the western half of the Cordillera. So far as known,
they have originated in volcanic action or in fresh-water
sedimentation, though it is possible that the Eocene strata
of the Pacific coast are partly marine.

The formations assigned to the Eocene are: the sedi-
mentary Coldwater group ; and the sedimentary Puget
group. These are local formations and their mutual
relations have not been fully determined.

The Coldwater group, named and mapped by Dawson,
is probably younger and includes conglomerate, sandstone,
shale and coal accumulated in the valleys formed during
and after post-Cretaceous mountain-building. Penhal-
low's recent study of the fossil floras contained in these
beds as mapped by Dawson refers at least part of them
to the Eocene proper [6, p. 106]. Dawson estimated the
local maximum thickness of the Coldwater beds to be
about 5,000 feet (1,524 m.)

Like the other Eocene groups, the Puget beds — sand-
stones, conglomerates and shales with thin coal beds — are
in unconformable relation to the Cretaceous. They attain
very great thickness in Puget sound. In the railway
section the group is truncated by the existing erosion
surface; the remnant of the Tertiary sediments on the
lower Fraser has an observed thickness of about 3,000 feet
(914 m.)

OLIGOCENE SYSTEM.

The Belt of Interior Plateaus is widely covered with
lavas mapped by Dawson as the ' Upper Volcanic Group f

149

and referred by him to the Miocene, as then defined for
western stratigraphy [5, p. 80]. Dr. Drysdale is still inclined
to regard the lavas as of lower Miocene age (see page 243),
though recent paleontological and stratigraphical work
by Lambe and Penhallow seems to show that these rocks —
hereafter called the Kamloops Volcanic group — should be
assigned to the Oligocene. The fossils in question, fish
remains and plants, have been found in the Tranquille
beds, a series of local, tuffaceous, partly fresh-water sedi-
ments intercalated near the base of the Kamloops volcanics.

The Tranquille beds are estimated to have a thickness
of 1,000 feet (305 m.) ; the Kamloops lavas, a maximum
thickness of at least 3,000 feet (914 m.), with an original
average thickness probably greater than 2,000 feet (610 m.)

The Kamloops volcanics are the youngest bed-rocks
known in the railway section. Up to the present time no
Miocene or Pliocene sediments have been found there.
Within sight of the railway, at Mission Junction, is the
Pleistocene-Recent volcano, Mt. Baker.

PLEISTOCENE SYSTEM.

The Quaternary formations are briefly noted at various
appropriate places in this guide-book.

GENERAL STRUCTURE.

The sedimentary rocks of our trans-montane section
belong to three geological provinces.

The Beltian and Lower Cambrian strata of the -
Selkirk mountains and their equivalents in the
Rocky mountains, with the conformable formations
of Middle Cambrian to Permian age, together form
a single mass of rocks. In the Selkirks there is
perfect conformity between the Lower Cambrian and
Beltian systems ; in the Rockies their relation is
reported to be that of conformity at some contacts, and
that of moderate unconformity at others. (See page 172).
There is no thorough-going unconformity in this gigantic
series. It is, in fact, best regarded as a single geosyn-
clinal prism of the first order. The maximum thickness
of strata here represented is, perhaps, greater than that of
any other measured group of sediments. With varying

150

strength and complication, including the presence of local
unconformities, this prism is already known to extend from
Colorado to Western Alaska. Throughout the length
of the Cordillera in Canada and Alaska as well as in the
United States proper, the Rocky mountains are almost
wholly composed of the prism; hence this gigantic unit
has been named the Rocky Mountain Geosynclinal. On
its back have been deposited, unconformably, local geosyn-
clinals of late-Mesozoic and of early Tertiary dates.
These have major axes parallel to that of the older, greater
prism and parallel to the general axis of the Cordillera.
The whole, compound assemblage of sediments forms the
Eastern Geosynclinal Belt of the Cordillera.

On the other hand, the chief sedimentary rocks of the
Coastal system of mountains — including the Coast range
of Alaska and British Columbia, the Vancouver range,
the Olympic mountains, the Cascade range, and the Sierra
Nevada of California — are of Carboniferous (Pennsyl-
vanian), Triassic, and Jurassic age. These beds were
deposited in a broad, very long zone of subsidence. The
sedimentation was not continuous; there are local uncon-
formities in the series. Yet, as a whole, this deposition
was long-continued and on a regional scale within the
geographical zone described. Since, moreover, the clastic
strata were deposited in Pacific water and represent
detritus largely from the Eastern Belt, the whole complex
prism may be called the Main Pacific Geosynclinal. After
a late-Jurassic orogenic revolution affecting this entire
prism, local areas of the now deformed zone were down-
warped and received heavy loads of sediment in the form
of Cretaceous and early Tertiary geosynclinal prisms.
These, along with the much greater Main Pacific Geosyn-
clinal, form the Western Geosynclinal Belt of the Cordillera.

Between the two belts, on the line of the Canadian
Pacific Railway, lies the Shuswap Terrane, the third and
last of the major sedimentary provinces. Its rocks are
of Pre-Cambrian (pre-Beltian) age. In our section, the
eastern limit of the terrane is at Albert Canyon on the
western slope of the Selkirks; its western limit is a few
miles below the outlet of Little Shuswap lake, in the Belt
of Interior Plateaus.

Along the railway, the Rocky mountains form a syncli-
norium, broken by numerous faults and by occasional
zones of mashing. The eastern limb of the synclinorium

i5i

is thrust at least n kilometres (7 miles) over somewhat
deformed Cretaceous strata. The western limb terminates
in a master-fault running in the general line of the Rocky
Mountain trench. This fault, with downthrow of at least
5 kilometres (3 miles), is likewise the eastern limit of a
second synclinorium forming the Purcell mountains and
the eastern part of the Selkirks. The western limit of this

Looking south from Mt. Tupperto Mt. MacDonald and Mt. Sir Donald (background),
showing part of the summit syncline of the Selkirks as shown in the Sir Donald
quartzite forming the great escarpment. Photograph by Howard Palmer.

broad flexure is a relatively simple monocline extending
from the summit of the Selkirks to the primary uncon-
formity at Albert Canyon.

Each synclinorium is unsymmetric, with older strata
exposed on the western edge than on the eastern. This is
particularly striking in the Selkirks, where the Shuswap
terrane is exposed on the west, below the basal beds of the
Beltian system, while the Cambrian quartzites appear at
the surface not far west of the fault in the Rocky Mountain
trench. The maximum amount of uplift registered in the
railway section has charactertized the eastern part of the
35069— 4A

Excursion C i.

Drag folds in the Cougar quartzite near head of Cougar creek, Selkirk range.
Cliff shown is about 15 m. in height.

153

Shuswap terrane, where the younger sediments of pre-
Beltian age have Seen eroded away.

While the Shuswap sediments attained the thickness of a
first-class geosynclinal, no clear hint has been forthcoming
as to the geographical source of their clastic material, nor
as to the direction of the major axis of this prism. There
is nothing to show that the subsiding trough had the
Cordilleran elongation which has been so characteristic
of the post-Shuswap geosynclines. In two leading respects
the pre-Beltian terrane contrasts structurally with the
younger geosynclinals.

The Shuswap series is less deformed than any of the
overlying series, up to and including the Triassic. In the
Selkirks and Interior Plateaus the average dip calculated
for the beds of the oldest terrane is no greater than 350,
while the averages for large, typical areas of the Albert
Canyon division and Glacier division of the Selkirk series,
for the Carboniferous, and for the Nicola series, are,
respectively, about 380, 590, 730, and 640. This is true,
though the Shuswap terrane obviously underlay these
younger formations when they were passing through
several orogenic revolutions. Today, the Shuswap rocks
in numerous areas each many square miles in extent are
nearly horizontal, while adjacent Carboniferous strata are
intensely folded. It appears necessary to believe that the
earth-shell which has here transmitted the mountain-
building thrust had a depth of only a few kilometres;
and that this shell was sheared over its basement of
Shuswap rocks.

The second noteworthy feature is the general failure of
the Shuswap strata to show the Cordilleran trend charac-
teristic of all the younger formations. The prevailing
strike of the basement rocks is about N. 700 E., and thus
nearly at right angles to the general Cordilleran strike
in this latitude. Quite locally the older rocks have been
gripped in a post-Carboniferous plication and show Cor-
dilleran strike ; such exceptions do not invalidate the general
rule. One is reminded of the prevailing E. — W. to N. 6o°
E. strikes in the Pre-Cambrian rocks of Lake Superior
and eastward thereof, in the Canadian Shield. Is this
agreement of structural trends in the two Pre-Cambrian
areas fortuitous?

As already stated, the detailed structure of the Shuswap
terrane offers a host of unsolved problems. In general,
35069— 4§A

154

the deformation of the bedded rocks seems to have con-
sisted in warping and normal-faulting, especially the latter.
The extremely abundant sills and other intrusive bodies
have suffered nearly as much deformation as the invaded
sediments.

The Western Geosynclinal Belt is structurally the most
complex of the three principal provinces. All of its bedded
formations, from the Carboniferous to the Cretaceous
inclusive, are more or less intensely folded. The thick
Carboniferous group has been specially affected by close-
folding and mashing, with resulting turmoil in most of the
Carboniferous areas.

Rocks of the Beltian to the Mississippian, inclusive, are
only locally represented in this province, which except for
limited areas was clearly a region of erosion during that long
period. In our section the oldest known Paleozoic strata
are Carboniferous (Pennsylvanian) in date. These lie
unconformably upon the Shuswap terrane. A second
unconformity is well exposed between the Pennsylvanian
limestone and the Triassic near Kamloops. A third
exists at the base of the Lower Cretaceous; a fourth at the
base of the older Tertiary (Eocene?) geosynclinal deposits
of the Strait of Georgia and Puget sound. An unconfor-
mity is registered at the base of the Oligocene in the
Interior Plateaus and it probably corresponds to a defor-
mation of post- Eocene date. A sixth unconformity is,
of course, seen at the contact of the Pleistocene deposits
with older formations.

NOTE ON THE IGNEOUS BODIES.

The sedimentary rocks of the Eastern Belt are, in our
section, very seldom interrupted by igneous masses.
The remarkable Ice River intrusion (see page 185) and the
contemporaneous lavas in the Cougar formation (see page
136) are the only important eruptions observed in the
railway zone between the Great Plains and the heart of the
Selkirk range. On the other hand, the Western Belt
shows not only a much larger number of unconformities,
but also an incomparably greater amount of igneous acti-
vity.

Following the rule illustrated throughout the world, the
downwarping of the western geosynclines has been

156

accompanied by some contemporaneous volcanic action.
Surface lavas of both central-eruption type and fissure-
eruption type are found in the Pennsylvanian, Triassic,
Eocene, and Oligocene downwarps of the Western Belt.
In our section the volcanics of the Triassic and Tertiary
are much thicker than the sediments of their respective
dates. The Western Belt is, in fact, a volcanic province of
the first order, whether considered as to volume of extra-
vasated material, as to persistence of eruptivity in geolo-
gical time, or as to area of country still covered by the
lavas. The great cone of Mt. Baker, south of the railway
at Mission Junction, represents Pleistocene-Recent
vulcanism.

Batholithic intrusions are very rare in the Eastern Belt and
are entirely absent in the railway section. They cut the
Paleozoic strata of the Western Belt on a scale unmatched
elsewhere in the world except, perhaps, in the Pre-Cambrian
terrane of Eastern Canada, Fennoscandia, etc. The com-
posite Coast Range batholith of British Columbia and Alas-
ka is about 1200 miles (1930 km.) in length, with an average
width of nearly 90 miles (144 km.). The railway section
crosses it in the stretch between Lytton and Vancouver.
It is composed of granodiorite and quartz diorite, with
diorite, biotite granite, syenite, and allied types. There
is clear evidence of successive intrusion but it is agreed
that the general date of irruption for the greater part
falls in the period from the latest Jurassic to the early
Cretaceous. In our section the late Jurassic is the pre-
ferred date. Yet it is probable that this batholith, like
those in Washington State and in the Kootenay district
of British Columbia, received large increment or else batho-
lithic replacement in post-Cretaceous time. In the railway
section itself such Tertiary batholiths have not yet been
proved and the earlier date is generally accepted for many
smaller batholiths east of the Fraser river as well as for the
Coast Range body. Some of the little sheared granitic
masses cutting the western part of the Shuswap terrane are
tentatively referred also to the late Jurassic.

These various bodies illustrate again and again the cross-
cutting and apparently bottomless relations of true batho-
liths. The main contacts and the attitude of roof-pendants
are eloquent in favour of the replacement theory of origin
and strongly oppose the "laccolithic" theory. Evidence
on this fundamental matter has been collected by: Clapp

157

in Vancouver Island; by Dawson, Bowen, Camsell, Le Roy,
Bancroft and Daly in the Coast range ; and by Daly in the
Belt of Interior Plateaus. Their conclusions agree with
many recent results of study in the Alaskan and United
States portions of the Western Belt.

GENERAL HISTORY.

The earliest event demonstrated in the rocks of our sect-
tion is the long-continued erosion of a silicious( granitic or
gneissic) land surface older than the Shuswap series. No
actual representation of this ancient mass has been dis-
covered, but its existence is inferred from the abundant
development of clastic, sandy and argillaceous beds of
Shuswap age in south-central British Columbia. This
deposition continued long, though it was often interrupted
by the precipitation of limestone (e.g., Sicamous formation.)
Clastic and chemical sediments together formed a geosyn-
clinal mass several kilometres in thickness. Within it
there is no sign of unconformity. Toward the close of this
epoch of sedimentation and before any notable deformation
of the geosynclihe, basic lavas broke through the earth's
crust and buried the older deposits very deeply (Adams
Lake greenstone).

The lower members of the series were drastically affected
by static metamorphism, whereby sediments and lavas
became converted into true crystalline schists — metargill-
ites, phyllites, and other mica schists, quartz-sericite
schists, calc-schists, chloritic and uralitic schists. Exces-
sive fissility essentially parallel to bedding-planes was thus
imposed upon the Shuswap series. It was then invaded by
granitic magma which sent off-shoots into the easily split
schists, in the form of innumerable sills, laccoliths, and
dykes, on a scale seldom matched. The plutonic invasion
took place by successive stages, so that older intrusions
are cut by younger. As so often the case, the youngest
magmas were aplitic or pegmatitic in habit. This salic
material forms countless small bodies in the Shuswap
terrane. Practically all these intrusions, except the
youngest aplites and pegmatites, were themselves sub-
jected to static metamorphism, converting them into
orthogneisses. The resulting schistosity, generally well
developed, is sensibly parallel to the stratification planes of
the adjacent sediments.

158

These intrusions must have been accompanied by some
deformation of the Shuswap series. In any case, the plut-
onic invasion was followed by erosion which bit deeply
into the new terrane — a process long continued, implying
great uplift above baselevel. The uplift was, however,
not accomplished as an incident of intense folding. The
average dip of the Shuswap rocks is today low. It must
have been lower in pre-Beltian time, for the planes of
schistosity and sill-contacts of the Shuswap are nearly
parallel to the basal beds of the Beltian system at Albert
Canyon and have been upturned to angles of 450 to 550 since
Beltian time. The pre-Beltian deformation may well
have developed a broad geanticline accidented by slightly
tilted fault-blocks. Their average strike possibly corres-
ponded with the present dominant strike of the terrane,
namely, about N. 700 E.

The first sediments formed by the erosion of the Shuswap
terrane have nowhere been identified. A great mass of
it had already been removed before the region about Albert
Canyon was depressed below sea and was covered by the
lowest exposed bed of the Beltian system. That bed was a
little-washed arkose sand, in mineralogical composition
differing but little from the shell of secular weathering on
the Shuswap orthogneiss beneath. It is probable that
this unconformity represents the preliminary erosion of
the Shuswap bedded series at this locality.

With the geanticlinal uplift of the pre-Beltian terrane,
the oldest known structure visibly paralleling the existing
Cordilleran axis was developed. The zone roughly repre-
sented by the Western Geosynclinal Belt now became a
land mass and the zone represented by a large part of the
existing Eastern Belt become an elongated basin of deposit-
ion (largely, if not wholly, marine in our section). The
floor of the basin slowly subsided and upon it the Rocky
Mountain Geosynclinal was accumulated. More or less
continuously, from the beginning of the Beltian to the close
of the Mississippian, this prism increased in thickness;
during the Middle Cambrian it was greatly widened by
marine transgression far to the eastward, if not to the west-
ward, of the initial shore-lines. Detailed study of the
sediments shows that their clastic materials, even as far
east as the Front range of the Rockies, were largely de-
rived from the land on the west, though a small proportion

159

was washed into the geosyncline fron land masses located
in the longitudes of Montana and Wyoming.

In Arizona, Colorado, and elsewhere in the United
States, the early Cambrian was a time of erosion following
local deformation in the Rocky Mountain Geosynclinal
area; and in the late Middle Cambrian a re-submergence,
contemporaneous with the marine transgression elsewhere,
restored conditions of sedimentation in the zone. In
British Columbia and Alberta, however, there appears to
be perfect conformity throughout the Cambrian. Opinions
differ as to the existence of an erosional break at the base
of the Lower Cambrian in the Rockies. Walcott has
announced the existence of an unconformity in the rocks
of the Bow valley but later observations by Di. Allan and
by the present writer indicate that the break at this horizon
must in any case be local and does not represent a long inter-
val of time.

As yet it is impossible to locate the line of maximum
thickness for the geosynclinal. In the railway section
the Beltian and Lower Cambrian strata grow thinner as
they are followed eastward into the Rocky mountains,
where the Middle and Upper Cambrian strata have their
greatest known strength.

Next to the clastic material won from the adjacent
lands, the most abundant constituent of the Rocky Moun-
tain Geosynclinal is carbonate, chiefly limestone with some
true dolomite. All of the pre-Ordovician carbonate-
rock and most of the younger limestone and dolomite
seems to be best explained as chemical precipitates. The
total of the maximum thicknesses recorded for the carbon-
ate rocks is more than 6,000 metres (20,000 feet).

Though contemporaneous vulcanism is recorded in this
great prism at various horizons of the 49th Parallel section
as well as elsewhere in the United States, it has added
very little to the bulk of the geosynclinal at the Canadian
Pacific section. So far as now known, the only occur-
rences of lava are those found in the Beltian Cougar
formation.

In the Pennsylvanian (Carboniferous) period the
geosyncline was enlarged both eastward and westward
on a scale probably surpassing the marine transgression
of the Middle Cambrain. Pennsylvanian sediments,
chiefly limestone, were laid on the prism and in yet greater
thickness limestones, shales, and more silicious beds were

i6o

now deposited in the Western Belt, which for the most
part had so long remained above sea. The exact sources
of supply for this fragmental detritus can not be fully
determined. It is possible that islands of the Shuswap
rocks still remained, and probable that parts of the Rocky
Mountain Geosynclinal were upwarped, so as to surfer
erosion during the Pennsylvanian. We know more de-
finitely that some of the sedimentary matter in these rocks
of the Western Belt was derived from the erosion of
contemporaneous volcanoes. Great eruptions of basalt
and basic andesite were widespread in the Western Belt
during this period.

The Permian period has left no record of rock formation
in the Western Belt but seems to be represented by con-
tinued deposition in the Eastern Belt (Upper Banff shale,
1,400 feet; 427 m. thick).

West of the Shuswap Lakes region the Pennsylvanian
strata were at least locally subjected to moderate defor-
mation, followed by erosion. These events anticipated
the deposition of the Triassic shales and limestones, among
which exceptionally heavy flows and pyroclastic masses
of basalt were erupted. This vulcanism was widespread
in the Western Belt, from Alaska to California. In
British Columbia it took the form of heavy fissure erup-
tions with subordinate central eruptions. Few lava
formations are as massive as the extensive and very thick
basalts of the Xicola group. It is not certain that Jurassic
sediments are represented anywhere in the railway section
of the Western Belt. Hence the history of the Jurassic
period is here obscure. From the analogy of other regions,
particularly California, it is concluded that this part of
the belt was strongly folded during the closing stage of the
Jurassic.

In the Eastern Belt the Paleozoic era was closed by a
broad upwarping, by which the sea was largely withdrawn
from the Rocky Mountain geosyncline. It is probable
that at least the western half of this belt in our section
has been out of water ever since and that conditions of
erosion there prevailed in the early Mesozoic. The
upper Jurassic of the eastern foot-hills is conformable with
the Cretaceous of the Great Plains and, like the latter,
was probably in piedmont relation to the Cordillera
Eastern Belt. The late Jurassic orogeny, so powerful
in the Western Belt, did not seriously deform the Paleozoic

i6i

strata of the Rocky mountains; upon those the Jurassic
and Cretaceous lie with apparent conformity. In the
general absence of Mesozoic sediments in the Middle
ranges of British Columbia, it is a delicate, still unsolved
problem as to how far the western part of the Eastern
Belt was mountain-built during the Jurassic. Perhaps
the information will be found along the new Grand Trunk
Pacific Railway line.

The late Jurassic folding in the Western Belt was
immediately followed by granitic intrusion on a grand
scale, whereby the enormous Coast Range batholith was
outlined, if not largely completed. Many smaller batho-
liths and stocks were simultaneously intruded into the
older rocks of Vancouver island and of the broad tract
between the Coast range and the Selkirks.

From that time to the present both Eastern and Western
belts of the Cordillera have witnessed subaerial erosion.
Near the line of the present Pacific shore and also in the
eastern foot-hill zone of the Rockies, local geosynclinals
of great depth were formed in the Cretaceous, Examples
are: the Pasayten geosynclinal , stretching from west-
central Washington to and beyond the Fraser valley at
North Bend and Lytton; the Queen Charlotte geosyn-
clinal, west of the Coast range; and the Crowsnest geosyn-
clinal of the Eastern Rockies. Sediments of both Lower
and Upper Cretaceous age occur in these local downwarps
of Cordilleran trend.

With the completion of the thick Cretaceous prisms,
the conditions were ripe for renewed mountain-building
and the Laramide revolution deformed most of the Canadian
Cordillera. As in the more limited Jurassic revolution,
the major thrusts were directed from the Pacific side
but they were now, for the first time since the pre-Beltian
period, of pronounced effect at the extreme eastern limit
of the Eastern Cordilleran Belt. All observers agree
that the major deformation of the Rocky Mountain Front
ranges took place at this time. Opinions differ as to the
date of the great overthrust by which those ranges have
advanced outwards, over the Great Plains. Willis has
postulated a mid-Tertiary date for the Lewis thrust at
the International Boundary, but the present writer is
inclined to regard it and the similar thrust in Alberta as
incidents of the Laramide revolution [6, p. 340; and 11,
Part I p. 94].

1 62

Thus, at the dawn of the Tertiary the Cordillera was
developed with full vigour of mountainous relief. Its
volume in British Columbia, measured above sea level,
was then probably at its maximum. Its general history
is henceforth one of erosion coupled with intermittent
vulcanism of great intensity and with diastrophic move-
ments which were of great importance but of an order
less than the revolutionary. In the absence of a wide-
spread sedimentary record in the mountain chain, it is
difficult to state Tertiary events in an orderly, quantita-
tive way. Long chapters in the Tertiary history can
only be written in the future, after modern physiographic
methods have been applied in the as yet unmapped portions
of British Columbia.

In the Canadian Pacific section no marine sediments of
Tertiary age have been definitely reported. The Eocene
geosynclinal of Puget sound was doubtless continued into
the region of the Strait of Georgia and lower Fraser valley;
but this irregular prism represents an intermont basin, in
which much of the deposition was subaerial or in fresh or
brackish water. There resulted one of the thick stratified
masses necessarily developed in Eocene basins from the
wasting of the new, vigorous mountain chain. It is prob-
able that the Belt of Interior Plateaus saw, in this period,
a moderate amount of local volcanic action, paralleling
the greater Eocene eruptions of Central Washington and
of the Coast region. The eastern Cordilleran Belt carries
no rocks of this period, which was apparently occupied
throughout by erosive activity.

The Oligocene continued this erosion across the entire
chain, but was marked in the Western Belt by long-contin-
ued emission of basalts, chiefly of the fissure-eruption
type. This vulcanism involved much disturbance of
drainage system. Local basins were formed and became
filled with gravels, sands and muds, bearing fresh-water
fossils (Tranquille group).

The Western Belt became affected by moderate orogenic
movement, whereby the Oligocene lavas and sediments
were locally upturned, sometimes to vertical position.
This deformation is not yet accurately dated, but may prove
to be of late Oligocene date. Though the local upturning
was so pronounced, the Tertiary lavas of British Columbia
were, in general, little disturbed from their original, flat
attitudes, and it is reasonable to suppose that similarly

1 63

large surfaces underlain by non-volcanic rocks were not
greatly deformed.

The Miocene was a time of general erosion across the
entire Cordillera at our section.

The Cordilleran topography at the beginning of the
Pliocene was evidently highly complex in origin and of

Diagram drawn to scale, showing development of columnar jointing in Tertiary
basaltic flow near Ducks station. The gently dipping limb of the syncline is
composed of regular columns of great size. The upturned limb is composed of
four sets of regular but much smaller columns. The latter seem to have developed
through orogenic stresses superposed on original cooling stresses.

great variation in age. Large areas had been undergoing
erosion since the closing days of the Paleozoic; other areas,
since the Triassic; others, since the late-Jurassic revolu-
tion; still others, since the Laramide revolution; while
practically the whole Cordillera, except the part covered
by Tertiary volcanics or local pockets of earlier Tertiary
sediments, was being eroded during Eocene, Oligocene and
Miocene times. We may well believe that, in places, the
unceasing erosion of the whole (pre-Pliocene) Tertiary era,
in spite of post-Oligocene deformation, had virtually pro-
duced local or widespread peneplains. Elsewhere moun-

1 64

tain torsos must have been the rule, except on the lava
plains. In short, the early Pliocene Cordillera was a torso
landscape, locally veneered with, and smoothed by, basaltic
floods. It was this topographic composite, already close
to sea level, which early Pliocene erosion somewhat further
reduced toward a base level of fairly constant position.

Toward the close of the Pliocene all or nearly all of the
Canadian Cordillera seems to have been elevated, to heights
varying considerably, but reaching maxima of from 2,000
to 4,000 feet (610 to 1,220 m.). The streams so rejuven-
ated have had time to sink deep valleys in all three of the
great Cordilleran Belts. This two-cycle topography is
specially well illustrated in the Belt of Interior Plateaus,
but it can be discerned in the Rocky Mountain trench, in the
region around Revelstoke, and elsewhere along the railway
section. The plateaus of the interior have been thus iso-
lated from one another. In part, they represent dissected
lava tables; in part, dissected local peneplains of pre-
Miocene date; in part, dissected mountain torsos, reduced
during the early Tertiary and the Mesozoic. There is no
evidence that a general peneplain was developed over this
part of the Cordillera at any time ; nor is it proved that the
upland facets of the Interior Plateaus were due to general
peneplanation of that broad belt in late Miocene and early
Pliocene time. A superficial study of the Interior Plateaus
might lead to that conclusion; in reality, the upland relief
has been conditioned by several pre-Miocene erosion
cycles.

The Pleistocene glaciers gradually overwhelmed a mature
to sub-mature topography. Their work represents a
chapter of Cordilleran history already sketched; some of
its details will be noted in annotations on the route to be
followed by the excursionists. The recent changes in the
late Glacial landscape are relatively slight and for the
most part are too obvious to need formal statement in
this place.

SPECIALLY NOTEWORTHY FEATURES.

In the midst of a multitude of problems and ascertained
facts, certain aspects of the Cordilleran geology are worthy
of special attention. Some of these are here listed for the
convenience of the excursionists.

165

1. The great development of Cambrian sediments; their
extraordinary richness in fossiliferous horizons and in new
species and genera; the perfection with which some of this
fauna has been preserved.

2. The unusually complete exposures and vast thickness
of the Beltian system of rocks conformably underlying the
Lower Cambrian.

3. Illustration of geosynclinal prisms of various ages.

4. The large area of pre-Beltian ("Archean") forma-
tions, including sediments, volcanics and orthogneisses.

5. Specially clear illustration of the efficiency of static
metamorphism (Shuswap terrane and Beltian system).

6. The wide extent and great thickness of basic vol-
canics referred to the Triassic and to the mid-Tertiary.

7. The section through the Coast Range batholith,
probably the most widely exposed intrusive mass of post-
"Archean" date.

8. The evidences of a chemical origin for limestones and
dolomites thousands of metres in thickness.

9. The opportunity of passing through the Rocky
Mountain Geosynclinal into the terrane which furnished
most of its clastic materials.

10. A view of the important unconformity at the base
of the Rocky Mountain Geosynclinal.

11. The sections through the Rocky Mountain and
Purcell trenches, two of the more remarkable depressions
in the North American Cordillera.

12. The nature of the railway section as favourable to
the discovery of field facts showing the relative shallow-
ness of the earth-shell involved in orogenic folding.

BIBLIOGRAPHIC NOTE.

The most comprehensive guides to the geological litera-
ture dealing with the railway section of the Cordillera
are: —

General Index to the Reports of Progress, 1863 to
1884, Geological Survey of Canada; compiled by D. B.
Dowling, Ottawa, 1900.

General Index to Reports, 1 885-1 906, Geological
Survey of Canada ; compiled by F. J. Nicolas, Ottawa, 1901.

Summary Reports of the Director, Geological Survey
of Canada, 1907 to 191 2, inclusive.

1 66

Indexes to Xorth American Geology; Bulletins
No. 127, 188, 189, 301, 372, 409, and 444 of the United
States Geological Survey.

In these most of the important publications will be found
under the names — G. M. Dawson, McConnell, McEvoy,
Camsell. Walcott, Allan, and Dowling.

Especially to Dawson, the master in reconnaissance,
geology owes the broad outlines already fixed for the
Canadian Cordillera. A useful summary of its geology
with leading references, is Dawson's 'Geological Record
of the Rocky Mountain Region in Canada, ' published
in the Bulletin of the Geological Society of America,
Vol. 12, 1 90 1, pp. 57-92. His report on the Area of the
Kamloops Map-sheet (427 pages) in Volume 7 of the
Annual Reports of the Geological Survey of Canada
is the most detailed work yet published on any large part
of the railway section. In Volume 53 of the Smithsonian
Miscellaneous Collections (1908), will be found C. D.
Walcott's principal writings on the Cambrian and pre-
Cambrian geology of the Rocky mountains in Canada.

The more important maps referring to the section are : —

Reconnaissance map of a portion of the Rocky
Mountains between latitudes 490 and 510 30'; by G. M.
Dawson, Geol. Survey of Canada, 1886.

Shuswap sheet; by G. M. Dawson, Geol. Survey of
Canada, 1898 (not issued).

Kamloops sheet; by G. M. Dawson, Geol. Survey of
Canada, 1895.

Geological map of the Dominion of Canada; Geol.
Survey of Canada, 1901.

The references in the text of the Cordilleran portion
of the guide book are to the following publications: —

1. Dawson, G.M.. . .Geol. Surv. Can., Rep. of Progress,

1877-78.

2. McConnell, R. G.Geol. Surv. Can., Ann. Report

Vol. II, Part D, 1886.

3. Dawson, G. M ... Bull. Geol. Soc. America, Vol. 2,

1891.

4. Dawson, G. M ... Geol. Surv. Can., Ann. Report,

Vol. VII, Part B, 1894.

5. Dawson, G. M. . .Bull. Geol. Soc. America, Vol. XII,

1 901.

6. Willis, B Bull. Geol. Soc. America, Vol. XIII,

1902.

167

7. Walcott, C. D. ...Smithsonian Misc. Coll., Vol. 53,

1908.

8. Penhallow, D. P.Geol. Surv. Can., Report on the

Tertiary Plants of British Columbia,
1908.

9. Shimer, H.W Geol. Surv. Can., Summary Report

1910, Lake Minnewanka section.

10. Walcott, CD Smithsonian Misc. Coll.: Vol.57,

Nos. 2, 3, 5, 6, 8; 1911-12.

11. Daly, R. A Geology of the North American

Cordillera at the Forty-ninth Par-
allel, Geol. Surv. Can., Memoir No.
38.

ROCKY MOUNTAINS (Bankhead to Golden).

John A. Allan.
STRATIGRAPHY.

COLUMNAR SECTION.

In the section across the Rocky mountains, between
the Cascade trough near Banff to Golden and the Columbia
valley, all the geological systems from the Pre-Cambrian
to the Cretaceous inclusive, except the Triassic, are repre-
sented.

As shown in the tabulated section given below, the
stratified rocks aggregate more than 52,628 feet (16,040 m.)
in thickness. The thin-bedded strata, mostly shales,
make up 23,730 feet (7,235 m.) ; the limestones, 20,528
feet (6,255 m.) ; the quartzites and sandstones, 8,370
feet (2,550 m.).

The relation between the Silurian and the Devonian
systems is not shown in this area, because the Cambrian,
Ordovician and Silurian formations are exposed mainly
on the western slope of the Rocky mountains, while the
remaining systems are exposed wholly on the eastern
side of the Continental watershed.
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1 69

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172

Resume of Section.

Feet.

Metres.

Cretaceous

Jurassic

Permian

Carboniferous. . . .

Devonian

Devonian (?)

Silurian

Ordovician

Upper Cambrian.
Middle Cambrian
Lower Cambrian .
Pre-Cambrian. . . .

4-350+

1,500+

1 .400+

5.800+

1,800+

3wOO+

1,850 +

7.740+

9.8I5 +

4.963

3.800+

5.9IO+

427
1,768

548
1,127

563
2,360
2.992
1. 513
1,158
1,802

1,326

457

Total

52, 628+. 16, 041 +

PRE— CAMBRIAN.

The Pre-Cambrian series is distributed along the floor
and sides of Bow river valley from the base of Castle
mountain, where it becomes faulted off against the younger
Paleozoic rocks, to the head waters of the Bow river.

The contact between the Pre-Cambrian and the Cam-
brian is seldom exposed. It was examined at three locali-
ties. At one exposure in Bath Creek valley, near the
summit of the Rocky mountains, the contact is a conform-
able one, while in two other localities in which the
contact was exposed, there is a noticeable unconformity
between the beds of the two systems. In one case the
Pre-Cambrian shales were dipping 31 degrees S. 550 W.,
and the Lower Cambrian quartzites had a dip of 35 degrees

The rocks in the Pre-Cambrian series, with the three
lowest formations of the lower Cambrian, were formerly
called the 4 Bow River Group' by McConnell [2, p. 29].

Corral Creek Formation. — This formation includes
the lowest beds exposed in the Rocky mountains, along
this section. This series consists of gray sandstone under-
lain by a coarser quartzitic sandstone, with an arkose-like
conglomerate at the base. The lowest beds are exposed
in a railway cut two miles (3,249-2 m.) east of Laggan
station. This rock is made up of small pebbles and
grains of quartz, and angular crystals of white and pink
feldspar. The cement is made up of finer material of

S. 5

0 \Y.

Excursion C i.

Contact of the Pre-Cambrian shales (Hector) and the Lower Cambrian
quartzites. Exposed in Bath creek west of Laggan.

174

the same composition. The nature of this rock suggests
shallow- water or near-shore conditions of origin.

Hector Formation. The beds in this formation consist
of gray, purplish, and greenish shale interbedded with
bands of conglomerate 15 m. to 75 m. thick. The best
exposure is in the Bow range east of Storm mountain,
where the formation has a minimum thickness of 4,590
feet (1,399 m-)- It thins out towards the northwest; in
Mt. Temple, Walcott measured over 2,150 feet (655 m.),
and at Fort mountain towards the head of Corral creek
he obtained a section 1,302 feet (397 m.) thick.

From one layer of shale (50 cm. thick), outcropping on
the eastern base of Storm mountain and about 16 metres
from the top of the series the writer collected fossil remains
of a brachiopod-like shell about one-eighth of an inch in
diameter. This is the only locality in which fossil remains
have yet been found.

CAMBRIAN.

The Cambrian series is complete in this section with
both lower and upper contacts exposed. There is a total
thickness of over 18,578 feet (5,663 m.). This represents
one of the thickest Cambrian sections yet measured in
the world. It essentially consists of 3,800 feet (1,159 m-)
of siliceous beds, principally quartzitic sandstone; 10,275
feet (3,132 m.) of calcareous and dolomitic limestone, and
4,500 feet (1,371 m.) of shale, much of which is calcareous.
The various divisions of the Cambrian series have been
made on paleontological and lithological evidence. The
formations in the Lower and Middle Cambrian and the
first three in the Upper Cambrian were named and meas-
ured by Walcott, [7, p. 204]; the remaining two formations
were named and measured by the writer.

LOWER CAMBRIAN.

Fairview Formation. — The Fairview formation con-
sists of brown and white quartzitic sandstone. Locally
there is a basal conglomerate on the Pre-Cambrian
shales; it consists of rounded pebbles of white quartz, up to
7 cm. in diameter, in a cement of quartz, feldspar and mica.
The basal rock is more frequently a coarse sandstone
with rounded and angular grains of quartz and feldspar,

175

5 to 15 mm. in diameter. Some of the quartz grains have
a glassy, almost opalescent colour.

Lake Louise Formation. — As the name indicates,
these beds are best exposed at Lake Louise. The formation
has a total thickness of 105 feet (32 m.) and consists of a
ferruginous siliceous shale. It weathers more readily
than the beds below or above, so that the slopes are more
gradual.

Mt. Temple, showing a complete Lower and Middle Cambrian section capped by Upper
Cambrian, and underlain by Pre-Cambrian shales (covered by talus).

St. Piran Formation. — This formation consists of
massive-bedded, ferruginous, quartzitic sandstone, with a
total measured thickness of 2,705 feet (824 m.). These
beds form steep escarpments wherever they are exposed.
On the west side of Mt. Victoria the cliffs composed of
these beds are over 2,500 feet high. The brown color
of the rock is due to smoky quartz and small particles of
mica in the cement.

Mt. Whyte Formation. — In sharp contrast with the
underlying massive quartzites, there is a thin series of
siliceous and calcareous shales grouped as the Mt. Whyte
formation. These shales are less resistant than the quart-
zite and form gradual slopes. Some of the layers contain
numerous annelid borings and trails.

1 76

MIDDLE CAMBRIAN.

Cathedral Formation. — This formation consists of
massive and thin bedded dolomitic limestone, which on
the weathered surface becomes buff and gray. The more
massive beds are arenaceous in their composition. It
is on this formation that the Monarch mine in Mt. Stephen
is situated, and other small mineral prospects in the
Kicking Horse valley.

Castle Mountain, showing Cathedral limestone in the lower cliffs; Stephen formation
in the talus covered slope; and the Eldon formation in the upper cliffs.
(All Middle Cambrian).

Some of the limestone has become metamorphosed into
marble. One of the best exposures of this rock is in
Cathedral mountain, four miles (6-4 km.) east of Field.

Stephen Formation. — Although this formation is
only 640 feet (196 m.) thick, yet it is quite important for
the number and variety of fossils which it contains. It
consists of shaly limestone and calcareous shale. These
beds include the 'Ogygopsis shale' in Mt. Stephen, and
the 'Burgess shale' in Mt. Field, on the opposite side of
the valley. The former includes the widely known trilo-
bite-bearing 'fossil bed,' while the latter includes the
new 'fossil bed,' discovered by Walcott in 1910. From
this bed he has obtained an extensive variety of Middle
Cambrian organisms. Coelenterata, Annulata, Echinoder-

Excursion C i.

Fossil bed in "Burgess shale" on Mt. Field, showing character of the shale, method
of quarrying for fossils, and temporary camp of C. D. Walcott.

1 78

mata and certain Arthropoda are abundantly represented
[10].

Eldon Formation. — This formation has a thickness
of 2,728 feet (831 m.) where it was measured in Castle
mountain. It consists essentially of massive-bedded,
arenaceous limestones, which form steep castellated crags
on the erosion surface, thus making the formation readily
recognizable wherever exposed. It is this formation
which forms the steep escarpment about the upper part
of Castle mountain.

The Mitre and Death Trap (pass) to the right. The cliffs on the right are of Middle
Cambrian limestone in Mt. Lefroy. A typical bergschrund is shown around
this portion of the Lefroy glacier.

UPPER CAMBRIAN.

Bosworth Formation. — This formation is exposed in
the mountain of the same name on the Continental
Divide. It consists largely of thin-bedded limestone
with a few more thick-bedded layers, interbedded with
siliceous and arenaceous shale. One band of shale makes
a good horizon-marker because it weathers greenish,
yellowish, deep red, and purplish.

Paget Formation. — A band of grayish oolitic lime-
stone, typically exposed in Paget peak, on the west slope
of Mt. Bosworth, has been placed in this formation.
These beds can not be readily distinguished from the
underlying limestone.

179

Sherbrooke Formation. — Arenaceous limestone at
the base of this formation is overlain by thin-bedded
limestone, including some oolitic and shaly layers. This
formation includes the highest beds exposed in the Bow
Range in the vicinity of Hector Pass.

The remaining Cambrian formations, the Ordovician,
and the Silurian are all exposed in the western portion of
the section between the Bow range and Columbia
valley.

Chancellor Formation. — This formation consists essen-
tially of shales which weather reddish, yellowish, fawn or
gray. The uppermost 2,500 feet (762 m.) are gray met-
argillites, well cleaved along the bedding planes, and
weathering reddish and yellowish. These shales become
much more highly cleaved towards the base of the forma-
tion, so that the lowermost, 2,000 feet (610 m.) thick,
consist chiefly of phyllites and slates, with argillites and
a few interbedded layers of shaly limestone. The fer-
ruginous content in all the beds is high, so that the weather-
ed surface is usually reddish or yellowish. This series
floors Ottertail valley, underlies the Ottertail range, and
makes up a large part of the Van Home range.

Ottertail Limestone. — This formation consists almost
entirely of blue limestone, massive towards the top and
rather thin-bedded towards the base. It has a thickness
of over 1,725 feet (526 m.) in the Ottertail range, where
it is well exposed in an almost perpendicular escarpment
along the east side of the range. The cliff-forming char-
acter of this formation marks it off very sharply from the
shale formations below and above.

This limestone represents the highest series in the
Cambrian in this portion of the Rocky mountians.

ORDOVICIAN.

Goodsir Shales. — This formation is best exposed in
Mt. Goodsir, where it has a measured and estimated
thickness of over 6,040 feet (1,841 m.). It lies conformably
on the Ottertail limestone and consists at the base of
almost 3,000 feet (914 m.) of alternating hard and soft
bands of argillaceous, calcareous, and siliceous shale,
which weather light yellowish, gray and buff.

The upper part of the formation consists of banded
cherts, cherty limestones and dolomites, thin-bedded and

i8o

very dense, so that they weather into compact angular
fragments. The beds in this series become very highly
sheared in the Beaverfoot valley and the range to the
west.

On both paleontologic and lithologic evidence the
boundary between the Cambrian and the Ordovician in
this district is placed at the top of the Ottertail limestone
and at the base of the Goodsir shale.

Cambrian-Ordovician contact in Mt. Goodsir. The gray rock is the Ottertail lime-
limestone, overlain by the dark-colored Goodsir shales.

Fossils were found near the base of the Goodsir forma-
tion at several localities, and have been determined by
Walcott. The following new species have been identified
from this series. : —

Obolus mollisonensis.
Lingulella? allani.
Lingulella moosensis.
Ceratopyge canadensis.

The presence of the Ceratopyge fauna places this forma-
tion at the base of the Ordovician, corresponding to the
horizon of the Ceratopyge shale in Sweden.

The sedimentary series from Mt. Whyte to Goodsir,
inclusive, were included by McConnell in his Castle
Mountain group.

i8i

Graptolite Shales. — These beds have been so named
by McConnell on account of the richness of certain layers
in graptolites. The presence of this fauna determines
the age of the formation as Ordovician.

The Graptolite shales consist of black, carbonaceous,
and brown, fissile shale at the top, underlain by gray
shales which grade into the underlying Goodsir formation.

The thickness of the formation varies and the lower
contact is ill-defined, but a thickness of at least 1,700
feet (518 m.) is represented. These shales occur as two
infolded bands in the Beaverfoot range.

SILURIAN.

Halysites Beds. — The Halysites beds consist chiefly
of dolomitic limestone and white quartzite. This forma-
tion lies conformably upon the Graptolite beds. The
character of the rock sharply distinguishes it from the
older strata. The formation is terminated above by a fault
contact or by an erosion surface. A measured section gave
1 ,850 feet (563 m.). The white quartzite is over 900 feet thick
(274 m.). It is infolded with the graptolite beds in the
Beaverfoot range. Some of the beds of dolomitic
limestone are highly fossiliferous ; corals are most abundant,
but crinoids, brachiopods, and gastropods are also present.

This is the youngest formation exposed to the west
of the Continental Divide, along this section of the Rocky
mountains.

DEVONIAN.

Intermediate Limestone. — This formation consists
of thin-bedded limestones, alternating with harder layers
of gray dolomitic and siliceous limestone, which on the
weathered surface becomes banded. In the Sawback,
Vermilion Lake and Cascade ranges it is exposed, being
repeated by reversed faulting.

The thermal sulphur springs at Banff occur in the
Intermediate limestone. The rock is high in sulphur,
derived by the decomposition of pyrite which the lime-
stone contains; a strong odor of sulphide of hydrogen
is given off when the rock is struck with a hammer.

Some of the beds are highly fossiliferous. Zaphrentis
and brachiopods are the most abundant forms present.

1 82

The upper limit of this formation is not clearly defined
as it is transitional into the Lower Banff shale.

Sawback Formation. — Underlying and conformable
with the Intermediate limestone is a series of massive and
thin-bedded, dolomitic limestone and shale, which Mc-
Connell has placed in the Cambrian. These form a
wedge-shaped band in the Sawback range and lie between
Mt. Hole-in-the-wall and Mt. Edith, with a broader
exposure along the north side of the Bow valley. It has
been possible to measure and estimate a thickness of
about 3,700 feet (1,128 m.) but the actual thickness is
believed to be much greater. Fossils have not yet been
found in this series. Since they differ lithologically
from the Cambrian beds in Castle mountain, which are
largely Middle Cambrian, and from the Cambrian in the
Bow range and to the west of this range, it is proposed
to call this series Sawback limestone. The age of the
formation is still in doubt but it is older than the Inter-
mediate limestone, which is definitely known to be Devon-
ian in age. These beds are lithologically closely related
to some of the Silurian beds in the Beaverfoot range to the
west.

