Montana oil and mining journal. [volume] (Great Falls, Mont.) 1931-1953, 1939-10-14

lis not the surface 10 million years
hence; 10 million years is but sec
ond when measured by the hands of
the geological clock.
Since, therefore, the surface is a
transitory and a more or less acct
dental, warped surface, that intersec-
tion-which we call and outcrop-be-
tween the surface and the vertical
dimension of a more or less tabular
vein standing at high angle Is mani
testify a geological accident. Thus, ex-
cept for that type Of metalliferous
vein which is a near-surface phenom-
enon, there is no particular reason to
suppose that If the surface in metal
liferous region we're a thousand feet
higher than 1t Is now or a thousand
feet lower than it is now, the number
of outcrops would be notably greater
or less than 1t is at the surface as we
know 1t in metalliferous regions today.
I am speaking, of course, of veins
which show definite depth-persis-
tence. 1t follows, therefore, If I am
probably almost as many blind veins
yet to be discovered as Of outcropping
veins which have been discovered to
date.
Conditions Favorable
"All this, of course, is true only of
areas in which the conditions for the
deposition of ore are favorable. Do
you know what these conditions are?
think we do. We have at Montana
School of Mines a relief model of the
entire state on which the various geo.
logical formations are painted in diff
ferent cOlors. Granite, in accordance
with the usual custom, Is colored red.
AS I look at the relief map, I see two
large red areas. One is that portion of
the Idaho batholith which extends into
Montana. This lies mainly in Mineral,
MiSsoula, Ravalh and Beaverhead
counties with an CUTLER extending up
into Granite and Deer Lodge counties
the Philipsburg batholith. The sec
ond large red area touches Beaver
head, Silver Bow, Jefferson, Deer
Lodge, Powell and Lewis and Clark
counties with a sizeable granite CUTLER
in the Tobacco Root mountains in
Madison county. This Is the Boulder
batholith, and always In the vicinity
of mountain upliftS are other little red
spots extending as far eastward as the
Moccasins and the Little Rockies. All
of these red spots on the map are in
general areas in which, or near which,
metalliferous deposits of greater or
less significance should occur and do
occur. Thus, the favorable conditions
for the occurrence Of ore bodies exist
in Montana, In numerous places.
Constantly keeping In mind that
outcrops are accidental occurrences
and that favorable loci are numerous
throughout the state, particularly In
the western third of it, there is every
reason to suppose that further signifi-
can't discoveries of gold, silver, copper,
zinc and lead win be made as soon
as we have the tools and the knowledge
with which 30 make them, or with
which to predict the places where they
should be sought for with the drill or
by geophysical prospecting or by other
aids which win undoubtedly be dis
covered"
Chromite Deposits
This inadequate review of the situ-
alton would be still more inadequate
If it failed to mention one of Mon
tana's most important and, as yet,
largely undeveloped metalliferous re-
sources, namely, the chromite deposits
Of Sweetgrass, Saltwater and Carbon
counties. This chromite belt" can be
traced for more than 90 miles along
the surface and Is exposed vertically
over a range of 1000 feet or more.
Montana chromite Is at present largely
lIndeveloped by reason Of competition
from foreign sources, but "a hours
after we became engaged In war, this
resource would receive immediate at
tention. Let us hope that we will be
wise enough and enterprtsing enough
to develop 1t without the terrible holo-
cauSt Of war. Manganese Is another
significant war-mineral resource which
has a future as well as a past. SO
much then for the future of the in
dustry.