Montana oil and mining journal. [volume] (Great Falls, Mont.) 1931-1953, 1942-11-07

seems hardly possible that even where water
flushing was active all parts Of this sand
could be swept clear of oil by circulating
waters. In the writer's opinion, therefore.
MORE OR LESS OIL MAY BE IRREGU-
LARLY DISTRIBUTED OVER CONSIDER
ABLE AREAS OF THE SWEETGRASS
ARCH OUTSIDE OF THE PRESENT
KEvN-SUNBURST FIELD.
The waters present In the Kevin-Sm-
burst field commonly contain more or less
hydrogen sulphide gas, which gives them a
characteristic disagreeabIe sulphur" odor
and analyses Of the water show that it is a
somewhat modified sea water that was pre-
sumably buried with the sedimentary rocks
in which it Is now found
Thereafter follows discussion of analyses
Of the OIL all of which applies equally to
the new lime production areas Of Cut Bank
as well as to Kelvin. Space does not allow
reproduction of his full discussion Of POS
sible Sources of the OH" but these para
graphs have interest in the light OF the
Twin Rivers discovery:
"Showings of oil have been found in small
vertical assures in the normally compact
Madison limestone, and parts Of the Madi-
son core of the Troy Sweetgrass as wen had
the pronounced disagreeable sulphur odor
chacteristics of much of the Kevin-Sunburst
oil.
"A considerable quantity of black heavy.
dead" oil is reported to have been found
near the base of the Madison limestone IN
the Dry Fork well, north of Conrad, ia Sec.
2-28-3W Showings Of oil and hydrocarbon
gas as wen as disseminated oil are reported
from the Devonian rocks penetrated by the
roy-Sweetgrass and Frazier wells, IN the
Kevin-Sunburst field, and the Bearsden
well, northeast Of east Butte The Athabaska
tar sands, 400 miles north of the Kevin-
Sunburst oil field, which lie just above the
Devonian, the oil found at points farther
north in Canada; and the oily odor found
in the Devonian limestone Of the Little
Rocky mountains all lead to the belief that
the Devonian contains a considerable
quantity Of oil and may possibly be the
source of the oil of the Kevin-Sunburst
field.
Considering the great thickness of the
Madison, the oil found in the-E1lis forma-
ton, if derived from 1t, may have been
greatly concentrated If the oil was derived
from the Deyonian rocks it must have
migrated upward at least 800 feet, presum-
ably through fractures in the massive hard
Madison limestones 1t is possible that the
Madison limestone does not extend far
north on account of erosion or nondeposi-
lion, and that the oil there migrated from
he Devonian to the base of the Ellis forma-
ton and thence southwark along the I'M
for many miles.
after deposition, pressure would drive
he oil from the shale to the more OPEN
textured rocks, where If water were absent
It would sink down and accumulate IN
he lowest places available If water were
present under a hydrostatic head the oil
would rise into the highest openings avail
lble, moving along bedding planes to the
ops of domes or anticlines; or if the over.
ying impervious rocks were fissured or
aulted it might cross the bedding planes
o the tops of domes or anticlnes; or If
he everything impervious rocks were 1sSured
II faulted it might cross the bedding planes
o higher sands The presence of artesian
vater in the Madison limestone in many Of
he wells of the Kevin-Sunburst field makes
/ seem improbable that oil from the
or Colorado formations could have
migrated downward and accumulated in
he Ellis shale The oil therefore apparently
originated in the Ellis formation or in the
ormations below it.
as a copy Of the US.G.S. contour map of
he west Kevin-Cut Bank area On that
nap is shown the Twin Rivers nose where
IL has been found In the Madison lime.
We ask those who read this article to get
ut his map and look at the other folds
nown
/. Next to the Twin Rivers fold, on the
asst, is broad fold known as the Blackfeet
Tose The Reagan horizon has not been
ssted on this fold.
O. Next east Of the Blackfeet Nose is a
larp fold known as the Hay Lake Nose on
hich is located the Darling pool which re.
ects the sharpness of the fold by having
i and gas production in three horizons.
he Reagan horizon has not been tested on
lis fold.
g. Next, east of the Hay Lake fold is the
order Red Coulee fold.
Does it seem probable or possible that
lese other folds do not contain oil?
All of them are higher, structurally, than
lie Twin Rivers fold where adequate hydro
attic pressure is shown to trap oil in all
these higher folds.
with the discovery well on Twin Rivers
owing so barrels per day, proving that
Iere is a substantial oil field on that Nose,
, these facts, coupled with the USG.S.
scussion of causes, not point to some new
"A y1oeefhIv greater Onnnrtirnities9