MISSISSIPPIAN.

Lower Banff Limestone.* — This formation grades
into the Devonian limestone below, so that it is not possible
always to draw a sharp dividing line between these two
formations. It is quite clearly defined on its upper con-
tact, as the overlying formation is a shale. The beds
consist of massive-bedded, gray limestone which forms
steep escarpments wherever exposed on the slopes of a
mountain.

This limestone forms the eastern cliffs of Cascade moun-
tain, and Mt. Rundle; and the steeper eastern slopes of
Sulphur mountain. Some beds are fossiliferous, and the
formation is characterized by numerous fossil-like dolomitic
segregations. Many of these resemble certain types of
bryozoan remains.

Lower Banff Shale. — There are about 1,200 feet
(366 m.) of shale included in this formation. These
shales are black to dark gray in colour and weather brown.

*Since Dr. Allan sent his MS. to press, Dr. H. W. Shimer has found that the fossils
recently collected in this limestone show it to be largely if not wholly of Devonian age.

183

They are usually calcareous in composition, but certain
layers are argillaceous and arenaceous. The lower contact
of this series is sharply denned but at the top of the series
the beds change to a shaly limestone difficult to distinguish
from the overlying limestone. The shales weather out
more easily than the limestone, so that a depression is
always formed where these shales cut across a ridge. A
leading fossil is Spirifer centronatus.

Pennsylvanian.

Upper Banff Limestone. — There are over 2,300 feet
(701 m.) of beds included in this formation, which is well
exposed in Sawback and Cascade ranges. The series is
shaly at the bottom, but more massive towards the top.
Cherty lenses and cherty shale interbedded with the
lower shaly limestone help to distinguish this formation
from the shales below. Fossils e.g., Spirifer rockymon-
tanus, are quite abundant throughout the lower beds in
this series.

Rocky Mountain Quartzite. — This quartzite lies
directly on the Upper Banff limestone. It represents a
very sudden shallowing of the water, which, however,
was not rendered muddy. The section in the Sawback
range gave 800 feet (244 m.) as a maximum thickness.
There is a rapid thickening of this formation to the east
so that at Lake Minnewanka, 12 miles (19 km.) to the
east, there are 1,600 feet of quartzite exposed. Certain
portions of the formation are quite fossiliferous. These
fossils e.g., Euphemus carbonarius, can most readily be
found on the weathered surface.

This is the uppermost formation in the Carboniferous.
The lower two formations have been grouped as Mississip-
pian in age, while the upper two correspond to the Penn-
sylvanian. [9, p. 147].

PERMIAN.

Upper Banff Shale. — This formation lies conformably
upon the quartzite and consists of a series of brown,
calcareous and arenaceous, often sun-cracked shales
interbedded with thin layers of sandstone. The shales
weather out more easily than the underlying formations,
forming valleys such as those between the Cascade, Ver-
milion Lake, and Sawback ranges. More than 1,400 feet
35069— 6a

1 84

(427 m.) of strata are represented in this section, but it is
difficult to get an accurate measurement on account of
the foldings and contortions within the beds. A leading
fossil is Schizodns.

A typical view of the Upper Banff shale, exposed in Spray valley at Banff.

JURASSIC.

Fernie Shale. — No sharp line can be drawn between
the Upper Banff and Fernie shales, except where fossils
are found. The Fernie formation consists of black and
dark brown, siliceous, very thinly laminated shales which
break up into small fragments on the weathered surface.
West of Banff it has a limited distribution, lying on the
Upper Banff shale. East of Banff and on the north side
of the Cascade trough, it forms a band about 1,500 feet
(457 m.) thick. The Fernie shale was examined near
Exshaw 6 miles (9-6 km.) east of the Gap. A certain
layer was found to contain clay concretions of which the
largest was 35 cm. in diameter. Another layer, 15 cm.
thick, contained numerous bone fragments. One large
reptile-like jaw-bone is 22 cm. long. There are many
smaller fragments of bone and teeth. Ammonites are
very common in the Fernie shale.

185

CRETACEOUS.

Lower Ribboned Sandstone. — The Cretaceous beds
are exposed along the eastern base of Cascade mountain.
The Lower Ribboned sandstone consists of alternating
bands of brown-weathering sandstone and shale. This
formation follows the bottom of the Cascade trough and
is exposed on the road between Bankhead and the west
end of Lake Minnewanka. The beds are here about
1,000 feet (305 m.) thick.

Kootenay Coal Measures. — This formation consists
of 2,800 +feet (853 +m.) of sandstone and shale enclosing
several workable seams of coal. There are fourteen seams
exposed at Bankhead, where the coal is being mined, and
nearly twice as many have been found at Canmore down
the Cascade trough. The coal is bituminous and anthra-
citic. Several of these seams are being mined at Canmore.
The coal measures are well defined between two massive
sandstone bands which form roof and floor.

Upper Ribboned Sandstone. — This formation con-
sists of thin-bedded sandstones and shales. It is exposed
at the eastern base of Cascade mountain. The beds are
wedged between the coal measures below, and a thrust
plane above. Some of the uppermost Cretaceous beds
were planed away when the older beds were thrust
over them. There are about 550 feet (168 m.)
of beds exposed in Cascade mountain, but this formation
becomes thicker where it is exposed to the northwest and
southeast of this section.

POST-CRETACEOUS .

Igneous Complex. — The only igneous rock in the
Rocky Mountain section is represented by the Ice River
intrusive complex, which has the form of an asymmetrical
laccolith with a stock-like conduit. It has an area of
about 12 square miles (31 sq. km.).

The rocks of the complex are all alkaline in composi-
tion, ranging from nephelite syenite and sodalite syenite
through urtites and ijolites, to a jacupirangite or alkaline
pyroxenite. These diverse types represent a complete
petrographic series with intermediate facies.

The age of the intrusion is believed to be post-Creta-
ceous as determined by structural and correlation evidence.

35069— 6|a

1 86

PLEISTOCENE AND RECENT.

The unconsolidated material is represented by three
types of deposits as shown in the section. The fluviatile
and lacustrine deposits appear in terraces about the sides
of the larger valleys, while the former also floors the
broad flood plains of the main streams, such as the Bow,
the Kicking Horse, the Beaverfoot and the Yoho.

Glacial till veneers the more gradual slopes of the
various ranges, to an elevation at least 9,000 feet (2,743 m.)
above sea-level.

ANNOTATED GUIDE.
(Bankhead to Golden).

John A. Allan.

Miles and
Kilometres.

79-5 m. Bankhead — Alt. 4,510 ft. (1,375 m-)-
127-2 km. This station lies to the western edge of the
from Cascade coal basin described by Dowling [1].
Calgary. About one mile east of this siding the railway
leaves the bottom of Cascade valley and,
turning at 90 degrees to the southwest, passes
between Cascade mountain on the north, and
Tunnel mountain on the south. This was at
one time the course of Bow river, but the channel
was obstructed by the gravels brought down
by Forty Mile creek, as well as by the moraine
left by the continental ice sheet, so that now
the Bow passes through this range between
Tunnel mounta'n and Mt. Rundle.

The structure of the beds in Cascade moun-
tain is well shown in the cliff to the right of the
railway. The beds are steeply dipping to the
west and terminate in a precipitous cliff on
the east. The cliffs at the base are Intermediate
limestone (Devonian), overlain by Lower Banff
limestone (Lower Carboniferous). The Lower
Banff shale above (also Lower Carboniferous)
weathers into talus-covered slopes. The moun-
tain is capped by Upper Banff limestone and

1 87

Rocky Mountain quartzite (Upper Carboni-
ferous). An overthrust fault-line scarp defines
the steep eastern face of this mountain;
the Devonian limestones are thrust over the
Cretaceous coal measures. This fault-line de-
fines the southwest side of Cascade valley. It
is exposed in the base of the Three Sisters,
and extends to the southeast along the eastern
face of the Livingstone range at the Crowsnest
Pass, and into Montana, where it is known as
the "Lewis thrust." It has not been possible
to measure the actual amount of displacement,
but there is a vertical throw of about three
miles (4-8 km.) in Cascade mountain. Mc-
Connell [2] has estimated that the front ranges
of the Rocky mountains have been thrust
about seven miles (11 -2 km.) over the plains
to the east, but it it not possible to measure
the horizontal displacement in the Cascade
Mountain thrust fault.

A spur runs from Bankhead station to the
Bankhead coal mines, about two miles (3 • 2 km.)
to the northeast. These mines are owned and
operated by the Canadian Pacific Railway
Company. They are situated in the Kootenay
coal measures which are Lower Cretaceous in
age. The coal is bituminous and semi-anthra-
cite. The plant is well equipped with a large
breaker and a briquetting mill.

Between the coal mines and Lake Minne-
wanka a section along Cascade river exposes
Cretaceous, Jurassic, Permian and Upper Car-
boniferous beds. This section has been studied
in detail by H. W. Shimer [3]. Fossils are
abundant, expecially in the Rocky Mountain
quartzite. For a portion of this distance the
driveway follows along the top of a morainal
ridge. In Pre-Pleistocene time Cascade river
drained out by Lake Minnewanka and Devil's
Gap to the plains, but in recent time it has cut
through the thick morainal detritus and has
joined Bow river four miles (6-4 km.) east of
Bankhead station.

1 88

Miles and
Kilometres.

82 m. Banff — Alt. 4,521 ft. (1379 m). This is the
131 -2 km. gateway to the Rocky Mountain National
Park. This reservation covers 5,732 square
miles (14,330 sq. km.), and contains many
features of interest. Some of those to be
visited are the hot sulphur springs, sulphur
caves, Sulphur Mountain observation station,
and the buffalo paddock. Looking west from
the station are seen the snow-capped peaks
of the Bourgeau range, ten miles (16 -i km),
distant. The town lies west of Tunnel
mountain. On the north side of the valley
are Cascade mountain and a subsidiary
ridge, Stoney Squaw mountain, in wrhich
is shown the eroded end of an asymmetrical
anticlinal fold.

A few yards to the west of the station Bow
river turns sharply to the southeast, and
after passing the town and cascading over
a very picturesque fall, it is joined by the
Spray. At this point, close to the Banff Springs
hotel, the river is diverted at right angles
to the east and passes between Tunnel and
Rundle mountains. The valley of the Spray
river is floored with soft Permian and Jurassic
shales. The accompanying figure shows a
typical view of the Upper Banff shale (Permian),
exposed in Spray valley. This valley is defined
by a fault so that the beds in Sulphur mountain
repeat those exposed in Cascade and
Rundle mountains. The Fernie shales
(Jurassic) are characterized in certain layers
by the abundance of ammonites.

On the east slope of Sulphur mountain
are situated the hot sulphur springs. The
upper one is 500 feet (152-5 m.) above the
town. The water comes from the orifice at a
temperature of 114-2 degrees Fahr. (45-6° C).
This sulphuretted water has a marked medicinal
effect, and many people visit Banff on this
account. A second or middle hot spring
is 200 feet (60 m.) lower down the slope,
and a mile and a half (2-4 km.) farther to the

Legend

j K3 [ Upper Ribboned sandstone

K2 Kootanie CoaJ Measures

Lower Ribboned sandstone

Jurassic

Femie shale

Permian

Upper Banff 'shale

Rocky Mountain c/uartzite
Upper Banff limestone
Lower Banff shale
Lower Banff limestone

Devonian

Intermediate limestone

SHM Deronian0
H[H| Saw back format/ on

[ ^ Geological boundary

j I GeolopicaJ boundary

j | °(assumed)

Geological Survey,Canada

Banff

Miles

Kilometres

Legend

Geologica.1 Survey , Canada.

Route map between Banff <3.nd Golden

Miles

s IO

Glad

Q I Quaternary

H| Cretajceous
Jurassic
I Permian

j Carboniferous

KHB Devonian

| s I Silurian

] Ordovician

[ €3 j Upper Cambrian
V -C2 | Middle Cambrian

r^ei i Lower Cambrian

Pre - C&m briar/

I 1

j -1 Geological boundary

Kilometres

6 IO IS 20

1 89

KUomet^es northwest. The spring is not so strong as
the upper one, and the temperature of the water
is about 900 F. (32-2°C). A third or lower
spring is situated farther to the northwest
and about 50 feet (15 m.) above Bow river.
The water is at a lower temperature than either
of the upper two. Locally this spring is spoken
of as the "Cave and Basin", because the
spring rises into a cavern about 20 feet (6 m.)
in diameter. By means of an underground
channel it escapes to a natural basin formed in
the calcareous tufa deposited. A second cave
has been recently discovered a few yards farther
up the slope. The interiors of these caves are
coated with sulphur crystals. The Dominion
Park Commission is erecting a substantial
bath house at this spring for the accomo-
dation of the public. Other warm springs
are located in the bottom of Bow valley, about
the Vermilion lakes. All of these springs
are located in the Intermediate limestone
(Devonian).

From the summit of Sulphur mountain can
be seen the general monoclinal structure of
this portion of the Rocky mountains. The
successive ranges from the Cascade valley
westwards represent westerly dipping fault
blocks, which have become tilted along the
east side. On the north side of Bow valley
the Cascade, Vermilion Lake and Sawback
ranges form distinct units, the same beds
being repeated in each of these ranges.
83 m. Leaving Banff station the railway follows

132-8 km. along the broad swampy valley of the Bow,
on the right of which is a series of three small
lakes, called Vermilion lakes. The range to
the right is the Vermilion Lake range, in which
are exposed the westerly dipping Devonian,
Carboniferous, Permian and Jurassic beds.
85 m. This creek follows a fauk line which divides

136 km. the Vermilion Lake range from the Sawback
range. This depression leads to Edith pass,
beyond which can be seen Mt. Edith, which
is made up of vertically dipping Lower Banff

190

KHomSres. limestone. The steeply dipping beds on the
west of this creek belong to the Sawback
formation. This formation lies conformably
under the Devonian Intermediate limestone,
but the exact age is still doubtful, as no fossils
have yet been found in it. Lithologically,
a part of this series resembles the rocks of
Silurian age in the Beaverfoot range to the
west. To the south of the railway is the valley
of Healy creek which extends to Simpson
pass, and is the course followed en route to
Mt. Assiniboine, the Matterhorn of the Can-
adian Rocky mountains. Bow river has here
a meandering course, some of the lobes having
been cut through, to form oxbow lakes.
88 m. Sawback.— Alt. 4537 ft. (1,384 m.). West

140-8 km. of Banff the railway crosses the strike of the
formations in the Vermilion Lake and Sawback
ranges, but at this point the valley of the
Bow turns sharply to the northwest and follows
along the strike of the formations as far as
Laggan. The Carboniferous limestones dip at
about 650 to the southwest, so that smooth
cliffs formed along the bedding-planes are
characteristic of the Sawback range. Mt.
Hole-in-the-\Yall, to the north of the station,
is so called because it contains in its side a
cavernous opening. This cave at its outer
end is 50 feet (15 m.) in diameter, but becomes
smaller behind as the floor rises. It is about
150 feet (46 m.) long and is situated, 1,500 feet
(458 m.) above the railway, in the Lower
Banff limestone. The position of the Lower
and Upper Banff shales is always readily
recognized by a depression on the surface.
93 m. Massive — Alt. 4,600 ft. (1,402 m.). On

148-8 km. the south side of Bow valley, Pilot mountain
towers 5,000 feet (1,513 m.) above the railway.
The base consists of Devonian limestone, and
the peak is capped by Upper Carboniferous.
From the Intermediate limestone in Fossil
mountain, 10 miles northeast of Laggan, the
following Upper Devonian fauna have been
determined : — Spirifer whitneyi Hall ; Productella

I9i

Kilometres hallana Walcott ; Stropheodonta demissa (Con-
rad), Schizophoria striatula (Schlotheim) ,
Chenungensis var. arctostriatus (Hall), Phillips-
astraea verrilli Meek, Syringopora cf. perelegans
Billings, and other Devonian species.

A few yards beyond the west end of the
siding, the railway cuts through a down-
faulted block of dark brown Fernie shales
containing ammonites, which indicate that they
are Jurassic in age.
96-2 m. The upper part of Johnson creek separates

153 -9 km. Sawback range from Castle Mountain range.

It follows in a fault valley. Four miles from
its mouth the stream has been diverted to the
south by the down-faulted block of Jurassic
shales referred to above. From this point
there is an excellent view of Castle mountain
with its perpendicular cliffs and broad amphi-
theatre behind.

99 m. Castle — Alt. 4,660 ft. (1, 420 m.), is situated
158-4 km. at the base of Castle mountain. West of the
station the railway follows along the base of
this mountain for over 10 miles (16 -i km.).
The eastern end of the mountain is terminated
by a large pinnacle which, from the railway,
resembles the ruins of a massive castle; hence
the name. The accompanying illustration
shows the character of the rock in Castle
mountain. The upper slopes are Cambrian.
It is capped by the thin-bedded red-weathering
limestones and shales of the Bosworth formation
(Upper Cambrian). The perpendicular cliffs
at the top represent the Eldon formation.
This is the type locality and this formation
has a measured thickness of 2,728 feet (832 m.).
The Stephen formation is about 600 feet (183 m.)
thick, and forms a very flat talus-covered
slope, while the Cathedral formation below is
about 1,500 feet (458 m.) thick and forms
a precipitous slope. These three formations
are Middle Cambrian in age. The Lower
Cambrian beds are largely quartzitic and
form brush-covered, irregular slopes.

192

Kilometres Castle was an active town with about 1,500
people in 1884-86, but is now deserted. The
"boom" was caused by the discovery of copper
prospects in Copper mountain directly south
of the station on the opposite side of the valley.
Mining proved a failure. And there is now
only one of . the old timers, James Smith, living
here.

There are numerous foundations on this flat,
but most of the buildings have been burned or
torn down.

100 m. The Dominion government is building an

160 km. automobile road across the Rocky mountains
from Calgary to Golden. The road here
crosses the railway and Bow river; it follows
up Vermilion creek to the south, over the
Vermilion Pass, and down Vermilion river
to the Kootenay, thence into the Columbia
valley and down to Golden. The road is nearly
completed up to the pass, which, with an eleva-
tion of 5,264 feet (1,605 m-)» is the lowest
pass in this part of the Rocky mountains.
To the east of Vermilion Pass is seen the craggy
cliffs of Storm mountain (altitude 10,309 feet)
in the Middle and Lower Cambrian formations.
The lower rounded ridges to the east are formed
of Pre-Cambrian shales. The contact, appar-
ently slightly unconformable, is exposed at
the eastern base of Storm mountain.
105-5 m. Eldon— Alt. 4,817 ft. (1,468 m.). The
170-4 km. broadly rounded Bow valley is underlain by
the softer Pre-Cambrian shales included in
the Hector and Corral formations. The Pre-
Cambrian beds floor the Bow valley and the
lower slopes up to Kicking Horse pass, and
to the head waters of Bow river. This series
has been called Pre-Cambrian by Walcott
[4], because the beds are largely unfossiliferous
and underlie the Olenellus zone of the Lower
Cambrian. These beds represent a portion
of the Bow river group, defined by McConnell
[5]. A few brachiopod-like fossils were found
by the writer in a layer of Hector shale at the
base of Storm mountain.

193

Miles and
Kilometres.

112 m. Between this point and Laggan one has the

179-2 km. best view of the valley of Ten Peaks, also
Paradise valley and the majestic peaks of
the Bow range. The peaks which stand
out in prominence are a few of the Ten Peaks,
including Mt. Fay and Mt. Deltaform (11,225
ft. — 3,421 m.) ; also Mt. Temple (11,626 ft. —
3, 544 m.), the highest peak in the range
visible from the railway. On approaching
Laggan, Fairview, Aberdeen, Whyte, and Vic-
toria become visible.
113-9 m. The first and lowest exposure of Pre-Cambrian
182-2 km. occurs to the right of the railway. It is a
coarse pebbly sandstone containing pink felspar.

115 m. Laggan— Alt. 5,037 ft. (1,535 m.). From
184 km. this point, type localities for Cambrian and
Pre-Cambrian formations will be visited. A
driveway and a railway lead up to Lake
Louise and the Chalet. This lake is situated
over 600 feet (183 m.) above Bow river,
at the front of a large cirque which is occupied
at the south end by Victoria and Lefroy glaciers.
The lake is surrounded by Lower Cambrian
quartzites of which the St. Piran formation
stands out in prominence and forms precipitous
cliffs. The contact between the Lower Cam-
brian quartzites and the Middle Cambrian
limestones is well shown in the lofty mountains
about this valley. The illustration on page
178 shows the Mitre with Mt. Lefroy on
the right, Mt. Aberdeen on the left, and a
portion of the Lefroy glacier with a well
defined bergschrund. The cliffs are Lower
Cambrian, and the Mitre is capped with the
Cathedral limestone of the Middle Cambrian.
The pass to the right is called the Death Trap
on account of its dangerous position.

A visit will be made to Valley of the Ten
Peaks, and the mouth of Paradise valley
will be passed on the way. Both are typically
hanging glacial valleys with glaciers at their
upper termini. In the former the valley is

194

KUometres surrounded by ten gigantic peaks each of which
shows the Lower and Middle Cambrian
formations. Moraine lake lies in this basin
between a large moraine and the Wenchemna
glacier. Mt. Temple (11,626 feet), (3,543-6
m.), the highest in this part of the Rocky
mountains, stands between these two valleys.
The talus slope shown in the illustration on page
175 shows the position of the contact between
the Pre-Cambrian and the Cambrian. The
Middle Cambrian begins at the change in slope
in the cliffs on the left, and the peak is capped
by Upper Cambrian thin-bedded limestones of
the Bosworth formation.

Leaving Laggan station, a good exposure
of Pre-Cambrian slates and shales wiil be
visited within 200 yards (183 m.) of the west
end of the railway yards. The illustration
on page 173 shows the conformable contact
between the Pre-Cambrian shales of the Hector
formation and the Lower Cambrian quartzites.
This contact is exposed in the south end of
the ridge separating the Bow valley from the
much smaller valley of Bath creek.

116 m. One mile west of Laggan the railway leaves

185-6 km. the Bow river and follows up Bath creek to
the summit. Bow river continues toward the
northwest, to its source in Bow lakes, 20 miles
(32-2 km.) up the valley. The stream is
enlarged by water from Hector lake. Mt.
Hector (11,125 feet) (3,391 m.), with its
castellated cliffs of Lower and Middle Cambrian
formations, can be seen from the railway to
the right of Bow valley.

121-5 m. In a quarry on the right of the railway

194- 4 km.there is a good exposure of Pre-Cambrian

slates, in fresh condition. These shales and
slates are transported to Exshaw, where they
are used in the manufacture of cement. The
purplish and drab color of these rocks is char-
acteristic of the formation.
122 m. Looking ahead to the right can be seen the

195- 2 km.perpendicular cliffs of Mt. Daly formed in

Middle Cambrian limestones, with a typical

195

Kiiomlt^es c^ glacier, a fragment of the large Daly glacier,
on its eastern flank.

A few yards west of the crossing of Bath
creek there is a good exposure of Cambrian
basal conglomerate. It encloses fragments of
the underlying slate, but the exact contact
with the Pre-Cambrian is not visible along
the railway.

122-2 m. Kicking Horse Pass (The Great Divide) —
195-5 km. Alt. 5329 ft. (1,625 m-)- This is the con-
tinental divide. The pass, discovered by
Sir James Hector in 1876, is a saddle-like
depression about two miles broad carved out
by the ice. The grade from the pass to the
west into Kicking Horse valley is very much
steeper than it is to the east into the Bow valley.

To the right of the pass is Mt. Bosworth
in which there is exposed nearly 9000 feet
(2743 m.) of Lower, Middle, and Upper Cam-
brian strata. The Bosworth section was exam-
ined by Walcott (5) in 1908, this being the
first attempt to subdivide the Cambrian of
the Canadian Rocky mountains into form-
ations. From this point it will be seen that
the structure in the western slope of the Rocky
mountains represents the western limb of a
monocline; whereas the Cambrian basal con-
glomerate is exposed near the divide, the rocks
are Ordovician and Silurian in age in the last
range to the west.
125 m. Hector — Alt. 5,207 ft. (1,587 m.). The
200 km. stream entering the lake at this point is Cataract
brook. It drains Lake O'Hara and Lake
McArthur, and glaciers on Mts. Victoria,
Huber, Hungabee, Odaray, Cathedral and
Stephen. Wapta lake at the right of the
railway is the main gathering basin for the
headwaters of Kicking Horse river. Below
the end of the lake the river has cut a canyon
through the Middle and part of the Lower
Cambrian formations.
128 m. From this point there is an excellent view

204-8 km. of Yoho valley, a glacial U-shaped depression,
which heads in the Yoho glacier. The valley

196

Kilometres *s cut through Lower and Middle Cambrian
strata. At Takakkaw falls, 1,248 feet (380 m.)
high, the water cascades over Middle Cambrian
limestone. The same formation causes the
Twin falls, farther north in the valley, but the
fall is not as great.
129 m. Upper end of No. 1 Tunnel. Between the
206 -4 km. Pass and

131- 1 m. Lower end of No. 2 tunnel. Field, a dis-
209-7 km. tanceof about

eight miles (12-9 km.), there is a difference
in elevation of 1,160 feet (353-5 m.), of which
900 feet (274 m.) occurs within four miles
(6-4 km.). To overcome this steep grade
the Canadian Pacific railway has constructed
two spiral tunnels. The upper one (No. 1),
3,200 feet (982-4 m.) long, is in Lower Cambrian
quartzites in the base of Cathedral mountain.
The lower one (No. 2), 2,900 feet (884 m.)
long, is in Middle Cambrian limestones in
the base of Mt. Ogden. There is a difference
of 60 feet (18-3 m.) between the rails at the
ends of the tunnel, in both No. 1 and No. 2.
The average grade is now 2-2 per cent, whereas
the grade of the old road, now used as a wagon
road, is 4-4 per cent.

Before entering No. 2 tunnel, the glacier-
shaped Kicking horse valley is seen, with its
broad aggraded valley floor. On the left
of the valley is Mt. Stephen (10,485 ft. —
3,196 m.), and on the right is Mt. Field
(8,645 ft.— 2,636 m.).

132- 5 m. About one mile (i-6 km.) west of Cathedral
211 -2 km. station the railway passes through a short

tunnel in Lower Cambrian quartzites. Be-
tween this tunnel and the wagon road there
is a normal fault with about 3,000 feet (921 m.)
displacement. Mt. Stephen is on the down-
throw side, so that the Lower Cambrian
quartzites in the Cathedral mountain come
against the Eldon formation, at the top of
the Middle Cambrian, in Mt. Stephen. This
break has been called the Stephen-Cathedral
fault.

197

Miles and From this point there is an excellent view

Kilometres. p • r , - - .

of Mt. Stephen. I he base of this mountain
is Lower Cambrian and it is capped by Bosworth
formation (Upper Cambrian). The Cathedral
formation extends to the top of the great
North shoulder.

The Monarch mine is situated in Mt. Stephen
about 1,000 feet (305 m.) above the railway
in the Cathedral formation. The ore, con-
sisting of lead and zinc sulphides, is a replace-
ment deposit along a major and several minor
fissures. A concentrating mill, on the left
of the railway, has been recently constructed
and is separating about 80 tons of ore per
day.

The second short tunnel passes through
the St. Piran quartzite in the shoulder of Mt.
Stephen. The railway follows along the slope
of the mountain, gradually approaching the
level of the valley floor. At Field it is only
10 feet (3 m.) above the river.
137 m. Field — Alt. 4,064 ft. (1,239 m.). This

219-4 km. railway divisional point is the gateway to
Yoho valley, Emerald lake and Ice River
valley.

The famous trilobite fossil bed outcrops
in the Ogygopsis shale about 2,600 feet
(793 m.) above the railway on Mt. Stephen.
Walcott [6] has determined 32 species of
trilobita and brachiopoda from this lentile
of shale. This shale belongs to the Stephen
formation (Middle Cambrian.).

Another fossil bed recently discovered by
Walcott occurs in the west slope of Mt. Field,
in the "Burgess shale," which also belongs
to the Stephen formation. This fossil bed is
reached by Burgess pass and is shown in an
illustration on page 177. From this shale
Walcott [7] has determined trilobita, brachi-
opoda, merostomata, malacostraca, annelids,
holothurians and medusae.

West of Field the beds dip more steeply
to the west. A normal fault with the down-
throw on the west side, passes between Mt.

Miles and Stephen and Mt. Dennis. This is called the

Kilometres. r .

Stephen-Dennis fault.

Two miles (3-2 km.) west of Field the
Kicking Horse river becomes a narrow channel
and in one place passes under a natural bridge
formed in the Upper Cambrian shales and
slates.

[3-5 m. Emerald— Alt. 3,895 ft. (1,188 m.). There
'5-6 km. are over 300 feet (91-5 m.) of Pleistocene
from Field. lacustrine gravels along the sides of the
Kicking Horse valley. The Canadian Pacific
Railway Company has erected a gravel-washing
plant at the station, the gravel being used for
ballast after the clayey material has been
washed out.

On the north side of the valley five distinct
terraces can be recognized in these gravels
along the valleys of Emerald creek and the
Amiskwa river.

For the next four miles (6-4 km.) Kicking
Horse river has a broad alluvial flood plain,
nearly two miles wide in places.

Looking ahead to the right of the railway
red-capped peaks and ridges in the Van Home
range are seen. These red-weathering shales,
slates, metargillites and phyllites belong to
the Chancellor formation of the Upper
Cambrian, and overlie those beds exposed
on the top of Mt. Bosworth at the divide.

On the south side of the railway in the Otter-
tail range, these shales and slates are overlain
by the massive Ottertail limestone which forms
precipitous slopes. The accompanying figure
shows a gentle slope on the Chancellor shales
and a very steep slope in the Ottertail limestone.
Some of the peaks in this range are capped
by Goodsir shale, the lowest formation in
the Ordovician. The very sharp contact
exposed in Mt. Goodsir in the Ice River valley,
between the Cambrian, represented by the
Ottertail limestone and the Ordovician repre-
sented by the Goodsir shales, is shown in another
illustration page 180 (8). The fauna in those

199

shales determine the age of the beds. Mt. Good-
sir (11,676 ft.; 3,565 m.) is the highest in the
Rocky mountains near the railway. A glimpse
of this peak can be seen on the left of the rail-
way at about five miles (8 km.).

Ottertail escarpment, showing Chancellor formation forming talus-covered, undulating
surface; Ottertail limestone in cliffs; and Goodsir shales on gradual slopes.

8-2 m. Ottertail — Alt. 3,696ft. (1,127 m.). Forsome
13-1 km. distance on either side of the station the railway
cuts through highly sheared Chancellor shales
and slates which are here characterized by
their silken lustre and purplish gray color.
The river now flows almost due south at the
bases of Mt. Hurd and Mt. Vaux.
15 m. The railway turns sharply through an angle of

24 km. 120 degrees to the northwest around the end
of a ridge of Upper Cambrian limestone. The
river continues to the south for about two miles
(3-2 km.) and then makes a similar sharp
bend to the northwest. At this bend is Wapta
falls, formed in the highly sheared, steeply
tilted Upper Cambrian slates. The Beaver-
foot valley extends to the left of the railway,
and was the course followed by Kicking Horse
river in pre-Glacial time. The stream course
was diverted largely by morainal obstructions.
35069— 7A

200

Miles and
Kilometres.

17 m. Leanchoil — Alt. 3, 681 ft. (1,123m.) Looking

27- 2 km. east along the railway, the Ottertail range

lies in the background. Chancellor peak
(10,751 feet, 3,276 -8m.) is especially prominent.
Behind this ridge lies Ice River valley, in which
is exposed the only igneous complex in this
portion of the Rocky mountains. It covers
about 12 square miles, has the form of an
asymmetrical laccolith, and is alkaline in
composition. This is one of the few localities
in which sodalite is found in considerable quan-
tities.

Between the second and third peaks to the
left of Chancellor peak, the contact between
the dark coloured igneous rock, (an ijolite),
and the gray limestone can be seen from this
point.

22-9 m. Palliser — Alt. 3,283 ft. (1,001 m.). The
36-6 km. highly sheared Goodsir shales outcrop at many
places on either side of the railway. North
of the station is a fault-line scarp on the shoulder
Mt. Hunter. The up-throw has been on the
northeast side so that the Upper Cambrian
beds adjoin the faulted edges of the Lower
Ordovician shales.

The glacial gravels are over 200 feet (61 m.)
thick, and are frequenlly well terraced on
both sides of Kicking Horse valley.

West of this point the valley narrows, and
a canyon has been cut through steeply tilted
Ordovician and Silurian beds in the Beaverfoot
range.

28- 4111. Glenogle — Alt. 2,991 ft. (911-5 m.). The
45 -4 km. best exposure of the black, fissile, Graptolite

shales will be seen in the first small creek at
the west end of the railway siding. This
fauna is especially abundant in one thin layer
of this formation. Throughout the remainder
of the canyon the structure is complicated by
faults and overturned folds. The Silurian
beds are recognized as white quartzites and
gray massive dolomitic limestones. This form-
ation is highly fossiliferous in certain horizons.

201

KUomeu-es About one mile west of Glenogle there is
a mineral spring in the Silurian dolomitic lime-
stones. A yellowish calcareous deposit thickly
coats the rock over which the water flows.
Another spring rich in calcareous material,
occurs about one mile farther down to the right
of the railway. Some of the mineral spring
water from this canyon has been tested and
found to be rather strongly radioactive.

About half a mile east of Golden the valley
of Kicking Horse river opens out into the
Columbia valley. In the railway cut at this
point there is a good exposure showing the
gravels of the Columbia lying against the very
steep side of the old valley along the western
base of the Beaverfoot range. These stratified
gravels extend at least 350 feet (107-5 m0
above the river.
35-6 m. Golden — Alt. 2,580 ft. (786 m.). Kicking
572 km. Horse river joins the Columbia river at this point.

BIBLIOGRAPHY.

1. Dowling, D. B Cascade Coal Basin, Geol. Surv.

Can., Pub. No. 949, 1907.

2. McConnell, R. G. .Ann. Rept., Geol. Surv. Can., Part

D, 1887, p. 23.

3. Shimer, H. W Lake Minnewanka Section: Sum.

Rept., Geol. Surv. Can., 1910.

4. Walcott, CD Pre-Cambrian Rocks in Bow valley:

Smithsonian Misc. Coll., Vol. 53,
No. 7, 191 1 .

5. Walcott, CD Cambrian Section of the Cordilleran

Area: Smithsonian Misc. Coll., Vol.
53, No. 5, 1908.

6. Walcott, CD Mt. Stephen Rocks and Fossils:

Canadian Alpine Journal, Vol. 1,
No. 2, p. 292.

7. Walcott, CD Smithsonian Misc. Coll., Vol. 57,

Nos. 2, 3, 5, 6, 1911 and 1912.

8. Allan, J. A Geology of the Field Map-Area:

Sum. Rept., Geol. Surv. Can., 191 1,
p. 180.

35069— 7§A

202

ANNOTATED GUIDE.

(Golden to Savona.)

Reginald A. Daly.

Miles and
Kilometres.

35-3 m. Golden— Alt. 2,578 ft. (786 m.). The train
56-8 km. here enters a typical section of the Rocky
Mountain trench, a through-going Cordilleran
feature of a length hardly to be matched in
any other mountain chain. About 100 miles
(160 km.) above Golden is the source of the
Columbia river, which, except for a short
distance, occupies the main trench as far as
the beginning of its "Big Bend", 87 miles
(140 km.) below Golden.

The town overlies Ordovician shales; the
long bastion-like escarpment of the Dogtooth
range (Purcell Mountain system) across the
valley is composed of the uppermost slates,
schists, and quartzites of the Beltian series.
The trench is, in fact, here located on a master
longitudinal fault of a throw at least equivalent
to the entire thickness of the Cambrian group
(5700 m.). The fault plane runs close to
the lower cliffs of the Dogtooth mountains.
It has clearly located the trench, which, how-
ever, has been specially widened by erosion
on the softer Paleozoic rocks ranging east of
the great break. The fault probably dates
from the Laramide (post-Laramie and pre-
Eocene) revolution. The colossal denudation
represented in the destruction of the uplifted
Purcell block must have consumed much of
Tertiary time. What part of the period was
concerned with the excavation of the visible
trough it is still impossible to say. The work
was done in stages. In the later Tertiary the
trench has been increased to widths of three to
six miles (5 to 10 km.), a past-mature river

Legend

Ordovician and Upper Cambrian

Lower Cambrian and Beitian

Ross and Sir Donald quartz ites

Nakimu limestone

Cougar formation

Albert Canyon division
of Selkirk Series

Shuswap orthogneisses , chiefly

Shuswap sediments ,
cut by granitic sills

203

valley of first magnitude. Probably during
the late Pliocene the region was uplifted and
a narrower trough sunk in the old valley floor.
Remnants of that floor are visible in the trench
at elevations of 650 to 1,000 feet (200 to 300 m.)
or more above the river. The bed-rock form
has been seriously affected by Glacial erosion
and deeply covered with drift, into which the
Columbia has cut, with the development of
terraces and a broad flood-plain.

The Pleistocene deposits are so thick and
continuous in the trench that bed-rock crops
out at the railway only twice between Golden
and the 53rd mile-post, a distance of 28 kilome-
tres. Practically as far as the observer at Golden
can see on the southwest side of the trench,
both north and south of the town, the rocks
are silicious sediments of latest Beltian age.
On the northeast side, the heights are chiefly
composed of the Silurian (Moberly Peak) or
Ordovician formations. After leaving Golden
the first important exposure of rock at the
railway track is on the right, at the crossing
of Blaeberry river (45 mis.), where the Goodsir
(Ordovician) shales are dipping at an angle
of about 550 to the northeast. These, like all
the other Paleozoic strata seen in the trench,
are more or less crumpled and cleaved, indicating
great disorder in this broad band followed by
the trench. On the whole, however, the
Cordilleran strike is preserved here, as it is all
across the Middle ranges as far as Albert
Canyon.

Purcell Mountain System. — The rugged
wall on the west side of the trench is the north-
easterly limit of the group of the high peaks
here included in the Purcell system. As shown
in the accompanying structure section, the
rocks in this escarpment form the northeastern
limb of a wrinkled syncline adjoining a well
developed anticline along which the valley of
Quartz creek has been excavated. The com-
pound syncline has suffered intense glacial
erosion, producing abundant alpine horns;

204

hence the appropriate name, Dogtooth moun-
tains, for this division of the Purcells, situated
between Quartz creek and the Columbia. A
narrower, tightly compressed syncline forms
the adjacent lower and less rugged range,
called the Prairie Hills. That mountain group
overlooks the broad Beaver River trough
which, between Six Mile Creek (68-0 mis.)
and a point many miles south of Beaver Creek
(78-0 mis.), is an anticlinal valley excavated
in the relatively friable rocks of the Cougar
formation.

The Purcell mountain system is thus essen-
tially a mass of Beltian strata folded with
comparative regularity. The Cordilleran strike
(here N. 300 W.) is generally well preserved
throughout the whole area covered in this
part of the Purcell system, as it is in the much
broader section mapped at the International
Boundary, far to the south. However, the
folds show local disorder; they were accompanied
by subordinate fractures and, where closely
appressed, by mashing and by the development
of slaty cleavage.

Three kilometres beyond Donald, soon after
crossing the river, the railway enters a long
series of rock cuts, where the river leaves the
main trench, and is cutting a long canyon
across the folded and mashed Paleozoics. On
the right bank of the river, for a distance of
many kilometres, is a mountain block separated
from its structural equivalent, the Dogtooth
range, by a late Glacial diversion of the river
from the broad trench on the east. The
Paleozoic shales and limestones, standing at
high angles, can be seen in the walls of the
canyon. Near the tunnel marked as 54-6
miles from Field, fossils of late Upper Cambrian
age, including an Illenurus and a genus like
Dicellocephalus, have been found in abundant
calcareous nodules formed in shale and impure
limestone.

The strata grow more and moie disordered
until the great Trench fault is reached, at a

205

KUometres. point about 3 kilometres east of Beavermouth
station. There the Paleozoic shales and lime-
stones abruptly cease and the train runs over the
quartzites, slates, and schists of the Beltian
Cougar formation. An exceptionally thick and
massive quartzitic member of this formation
soon appears in bold bluffs on the left ; the same
band of rock crosses the river at Beavermouth
and continues on a N. 300 W. strike into the
mountain to the right of the Columbia.
63-2 m. Beavermouth — Alt. 2,430 ft. (741 m.), is

101-7 km.situated at the confluence of Quartz creek
and the Columbia river. The creek represents
a case of stream diversion. Its former course
lay to the eastward of the high mass of quartzite
southeast of the station. Across that rock
it had cut a narrow canyon about 1 • 2 kilometres
in length and about 75 metres in average depth.
Its floor is nearly 300 m. above the Columbia.
Specially rapid (Glacial?) erosion on a band
of fissile schists paralleling this quartzite on
the southwest caused the diversion of the creek
to its present course. The high-level canyon
is now nearly dry and is open at both ends.
Placer mining for gold has been carried on
for some years along Quartz creek.

Two kilometres beyond Beavermouth the
railway turns sharply away from the Columbia
into the transverse valley of Beaver river,
where the Prairie Hills syncline is exposed in a
long succession of deep rock-cuts. The syncline
is tightly closed. The first outcrops, seen where
the railway first meets the Beaver, are
cleaved quartzites and slates of the Cougar
formation. These are often crumpled in detail
but the general dip is about 8o° to the south-
west. At the 65 -6-mile point the overlying
Nakimu limestone, here reduced by shearing-out
to a single vertical bed a few metres thick, is

65-8 m. found. Close by is The Gateway, where the

105-8 km.vertical Ross quartzites, forming the heart of
the syncline, are well exposed. This is the
only section where one has a good oppor-
tunity of seeing this important formation close

206

at hand. Its habit is somewhat abnormal
on account of unusually intense cleaving under
tangential stress. Where seen outside this
Prairie Hills syncline, the Ross quartzite is
more massive. All or nearly all of the formation
here exposed is of Beltian age; the younger,
Lower Cambrian beds may not appear at
this low level in the fold.

The southwestern limb of the syncline becomes
identifiable at a point nearly 2 kilometres beyond
the bridge over the river, where the Nakimu
limestone with steep northeasterly dip crosses
the railway. The train then runs over the
Cougar formation with similar dips until,
at a point about 2 kilometres beyond Sixmile
Creek station, the dip becomes vertical or
disordered. At that locality is the axis of the
Beaver River anticline, trending N. 300 W.

Purcell Trench — As the train slowly climbs
the steep grade to Bear Creek station, an excel-
lent view of the Purcell Trench in its northern,
relatively narrow development, is obtained.
With remarkable straightness this primary
feature of the Cordillera continues 40 kilometres
S.S.E., to the head of the Beaver river and
then down the Duncan to Duncan lake and
the long Kootenay lake. The trench ends'
at Bonner's Ferry, Idaho, where it is entered
by the transverse valley of the Upper Kootenay
river. The total length of the trench is about
350 kilometres. West of it is the Selkirk
Mountain system; east of it the group of ranges
to which the inclusive name, Purcell system,
has recently been applied.

Here in its northern part the trench is an
erosion trough opened on the axis of a broad
anticline which has been demonstrated for a
distance of 30 kilometres and probably extends
still farther south. At the International Boun-
dary, the trench is considerably broader and is an
erosion trough located on a longitudinal fault
of the first order. Elsewhere, the origin of
this depression has not been determined.

207

The trench has been deepened and widened
by Glacial erosion, with the resulting devel-
opment of hanging valleys. The railway
crosses several of these, in which the streams
have already cut deep gorges in the schists
and fissile quartzites. The walls of the trench,
especially on the southwest side, are ornamented
with scores of cirques, many being still deepened
by living glaciers.

Excepting a few of the highest peaks, the
entire mountain wall visible on the Purcell
side of the trench is composed of the thick
Cougar formation dipping steeply to the E.N.E.
All the rocks in the lower slopes of the Selkirk
wall belong to the same formation, here dipping
steeply under the Nakimu limestone and the
massive Ross quartzite, of which most of the
highest peaks of the Selkirks are constituted.

78-0 m. Bear Greek station — Alt. 3,663 ft. (1116
125-5 km.m.). Below this point, near the confluence
of Bear creek and Beaver river, the railway
company is about to pierce a two-track tunnel,
7 • 5 kilometres (4 • 6 miles) in length . It will cross
the main divide of the Selkirks and emerge at the
railway loop near Glacier. One of the main
objects of this boring is to cut out of the line of
traffic the long chain of yet more expensive snow-
sheds now necessary between Bear Creek and
Rogers Pass stations.

Beyond Bear Creek station the line turns up
the creek and crosses the summit syncline of
the Selkirk range. The upper beds of the
Cougar formation and the Nakimu limestone
are quickly traversed. On the left, above the
forest of the canyon bottom, can be seen the
thick rusty quartzites of the Ross formation,
overlain by the gray, likewise massive, Sir
Donald quartzite. The impressive horn of
Mount Macdonald is composed of this youngest
member of the Selkirk series, there forming
an open, subsidiary syncline, which is continued
into the still invisible peaks of Mt. Tupper
on the north.

Excursion C i.

Mt. Tupper from Rogers Pass. Slopes underlain by Sir Donald quartzite.

209

Kiiom?tnres ^s ^e tram emerges from the last snow-shed,
the western limb of the sharp anticline, shown
in the general structure section, may be seen
on the left.

84-1 m. Rogers Pass — Alt. 4,302 ft (1,311 m.).
135-4 km. This station is situated on the axis of the main
Selkirk syncline. The fold is here broken and
faulted but the flat-lying beds of the axis can
be seen, in clear weather, on the slopes to the
north-northwest. The eastern limb is clearly
apparent but the western limb is best exposed
in the upper canyon of Bear creek. An oblique
view of the subsidiary folds already passed
over may be had toward the northeast, in
the crags of Mt. Tupper.

The railway follows the axis of the main
87-3 m. syncline to Glacier — Alt. 4,086 ft. (1,245 m.).
140-5 km. Here the Illecillewaet and Asulkan glaciers are
reached by good trails. The former drains the
Illecillewaet snowfield (25 square km. in area)
at its northern end, while the Geikie glacier
drains it at the south. The Asulkan glacier
is one of the several sheets heading on the
rugged ridge culminating in Mt. Bonney. All
of the glaciers are rapidly retreating, as
illustrated in the accompanying figures.

