The Ely miner. [volume] (Ely, Minn.) 1895-1986, 1901-12-13
Iron Ores Of Lake Superior.

tile report of the United States geo.
logical survey ON Canadian ore de-
pOsis.s OF the Lake superior region.
for anything bearing on the probable
future of Canada as Il producer of iron
ore. especially to the north of Mime
sofia and Lake Superior. will have u
! bearing of Utmost importance on the
ore supplies Of this state. Following
is All extract from the forthcoming
report of Professor G. r. Van Hise.
| Tile Notwithstanding series
has been traced by us to Hunters
Island. Thence these rocks has been
| mapped by the Canadian survey as
extending i'm Il northeastern and then
in al easterly direction to the Kam-
inisllquia river, and thence eastward
To the Keweenawan rocks west of
Lake NipigOn. Another great belt of
| irOn-bearing with various ramiticat-
ions has been traced by the Canadian
survey from Rainy Lake eastward to
the Canadian Pacific railway aud to
| Lac DIES Mile Lacs. III this belt Oc-
ours the su-called A'iknkan range. in
which large deposits of iron ore are
said To Oll:crOp.
East and north of the east half OF
! Lake Superior various areas Of IRON
bearTng rocks are also found. One or
more belts are said to extend east
frpn Lake Nipigon. A belt is found
adjacent to tho Black and Pic rivers.
Several bells Of iron-bearing format-
ion have been found i'm the Michipi-
colen dist riot.
AT the present time the only one of
these districts which is an ore pro-
ducer is the Michipicoien. While
This district has not been connect ed
areally and slructurally with any
her area in The lake region, the
likeness in the character of its rocks
and The Succession to the Vermiliun
district leaves little doubt in my
mud that the two districts are in
most essential points paralled. In the
MIcliipicoien district the basement
rock is IL greensboro, showing the
ellipsoidai structure on the great
Stale SO characteristic to the Ely
greensboro of the VermiliOn district.
Also with this greeI>tnnea various
Iolher mashed igneous rocks, includ-
ing porphyries. The iron-bearing
f64'fiaai ion i'm many essential respect
resembles that of the Vermilion
/ district. It. contains substantially all
The varieties of material in the iron
formation of the Vermilinn district.
aud in addition great quantities of
pyrilic quartz rock. On The bluff
back of she Helen mine and at many
OF her places. iron carbonate is abund-
ant. Near the Helen mine Mr..
Merriam reports this carbonate as
containing 10 to 81 per cent, of
metallic iron. At the present Lime
The iron formal ion has been develop
geod body Of ligll-grade hemaiiie has
been shown by stripping 10 extent in
considerable areas To he rock surface
| In 1900, the first year of shipment.
62. 000. tons were shipped. Whel her
Or not the Micllipicoten district will
be great producer in lie future can
not be told, of course in advance of
development
a further analogy between lie Yer
million and MichipicOten districts is
furnished by an upper series in the
latter district consisting of mashed
coliglonerateS aud salies, the former
bearing very numerous fragments Of
The lower series, including HE iron
bearing formal ion, precisely as in the
Verlnilion district.
AS vet the various districts which
may bear merclantable iron in guam
tit, have been outlined only in the
most general way by the Canadian
survey, but the reconnaissance, re-
ports descriptive"f them. show that
both Archean and Lower Huronian
rocks occur. and that at least The
Arcllean irOn-bearing formation
exists. The Canadian survey has not
attempted to separate the iron-bear-
| ing formations from the associated
rocks. Doubtless in the future, the
iron-bearing formati ions will be separ-
ately mapped. When this is done it.
will undoubtedly he very helpful to
the Development of the iron. ore
resources of this region.
With one possible qualification. SO
far as one can see. here is no known
geological cause why iron ores should
not extensively exist on the Canadian
81 lie of Lake Superior. This qualitica-
tion is due, 10 glacial erosion. In This
paper it has plainly appeared that
t he iron ore deposits are products OF
the surtical belt, and that they were
formed mainly in pre-gIacial times.