Montana oil and mining journal. [volume] (Great Falls, Mont.) 1931-1953, 1938-06-11

There are relatively few people
who grasped the significance and
Importance of the announcement
last week of we'll to be- drilled
CD on a location selected by
geophysical survey, and
(2) with the Devonian as the
objective.
This well, to be drilled in Pen
droy district, is the first in Mon
tana to have the advantage of ge-
ophysics and horizon below the
Madison lime as its objective.
The opinion of the operators with
whom we have talked is that the well
will not likely reach the Devonian, as 1t
is so highly probable that commercial
oil production will be found at the top
of or in the Madison limestone.
Those who know the history Of OIL de-
yelopment in the Midcontinent will nope
and pray that this well continues on down
to the Devonian, for it Is believed mat
here. as elsewhere, the real history OF
Montana oil will be written on the pro-
duction of horizons BELOW THE BIG
LIME.
Except for deep drilling there would
no shortage of oil in the United States
today Except for seophysicR, there would
have been few new fields added TO the
countrys reserve for eight. out OF ten OF
new discoveries in the past five years
have been through geophysical methods.
Geophysics are esta blished as the method
of oil we'll location in practically every
other state than Montana. 1t has greatly
decreased the hazards of oil prospecting
just as geology decreased the hazards
against the trial-and-eIror methods that
preceded the evolution of the anticlinal
theory
Geology and geophysics now combine
to locate structures and to survey the
sub-surface conditions which were mere
tofore hidden from the eye OF the geo
logist except through expensive drilling.
We regard it as highly impossible that
any important wildcats will be drilled In
Montana in the future without geophy-
steal guidance in locating the test wells.
Members of this organization all grasp
cd the significance of the news for they
are alert to the forward strides of the
industry taken in recent years in geo
en- drilling There are few
who do not believe that the oil found in
Montana thus far is coming FROM Be
LOW THE BIG LIME. Accumulations at
the ton of the lime merely indicate the
location of the source of the oil. Nor
are they alone in this belief. The taet
the great production of the Mldcontnent
comes from deep drilling to horizons be-
low the lime is adequate evidence, with
ont considering the fact that Turner Val
ley is producing from horizons from 400
to 500 feet deeper than the. top OF the
lime and that oil production IN THE DE-
WOMAN has been found in Alberta struc-
lures which have formations identical
with those in Montana.
The United States Geological Survey
has compiled the best information about
the little-known formations below the
Madison lime. Because of the coming
test. we here reprint some of the ex-
tracts from U. S. G. s. Bulletin S12 deal
ing with formations below the big
lime"
L. S. G. $. REPORTS
The distribution of the oil Tin kevln-
Sunburst) may be due in part to its
source and method of migration. The
small assures noted in the Troy-Sweet-
grass we'll may be parts of fracture zones
or even faults which reach down into
the Devonian formation and through
which the oil reported in that formation
may be collected at the base of the Ellis
formation If this could be definitely
proved to be the source and method of
Of what value iS valuable