The special map and section of this region,
makes a detailed description of the local geology
superfluous, but some remarks may be helpful.

The noble peak of Mount Sir Donald (10,808
ft. 13,292 m.) to the southeast is composed of
the Sir Donald quartzite, well jointed in sheets
which from a distance deceptively resemble
individual strata. The true dip of the quart-
zitic sandstone is to the E.N.E., at angles
varying from 6o° on the western slope to 150
or less at the eastern foot of the horn. Mount
Sir Donald is, in fact, a remnant of a long,

Illecillewaet glacier in August, 191 1. Photograph by H. Ries.

Illecillewaet glacier in August, 191 2. Comparison with preceding figure shows recession
of the ice-front during the year preceding. Photograph by H. Ries.

211

narrow, synclinal wrinkle adjoining the great
Beaver River (Purcell trench) anticline. A
subsidiary anticlinal axis, paralleling this syn-
cline on the southwest, runs nearly through
the crest of Eagle and Avalanche mountains
and is probably coincident with the one just

Mt. Sir Donald from Eagle mountain; Mt. Uto in foreground. Photograph by Howard

Palmer.

west of Mt. Macdonald summit. The western
limb of this fold is also the western limb of
the syncline followed by the railway from
Rogers Pass to Glacier.

Another local anticline in the quartzite is
well exposed near tree-line on Mt. Cheops
and is continued across the Illecillewaet into
Mt. Abbot. Some faults and numerous small
slips, parallel to the general strike, have com-
plicated the structure between Mt. Sir Donald
and Cougar creek. On this account, and
because of the close similarity of the Sir Donald

and Ross quartzites, it has proved very difficult
to map the exact contacts of these two forma-
tions. Nearly all the cliffs from the hotel seem
to be composed of the Sir Donald formation.
In spite of local complications, the upper
valley of the Illecillewaet river, including the
neve region, is to be considered as lying in the
axis of the main Selkirk syncline. This view
is substantiated by the easterly dip of the
Nakimu limestone, exceptionally well exposed
on Cougar mountain and Ross peak.

The character of the Sir Donald formation
may be studied in the many large blocks strewing
the floors of the valleys above the hotel. The
essential similarities of the quartzitic sandstone,
grit, and occasional conglomerate to the differ-
ent phases of the St. Piran formation in the
Rocky mountains (Lake Louise and elsewhere),
are so many and so special that these formations
have been correlated with much confidence.
A general stratigraphic comparison, has in
fact, referred the Sir Donald and the upper
beds of the likewise unfossiliferous Ross quart-
zite to the Lower Cambrian.

A highly characteristic feature of all these
formations is the abundance of bluish, opalescent
quartz grains and pebbles, which are also found
at many horizons in the Cougar formation,
The source of this quartz is to be found in
the coarse orthogneisses and pegmatites of
the Shuswap terrane bordering the Selkirks
on the west. The sometimes abundant feldspar
grains in these sediments are microcline,
microperthite, orthoclase, and acid plagioclases
— all largely derived from the same source.
Mineralogical composition, general stratigraphy,
and field habit indicate that the Selkirk series
represent the northern continuation of the
thick Belt series of Montana and Idaho.

In the Selkirk mountains, there can be no
doubt as to the conformity of the rocks here
referred to the Lower Cambrian with the older,
enormously thick mass of strata (Beltian
system) to be seen between Ross Peak and
Albert Canyon stations.

213

Miles and From Observation point on Mt. Abbot

Kilometres. . 1 i • • 1 1

one obtains an extended view in the heart
of the Selkirk synclinorium. On the right
and in front are the structural features so far
noted. On the left, at the eastern end of
Cougar mountain the Nakimu limestone is
conspicuous in a steep rock-slope bare of
vegetation. Farther west, to the limit of
vision, the mountains are composed of the older
Beltian strata, dipping monoclinally to the
northeastward.

Leaving Glacier, the train descends to the
"Loop", where the Selkirk tunnel will emerge
at its western end. On the left a brief view
is obtained of the Bonney glacier; on the right,
a closer view of the gray Nakimu limestone
on the western slope of the Cougar valley.
One kilometre beyond the Cougar watertank,
the limestone can be seen, continuing on the
regional strike over the col between Green
peak and Ross peak. The Caves of Nakimu
(Caves of Cheops) are irregular tunnels occupied
by Cougar creek in a subterannean part of
its course along the limestone. Here we have
the most westerly outcrop of this invaluable
guide to the stratigraphy of the Selkirks.

For the next 5 kilometres the train runs over the
Cougar formation, here distinctly more massive,
homogeneous, and quartzitic than on the eastern
slope of the Selkirk range. To right and left,
heavy beds of white quartzite, interrupting
the dominant, gray and rusty strata, can be
seen. A narrow synclinal wrinkle affects the
95 m. general monocline about 1 kilometre west of Ross
153 km. Peak station and, in good light, can be
discerned in the high bluff on the left.

Four kilometres beyond Ross Peak station
(94-2 mis.), the quartzitic Glacier division
of the Selkirk series conformably overlies the
dark-coloured metargillites of the Albert Canyon
division. The position of the contact between
98 m. these two contrasted formations can be seen
158 km. on the slope southeast of Flat Creek station.

From this contact, crossing the railway near

2I4

the 97th mile-post, to the Illecillewaet gorge,
a distance of 10 miles (16 km.), the route
crosses the northeasterly dipping beds grouped
under the name, Laurie formation (See p. 134).
Its apparent thickness is extremely great
and, as yet, no evidence of large-scale duplica-
tion of strata has been discovered. Dawson
considered that these beds have a synclinal
structure, (G.M. Dawson, Bull. Geol. Soc.
America, Vol. 2, 1891, p. 174), but detailed
work has shown that they form a monocline
accidented by rare, narrow strike-zones of
crumpling. The most important of such zones
is clearly visible from Laurie station (100-5 m-)
in the long gulch due northwest of that point.
Allowing liberally for all such evidences of
repetition, the Laurie formation is still to be
credited with a minimum thickness of over
4,500 metres.

From Flat creek to Illecillewaet (102-8
mis.; 165-4 km.) the dip averages about 500
to the N.E. The dark-gray to black, often
highly carbonaceous and pyritous metargillites
are well exposed in occasional long railway
cuts. They are remarkably homogeneous for
a nearly continuous exposure of 500 to 1,000
metres at a time. The principal variations
consist in the alternation of more massive
phases with the dominant fissile metargillite;
rare, thin beds of carbonaceous limestone are
found but the quartzitic interbeds noted in
the columnar section do not crop out at the
railway (see p. 134). Though the metargillite
usually has a phyllitic appearance, this is not
due to dynamic metamorphism. Schistosity
and bedding are almost always parallel, and
here as usual in the entire Selkirk series, the
recrystallization of the original muds was
accomplished under the static condition of
deep burial, and before orogenic deformation.

At Illecillewaet (102-8 mis.) the dip has
flattened to io° — 150 N.E. , with local crumpling.
The dip increases to 250 and then to 400 N.E. at

Geological Survey , Canada..

Albert Canyon

Miles

Legend

Vesicular basalt sill

Minette dike

Laurie formation;
chiefly metargillite

Euartzite member of
zurie formation

lllecillewaet quartzite

Mo ; Moose metargillite

tl fi 1

^|L°iJ

If tn

Limestone

Basal quartzite
(arkose)

Sill of biotite granite
(orthogneiss, member of
Shuswap terrane)

Shuswap complex
(chiefly igneous)

Shustvap Terhstne Selkirk series

Section &long line A-B C

215

Miles and
Kilometres.

107- m. Illecillewaet Gorge (Albert canyon) — Alt.

172-2 km. ca. 2,450 ft. (747 m.). In the gorge an excellent
view of the lower beds of the Laurie group is
obtained. A thickness of about 200 metres
is represented in continuous outcrop. A few
thin lenses of blackish limestone and the basal
15-metre bed of light gray limestone (seen
at the west end of the rock cut) are intercalated
in the dominant metargillite. In the railway
cut may be noted the only intrusive rocks
known in our section between Glacier and
Albert Canyon station. One of these is a
narrow N-S. trending, nearly vertical dyke
of minette, with small, completely altered,
phenocrysts of augite. The other is a I -metre
sill of common, highly vesicular (!) basalt,
which locally breaks across the bedding of the
metargillite.

On the way to Albert Canyon station, a few
rock-cuts in the Illecillewaet quartzite and
Moose metargillite are passed. On the right
the north branch of the Illecillewaet joins the
main river.

109 • 4 m- Albert Canyon station — Alt. 2,221 ft.

176-0 km. (677 m.). A prolonged stop is made at this
point for the double purpose of viewing the
basal unconformity between the Selkirk series
and the Shuswap terrane; and of becoming
acquainted with an igneous phase of the latter
series of rocks.

About 800 metres from the station, on the
northwest bank of Albert (Moose) creek, the
zone of unconformity has been laid bare for in-
spection. The high precipices visible on the east
and north are composed of the dark-coloured
strata of the Moose metargillite, Illecillewaet
quartzite, and Laurie metargillite, dipping to the
northeast. The Moose formation is largely
hidden beneath the thick forest on the ridge due
south but preserves its monoclinal attitude to the
underlying limestone. This fine-grained marble
is seen at the crossing of Albert creek, where
35069— 8a

2l6

it passes, by interbedding, into the "basal
quartzite." (See p. 133).

The unconformity is here not marked by a
conglomerate but by a fine-grained feldspathic
sandstone, very similar in appearance to the
altered orthogneiss beneath. The basal quart-
zite is interpreted as a statically (and dynami-
cally?) metamorphosed arkose sand derived
from the adjacent orthogneiss and washed but
a short average distance from the parent,
pre-Beltian ledges. It is practically impossible
to indicate the exact plane of the unconformity,
but it may be approximately located at the
horizon where aplitic dykes cutting the ortho-
gneiss cease to be visible in the quartzitic
rock. The uncertainty is partly due to the
intense static metamorphism of older and
younger rocks alike; partly, to the deep
weathering of the orthogneiss before it was
covered by the bedded arkose. Microscopic
study shows that, for depths of 60 to 75 metres
stratigraphically below the surface of uncon-
formity, the orthogneiss has been thoroughly
altered. This alteration is apparently only
explicable as due to profound secular weathering
preceding deep-burial metamorphism.

Opportunity will be afforded for a more
extended study of the orthogneiss itself. It
has the form and relations of a broad laccolith or
sill, with a thickness of 1000 metres for the part
still remaining after the Beltian erosion. Along
the railway the mass can be well seen to show
a persistent gneissic structure which is closely
parallel to the bedding and fissility of the over-
lying Beltian strata. The lower contact of
the sill crosses the railway at a point about 2000
metres west of Albert Canyon station. There the
ancient granitic magma was clearly intruded
along a plane parallel to the banding in dark
schists probably in part of sedimentary origin.
These bedded Shuswap rocks and the great
intrusive sheet evidently lay nearly horizontal
while the Beltian strata were being deposited
upon them. Their flat position was typical

Excursion C i

218

of the rocks of the Shuswap terrane until the
revolution which flexed the Rocky Mountain
Geosynclinal into the folds of the Selkirk
range.

The thoroughness of the static metamorphism
suffered by the orthogneiss is very striking.
In part the completeness of the recrystallization
of the granite may be explained by burial
under the enormous mass of geosynclinal sedi-
ment, but it should be noted that similar
metamorphism is shown in the Shuswap
orthogneisses far to the west where the Beltian-
Cambrian strata were, apparently, never de-
posited in great strength. It seems probable
that the advanced static metamorphism of
the older Shuswap rocks was already accom-
plished in pre-Beltian time.

At this section along the railway track,
one can see samples of the many aplitic and
pegmatitic dykes cutting the orthogneiss and
schists beneath it. The abundance of these
igneous intrusions here, together with their
entire absence in the adjacent Beltian strata,
is one of the leading proofs of an important
erosion unconformity at the base of the Selkirk
series.

From the noth mile-post, near Albert
Canyon, to Shuswap station, 116 miles (186-7
km.) farther west, the railway runs almost
entirely over the Shuswap terrane. For the
first 30 kilometres the line crosses a dominantly
igneous phase of the formations composing this
second principal province of the Canadian Cor-
dillera. Biotitic and hornblendic orthogneisses
are the chief rock types until the Columbia river
at Revelstoke is reached. These metamorphosed
granites are all pre-Beltian but show different
dates of intrusion. The oldest masses observed
are generally hornblendic and are sills cutting
coarse sedimentary (?) mica schists; or are
larger bodies (batholiths?) without clear indica-
tion of shape. The hornblendic granites seem
to have been statically metamorphosed into
gneisses at an early date, for the younger,

220

KUomeu-es generally biotitic orthogneisses character-
istically occur as sills following a pre-existent,
flat-lying foliation in the older rocks. The
abundant masses of the later group were them-
selves rendered gneissic by a similar type
of metamorphism and then injected by myriads
of thinner sills, dykes, and chonoliths of white
or pink pegmatite and aplite. These youngest
members of the complex are less affected by
metamorphism, though a gneissic structure
parallel to sill-contacts is often seen also
in them.

The whole assemblage of rocks is in striking
contrast to that in a normal batholithic province
of a post-Cambrian date of intrusion, and one
cannot but suspect that some of the conditions
of rock formation in this typical "Archean"
field were peculiar to an early epoch in the
earth's history.

The gneissic complex is not well exposed in
the Illecillewaet valley except in a few places
where forest fires have bared the ledges. An
119-6 m. example is seen on the

192 km. Twin Butte Station left, for several kilo-
Greely Siding metres between Twin

Butte station and
Greely siding (124-2 mis.; 199-5 km.).

Near the 128th mile-post the river cascades
over schists and gneisses on which it has been
locally superimposed through its own alluvium.
At this point is the power plant of Revelstoke.
As the train turns sharply to the right, one sees
the fore-set beds of the delta built by the
Illecillewaet into the Columbia valley when
it was here laked, with a water level about
70 metres above that of the present Columbia.
It is probable that this water-body was a great
expansion of the existing Arrow lakes.
130-3 m. Revelstoke — Alt. 1,492 ft. (455 m.) an
209 • 7 km. important distributing centre in the interior
trade of southern British Columbia.

The orthogneisses, aplites, and pegmatites
can be easily studied on the mountain slope
rising directly from the railway yard.

Geological Survey, Canada.

Route map between Revelstoke and Ducks

Miles

S f 3 % I O 5 IO IS ZO

•5 b

Legend

Oligocenet?)

Hawloops Volcanic Group

Triassicfand 'Lower Jurassic?}
Nicola.Group

Adams Lake greenstone
Bastion schists
Sicamous limestone
Sill-sediment complex

Jurassic (?)
Batholithic granite

Intrusive granite of Shuswap Terrane
Shuswap orthogneisses, chiefly

Kilometres

221

The town lies in the ' Selkirk Valley, ' namely,
that part of the Columbia river valley which
bounds the Selkirk mountain system on the
west and separates it from the long Columbia
system, which across the valley rises to heights
approaching 9,000 feet (2,743 m0- This long
depression has a complex history and is of com-
posite origin, though the details of neither have
been worked out. Over most of Revelstoke
mountain, north of the town, the strikes average
about N.N.W. — S.S.E., a Cordilleran direction
corresponding probably to fault-blocking during
one of the post-Cambrian periods of mountain-
building. Across the river the strikes average
nearly E. — W. At its eastern bank, 5 kilometres
above Revelstoke, these structural lines are
found in close proximity, indicating a N. — S.
fault on which the river is located. Other local
evidence agrees with the view that this part
of the Selkirk valley has been formed by erosion
on a longitudinal fault of unknown but possibly
considerable throw. The downthrow is prob-
ably on its eastern side.

Along the branch railway to Arrowhead,
44 kilometres southward from Revelstoke, one
may observe the prevailing low dips in the
Shuswap terrane.

From Revelstoke to Kamloops the mile-posts
are numbered in a new series, beginning in the
east, and distances are stated accordingly.

At the crossing of the river one notes its
increase of size, accomplished in its 300-kilo-
metre journey from Beavermouth where it was
last seen. In that distance the river has rounded
the northern end of the Selkirk range, and it
is here flowing south toward the lava fields
of Washington State. After running over one
of the terraces characteristic of this valley,
the train reaches some extensive artificial cuts
in the Tonkawatla paragneiss. (See page 123.)

The normal orthogneisses, developed as thick
sills and many dykes cutting the sediments and
problematic basic schists, begin to appear as
the low divide of the Columbia range is approa-
ched, near Clanwilliam.

222

Miles and
Kilometres.

8*9 m. Clanwilliam station. — Alt. 1,812 ft.
14-2 km. (552 m.). The rock-cuts here afford excellent
from Rev- exposures of a dominantly sedimentary phase
elstoke. of the Shuswap terrane. Paragneisses, mica
schists, quartzites, and subordinate limestones
(cut by granite sills) are flexed into an anticlinal
fold pitching to the west. Tonkawatla creek
and the deep col at the divide are located in the
heart cf this fold. The stratigraphic place of
the sediments in the Shuswap series is not clear.
The older beds are much like the Tonkawatla
formation, and the quartzites have striking
resemblance to the Chase formation exposed
near Shuswap village. The still younger mica
schists overlying the quartzite may represent
the Salmon Arm formation. (See p. 124.)

At the western end of Victor lake, 2 kilometres
west of Clanwilliam, a 200-metre sill of biotite
granite has been thoroughly sheared and its
femic constituents, especially the mica, have
been segregated in thick, black bands. This
strikingly banded orthogneiss is a result of
dynamic metamorphism which is comparatively
seldom exhibited in the Shuswap terrane.
14-7 m. . From Three Valley station to Sicamous
24-8 km. (45-1 mis.) the line runs through a field of
orthogneisses cutting rarely exposed, rusty mica
schists, probably of sedimentary origin. Strong
jointing and the rissility of the schists are con-
ditions which have led to extensive land-slides,
visible at and for some kilometres beyond
Three Valley.

21 1 m. Mitikan Siding — Alt. 1,300 ft. (396 m.).

33-8 km To the south may here be seen a high bluff
seamed with many pegmatitic and aplitic sills.
From a more commanding position their
number in this slope has been estimated to
exceed two hundred ; their thicknesses range
from 1 metre to about 200 metres. They cut
rusty crystalline schists which are in part
sedimentary, enclosing occasional thin beds of
limestone.

Excursion C i.

Quartzites, mica schists and paragneisses, showing coincidence of bedding and
schistosity; Shuswap series. At Summit lake, Columbia range,
in railway section.

224

Miles and From Taft station (24-5 mis.) nearly to

Kilometres. 11- • i

Sicamous the line runs over massive ortho-
gneiss generally rich in hornblende and thus
contrasted with the dominant biotitic gneisses
of the Shuswap terrane. Near Taft the horn-
blende gneiss is in sill relation to the rusty
(metasedimentary?) schists, but beyond Craigel-
lachie (28-5 mis.) it seems to have the con-
tinuous character of a batholith or extremely
thick laccolith.

Approaching Sicamous, the train crosses the
delta of the Eagle river which has grown so far
as to nearly isolate Mara Arm from the main
Shuswap lake.

45-1 m. Sicamous — Alt. 1,147 ft. (350 m.). The
72-6 km. Shuswap lakes have a total length of about
150 kilometres. They represent profound changes
in the drainage system under the influence of
Pleistocene glaciation. Not only were water-
divides and stream directions modified at
that time; the graded valley-floors were con-
verted by Glacial erosion into series of rock
basins. Drift barriers have also co-operated in
the formation of these fiord-like lakes. The
greatest depth recorded for the Shuswap lakes is
447 feet (136 m.), measured about II kilometres
north of Sicamous. The neighbouring Adams
lake, 70 kilometres long and 1,200 feet (366 m.)
deep, is a pure type of rock basin. Part of its
floor is almost at sea-level.

From Sicamous the excursionists will obtain
their first view of the Belt of Interior Plateaus
here merging into the more rugged Columbia
range just traversed. The origin of the upland
facets of these plateaus is a problem not yet
completely solved. As a whole, however, they
represent a late Miocene or early Pliocene
land surface, dissected by streams revived
because of the general Cordilleran upwarp
during the Pliocene period. (See pp. 162-164.)

At and west of Sicamous station a partial
section of the Sicamous limestone (p. 124) may
be studied. It occurs in a fault-block showing
the exceptional Cordilleran N.W. — S E. strike,

226

with northeasterly dip. As one goes westward
he descends in the series and finds the limestone
becoming increasingly charged with sills of
orthogneiss and aplite. Near the 47th mile-
post the limestone is apparently underlain
by a massive quartzite interrupted by films and
thin beds of coarse muscovite schist. This
may represent a siliceous member of the Salmon
Arm formation or else the younger Chase
quartzite. The coarseness of the mica schist
and the massiveness of the lowest beds of lime-
stone are explained by the thermal metamor-
phism exerted by the abundant sills. In the
southeastern slope of Bastion mountain across
the lake, the coarse, glittering (Salmon Arm)
mica schists cut by many granitic sills pass up
gradually into a fine-grained metargillite almost
free from intrusives, and the latter rock is
conformably overlain by the normal, fissile
Sicamous limestone.

One of the best exposed sections of the Shus-
wap series is that exhibited as a great monocline
from Canoe point, along the western shore of
the lake, to Cinnemousun narrows, 23 kilometres
distant. Green schist and massive limestones,
corresponding to the youngest recognized mem-
bers of the Shuswap series, are found near the
narrows and at the top of this northerly-
dipping monocline. The rocks on the opposite
shore of the lake, north of Sicamous, are
largely orthogneisses and have attitudes usually
quite different from those of the monoclinal
section. The valley of this part of the main
lake therefore seems to be located on a fault
with downthrow on the west.

From the limestone band just west of Sicamous
to the 56th mile-post the line crosses the Salmon
Arm schists injected with many sills and dykes
of orthogneiss, pegmatite and aplite.

At 56-2 miles (90 -4 km.) a large rock-cutting
shows a coarse porphyritic syenite, which crops
out again at the southwestern base of Bastion
mountain nearly due west, across the lake.
This rock appears to be a peripheral phase of

227

Miles and a batholith extending southward and westward

Kilometres. & , .

for many kilometres and northward a short
71 m. distance beyond Tappen station. The central
114-2 km. and greater part of the batholithic mass is com-
posed of biotite granite. Like the syenitic phase,
it is massive, relatively little crushed, and lacking
the multitude of pegmatitic injections so charac-
teristic of the Shuswap orthogneisses. This
batholith thus seems to be of post-Shuswap
date and it is tentatively referred to the late
Jurassic period of granitic intrusion.

The bold bluff of Bastion mountain north of
the Arm is composed of the Sicamous lime-
stone dipping 280 to the N.W. The limestone
forms a continuous band along the southern
face of the mountain to the shore of the main
lake north of Canoe point, and 15 kilometres
from the bluff overlooking Tappen.

Looking southward from Salmon Arm, a
thick cap of Tertiary lava (basalt and augite
andesite of the Kamloops groups), unconform-
ably overlying the granite, is seen in Mt. Ida.
This is the first of many similar remnants of
these Oligocene (?) volcanics to be encountered
in the railway belt. (See page 148.)

As the train leaves Tappen and climbs the
grade to Notch Hill station, the dark Bastion
schists overlying the Sicamous limestone may
be observed occasionally across the valley.

8o-i m. Notch Hill Station— Alt. 1,685 ft. (513 m.).

128-9 km. At this point the line is crossing greenstones
and chloritic schists, representing the volcanic
Adams Lake member of the Shuswap series
(page 124) or else much metamorphosed 'ntrus-
ives of the same general epoch. The Blind Bay
valley is floored with the Sicamous limestone
presumably repeated here by a strike-fault.
The ridge southwest of Notch Hill is com-
posed of a second outlier of the Oligocene ( ?)
87-8 m. lava-field. Near Squilax station the railway

144-5 km. touches the unconformity between this volcanic
cap and the Shuswap green schist formation.
Here the growing delta of Adams river draining

228

Smelts. tne l°n£ Adams lake can be seen to separate
the main Shuswap lake from Little Shuswap lake.

The smaller lake basin has been eroded in
Shuswap orthogneiss with the form and relations
of a large irregular laccolith cutting the Chase
quartzite and coarse mica schists of the same
habit as that characterizing the Salmon Arm
schists thermally metamorphosed. The lacco-
lith is itself gneissic. Its planes of schistosity,
like its contacts and the invaded sediments,
dip 55-600 to the N.N.W. The E.N.E. end
of the body is near Squilax; the W.S.W. end
appears on the ridge across the river from
Shuswap station. Where observed, the upper
contact of the laccolith is made with the Salmon
Arm(?) schists or with (intrusive?) greenstone
of Shuswap age. The schists below the lower
main contact are heavily injected with ortho-
91-9 m. gneiss sills, and at Stormont siding the massive
147-9 km. orthogneiss cross-cuts the sediments as a very
broad dyke extending southeastwardly through
the mountain. This 'dyke' may represent the
main feeder of the laccolith.

Between Chase (94-0 m. — 151-3 km.) and
Shuswap station (95-9 m. — 154-3 km.), the
line nearly parallels the strike of the coarse
Salmon Arm schists. The cliffs east of Shuswap
are composed of the underlying, massive
Chase quartzite dipping 50° to the N.N.W.
(See page 123).

A short distance beyond this station the
sediments are truncated by a homogeneous
granite, little strained and with other character-
istics of the post-Paleozoic (late Jurassic) batho-
liths. With its abrupt appearance the section
leaves the Shuswap terrane.

Terraces become more and more prominent
features in the valley floor. Their material is
remarkably fine-textured, homogenous silt, show-
ing distinct, even, bedding. As Dawson recog-
nized long ago, it is clearly a lacustrine deposit
and dates from the late Pleistocene. Since the
silt was not deposited in the basin of Little
Shuswap lake, it is most probable that that

230

Kilometres basin was closed by a thick valley glacier at the
time of silt deposition. The valley was similarly
dammed by a large, local glacier entering from
the valley of the North Thompson. Through-
out the distance from Shuswap nearly to
Kamloops — 50 kilometres — the valley of the
South Thompson was thus laked, and fine,
white silt was accumulated to depths greater
than 120 metres.

Nine kilometres beyond Shuswap station,
the western contact of the granite is reached.
It is here intrusive into the rocks of the Nicola
series, in which the valley of the South Thompson
river is sunk for a distance of 19 kilometres
(102 mis. to 118 mis.)

The first rocks of this series to be crossed
constitute a thick well-stratified body of hard
sandstones and fine-grained strata shown to be
in part bedded volcanic ash, but probably in
part true argillites. Subordinate volcanic brec-
cias of basic composition are interbedded.
The whole forms the youngest local phase of
the Nicola series conformably overlying the
massive lavas of the Triassic, and is itself either
upper Triassic or Jurassic in age. The dips
here range from 6o° to 8o° to the east, indicating
an apparent thickness of more than 2,000 metres
for this stratified member.
104 m. Just beyond Pritchard siding is its (lower)
168.6 km. contact with the very massive lavas of the
Triassic Nicola series (see p. 145). These can
be well seen in dark coloured bluffs across the
river. Their structure is extremely difficult
to decipher. Pyroclastic beds are rare; thick
flows (and sills?) of basaltic lava are dominant.
Wherever the dips can be observed they are
steep, generally 500 to 900, with strikes ranging
from N.-S. to N.W.-S.E.

To right and left the distant summits are
capped by Tertiary basaltic lavas (Kamloops
group) with associated fresh-water sandstones.
These have low dips and overlie the more
massive, more deformed, and more altered
Triassic volcanics unconformably.

231

Miles and
Kilometres.

m-9 m. Ducks station — Alt. i ,146 ft. (349 m.). At
180 • 1 km. this point the Nicola rocks are specially well seen,
across the river. Three kilometres to the south-
east, the Tertiary lavas are now dipping at
angles varying from 450 to 900, indicating the
local vigour of the last orogenic deformation
(late Miocene) in British Columbia.

At and beyond Ducks station, the silt
terraces are very conspicuous.

At the 1 1 8th mile-post, nine kilometres
beyond Ducks, the Triassic series can be seen
north of the river, resting on the Carboniferous
(Pennsylvanian) limestone, the light gray
colour of the latter contrasting well with the
deep tint of the Nicola lavas. The relation
is that of unconformity, since the lavas are under-
lain by a basal conglomerate containing chert
pebbles derived from the limestone. The con-
glomerate and the plane of unconformity dip
east at an average angle of about 500, The
limestone has a variable attitude but also dips
at a high angle to the eastward. The agreement
seems to show that the pre-Triassic deforma-
tion of the Carboniferous strata was not
severe.

This is one of the best exposed contacts
between these two great series yet found in
British Columbia.

Continuing to Kamloops, the route crosses the
Carboniferous rocks. (See p. 144). The dark-
coloured ledges are chiefly composed of cherty
quartzites and altered argillites, but some basic
volcanic ash and coarser pyroclastic material is
also interbedded. At intervals, light gray
vertical bands represent as many occurrences of
older fossiliferous Pennsylvanian limestone.
The general structure north of the river, through
to the North Thompson river, is the mono-
clinal. The strike averages N. 35-400 W.; the
dip, 75-800 to the N.E. Yet there are a few
local reversals of the always steep dip, and it is
likely that the total thickness calculated from
35069— 9A

232

saometres tne generauzed monocline is deceptively great.

Nevertheless, a minimum thickness of 2500
metres of Pennsylvanian beds seems to be
represented. It is improbable that pre-Penn-
sylvanian formations occur in this section.
122- 1 m. Kamloops — Alt. 1,151 ft. (351 m.) — is another
207 -8 km. important distributing centre for the interior
trade of the province. Its location was deter-
mined by the confluence of the South Thompson
and North Thompson valleys; the one followed
by the existing Canadian Pacific Railway, the
other now witnessing the completion of a second
transcontinental line (Canadian Northern Rail-
way). Since leaving Little Shuswap lake the
country has become rapidly drier and Kamloops
is the centre of a scattered farming and grazing
community largely dependent on irrigation
facilities.

Beyond Kamloops the mile-posts begin a
new sequence of numbers; distances will be
stated accordingly.

Just outside the western limit of the town
the railway crosses a band of massive traps
referable to the Nicola series. These are uncon-
formably overlain by low-dipping Tertiary
(Oligocene?) lava flows and tuffs, containing
the fossiliferous Tranquille sandstones and
shales (seep. 149). These can be seen on both
sides of the river delta now growing rapidly
into Kamloops lake through the activity of
the silt-laden river. The Tertiary sediments
8 - o m. may be seen, on the left, at Tranquille Siding.
12-8 km. Just beyond that point the line skirts the
long cliff called "Cherry Bluff." The massive
rock composing it is a sheared and greatly
altered mass of variable, dioritic to monzonitic
and even gabbroid nature. The body is 8 kilo-
metres long and 4-5 kilometres in maximum
width. The lake lies in its major axis and the
replica of Cherry Bluff is to be seen in "Battle
Bluff" across the water. The granular rock is
clearly intrusive into the Nicola traps, which form
part of its roof both north and south of the
lake. The relation to the Tertiary series is

233

KUomSres not so °bvious. The Oligocene (?) lavas and
sediments dip away from the intrusive on all
sides, as if the intrusive were a partially un-
roofed laccolith of later Tertiary date of intru-
sion. One difficulty standing in the way of
full belief in this hypothesis is the advanced
shearing and alteration of the intrusive; a
similar condition is extremely rare in the
post-Oligocene intrusives of the Cordillera.
According to a second interpretation the lacco-
lith dates from the Triassic, representing a
late phase in the eruptivity of that period.
On this view the shearing of the intrusive and
the deformation of the Tertiary rocks would
be explained by a post-Oligocene, orogenic
doming of the whole complex of solid rocks.

14-6 m. Cherry Creek station. — Alt. 1,134 ft. (346 m.).

23-4 km. Here the southeastern contact of the great
intrusive is crossed and the line then runs
continuously over the Triassic (Nicola) traps
(with fossiliferous interbeds of limestone) to
Savona (25-3 m. — 40-7 km.).
19-7 m. At Munro Siding the " Painted Bluffs," east
32 km. of Copper creek across the lake, are in full view.

These are composed of brilliantly coloured Ter-
tiary volcanic rocks. The Tranquille tuff beds
which underlie the basaltic lavas of the Kamloops
group, vary from pale buff or dull green to dark
red, brown or gray in colour, and are largely al-
tered. Plant and fish remains are found in these
beds which place them provisionally in the Oligo-
cene. The sequence of the lavas and pyroclastics
on the north side of the lake is almost identical
with that exposed on Savona mountain on the
south side. It is thought that the sections are
on the limbs of a broad anticlinal dome since
bevelled off during a Pliocene erosion cycle.
The surface resulting is well preserved on both
Hardy and Savona mountains.

West of Copper creek, on the hillside may be
seen the sites of cinnabar mines which have
produced 7,000 lbs. (3,175 kg.) of mercury.
The cinnabar is associated with small quanti-
ties of stibnite and has a calcite-quartz gangue.
35069— giA

234

The ore is found in irregular veins traversing
an altered, now dolomitic greenstone containing
pyroxene and olivine.

The silts forming occasional benches on the
shores of Kamloops lake are often seen to have
been crumpled by overriding ice which occupied
the valley during a tempoiary increase of
glacial activity in the late Pleistocene.

Metres

O 5 lO 15 20

Section illustrating great crumpling of Glacial silts by advancing ice sheet
which deposited typical till on the silts. Locality 3 . 5 km. west of Cherry
Creek station.

WESTERN PART OF THE BELT OF INTERIOR
PLATEAUS.

( SAVON A TO LYTTOX.)
BY

Charles W. Drysdale.

ESSENTIAL GEOLOGY.
Introduction.

That portion of the British Columbia Cordillera which
lies between the Columbia Mountain system on the east
and the Coast range on the west, is known as the Belt
of Interior Plateaus. It is with the section between Kam-
loops lake and Lytton, along the course of the Thompson
river which traverses this belt, that the following outline
of geology deals.

The district was first examined geologically in 1877 by
G. M. Dawson [1] and again by him in a more detailed

235

manner during the summers of 1888, 1889, 1890. The
results of his work are contained in the Report on the
Kamloops Map Sheet [4].

Physiography.

As viewed from the wide, open valley of Thompson
river, the Kamloops district presents a hilly and even
mountainous relief, the bordering summits rising from
4,000 to 5,000 feet (1,200 to 1,500 m.) above the level of
the river. A broad summit view, however, explains why
it is included among the Interior Plateaus of British
Columbia, fcr from about the 4,000-foot (1,200 m.) level,
there stretches as far as the eye can see a series of gently
undulating and plateau-like upland surfaces. Within
the upland, the younger valleys appear to be deeply
entrenched.

Both the annual and daily range of temperature is great.
On account of the very slight rainfall, the region is common-
ly known as the "Dry Belt of British Columbia."

Where irrigated, the semi-arid land of the valleys,
commonly covered with sage brush, cactus, scattered
yellow pine, and thickets of poplar, is very productive
of fruits and vegetables. The grassy "park country" of
the upland affords good grazing for cattle, and a supply
of timber for the ranches.

For the explanation of relief in the district at least
three cycles of erosion must be considered: one in Cre-
taceous; one in pre-Miocene; and the latest in Pliocene
time. It is to the Pliocene erosion cycle that the present
upland topography chiefly owes its development.

The facts upon which the above tentative conclusions
are based are as follows: —

1. Early Tertiary (Eocene ?) conglomerates rest directly
upon the upper Jurassic batholith south of Walhachin.
The conglomerate is largely composed of well water-worn
boulders of granite and Paleozoic metamorphics. As
granite batholiths consolidate under considerable thick-
nesses of superincumbent material, such conditions would
necessitate the removal by erosion of the entire cover
from the batholith. A great thickness of rock must,
then, have been removed during the Cretaceous period.

2. The absence of Upper Cretaceous rocks in the dis-
trict, and the entire absence of Cretaceous rocks east of

236

Ashcroft would imply continental conditions and con-
sequent erosion during at least late Cretaceous time.

3. South of Kamloops lake at an elevation of about
2,000 feet (610 m.) an extensive flat is underlain by
Jura-Triassic rocks, and entrenched by an early
Tertiary river valley. The old river valley is filled with
Coldwater conglomerate, sandstone, and shale dipping
at low angles. The rocks of this formation form prominent
strike ridges which rise high above the flat referred to,
and form, at the contact, a topographic unconformity.
The flat is a conspicuous topographic feature, and is
thought to represent a remnant of an old uplifted Cre-
taceous erosion surface since modified by Glacial action.
Here, through favourable tectonic conditions, a portion
of the Cretaceous erosion surface has been preserved to
the present time and dominates the topography.

4. The next erosion cycle provisionally referred to pre-
Miocene and post-Eocene time, is evidenced by a marked
unconformity between early Tertiary formations and lower
Miocene (?) volcanics. Near Ashcroft, as elsewhere through-
out the Belt of Interior Plateaus, the early Tertiary form-
ations are strongly uptilted, and they have been apparently
subjected to crustal disturbances prior to the later vulcan-
ism. Such orogenic movement would naturally inaugurate
a new cycle of erosion which probably removed vast
quantities of the loose continental deposits of early
Tertiary age.

5. The third and most important erosion cycle which
is thought to have largely developed the present upland
topography, continued into the Pliocene.

The Miocene (or Oligocene?) lavas which cap the hills in
so many widely scattered localities throughout the Belt
of Interior Plateaus, have been warped to form broad
synclinal basins and anticlinal domes. The anticlinal domes
have since been removed through denuding agencies. It
is found that the present late mature upland (locally a
peneplain) truncates or bevels the tilted lavas for great
distances. The upland erosion surface in this district may
be correlated with one found by the writer during the
summer of 191 1 in the Franklin Mining district in the
Columbia Mountain system. There it truncates the
Midway Volcanic group of trachytes and alkalic basalts
referred to the Miocene period.

237

GLACIATION.

The deep pre-Glacial Thompson valley contains a great
thickness of fluvio-glacial material now in process of being
excavated. Sections of such glacial and interglacial debris
exposed by the river and railroad, aid considerably in the
determination of the Pleistocene history of the province.

The region of Interior Plateaus was, during the Pleisto-
cene, covered by the Cordilleran ice cap, whose direction
of flow here, as shown by striae, was about S. 350 E.
The upland slopes are thickly mantled with morainic
drift and erratics left stranded by the retreating ice sheet.
On the other hand, the contemporaneous boulder clay
deposited in the valleys below, has since been largely re-
moved by the advance of valley glaciers.

With its waning, the Cordilleran continental glacier
gave place to alpine, cirque, and valley glaciers. Much
englacial and superglacial material was deposited and
reworked by water. The older gravels, sands, and strati-
fied clay silts, capped by boulder clay, are referable to
this period of alluviation, contemporaneous with the first
period of valley glaciation.

The valley ice slowly retreated until the time of the
maximum extension of the Keewatin ice sheet on the
east, when the second period of valley glaciation in the
Cordilleran belt probably took place. This advance
of the ice removed much of the older morainic and outwash
materials, deeply eroded the valleys, and heaped up
lateral and terminal moraines. The high-level esker-
like ridges of the valley sides probably represent the work
of streams at the borders of the ice. The streams draining
the ice front carried down and deposited large quantities
of land waste in the form of a deep alluvial fill.

With the melting and recession following the maximum
advance of the second period of valley glaciation, large
amounts of drift materials were set free. Great thick-
nesses of silts were then deposited in the tranquil waters
of lakes. These lakes were formed on the main valley floors,
either dammed by powerful local glaciers entering from the
sides, or perhaps locally basined at a time of special sub-
sidence yet greater than that recorded for the late Pleisto-
cene along the Pacific shore. At the mouths of tributary
creeks alluvial fans composed of cross-bedded gravels

238

and sands, were laid down under water and are intercalated
in the White Silt formation.

Following the complete withdrawal of the ice from this
portion of the Cordillera, the denuded region of former
vigorous glaciation would supply but little rock waste
to the streams. With the reduction in waste supply and
but a moderate reduction in volume, the streams here
deeply degraded the earlier accumulations. Degrada-
tion was probably further aided by regional uplift which
invigorated the streams. Terraces due to the normal
lateral swinging of the river, as well as to later minor
stages of alluviation and degradation dependent upon
climatic change, are present throughout the Thompson
valley. An old river bed is found to lie persistently in
sharp contact with the White Silt for many miles. It
is represented by a coarse gravel with boulders over-
lapping each other in the direction of flow. It is generally
found directly beneath the surface silt and sand of the
terrace on the bed-rock side of the valley.

The district between the east end of Kamloops lake
and Lytton may be divided into three distinct sections.
The eastern section covers Kamloops lake, where the
Thompson valley appears to have been glacially deepened
to a great extent The result is that the tributary valleys
bear hanging relationships to the main valley. There
are well developed alluvial fans and cones chiefly of sub-
aqueous origin, at the mouths of the tributary creeks.
The main valley itself is comparatively free from glacial
outwash material.

The central section extends from the west end of Kam-
loops lake (26 miles — 42 km.) to Thompson Siding (85-3
miles — 158km.). It is characterized by a great depth of
Glacial valley-train material, beautifully terraced by the
meandering Thompson river. The deeply incised river,
however, has only in a few places reached the rock floor
of the old pre-Glacial valley.

The western portion of the central section from Toketic
to Thompson Siding, owing both to the increased gradient
of the river and the narrowness of the valley, contains
only narrow terrace lands, and a comparatively small
development of the White Silt formation.

The western section, from Thompson Siding to Lytton
(9-48 miles — 153 km.) — the Thompson Canyon proper — ,
displays a very mountainous appearance in bold contrast

239

to the eastern belt. Here the Thompson river has cut
completely through the outwash valley-train and has
deeply incised itself within the pre-Glacial floor of bed-
rock, forming a deep canyon. The canyon bottom con-
tains many huge blocks of rock that have tumbled from
above, and are now in process of being broken up and
carried downstream by the turbulent river.

STRATIGRAPHY.

The bed-rock geology has chiefly to do with formations
of Mesozoic and Tertiary age.

The following is a table of formations in descending
order : —

Approximate thickness (after
Dawson).

Pleistocene and Recent.

Superficial deposits.
Glacial till, gravel,
clay and silt.

sand,

Lower

Miocene (?) *

Feet.
3,000

I ,000

Eocene (?) 5,ooo

Lower Cretaceous. 5,ooo

Jura-Cretaceous .

5,000

Metres.

914 Kamloops Volcanic group;

basalt, agglomerate, breccia,

trachyte.
305 Tranquille beds;

fine-grained tuffs.

Coldwater group;
1,524 conglomerate, sandstone,

Ashcroft rhyolite porphyry.

1,524 Queen Charlotte Islands forma-
tion (?); shales, conglomer-
ate and sandstone.

1,524 Spence's Bridge Volcanic group;

andesitic and liparitic lavas,
tuffs, and arkoses.

Upper Jurassic Granitic intrusives; batholiths,

stocks, and tongues.

Jurassic-Triassic. . 10,000 3,048 Nicola formation; greenstone,

impure quartzite, argillite,
limestone, agglomerate and
tuff.

Carboniferous.

9,500 2,896 Cache Creek formation; cherty
quartzite, greenstone and
marble.

* Dr. R. A. Daly refers these rocks tentatively to the Oligocene system. See page 149.

240

The Cache Creek formation consists of very badly
metamorphosed sedimentary and eruptive material belong-
ing to the Main Pacific geosynclinal. The commonest
rock member is a cherty quartzite traversed by veinlets
of quartz. Dark massive argillites and contemporaneous
eruptives are of more local occurrence. Younger than the
above rocks, but in many places intimately interfolded
with them, is a limestone formation {Marble Canyon
limestone) now recrystallized to marble. Large fcramini-
fers known as Loftusia columbiana and the diagnostic
Carboniferous fossil Fusulina are found in the Marble
Canyon limestone. Much of the gold found in the placer
workings along the Thompson and Fraser rivers may have
been derived from the Cache Creek quartz veins. On
account of the unfavourable character of the outcrops in
the railway section it has here proved impossible to ascer-
tain the full thickness. The estimate of Dawson is noted
in the foregoing table.

The Nicola formation is well exposed in the Thompson
valley and consists of greenstones (altered eruptives of both
flow and fragmental type) intercalated with beds of
argillite and limestone. Crinoid remains, pelecypods,
terebratulas and pectens of several species are found in the
calcareous members of the formation. These fossils
place the series in the Triassic, grading up into the lower
Jurassic. G. M. Dawson estimated that the thickness of
the Nicola formation ranges from 10,000 to 15,000 feet.
The agglomerates and porphyrites of this formation, by
their much more metamorphosed and massive character,
are readily distinguished from those of the Tertiary.

The batholiths, stocks and tongues which occur in the
district are referred to the upper Jurassic. They are made
up of granular intrusive rocks varying from granite to
granodiorite and diorite, and are all subalkalic in composi-
tion.

During the Lower Cretaceous or late Jurassic, volcanic
eruptions broke forth along the east front of the Coast
range resulting in the accumulation of over 5,000 feet
(1500 m.) of acidic and intermediate lavas and tuffs — the
Spence's Bridge Volcanic group. This group has heretofore
been referred to the Miocene (Lower Volcanic group of
Dawson) but recently discovered plant, structural and
physiographic evidence place the group in the Lower
Cretaceous or late Jurassic.

241

Like the Coldwater group, the rocks of the Spence's
Bridge Volcanic group have been much broken and
metamorphosed prior to the outpouring of the Mid-Ter-
tiary lavas.

In the vicinity of Ashcroft, carbonaceous shales, sand-
stones, and conglomerates occupy a local synclinorium
striking nearly north and south. The western portion of
the inlier is more steeply inclined and folded than the
eastern, where the rocks appear to overlap flatly the Jura-
Trias formation. This formation has been referred on
lithological grounds to the Lower Cretaceous, and correlated
with the Queen Charlotte Islands formation on the Pacific
Coast.

Another inlier of Lower Cretaceous rocks occurs near the
mouth of Botanie creek about two miles (3-2 km.) above
Lytton. There, however, the dark shales, grey sandstones
and conglomerates are much disturbed and slickensided.

The (probably Eocene) Coldwater group consists of con-
tinental sediments which include coarse fluviatile conglomer-
ates, sandstones, and shale, with occasional coal. The
deposits occupy erosion troughs cut into an older Cre-
taceous erosion surface. They have been locally upturned
and eroded before the eruption of the younger Tertiary
volcanics.

The Kamloops Volcanic group consists of basalts (both
amygdaloidal and vesicular types), agglomerates and
breccias, with smaller quantities of younger mica trachytes
and various porphyrites. In the railway section the forma-
tion has an average thickness of about 2,500 feet (760 m.).

These lavas have a wide distribution through the Belt
of Interior Plateaus, and as a rule lie almost horizontal.
In places, however, they have been broadly folded into
synclinal basins and anticlinal domes. The latter have
been eroded away leaving the synclines at present exposed
chiefly on the hill tops. Quite locally, but not within
the limits of this section, these lavas have been tilted to
vertical or nearly vertical positions.

Near the base of the Kamloops volcanics, a considerable
thickness of evenly bedded tuffs occur — the Tranquille beds
of G. M. Dawson. They are, as a rule, pale in colour and
contain plant remains, thin coal seams, and occasionally
fossil fish of lower Miocene or Oligocene' age.

Deposits of Pleistocene age are very plentiful, and consist
of Glacial till, gravels, sands, clays and silts.

242

SUMMARY HISTORY.

There is no record in the Kamloops district of pre-
Carboniferous formations, and the area was probably
subject to erosion during the early Paleozoic. The Main
Pacific Geosyncline was initiated probably in Carboniferous
time, and the Cache Creek formations laid down in an
eastwardly transgressing sea. Sedimentation was interrupted
at times by vulcanism.

The close of the Paleozoic was marked by deformation
and a return to continental conditions. Submergence
in Triassic time brought a return of marine conditions,
with the deposition of argillaceous and siliceous muds and
limestones, accompanied by volcanic activity on a grand
scale. Vulcanism ceased in Lower Jurassic time and
sedimentation continued with the deposition of arenaceous
limestones rich in marine fauna.

Orogenic movements in the upper Jurassic were either
preceded or followed by intrusions of granitic batholiths,
stocks and tongues as well as volcanic activity along the
east front of the Coast range (Spence's Bridge Volcanic
group).

During the Lower Cretaceous marine conditions were
locally restored in geosynclinal downwarps, which received
the detritus washed in from the lands, especially from that
on the east. Later an emergence took place and these
areas seem to have shared in the erosion of the later Cre-
taceous. Therewith much of the cover of the Coast
Range batholith was removed and the Interior Plateau
country was brought down nearly to base level.

During the Laramide revolution the thick Mesozoic and
older formatioms were greatly uplifted, locally folded and
overthrust from west to east. The Coast Range and
Columbia Mountain systems were loci of maximum uplift,
and may have supported local alpine glaciers.

The Laramide revolution invigorated the drainage and
made the rivers deeply entrench themselves within the
older Cretaceous erosion surface. The Coldwater group
conglomerates, sandstones and shales were then deposited
in the erosion troughs and basins.

Local volcanic vents supplied rhyolitic lavas and acidic
tuffs which are frequently associated with the early
Tertiary formations. During the Oligocene which con-
tinued the erosive work of the Eocene, crusta

243

disturbances took place, uplifting and deforming the early
Tertiary formations. This orogenic movement brought
about vigorous erosion, and a great volume of the early
Tertiary rocks was swept away. Volcanic activity broke
forth on a grand scale in the early Miocene,* and great
thicknesses of basaltic lavas, agglomerates, breccias and
tuffs (Kamloops volcanics) spread, over large areas. Crustal
warping took place probably in the late Miocene and
threw the flat-lying Kamloops volcanics in places into
broad anticlinal domes and synclinal basins. Con-
tinued erosion in the Pliocene brought the whole belt to a
stage of late maturity and local peneplanation. Wide
and shallow, trough-like valleys were formed. At the
close of the Pliocene or beginning of the Pleistocene, regional
uplift took place, and the major streams deeply incised
themselves within the uplifted erosion surface. During
the Pleistocene, the Cordilleran ice-sheet advanced and
retreated, leaving much drift. At least two distinct
periods of valley glaciation and alluviation followed the
retreat of the ice cap. The disappearance of glacier ice
from the valleys increased the eroding activity of the
streams which began the dissection of the alluvial gravels,
sands and silts. This process of dissection, still active,
was probably further aided by regional uplift.

* Dr. R. A. Daly prefers to give weight to the available paleontological evidence
which tends to assign the Kamloops and Tranquille formations to the Oligocene.
The time of their warping is accordingly to be described as the interval between the
late Oligocene and the Pliocene period; and their extensive denudation is ascribed
to work performed through practically all of post-Oligocene time.

ANNOTATED GUIDE.

(Savona to Lytton.)

Miles and
Kilometres.

25-3 m. Savona — Altitude 1,158 ft. (352-9 m.). On
Savona mountain which may be seen to the
40-7 km. south of the town, occurs a thick section of the
(from Kamloops volcanic group.

Kamloops) In descending order it is approximately as
follows : —

244

Coarse agglomerate on summit

Reddish, black and greenish black lavas chiefly
vesicular and amygdaloidal

900 ft. 274-3 m.

200 ft. 60-9 m.

Agglomerates, varying to ropy lavas

Grey, black, and red lavas, some vesicular, in
places slightly agglomeratic

600 ft. 182-8 m.

800 ft. 243-8 m.

Total

2,500 ft. 761 -8 m.

Miles and
Kilometres.

32-1 m.

Three miles west of Savona, Kamloops lake
ends at the broad well-terraced delta of the
turbulent Deadman river. The growth of the
delta has probably raised the level of Kamloops

Thompson river here has been forced to the
south and bed-rock side of the valley, and from
the railroad may be seen the markedly cross-
bedded outwash gravels 2nd silts exposed in
the high banks across the river.

The valley of Deadman creek with its glacially
steepened walls, may be seen extending for
more than ten miles (16 km.) northward, where
it merges into the lava-capped upland plateau.

The river west of Deadman creek, follows a
tortuous course through the thick alluvial
valley-fill. Near the 30th mile-post the river
makes a prominent horseshoe bend now cut
off to form an island and slough across which
the Canadian Northern Railway Company are
building their line.

Walhachin — Altitude 1,252 ft. (381 -6m.).
Walhachin — the centre of an extensive fruit
growing district — is situated on the brink of one
of the principal fiuvio-glacial terraces of the
region. The water for irrigation purposes is
flumed from Deadman river. The Thompson
valley is very wide here, and the river follows a
meandering course within it. The result has
been a splendid development of broad, gently
sloping terraces preserving old meanders and
cusps formed by the river at higher levels.
Coarse gravel overlying silt, seen from the

ica.1 Survey, Canada,

Route map between Ducks and Lytton

Miles

O 5 IO 15 £

Kilometres

T4-I

Legend

Tertiary

\ [ T4- Upper Volcanic group
chiefly basalts

^ T3 Tranqui/le beds

<b f T2 Co Id watt

-group

Tl Acid,

ic lavas

K,J,TI Mesozoic

KT Cretaceous

conglomerate,sandstone, shale

J Jurassic

limestone j quarbzibe

"T? Triassic

greenstone fa/ 'bered erupt/ res), limestone

Post-Jurassic

granitic rocks

Carboniferous

cherby quartzi te, marble, schisb

245

aiometres train at many places, represents an old river
channel.

A broad belt of Coldwater conglomerate,
sandstone, and shale outcrops about one mile
(i-6 km.) south of the railroad. These sedi-
ments represent an old Eocene river course,
later uplifted, eroded and protected from further
erosion by remnants of younger lava flows.

The train after leaving the Walhachin terraces,
winds around points of Triassic rocks and
through alluvial fans built up by tributary
creeks, until it reaches the 37th mile-post,
where a granitic boss is encountered. The
granodiorite extends across the river east of
Eight Mile creek, and, a couple of miles north,
disappears under the lava cap of the Kamloops
volcanic group.
38-4 m. Semlin — Semlin is a railroad siding named
61-7 km. from the broad, hanging Semlin valley which
joins the main Thompson valley at this point.
The Semlin valley is probably an old course of
Bonaparte creek.

A short distance west of Semlin station, the
railroad cuts through the basal portion of a
syncline in the Kamloops volcanics. The
syncline, which is a continuation of the Savona
mountain remnant, extends northward across
the river where it widens out into a broad
synclinal belt capping the hill tops. The se-
quence of the rocks as exposed in the rock cuts,
shows lavas of trachytic habit, succeeded
above by basaltic lava with columnar jointing.
The basalt passes into a dense bluish-black
phase with pronounced ball-and-socket jointing.
The lava passes upward into grayish tuffs and
coarse agglomerates containing fragments of
basalt. The upland in this vicinity is a pene-
plain which truncates the slightly tilted Kam-
loops volcanics. One mile (i-6 km.) west of
Semlin, the railroad emerges from the lava
syncline and cuts through great thicknesses of
alluvial silts, gravels and till. The clay silt is
quite consolidated and stands in vertical cliffs
forming in many places weird "hoodoos".

246

KUomeS-es ^n one section there is exposed to view about
1 50 feet (45 • 7 m.) of clay silt overlain by bouldery
till. The alluvium here is underlain by a
granodiorite batholith capped by a continuation
of the same series of Kamloops lavas.

The contact between the granodiorite batho-
lith and the Jura-Triassic (Nicola) is near
the 43rd mile-post at a narrow part of the
valley. The Triassic limestones and intercalated
sheets of irruptive rock stand out prominently
across the river on the southeast flank of Rattle-
snake hill, where the series dips about 450 to the
northwest.

The Nicola formation is overlapped from the
west by Cretaceous conglomerate, shale, and
sandstone — a formation which is encountered
first at the mouth of Barnes creek, where the
Thompson valley broadens out, preparatory to
taking a sharp southward bend in its course.
Here the river has been forced back upon the
delta of Bonaparte creek by the building out of
the Barnes Creek delta. The river has cut deep-
ly northward into the fluvio-glacial silts and
gravels west of Rattlesnake hill which stand out
in prominent cliffs about 300 feet (91 m.) high.
In one place, the stratified clay silts are seen
contorted and folded into a synclinal trough
which is filled by a younger and more sandy silt.
The younger silt was probably carried down and
deposited subaqueously by Bonaparte creek in
what was then a lake. The silts are believed to
be of two distinct periods of alluviation contem-
poraneous with two periods of valley glaciation.
The silts may be traced southwestwardly to-
ward the mouth of Bonaparte creek, where
boulder clay is found overlying the cross-
bedded gravels, sands and silts of the first period
of alluviation. The boulder clay is in turn
capped by a coarse river bed deposit with a
thin layer of silty soil on the surface of the
terrace.

47-2 m. Ashcroft. — Altitude 996 ft. (303.5 m.).
75- 9km. Ashcroft, "the gateway to the north country",
is situated in a wide, level tract of valley land

35069— I OA

248

KUomrtres underlain by the readily eroded Cretaceous
rocks. The terraced alluvial filling of the
valley, where irrigated, is very fertile and
produces large crops of potatoes and other
vegetables.

From the train one sees terraced out-
wash Glacial materials skirting the hills of
Cretaceous rock which are for the most part
capped by Tertiary lavas. The lavas of the
mesa-like hills are vesicular and amygdaloidal
basalts similar to those at Savona mountain.
The main type is a dense, bluish-black basalt
showing splendid ball-and-socket, as well as
columnar jointing. On the hill seen from the
railroad a few miles to the southeast of Ash-
croft, this basalt is found capping unconformably
a remnant of rhyolitic lava of probably Eocene
age.

The topography in this portion of the Thomp-
son valley on account of the semi-arid nature of
the climate, approaches the 'bad land' type.
The hillsides are dissected by numerous small
gullies and ravines as a result of intermittent
but violent rainfall.

One half mile south of the 50th mile-post,
after passing through the great landslide of
October, 1881, a gravel cut shows boulder clay of
the first period of valley glaciation, which here
underlies the clay silt and gravels deposited
during a later alluviation stage of the same
period. The railroad cuts through fissile Lower
Cretaceous argillites dipping steeply to the
west. The rocks at the western border of the
Ashcroft Cretaceous are more folded and dis-
turbed than those at the eastern border where
they appear to overlap the Jura-Trias rocks.
The total thickness of the formation is about
5,000 feet (1524 m.). A coarse basal conglom-
erate and grit member of the Lower Creta-
ceous is exposed in the rock cut immediately
north of the Black Canyon tunnel.
52-5 m. Black Canyon — The Thompson river here
84-4 km. has incised itself, not only through a great
thickness of alluvium, but has also cut more

249

iaiomSres t^ian 200 ^eet (6° m') ^eep *nto t^ie bed-rock
itself. This bed-rock is black Cretaceous shale
and sandstone. On account of the sombre
appearance of the rocks, the gorge is known as
the Black Canyon.

To the east of the southern portal of the tun-
nel may be seen typical mud-slide ground. The
ground creeps and forms gaping fissures. Where
material has broken away to form landslides,
steep bluffs remain. These slides and creep of
the ground have caused the railroads much
trouble and expense.

About two miles (3-2 km.) below the Black
Canyon, the Cretaceous conglomerate (largely
granitic) grades down, within a few feet, into
an angular breccia, which rests unconformably
upon the Nicola rocks.

54 -6 m. Basque — Opposite Basque siding the Cre-
87-8 km. taceous ends, and the underlying Paleozoics
(Cache Creek formation) appear for the first
time. A few miles west of the river may be
seen Red hill, named on account of the highly
coloured character of the rocks which compose
it. The pyritic cherts and sheared rhyolites of
the Cache Creek group have been weathered so
as to form red outcrops.

A section of Jura-Trias rocks, intruded by
tongues from the underlying granodiorite bath-
olith, may be seen a few miles below Basque.

On nearing Spatsum one may see the west
flank of a prominent block mountain composed
of Jura-Trias limestones dipping and striking
conformably with the slope of the hill. The
more resistant, massive Jura-Trias rocks, in-
stead of yielding to orogenic stresses by folding
and mashing (like the Cretaceous shales and
sandstones), yielded rather by bodily over-
thrust from the west upon a broad underlying
granitic batholith. Clinging to the batholith is
a rim of chert due to the contact metamor-
phism at the time of batholithic intrusion.
60 -8 m. Spatsum — Altitude 854 feet (260-2 m.). On
97 -8 km. the opposite side of the river from Spatsum,
35069— io^a

251

Kilometres gypsum and china clay may be seen in crumb-
ling outcrops of red, yellow and white. The
highly coloured decomposed material is almost
devoid of vegetation.

The Cache Creek formation crosses the river
at Spatsum, and extends southward to Toketic,
where black argillites and quartzites of this
formation pass under the Spence's Bridge Vol-
canic group.

Between Spatsum and Toketic there are two
places to be seen from the railroad where the
Jura-Trias rocks rest unconformably upon the
Cache Creek formation. The largest outlier is
on the west side of the river and forms a high
hill separating the Thompson from Venables
valley. Venables creek flows through the south-
ern end of the exposure, and has exposed a very
fossiliferous section near 89-Mile Stable on the
Cariboo road.

The other outlier, which is in a badly
metamorphosed condition, outcrops high up on
the east side of the Thompson valley above
the great rock slide, at the base of which is
nestled an Indian village and church. The
Jura-Trias is here in contact with the grano-
dioritic batholith and basal Cache Creek rocks.

There are a series of strike ridges and ravines
paralleling the cliff face 1,500 feet (457-2 m.)
above the railroad. The Jura-Trias metamor-
phics dip flatly to the west while the underlying
Cache Creek rocks, where observable, dip
steeply to the east. The Jura-Trias rocks are
crevassed along joint planes nearly at right
angles to their bedding.

A couple of miles south of the Rock slide at
the mouth of Pukaist creek, the railroad cuts
transversely through Cache Creek marble, well
exposed across the river in the Canadian Nor-
thern Railway tunnels.
67-2 m. Toketic — Altitude 810 ft. (246-8 m.). At
108 • 1 km. Toketic a series of volcanic rocks commence
which have been correlated and mapped as the
Lower Volcanic group (Miocene?) by G. M.
Dawson, but regarding whose age there is

253

KUomefres much doubt. The writer regards them as Jura-
Cretaceous. These volcanic rocks, which con-
tinue as far as Thompson Siding, have, for con-
venience, been named the Spence's Bridge
group. They consist of a badly altered series,
chiefly of liparitic and andesitic lavas with
interbedded conglomerate, arkose and tuff, the
latter containing plant remains of Lower Creta-
aceous and Upper Jurassic age.

A light yellowish member of the Spence's
Bridge Volcanic group is prominently exposed
below the mouth of Twaal creek, on the west
side of the valley, where the river begins to
take a westward course. This is a peculiar
acidic lava, with spherulites averaging f inch
(i cm.) in diameter and having in places pro-
nounced flow structure. The acidic lavas are
intruded by basic dykes, possibly the feeders for
the younger Miocene basalts.

One mile above Spence's Bridge the broad
glaciated valley of the Nicola joins that of the
Thompson.

72 • 6 m. Spence's Bridge — Altitude 768 ft. (234 • o m.).
1 16 -8 km. Spence's Bridge, the junction point for the
Nicola Valley railroad, is picturesquely situated
in Thompson valley at the base of the precipit-
ous Arthur's Seat mountain.

Arthur's Seat, rising abruptly 5,500 feet
(1,676 m.) above sea level, is thought to have
been one of a series of volcanic vents which
were active along the east front of the
Coast range in Jura-Cretaceous time. At the
base of Arthur's Seat may be seen silt escarp-
ments, from which a large volume of alluvium
broke away on Aug. 13, 1905, damming the
Thompson river and causing the destruction of
an Indian village across the river. Five Indians
were buried alive in the slide, ten were killed
and thirteen hurt by the wave which swept
up the river.

79-1 m. Drynock — Altitude 752 ft. (229-2 m.). A
127-2 km. few miles below Spence's Bridge, the narrowing
valley swings southward and maintains a

254

Miles and southward course until it reaches Thompson

Kilometres. . ^

Siding.

The Spence's Bridge Volcanic group is capped
a few miles northeast of Drynock by typical
basalt of the Kamloops Volcanic group. About
ioo feet (30-5 m.) of tuff beds, resembling
the Tranquille beds, are present at the contact.

85-3 m. Thompson Siding — Altitude 670 ft. (204.2 m.).

137-2 km. At Thompson Siding, the Nicoamen river
tumbles over a waterfall to unite with the
Thompson which here bends sharply, taking
a west course until it reaches the Fraser river
at Lytton. The first discovery of gold in
British Columbia is said to have been made by
an Indian at the mouth of the Nicoamen in 1857.
As the train rounds some of the rocky bluffs on
the south side of the Thompson Canyon,
an occasional glimpse of the snowclad Stein
Peak and other Coast Range mountains may
be had. The scenery through this canyon
portion of the Thompson valley is rugged
and mountainous, with huge talus blocks
scattered along the channel of the river. There
is comparatively little Glacial silt in this portion
of the valley. The post-mature upland of the
summits grades gradually into the alpine topo-
graphy of the Coast range. As the train winds
through higher upland country, there is a
marked increase in the depth of the tributary
valleys beneath its surface.

Westward of Thompson, the railroad cuts
into highly pyritic quartz schists before entering
the eastern border of the Coast Range batholith.

89-7 m. Gladwin — Altitude 745 ft. (227-0 m.). A

144-3 km. contact zone between the Coast Range batho-
lith and Paleozoic schistose rocks, the whole
traversed by many Tertiary dykes and chono-
lithic intrusions, is exposed on the steep scarped
north wall of the canyon between Gladwin and
Lytton. A few miles further west, near the
mouth of Botanie creek, is an odd granitic
ridge named 'The Crag.' It is cut off sharply
to the west by a fault scarp which gives a very
irregular outline to the hill. The eastern side

256

Kiiomeu-^ ^as a relatively gentle slope, dotted with
evergreens.

A small detached area of Cretaceous shale,
sandstone and conglomerate, all much disturbed,
occurs near the mouth of Botanie creek about
two miles (3-2 km.) from Lytton.

From Lytton mountain, which rises about
6,000 feet (1,829 m.) southeasterly above the
town, may be seen on a clear day, the Cascade
mountains in Washington, and similar rugged
alpine summits supporting glaciers and neve
fields in the Coast range.

COAST RANGE (Lytton to Vancouver)

Charles Camsell.
INTRODUCTION.

From Lytton to Vancouver, a distance of 156 miles,
(251 km.), the route of the excursion follows the valley
of Fraser river. This stream, discovered and explored
by Simon Fraser in 1808, is the largest stream in British
Columbia whose basin lies entirely within the boundaries
of the province. It has a length of 790 miles (1,271 km.)
and drains an area of 91,700 square miles (237,686 sq. km.)
Rising on the western slope of the Rocky mountains in
latitude 530 N., it first flows northward in the great struc-
tural valley known as the Rocky Mountain trench until
it reaches latitude 540 15' where it bends with a wide
curve to the west and then to the south. From Fort
George its course is almost due south until it reaches
Hope, where, in turning westward, it breaks through
the mountains bordering the Pacific coast and within
100 miles (161 km.) empties into the Strait of Georgia.

In its course from Lytton to the sea the Fraser traverses
two strongly contrasted types of physiographic form, one
the rugged mountainous region of the Coast and Cascade
Mountain systems, and the other the comparatively level
region of the delta. The former of these two physiographic

257

units comprises a broad mountainous belt lying between
the Interior Plateau region and the coast, which has an
average width of about 100 miles (161 km.), and a length
in Canada of about 900 miles (1,448 km.) It is made
up largely of a composite mass of plutonic igneous rocks
called the Coast Range batholith, which has been thrust
through, and is flanked by, Paleozoic and Mesozoic sedi-
ments, blocks of which have been engulfed and are infolded
in it.

The delta portion is relatively small and in Canada
has an area of over 1,000 square miles (2,592 sq. km.)
though it also extends southward into the State of Wash-
ington. It is floored by Eocene deposits of estuarine
origin which are covered by more recent Glacial and post-
Glacial materials.

COLUMNAR SECTIONS.

(By N. L. Bowen).
Eastern part (Lytton to Hope).

Pleistocene and Recent — Till, stream gravels, etc.
Unconformable relation.

258

Lower Cretaceous
— Jackass Mt.
series.

Erosion surface.

Conglomerate, 2,000 ft. (609 m.).
Black shale, with marine shells, 500 ft.
(152 m.).

Green and grey arkoses, with plant
remains; 300 ft. (91 m.).

Base not exposed.

Unconformable relation.

Lower Mesozoic —

Boston Bar group — Thin-bedded grey argillites.
Palaeozoic —

Cache Creek group — Cherty argillites, limestone, quart-
zite, serpentine; thickness and order of succession
indeterminate.

Western part (Hope to Vancouver).

Quaternary — Till, stream gravels, etc.
Unconformable relation.

[Basaltic and andestic lavas.

Eocene ^Conglomerates, grits, shales with plant

[remains; 3,000 ft. (914 m.).
Unconformable relation.

Lower Cretaceous? — Quartz porphyry flows.
Unconformable relation.

[Limestone, 1,000 ft. (304 m.).
Palaeozoic — Black shale, 3,000 to 4,000 ft. (914 to

Agassiz series — j 1,219 m.).

I Conglomerate, 3,000 to 4,000 ft. (914 to
[1,219 m.).

The above sections do not include the granitic rocks,
which are apparently of two ages, Jurassic and post-
Lower Cretaceous. The older rocks are usually gneissic
and sometimes sheared, and include both granodiorites
and granites. The younger rocks are always fresher and
never gneissic, and usually more acid than the older type.
They are dominantly hornblende-rich, in contrast to the
older type in which the hornblende is subordinate to a
greenish biotite.

259

THE CANYON OF FRASER RIVER.

Physical Features.

Above Lytton the Fraser flows through the Interior
Plateau region, but from that point down to the head of
the delta below Hope it is closely hemmed in by the high
mountains of the Cascade lange on the one side and of
the Coast range on the other. These two mountain systems
overlap each other for about 100 miles (161 km.) and in

Entrance to Fraser canyon above Yale, with Lady Franklin Rock in the middle of

the stream.

the break between the over-lapping edges the river forces
a difficult passage until it eventually emerges from them
at the head of the delta, to pass around the southern end
of the Coast range. This part of Fraser valley is, properly
speaking, the canyon of the river though it has become
customary when speaking of " Fraser Canyon" to refer
to an inner gorge-like constriction 25 miles (40 km.) in
length extending from North Bend to Yale.

Throughout its length the main canyon is deep and
bordered by mountains which in places reach an altitude
of 7,000 feet (2,133 m0 above the sea. The sides of the
valley are generally rocky and steep, though the degree
of slope varies with the nature of the rocks in which it
is cut. For example, it is narrow and very steep-sided where

260

located in granitic rocks, and broader and more open
where the bed rock is the more easily eroded sedimentary-
rocks. In cross-section it is more or less U-shaped from the
effect of valley glaciation.

In the wider portions of the main canyon gravels have
accumulated to a considerable depth, but in the more
constricted parts deposits of this nature are rare and of
very limited extent. The gravels were deposited in the
closing stages of the Glacial period, but as a result of later
deepening of the stream bed a large part of them has been
removed and the remainder left as terraces, marking
successive stages in that deepening. As many as a dozen
terraces can be counted in the valley at Lytton. Uplift
since Glacial times has given the stream such renewed
power of erosion as to cause it to cut dcwn not only through
the sands and gravels, but even to deepen its bed into the
solid rock, leaving rock benches here and there on one side
or other of the valley bottom. Benches of this nature
are noticeable at Spuzzum and near Saddle Rock.

The grade of the stream varies from about 4 feet to the
mile (-76 m. per km.) in the portions above and belcw the
inner canyon to 8 feet to the mile (1-52 m. per km.) in
the inner canyon itself.

Virtually all the streams tributary to the Fraser river
along the main canyon, and particularly those of small
volume, enter through hanging valleys. The develop-
ment of the hanging valleys is in the main due to glaciation
though in one or two instances the hanging valley effect is
heightened by post-Glacial deepening of the main stream
itself.

GEOLOGY.

Stratified rocks of Carboniferous age (Cache Creek)
consisting of cherty quartzites, argillites, limestones,
serpentine and volcanic flows are the oldest rocks in the
main canyon. These rocks have been greatly disturbed
and now dip at high angles, striking diagonally across
the river. They have been in part intruded by granitic
rocks and in part covered by later stratified rocks so that
they now have a small areal extent.

Plutonic igneous rocks, mainly granodiorite, are exposed
throughout a great part of the main canyon, especially
in the gorge below North Bend. They belong to the great

26l

Coast Range batholith, and while the major portion of
them is of Jurassic age, some are believed from their
structure, to be post-Lower Cretaceous. These rocks,
especially the older ones, show shearing and faulting and
have two well developed lines of fracture, namely N. I5°W.
and N. 20° E., which to a considerable extent influence the
direction of the stream. From Yale to Hope they are
traversed by a wide shear zone striking north and south,
and along this the stream has directed its course.

Lower Cretaceous rocks occupy the valley of the river
below Lytton, and appear as erosion remnants near Hope;
they consist of conglomerate, slate and sandstone, which
contain a few marine fossils.

No deposits of Tertiary age occur in the main canyon,
though in the delta immediately below there is a great
thickness of Eocene beds, and in the region above the
canyon are Oligocene sediments, associated with volcanic
flows.

Glacial deposits of till, sand, and gravel fill the lower
parts of the valley wherever they have found space for
lodgment. They have been carved into terraces by the
stream, and more recent deposits of gravel have been
formed. These recent gravel deposits are the high-grade
gold-bearing placers which caused a great influx of placer
miners to the region in 1858 and the years following, and
from which many millions of dollars worth of gold have
since been won.

ORIGIN AND HISTORY OF FRASER CANYON.

The origin and history of Fraser canyon are by no means
clear. In attempting to work them out, one need not go
farther back in geologic time than the revolution following
the deposition of the Lower Cretaceous rocks. It is clear
from the geology of the region that during Lower Cretaceous
times no stream could have existed along the present
course of the river, for the region of the canyon was at that
time a geosynclinal basin occupied by an arm of the sea.
This region was however elevated into a land area in later
Cretaceous times. The development of drainage systems
must then have begun in this region, and among them
very probably that of the Fraser river, for reasons which
follow.

262

It is generally conceded by all who have worked in the
central part of British Columbia that the development of
the plateau features of the interior were initiated by long
continued erosion acting throughout Eocene times. The
enormous amount of material eroded during this period
must have been carried away by streams and deposited
elsewhere, and the only considerable development of Eocene
beds in that part of the continent is found in the delta
of the Fraser river and in the neighbouring parts of the State
of Washington. The structure of these beds indicates
clearly that they were laid down as delta deposits in an
estuary of the sea; while in shape they have here a deltoid
arrangement with the apex of the delta pointing up Fraser
valley towards the lower end of the canyon. The shape of
these Eocene deposits suggests that the stream, which
carried the material of which they are composed, had its
outlet at or near the lower end of the present canyon and
it is probable that the course of that stream was along the
present course of the river at least as far as the Interior
Plateau region. This evidence, however weak, is the first
that we have of any stream existing along the present
course of the Fraser river.

However, G. M. Dawson, who has studied the history
of Fraser river above the canyon, reached the conclusion
that the course of the river, as it exists to-day in the plateau
region, was only defined since the deposition of certain
flat-lying Miocene or Oligocene beds, through which the
river now cuts. Those beds however could have been
deposited in a lake or an expansion of the river where still-
water conditions prevailed along its course.

The selection of the course of the stream along its
present lines has been governed largely by the structure of
the rocks through which it flows. For example, for 8 miles
(i2-8 km.) below Lytton it flows in a band of Lower
Cretaceous rocks which have been down faulted against
the granite rocks and beyond this it follows closely the con-
tact of these Lower Cretaceous rocks with the underlying
Palaeozoic formation as far as North Bend. Also, in the
gorge below this, though the trend of the valley is in the
main due south, in detail the course of the stream has
two well defined directions which correspond to two lines
of weakness in the granite rocks in which it is cut. These
two lines of weakness strike N. 20° E. and N. 150 W. Below
the gorge also the valley is carved out along structural

263

lines in the bed-rock formation. The canyon of Fraser
river is therefore a subsequent valley and is developed as a
result of rock structure. The composition of the rocks,
however, has had a marked determining effect on the shape
of the valley, for it is wide in the soft sedimentary rocks
and sheared granitic rocks but is narrow in the massive
igneous rocks.

Fraser river, looking down from Yale; valley here widened out on greatly sheared
granite of the Coast Range batholith.

If the course of Fraser canyon was denned in Eocene
times it is very likely that it has followed the same channel
down to the present, for the Eocene beds of the delta show
that there was no great structural disturbance, even in
Miocene times, in that part of the valley, such as might
cause the stream to shift its course. The absence of
Miocene and Pliocene delta deposits does not necessarily
disprove the idea that the stream persisted along that
course throughout those periods, because deposits of those
ages were probably carried farther out to a point now
covered by the sea before they came to rest, or if deposited
sooner have since been eroded away. It is more than
likely, therefore, that, having defined its course in Eocene
times, the Fraser has persisted along that course down to
the present.

Long-continued erosion, acting throughout the early
and middle Tertiary, must have produced, by the beginning
35069— I IA

264

of the Pliocene period, a fairly mature valley with wide,
flaring sides, and a floor several hundred feet above the
present stream bed. A well defined topographic break on
the slope of spurs projecting into the valley 1 ,500 (457 m.) to
2,000 feet (784 m.) above the present stream bed may
mark the old valley slope. When the Pliocene uplift took
place, elevating the Cascade range and the adjacent
part of the Coast range, the stream was revived and the
deepening of the gorge was begun.

At the close of the Pliocene the canyon was problably
sharper than the present canyon with, however, the
same variations in character due to the relative resis-
tance of the rock formations Glaciation subsequently
widened the bottom of the valley to its present shape.

At the close of the Glacial period the land was depressed
below its present level and unconsolidated deposits of sand
and gravel were laid down in the bottom of the valley to a
depth of several hundred feet.

Elevation of the land in relation to the sea has since taken
place, and the erosive power of the stream has again been
revived. It has consequently cut down through the
Glacial deposits, leaving a series of terraces at different
levels to mark successive stages in the deepening of the
valley. In the gorge, deepening has progressed through
these Glacial deposits and into the solid rocks below to a
depth of about 100 feet (30-5 m), leaving remnants of the
old valley floor as rock benches on one side or the other of
the stream. The amount of uplift appears to have been
greater in the interior than on the coast.

REFERENCES.

Selwyn, A. R. C. — G. S.C., Rep. of Progress 1871-72,
Part II. Rep. of Progress 1877-78,
Part B.

Dawson, G. M. — G.S.C., Rep. on Kamloops Map Sheet,

Vol. VII , Part B. 1894.
Camsell, Charles — G.S.C., Summary Report, 191 1.
Bowen, N. L. — G.S.C., Summary Report, 1912.

Legend

1 T? 1 Tertiary

T4- Oligocenef?)

Upper vol can ic group
chiefly basalts

Tl Eocene(?)

Acidic lavas

Eocene

Sandstone , conglomerate
clay and lignite.

Cretaceous

Jurassic and Tertiary

Granitic rocks of the
Coast Range batholifh

Car 6 oniferous

Geological Survey, Canada.

Route map between Lytton and Agassi z

Kilometres
1 12

265

ANNOTATED GUIDE.
(Lytton to Agassiz).

Miles and

(FromVytton.) Lytton — Alt. 687 ft. (209. 3m.). The Thomp-
o m. son river empties into the Fraser at the town of
o km. Lytton, and from this point westward to the
Pacific coast the railway follows the course of
the Fraser river, which for about 80 miles
(129 km.) cuts a deep canyon-like valley
through the mountains bordering the coast,
and afterwards flows for 70 miles (112 km.)
through a delta of its own construction to the
sea. In the neighbourhood of Lytton a series
of well developed river terraces can be seen
in the lower part of the valley. These terraces
mark successive stages in the deepening of the
valley since the deposition of drift material in
the closing stages of the Glacial period.

For eight miles (12 -8 km.) below Lytton the
rocks in the immediate neighbourhood of the rail-
way are of Lower Cretaceous age striking
nearly parallel to the river and dipping at low
angles. To the west these rocks are in contact
with granitic rocks against which they are down
faulted. The attitude and structure of the
Cretaceous rocks is well shown at the bridge
near Cisco, where the railway crosses to the
west side of the river. There also a tunnel cuts
through the fossiliferous black shale of this
series.

8 m. Kanaka — Alt. 623 ft. (189.8 m.). At

12-8 km. Kanaka a belt of Palaeozoic rocks appears to the
west of the river and for a few miles southward
the river follows the line of contact between
these rocks and the Lower Cretaceous. About
three miles (3-2 km.) below Kanaka, Jackass
Mountain, which is made up of massive con-
glomerates overlying black shale, rises as a long
steep bluff from the water edge. In the course
of building a line along the face of the bluff
the Canadian Northern railway company has
been seriously handicapped by rock slides
35069— 11 Ja

266

Knomlu-es which have left great gashes in the side of the
mountain.

14 m. Reefers — Alt. 555 ft. (169m.). Near Keefers
22-5 km. and below it the Palaeozoic rocks occupy both
sides of the valley and continue to a point
three miles (4-8 km.) below North Bend.
27 m. North Bend — Alt. 487 ft. (148 m.). About

43-4 km. two miles (3-2 km.) above North Bend the
banded grey argillites of the Boston Bar series
appear. These rocks have yielded Dr. Bowen a
single, definitely Mesozoic fossil. Since they are
cut by the late Jurassic granites, they are either
Jurassic or Triassic in age. Much placer gold
mining was at one time carried on in this part
of Fraser valley, and the evidence of such
work is still to be seen in many places, particu-
larly at Boston Bar, a mile below North Bend.
Three miles (4-8 km.) below North Bend, the
Palaeozoic sedimentary rocks are intruded by
granitic rocks of the Coast Range batholith.
The contact however is not a clean-cut line of
separation between the two formations, but is
rather a wide zone marked on the side of the
intruded rocks by numerous apophyses of the
igneous rocks in the sedimentary, and on the
side of the batholith by inclusions of the Car-
boniferous rocks in the batholith. The zone of
apophyses is well shown in the railway cuts on
the west side of the river.
32 m. China Bar — Alt 466 ft. (142 m.). Turning

51-5 km. a sharp bend in the course of the valley four
miles (6 -4 km.) below North Bend, the railway
enters what is popularly known as "Fraser
Canyon," a narrow rock- walled gorge in the
main canyon, cut into the massive granitic
rocks of the Coast Range batholith, which here
form the axis of both the Coast and Cascade
Mountain systems. The gorge has a length
of 25 miles, (40-2 km) and though a serious
barrier both to water and land transportation,
it forms the only natural route of travel between
the coast and the interior of British Columbia.

Although referred to as a canyon for the
whole 25 miles (40-2 km.) of its length it is

268

Kilometres not uniformly canyon-like throughout, but
is rather a succession of narrow gate-like con-
strictions connecting somewhat broader expan-
sions of the river. Through these narrow
passages the water rushes with greatly increased
velocity and tremendous force, swirling and
eddying from wall to wall and forming such a
confusion of currents as to make the navigation
of these gaps exceedingly hazardous in low
water and absolutely impossible in a high
stage. Hell's Gate, Black Canyon, and Cha-
quama Canyon are among the most remarkable
of these constrictions, the first and last men-
tioned each having a width of about 200 feet
(61 m.).

For almost its entire length the gorge is cut
into granitic rocks of medium acid composition,
the predominating type of which is a gneissic
granodiorite. Though the larger proportion
of these rocks is of Jurassic age, some are con-
siderably younger and from their structure
and lack of metamorphism are probably
of early Tertiary age. These younger rocks
are easily identified even from a distance by
their well developed and regular places of
jointing; because of this characteristic they
have been used to a large extent by the rail-
way companies in the lining of tunnels and in
other types of masonry.

Skuzzy creek, a roaring torrent, plunges out
of a hanging valley into the Fraser river at
China Bar near the upper end of the gorge.
On the opposite side of the river in a steep
bluff can be seen a network of light-coloured
aplite dykes traversing the granodiorite. The
stream here runs in an almost direct line
southward, gradually becoming narrower until
two miles (3-2 km.) below, it rushes through
Hell's Gate between vertical walls of massive
jointed granodiorite.
43 m. Spuzzum — Alt. 395 ft. (118 -8 m.). Beyond

69*2 km Hell's Gate the railway enters a succession
of tunnels cut through projecting bluffs of rocks
in a moderately widi part of the valley, on

269

KUomeSL passing which the valley again narrows quickly
to the constriction called "Black Canyon".
Here, as elsewhere throughout the length of
the gorge the line of the Canadian Northern
railway can be seen under construction on the
opposite side of the river. A number of bridges
slung on wire cables and used by the builders
of that line span the river in several places.
The remains of the old Alexandra Bridge,
where the historic Cariboo road crossed the
river, can still be seen two miles (3-2 km.)
above Spuzzum. The Indian village of Spuz-
zum, a mile below the station of the same name,
is built on a delta fan of Spuzzum creek.

Saddle Rock — The valley widens again at
Saddle Rock where it passes over for at
short distance from the batholith into tilted
Carboniferous rocks. At Saddle Rock, and a
"Chaquama Canyon" 2 miles (3-2 km.) below,
where the stream is only 200 feet (60-9 m.) in
width for a distance of 1,000 feet (304-8 m.),
rock benches have been developed on the west
side of the valley as a result of post-Glacial
deepening. A number of shorter constrictions
follow in the next 4 miles (6-4 km.). One mile
and a half (2-4 km.) before reaching Yale the
valley seems closed altogether and no outlet
is visible. The stream, however, takes a sharp
bend to the west, and after flowing around
Lady Franklin Rock, it suddenly emerge into
a broader open valley and the gorge is left
behind.

54 m. Yale — Alt. 215 feet (65-5 m.). Yale is one of

86 • 9 km. the oldest places on the Fraser river, having
been established by the Hudson's Bay Company
as a trading post in 1856, and was a place of
considerable importance in the early days of
the gold excitement in Cariboo. From this
point down to Hope, the valley of the river lies
in a wide shear-zone in an acid granite, forming
a phase of the Coast Range batholith; in con-
sequence of this its width is greater than that
which obtains in the gorge. The white cliffs

270

Miles and seen [n west side of the valley near Emory

Kilometres. , „ «- i • i •

creek show the effect of this shearing.
Choate —

65 m. Hope — Alt. 209 feet (63 • 6 m.) . Looking direct-
ion 7 km. ly down the valley from Yale, a high mountain
fills the view and at the base of this is the town
of Hope, from which point the old Dewdney
pack-trail, once the main highway to the
interior of the Province, runs eastward over
the mountain ranges. The Paleozoic rocks
are again in evidence at Hope, and on them
rest patches of Cretaceous conglomerate,
remnants of a larger synclinal basin which
once stretched southward, across the Inter-
national Boundary line.

75 m. Ruby Greek — Alt. 96 feet (29-3 m.). Half

120-7 km. a mile beyond Hope, a younger massive
hornblende granite appears, and from here
down to Agassiz at the head of the delta of the
Fraser, this is the prevailing rock, though occa-
sionally as at Ruby creek one sees exposures
of the Carboniferous rocks.

"The relationship of the later hornblende
granites to these sediments is particularly well
shown. Where the unroofing of the granite is
rather far advanced, it appears as fairly regular
masses elongated in a northwesterly direction
and therefore cutting across the strike of the
sedimentary rocks. Beds are truncated sharply,
but appear again on their strike, across a
width of two or three miles of granite, quite as
if no interruption had taken place. Where un-
roofing is still imperfect, granite occupies the
lower slopes of the hills and is capped by the
bedded rocks. These receive numerous dykes
and sills from the granite beneath, but preserve
their strike and dip entirely intact. In short,
there is shown most convincing evidence of
replacement, rather than displacement, of the
sediments by the invading magma." (N. L.
Bo wen.)

Although the trend of the valley is now direct-
ly across the strike of the mountain axes, the

271

Kilometres width increases gradually, the mountains, par-
ticularly on the southeast side, retreating
farther and farther back. The grade of the river
also changes and is reduced from eight feet to
the mile (1-52 m. per km.), which it held in
the gorge, to about three feet to the mile (-57 m.
per km.). The vegetation, too, becomes typical
of the Pacific coast and shows the effect of a
moist, warm climate on a rich soil.
86m. Agassiz — Alt. 54 ft. (16-5 m.). Agassiz

138-4 km. is virtually at the head of the Fraser delta. Five
miles (8 km.) to the north, at the southern end
of Harrison lake, is the hot spring known as
St. Alice's well. The waters, which contain a
large percentage of sodium and some potassium
sulphate, rise with a temperature of 1500 F.
out of the crevices in Cretaceous rocks near
the contact of a later hornblende granite. The
springs probably represent the last traces of
volcanic forces which were once active in this
part of the Coast and Cascade mountains and
of which Mt. Baker, to the south, is such a
striking witness.

FRASER DELTA.
Topography.

The delta of the Fraser river is compound in structure
and was built up at different times, beginning with the
Eocene. Its construction was continued at the close of
the Glacial period and is being carried on at the present
time. The region embraced within this compound delta
extends from Agassiz westward to the Pacific coast and
runs southward across the International Boundary line.
To the east it abuts against the Cascade range, and its
northern boundary is the Coast range, while its southern
limit is in the State of Washington.

The topography of the delta is in the main low and fairly
level, with elevations ranging from sea level to about
400 feet (122 m.) above it. However, here and there in
the upper part an isolated hill stands above the general
level, reaching an altitude of about 1,000 feet (304-8 m.)
above the sea. Sumas and Chilliwack mountains are
typical examples of the higher eminences.

272

Geology.

The oldest exposed rocks are the granitic rocks of the
Coast Range batholith, which border and underlie the
delta on the north.

Remnants of once more extensive Lower Cretaceous
rocks form some of the hills in the upper part of the delta,
and around these the more recent deposits were laid down.

Virtually the whole of the delta, with the exception of
those parts covered by the Cretaceous remnants, is believed
to be floored by stratified rocks of Eocene age, which
are referred to in the literature as the Puget group.
They consist of little disturbed beds of conglomerate,
sandstone and shale which were laid down by the ancient
Fraser river in an estuary of the sea. They have a thick-
ness of about 3,000 feet in Canada, but are much thicker
in the State of Washington. They contain a variety of
plant remains and some small seams of lignite.

The Eocene beds suffered erosion throughout the re-
mainder of Tertiary times, but towards the close of the
Glacial period were overlaid throughout by sands, gravel
and till. These deposits now constitute broad, flat- topped
plateaus about 400 feet (122 m.) high, which were once
continuous as the late Glacial delta of the river. They
have, however, since been dissected by the present stream,
as a result of post-Glacial elevation. This process of
dissection is related to the strong terracing of the Glacial
deposits in the upper part of the Fraser river.

A modern delta is at present being formed by the river
and pushed seaward into the Gulf of Georgia.

REFERENCES.

Bowman, Amos G.S.C. Vol. Ill, p. 66 A.

Daly, R. A G.S.C. Vol. XIV., p. 42 A.

LeRoy, O. E G.S.C. Report of a portion of

the Coast of British Columbia and
adjacent islands, 1909.

273

ANNOTATED GUIDE.
(Agassiz to Vancouver).

Miles and
Kilometres.

95 m. Harrison Mills — Alt. 40 ft. (12-2 m.). From
152-8 km. Agassiz to the coast the railway runs through
the agricultural country of the delta, which is
everywhere covered with deep alluvium and, in
consequence, rock exposures are rare. The
whole delta is believed to be floored by deposits
of Eocene age, which are covered by Glacial
and post-Glacial deposits of the same character.
Knobs of granitic rocks and Lower Cretaceous
quartz porphyries project through the more
recent deposits.

Harrison river is crossed at Harrison Mills,
and beyond, the railway curves around and be-
hind an outlying knob of these granitic rocks.
Hatzic — Alt. 30 ft. (9- 14 m.). As far down
114 m. Mission — Alt. 21 ft. (6-4 m.). as the sea
183-4 km. Silverdale. coast the

railway skirts the southern base of the Coast
Range mountains, which are composed of the
granitic rocks of the Coast Range batholith.
Occasionally cuts are made into projecting
points, which show their character. At Silver-
dale a part of the old floor on which the
Eocene delta deposits were laid down is exposed.
This floor is presumably part of the Coast
Range batholith, and its deeply weathered
character indicates that it was long exposed to
the action of weathering before the deposition
of the Eocene deposits. The irregularity of
that old floor, and the attitude of the Eocene
deposits in relation to the adjacent mountains,
suggest also that during the deposition of those
deposits the neighbouring region of the Coast
range was then, as now, one of considerable
relief.

Ruskin —

130m. Haney— Alt. 19 ft. (5-8 m.).
209 • 2 km.

274

Miles and
Kilometres.

132 m. Hammond — Alt. 21 ft. (6-4 m.). At Ruskin

212 -4 km. the Fraser is joined by Stave river. Six miles
(9-6 km.) up the latter valley is a hydro-
electric plant, generating at present 26,000
horse-power. Exposures of post-Glacial stream
deposits are now frequently seen in the railway
cuts. These stand at a level of 40 feet (12-2 m.)
or more above the present level of the stream.

140 m. Westminster Junction — Alt. 28 ft. (8-5 m.).

225-3 km.

144 m. Port Moody — Alt. 13 ft. (3-9 m.). Crossing

231-7 km. Pitt river near Westminster Junction, the rail-
way leaves the Fraser river and passes over a
bw divide to the head of Burrard inlet, the
southern shore of which it then follows to
Vancouver.

147 m. Barnet — In the cliffs along the

236-5 km. shore of Burrard inlet

Hastings — good exposures of the

Eocene beds may be seen.
156 m. Vancouver — These deposits have been
251 km. proved by borings to rest directly on the rocks
of the Coast Range batholith, and to have a
thickness under the City of Vancouver of
several hundred feet. They consist of sand-
stone, conglomerate and clay. They have the
structure of delta deposits and were probably
deposited in the delta of the ancient Fraser
river. They are well exposed in the sea-cliffs
at Stanley Park, where also they are intruded
by dykes of porphyrite.

C/,2,3,4.

Steve, ston
Luk

ical

Survey , Canada.

Route map between rfgassiz. and Vancouver

Miles

. ... 9 .... 9 >£

>o s o Ki'ongtres ZQ

GUIDE BOOK No. 8

Transcontinental Excursion C

Toronto to Victoria and return via
Canadian Pacific and Canadian
Northern Railways

PART III

ISSUED BY THE GEOLOGICAL SURVEY

OTTAWA
Government Printing Bureau
1913

GEOLOGY U§gA8I

277

CONTENTS.

PAGE

Vancouver Island.

by Charles H. Clapp.

Introduction 280

General geology and physiography 280

Annotated guide, Vancouver to Victoria (Excur-
sions C 1 and C 2, section I) 286

Geology of the region around Victoria 292

Physiography 292

General geology 294

Particular descriptions 311

Excursion Ci 311

Excursion C 2, section 1 314

Excursion C 2, sections I and II 316

Annotated guide, Vancouver to Nanaimo (Excur-
sion C 2, section II) 317

Geology of the region around Nanaimo 319

Physiography 319

General geology 320

Geology of the coal deposits 326

Particular description 331

Annotated guide, Nanaimo to Victoria (Excur-
sion C 2, section II) 334

References 341

Fire Clay Deposits at Clayburn, British
Columbia.

by Charles Camsell.

Introduction 343

Summary of geological history of Fraser delta. . . . 344

Annotated guide 345

Geology of the region about Clayburn 347

General description 347

Particular description 348

Industrial notes 348

Bibliography 349

Victoria, British Columbia, to Calgary, Alberta. 349
35069— 1 |b

278

PAGE

Calgary to Winnipeg \ia Canadian Northern
Railway.

by A. Maclean.

Introduction 349

Annotated guide, Calgary to Munson 350

The Edmonton formation on Red Deer river

near Munson, Alberta 350

Annotated guide, Munson to Dauphin via Saska-
toon . 355

Annotated guide. Dauphin to Ethelbert and Pine

River . 357

Annotated guide, Dauphin to Winnipegosis 362

Devonian of Snake island, and south shore of Lake

Winnipegosis 363

Devonian of Dawson bay, Lake Winnipegosis. . . . 366

Annotated guide, Dauphin to Winnipeg 369

Bibliography 370

Winnipeg to Port Arthur.

by A. L. Parsons.

Annotated guide, Winnipeg to Kenora 370

Pre-Cambrian geology in the northern part of

Lake of the Woods 371

General geology of the region 371

Keewatin 372

Laurentian 377

Later granite 378

Keweenawan 378

Gold mines of the district 379

Itinerary 379

Bibliography 384

Annotated guide, Kenora to Port Arthur 385

Port Arthur to Toronto 386

279

ILLUSTRATIONS TO PART III.

Maps.

page.

Victoria and vicinity (in pocket)

Route map between Victoria and Nanaimo (in pocket)

Red Deer valley in the vicinity of Drumheller 354

Old beaches, Ethelbert to Pine River 359

Snake island and south shore of Lake Winnipegosis 365

Dawson bay 368

Route map, Lake of the Woods (in pocket)

Drawings and Sections.

Block diagram, illustrating topography of southern Vancouver

island 285

Section exposed along the south shore of James island, illustrating

relations of superficial deposits 291

Sections of Wellington seam, showing rolls and overlaps. Where

represented as broken, seam inferred 329

Photographs.

Southern part of Vancouver range, showing uplifted and dissected
Tertiary peneplain with few and relatively low monadnocks.

Southern part of Malahat district, looking northwest from

Mt. Shepherd 283

South shore of Victoria, looking east to Finlayson point, showing
development of contraposed shore line. Hard rocks over-
lain by retrograded Vashon drift and May wood clays 295

Contact shatter-breccia at contact of Wark gabbro-diorite gneiss
and Saanich granodiorite, showing both angular and rounded

xenoliths; ledge south of Outer wharf, Victoria 304

Pillow structure in Metchosin basalts. Islets off south shore of

Albert Head, Vancouver island 306

Basal unconformity, shore west of Neck point, Wellington
district, showing the irregularities of the surface on which

the Nanaimo series was deposited 319

Galiano (Malaspina) gallery 332

Agglomerate; Kenora, Ont 374

Contact breccia, Keewatin and Laurentian. Barry lake 375

Brecciated contact, Keewatin and granite. Sultana mine 376

The Devil's Gap 380

Ellipsoidal trap. Shoal lake 382

Metamorphosed sericite schist; Slate island, Lake of the Woods 383

2 SO

VANCOUVER ISLAND.

Charles H. Clapp.

INTRODUCTION.

The Vancouver Island excursions afford an opportunity
to study the geology of a readily accessible area which is
fairly representative of the whole Pacific Coast region of
North America, and to examine the most important coal
field of that region. Features of wide geological interest
to be seen, are: — (i) Ancient volcanism, including flows
and fragmental rocks, denuded volcanoes, fossiliferous
tuffs, columnar jointing, and pillow structure. (2) Dyna-
mic and contact metamorphism of basic volcanics and
associated limestones producing marbles, amphibolites,
and garnet-diopside-epidote rocks. (3) Batholithic and
dyke intrusives, illustrating contact shatter-breccias,
differentiation, sequence of the different phases of igneous
activity, and origin of primary gneisses. (4) Sedimenta-
tion, illustrating unconformity, rapid lateral and vertical
gradation, calcarenites, sandstone dykes, and coal. (5)
Glaciation, grooves, striations, roches moutonnees, glacial
and interglacial deposits, such as deltas with terraces
and kettles. (6) Physiographic features, peneplain and
monadnocks, glacial lakes and fiords, and various types
of shore-lines. (7) Economic geology, contact deposits,
coal and other non-metallic materials.

GENERAL GEOLOGY AND PHYSIOGRAPHY.

Vancouver island (4) is one of the border ranges of
North America and is separated from the mainland by the
submerged northern portion of the great marginal de-
pression of North America, known as the Pacific Coast
downfold (17). This depression is flanked on either side
by great mountain ranges; in British Columbia by the
Coast range to the east and the ranges of Vancouver
island and Queen Charlotte islands to the west. The
Vancouver range, which virtually constitutes Vancouver

28l

island, trends N. 550 W. The entire island is 290 miles
(470 km.) long and 50 to 80 miles (80 to 130 km.) wide, the
total area being about 14,000 square miles (36,000 sq. km.).
It is, as stated, separated from the Coast range of the
mainland by the submerged northern end of the Pacific
Coast downfold, which is occupied from south to north
by Haro, Georgia, Johnstone, and Broughton straits
and Queen Charlotte sound. It is separated from the
mainland to the south, that is from the Olympic mountains
of Washington, by a smaller transverse downfold, striking
about N. 700 W., now occupied by the Strait of Juan de
Fuca.

Vancouver island is composed of deformed metamorphic,
volcanic and sedimentary rocks, intruded and replaced
by numerous irregular bodies of granitic rocks, and fringed
along both coasts with fragmental sediments, which rest
unconformably upon the metamorphic and granitic rocks.
The metamorphic rocks are largely of lower Mesozoic
age, presumably upper Triassic and lower Jurassic, but
they may include some Palaeozoic members. Apparently
the oldest rocks, considered provisionally as of late Palaeozoic
(Cariboniferous) age, are a series of slates and quartzose
schists, with some fragmental volcanic members. This
series extends across the southern end of the island and
is called the Leech river formation.

The lower Mesozoic rocks comprise the larger part of
Vancouver island, and constitute the Vancouver group.
They consist chiefly of metamorphosed basic volcanics,
principally meta-andesites, the Vancouver volcanics.
Certain schistose and more salic volcanic rocks are ap-
parently interbedded with the Leech river formation,
but the typical meta-andesites, although separated from
the Leech river formation largely by faults, are apparently
younger and unconformable. Associated with the Van-
couver meta-andesites and occurring chiefly in small
intercalated lentils, is a formation of limestones called
the Sutton formation. Besides the limestones, there
is associated with the meta-volcanics a series, of stratified
slaty and cherty rocks, the Sicker series, composed partly
of volcanic material. These rocks and their associated
volcanics have been greatly metamorphosed and converted
into schists.

All of the above mentioned rocks are intruded and partly
replaced by batholithic and dyke (minor intrusive) rocks.

282

The batholithic rocks are chiefly granodiorite with marginal
facies of diorite, but in the southeastern part of the island
there is a large batholith of gabbro-diorite and quartz-
diorite gneisses. All of the batholithic rocks are closely
related and appear to have been irrupted during the same
general period of intrusion. Nevertheless they may be
subdivided into four types that were irrupted in a definite
sequence, apparently as follows: — Wark gabbro-diorite
gneiss, Colquitz quartz-diorite gneiss, Beale diorite, and
Saanich granodiorite. It is probable that all the 'minor
intrusives' also, salic and femic porphyrites, were irrupted
during the same general period.

Unconformable upon an erosion surface of the metamor-
phic and granitic rocks, and confined for the greater part
to the east coast of the island, is a thick conformable
series of fragmental sediments, the Nanaimo series, largely
of upper Cretaceous age. It consists of conglomerates,
sandstones, and shales, with some coal. In general, it
has been deformed, into broad open folds with a northwest-
southeast strike, and a general northeast dip, but in places
it has been closely folded, overturned to the southwest
and broken by reversed and overthrust faults.

The deformation of the Nanaimo series probably occurred
in post-Eocene times. Previous to it, during upper-Eocene
times, a thick formation of volcanic rocks, the Metchosin
volcanics which are chiefly basalts, was accumulated in
the southern part of the island. These volcanics were
involved in the post-Eocene deformation, and at the same
time were intruded by stocks of gabbro, the Sooke
gabbro, which ranges from a femic to a salic gabbro and
even to true anorthosite.

In later Tertiary time during the erosion cycle initiated
by the post-Eocene deformation, the Vancouver range was
reduced to a subdued surface, which in its southern part
was a peneplain with a few monadnocks remaining a few
hundred feet above the general level. In its central part,
however, the surface was one of considerable relief, with
larger and higher monadnocks and small ranges of mountains.
During this cycle a large part of the detritus was deposited
off the southern and western coasts of the island against a
submerged mountainous slope, and formed a coastal plain,
composed largely of coarse conglomerates and sandstones,
the Sooke and Carmanah formations. The subdued and
peneplained Tertiary erosion surface and the coastal plain

284

deposits were subsequently uplifted, presumably during
Pliocene times, and were then dissected during a pre-
Glacial cycle, initiated by the uplift. Over the larger part
of the island, the dissection, which was presumably accom-
plished by revived, large, transverse streams with sub-
sequent tributaries, reached a stage of maturity, and the
Tertiary peneplain and subdued surface is still preserved
in the wide, relatively smooth interstream areas. The
present elevation of the uplifted Tertiary peneplain is
less than 1 ,500 feet (450. m.) near the southern coast, but
increases rapidly to the northwest, so that in the central
part of the island, the elevation of the uplifted subdued
surface is about 4,000 feet (1200 m.), while the old residuals
are now since uplift, 5000 to 7,000 feet (1,500 to 2,100 m.)
above sea level, a few peaks being even higher.

In the southeastern portion of the island, although the
region is largely underlain by crystalline rocks of the same
character as the rest of the island, the dissection was carried
to a further stage, that of late maturity to old age, so that
the Tertiary peneplain was entirely destroyed and another
subdued surface was developed several hundred feet lower,
now averaging about 100 feet (30 m.) above sea level,
but surmounted by numerous relatively small monadnocks.
The sedimentary rocks along the coasts, the Nanaimo series
along the east coast and the Sooke and Carmanah forma-
tions along the west coast, being less resistant than the
crystalline rocks which form the larger part of the island,
were also, reduced during the pre-Glacial cycle to a low-
land, exposing the mountainous slope against which the
Sooke and Carmanah formations were deposited. These
latter formations were, after further uplift, also retro-
graded so that now mere remnants of the former Tertiary
coastal plain exist, fringing the southern and western coast
of the island. It seems as if at some time following the
mature dissection of the uplifted Tertiary peneplain and
the development of the lowlands, the southeastern por-
tion of the island was depressed in part below sea-level,
drowning the valleys, but leaving the higher elevations
as islands and promontories, and thus forming the irregular
drowned coast characteristic of that part of the island.

In Pleistocene times, Vancouver island was apparently
smothered by a thick ice-cap, which smoothed and rounded
all the mountains under 4,000 or 5,000 feet (1,200 to 1,500
m.) high, while the pre-Glacial valley heads in the higher

285

mountains were excavated by local glaciers, so that these
high mountains now have characteristic serrated summits.
Valley glaciers occupied and scoured out the larger valleys,
converting some of them, chiefly the transverse valleys
flowing southwestward from the main range to the Pacific,
into fiords, and deepening some of the interior valleys
into large lake basins. The valley glaciers flowing east-
ward from the east slope of the Vancouver range joined with

Block diagram, illustrating topography of southern Vancouver island.

the larger and more numerous glaciers flowing west-
ward from the range of the mainland, and formed an exten-
sive piedmont glacier which occupied the downfold be-
tween the Vancouver range and the ranges of the mainland.
The southward flowing portion of this piedmont glacier,
[8] called the Strait of Georgia glacier, overrode the
lowland developed by the pre-Glacial cycle in southeastern
Vancouver island and sub-maturely glaciated it. On the
retreat of the earlier and larger glaciers of the Admiralty
epoch, the land stood at least 200 feet (60 m.) lower than
at present, and during an inter-glacial epoch, the Puyallup,
the lowlands developed by the pre-Glacial cycle were
covered by marine and delta deposits composed largely of
glacial detritus, the Maywood clays and Cordova sands
and gravels. During a later and less intense epoch of
glacial advance, the Vashon, the inter-glacial deposits were

286

partially eroded by the smaller glaciers. The apparently
rapid retreat of the Vashon glaciers left the inter-glacial
deposits partly covered by a younger drift and by large delta
deposits, the Colwood sands and gravels, built at the front of
the larger retreating valley glaciers.

A recent uplift of some 250 feet (75 m.) has caused a
partial recovery from the former depression, which, as
mentioned above, resulted in the drowned coast of south-
eastern Vancouver island, and has initiated the present
marine cycle. During this cycle the uplifted Pleisto-
cene deposits have been retrograded to form steep cliffs
some 250 feet (75 m.) high, while the coast, where composed
of the crystalline rocks, presents the initial irregularities
of the drowned glaciated surface. Inland the uplifted
Pleistocene deposits have been terraced by the streams
revived by the uplift, and the larger of the revived streams
have cut narrow canyons, from 100 to 300 feet (30 to 90 m.)
deep, in the hard rock.

ANNOTATED GUIDE.

VANCOUVER TO VICTORIA.

(Excursion C 1, and C 2, Section 1.)

Miles and
Kilometres.

o m. Vancouver — Leaving Vancouver the steamer

o km. sails westward through the narrow pass, called
the First Narrows, at the entrance of Vancouver
harbour, into the Strait of Georgia. To the
north are the lower mountains of the Coast
range, composed largely of granitic rocks, and
to the south is the low area underlain by the
relatively unresistent Eocene sediments, con-
sisting largely of sandstones and conglomerates,
only moderately disturbed, and well exposed
in the shore cliffs [9]. The Eocene sediments
are almost entirely covered with the thick
deposit of clay, sand, and gravel comprising the
Fraser River delta, built largely in post-Glacial
times and recently uplifted some 400 feet
(120 m.) and cliffed during the present marine
cycle so that the old delta appears conspicuously

287

Knome?res to tne east as tne steamer sa^s south in the
Strait of Georgia. The present delta of the
Fraser forms an extensive lowland, only a few
feet above sea level, that extends southwest
from the older, uplifted delta.

To the west is Vancouver island, a good
general view of which may be had in clear
weather. The dark mass of the Vancouver
range, composed largely of metamorphic and
crystalline rocks, steeply surmounts the coast
lowland, underlain by the less resistant sedi-
ments of the Nanaimo series. Most of the
summits of the Vancouver range are rounded
or ridge-like, but a few snow capped and
serrated peaks are seen crowning the whole.
44 m. Active Pass — Leaving the open Strait of

71 km. Georgia the steamer enters Active Pass and
for the next 25 miles (40 km.) sails through the
relatively narrow, but deep, channels between
the small islands off the southeast coast of
Vancouver island. Active pass affords a sec-
tion across the northeastward dipping upper
members of the Nanaimo series, and is doubtless
the result of the mature glaciation of a trans-
verse pre -Glacial valley by one of the rapidly
moving tongues of ice forced southward across
the valley by the large southward-flowing Strait
of Georgia glacier (8). An example of the rapid
lateral gradation of the Nanaimo sediments,
Northumberland formation [5], is here seen.
To the northwest of the central part of the pass,
on Galiano island, the sediments are chiefly
conglomerates with some sandstones, while to
the southeast along the line of strike on the
shores of Mayne island in Miners bay, the
same horizon consists chiefly of sandy shales,
although there is no offset in the Pass. Since the
dip of the sediments is about 20 degrees to the
northeast, the northeast or back slopes of the
islands have a cuesta form and are com-
paratively gentle, wThile the southwest or front
slopes are steep

Crossing Trincomali channel, which is a
drowned longitudinal anticlinal valley, the

288

steamer enters Swanson channel between Pre-
vost island on the northwest and Pender island
on the southeast On these islands, the Nanaimo
sediments, which are stratigraphically of a
lower horizon than on Galiano and Mayne
islands, are rather closely folded so that the dips
are variable and fairly high. Seen in the back-
ground to the south and west of Prevost island
is Saltspring island, the largest of the many
islands off the east coast of Vancouver island.
Its southern and central part is composed
largely of the metamorphic rocks of the Van-
couver group with intrusive bodies of grano-
diorite. Upon these the Nanaimo series lie
unconformably, the basal members being strati-
graphically considerably above the base of the
series in other localities. The metamorphic
and granitic rocks are seen surmounting the
Nanaimo sediments, attaining an elevation of
about 2,300 feet (700 m.), although the average
elevation of the comparatively smooth top,
which is a part of the uplifted Tertiary pene-
plain, is about 1 ,500 to 1 ,800 feet (450 to 540 m.).
A low valley underlain by Nanaimo shales
crosses the upland, and is bounded on the north
by a steep slope. This slope, which is underlain
by the metamorphic rocks with a cap of basal
conglomerates, has been developed along an
old fault, which separates the Nanaimo shales
from the upthrown metamorphics. The original
fault scarp was destroyed during the Tertiary
erosion cycle, but after the uplift of the
Tertiary peneplain, the less resistant Nanaimo
sediments were more rapidly eroded leaving
the metamorphics again in relief and pro-
ducing a new scarp, a fault line scarp along the
old fault.

Leaving Swanson channel, the steamer enters
Moresby passage between Portland island to
the west and Moresby island to the east.
Both islands consist largely of the older
metamorphics (Sicker series) and intrusive
granodiorites, although small areas of Nanaimo
sediments rest unconformably upon these older

289

rocks. Farther to the northwest the same
rocks form the southern part of Saltpsring
island, whose southern slope is another fault
line scarp, developed along a reversed strike
fault parallel to that described above, and which
has thrust the metamorphics against the
Nanaimo sediments to the south. These sedi-
ments, which are folded into a closed syncline,
overturned to the southwest, are exposed on the
small islands to the south of Moresby passage,
among which the steamer sails.

Leaving these islands the steamer enters the
more open waters of Bayan bay. To the west
is the town of Sidney, on the southeastern
lowland of Vancouver island. This lowland,
called here the Saanich peninsula, since it is
separated by Saanich inlet from the upland
of Vancouver island is underlain by the Saanich
granodiorite, most o which is greatly fractured
and altered. A less fractured portion of the
granodiorite forms Mt. Newton, altitude 1,000
feet (305 m.\ the largest monadnock of the vici-
nity, seen conspicuously to the southwest of
Sidney. The sky-line of the upland which is
the result of the mature-dissection of the
uplifted Tertiary peneplain, is fairly even, the
only pronounced irregularities being the large
steep-sided valleys and occasional small monad-
nocks.

From Sidney channel between James inland
on the west and Sidney island on the east, the
glacial deposits which mantle much of the
southeastern lowland of Vancouver island are
seen. Indurated rocks are not exposed on
James island, and on Sidney island are exposed
only in the southern part. The deposits,
consisting of Maywood clays covered by Cordova
sands and gravels, are chiefly inter-glacial and
largely of marine origin. At the northern
end of Sidney island is a brick plant which uses
the Maywood clays. The inter-glacial deposits
are strewn with large glacial boulders and are
partly covered by the younger Vashon drift
They were in part eroded during the Vashon

290

laiomSra glacial epoch, and upon the retreat of the Vashon
glaciers the uneroded portions of the inter-glacial
deposits were left as long, nearly straight,
esker-like ridges, their axes having a general
strike of S. 250 E. Since the retreat of the
Vashon glaciers and the comparatively recent
uplift these deposits have been rapidly retro-
graded into the steep cliffs about 100 feet
(30 m.) high, which are seen on both James
and Sidney islands. The retrograded material
has been carried northward by the prevailing
shore currents, building the long spits and
beaches that are seen extending north from
Sidney island. As the steamer leaves Sidney
channel, the mature southern shore of James
island is seen. Here the inter-glacial deposits
have been retrograded, presumably for over
a mile, resulting in a straight shore line with
nearly vertical cliffs, which in the central
portion is over 200 feet (60 m.) high. An
idea of the rapidity of the retrogression of this
shore is shown by a wire fence, which in 1907
was built to the edge of the cliff and which
in 1910 had been undermined for 24 feet (7 • 3 m.)
apparently not all at once but gradually, as
that part of the cliff was retrograded uniformly
with the rest. It is improbable however,
that the entire shore-line is being retrograded
at the rate of 6 feet (i-8 m.) a year, but the
rate is doubtless more than one foot (0-3 m.).
As a result of this retrogression a good section
of the till-covered deposits is obtained, affording
a proof of their inter-glacial origin, and of the
fact that the inter-glacial drift ridges are erosion
remnants of once more extensive deposits and
are not constructional forms, since the outline
of the present surface of the ridge cuts sharply
across the bedding of the deposits. The
southern shore of Sidney island is in marked
contrast to that of James island, for on
Sidney island the drift which doubtless originally
covered the hard rocks, has been largely removed
and a very irregular shore-line, still in an early
stage, is the result. This has been called,

291

in order to show its analogy to a superposed
valley, a contraposed shore-line.

Leaving Sidney channel, the steamer enters
Haro strait between Vancouver island and
San Juan island. To the east, the small
D'Arcy islands, composed of the Vancouver
volcanics, are seen, and to the west the retro-
graded inter-glacial deposits covering the south-
eastern part of the Saanich peninsula. To the

Horizontal scale ■ ■ . f 52* !°P° feet

Vertical scale exaggerated 2. times

\ °°- °] tins t ratified Vashon drift

Stratified Cordova sands and gravels
Strati fied May wood clays

Section exposed along the south shore of James island, illustrating relation of superficial deposits.

southwest is a conspicuous monadnock, Mt.
Douglas, altitude 725 feet (220 m.), which
surmounts the lowland developed in the vicinity
of Victoria.

Leaving Haro strait, the steamer passes
between Vancouver island and several small
islands, Discovery, Chatham, and Chain islands,
which are composed largely of the Wark gabbro-
diorite gneiss. Turning westward from these
islands towards Victoria harbour the route
follows for a short distance the great
transverse downfold occupied by Juan de
Fuca strait which lies between Vancouver
island and the Olympic mountains to the south.
The Olympic mountains, which are composed
largely of pre-Tertiary metamorphics similar
to the metamorphic rocks of Vancouver island
fringed by upper Eocene basalts and Miocene
sediments [2 and 14], seem to rise abruptly
from sea-level to elevations of 6,000 to 8,000
feet (2,000 to 2,500 m.), their serrated peaks

35069— 2B

292

Miles and covered with large glaciers and snow fields.

Kilometres. _ , 11 1 ,

To the east on clear days may be seen the
Cascade range of Washington with the denuded
snow-and glacier-capped volcano, Mt. Baker,
towering above the highest peaks for 4,000 feet
(1,200 m.) and attaining an elevation of 10,694
feet (3,260 m.) To the northwest, the com-
paratively low, flat- topped, heavily wooded
range of Vancouver island, attaining elevations
from 1,500 feet (450 m.) to 3,000 feet (900m.),
forms the background, while in the foreground
is the pre-glacial lowland of the vicinity of
Victoria, surmounted by many small monad-
nocks.

Rounding Trial islands which ar composed
of the Vancouver meta-andesites, the steamer
gradually turns northward and finally enters
Victoria harbour, a comparatively narrow and
small inlet, formed by the depression below
sea-level of one of the submaturely glaciated
valleys of the southeastern lowland. To the
east is the city of Victoria, and to the west is
the Esquimalt peninsula.

84 m. Victoria —

135 km.

GEOLOGY OF THE REGION AROUND VICTORIA.

Physiography.

The region around Victoria [4] consists almost entirely
of the lowland developed in the southeastern part of
Vancouver island during the pre-Glacial cycle. The
lowland is not smooth, but, except where covered by drift
deposits, is characterized by small irregular valleys and
by a great number of rock ledges. The valleys are well
adjusted to the weaker parts of the rocks, shear zones
and joint planes, and frequently follow contacts, even
where the contacts are irregular. The lowland is drained
chiefly by numerous wet-weather streams with an inter-
mittent flow, there being no larger rivers. Surmounting
the lowland from 100 to 600 feet (30 to 180 m.) are numerous
but relatively small monadnocks, and in ths western part

293

of the region is an upland transitional in character between
the lowland and the upland of the Vancouver range, formed,
as described, only by the mature dissection of the previously
uplifted Tertiary peneplain. In the upland portion of the
region around Victoria, the dissection of the Tertiary
peneplain reached a further stage, one of late maturity,
in which virtually, all of the uplifted peneplain was
destroyed, although the region retains considerable relief.
The monadnocks do not correspond with the outlines of the
various rock formations, but have survived where the rocks
were less fractured and sheared or less altered. Most
of the monadnocks are roughly conical, but some are
elongate, corresponding with the trend of their component
rocks.

It was upon the lowland that the stratified drift was
deposited during the inter-glacial period, the lowland having
been previously scoured off by the southward flowing, pied-
mont, Strait of Georgia glacier, so that the elevations
are now knob-like, with relatively smooth, rounded
outlines. During the second period of glaciation, the
stratified drift was partially eroded. This left long,
esker-like ridges in the lea of some of the monadnocks,
and in some of the eroded hollows in the drift mantle
small lakes such as Swan and Lost lakes. In the upland
portion the scouring action of the glaciers is more evident,
especially of those valley glaciers that were confined between
the sides of deep valleys, and here there are small lakes in
deepened rock basins. Since the recent uplift the drift
deposits have suffered little erosion, although in the
western part of the region they have been terraced. In
this locality the drift forms a wide, flat plain, from 200
to 250 feet (60 to 75 m.) above sea-level, known as
Colwood plain.

It was apparently the depression of the glaciated and
drift-covered lowland with numerous monadnocks, fol-
lowed by a partial recovery, that formed the present
irregular shore line and the numerous islands of the region.
The initial shore line must have been rather simple, with
smooth flowing outlines where the crystalline rocks were
drift covered, but with many small, rounded and smoothed
irregularities where the glaciated rock surfaces were not
drift covered. During the present marine cycle, the shore
has been subjected to moderately strong erosion, and the
uplifted drift deposits have been rapidly retrograded to

35069— 2jB

294

form sea-cliffs 200 to 250 feet (60 to 75 m.) high with sand
spits and bars, and in some places, as on the shore of
Royal Roads, a nearly straight shore line. In many in-
stances, as along the shore south of Victoria, the drift
has been retrograded in places beyond the underlying
rocks. The hard rocks form small, sub-sharp to
rounded points, which project beyond the even, cliffed
shore line. In other instances, as on the shore of Esquimalt
peninsula, the drift has been largely removed, or else was
never deposited and a very irregular shore line is the result.
This irregular shore line, developed by retrogression of
the drift cover, is in marked contrast to the simple retro-
graded type, and as already mentioned, in order to emphasize
its analogy to the valley of a superposed river, has been
called a contraposed shore line. The larger part of the
coast is composed of resistant rocks, and virtually none of
the initial irregularities of the depressed glaciated rock
surface have been destroyed. On the contrary minor
irregularities, such as small coves and wave chasms have
been developed by wave action on the shear zones, joints,
dykes, and interbedded softer rocks. The hard rocks
themselves have not been beached, but since the retro-
graded drift deposits frequently occur between head lands
of hard rock, narrow beaches composed of their material
occur in the protected places of the headlands.

General Geology.

TABLE OF FORMATIONS.

Quaternary.

Superficial deposits.

Vashon Glacial deposits.
Colwood sands and gravels
Vashon drift.

Post-Glacial deposits
Beach alluvium
Valley and Swamp alluvium.

Recent.

Puyallup inter-Glacial deposits,
Cordova sands and gravels
Maywood clays.

Pleistocene, later Glacial epoch.

Stage of glacial retreat.

Stage of glacial occupation.
Pleistocene.

Admiralty Glacial deposits.
Admiralty till.

Pleistocene.

Earlier Glacial epoch.

296

Tertiary.

Metchosin volcanics,

Upper Eocene. Ophitic basalt flows tuffs
and agglomerates, with
intrusive diabase dykes.

Mesozoic.

Batholithic and minor in-
trusives

Diorite porphyrite
Saanich granodiorite
Colquitz quartz-diorite gneiss

Wark gabbro-diorite gneiss.

Upper Jurassic and possibly
Lower Cretaceous, correlated
with Coast Range batholith.

Dykes.

Vancouver group.
Sutton formation.

Vancouver volcanics.

Stocks.
Batholith of quartz-di-
orite gneiss, and quartz-
feldspar (salic) and horn-
blendite (femic) facies,
usually interbanded.
Batholith of gabbro-di-
orite gneiss, with un-
foliated gabbro and salic
gabbro facies.

Jurassic and Triassic.

Lower Jurassic
possibly includ-
ing Triassic. Lentils of crystalline lime-
stone in Vancouver vol-
canics.

Lower Jurassic
possibly includ-
ing Triassic. Metamorphic andesites,
basalts, and olivine bas-
alts, porphyries, amygda-
loids, tuffs, and agglom-
erates and intrusivedykes
and sills of basalt and
andesite porphyrites.

Vancouver group — The metamorphic rocks of the
region around Victoria are the Vancouver volcanics and
the Sutton limestones, both of the Vancouver group and
presumably of lower Mesozoic age. The Vancouver
volcanics, the more important formation, consist largely
of metamorphic flow rocks of medium basicity, meta-
andesites, and some meta-basalts. Interbedded with the
flow rocks are amygdaloids, and fragmental volcanics,
tuffs and agglomerates, and cutting them all are dykes
and sills of basalt porphyrite. All of the volcanics have
been metamorphosed and greatly altered, the secondary

297

minerals being chiefly uralite, chlorite, epidote, calcite,
and sericite. Such alteration is similar to that which
takes place under conditions of moderate to shallow depths
and moderate temperatures, and probably took place
during the folding and shearing that the volcanics suffered
in orogenic periods. However, near the contacts with
the intrusive granitic rocks the volcanics have been
greatly contact metamorphosed and some of them have
even been recrystallized or replaced, forming various
metamorphic types such as silicified and feldspathized
varieties, amphibolites, and even garnet-diopside-epidote
rocks. Analyses of the two last types are given below.
The volcanics are also seamed with veins of quartz and of
quartz and epidote, and in places are impregnated with
metallic sulphides, chiefly pyrite.

Si02

51-60

42-86

A1203

15-00

7-19

Fe203

1-85

14-24

Fe'O

8-48

4-28

MgO

7-15

2-96

CaO

7-63

26-30

Na20

3-09

0-27

K20

H20 +

0-70

o-33

i-95

I -00

Ti02

2-00

0-30

P205

0-18

0-21

MnO

024

0-50

Specific gravity ....

99-87

100-44

2-95

3-44

1. Amphibolite, Iron Mask Mineral claim, south of
Mill hill, Esquimalt district. M. F. Connor, analyst.

2. Garnet-diopside-epidote rock, Iron Mask Mineral
claim, Mill hill, Esquimalt district. M. F. Connor, analyst.

The Sutton formation is composed of crystalline lime-
stone or marble, occurring as lentils intercalated in the
Vancouver volcanics throughout their entire thickness.
The lentils are small, only one of them, namely that extend-
ing from Esquimalt harbour west to Colwood plain, being
over a mile long. The crystalline limestones are gray to
grayish blue to white, compact to medium grained, and

298

where unmetamorphosed are composed almost entirely
of calcium and magnesium carbonates, the former greatly
predominating. The only impurities are small amounts
of argillaceous and carbonaceous matter and pyrite. Near
the intrusive granitic rocks the Sutton limestones have
been contact metamorphosed into light coloured, coarsely
crystalline marbles carrying diopside and wollastonite,
and even into garnet-diopside-epidote rocks and silicified
and mineralized varieties.

The following analysis is of a sample of limestone from
Rosebank Lime Company's quarry half a mile west of
Esquimalt harbour by F. G. Wait of the Department of
Mines.

The Sutton limestones and Vancouver volcanics are in
general contemporaneous and conformable, the limestones
probably having been built by marine organisms that
lived on the shores of volcanic islands formed during the
eruption of the Vancouver volcanics. However, the actual
contacts between the two formations are intrusive, the
volcanics cutting the limestones. The intrusive contacts,
which are also observed between the volcanic rocks them-
selves, do not indicate that the limestones are an older
formation or necessarily occur near the base of the Vancou-
ver volcanics, but merely indicate that intrusive volcanic
types occur intermingled with the limestones as well as
with one another.

The Vancouver volcanics and Sutton limestones have been
greatly deformed, doubtless largely during the upper
Jurassic orogenic period. The general strike of the rocks,
which on account of their massive character were, for the
greater part, presumably warped into large folds, is about
N. 8o° W., and the dips are usually steep. The original
bedding of the rocks is almost completely obscured, but
the rocks are foliated, and the foliation and bedding appear

CaC03

MgC03

Fe203+Al203

Insol

95-35
2-85

0- 16

1- 95
tr.

tr.

100-31

299

to be virtually conformable. In some instances the
foliation is nearly north to south, which indicates that small
folds occur. The rocks have also yielded by fracturing,
shearing, and faulting.

During and following the upper Jurassic orogenic period,
the Vancouver volcanics and Sutton limestones were
invaded by granitic rocks and their accompanying minor
intrusives, and at the contacts the volcanics were greatly
shattered, cut by apophyses, and, as mentioned, greatly
metamorphosed. The granitic rocks may be subdivided
into three main types, irrupted in a definite sequence as
follows: Wark gabbro-diorite gneiss; Colquitz quartz-
diorite gneiss; and Saanich granodiorite. The minor in-
trusives, most of which accompanied the irruptions of the
Saanich granodiorite, consist of dykes and small injected
bodies of diorite porphyrites.

Batholithic and minor intrusives.

The Wark and Colquitz gneisses form virtually a single
batholith, with a general northwest-southeast strike, cor-
responding with the strike of the Vancouver volcanics.
The Wark gneiss is a dark greenish rock of medium to
coarse grain and gneissic texture, consisting essentially of
light greenish weathering plagioclase (labradorite-
andesine) and hornblende, and since it is intermediate in
composition between a gabbro and a diorite is classed as a
gabbro-diorite. The following is an analysis of a typical
sample.

Si02 48-68

AI2O3 18-05

Fe203 3*41

FeO 6-44

MgO 2-82

Ca O 10 -oo

Na20 3- 18

K20 i-6o

H2 0+ 2-40

Ti02 o-8o

P205 2-01

Mn O 0-20

99*59

Specific gravity 2-91

300

Wark gabbro-diorite gneiss. One half mile south of Mt.
Tolmie, Victoria district. M. F. Connor, analyst.

Fine grained phases of the Wark gneiss occur as segre-
gations or inclusions in the normal rock, especially near
the contacts with the intrusive Colquitz gneiss and Saanich
granodiorite. In places they form bands parallel to the
foliation, but more commonly they form irregularly shaped
masses sometimes several yards in width, which fre-
quently are elongated in a direction transverse to the
foliation. The normal gabbro-diorite is not only gneissic
but considerably altered and more or less metamorphosed,
especially near the contacts with younger granitic rocks,
where there have been developed certain metamorphic
varieties with large and frequently poikilitic hornblendes
or varieties in which recrystallized hornblende greatly
predominates.

The Colquitz gneiss is a gray, medium grained rock of
gneissic to schistose texture, consisting essentially of al-
tered plagioclase (andesine), quartz, hornblende, and
biotite, and is classed as a quartz diorite although it
contains much more quartz than the average quartz
diorite. At one locality the gneiss is a biotite granite.
The Colquitz gneiss has also certain salic and femic facies.
The salic facies is light coloured, consisting essentially
of quartz and feldspar, while the femic facies is dark,
consisting almost entirely of hornblende, thus forming
hornblendites. The facies commonly occur interbanded, the
separate bands or masses varying from a fraction of an
inch up to several feet in width, thus producing a con-
spicuously banded gneiss. The larger femic bands are
virtually always coarsely crystalline.

The following analyses are of the Colquitz gneiss: —

Si 02

64 • 04

75-02

38-80

A1202

15-83

13-90

12-50

Fe203

2-l6

o-45

6-57

Fe 0

2-40

0-40

8-20

Mg 0

2 • 72

o- 10

13-10

CaO

3-60

116

11-42

Na20

3-52

3-°6

1 -6o

K20

i-43

5-37

o-8i

H20 +

1 -6o

o-95

2-85

Ti 02.. ...

0-30 I

0 • 04

1 -6o

30i

P2 05 1-56 0-15 1-26

Mn 0 0-15 o- 10 0-23

99-31 100-70 98-94

Specific gravity 2-74 2-63 3-16

1. Unhanded Colquitz quartz-diorite gneiss, Smiths
Hill, Victoria district. M. F. Connor, analyst.

2. Salic facies of Colquitz gneiss, north of Prospect lake,
Lake district. M. F. Connor, analyst.

3. Coarse grained facies (hornblendite) of Colquitz gneiss.
Northwest of Prospect lake, Lake district. M. F. Connor,
analyst.

The youngest granitic rock, the Saanich granodiorite,
forms a stock underlying the southwestern part of Esqui-
malt peninsula, and other smaller stocks. It is a light
coloured, medium-grained rock, frequently having a some-
what gneissic texture and consisting essentially of feldspar,
orthoclase and andesine, quartz, and accessory hornblende,
and usually biotite. The granodiorite contains also num-
erous small rounded segregations, darker coloured than
the normal rock and consisting chiefly of plagioclase and
hornblende. An analysis of a rather basic phase of the
Saanich granodiorite is given below.

Si 02 62-64

AI2O3 17-75

Fe2 03 1-64

Fe 0 3-44

MgO 2-53

Ca 0 4-44

Na20 3-53

K20 2-14

H20 + ..... 1-65

Ti 02.. ....... . o-6o

P2 05 0-25

Mn 0 0-14

100-75

Specific gravity. ....... 2-71

302

Saanich granodiorite, south shore of Shoal harbour,
North Saanich district, M.F. Connor, analyst.

The diorite porphyrites usually form fairly well defined
and regular dykes, from a few inches up to 50 feet (15 m.)
in width, largely confined to the vicinity of the contacts
of the Esquimalt stock. They are greyish green, porphy-
ritic rocks, with an aphanitic groundmass and phenocrysts
of feldspar, hornblende, and sometimes augite.

All of the irruptive rocks have been more or less foliated,
the gneisses greatly. The strike of the foliation is predomi-
nantly northwest-southwest, generally near N. 6o° W,
but varies widely. The rocks are also greatly jointed and
fractured, and in places sheared. They are altered and,
especially near the shear zones, are mineralized and cut
by small and irregular quartz and quartz-epidote veins,
but contain no mineral deposits of commercial value.

Although the Wark and Colquitz gneisses form virtually
a single batholith, the Colquitz gneiss is distinctly intrusive
into the Wark gneiss, the contacts being marked by wide
zones of shatter breccias and numerous aplitic and a few
pegmatitic apophyses of the Colquitz gneiss. Although
in places cross cutting, the apophyses are usually injected
parallel to the foliation, and are foliated themselves par-
allel to their walls. In some instances the apophyses,
parallel to the foliation, are so numerous as to convert the
gabbro-diorite gneiss into a banded gneiss resembling the
banded Colquitz gneiss. Also the Wark gneiss is cut by
large masses of the Colquitz gneiss, usually the salic facies,
some of which are several hundred feet in width. The
contact zones are sometimes sheared and foliated and the
angular xenoliths of the gabbro-diorite gneiss in the quartz
diorite gneiss have been pulled out into dark femic bands
These strongly resemble the femic bands of the Colquitz
gneiss, but in part perhaps differ from them by being occa-
sionally broken or cut across the foliation by the quartz
diorite. The relatively few dykes of pegmatite are unfol-
iated, and, while usually parallel to the foliation, are
sometimes cross cutting.

The banded Colquitz gneiss, in particular that type
with the wide, coarse grained, femic bands or masses, is
more or less restricted in its occurence to the contacts
with the intruded Wark gneiss. As described, its salic
and femic bands vary in didth from a fraction of an inch
to 4 or 5 feet (1 -2 or 1-5 m.), and possibly to several feet.

303

The length of the individual bands is more or less propor-
tional to their width. Some of the bands, especially the
narrower and finer grained, gradually pinch out, but others,
notably the wider, coarser grained ones, end abruptly and
irregularly. The sides of the bands are usually straight but
are sometimes broadly curved and more rarely contorted.
The contacts between the bands, while usually well marked,
are not sharp in detail, but the crystals of one band are
intergrown with those of the continuous bands. In places
the Wark gneiss appears to be cut not only by salic
apophyses of the Colquitz gneiss but by hornblendite
apophyses, which seem to be intrusive and cross cutting.
The relations however are so complex and the resemblance
of the supposed hornblendite apophyses to the recrystallized
Wark gneiss is so close that the intrusive nature of the
hornblendite masses can not be positively affirmed. It is
concluded that the banded Colquitz gneiss is of primary
origin ; that in part the salic and femic bands are true mag-
matic differentiates, the intrusive magma having been split
into the salic and femic facies before it became too viscous for
the separated facies to be pulled out into bands by continued
movements in the differentiated magma; and that some
of the wide, coarser grained bands are recrystallized and
pulled out inclusions of the Wark gneiss.

The Saanich granodiorite is clearly intrusive into the
Wark gneiss and doubtless is younger than the Colquitz
gneiss. It brecciates the Wark gneiss, forming extensive
areas of "contact complex", consisting of shatter breccias
and networks of granodiorite and aplite apophyses in the
gabbro-diorite gneiss.

The diorite porphyrites are younger than the granitic
rocks. It is seen that the eruptive cycle, represented by
all of the igneous rocks, the Vancouver meta-volcanics,
the granitic rocks, and the diorite porphyrites, conforms to
the general eruptive cycle, which consists of three phases
of igneous activity in the following sequence : the volcanic
phase; the batholithic phase; and the phase of minor
intrusives.

The granitic rocks were irrupted into the rocks of the
Vancouver group apparently in a relatively quiet manner,
and have replaced them without disturbing them greatly.
The invading magmas, even during their last active stages,
shattered the invaded rocks along their contacts into
angular fragments. Near the present contacts great

304

numbers of these fragments occur in the intrusive rocks
but disappear within a few yards. They may have been
shattered to smaller fragments and assimilated by the
intrusive rocks while still in a magmatic condition, for of

Contact shatter breccia at contact of Wark gabbro-diorite gneiss and Saanich
granodiorite, showing both angular and rounded xenoliths; ledge south
of Outer wharf, Victoria.

this there is some evidence, or they have sunk in the intrus-
ive magma to abyssal depths. Possibly it was by this last
method that the granitic rocks replaced large volumes of
the rocks into which they were intrusive.

As described, the granitic rocks were not irrupted at
the same time, but during two main periods, which have

305

been called the Wark and Saanich periods. During the
first period, the Wark and Colquitz gneisses were irrupted,
but independently, thus dividing the Wark period into
two sub-periods, the second sub-period being characterized
by the irruption of a more salic magma than that irrupted
during the first. The close relationship of the Wark to
the Colquitz gneiss shows, however, that they are closely
related in origin, and are doubtless differentiates of the
same parent magma. A similar subdivision characterizes
the Saanich irruptive period, but the first sub-period,
during which the femic Beale diorite was irrupted, is not
well represented near Victoria. Also the rocks irrupted
during the Wark and Saanich periods are closely related
structurally, and, except that those of the Wark period are
gneissic, are similar lithologically. It is probable, there-
fore, that the Wark and Saanich magmas were themselves
differentiates of the same parent magma, the Wark magma
being more basic then the Saanich magma. Since the
principal rock types have been separately, and more or
less independently, intruded in large masses, the differ-
entiation producing the various types must have been
deep seated. Since the parent magma was apparently
subdivided into the Wark and Saanich magmas, each of
which independently underwent further differentiation
under deep seated conditions, it seems probable that this
differentiation did not take place in the same magma
chamber. It looks as if the Wark and Saanich magmas
after differentiation from the parent magma were irrupted
from the primary magma chamber into separate chambers,
where each underwent its further differentiation, producing
the sub-types which were themselves irrupted independ-
ently into their present position. It also appears as if the
three principal types were still further differentiated,
apparently "in place", giving rise to the minor variations
of the principal rock types.

Metchosin volcanics. — Confined to the western part
of the region and separated from the other crystalline rocks
by the thick deposit of sand and gravel of the Colwood
delta, are the Metchosin volcanics. They are all basic,
chiefly basalts and diabases, the latter occurring as dykes
in the basalts. The basalts vary from coarsely porphy-
ritic and ophitic varieties to amygdaloids, and frequently
exhibit pillow and columnar structures. They are inter-
bedded with fragmental varieties, ranging from fine tuffs

307

to very coarse agglomerates. Some of the fragmental
rocks are waterworn, and at least one bed of tuff is fossili-
ferous. The fossils, which are chiefly Eocene gastropods,
give the only evidence of the age of the volcanics and
place them definitely in the upper Eocene. The same
fossil-bearing tuffs are found to the south on the Olympic
peninsula [14]. It is probable that the eruptions of
the Metchosin basalts were largely of a quiet nature from
numerous fissures, and actual vents are doubtless repre-
sented by diabase dykes. That the eruptions were in part
explosive is fully substantiated by the occurrence of agglo-
merates and tuffs, and it is possible that the irregular
masses of coarse agglomerate represent the pipes or necks of
old volcanic cones. The absence of terrestial sediments
in the volcanics and the presence of marine organisms
suggests that the volcanics were accumulated under
marine conditions, presumably in deep water removed
from any continental mass. But the occurrence of water-
worn fragments and of marine fossils indicates that enough
lava was erupted to form a platform which reached nearly
to the surface of the water, and on which were built the
cones that projected above sea level.

The Metchosin volcanics have been deformed and more
or less altered. They have a general northwest-
southeast strike and are evidently involved in several
folds although the prevailing dip is about 30 degrees to
the northeast. They are extensively sheared and faulted,
and their northern contact is a profound thrust fault,
which extends for 40 miles (64 km.) across the southern
end of the island. Farther west they are also intruded by
gabbro masses. The deformation and intrusion must
have taken place at or near the close of Eocene times, for
farther west the deformed and intruded rocks are uncon-
formably overlain by Miocene sediments. Some of the
alteration of the Metchosin volcanics must have taken
place during the deformation, but much of it has taken
place under surface conditions developing zeolites and
similar secondary products.

Superficial Deposits — The drift deposits of the region
are of varied character, having been deposited by various
agencies during the different stages of glacial occupation
and retreat [7 and 8]. The oldest of the superficial
deposits, the Admiralty till, is confined to a few localities
and occurs in the crevices and small irregular hollows of
35069— 3B

3o8

the glaciated crystalline rocks, and is only a few feet in
thickness. It varies from an unstratified, hard, yellowish
gray, sandy clay, with subangular to rounded pebbles,
to rudely stratified, coarser, yellow clayey sand, with
scattered pebbles and subangular boulders.

The Puyallup inter-glacial deposits are chiefly well
stratified clays, sands, and gravels usually found below
elevations of 250 feet (76 m.) In general, the clays
occur near the base of the deposits, and the sands and
gravels near the top, so the deposits are subdivided into
the Maywood clays and the Cordova sands and gravels.
The Maywood clays are chiefly bluish or yellowish
gray, sandy clays with numerous, irregularly distributed,
subangular to rounded, undecomposed pebbles and boulders
of crystalline rocks. They are well stratified and fre-
quently contain layers of sand and occasionally of gravel.
The clays are frequently carbonaceous, and plant
impressions and remains are common in them.
Impressions and occasional shells of marine organisms,
chiefly small molluscs, are also found in them. The
Maywood clays sometimes rest upon the Admiralty till,
but more commonly lie directly on glaciated surface of the
crystalline rocks. They vary greatly in thickness,
depending partly upon the irregularities of the underlying
rock surface, but they probably average as much as
100 feet (30 m.).

The Cordova sands and gravels consist of yellow to
grayish yellow, medium to coarse grained, and usually
pebbley sand, with irregular lentils and interbeds of
gravel, and towards the base, interbeds sometimes 10 to
15 feet (3 to 4-5 m.) thick of sandy clay or rarely stiff
blue clay. They also contain a few, irregularly distributed,
small glacial boulders. The pebbles are usually fresh,
but in some instances the coarser grained granitic pebbles
have been entirely decomposed. The sands are well
stratified, but are usually cross bedded, and exhibit instances
of contemporaneous erosion and deposition. They also
contain marine organisms, which are however very
fragile. The Cordova sands and gravels, averaging 200 feet
(65 m.) in thickness, overlie the Maywood clays, and
usually form low ridges that were left in relief by the
erosion of wide valleys between them by glaciers of the
Vashon period Some of the ridges occur in the lea of
the larger monadnocks.

309

The Vashon drift is ordinarily an unsorted till, with
numerous undecomposed granitic boulders. In some
places the finer materials of the drift are rudely stratified.
Near the surface it is usually oxidized to dark brown,
and passes into a dark, sandy and gravelly loam, which
usually covers it. The drift seldom forms distinct and
characteristic topographic features such as moraines,
but is merely a mantle covering the crystalline rocks and
the inter-glacial deposits. Below elevations of 250 feet
(80 m.) except in restricted localities, the mantle is thin,
seldom more than 3 or 4 feet (-9 to 12 m.) thick. Fre-
quently it thins out so completely that over large areas it is
absent or is represented only by glacial boulders, which
are strewn over the surface of the inter-glacial deposits.
Above elevations of 250 feet, (80 m.) the larger part of
the entire drift mantle is the Vashon till, although it is
probably mixed with more or less of the Admiralty till.

In the western part of the region is a deposit of sand
and gravel about 200 feet (60 m.) thick, which forms a
plain, the smooth Colwood plain, two to three miles (3 to
5 km.) wide and from 200 to 250 feet (60 to 80 m.) above
sea level. On it are well defined terraces up to 20 feet
(6 m.) high, and near its inner border are several kettle
holes, the largest of which are 100 to 800 feet (30 to 250 m.)
across and 10 to 80 feet (3 to 25 m,) deep. The deposit
consists chiefly of coarse sands and gravels, which are well
stratified and have a pronounced delta structure, the
larger part of the deposit consisting of fore-set beds with
dips of 15 to 25 degrees to the southeast. These are capped
with 10 to 15 feet (3 to 5 m.) of top-set beds of horizontally
stratified coarse gravels.

Since the superficial deposits described above are of
glacial origin a discussion of their origin together with a
description of the glaciation of the region is necessary.
The lowland portion of the region was overridden by the
southward flowing, piedmont, Strait of Georgia glacier.
The results of the severe abrasion of the hard rocks by the
glacier are most striking [7]. The rocks are not only
smoothed, but are striated and grooved, the grooves even
in the crystalline rocks attaining a width of 3 to 5 feet
(•9 to 1-5 m.) and a depth of 1 to 5 feet (-3 to 1-5 m.).
The striations and grooves are not confined to the flat
surfaces, but occur also on the sloping and vertical ones,
in some instances the rocks being actually undercut.
35069— 3^B

3io

These features, and curved and spreading striations, indi-
cate the remarkable ''plasticity" of ice under great pres-
sure. The smaller ledges have been worn into roches
moutonnees, and although their lea ends are usually broad
and craggy, they are in places smoothly polished and
striated. The abrasion has been greatest on the soft rocks,
and has left rounded ledges of the hard rocks in relief.
Many of the rounded points of the shore line are of this
nature. The general direction of movement seems to have
been slightly west of south. Locally, owing to the influ-
ence of topography, the movement appears to have varied
considerably from this direction. The influence of the
topography varied at successive stages of glaciation, and
as a result cross striations were produced. The direction
of the grooves varies only from 10 to 20 degrees from south,
but that of the striations, which frequently cross the
grooves and are later, varies at least from S. 500 E. to S.
350 W. This fact indicates that the minor topographic
features had little effect on the glacial movement until
the stage of glacial retreat. The only superficial deposit
formed during this period of glaciation is the Admiralty
till. It was doubtless more extensive than appears at
present, and probably furnished a large part of the material
of the inter-glacial deposits and, as mentioned, may occur
on the upland mingled with the Vashon drift. It was
deposited directly by ice, some of it being clearly a ground
moraine, but part of it was apparently deposited in water,
probably below sea-level.

On the retreat of the Admiralty glaciers the land stood
at least 200 feet (60 m.) lower than at present, since marine
fossils occur in the inter-glacial deposits up to that eleva-
tion. Presumably the drowned pre-Glacial lowland formed
estuaries, and in these estuaries, under conditions of
comparative quiet and of moderate temperature, the May-
wood clays were deposited. The glaciers had not, how-
ever, completely disappeared from the region as the
irregularly distributed pebbles and large erratic glacial
boulders in the clays testify, since they were doubtless
dropped from floating ice. During the later stages of the
inter-glacial epoch, when the Cordova sands and gravels
were being deposited, either shallower water prevailed
or else the rivers and streams issuing from the ice front,
perhaps advancing at this time, were more heavily laden
with coarser detritus.

3ii

During the epoch of Vashon glaciation, the Vashon
drift was deposited largely by ice alone, but doubtless in
part by water. The Vashon galciers were smaller than those
of the Admiralty period, for the Vashon drift rests directly
upon the hard glaciated rocks in the upland regions only,
since the piedmont glaciers, which over-rode the lowland,
were unable to remove the covering of inter-glacial deposits,
eroding merely portions of these deposits.

To judge from the absence of moraines of Vashon drift,
the retreat of the Vashon glaciers must have been fairly
rapid. Nevertheless the Col wood delta was doubtless
formed at the front of one or more of the retreating glaciers,
presumably in salt water. This delta has since been up-
lifted about 250 feet (80 m.).

Particular Descriptions.

Excursion C 1. (First Day).

From the Empress hotel the route of the excursion lies
along the shore south of Victoria to Oak bay and across
the cities of Oak Bay and Victoria, stops being made at
various points of interest.

Locality 1. — Contact shatter-breccia of Wark gabbro-
diorite gneiss and Saanich granodiorite, cut by complex
of diorite porphyrite dykes. Minor faulting. Glacial scour-
ing, roches moutonnees, deep grooves, and stria tions.
General view of contraposed shore-line.

Locality 2. — Good view to the east of an irregular
rocky (contraposed) shore line. Hard rocks overlain by
retrograded Vashon drift and Maywood clays.

Locality 3. — Contact complex and shatter breccia
of Vancouver meta-andesite, Wark gabbro-diorite gneiss,
and Saanich granodiorite. Aplitic apophyses with quartz
segregations and quartz veinlets. Hybridism. Breccia
foliated and slightly faulted. Glacial grooving and stria-
tion. East to Clover point, submaturely retrograded
portion of shore line. Clover point, hard rock headland
showing beginning of contraposition.

Locality 4. — Between 3 and 4 pre-Glacial lowland
covered by Maywood clays with a thin mantle of Vashon
drift and frequent outcrops of Vancouver meta-volcanics.
To the south Gonzales hill, altitude 215 feet (65 m.) a
monadnock surmounting the lowland.

312

Vancouver meta-volcanics, foliated flow-breccia. Roches
moutonnees, grooving, and crossed striations.

Locality 5 — Between 4 and 5 pre-Glacial lowland of
Maywood clays with thin mantle of Vashon drift and
numerous outcrops of Vancouver meta-andesites.
Foliated, contact metamorphosed Vancouver volcanics,
cut by a great number of quartz-feldspar masses and
irregular apophyses of quartz-diorite.

Locality 6. — Contact complex of Vancouver meta-an-
desites and Wark and Colquitz gneisses. Hybridism and
primary gneisses.

Locality 7 — Between 6 and 7 pre-Glacial lowland with
small glaciated monadnocks and ledges chiefly of Wark
gabbro-diorite gneiss.

Road-cut in drift, showing relations of Admiralty till,
Maywood clays, and Vashon till.

Excursion C 1 (Second Day).

From the Empress hotel the route of the excursion lies
north and west of Victoria to a number of points of geolo-
gical interest.

Locality 8 — Vashon drift, unconformably overlying
Cordova sands and gravels, which overlie Maywood cla\ rs.
Latter not exposed here. Sand and gravel pits, from which
material is obtained for mortar, concrete, filling, etc.

Locality 9 — Between 8 and 9, pre-Glacial lowland
largely covered by Maywood clays, few outcrops of Wark
and Colquitz gneisses.

Mt. Tolmie, altitude 383 feet (95 m.), a monadnock
of Wark gabbro-diorite gneiss, protected the Cordova
sands and gravels from erosion during Vashon glaciation.
Section of drift and Cordova sands and gravels. Sand
and gravel bank.

Locality 10 — Between 9 and 10 pre-Glacial lowland
with numerous small monadnocks and large ledges, chiefly
of Wark gneiss.

View of wooded "train" of Cordova sands and gravels
in lea of large monadnock, Mt. Douglas or Cedar hill,
altitude 725 feet (220 m.).

Locality 11 — From 10 along wooded "train" of Cordova
sands and gravels to top of Mt. Douglas.

Wark gabbro-diorite gneiss, cut by aplite veins. General
view of pre-Glacial lowland, uplifted Tretiary peneplain —

313

the Vancouver Island upland — , Pacific Coast and Juan de
Fuca downfolds, and Coast range and Olympic mountains.

Locality 12 — From n to 12 across pre-Glacial lowland
with numerous ledges of Wark and Colquitz gneisses.

Sharp contact of Wark and Colquitz gneisses. Coarse
grained, recrystallized phases, and fine grained segrega-
tions of Wark gabbro-diorite. Pegmatite dykes. Foliation.
Glacial grooves, striations, and roche moutonnee.

Locality 13 — From 12 south to Victoria and across
Esquimalt peninsula, pre-Glacial lowland with numerous
small monadnocks or ledges of the crystalline rocks, but
largely covered by Maywood clays with a thin mantle of
Vashon drift in places. To east and west of Esquimalt
peninsula the drowned submaturely glaciated valleys of
Victoria and Esquimalt harbours. To northwest, upland,
formed by late mature dissection of uplifted Tertiary
peneplain, transitional in character to the Vancouver
Island upland.

Quarry in Sutton limestone. Limestone used for flux
by Tyee Copper Company's smelter at Ladysmith. Dyke
of sheared basalt porphyrite of Vancouver volcanics.

Locality 14 — Sutton limestone lens in contact with
Saanich granodiorite. Apophyses of granodiorite and
irregular dykes of basalt porphyrite. In places limestone
contact metamorphosed, silicified, and converted into
garnet-diopside-epidote rock, with small body of magnetite
and chalcopyrite. Limestone quarried for manufacture of
lime.

Locality 15 — Between 14 and 15, Colwood delta.

Section of Colwood delta showing top-set and fore-set
beds. Hydraulicking of deposit for sand and gravel, used
for concrete, filling, etc.

Locality 16 — From 15 across Colwood delta and Albert
head. Headland composed of Metchosin volcanics.

Metchosin basalts. Tuffs and agglomerates, some with
water worn fragments, "concretions," and "bombs."
Vesicular and amygdaloidal basalts. Diabase dykes and
pipes. Denuded volcano (?). Columnar jointing. Fossili-
ferous tuffs (upper Eocene gastropods) . Secondary minerals,
calcite, quartz, and zeolites. Glacial grooves, striations,
and roches moutonnees.

Locality 17 — Metchosin basalts, columnar jointing and
pillow structure.

Locality 18 — From 17 back on to Colwood delta.

314

Kettle or ice block holes near inner border of delta.
Large ledges of Metchosin basalts to west.

Locality 19 — From 18 across terraced Colwood delta.

Iron Mask mineral claim on south slope of Mill hill,
altitude 631 feet (195m). Contact metamorphosed Van-
couver andesites, amphibolites, which have been sheared,
solicified, and mineralized, cut by quartz veinlets, and
replaced by garnet-diopside-epidote rock, with magnetite,
pyrrhotite, pyrite, and chalcopyrite.

Locality 20 — To the west Sutton limestone quarried
for the manufacture of lime. Lime hydrated and used in
the manufacture of sand-lime brick. Sand from Colwood
sands and gravels.

Locality 21 — Unfoliated shatter breccia of Wark and
Colquitz gneisses. Hybridism and development of horn-
blendite.

Locality 22 — Banded Colquitz quartz diorite gneiss,
primary gneiss. Small pegmatite dykes, small faults and
contortions.

Locality 23 — From 22 over pre-Glacial lowland. Nu-
merous ledges of Wark gneiss and small monadnock,
Knocken hill, to north, altitude 260 feet (79 m.), and
drowned glaciated valley, Portage inlet, to south.

Pot-hole in Wark gabbro-diorite gneiss, formed by glacial
stream descending through a crevasse or by inter-glacial
stream. Wark gneiss cut by apophyses of Colquitz quartz
diorite.

Locality 24 — From 23 over pre-Glacial lowland, largely
covered by Maywood clays with thin mantle of Vashon
drift in places, and a few outcrops of Wark gneiss.

Maywood clays. Clays used for the manufacture of
common brick and tile. Marine fossils.

Excursion C 2 (Section I.)

From the Empress Hotel the excursion proceeds west
across the Esquimalt peninsula, which is a portion of the
pre-Glacial lowland, with numerous small monadnocks or
ledges of the crystalline rocks, largely covered by Maywood
clays, with a thin mantle of Vashon drift in places.
To the east and west of Esquimalt peninsula the
drowned submaturely glaciated valleys of Victoria and
Esquimalt harbours. To northwest, upland formed by

315

late mature dissection of uplifted Tertiary peneplain,
transitional in character to the Vancouver Island upland.

Locality 1 — Quarry in Sutton limestone. Limestone
used for flux by Tyee Copper Company's smelter at
Ladysmith. Dyke of sheared basalt prophyrite of
Vancouver volcanics.

Locality 2 — Sutton limestone lens in contact with
Saanich granodiorite. Apophyses of granodiorite and
irregular dykes of basalt porphyrite. In places limestone
contact metamorphosed, silicified, and converted into
garnet-diopside-epidote rock, with small body of magnetite
and chalcopyrite. Limestone quarried for manufacture
of lime.

To the southwest, Sutton limestone quarried for the
manufacture of lime. Lime hydrated and used in the
manufacture of sand-lime brick. Sand from Colwood
sands and gravels.

Locality 3 — From 2 across Colwood delta.

Section of Colwood delta showing top-set and fore-set
beds. Hydraulicking of deposit for sand and gravels, used
for concrete, filling, etc.

Locality 4 — From 3 across Colwood delta and Albert
head. Headland of Metchosin volcanics.

Metchosin basalts. Tuffs and agglomerates, some with
water worn fragments, "concretions", and "bombs".
Vesicular and amygdaloidal basalts. Diabase dykes and
pipes. Denuded volcano (?). Columnar jointing. Fossili-
ferous tuffs (upper Eocene gastropods). Secondary
minerals, calcite, quartz, and zeolites. Glacial grooves,
striations, and roches moutonnees.

Locality 5 — Metchosin basalts, columnar jointing and
pillow structure.

Locality 6 — From 5 back on to Colwood delta.

Kettle or ice block holes near inner border of delta.
Large ledges of Metchosin basalts to west.

Locality 7 — Unfoliated shatter breccia of Wark and
Colquitz gneisses. Hybridism and development of horn-
blendite.

Locality 8 — Banded Colquitz quartz diorite gneiss,
primary gneiss. Small pegmatite dykes, small faults and
contortions.

Locality 9 — From 8 over pre-Glacial lowland.
Numerous ledges of Wark gneiss and small monadnock,
Knockan hill to north, altitude 260 ft. (79 m.), and drowned
glaciated valley, Portage inlet to south.

3i6

Pot hole in Wark gabbro-diorite gneiss, formed by-
glacial stream descending through a crevasse, or by inter-
glacial stream. Wark gneiss cut by apophyses of Colquitz
quartz diorite.

Locality 10 — From 9 over pre-Glacial lowland, largely
covered by Maywood clays with thin mantle of Vashon
drift in places and a few outcrops of Wark gneiss.

Maywood clays. Clays used for the manufacture of
common brick and tile. Marine fossils.

Excursion C 2, (Sections I and II).

Leaving the Empress hotel the entire excursion proceeds
along the shore south of Victoria to Oak bay, stopping at
various points of interest, and then returns to Victoria, via
Mt. Tolmie.

Locality 11 — Contact shatter breccia of Wark gabbro-
diorite gneiss and Saanich granodiorite, cut by complex of
diorite porphyrite dykes. Minor faulting. Glacial
scouring, producing roches moutonnees, deep grooves, and
striations. General view of contraposed shoreline.

Locality 12 — Good view to the east of an irregular
rocky, contraposed shore line. Hard rocks overlain by
retrograded Vashon drift and Maywood clays.

Locality 13 — Contact complex and shatter breccia of
Vancouver meta-andesite, Wark gabbro-diorite gneiss, and
Saanich granodiorite. Aplitic apophyses with quartz
segregations and quartz veinlets. Hybridiom.

Breccia foliated and slightly faulted Glacial grooving
and striation. East to Clover point, submaturely retro-
graded portion of shore line. Clover point, a hard rock
headland, showing beginning of contraposition.

Locality 14 — Between 13 and 14 pre-Glacial lowland
covered by Maywood clays with a thin mantle of Vashon
drift and frequent outcrops of Vancouver meta-volcanics.
To the south Gonzales hill, altitude 215 feet (65 m.), a
monanock surmounting the lowland.

Vancouver meta-volcanics, foliated flow-breccia. Roches
moutonnees, grooving, and crossed striations.

Locality 15 — Between 14 and 15 pre-Glacial lowland
of Maywood clays with thin mantle of Vashon drift and
numerous outcrops of Vancouver meta-andesites. Foliated,
contact metamorphosed Vancouver volcanics, cut by a

317

great number of quartz-feldspar masses and irregular
apophyses of quartz diorite.

Locality 16 — Contact complex of Vancouver meta-
andesites and Wark and Colquitz gneisses. Hybridism
and primary gneisses.

Locality 17 — Between 16 and 17 across pre-Glacial
lowland largely covered by Maywood clays, few outcrops
of Wark and Colquitz gneisses.

Mt. Tolmie, altitude 383 feet (95 m.), a monadnock of
Wark gabbro-diorite gneiss cut by pegmatite and aplite
dykes and quartz veins. Grooving and striations.
Cordova sands and gravels in lea of monadnock protected
from erosion during Vashon glaciation. Section of Vashon
drift and Cordova sands and gravels. Sand and gravel
bank. General view of pre-Glacial lowland and uplifted
Tertiary peneplain — the Vancouver Island upland — ,
Pacific Coast and Juan de Fuca downfolds, and Coast
range and Olympic mountains.

Locality 18 — From 17 to 18 pre-Glacial lowland largely
covered by Maywood clays, few outcrops of Wark and
Colquitz gneisses.

Vashon drift, unconformably overlying Cordova sands
and gravels, which overlie Maywood clays, Latter not
exposed here. Sand and gravel pits. Sand and gravel
used for mortar, concrete filling, etc.

ANNOTATED GUIDE.
(Vancouver to Nanaimo.)
Excursion C 2, Section II.

Miles and
Kilometres.

o m. Vancouver — Leaving Vancouver the steamer

o km. sails westward through the narrow pass called
the First Narrows, at the entrance of Vancouver
harbour, into the Strait of Georgia. To the
north are the lower mountains of the Coast
range, composed largely of granitic rocks, and
to the south is the low area underlain by the
relatively unresistent Eocene sediments, con-
sisting largely of sandstones and conglomerates,
only moderately disturbed, and well exposed in

3i8

Kiiomefres ^e sh°re cliffs W- The Eocene sediments are
almost entirely covered with the thick deposit
of clay, sand, and gravel comprising the Fraser
River delta, built largely in post-Glacial times
and recently uplifted some 400 feet (120m.)
and cliffed during the present marine cycle, so
that the old delta appears conspicuously to the
south as the steamer sails west across the open
waters of the Strait of Georgia. The present
delta of the Fraser forms an extensive lowland,
only a few feet above sea level, that extends
south from the older, uplifted delta.

To the west is Vancouver island. In clear
weather a good general view of it may be had.
The dark mass of the Vancouver range, composed
largely of metamorphic and crystalline rocks,
steeply surmounts the coast lowland which is
underlain by the less resistant sediments of the
Nanaimo series. Most of the summits are
rounded or ridge-like, but a few snow capped
and serrated peaks are seen crowning the whole.

After crossing the Strait of Georgia, the
steamer enters Fairway channel between En-
trance and Gabriola islands to the south and
Snake island to the northwest. These islands
are built of the upper formations of the Nanaimo
series, which are here involved in a large syn-
cline pitching to the north. Turning south,
the steamer sails along a drowned valley largely
underlain by shales, between sandstone islands,
Gabriola island to the east and Newcastle and
Protection islands to the west. Rounding the
southern point of Protection island, on which
is seen the surface workings of the Protection
shaft of the Western Fuel Company's collieries,
the steamer enters Nanaimo harbour. Directly
to the west is the city of Nanaimo,
41 m. Nanaimo — built on the coastal lowland of sedi-
66 km. mentary rocks of the Nanaimo

series. In the background is Mt. Benson, 3,300
feet high (1,000 m.) composed of Vancouver
volcanics, around which the Nanaino series
forms a narrow fringe.

319

GEOLOGY OF THE REGION AROUND NANAIMO.

PHYSIOGRAPHY.

The region around Nanaimo (5) is a part of the east
coast lowland of Vancouver island. Since the sedimentary
rocks underlying the lowland are varyingly resistant,
as well as moderately disturbed, their predominating strike

being northwest and their dip northeast, the lowland has
considerable relief, extensive valleys having been developed
in belts of soft rocks, between ridges composed
of more resistant beds. The hard rock ridges are of the
cuesta type with very steep, in places nearly vertical, front
slopes and gentle dip or back slopes. Tongues of the crys-
talline rocks extend eastward from the upland to the west,
and form low eastward trending ridges increasing in eleva-
tion to the westward. One of the ridges in the northern
part of the region forms the northern boundary of the
sedimentary rock basin, and another west of Nanaimo is

320

the flank of Mt. Benson. It appears as if the eastern
part of the Nanaimo basin had been depressed below sea
level, and the valleys drowned to form the long, wide
channels, passes, and harbours of the region. The hard
rock ridges remain above sea level as long points and islands.
During the Glacial period the region was glaciated, and the
rock surfaces were smoothed, and the valleys deepened.
Upon the retreat of the glaciers the region apparently
stood a few hundred feet lower than at present, for up to
an elevation of 400 feet (120 m) occur stratified sands and
gravels, in part of marine or estuarine origin. A recent
uplift has brought the land into its present position, and
initiated the present erosion cycle, during which the
revived streams have terraced the superficial deposits,
and have cut narrow canyons in the indurated rocks,
while the superficial deposits fronting on the coast have
been retrograded to form cliffs up to 100 feet (30 m.) in
height.

General ceology.

The crystalline rocks, upon which the coal bearing
sediments of the Nanaimo series rest unconformably, are
the Vancouver meta-andesites. The volcanic rocks were
greatly deformed, metamorphosed and intruded by granitic
rocks, probably in late Jurassic time. The granitic rocks
were subsequently exposed, since boulders and pebbles
of them occur in the sediments of the Nanaimo series.
However, the crystalline rocks were apparently not worn
down to a lowland, because the surface upon which the
sedimentary rocks were deposited is seen to be one of
considerable relief. Small irregularities are directly ob-
servable in exposed unconformities, and the contacts of the
Nanaimo series with the underlying rocks, where not dis-
turbed by intense folding and faulting, follow very closely
the contours of present elevations, which must have been
elevations at the time of deposition also, unless far more
irregular and complex folding than is elsewhere observed is
supposed.

The Nanaimo series, as shown by its fauna, is partly
of marine origin, probably estuarine, since it was deposited

321

on a surface of considerable relief, and under varying
conditions, as shown by the rapid lateral and vertical
gradation of the sediments. The series also contains
land plants and coal, probably of fresh water accumu-
lation. Hence conditions of fresh or at least brackish
water, that is, terrestrial conditions, alternated with
marine conditions. The upper part of the Nanaimo series,
however, contains few or no marine organisms, the only
fossils being a few obscure plants. It is possible therefore,
that the alternating conditions recorded in the lower part
of the Nanaimo formation were finally replaced entirely
by terrestrial conditions. The lithological character of
the sediments — the sandstone being composed of angular
to sub-angular fragments and of a large percentage of
easily decomposed minerals such as feldspar — indicates
a very rapid accumulation and deposition in relatively small
basins, where the detritus wTas not subject to severe wave
action. The sedimentation began in Upper Cretaceous
time, at a stage corresponding with the Chico, or the Pierre,
and it appears as if the sediments were first deposited in
a marine basin, between the mainland and Vancouver island,
which basin was probably one of deformation, depressed
at least as early as the upper Jurassic. During the
deposition, the sedimentation trangresscd inland, at
first filling up the irrgularities of the pre-Upper Cretaceous
erosion, and then possibly covering even the higher residual
elevations. The total thickness of the Nanaimo series
was near 10,000 feet (3,000 m.) toward the close of its
deposition, at which time it extended far inland over the
denuded crystalline rocks covering the greater part of
the island, or was perhaps restricted to large depressions.

The conditions of deposition in the northwestern part of
the Nanaimo basin, where the coal deposits occur, appear
to have been more uniform than these which existed else-
where, for there the series may be subdivided solely on a
lithological basis into various formations each with its
more or less peculiar characteristics. The formations are
enumerated and their thickness and general lithological
character given in the following table: —

322

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loo o

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C COCO

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X X c_

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3*3

In general the conglomerates are composed chiefly of
quartz and quartzose rocks; the sandstones chiefly of
granitic detritus, quartz and feldspar; and the shales chiefly
of volcanic detritus, being grayish green in color. From the
mere statement of these facts, which constitute a rather
peculiar feature of the lithology, a simple yet fairly plausible
explanation suggests itself. Of all the underlying rocks
whose detritus composes the sediments, the volcanic rocks
alone were chemically disintegrated, and their detritus,
being very fine grained, was deposited as mud which
now forms the shales. The granitic rocks were mechani-
cally disintegrated, and broken down into a coarse felds-
pathic sand, furnishing the material for the sandstones.
The quartz veins and the quartzose rocks, however, were
broken down only into a coarse rubble to form the material
for the conglomerates.

A peculiar feature of the shale horizons of the upper
part of the Nanaimo series, especially of those characterized
by a large number of small sandstone interbeds, is the
occurrence of numerous sandstone dykes. These cut the
shales at all angles to the bedding. They are fairly
regular, although branching and offset by faults. The
larger, 3 to 4 feet (-9 to 1-2 m.) thick, may be traced for
at least 100 feet (30 m.). Although they cut the shales
sharply, apparently along joint planes, the shales are
frequently bent or slightly contorted next to the dykes.
On the shores, where the dykes are best exposed, on
account of their greater resistance to wave erosion, they
stand above the shales, forming low walls, the highest
wall noted being three feet (9 m.).

As a rule the dykes are finer grained than the sandstone
interbeds, and the cementing material is more calcareous
but in general the two are of similar material. Indeed,
in many instances, dykes protrude from the sandstone
interbeds, and there are off-shoots from the dykes confor-
mable with the bedding of the shales, that simulate the
appearance of sandstone interbeds, but are recognized as
off-shoots by occurring usually on one side of the dyke
only. There are also other smaller and more irregular
off-shoots into the shales, resembling small apophyses
from an igneous dyke.

From their occurrence and close resemblance to other
intrusive sandstone dykes, their origin is in little question.
They appear to have been formed by the injection of soft
35069— 4B

324

sands which were forced usually upward along joint planes
in the shale, the injection being similar to that of an
igneous dyke. After the injection the sands were firmly
cemented by calcium carbonate, precipitated from water
circulating through the relatively coarse grained dyke.
One important conclusion to be drawn from their occurrence
is that movement must have taken place while at least
the upper sandstones of the Nanaimo series were in a soft
and plastic condition.

Another feature indicates that movement took place
while the sediments of the upper part of the series were in
a plastic condition. Even in the coarser, most massive
beds, such as thick bedded conglomerates, sudden folds or
sharp rolls occur, although the beds may be otherwise
only moderately disturbed. These rolls, which are really
more of the nature of small displacements or faults, are so
pronounced that a bed which has a moderate dip in one
direction may turn down at right angles, so that the dip of
the down-turned portion is vertical and its strike is at right
angles to the strike of the bed as a whole. The largest of
these sharp rolls, exposed on the west shore near the
northern end of Newcastle island, occurs in a coarse
grained, thick-bedded conglomerate, and the width of the
down-turned portion is about 150 feet (45 m.). In spite
of the magnitude and abruptness of the displacement,
there is not the slightest indication of extra jointing,
shearing, or slickensiding. Instead the fold has occurred
as if the conglomerate were as plastic as wet clay. Hence
unless we hypothecate more intense folding than is observed
and a much thicker cover, which would induce greater
pressure, this type of fold can be explained only by the
supposition, that the conglomerates and other sediments
which have suffered in the same way, were soft and plastic
when the folding took place.

The Nanaimo series was subjected to strong orogenic
movement also, presumably during the post-Eocene deform-
ation, the deforming forces apparently having their origin
to the northeast, probably below the basin between Van-
couver island and the mainland. The series was deformed
into broad open folds, complicated by small closed folds
and reversed faults, the latter largely restricted to the west-
ern boundary of the basin. The axes of folding have a

325

general northwest-southeast strike, and the prevailing
dip is to the northeast. At the northern rim of the basin
in the vicinity of Departure bay, the general strike turns
from northeast to east, while the dip is to the southeast
and south. The largest fold, with the exception of the
major fold which outlines the basin, occurs on Gabriola
island. It is a syncline, which is divided into two parts
by a transverse anticlinal roll at the northern end of the
island.

A large portion of the region about Nanaimo is covered
by superficial deposits of various kinds, which are, however,
almost entirely referable to the Glacial period. This period
was characterized by two epochs of glacial occupation,
the Admiralty and the Vashon, separated by an inter-
glacial epoch, the Puyallup. Little or nothing remains of
the glacial till, which must have mantled a large part of
the area on the retreat of the earlier and larger Admiralty
glaciers. During the Puyallup inter-glacial epoch, a large
part of the lowland must have been covered by stratified
sands and clays, partly, if not entirely, of marine origin.
These inter-glacial deposits were largely eroded during
the Vashon glaciation, but now occur mantled by a
more or less persistant covering of Vashon drift, to the
northwest of Nanaimo and in the broad low area adjoining
the lower part of the Nanaimo river, to the south of
Nanaimo. On the retreat of the Vashon glaciers, large
delta deposits, composed chiefly of sand and gravel, were
built at the mouths of the large valleys, which extend
eastward from the Vancouver Island upland, and were at
that time presumably occupied by retreating valley glaciers.
The deposits have a maximum elevation of about 400 feet
(120 m.). The islands are not covered by these deposits
but merely by debris of the immediately underlying
rocks mixed with more or less glacial till and sometimes
overlying or closely associated with stratified sand and clay
of the inter-glacial deposits. It thus appears as if during
the deposition of the delta deposits the islands were still
covered by the piedmont Strait of Georgia glacier. It may
be that the deltas were deposited in lakes dammed by the
Strait of Georgia glacier, but, since it is positively known
by the occurrence of marine fossils in the vicinity (on
Texada island and near Vancouver) at elevations near
400 feet (120 m.) that a recent uplift of about 400 feet
35069— 4JB

326

(120 m.) has occurred, it is more probable that the deltas
were deposited in the salt water. As already mentioned,
since the uplift the delta deposits have been terraced and
retrograded.

The other superficial deposits consist of recent swamp,
valley, delta, and beach alluvium.

Geology of the Coal Deposits.

There are at present three productive coal seams in the
Nanaimo district lying in the following succession from the
bottom upwards: the Wellington; the Newcastle, some-
times called the lower Douglas; and the Douglas. The
lowest seam, the Wellington, occurs about 700 feet (210 m.)
above the base of the Nanaimo series, overlying 600 feet
(180 m.) of marine sandy shale, the Haslam formation. The
Newcastle and Douglas seams, are only from 25 to 100 feet
(8 to 30 m.) apart, and overlie the Wellington seam by
about 1,000 feet (300 m.), separated from it chiefly by a
thick bedded conglomerate, the Extension formation.
A fourth and small seam, called the little Wellington,
locally overlies the Wellington at a distance of 20 to 50
feet (6 to 15 m.). It has been mined in a small way.

The coals of the various seams are as a whole much
alike, and furnish a bituminous coal of fair grade. The
amount of fixed carbon in the best quality ranges from 45
to 60 per cent, and the ash from 5 to 10 per cent. The
following proximate and ultimate analyses were made by
F. G. Wait of the Department of Mines, from samples
collected by the writer.

327

ANALYSES.

1 I U A i friU>lC •

Analysis by fast coking.

Water

i-65

I • 16

1-54

43-25

40-47

33-30

Fixed carbon

45-52

50-04

5623

Ash

9 24

7-80

8-44

Sulphur

i 24

0 -53

o-49

IOO-

100-

Coke

_ O w ,

58 II

64-91

(firm,

ffirm,

Character of coke

<{ Gener-

\ coher-

< coher-

ic ent.

l ent.

[ ent.

Fuel ratio

I 07

1 23

1 65

Split volatile ratio

2 92

3-29

4 00

Ultimate.

72 -8o

75-53

74-46

Hydrogen

5-17

5-13

5-42

Nitrogen

o-88

119

i-37

10 67

9-82

Sulphur

1 24

o-53

o-49

Ash

9-24

7-80

8-44

100 •

loo-

IOO-

No. 1. Coal from the Wellington seam.

No. 2. Coal from the Wellington seam.

No. 3. Coal from the Douglas seam.
The most striking feature of the seams is their great
variability in thickness and quality. The thickness varies
from nothing to over 30 feet (10 m.), sometimes within
a lateral distance of less than 100 feet (30 m.). This
variation is caused by irregularities in either the roof or

328

floor, and occasionally in both. In quality the seams vary
from where they are entirely composed of clean, bright
coal, with about 5 per cent ash, to where they are entirely

composed of a dirty slickensided coal, locally called
"rash," with over 50 per cent ash. The following is a
proximate analysis of the rash from the Wellington seam.

Proximate Analysis by Fast Coking.

Water 1 59

Vol. combust 24-I5

Fixed carbon 19 29

Ash 54-97

Sulphur undet .

100 •

The Wellington seam rests on a firm sandstone floor,
which is fairly regular although a few sharp rolls do occur
in it. The roof, however, varies greatly in character from
sandy shale to conglomerate, with many irregularities,
especially in the sandy shale. The average thickness of the
seam is from 4 to 7 feet (1 to 2 m.), but it occasionally
pinches to virtually nothing, and then suddenly thickens
to 10 or 12 feet (3 or 4 m.). The floor may be nearly smooth,
but the roof in passing from the thin to the thick portion
of the seam rolls upward sharply and often irregularly.
Occasionally the roof is overturned forming in one instance
an overlap in the seam of at least 25 feet (8 m.). These
sharp rolls are locally called "faults." Invariably at
the thin places or "pinches" the coal is dirty and slicken-
sided, while in the thick places or "swells" it is clean,
black in colour with a sub-brilliant lustre, and broken only
by a few irregular joints. Rash is usually found near the
top and bottom of the swells and rarely in thin partings
near the centre. Even in the swells some bone is present
as small lenses seldom more than a quarter of an inch thick.
In some instances the coal is clean and unfractured against
the upturned roof, but more commonly it is somewhat
slickensided and even contorted. The roof at the rolls is
always contorted and slickensided.

The strike of the rolls corresponds with the strike of
the measures, that is, northwest to west, and the pinches
occur in the northeast and north side of the rolls with the
corresponding swells on the opposite side. Where the

330

seam is overlapped, the overlap is to the northeast or
north.

These features are illustrated by the accompanying
sections which are drawn to scale.

It appears from the evidence given above as if the
variation was due in large part to a folding which affected
the coal seams when the clean coal was in a fairly plastic
condition. This conclusion is especially well substantiated
in another part of the Wellington seam, where it is composed
of several sub-seams separated by dirty slickensided coal
or rash. During the deposition of the seam, conditions in
which fairly clean carbonaceous matter was deposited
must have alternated with those during which the car-
bonaceous matter was deposited with a large amount of
silt. When the seam was folded, the clean coal was
apparently forced away from the tight bends, where the
folding caused an increase in the vertical pressure, and
left the seam at these places composed almost entirely of
rash. The clean coal flowed to where there was a
corresponding relief of vertical pressure forming a swell
where the seam, except for the rash at the top and bottom,
consists chiefly of clean bright coal.

Besides the barren places or wants due to folding subse-
quent to the deposition of the seam, there are large wants
due solely to silting, for in some instances the silting must
have persisted throughout the period of coal formation.
Also large and persistent partings of shale occur between
the sub-seams.

Both types of variation occur in the Douglas seam. The
seam varies from nothing to 30 feet (10 m.) in thickness,
and averages about five feet (1-5 m.) although over large
areas the average thickness of the mineable coal is between
three and four feet (-9 and 1-2 m.j. The floor of the
Douglas seam is usually a rather weak sandy shale, and the
roof, although stronger, is very variable, ranging from a
sandy shale to a fine grained conglomerate, the principal
type being a shaly sandstone with sandstone layers and
lenses of fine grained conglomerate. Unlike the conditions
in the Wellington seam the pinches and swells are caused
chiefly by irregularities in the floor, the roof being fairly
smooth. At the pinches the seam is composed almost
entirely of rash, like that of the Wellington seam, although
as a rule it is harder. The coal occurring in the swell has a
compact texture, but rather dull lustre. It is irregu-

33'

larly broken into large blocks. Near the pinches some of
the coal is slickensided and contorted, but where these
features are shown the coal contains a higher percentage
of ash. The coal seam is displaced also by small faults,
although an actual break seldom occurs, the coal having
been forced along the plane or zone of dislocation. Rarely
the entire seam folds or wrinkles without any appreciable
variation in thickness.

The Newcastle seam is more regular than the Wellington
or Douglas seams, but is thinner, varying, as far as known,
from 20 to 45 inches (0-51 to 1-15 m.) where mined, and
contains more numerous and more regular partings. It is
also less extensive in area than the other two seams.

The coal has been the source of a flourishing industry
for over 50 years. The Wellington seam has been mined
at Wellington, Northfield, East Wellington, Harewood
Plains, and Extension, and is at present mined by the Van-
couver-Nanaimo Coal Mining Company at East Welling-
ton and by the Canadian Collieries (Dunsmuir) Company
near Extension. The Newcastle and Douglas seams,
which are usually worked together, have been mined
extensively in the vicinity of Nanaimo. The mines here
are operated by the Western Fuel Company. There has
also been a large production from the Douglas seam south
of Nanaimo, notably at Chase River, Southfield, and South
Wellington. In these localities the Newcastle seam,
although readily located, is of doubtful value. There is
only one mine producing at present in this district, the
South Wellington mine, operated by the Pacific Coast Coal
Mines. Both the Western Fuel Company and the Pacific
Coast Coal Mines are sinking new shafts along the lower
part of the Nanaimo river to open up the Douglas seam in
depth. The present coal production is over 1,000,000 tons
per year, and the importance of the Nanaimo district in
the coal industry may be more readily comprehended when
it is realized that it produces over one third of the endre
coal output of British Columbia.

PARTICULAR DESCRIPT ON.

From Nanaimo an excursion is made eastward across
Nanaimo harbour to Gabriola island. To the south are
the wharfs and coal bunkers of the Western Fuel Com-
pany.

332

The inner part of the harbour is underlain by Protection
sandstone, exposed to the north on Newcastle and Protec-
tion islands. On Protection island, Protection island
shaft, cutting the Douglas seam at 588 feet (179 m.) and
the Newcastle seam, at 652 feet (199 m.). Outer part of
harbour and Nanaimo valley to the south underlain by
Cedar District shales.

jack Point cuesta composed of DeCourcy sandstones,
which dip north of east at an angle of 25 degrees.

Galiano (Malaspina) Gallery.

Northumberland channel underlain by lower shale
horizon in the Northumberland formation.

West shore of Gabriola island, cuesta of Northumberland
sandstones, dipping north of east at an angle of 10 degrees.
Honeycomb weathering.

Decanso bay. Upper shale horizon of the Northumber-
land formations, underlying concretionary Gabriola sand-
stones Sandstone quarry.

Along shore of cuesta-like ridges of northeastward
dipping Gabriola sandstone. Angle of dip averages 15
degrees.

Locality 1 — Galiano (Malaspina) Gallery. Gabriola
sandstone, weathered by solution and wind.

Tinson point. Highest beds of Nanaimo series in the
vicinity of Nanaimo, nearly 5,000 feet (1,500m.) to Douglas
seams. Thin bedded Gabriola sandstones dipping north

333

at an angle of about 5 degrees. Small bays on either side
of point formed in a shaly horizon in Gabriola formation.

Lock bay. Northumberland shales dipping northwest
at an angle of about 15 degrees below Gabriola sandstone.
From Locality 1 across northward pitching syncline.
Transverse anticline crosses Gabriola syncline, which to the
south pitches southeast.

Locality 2 — Northumberland shales dipping southeast
at angle from 10 to 15 degrees, overlain by Gabriola sand-
stones, exposed in cliff, one quarter of a mile back from
shore. Shales with sandstone interbeds and sandstone
dykes.

Locality 3 — Snake island. Honeycomb and "gallery"
weathering of concretionary Gabriola sandstone dipping
eastward at an angle of 25 degrees.

Locality 4 — Islands and headland of Vancouver vol-
canics to north, evidently a headland of those rocks
that projected into the basin in which the Nanaimo series
was deposited. Unconformity, showing irregular surface
upon which Nanaimo series was deposited, and coarse
basal conglomerates (Benson formation) Departure Bay
calcarenites.

Locality 5 — From 4 across Departure bay, underlain
by Haslam, Extension, and Cranberry formations, which
have here a minimum thickness. To the west retrogarded
inter-glacial deposit. Abrupt downfold in conglo-
merate and coarse sandstone of the Cranberry formation.

Locality 6 — From 5 through Newcastle Island channel,
crossing Newcastle and Douglas seams at narrows. Brechin
mine of Western Fuel Company to the west, and old slopes
on the two seams to the east.

Quarry in Protection sandstone.

Along Newcastle Island channel to Nanaimo, near
contact of Newcastle and Protection formations.

East Wellington Mine — Wellington seam reached
through an inclined shaft, paralleling an old slope driven
on the little Wellington seam. Wellington seam in mine
fairly flat, with low dip from 5 to 10 degrees to the north-
east, but to the southwest the seam is faulted in a series of
steps, and outcrops at the surface to the southwest of the
surface plant with a steep dip to the northeast. Sharp
rolls or "faults", smooth sandstone floor, but irregular
sandy shale roof, in places overturned. Few small rolls
in sandstone floor. Faults in southern part of the mine.

334

Miles and
Kilometres.

ANNOTATED GUIDE.
(Nanaimo to Victoria).

o m. Nanaimo — Altitude 133 feet (40m.). From

o km. Nanaimo the railroad runs south, and for
about two miles follows closely the outcrop of
the Douglas seam. To the west may be seen one
of the recently abandoned slopes on the New-
castle seam. Farther west is the drift covered
lowland terminated by the steep slope of Mt.
Benson. Farther south near Chase river the
outcrop of the coal seams swings to the east,
and to the west are the bare back slopes of the
cuestas of Extension conglomerate, which dip
northeast toward the railroad.
3-3 m. Stark Crossing — Altitude 80 ft. (24 m.). At
5-3 km. Stark Crossing the railroad turns and runs east
for three quarters of a mile (1 km.), and then
again follows the outcrop of the Douglas seam
south by east for two and a half miles (4 km.).
Immediately to the west are the ruins of the old
Southfield mine, and a half a mile north of
South Wellington is one of the mines now
operated by the Pacific Coast Coal Mines, the
coal being brought to the surface through two
slopes on the seam.
5-3 m. South Wellington — Altitude 124 ft. (37 m.).
8 -5 km. At South Wellington is the abandoned Alex-
andria mine. To the east is the steep front
slope or cliff of the cuesta formed by the north-
eastward dipping Protection sandstones, and
to the west across the alluvial-filled,
submaturely glaciated valley, formed along
the outcrop of the Douglas and Newcastle
seams, and in which is situated Cran-
berry lake, is the back slope of a cuesta of
conglomerate of the Cranberry formation. To
the south the railroad, after crossing the railroad
of the Pacific Coast Coal Mines cuts through
the lower part of the white weathering Protec-
tion sandstone, and for over a mile runs in
places along the back slope of the Protection

335

Miles and sandstone cuesta. Tust before crossing the

Kilometres . J i r

Nanaimo river, a quarter of a mile north ot
Cassidy Siding, the railroad runs on to the
Nanaimo delta, built at the mouth of the upper
part of the Nanaimo River valley, during the
recession of the Vashon glaciers and terraced
by the recently revived river. Along its present
course the revived stream has cut a narrow
canyon, 80 feet (24 m.) deep, in the Protection
sandstone.

Cassidy Siding — Altitude 132 ft. (40 m.).
At Cassidy Siding the Protection sandstone
cuesta is seen to the west; to the east are the
low terraces of the Nanaimo delta, and still
farther east is the drift-filled, glaciated valley
formed in the Cedar district shales. To the
south the railroad crosses two branches of
Haslam creek, which here splits into two or three
channels while crossing one of the broad terraces
of the Nanaimo delta. South of Haslam creek
the railroad traverses the Nanaimo delta nearly
to Ladysmith.

10-9 m. Brenton — Altitude 95 ft. (30 m.). North
17-5 km. of Brenton a cuesta of Protection sandstone is
seen east of the track. To the southwest
beyond the terraced delta is the monadnock,
Mt. Hayes, elevation 1,450 feet (442 m.),
composed of Saanich granodiorite, and almost
entirely surrounded by the Haslam shales, and
hence presumably an island during the deposi-
tion of the lower members of the Nanaimo
series. From Brenton to Ladysmith the railroad
is parallel to the Extension railroad of the
Canadian Collieries Company, over which the
coal from the Extension mines is brought to
Ladysmith. To the north of Ladysmith, the
railroad cuts through the Protection sandstone,
which has here a nearly vertical dip, the base
on which the Nanaimo series rests occurring
only a mile to the west.
14-1 m. Ladysmith — Altitude 83 ft. (25 m.). To the
22 • 7 km. east is Ladysmith harbour, the drowned south-
ern portion of the glaciated valley developed
in the Cedar District shales. Beyond the

336

Kiiomeu-ts harbour is the Woodley range,a cuesta developed
on the northeastward dipping DeCourcey sand-
stones. At Ladysmith are the copper smelter
of the Tyee Copper Company and the wharfs
and washer of the Canadian Collieries Company.
South of Ladysmith the railroad closely follows
the coast, the coast lowland being but one
or two miles wide. To the east glimpses
are had of the drowned portion of the lowland.
To the west the Vancouver Island upland
steeply surmounts the lowland and almost
directly west of Chemainus, is Mt. Brenton
nearly 4,000 feet (1,200 m.) high.
21-3 m. Chemainus — Altitude 109 ft. (33 m.). South
33 -8 km. of Chemainus the lowland widens again to four
miles (6 -4 km.), and is drained by the Chem-
ainus river. It is largely drift covered and
wooded, and only a few outcrops are seen.
25-7 m. Westholme — Altitude 29 ft. (9 m.). South
41 -4 km. of Westholme the railroad enters a wide flat-
bottomed valley, the northern part of which
between Mt. Richards, 1,100 feet (340 m.)
high on the east and Mt. Sicker, 2,400 feet
(730 m.) on the west, is underlain by the
Nanaimo sediments. The Nanaimo sediments
almost surround the northern part of Mt.
Richards, having been deposited around it
while the mountain itself remained above sea-
level as an island or peninsula. Both Mt.
Richards and Mt. Sicker are composed of the
more or less mineralized schistose and intrusive
rocks of the Sicker series, a few outcrops of
which occur in the southern and narrowest
part of the valley. On Mt. Sicker occurred the
Tyee-Lenora lens of copper ore. The Lenora
railroad, extending from the mine to Crofton,
and now used as a lumber railroad, is crossed
a mile beyond Westholme, and at Tyee the
aerial tram of the Tyee Copper Company
comes down from Mt. Sicker.
28-1 m. Tyee — Altitude 129 ft. (39 m.). South of
45 -2 km. Tyee the railroad cuts through some deformed
black slaty shales. To the west on Mt.
Prevost, 2,643 feet (806 m.) high, these shales

337

KUomeS^s are unconf°rmably overlain by conglomerate,
apparently of the Nanaimo series, and still
farther west in the valley of Chemainus river
the shales grade northward into the Sicker
schists. They are presumably of Jurassic
or Triassic age, but are indistinguishable
from the Nanaimo shales which occur to the
east below the drift-covered flat extending from
the railroad to the shore.
29-9 m. Somenos — Altitude 108 ft. (33 m.). From
48-1 km. Somenos to south of Cowichan the railroad
crosses the large, maturely glaciated, subsequent
Cowichan valley, underlain by a closely folded
syncline of Nanaimo sediments, largely sand-
stones and shales. The valley is almost 50
miles (80 km.) long, and nearly divides the
southern part of Vancouver island. It is
glacially deepened, especially in its upper part,
where Cowichan lake lies. The Cowichan
river flows eastward from the lake, and for the
greater part of its course meanders in its flat
valley floor, some two to three miles wide,
between cut banks 10 to nearly 200 feet (3 to
60 m.) high, of stratified drift of inter-glacial
and post-glacial deposition, the river having
been revived by the recent uplift. At Somenos
is a brick plant using the inter-glacial clays,
which cover a large part of the lower portion
of the valley.

32-8 m. Duncan — Altitude 50 ft. (15 m.). Between
52 • 8 km. Somenos and Duncan, to the east of the railroad,
is Somenos lake, formed in one of the partly
drained hollows in the inter-glacial clays.
East from Duncan is Mt. Tzuhalem, which is
capped by the basal conglomerates of the
Nanaimo series resting unconformably on the
Sicker schists and porphyrites. The southern
slope is a fault line scarp, developed along the
fault which has thrown the Sicker series up
against the Nanaimo series to the south.
Farther to the east is Saltspring island, com-
posed largely of the rocks of the Sicker series.
The greater part of the island has an elevation
of 1,500 to 1,800 feet (450 to 540 m.) and is a

338

Kilometres remnant of the uplifted Tertiary peneplain.

Its southern slope is a fault line scarp, developed
along the eastward continuation of the fault
mentioned above.

34-4 m. Koksilah — Altitude 28 ft. (9 m.).

55 -4 km.

37- 0 m. Cowichan — Altitude 119 ft. (36 m.).
59-6 km.

38- 4 m. Hillbank — Altitude 150 ft. (46 m.). North
61 -8 km. of Cowichan is a quarry in the Xanaimo

sandstones, which are seen to be underlain by
shales. The last exposures of the Xanaimo
sandstones are seen to the north of Hillbank.
41 -3 m. Cobble Hill — Altitude 315 ft. (96 m.). To
66 -5 km. the west of Cobble Hill station is Cobble hill,
1,100 feet (355 m.) high, which with the excep-
tion of the northern slope underlain by Saanich
granodiorite, is composed of Vancouver meta-
volcanics, which form a belt 2 to 20 miles
(3 to 30 km.) wide extending to the west coast.
Numerous outcrops of the volcanics are seen
near the railroad to the south of Strathcona
and along the northern shore of Shawnigan lake,
although the volcanics are largely covered by
Vashon till. Just to the south of Strathcona
is a small lentil of Sutton limestone which is
intercalated in the Vancouver volcanics.
44-7 m. Koenig — Altitude 390 ft (119 m.).

71 -4 km.

Strathcona — Altitude 456 ft. (139 m.).

^ 25 Mile Post— Altitude 553 ft. (168 m.).
Shawnigan lake has been formed in the glacially
deepened portion of one of the mature, trans-
verse, north-south valleys, which dissect the
uplifted Tertiary peneplain. From Koenig the
railroad climbs rather rapidly up the steep
east slope of the Shawnigan Lake valley to
the pass east to the next transverse north-south
valley.

52-5 m. Malahat — Altitude 915 ft. (279 m.).
84-5 km.

55-5. m. 17 Mile Post — Altitude 733 ft. (223 m.).
89 -3' km. Beyond Strathcona and extending over the

339

Miios and summit at Malahat nearly to 17 Mile Post,

Kilometres. . , nri 11 ... .

is the Wark gabbro-dionte gneiss, numerous
outcrops of which are seen near the track and
on the slopes up to the level of the uplifted
Tertiary peneplain. Frequent apophyses of
the Colquitz quartz diorite gneiss are also
seen, in places so numerous as to form a breccia
of the two rocks. From the summit the rail-
road descends along the west slope of the
maturely glaciated, transverse, north-south val-
ley, which has been converted into a fiord,
called Saanich inlet. The southern or typical
fiord portion, along the side of which is the
railroad, is called Finlayson arm. To the south
of 17 Mile Post for nearly five miles (8 km.)
the road traverses an area of schistose volcanic
rocks, cut by two intrusive masses of the
Colquitz and Wark gneisses. The volcanics
are largely fragmental, of the composition of
dacites and andesites, and are interbedded with
sedimentary material. They are greatly de-
foimed and their dips are nearly vertical.
They have been mapped with the Vancouver
volcanics but are interbedded with and transi-
tional into the Leech River slates, which lie
to the south and which are probably Palaeozoic.
At 15 and 14 Mile Posts, canyons, called res-
pectively Arbutus and Niagara canyons, are
crossed on high bridges. They are the spillways
of hanging valleys. South of the schistose
volcanics are the Leech River slates, greatly
deformed, contorted and cut by quartz veins.
At the bend in the railroad west of Goldstream,
the Goldstream river is crossed. Here the Leech
River slates are covered by stratified coarse
gravels, which constitue the top-set beds of the
Colwood delta, built during the recession of
one of the Vashon glaciers which occupied Gold-
stream valley. To the north of the bridge the
Colwood gravels are seen resting on the blue
Vashon till. From the bridge to Goldstream
the railroad follows the profound overthrust
fault which separates the Palaeozoic Leech River
slates from the Eocene Metchosin basalts,
35069— 5B

340

Kilometres which lie to the south. The fault is marked by
a wide shear zone, with slickensided walls, some
of which may be seen in the cuts south of
the track.

6i-8m. Goldstream— Alt. 280 ft. (85 m.). From
99-5 km. Goldstream to Col wood, the railroad crosses the
terraced Colwood delta. To the north of the
track is Langford lake in one of the un-
drained hollows of the delta, possibly an
ice-blcck hole. To the east of Langford lake
is a gravel pit, where the coarse, horizontally
bedded top-set beds are well exposed, resting
on the finer, cross and steeply bedded fore-set
beds. The gravel is used for railroad ballast.
64-6 m. Colwood — Altitude 246 ft. (75 m.). To the
104-0 km. east of Colwood, the railroad descends from the
delta nearly to sea level, cutting through the
Vancouver volcanics, Sutton limestone lentils,
and small intrusive masses of Wark gabbro-
diorite gneiss and Colquitz quartz-diorite gneiss.
To the north of the track, a mile beyond
Colwood, is the plant of the Silica Brick Com-
pany. Limestone is quarried south of the
track, elevated over the track, and burned
in down draft kilns. The resulting lime is
hydrated and used in the manufacture of
sandstone brick, the sand being obtained north
of the track from the fore-set beds of the
Colwood delta.
66-8 m. Parsons Bridge — Altitude 99 ft. (30 m.).
107-5 km. From Parsons Bridge to Victoria, the railroad
traverses the southeast lowland of Vancouver
island. This portion of the lowland is largely
covered by May wood (inter-glacial) clays with
in places a thin mantle of Vashon drift, but
with numerous small monadnocks or ledges
of the crystalline rocks, Vancouver volcanics,
Sutton limestones, and Wark and Colquitz
gneisses. Three quarters of a mile east of
Parsons Bridge is a limestone lens that has
been quarried for flux by the Tyee Copper
Company.

68-8 m. Esquimalt — Altitude 35 ft. (11 m.). One
110-7 km. half a mile north of Esquimalt the railroad runs

34i

Kilometres along the west shore of Portage inlet, the
eastern of the two drowned glaciated valleys
which bound the Esquimalt peninsula. Cross-
ing the low "Portage" the railroad runs along
the western of the two drowned valleys, Esqui-
malt harbour. Between Esquimalt and Vic-
toria the railroad crosses the Esquimalt peninsu-
la. Two miles from Esquimalt on the south side
of the track is the British Columbia Pottery
Company's plant, where in the manufacture
of sewer pipe, flower pots, etc., the Maywood
clays are mixed with other more refractory
clays to bring up the plasticity of the refractory
clays. Crossing by a bridge the eastern drowned
valley, the outer portion of which is Victoria
harbour, the railroad enters the city of Victoria.

72-5 m. Victoria — Altitude 32 ft. (10 m.).
116-7 km.

REFERENCES.

1. Allan, J. A. Saltspring Island, and east coast of

Vancouver Island. Summary Rept .1909,
Geological Survey of Canada, pp. 98-102.

2. Arnold, Ralph. Geological Reconnaissance of the

Coast of the Olympic Peninsula, Wash-
ington. Bull. Geological Soc. America,
Vol. 17, 1906, pp. 451-468.

3. Bauermann, H. On the Geology of the Southeastern

part of Vancouver Island. Quart. Journ.
Geol. Soc, Vol. 16, 1859, pp. 198-202.

4. Clapp, Charles, H. Southern Vancouver Island,

Memoir No. 13, Geological Survey of
Canada, 1912.

5 Geology of the Nanaimo Sheet, Nanaimo

Coalfields, Vancouver Island. Summary
Rept. 191 1. Geological Survey of
Canada, pp. 91-105.

6. Clapp, C. H. and Shimer, H. W. The Sutton Jurassic

of the Vancouver Group, Vancouver

Island. Proc. Boston Soc. Nat. Hist.

Vol. 34, 191 1, pp. 425-438.

35069— 5|b

342

7. Dawson, G. M. The Superficial Geology of British
Columbia: Quart. Journ. Geol. Soc., Vol.
34, 1878, pp. 89-123, Vol. 37, 1881, pp.
272-285.

8 On the later Physiographical Geology of

the Rocky Mountain Region in Canada,
Trans. Royal Soc. of Canada, Vol. 8,
1890, sec. 4, pp. 3-74.

9. LeRoy, O. E. Preliminary Report on a portion of the

main coast of British Columbia and
adjacent islands. Geol. Survey of
Canada, Pub. No. 960, 1908.

10. Merriam, J. C. Note on two Tertiary faunas from

the rocks of the southern coast of
Vancouver Island. Bull. Univ. Cal.,
Dept. of Geol., Vol. 2, 1896, pp. 101-108.

11. Poole, Henry, S. The Nanaimo-Comox coal fields.

Summary Rept.. 1906, Geol. Survey of
Canada, pp. 55~59-

12. Richardson, James. Report on the coal fields of

Nanaimo,Comox, Cowichan, Burrard In-
let, and Sooke, B. C. Geol. Survey of
Canada, Rept. of Progress, 1876-77, pp.
160-192.

13. Sutton, W.J. The Geology and mining of Vanvouver

Island. Trans. Manchester Geol. and
Mg. Soc, Vol 28, 1904, pp. 307-314.

14. Weaver, C. E. A Preliminary Report on the

Tertiary Paleontology of Western Wash-
ington. Bull. No. 15, Washington Geol.
Survey, 191 2.

15. Whiteaves, J. F. On the fossils of the Cretaceous

rocks of Vancouver and adjacent Islands
in the strait of Georgia. Geol. Survey of
Canada, Mesozoic Fossils, Vol. 1, Part
II, 1879, PP- 93-/90.

16. On some additional fossils from the

Vancouver Cretaceous, with a revised
list of species therefrom. Geol. Survey of
Canada. Mesozoic Fossils, Vol. 1,
Part V, 1903, pp. 309-416.

17. Willis, Bailey, Tacoma Folio, No. 54, U. S. Geol.

Survey, 1899-

18 Drift phenomena in Puget Sound. Bull.

Geol. Soc. Am. Vol. IX, 1898, pp. 1 12-162.

343

FIRE CLAY DEPOSITS AT CLAYBURN, B. C.

Charles Camsell.

INTRODUCTION.

This excursion has been arranged to start from Van-
couver, B.C. going by electric car over the line of the B.C.
Electric railway to Clayburn, distant 46 miles (74 km.),
for the purpose of examining the brick works and fire clay
deposits situated at that point. These fire clay deposits
are the most important known in British Columbia, and the
fire brick manufactured at the works supply the market
for practically the whole province.

The route of the excursion lies eastward from Vancouver,
and, crossing Fraser river at New Westminster, continues
on the south side of that stream through the level country
which forms the delta of the Fraser.

The country embraced within the modern as well as the
ancient delta of Fraser river extends from Agassiz west-
ward to the coast, and runs southward into the State of
Washington. It is on the whole low and rolling, the eleva-
tions ranging from sea level to about 400 feet (122 m.)
above. Here and there, however, isolated hills, which
attain elevations as high as 1,000 feet (304-8 m.) above the
sea, rise above the general level of the plain. The northern
boundary of the delta is the Coast range of mountains,
whose slopes rise quickly from the delta plain to elevations
of 3,000 (914 m.) to 6,000 feet (1,828 m. ) above the sea.

The oldest exposed rocks of the region are the granitic
rocks of the Coast Range batholith, which border the delta
on the north. These rocks have been proved by borings
at Vancouver to underlie the Eocene rocks of the delta
itself.

Remnants of once more extensive Cretaceous beds occur
as hills rising above the general level of the delta in its
upper part near Agassiz, and around these the more recent
deposits were laid. Sumas mountain, on which the clay
deposits are situated is one of those.

344

Practically the whole of the delta is believed to be
floored by stratified rocks of Eocene age, which are referred
to in the literature as the Puget group. They consist of
only slightly disturbed conglomerates, sandstone, shales and
some lignite, laid down in an estuary as delta deposits of
the ancient Fraser river. They have an estimated thick-
ness in this region of about 3,000 feet (914 m.),and contain
a variety of plant remains from which their age has been
determined. This formation contains the fire clay deposits.

Overlying the Eocene beds are unconsolidated deposits,
of glacial and post-glacial origin, which were laid down
either sub-glacially or at the glacial front during the period
of ice recession. These lie at elevations as high as 400 feet
(122 m.) above sea level and consist of sands, gravel and
boulder clay. They form broad, flat-topped plateaus
which were at one time joined together and formed the
post-glacial delta of the river. Elevation of the land
relative to the sea, however, has taken place since, enabling
the river to cut into the older delta so that now only
detached remnants of it are to be found. This process of
deepening is related to the strong terracing of the upper
part of the Fraser valley. The stream is forming a modern
delta in the lower part of its course at the present time, and
this delta is gradually being pushed seaward into the Gulf
of Georgia.

Summary of Geological History of Fraser Delta.

The history of the delta as far as our present knowledge
allows us to read it may be summarized as follows:

1. Post-Lower Cretaceous revolution, followed by the
development of an estuary, probably by erosion, where the
delta of the Fraser river now is.

2. Deposition in the estuary of material derived by
erosion from the interior, and carried down by the ancient
Fraser river in Eocene times, forming the Eocene delta.

3. Gradual but continuous removal of much Eocene
material in succeeding Tertiary times.

4. Glacial period.

5. Formation of Glacial delta by deposition of glacial
material during the closing stages of the Glacial period.

6. Post-Glacial uplift resulting in the cutting down and
removal of much of the glacial delta deposits.

7. Formation of modern delta at the mouth of the
stream.

345

ANNOTATED GUIDE.

Miles and
Kilometres.

o m. Vancouver — Leaving Vancouver on the

o km. British Columbia Electric railway to Chilliwack
the line runs east through the suburb of Grand-
view, and then turns southeastward across the
peninsula separating Burrard inlet from Fraser
river, passing, on the way, through the suburban
settlements of Collingwood, Central Park and
other places to New Westminster. From Van-
couver the line gradually mounts the ridge to
the southeast of Vancouver and at Central
Park reaches an altitude of 450 feet (137 m.)
above sea level. Although this ridge is under-
Collingwood — lain by rocks of Eocene age
Central Park — to a depth of several hundred
Burnaby — feet no exposures other than
those of the Recent and Glacial deposits are
visible from the car. These represent the
remains of delta deposits laid down in the clos-
ing stages of the Glacial period. The summit
of the ridge is flat and was at one time heavily
forested.

Beyond Central Park, occasional glimpses
can be obtained of Fraser river on the right
through openings in the trees, and shortly after
passing Burnaby the descent to the river is
begun.

12 m. New Westminster — The town of New West-

19-3 km. minster is one of the older places on the mainland
of British Columbia, having been established
in 1859. It is situated on Fraser river at tide
water, and has deep water connection with the
sea. It is built on the slope of a hill facing the
south, having the modern delta of Fraser river
directly in front and the snow covered volcanic
cone of Mt. Baker, 11,000 feet (3,352 m.) in
elevation, in the distance to the southeast.
At New Westminster the Fraser river is crossed
by a steel bridge which affords accommodation
for railway as well as vehicular traffic.

346

Miles and
Kilometres.

12 m.
19 km.
16-5 m.
26-5 km
22 m.
35'4 km.

25-5 m.
41 km.
29 m.
46-6 km,
32 m.

51- 5 km.
32-5 m.

52- 3 km.

35 m.
56-3 km.
37 m.
59-5 km.
42 m.
66 km.

44 m-
70-8 km.

South Westminster — Exposures of fine

grained Eocene sand-
Kennedy — stone showing cross

bedding are seen in the
Sullivan — railway cuts at South

Westminster. Beyond
this the line gradually ascends the slope of
Strawberry hill, until at Kennedy it reaches an
altitude of about 300 feet (91 m.), above the
sea.

Strawberry hill, like Mount Lehman farther
east, is a flat topped plateau covered by uncon-
solidated sands and gravels representing delta
deposits laid down at the close of the Glacial
period. They are erosion remnants of the old
delta which have not been removed by the
post-Glacial deepening of Fraser river.
Cloverdale — Descending the eastern slope

of Strawberry hill, the line crosses
Langley — Serpentine river and enters a low

level country which extends along
Milner — the route of the excursion as far

as Jardine. This level country
Jardine — is only a few feet above sea level

and is part of the delta built up
by Fraser river in modern times when that
stream emptied into Mud bay.

Cloverdale, Langley and other places on this
part of the route are the centres of much good
agricultural country.

Sperling — At Jardine the line begins to

rise again to the top of another
Coghlan — of those low plateaus built of
sands, gravel and glacial ma-
Bradner — terial deposited in the delta of
the Glacial period. This pla-
Mt. Lehman — teau is known as Mount Leh-
man and has an elevation of
about 300 feet (91 m.) above the sea. It
is heavily wooded and traversed by a number
of sharp deep valleys. Sections of the deposits
of which it is built can be seen in a number of
places along the line of travel.

347

Miles and
Kilometres.

46-5 m. Gifford — Descending the eastern slope
74 -8 km. of Mount Lehman near Gifford,

49 m. Clayburn — the line is only a short distance
78-8 km. from Fraser river, which can be

seen on the left. Here again is low flat open
country only about 20 feet (6 m.) above sea level.
The railway runs for about five miles (8 km.)
through this country to Clayburn station
which is about one mile distant from the brick
works of the Clayburn Brick Company.

From the brick works a narrow gauge railway
runs up the valley of Kelly creek into Sumas
mountain for a distance of about 3! miles
(5-6 km. ), to the fire clay deposits. The
railway is used for carrying the clay from the
mines to the brick works and is operated solely
for the convenience of the Clayburn Brick
Company.

GEOLOGY OF THE REGION ABOUT CLAYBURN.

GENERAL DESCRIPTION.

The village of Clayburn, populated almost entirely by
people employed in the mines and brick works, is situated
on the western edge of Sumas mountain, about a mile
from the station. Sumas mountain itself is a heavily
wooded hill rising through the flat lying delta country
to an altitude of about 1,000 feet (305 m.) above sea
level. The central part of the mountain is made up of
massive quartz porphyries which are believed to be of
Lower Cretaceous age, and around this has been deposited
a series of beds of Eocene age consisting of conglomerate,
sandstone, shale and thin seams of coal. The Eocene
beds rest unconformably on the quartz porpyhry floor,
and have a gentle dip ranging from 5 to 15 degrees to the
southwest. Outcrops of these rocks are rare, and on the
lower slopes of the mountain they are covered by Pleisto-
cene sands and clays.

The Eocene deposits contain the beds of fire clay which
are said to be the most important on the Pacific Coast of
Canada.

348

PARTICULAR DESCRIPTION.

About 1,000 feet (305 m.) up Kelly creek from the
brick works is situated a bank of clay from which material
is obtained for manufacture into common brick. The
section in the bank shows a bed of sand separating two
beds of clay, over which is about 15 feet of river gravels.
The beds are all of glacial or post-glacial origin and not
firmly consolidated, so that they can be worked by a
steam shovel.

Two miles (3.2 km.) beyond these clay deposits is the
Thornton mine, the first mine at which the Eocene shales
are worked. These beds outcrop on either side of the
creek and consist of shales overlaid by conglomerate and
underlaid by sandstone. The beds are of Eocene age and
dip about 6 degrees to the southwest. The shale is
separable into two beds which are described by Dr. H.
Ries (4, p. 390) as "a lower grey shale of smooth plastic
character, and an upper purplish one which is harder and
grittier. The former is buff-burning, and on the south side
of the track is at least 6 feet (1.8 m.) thick, while the
upper or grey burning shale is 4 (1.2 m.) to 6 (1.8 m.)
feet thick." A test of the lower shale by Dr. Ries showed
it to be of good plasticity, burning to a good buff pressed
brick.

A mile beyond the Thornton mine and on the opposite
slope of the mountain is what is known as the fire clay
mine. This was formerly worked as a coal mine and
contains a seam of coal up to 3 feet (.9 m.) in thickness.
The section at this mine as measured by Dr. Ries is as
follows:

Sandstone

Upper fire clay

Coal with flint clay partings

Lower fire clay

Ferruginous clay

China clay

8 ft. — 2.4 m.

6 in. to 1 ft. — .15 to. 3m.

7 ft. — 2 . 1 m.
4 ft. — 1 .2 m.

10 to 15 ft. — 3 to 4.5m.

Only the portion between the coal seam and the china
clay is at present being mined, a selected sample of which
fused Cone 32. The china clay is a fine grained whitish
clay fusing at Cone 22. It is not being mined.

349

INDUSTRIAL NOTES.

The shales of the Thornton and fire clay mines are
mined underground by pillar and stall methods, and an
output of about ioo tons per day is maintained.

The capacity of the brick works is about 80,000 bricks
per day, and the product of the kilns includes common,
pressed and fire brick, drain tile and sewer pipe, and various
other fire clay products.

BIBLIOGRAPHY.

1. Bowman, Amos: Geol. Surv. of Canada. Vol. III.
p. 66-A.

2. Daly, R. A.: Geol. Surv. of Canada. Vol. XIV.
p. 42.

3. LeRoy, O. E.: Geol. Surv. of Canada. Report on a
Portion of the Coast of B. C. and adjacent Islands, 1908.

4. Ries, Heinrich: Canadian Mining Institute. Vol.
XIV. Clay and Shale Deposits of the Western Provinces
of Canada.

VICTORIA, BRITISH COLUMBIA, TO CALGARY,

ALBERTA.

The east bound portion of C 1 Excursion follows as far
as Calgary, the same route as that taken in the westward
journey, the guide to which is given on pages 105 to 274
of Guide Book No. 8, Part II.

CALGARY TO WINNIPEG.

Via Canadian Northern Railway.

A. Maclean.

INTRODUCTION.

At Calgary the excursion leaves the main line of the
Canadian Pacific railway, and runs as far as Winnipeg

350

over the lines of the Canadian Northern railway, following
a route considerably north of that traversed in the west-
bound journey.

This route lies towards the northern fringe of the prairie
portion of the Great Plains area, through a region whose
main geologic and physiographic features are similar to
those obtaining in the southern part of the same region,
a description of which is given on pages 77 to 99 Guide
Book No. 8.

The points of interest to be seen on this portion of the
excursion include: Dinosaurian bone beds at Munson,
Alberta; Foraminiferal Cretaceous limestone and the
beaches of glacial Lake Agassiz at Pine River, and the
fossiliferous Devonian on Lake Winnipegosis, where the
fauna is of a distinctly European type.

ANNOTATED GUIDE
(Calgary to Munson.)

Calgary — Altitude 3425 ft. (1,044 m-)-
From Calgary the route of the excursion lies
northeastward over an open rolling prairie
country to Munson which is situated on a
tributary of Red Deer river.

Munson — Altitude 2,600 ft. (780 m.). Here
a short excursion is made to points along Red
Deer river, where beds of the Edmonton form-
ation, containing Dinosaurian remains, are
exposed.

THE EDMONTON FORMATION ON RED DEER
RIVER NEAR MUNSON, ALTA.

The distance from Munson to the Red Deer along the
shortest route is about six and a half miles (10.5 km.)
This route is directly west along the road running in an east
and west direction through the town.

Owing to the proximity to Fox coulee and the Red Deer
valley, the road crosses several tributary coulees on its
way to the river. After crossing the first of these just
outside the town, one reaches a summit from which the
land slopes very gently to the banks of the Red Deer.

35i

From this summit may be seen several of the prominent
physiographic features of the region.

To the east, about 18 miles (29 km.) beyond Munson,
rises the Hand Hills ridge — the most marked of all the hills
to be seen from here. To the southwest of this on the other
side of Red Deer valley, are the Wintering Hills, while in
front — to the north and west — are the Three Hills, and
still nearer Sarcee Butte. To the immediate west is the
valley of the Red Deer river, and to the south and west
across this valley is the rough and broken country about
the Knee Hill creek, which stream flows into the Red Deer
river, at a point about directly southwest of Munson.

Near Munson the subsoil is very heavy, giving the
heavy waxy "gumbo" soil of the western plains, but on the
last facet of the upper slope before reaching the edge of
the cut banks, the soil becomes lighter and contains more
sand. Both types of soil, however, have given excellent
results during the period they have been cultivated.

At a point four miles (6-4 km.) to the west of Munson,
one may continue for two and a half miles (4 km.) farther
west and come directly to the edge of the cut banks, or
turn to the south and so get a road along a fairly good
grade to the river flats either at the Wigmore ferry or at
the Wigmore ford — opposite the mouth of the Three Hill
creek. To reach this latter place the road turns again to
the west at a point one and a half miles (2-4 km.) south
of the last road intersection, and finally follows a private
trail down to the river flats, and then along these in front
of the Edmonton exposures.

In passing down to the river flats, and in driving along
them, there are several excellent examples of the different
stages of denudation and erosion. On either side of the
river valley several coulees and ravines have cut their
sharp "V" valleys back into the table land above. Just
across the river the Three Hill creek, having cut its channel
down to the present base level of its mouth, has subsequent-
ly widened its valley to have a fairly extensive flat at the
bottom. On the nearer (northeast) side of the river, among
the Bad Land features, are many cases where the valleys
in heading back from the river, have encroached on each
other and have cut off one or more buttes from the table
land behind. In other cases these have been worn from
the flat-topped buttes to sharp ridges or conical hills,
which finally pass to low rounded hummocks in the last

352

stages of denudation possible with the present river level.

As seen from below, the cut banks of the river and coulees
and the sides of the buttes show the typical exposures of
the Edmonton series. From the level of the river flats
below to the grassy slope above, the light and dark coloured
banks or beds are so marked and so characteristic that
even from a distance of some miles one has no difficulty
in detecting them and iecognizing them as belonging in
all probability to this formation. On close examination
it is seen that the light coloured bands are greenish or
yellowish gray in colour, and consist of sandstone, shale or
clay, with the clay predominating.

The dark coloured bands are red or black in colour, the
red bands being often similar in composition to the gray,
with the exception that they have a much higher ferric
iron content. In some cases this iron has been concentrated
in several bands of ironstone concretions. These bands
are in general from four to six inches (10 to 15 cm.) in
thickness, and are distributed at various levels in different
places. On the weathered bank they project from the
slope for a few inches, until the nodules of which they are
composed are undermined, and of their own weight fall to
the bottom of the bank.

The black bands are either of a dark shale, or mark the
outcroppings of different seams of coal which may be as
many as six in number, although this number is not con-
stant, since these beds are not always continuous for great
distances. The smallest of these coal seams at this place
is about six inches (15 cm.) in thickness, and the largest
about three feet (im.).

As exposed at the surface the coal is of poor quality,
being lignitic in character. It crumbles and disintegrates
rapidly on exposure to the changes of the atmosphere,
but when freshly mined or when exposed under water,
the quality is much better and has a wide local use. In
many instances it is simply quarried or mined out of the
nearest exposure by the farmers themselves, but in addition
to this there are several mines which supply the towns and
such of the farmers who care to buy at the pit mouth.

It is within one of these seams that the greatest amount
of fossil wood is preserved. Stumps, tree trunks, and
large slabs of "wood" may be found lying along the river
flats near the place where they have weathered out of the
coal seam.

353

Many of the remains are more or less silicified, and in
some cases are opalized. In most cases, the structure is
excellently preserved, the fossil wood being so like the
modern that in many cases it is easily mistaken for a piece
of recently weathered wood.

The vertebrate remains occur at a higher level, some 60
or 70 feet (18 or 21 m.) below the top of the bank. The
bed containing them, varies from a yellow clay or shale to
a fairly compact gray sandstone, and the state of preser-
vation differs with the material of the bed in which it is
found. Some excellently preserved specimens are found
in association with the concretionary iron beds, but in these
cases, it is almost impossible to separate the iron from the
bone.

Owing to the fact that most of the exposures are on the
steep face of the cut bank, it is sometimes difficult to find
the complete set of bones in place. As the bank is eroded,
some of the bones become undermined and roll to the bottom
of the slope, where they lie until completely broken up by
exposure. By tracing these fragments up the bank, some
may be found projecting a few inches from the surface.
To extract them from this bed means that a large amount
of overburden has to be removed, or that the bones should
be taken out by " mining".

Most of the specimens found here are reptilian, of the
order Dinosaurs [6 and 7], although farther down the
river there are reported remains of fishes and small mam-
mals. None of these have as yet been found in this region.

The exact position of this fossil-bearing bed is often
difficult to determine, owing to the tendency of the bank to
break and slide to the lower levels. On these slips, erosion
is often more effective than on the undisturbed levels above,
so that, in some cases, the bone-bearing beds have been
exposed by the butte weathering down to its level. In
such cases, the task of collecting is comparatively easy.

The slipping of the banks mentioned befoie is in this
formation even more prevalent than in other regions where
clay forms the greater part of the subsoil. The tendency
to slip is increased by the presence of a varying amount of
"bentonite" disseminated through the whole formation,
and sometimes aggregated in beds of considerable thickness.
This material when moist, is very waxy or soapy, and when
given sufficient amount of water has a tendency to become
very gelatinous and to expand excessively. The presence of

354

bentonite in the subsoil is probably in part the cause of the
waxy nature of the "gumbo" soil, and is also responsible
for a great many of the engineering problems, where
difficulty is experienced in holding a road bed on the side
of a cut, or even in maintaining the grade over a level
prairie underlain by it.

Throughout this part of this formation there is a distinct
lack of continuity in the beds. In some exposures there
may be shown a regular succession of beds of clay with
no sandstone apparent, while a short distance away
distinct hard beds of consolidated sandstone are found
interbedded with shale and clay. In some cases, the clay
passes imperceptibly into the sandstone, and in other cases
gradually pinches out into a thin lens, while above it the
sandstone comes in again in the same manner.

On this account it is difficult to give a section which is
applicable without modification throughout the whole
region, but the following section as worked out by J. B.
Tyrrell may be considered as fairly characteristic of the
Edmonton formation in this region. [3].

ft. in.

3-0 m. Light coloured boulder clay, including many

Laurentian boulders and pebbles — at least io

6- 0 m. Whitish, clayey sandstone 20

3- 6 m. Grey, carbonaceous shale 12

•7 m. Coal (burnt out) 2 4

4- 5 m. Whitish, clayey sandstone 15

•7 m. Coal (brown lignite) 2 3

7- 5 m. Light grey sandy shale with 6" band of iron-

stone near top 25

1-8 m. Yellow, sandy shale 6

0- 6 m. Shale, mixed with coal 2

18 -o m. Grey, readily weathering sandstone, with ir-
regular masses of ironstone and reptilian
bones 60

1- 5 m. Lighter grey sandstone 5

0-3 m. Sandstone and ironstone 1

7-5 m. Light grey, rather hard, sandy shale, with

irregular bands of ironstone 25

•15 m. Nodules of flinty ironstone, with impressions

of plants o 6

3-0 m. Light sandy shale 10 o

0- 75 m. Hard ferruginous sandstone, containing

obscure plant impressions 2 6

1- 8 m. Light grey sandy shale 6 o

•3 m. Rather hard lamellar sandstone 1 o

33 o m. Light grey shaly sandstone, containing especi-
ally in the lower portion, more or less
irregular bands of ironstone nodules no o

94 -68 metres.

315 7

C3.

Geological Survey, Canada.

Red Deer Volley in the vicinity of Munson and Drumhcller

Miles

I O / Z 3

Kilometres

I O I Z 3 ■ 4 5

355

ANNOTATED GUIDE.

MUNSON TO DAUPHIN VIA SASKATOON.

Oometres ^he route traversed between Munson, Alberta,
from ■ [ and Dauphin, Manitoba, is over hilly and
saskatoon. roumg prairie underlain by Cretaceous rocks.

The first section between Munson and Saska-
toon is mostly prairie, while the country to the
east of Saskatoon as far as Grandview is fairly
well wooded. Just west of Dauphin the railway
cuts through the first prairie escarpment between
the Riding and Duck mountains.

The country is underlain by the Edmonton
series [3 and 4j as far east as Richdale, then
succeeded in descending order by the Fort
Pierre shales which extend east to Grandview.
From this point nearly to Dauphin, the country
is underlain by the Niobrara shales and marls
succeeded at Dauphin by the Dakota series.

Munson — Altitude 2,600 ft. (780 m.). Just
west of the station a cutting in a coulee shows
about six feet (1 -8 m.) of stratified sand which
is not consolidated to a consistent stone.
Overlying it is a hard band of sandstone exceed-
ingly rich in fossils (Ostrea). This band is
about eight inches (20 cm.) in thickness, and
probably owes its consistency to the presence of
cementing material from the shells which form
the greater proportion of the bed.

From mile posts 166-167 to the river, both
sides are denuded to show typical exposures of
the Edmonton formation, and the railroad
enters the lower river flats at mile post 170-5.

Munson Junction — Altitude 2,604 ft.
(781 m.). The Hand hills to the east rise about
1,000 feet (303 m.) above the general level of the
prairie and form the most marked physio-
graphic feature of this region. They have
received their name from the resemblance which
their outline bears to an outstretched hand,
four or five ridges or "fingers" to the south
radiating from a broader elevation, "the palm",
to the north. The Indian name Michichi
35069— 6b

356

KUomeTres ispatinati referred to this resemblance and the
idea has been retained in the English appelation
— the Hand hills.

The lowest exposures of these hills show rock
of the Edmonton series. Above this may be
seen in some places, the brownish sandstone of
the Paskapoo series, while the summit of the
hills is covered with beds of Miocene age.
These beds are about 270 feet (81 m.) in thick-
ness, and this exposure is the only one of any
extent in this region.
245 m. Richdale — Altitude 2,587 ft. (776 m.). To the
374 km. west of Richdale the country is comparatively
flat and the soil heavy and rather impervious, so
much so that sloughs are common, and deposits
of alkali are more prevalent than farther east,
where the land is comparatively dry and the
soil not excessively heavy. The crossing of
Berry creek near Richdale marks the boun-
dary between the Edmonton series to the west
and the underlying Fort Pierre shales to the
east.

Youngstown — Altitude 2,434 ft- (730 m.).
East of Youngstown toward Benton, the hills
form a ridge extending in a northeasterly
direction. The surface generally varies from
irregular to gently rolling with an almost
complete absence of tree and scrub.
106 m. Brock — Through Brock and Darcy the

170-5 km. ridges tend northeasterly. The cuttings show
deposits of gravel and glacial till heavily
charged with boulders.
78 m. Ridpath — West of Ridpath the railway

125-5 km. skirts the Bad hills, and the country in conse-
quence is somewhat rougher. Eastwards to
Delisle the country is typical flat prairie,
becoming more rolling on approaching Delisle
and passing into a zone of hilly country to the
west of Vanscoy.
505 m. Saskatoon — Altitude 1,655 ft. (500 m.).
812-7 km. Saskatoon lies in one of the great wheat growing
from Winnipeg, centres of Western Canada, and is situated on
the bottom lands of glacial Lake Saskatchewan,
the eastern border of which lies about 30 miles

357

Kiiomeu-es (48 km-) to the east of the city* Neither the
area nor the shore line of the lake has as yet been
worked out in any detail.
278-7 m. Kamsack — Kamsack marks the crossing of
448-4 km. the broad valley of the Assiniboine. The
divide between the Assiniboine basin and the
river flowing into Lake Dauphin is reached at
Shortdale. The wind gap at this point is a
result of the piracy of the Valley river.
207-4 m. Grand view — Grandview marks the upper
333-7 km. limits of glacial Lake Agassiz. From there to
Gilbert Plains the railway crosses the delta
deposits formed during the highest stage of the
lake.

1 89 • 4 m . Ashville — Ash ville is situated on a well marked
304-8 km. beach of glacial Lake Agassiz. Delta deposits
of a later date than the above extend from
Gilbert Plains to Dauphin. The cuts along
Valley river show exposures of the Niobrara
formation.

177-8 m. Dauphin — Altitude 957 ft. (287 m.).
286- 1 km.

ANNOTATED GUIDE.

DAUPHIN TO ETHELBERT AND PINE RIVER.

177-8 m. Dauphin — Altitude 957 ft. (287 m.). Dau-

286-1 km. phin is a junction point on the line of the
Canadian Northern railway from which subsi-
diary excursions run northward to Pine River
and Lake Winnipegosis. The object of the
excursion to Pine River is to examine fora-
meniferal Cretaceous limestone, and at the same
time to view beaches of glacial Lake Agassiz
which are here excellently preserved. At Lake
Winnipegosis, Devonian rocks are exposed
which in places contain Stringocephalus burtoni,
a fossil common in the Devonian of Eurpoe,
but only found in America in this locality and in
the valley of Mackenzie river. ,

1 96 m. Sif ton Junction — Altitude 959 ft. (287 • 7 m.) .

313-6 km. From Sifton Junction the road takes a north-
westerly course as far as Ethelbert, at which
35069— 6|b

358

Kiiometn4s P^ce it turns to the north-northwest, and
continues this direction through Gasland, Pine
River, Sclater and Cowan. Beyond Cowan
the road turns to the west, following approxim-
ately the contour line in front of Duck mountain.
This line is here deflected toward the west as
a result of the break in the escarpment face
caused by the valley of Swan river.
210 m. Ethelbert — Altitude 1,126 ft. (338 m.). Be-

336 km. tween Sifton Junction and Ethelbert, the road
gradually ascends the old bed of Lake Agassiz
toward the western shore line. In this distance
it doubtless crosses a number of the later shore
lines of the lake formed during its recession,
but in this region they are obscure and not
easily recognized.

The first distinctly marked beach along this
line is reached at Ethelbert, just after the road
crosses Fork river and enters the town. The
elevation here is 1,126 feet (337 m.), so that
this shore line is 167 feet (50 m.) above the
lake bottom at Sifton. At this same elevation
this beach continues south for about 25 miles
(40 km.), to a point about west of Dauphin.
It stands out as a distinctly marked ridge,
and forms the location for a government colo-
nization road. At Ethelbert, this road turns
to the west for a mile, and then follows another
of the benches which will be mentioned later,
while this beach is occupied by the railroad
between Ethelbert and Pine River.

At Ethelbert an opportunity is afforded to
observe the relation of the beach to the surround-
ing country. The railway is here located on the
summit of the beach, while the main street of
the village is on its eastern flank. An exami-
nation of the ditches and excavations along
this shore line shows distinctly the sands and
gravels of a shore deposit.

About one mile (i-6 km), to the north of
the town a road running toward the east shows
very good sections of other lower beaches.
The first is about 300 yards, (270 m.), to the
east of the track, and the second about a mile

359

and a half (2-4 km.) east of the railroad.
The first is not very distinct, but the second is
fairly well marked, and seems to be continued
toward the north. In both these instances,
the beaches are distinguished rather by their
content than by any marked ridge or terrace
effect, although this also is to be noticed by
careful examination and observation.

On returning to Ethelbert and crossing that
beach toward the west, there is evident a
feature which is often to be noticed along
these lines, that is, that the ground immediately
behind and to the west of the beach is lower than
the summit of the beach itself. As the general
drainage of the district is toward the east,
this results in a stretch of marshy land to the
west or upper side of the old beach. In other
cases the streams from the west, being deflected
by this barrier, flow along parallel to the beach
until they reach a gap which has been cut
through the old shore line. In this manner
the ground to the west is cut still lower, and the
ridge appearance of the beach is accentuated.

One of these streams, a branch of Fork river,
is to be noticed as soon as the Ethelbert ridge is
crossed. Beyond the valley of this stream, the
land rises slowly toward the west for about a mile
(i-6 km.), till another and larger beach is met.
This beach rises to a height of about 40 feet
(12 m.) above the summit of railroad at Ethel-
bert. Throughout its length this beach is
larger and better marked than the one to the
south along which the railroad runs. Like
that one also, the ridge — locally termed " the big
ridge " — drops off sharply on the western side to
the valley cf another branch of Fork river.
On the eastern flank the government coloniza-
tion road previously mentioned, continues
northward.

One mile (i-6 km.) farther to the west is
another beach. Like those to the east of
Ethelbert, however, this beach is also marked
by a gravel bed of apparent shore origin rather
than by a distinct change in elevation. The

360

Miles and beach corresponding to this is better marked

Kilometres. T,. . 1 p . , . ,

at Pine River, and may be observed there.
219 m. Garland — Altitude 1,127 ft. (358 m.). From

350-4 km. Ethelbert to Garland, the railroad as has been
before mentioned, follows the lower of the
two most distinct beaches. This beach with
practically no grading, forms the road bed with
the exception of a few places, where streams
have broken through the ridge, and so have
necessitated filling and bridging.

At Garland, an irregular trail runs to the
east toward Winnipegosis. This road crosses
three of the old beaches in four miles (6-4 km.)
but as the country is bush covered the relative
elevations of the ridges are concealed. The
prevalence of Banksian pine and the light
dry soil underfoot readily call attention to them,
however, and subsequent examination reveals
them as well marked beaches.
229 m. Pine River — Altitude 1,146 ft. (344 m.). At
366-4 km. Pine River a better opportunity is afforded
of leaving the lower ridge, and again observing
'the big ridge' to the west, which is distant
from the railroad about three quarters of a
mile (1-2 km.) A rather poor trail leads
across the wet heavy soil commonly found
between the ridges, but when the ridge is
reached, a good trail runs along it to the north.
In following this trail for a mile or two in this
direction, the shore line features are especially
well shown.

At about 1-3 miles (2-1 km.) north of Pine
River station, both ridges are cut through by
North Pine river. South of this, the lower
ridge had been gradually approaching 'the big
ridge, ' and after this interruption, has apparently
lost its identity in the side of the more western
one, which continues north of the river more
marked than before.

After crossing the river, the main trail con-
tinues to follow the ridge, skirting the bank
of the river for some distance. About one
mile from the river crossing, this trail branches,
the main branch continuing along the ridge

36i

and a minor trail following up the course of
the river. On this trail, at about two miles
(3-2 km.) from the place where the main trail
crosses the river, are to be seen a series of three
beaches. These succeed each other at short
intervals, are very well marked, and as in
many other instances are covered with Banksian
pine.

Along the North Pine river are several
exposures of Cretaceous rocks. A short dis-
tance above the point where the main trail
crosses it, the river cuts into "the big ridge".
At the base of this cutting, about 12 feet
(3 . 6 m.) of shale is to be seen. This shale is for
the most part of a dark gray colour and thin
bedded, and weathers to thin flakes which
rapidly disintegrate to mud. About seven
feet (2 . 1 m.) above the water level is a thin bed
of yellowish white clay, soft in texture, and
having a peculiar astringent taste.

A short distance up the river and on the same
side — the north — is another similar exposure.
Both of these are probably of the Benton series.
[4].

About three quarters of a mile (1.2 km.)
farther up the river are two cliffs on the opposite
or south shore of the river giving very good
exposures of the Niobrara shales [4] and lime-
stones. The shales are of a lighter colour than
those of the Benton below, and the limestone
might better be described as marl or at least
calcareous shale. It is very rich in foraminifera,
Globigerina especially being present in large
numbers. In addition to these, other and larger
fossils are to be found in considerable quantity.
Of these, a species of Inoceramus and a large
species of Ostrea are particularly abundant.
[5, p. 102].

362

ANNOTATED GUIDE.

DAUPHIN TO WINNIPEGOSIS.

Miles and
Kilometres
from Winnipeg.

177-8 m. Dauphin — Altitude 957 ft. (287 m.).
286- 1 km.

195-5111 Sifton Junction — Altitude 959 ft. (287 m.).

312 -8 km. Sifton Junction almost overlies the contact of
the Cretaceous and Devonian, and from this
point to Winnipegosis the road is over the latter
rock although as before no exposures are to be
seen along the line of railway.

The railway here passes through a flat, wooded
country wThich is now being opened to settlers.
Through the clearings made by them occasional
glimpses may be had of the escarpment to the
wTest.

200-5 m. Fishing River — On this branch railway two
320-8 km. stations are passed — one at Fishing River and
the other at Fork River. At these places two
streams of the same names
207-6 m. Fork River — respectively cross the railway
332 • 1 km. Altitude 872 ft. and empty into Mossy river,
(261 m.) which stream drains Lake Dau-

phin and empties into Lake
Winnipegosis about one half mile (-8 km.)
north of Winnipegosis station.

From Sifton north to Winnipegosis, the coun-
try is mostly settled by Ruthenians who still
retain in the architecture of their churches and
houses and in their methods of farming many of
the ideas which they brought with them across
the sea. In addition to these are a number of
Icelanders settled in and
218 m. Winnipegosis — around the town, and during
340-8 km. Altitude 839 ft. the summer a few Indians
(251 m.) usually move down from the

Pine Creek reserve and pitch
their camps near the village.

A lumber mill is in operation near the mouth
of Mossy river, but the principal industry of the
town is fishing. Some years ago this was prose-
cuted throughout the year, but latteily it has

3^3

been restricted to the winter season, when the
fish must be caught from under the ice. By
means of horse and dog teams communication
is maintained between the fishing stations and
the village in winter, while in summer, the lake
is navigated by gasoline launches, steam tugs
and sailboats.

THE DEVONIAN OF SNAKE ISLAND AND SOUTH
SHORE OF LAKE WINNIPEGOSIS.

The southern end of Lake Winnipegosis is underlain by
the Manitoban formation of the Upper Devonian. The
grey limestones of this formation are best seen at Snake
island about four miles (6-4 km. ) east of the town of
Winnipegosis and the mouth of the Mossy river. On the
south end of the island is located the Government fish
hatchery. This and the buildings connected with it are
the only structures erected there.

The island is about a mile (i-6 km.) in length. It is
very irregular in shape, the two ends being about one half
mile (o-8 km.) in width, while the isthmus which joins them
is often but 50 feet (15 m.) in width. This irregular shape
is probably due to the manner in which the rock outcrops
at different places on the island and to the direction of the
prevailing winds of the lake.

The long axis of the island lies in a direction about north-
east and southwest. The outcrops all occur on the north-
western face of this axis. Three of these — two on the north
end and one on the south — stand from 15 to 20 feet (4-5 to
6 m.) above the lake. In the lee of these elevations,
sheltered from the prevailing west and north winds, the
island has been gradually extended toward the south and
east by continued marshy growths. At the middle of the
island, where the rock barely comes above the surface of
the lake, this protecting influence is lacking. Here only
such marsh has been formed as has been able to creep in
with the aid of the shelter given by the larger trees which
have grown on the expansions at the ends of the islands.

The shore on the northwestern face shows no such
marshy growths. The strong winds blowing from this
direction tend to prevent marshy vegetation gaining a
foothold on this side, while the heavy ice shoves of the

364

spring season serve to effectually scour out the shore and
so maintain a clean gravel beach along the front. The
effect of these ice shoves may be seen in the movement of
some of the large boulders which lie thickly scattered along
the shore, and in the long parallel ridges of non-assorted
gravel which build up the beach some feet above the marshy
ground beyond and behind it. These ridges may be
further worked over by the waves which serve sometimes
to intensify and sometimes to lessen the effect produced by
the ice shove.

As already indicated the rock outcrops are five in number:
two at the north end ; two on the isthmus ; and one on the
southern expansion.

In the three exposures which stand high enough to show
the dip, there is a marked inclination of the beds, varying
from 50 to 150 in direction from S. 850 E. to S. 450 W. The
dip in each case, however, seems to be quite local, and does
not serve to bring any new beds to the surface, for in all
five outcroppings the rock seems quite similar, and it is
probable that there is no bed exposed on the island that is
not represented in the higher of the two cliffs at the north
end.

The first exposure at this end forms the northwest corner
of the island, and extends for about 200 feet (60 m.) along
the northeast shore, and about 300 feet (91 m.) along the
the northwest shore. The dip, from 4 to 5 degrees is fairly
constant in a direction about S. 8o° E. to S. 700 E. This
causes the beds to dip down to the shore and under the
water on the northeastern side, and brings them out in a
cliff on the northwestern. From the summit of this cliff,
the beds gradually break away toward the southwest till
they are lost under the drift and gravel of the beach.

At its highest point the cliff stands 12 or 13 feet (3-6 m.)
above the water. It consists of three fairly well marked
divisions. The lower four feet (1-2 m.) is a fine
grained, fairly brittle limestone, light in colour and bearing
a few fossils. Above this is a coarse, dark bed of limestone,
very fossiliferous and from 12 inches to 15 inches (30 cm to
38 cm.) thick. A weathered section of this shows innu-
merable sections of brachiopod and other shells. The
upper surface of this bed displays fragments of shells in all
conditions of mechanical disintegration. This comminu-
tion together with wave marks shown on one of the blocks

365

from this level, would indicate that this bed at least was
formed at a depth within the limits of wave action.

In some places the succeeding beds are separated from
this by a thin layer of shale o • 4 inches ( 1 • cm.) thick. These
upper beds are similar to the lower five feet, but are darker,
not quite so fine grained, and are perhaps more fossiliferous.

They are seen to better advantage in the next exposure
to the southwest, where a cliff about 20 feet (6 m.) above
lake level shows a total thickness of 12 or 13 feet (3 • 6 or 4 m)
above the fifteen inch (38 cm.) fossiliferous bed previously
mentioned. In a bed at the summit of the cliff, 11 feet
(3-3 m.) above this middle layer, are shown some of the
star shaped sponge spicules.

Astreospongia hamiltonensis occurs abundantly in a single
bed of the limestone.

Other fossils which have been collected here include the
following: — Cyathophyllum lermiculare var. praecursor,
Alveolites lallorum, A try pa reticularis, A try pa spinosa,
Cyrtina hamiltonensis, Paracyclas elliptica, Raphistoma
tyrrellii, Bellerophon pelops, Euomphalus subtrigonalis ,
Omphalocirrus manitobensis, Hyolithes alatus, Gomphoceras
manitobensis , Cyrtoceras occidentale.

The cliff mentioned appears, as seen from the lake, to be
a section across an anticline. On closer examination, it
appears to be a section through a dome some distance
beyond the centre. The apparent dips along the face,
which at either end bring the beds up from the shore level,
are but the components in this plane of the angles of dip
which would radiate from the centre of the dome.

Below this cliff a great many of the blocks are from the
middle highly fossiliferous bed, which appears more
resistant than the other beds. On one of these blocks are
shown distinct curved wave marks, three crests and three
hollows, the distance from crest to crest being about 18
inches (45 cm.) and the depth of the hollow below the crest
about four inches (10 cm.) .

Farther to the south flat lying exposures are shown, one
at each end of the isthmus. They appear to be horizontal
and probably represent beds near the middle of the cliff
before mentioned.

On the southern end of the island, just at the hatchery
dock, is the last rock outcrop. This dips comparatively
sharply towards the southwest, the angle of inclination
varying from 15 degrees to 30 degrees. In all a total

366

thickness of about 12 feet (3-6 m.) is exposed. These
beds seem to be similar to those shown in the upper half
of the 16 foot (4-8 m.) cliff on the north end of the island.

Other outcrops of the rocks here described are to be seen
on the south shore of Lake Winnipegosis adjacent to the
island. As may be noticed on the map one of these is
directly west, and the others directly south of the south end
of the island.

None of these exposures exhibit any features not shown
at that place, with the exception perhaps of those imme-
diately south which may contain more fish remains than
the outcrops on Snake island. These remains are probably
of Dinichthys canadensis mentioned by Tyrrell in his report
on the island. [4 p. 163.]

The vicinity of Winnipegosis and Snake island is par-
ticularly interesting from the standpoint of the develop-
ment of the knowledge of Western geology for "It was
here that Prof. H.Y. Hind [1.] in 1858 made the collection
of fossils which first determined the existence of Devonian
in Manitoba." [4 p. 163]. In the same year a report was
made on the occurrence of rock on the island by A. W.
Wells [2.]. In the summer of 1889, the island was visited
and reported on by Tyrrell [4.], from whose report the
references just cited have been taken.

THE DEVONIAN OF DAWSON BAY, LAKE
WINNIPEGOSIS. (a)

Dawson bay is a large pocket-like expansion extending
west and south from the northern end of Lake Winni-
pegosis. This bay is excavated wholly in Devonian rocks
and the numerous exposures on its islands and shores and
along Red Deer river show the whole of the Devonian section
so far as it is known. This makes Dawson bay the most
favourable region in which to study the Devonian section
of Manitoba.

A spur leaving the main line of the Canadian Northern at
Mafeking reaches the bay at the mouth of Steep Rock
river. From this point the localities to be mentioned will
be reached by gasoline launches.

a This excursion is contingent on the completion of the branch railway from
afeking to the mouth of Steep Rock river.

367

The basal beds of the Devonian, which rest upon
Silurian limestones northeast of the entrance to Dawson
bay, are not known to be exposed about the north end of
Lake Winnipegosis. The Devonian section of this region
includes two formations, the lower is a dolomitic limestone,
estimated to be 200 feet (60 m.) thick, called the Winni-
pegosan of middle Devonian age. The upper formation
is chiefly a non-magnesian limestone, but it includes some
shale, and has a thickness of about 210 feet (64 m.). The
younger Devonian formation has been called the Mani-
toban. The lower Devonian appears to be absent from
this region. The sharp dips of 5 to 20 degrees seen at
some localities have only local significance. The general
dip of the rocks of this region is westerly and amounts to
probably not more than 40 feet (12 m.) per mile.

It follows, therefore, that the outcrops showing only
the lower formation of the Devonian lie mainly on the
eastern side of the bay.

A typical exposure of the Winnipegosan dolomite is
shown in the cliff at Whiteaves point 10 miles (16 km.)
east of the mouth of Steep Rock river. Whiteaves point
is a cliff of white compact dolomite with a maximum height
of 31 feet (9-4 m.) above the water, and extends a mile
along the shore. Beautifully preserved fossils occur in
abundance in this dolomite. Among the common and
characteristic forms are Stringocephalus burtoni and
Gyroceras canadense. The first named species, although
a familiar middle Devonian fossil in Europe, is known in
America only in the Devonian of Manitoba and Mackenzie
River valley. It is nearly everywhere a common fossil in
the Winnipegosan dolomite, but does not range upward
into the Manitoban formation. Another excellent exposure
of the Stringocephalus dolomite occurs at Salt point four
miles (6 -4 km.) west of Whiteaves point. About 30 feet
(9 m.) of white dolomite, weathering yellowish, are exposed
in the cliff here. The fauna includes a considerable number
of species, among which may be noted Sphaerospongia
terssellata, Columnaria disjuncta, A try pa reticularis,
Gypidula comis, Stringocephalus burtoni, Kefersteinia
subovata, and Paracyclas antiqua.

The Manitoban or upper Devonian formation is exposed
in several cliffs and points to the north of the mouth of
Steep Rock river within a few miles. One of the best
sections is exposed at Point Wilkins. Point Wilkins, which

368

is four miles (6-4 km.) north of Steep Rock river, rises 80
feet (24 m.) above the lake. The cliffs here expose the
following beds of the Manitoban formation: —

b. Light grey, fine grained, thin-bedded limestone,
some beds breaking with conchoidal fracture, 45 ft. (13 • 7 m.)

a. Light ash grey, argillaceous limestone 35 ft. (10 -6 m.)

The species which are most abundant in the lower beds
(b) are A try pa reticularis and Paracyclas elliptica. The
upper beds contain a very sparse fauna, in which Athyris
vitata is one of the most abundant species. Stringocephalus
burtoni and many of the other fossils of the Winnipegosan
dolomite are unknown in this upper formation.

An interesting feature of the Point Wilkins section is the
brecciated beds which appear very near the southern end
of the cliff. Here, where the cliff has a height of only about
25 feet (7-6 m.), the horizontal and undisturbed limestones
pass abruptly into a belt of limestone which has been
broken into large angular blocks; these have been more or
less completely recemented together. Some of the inter-
spaces are rilled with a light grey micaceous sandstone.
There are no Devonian beds in any part of the section
which resemble this sandstone filling. It probably repre-
sents material which sifted into the interstices of the
breccia during the deposition of the Dakota formation of
the Cretaceous, which further westward overlies the
Devonian limestone.

Immediately south of the Point Wilkins cliffs, and a few
rods from the brecciated limestone an old forest-covered
beach of comparatively recent date rises about 15 feet
(4-5 m.) above the surface of the lake. Another and much
older beach or bar 6 to 8 feet (1 -8 to 2-4 m.) high extends
across the top of the cliff 100 to 200 yards (91 to 182 m.) back
of its face. This beach stands about 85 feet (26 m.) above
the level of the lake. The present high stage of the lake is
indicated by the line of dead birches now standing on the
edge of the lake along the foot of the Point Wilkins cliff
on the northeast side.

Numerous salt springs issue from the Devonian limestone
at various points along the streams entering the west side
of Dawson bay. North of the mouth of Bell river, two
and three quarter miles (4 -4 km.), a small brook enters
the lake which is estimated to discharge into the lake
37I tons of salt every 24 hours [4.]. The salt beds thus
indicated in the Devonian are known only through the
saline springs.

369

ANNOTATED GUIDE.
(Dauphin to Winnipeg.)

Miles and
Kilometres
from Winnipeg

177-8 m. Dauphin — Altitude 957 ft. (287m.). Dau-
286 km. phin lies about 177 miles (286 km.) northwest
of Winnipeg, and is situated just to the east
of the first prairie escarpment which marks
the boundary between the fiat floored valley
of glacial Lake Agassiz and the second prairie
steppe. This escarpment, in its southern ex-
tension to the southwest of Ochre, is known as
Riding mountains, and continues northwards
under the name of Duck and Porcupine moun-
tains, the three groups being separated by the
cross valleys of Valley and Swan rivers. The
escarpment has been formed by aqueous erosion
of the almost horizontal Cretaceous rocks
overlying the Palaeozoic which forms the major
portion of the bed rock floor of Lake Agassiz.

Between Dauphin and Winnipeg the railway
crosses the following series. From Dauphin
to Ochre the road is underlain by the Dakota
series, succeeded by Devonian limestone which
extends to Makinak. Between Makinak and
Laurier the railway again crosses the Dakota
and the approximate contact between the
Benton and Dakota is about six miles (9-6 km.)
140 m. McCreary — north of McCreary. Be-

225 km. tween McCreary and

92-6 m. Gladstone — Gladstone the country

149 km. is underlain by the Ben-

55- 5 m. Portage la Prairie — ton shales, succeeded at
89 km. the latter point by the

Dakota sandstone, the lowest series of the
Cretaceous, which extends as far as Beaver.
From Beaver to Portage la Prairie the under-
lying rock is Devonian. East of Oakville
toward White Plains the country is underlain
by the Silurian, no outcrops, however, occurring
adjacent to the railway.

From Headingly to Winnipeg, the underlying
rock is Ordovician limestone and shales,
o m. Winnipeg — Altitude 761 ft. (232 m.).

o km.

3?o

BIBLIOGRAPHY.

1. Hind, H. Y Report on Assiniboine and Saskat-

chewan Exploring Expedition, To-
ronto, 1859.

2. Wells, AAV Appendix No. 36 to 17th. Vol. of

the Journals of the Legislative
Assembly of the Province of Canada.

3. Tyrrell, J. B Report on a Part of Northern Al-

berta, Geol. Surv. Can., Vol. II,
Part E, 1886.

4. Tyrrell, J. B Report on Northwestern Manitoba,

Geol. Surv. Can., Vol. V, Part E,
1890-91.

5. Whiteaves, J. F... .Contributions to Canadian Paleon-

tology, Geol. Surv. Can. Part IV,
p. 102, 1892.

6. Lambe, L. M Contributions to Canadian Paleon-

tology, Vol. Ill, Quarto, Part 3,
1904, page 76 of list of Bui.

7. Osborn, H. F. and

Lambe, L. M. . . .Contribution to Canadian Paleon-
tology, Vol. Ill, Quarto, part 2.

WINNIPEG TO PORT ARTHUR.

A. L. Parsons.
ANNOTATED GUIDE.
(Winnipeg to Kenora).

Winnipeg — Altitude 757 ft. (230-7 m.).
The level, treeless prairie at Winnipeg, repre-
senting the former bed of glacial Lake Agassiz,
extends eastward along the Canadian Pacific
railway to Darwin. In this distance, however
it gradually changes to a somewhat rolling,
heavily forested country and, eventually, at
Darwin, gives place to the hummocky, glaciated

Miles and
Kilometres.

o m.
o km.

37i

Kilometres rock surface of the Pre-Cambrian shield. The
underlying Ordovician limestone is hidded
except at Tyndall and Garson, where quarries
may be seen at some distance from the railway.
69-5 m. Darwin — Altitude 972 ft. (296-3 m.). From
101 -8 km. Darwin to Summit, a total distance of 340
miles (547 km.), the route crosses a region under-
lain by alternating stretches of Keewatin schists
and Laurentian granite-gneisses that present
no points of particular interest. The solid
rocks are covered more heavily than usual
with boulder clay and stratified clays, and
consequently the topographic relief is even
less than in most parts of the Pre-Cambrian
shield. Rock-bound lakes are very numerous.
132-7 m. Kenora — Altitude 1,088 ft. (331 -6 m.). The
213-5 km. Keewatin-Laurentian contact lies not far to
the north of the railway in the vicinity of
Keewatin and Kenora. In consequence of
this, the Keewatin schists have been contact-
metamorphosed into highly crystalline horn-
blende schists and gneisses.

A fine view of Lake of the Woods is obtained
just as Kenora is entered. This town, the
largest between Winnipeg and Fort William,
is the business centre for mining, lumbering
and milling industries in the Lake of the Woods
district.

PRE-CAMBRIAN GEOLOGY IN THE NORTHERN
PART OF LAKE OF THE WOODS.

General Geology of the Region.

The northern part of the Lake of the Woods is
characterized by rocky shores, numerous islands and
a rugged topography, though the elevation of the
highest hills above the level of the lake is seldom more
than 150 feet (45 m.). Though most of the islands
and the main shore are covered with a dense forest
growth, principally of second growth spruce, jack pine
(P. banksiana), and birch, there is as a rule not a great
depth of soil overlying the rock, which can be seen almost
35069— 7B

372

continuously along the shores. The rugged relief of this
northern part of the lake is in decided contrast to the region
south of Grande Presqu'ile. where many sandy beaches
and dunes and high rocky shores are uncommon.

According to Dr. A. C. Lawson (1), to whom our geo-
logical knowledge of this district is chiefly due, the Pre-
Cambrian rocks are separable into four principal groups:
Keewatin; Laurentian: a series of granites younger than
the Laurentian ; and Keweenawan.

KEEWATIN.

The oldest of these formations, the Keewatin, is divided
for purposes of mapping into four divisions which appear
to be lithologically distinct, but at times grade so
imperceptibly from one to another that it is well nigh
impossible to draw hard and fast boundaries. These are : —
(a) Hydromicaceous schists and nacreous schists, with
some associated chloritic schists and micaceous schists,
and including areas of altered quartz porphyry.

(b) Clay slate, mica schist and quartzite, with some fine
grained gneiss.

(d) Hornblende schist and altered trap, with some
chlorite schists of volcanic origin.

In addition to the above, some bands of carbonaceous
schists and ferruginous dolomite and possibly some
serpentine are included in the Keewatin.

Of the four principal divisions the last two are definitely
referred by Dr. Lawson to an irruptive origin; the first
is said to have been laid down by sedimentation, though
probably originally volcanic, and the second is assumed
to be of a sedimentary origin.

Hydromica Schists, Nacreous Schists, etc. — Dr.
Lawson seems to consider that the members of this sub-
group are largely sedimentary, though originally volcanic
(volcanic ash beds). He recognizes quartz porphyry as
the original rock from which part of the series was derived.
The writer's study would indicate that they resulted
largely from the alteration of a diorite or andesite similar
to the more acidic portions of the ellipsoidal trap. In the
development of these schists, the rock passes through a
stage which has been called agglomerate, though this term

373

is made to include two classes of rock, friction breccias or
autoclastic rocks and volcanic breccias formed where a
dark lava has intruded the older lavas. The friction
breccia is the common intermediate stage in the develop-
ment of the sericite schists. These schists with the breccia
agglomerate are shown on the unnamed island west of
Queer island, also upon Slate island in the vicinity of a
Keweenawan dyke.

A marked feature of these schists is the prevalence of
ferro-dolomite or ankerite, which in some cases forms vein-
like masses as much as 20 feet (6 m.) in width. As a rule
this material is not pure, but contains streaks of sericite
or chlorite and some quartz. Its weathered surface is
ochre yellow and of striking appearance. Good examples
of ferro-dolomite can be seen on a small island east of
Pipestone point and north of Square island, on the mainland
east of Square island, and on an island east of Whiskey
island. Another conspicuous band of this material is
shown on the west side of Middle island.

Clay Slates, etc. — This subdivision consists principally
of highly altered hornblende and biotite schists which may
or may not contain garnet. In some instances true slate
has been found, but this is only in small quantity. In
regard to making a distinct division of the Keewatin to
include these rocks there is considerable diversity of
opinion. It may be said, however, that they have been
found principally in close proximity to Laurentian masses
or to the later (?) granites and there seems to be no objec-
tion to considering them merely as highly altered phases
of the ordinary Keewatin traps. In numerous instances
this rock contains large veins of pyrrhotite which have been
prospected for gold, but as a rule these deposits have been
found to be of no economic value.

In certain places on West Hawk lake these highly altered
rocks (7, p. 202) seem to be of sedimentary origin, but so
far as partial analyses of rock from Lake of the Woods show
(7, p. 179), the rocks of this subdivision found there are
probably of igneous origin.

This highly altered rock outcrops near Keewatin and
Norman. It underlies the town of Kenora and continues
thence in a northeasterly direction for about six miles
(9-6 km.).

Agglomerate. — Under this title are grouped fragmental
rocks of extremely varied texture and origin. The more
35069— 7Jb

374

common type of agglomerate appears to be merely a brec-
ciated Keewatin trap or andesite which grades into sericite
schist. This rock is usually light coloured, and is well
developed near the Keweenawan dyke on the unnamed
island west of Queer island. Through a cartographic error
this outcrop was shown on the older maps as clay slate.

Agglomerate; Kenora, Ont.

The other principal type of agglomerate is also a breccia,
but in this case the brecciation is probably caused by a
flow of dark lava which has broken off fragments of solid
rock and cemented them together. It is possible, however,
that this type is due to the falling of volcanic bombs and
ash into molten lava, though the gradation from the
ellipsoidal trap to agglomerate on the east side of Ash
bay would strengthen the former suggestion. This type of
agglomerate is well exposed near the old saw-mill in
Kenora.

Altered Traps, Hornblende Schists and Chlorite
Schists. — These rocks, which are by far the most widely
distributed of the Keewatin rocks in this region, are prob-
ably all of the same origin. In general it may be said that

375

these ancient traps are diorites (or diabases in some
instances) with an ellipsoidal or pillow structure. In
places that have been badly weathered, this structure is
sometimes obscured, but careful search will usually reveal
it even when the trap has been largely altered to chlorite
schist. The ellipses usually consist of a light coloured

classed as diorite. In the interstices between the ellipses
is a filling of ferro-dolomite or ankerite with some quartz and
frequently a considerable quantity of epidote. Rocks of
this character are particularly well shown at Devil's Gap
and on the west side of Big Stone bay from the Keewatin
mine to Eagle passage. In these places the typical
ellipsoidal structure is well developed. In other places the
squeezing of these ellipses in the alteration of the rock to
chlorite schist and in certain instances to sericite schist
is beautifully shown.

At the contact of the Keewatin with the Laurentian
there is found usually, if not always, a hornblendic rock

376

which is considerably breccia ted and evidently resulted by
recrystallization of the ancient traps. This type of material
is to be seen near the Sultana mine and on the west side of
Bottle bay, where domes of granite show nearly every
possible phase of this rock from the slightly altered trap
with pillow structure to the brecciated hornblendic rock

Brecciated contact, Keewatin and granite. Sultana mine.

included in domes of granite. Sometimes even the granite
domes are free from it except near their margins. To the
west of the small indentation on the north side of Andrew
bay, several of these granite domes, with the brecciated
hornblendic rock grading into the ancient traps, are to be
found. These domes have the typical "roches moutonnees"
structure and have evidently been denuded by glaciation,
but it is of interest to note that the resultant form has been
determined not by the ice but by the original intrusion of the
granite. Examples of this structure are extremely common
in other parts of Lake of the Woods particularly along the
shore of Grande Presqu'ile. These however are beyond
the limit of the excursion.

377

LAURENTIAN.

The Laurentian formation in the Lake of the Woods
region is represented by large areas of granite and gneiss.
This group is almost entirely lacking on the shores of the
northern part of the lake, though there are several granite
outcrops which may belong to it but have been referred to
a later period by Dr. Lawson. If, however, the trap dykes,
which are elsewhere described, are to be assigned to the
Keweenawan it will probably be necessary to refer part
of this granite, to which a later origin has been assigned,
to the Laurentian. This would apply to the outcrop on
Micrometer island, where the trap cuts the granite, and it
would probably apply to all the granite in the northern
part of the lake.

Typical Laurentian granites and gneisses are to be seen
from the train on the Canadian Pacific railway at Margach
(formerly Rossland) and west of Dailington bay near
Keewatin. In the present excursion no outcrop of un-
questioned Laurentian rock is visited, though probably
the granite at the Sultana mine is to be so classed. There
is an extensive development of rocks of this age north of
Kenora and in the region to the east of Route bay. The
most interesting area, however, from many points of view
is the Grande Presqu'ile, which is essentially a series of
domes of granite and gneiss with margins of highly altered
Keewatin trap, and may be compared with the granite
outcrops on the north side of Andrew bay and on the west
side of Bottle bay. In the Andrew bay outcrops the
granite protrudes through the surrounding traps in large
dome-like masses which, near the contact with the trap,
contain numerous fragments of re-crystallized trap, while
at Bottle bay some of the domes are overlain by arched
masses of the older trap, and others are like those to the
north of Andrew bay.

The character of those granite masses can probably be
best studied near the Sultana and Ophir mines. There
the texture varies from that of a coarse granite porphyry
to a granitic and even microgranitic texture. Near the
contact with Keewatin traps there are places where it is
difficult to distinguish the two rocks, as both are fine
grained and have possibly undergone an interchange of
material which seems to furnish a gradation between them.
This however, is not the usual case ; ordinarily the contact

378

is a brecciated one of no great width, the Laurentian is
granitoid and the adjoining Keewatin is a dark finely
crystalline hornblende schist or diorite.

LATER GRANITE.

Several of the above mentioned outcrops of granite,
supposed to be later than the Lauientian, have been
minutely described by Dr. Lawson, but the distinctive
characters by which they may be distinguished from the
Laurentian granites are apparently lacking in the exposures
to be visited.

KE WEEN A WAN.

A remarkable series of dykes crosses Lake of the Woods
and Shoal lake in a general northwest and southeast
direction. The continuation of some of these in Rainy
Lake region gives a length of about 100 miles (161 km.)
to some of the better developed dykes.

These dykes are essentially a coarse grained quartz
diabase with a porphyritic border. In the original des-
cription (2), garnet is mentioned as one of the prominent
minerals in the central portion, but this has not been found
in the material secured by the writer from outcrops of Lake
of the Woods. The other minerals observed as well as
the characteristic texture of the rock, agree with the des-
cription given by Dr. Lawson. In the northern part of
Lake of the Woods four of these dykes are known, while
in Welcome channel a fifth dyke, that has been altered to
serpentine, may possibly upon further study be correlated
with these.

The adjacent Keewatin rocks usually show marked
metamorphism for 20 to 30 feet (6 to 9 m.) away from the
dykes. This is more evident in sericite schists con-
taining ferro-dolomite, though is is also to be observed in
the chloritic schists. As a result of this metamorphism
the schists are crumpled, and epidote, magnetite and
hematite, which are readily noticed in the field, are formed.

The most accessible of these dykes is that which was
mapped on Thompson island and Whitefish bay. It has
been traced almost without interruption from Darlington
bay to the east side of Whitefish bay, and is apparently
continuous with a dyke on Crow lake. In places, as on

379

Allie island, the rock is much decomposed, giving a chloritic
or serpentinous mass in which native copper is found,
though this material has not been observed in the unaltered
rock.

Gold Mines of the District.

For about thirty years the region around Lake of the
Woods has attracted more or less attention on account of
discoveries of gold, and mining has been carried on with
varying degrees of success. Several very rich pockets have
been found, and gold to the amount of about two million
dollars has been recovered from the mines on this lake and
Shoal lake. At the present time there is little activity,
though the Cameron Island mine and the Canadian Home-
stake mine are developing on low grade ore.

The best known mines of this region are: the Mikado,
with a reported production of about half a million dollars;
The Regina or Black Eagle mine, with a production about
equal to that of the Mikado; and the Sultana mine, with
a production estimated between seven hundred thousand
and a million dollars. At the time of writing none of these
mines are being worked. In all three the veins fill fissures
which cut across the contact between granite and Keewatin
traps. The vein material is largely quartz, but with this
is a large quantity of ferro-dolomite which weathers to a
rusty brown on exposure to the atmosphere.

Itinerary.

The following itinerary has been selected to show
characteristic examples of the different formations des-
scribed by Dr. Lawson. Two minor formations, the
carbonaceous schists and the serpentine, are omitted, as
they are too far distant to be reached in a trip of one
day.

At the long pier near the residence of Captain H. A. C.
Machin is a remarkably fine outcrop of agglomerate
which shows large fragments of acidic rock in a paste of
darker, more basic rock. It has been supposed by some
that this is a conglomerate of water-worn pebbles and
boulders, but, although there is no apparent means of
determining the origin of this rock at this place, its deriva-
tion is well shown in the neighbourhood of Ash bay as
probably being from a volcanic breccia.

38o

Leaving the agglomerate the route lies through the
beautiful islanded part of Lake of the Woods which extends
for about 10 miles (16 km.) from Kenora. On the main-
land is a large brick school devoted to the education of
Indians, while the cottages of the summer residents are to
be seen on nearly every island. A narrow channel, known

The Devil's Gap.

as Devil's Gap, separates Rat Portage bay from the main
part of the lake, and in passing through it the peculiar
landmark which gives this channel its name is seen on the
left. The rock along the shores is the characteristic ellip-
soidal trap of the Keewatin, though the ellipses are not so
marked as some that are to be seen later. Although
showing a well preserved elliptical structure, all these rocks
when broken exhibit a schistose structure. On a small
island on the left of the channel is an outcrop of felsite
which is probably connected with the Laurentian.

On the mainland to the left is an exposure of trap which
has been referred to a later age by Dr. Lawson. This
trap is so distinct in appearance from the other later traps
and so similar to the recrystallized traps in contact with

38i

the Laurentian granite that it seems doubtful whether it
is not merely a highly metamorphosed Keewatin trap.
Strength is give to this supposition by the proximity to
the felsite just mentioned and to the granite to be seen a
little later on the mainland. The dome-like outline of
the outcrop is also suggestive of the granite domes to be
seen in Bottle bay.

A good view of the Manitou stretch to the right gives
an idea of the large, open portions of the lake, while to the
left the protected waters of Matheson bay are to be seen.
All the mainland between Devil's Gap and the Sultana
mine is an Indian reserve, and here is a forest growth of
Norway and white pine that has not been affected by
lumbering operations. Here also is an Indian village
with its characteristic primitive construction in effective
contrast with that of a modern house that stands in the
same village. Various types of tepees or wigwams are to
be seen, though the covering may be lacking, as it is custom-
ary nowadays to cover the frames with canvas. The
frames, consisting of four inclined poles meeting at a point
with horizontal cross poles, were used in smoking and
drying of meat.

Just beyond the Indian village lies Bare point, where
the darker traps give place to an exposure of sericite schist
which may be traced along the shore for about two miles
(3-2 km.). This outcrop however is not easily accessible
in a launch. At Quarry island the rock changes to a granite
of the same character as that at the Sultana and Ophir
mines.

From the Sultana mine a walk of about a mile affords
an opportunity of studying the contact of the granite
with the Keewatin. Three hundred feet (91 m.) north
of the landing is a pyrrhotite vein about 10 feet (3 m.).
wide, in what appears to be a quartz porphyry. The old
dumps and the mill furnish interesting material for study.

Following a trail from the Sultana mine, the contact
between the granite and the Keewatin and the gradation
from a fine grained granite to a coarse granite porphyry
may be observed. From the summit of the hill above the
Sultana mine a comprehensive view of the northern part
of the lake is obtained. On reaching the Ophir mine
comparatively unaltered specimens of the granite porphyry
may be secured on the dump, where it is also possible to
find specimens of quartz showing free gold.

382

In a southeasterly direction from the Ophir dock
beyond a fishing station and the south end of Sultana
island is Needle point, where the ancient traps have been
so altered that nearly all trace of their original structure
has been lost and they appear as hornblendic and chloritic
schists. Just beyond this point is the old Keewatin mine,

Ellipsoidal trap. Shoal lake.

where the ellipsoidal character of the trap is well shown
as the result of the weathering out of the interstitial
material. These ellipsoids, when fresh, are usually light
coloured in the middle and dark on the borders, while the
interstices are filled with quartz, ferro-dolomite and epidote.
Usually the interstitial material is lacking on the weathered
surfaces.

At the south side of Big Stone bay southeast from the
Keewatin series, some of the precipitous outcrops of trap
show the ellipsoidal structure with the accompanying
ferro-dolomite. The best examples lie between high and
low water marks.

Continuing along the south shore of Big Stone bay
the route lies through Eagle passage and thence in a south-

3§3

westerly direction to Pipestone point, where sericite schist
is prominently developed, likewise an abundance of
ferruginous carbonate which in some cases is abundant
enough to suggest a low grade iron ore. Such an outcrop
is found on a small island just east of this point, where
apparently it has resulted from the alteration of a Keewatin

Metamorphosed sericite schist; Slate island, Lake of the Woods.

porphyry. Another outcrop of this same material occurs
on the mainland east of Square island.

Crosssing Andrew bay from this place a peculiar tepee
made of split logs and covered with brush and earth may be
seen near the entrance to Bottle bay. Entering Bottle
bay the rock is a breccia agglomerate passing into sericite
schist. This is followed by darker traps (on the west side),
some of which are recrystallized and folded over granite
bosses. Farther south the granite bosses are to be observed
without the covering of trap, but occasionally a contact
breccia is seen where the granite has intruded the trap.
These bosses are in the form of 'roches moutonnees' and
have undoubtedly been subjected to severe glacial action,
but the factor determining the resultant form is apparently

3§4

the original shape of the granite boss rather than glacial
action.

On the unnamed island just west of Queer island a trap
dyke of probable Keweenawan age cuts an agglomeratic
sericite schist. Specimens of this rock, showing the fine
grained porphyritic material near the edges and the coarse
diabase near the centre, are readily obtained, but it is
difficult to get good contact specimens. These latter
however may be secured on Slate island, where the same
dyke cuts the same type of country rock, and a contorted
metamorphosed zone about 30 feet (9 m.) wide is present.
This metamorphosed rock closely resembles the rocks
mapped as clay slate, etc., but the adjoining unaltered
rock is sericite schist and agglomerate containing an abun-
dance of carbonates. It is again seen at the contact of the
same dyke on Thompson island, though the adjoining
rock retains the ellipsoidal structure to a greater extent
than on Slate island. Leaving Thompson island the route
lies through the Keewatin channel to the north side of Rat
Portage bay (on mining location K. 85), where highly
altered Keewatin rocks mapped as clay slates, etc., are
well developed on the shore. These are principally horn-
blende and biotite schists, in some places containing an
abundance of garnets and intersected by large veins of
pyrrhotite. These rocks are principally developed near
the contact with the Laurentian granites.

Bibliography.

1. Lawson, A. C. The Geology of the Lake of the Woods

region: Geol. Surv. Can., Ann. Rep.
1885, Vol. I, Pt. CC.

2 The Geology of the Rainy Lake region,

Geol. Sur. Can., Ann. Rep., 1887-8,
Vol. Ill, Pt. F.

3. Coleman, A. P., Second report on the Gold Fields of

Western Ontario: Ont. Bur. Mines, Vol.
V, pp. 47-106.

4 Third report on the West Ontario gold

region: Ont. Bur. Mines, Vol. VI, pp.
71-124.

5 Fourth report on the West Ontario gold

region: Ont. Bur. Mines, Vol. VII, pp.
109-144.

3«5

6. Parsons, A. L. Gold fields of Lake of the Woods,

Manitou and Dryden: Ont. Bur. Mines,
Vol. XX, Pt. I, pp. 158-198.

7 Gold fields of Lake of the Woods, Mani-
tou and Dryden: Ont. Bur. Mines, Vol.
XXI, Pt. I, pp. 169-203.

ANNOTATED GUIDE.

Miles and
Kilometres.

188-3 m. Vermilion — Alt. 1221 ft. (372-2 m.). Eagle
392-7 km. lake another large example of the rock-bound
lakes so characteristic of Pre-Cambrian regions,
is seen at Vermilion. Gold is mined in the
Keewatin schists at several points on this lake.

214-9 m. Dryden — Alt. 1220 ft. (371 -8 m.). Between
345 -8 km. Minnitaki and Wabigoon the Pleistocene de-
posits, either of boulder clay or of stratified clay,
are unusually thick and support a scattered
farming community. At Dryden the stratified
clay is used also for brick making. Gold mines,
including the Laurentian mine, are located at a
number of points in the country to the south
and southeast of Dryden, but none of these are
near the railway.

277-9 m. Ignace — Alt. 1487 ft. (453-2 m.). Keewatin
448-4 km. volcanics
385-9 m. Buda — Alt. 1472 ft. (448-7 m.). and their
621-1 km. schistose
equivalents are continuous from near Buda to
the neighbourhood of Summit, where they are
unconformably overlain by flatlying Animikie
sediments. But from this station to Port
Arthur, a distance of 18 miles (29-0 km.), the
railway traverses a flat delta plain terminating
at Lake Superior, and rock exposures are infre-
quent. In places a red soil has been formed by
weathering of Animikie iron formation, where
that formation lies at no great depth. Al-
though there are no outcrops near the railway,
the horizontal Animikie sediments and the
Keweenawan diabase sills intrusive into them

386

MiomSres form peculiar flat-topped hills not far to the
south. These mesa-like hills are capped by
portions of the horizontal sills, which resist
erosion better than the slates. Mount McKay,
which is seen to the south as Fort William is
entered, is a splendid example of this type of
topography.

426-3 m. Fort William — Alt. 607 ft. (189. m.).
686-2 km.

430-6 m. Port Arthur — Alt. 608 ft. (189-3 m.). Lake
693-1 km. Superior is in sight all the way between these
towns.

PORT ARTHUR TO TORONTO.

From Port Arthur to Toronto the excursion follows the
same route as that taken in the west-bound journey, a guide
to which is found on pages 13 to 36 of this Guide Book
and in Guide Book No. 6.

WELLESLEY COLLEGE LIBRARY

llll llll III II

3 5002 03155 2883

Geological Survey, Canada

Legend
Post Keewatin

Later basic eruptives

Granite, quartz -
porphyry

i i

Laurentian granite
and gneiss

Keewatln

1 * I

Sencite schists

Clay -slate. uuartzite

Agglomerate . coarse
elastics

Horneblende schists and
chlorite schists

Glacial stnae

Route map. Lake of the Woods

Miles

CI.

Geological Survey. Canada.

Gla.cier

Miles

Legend

Glacier and snow-field

Sd I Sir Donald quartzite

| R j Ross quartzite

L I Na-kimu limestone

— J Nakimu limestone

I (mapped approximately)

c ] Cougar format/on

cq!| J (quartzite. metargillite)

jr— -rr, Phy/litic metargillite

Am I Youngest member of Albert Canyon

\y - - division of Selkirk series

Note — Faults not shown on the map

Section

adong

CI.

Geological Survey, Canada..

Structure Section across the Rocky Mountains near the Main Line of the Canadian Pacific Railway
between the Cascade Trough and the Columbia Valley

QE 7-8

165

AUTHORlnternational

■Excursions to Sudbury, Cobalt,

7-8

15 213392

mill 'Mil!

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