Montana oil and mining journal. [volume] (Great Falls, Mont.) 1931-1953, 1941-03-01
NORTH MONTANA GEOLOGY

MOntana-"The Land the Shining Mountains
much of its wealth to the Rocky Mountains Ii
was the uDheava of these mountains that brought the
treasures of the earth the within the reach
of valiant persons who have the daring TO dig or
drill for them.
MOntanans are more richly blessed than people of
many other states, for Nature only deposited pools
of oil and gas TO enrich the finders but furthermore
erected signpOsts direct way their discovery
In MANY oil states there are few surface Indications
of structural traps which might contain oil. But in
Montana a schOObOy can go forth and find signs of
structural conditions which may point toward the dis
cOvery of an oil pool
Throughout the ages, Montana in common with
Alberta has been alternately covered by water and Icy
dry land. The uprising of mountains is followed by
the long period of erosion I'm which the mountain
rocks reduced TO silt and sand and washed down
to fill lower levels. The process has laid down
series of beds of sands shales representing the
land formations and lines representing the bottom OF
an ocean These alternate beds varying in color
in fossil life, have been classified into ages
"CretaceOus," "Jurassc,r "FaleOzOic,' etc, and
the divisions thereof have been named Colorado
shae," "KOOtenai shaIe' madison lime etc.
These alternate beds be and measured in
the mountains where the gigantic suberranean forces
have upheaved these beds that the full section can
be examined by who win into the mountains
Rocky Mountains upheaved these horizontal beds
and in so doing provided Montana and Alberta with
vast riches. That mountain upheava served to ~
buckle the earths surface into folds structures;
(2) provided the heat and pressure which is be-
eved TO have distaed petroleum from the rich shaes
Of the sedimentary BEDS
(S) provided an intake Tor water winch mas Deeh
pouring into porous sands which stand exposed TO
eternal rains elevations high above the
plains and which provide lsydrOstatic table (water
leveD for the lOwlands;
a. provided headwaters for surface drainage
channels which have erOded away thousands of feet
of sediments much of the of Montana.
Thus the river valleys have deeply into the
formations, revealing the tilted rocks which point to
the buckles folds in the earth's surface Once
geOlOgist finds shaes dipping away In four directions
from common point he knows that he has struc-
which may oil trap. He knows that
oil water; that the oLbearing formations
present; that water may have forced the oil mp
into the trap"
To determine a definite closure" is the problem
OF a skilled geOOgist who with modern science can de-
termine whether the trap is complete is "Open
which latter situation would allow the oil TO be driven
ON ahead of the water, into another fold or trap
slightly higher. Water seeking its level always
the oil into the highest point thus the neces-
sity for a tight zeal enclosure.
Combine OilfOrming materials with sandstones or
porous lines plus water pressure, plus perfect anti
cline dome (trap) and on field is possible
Thanks to the Rocky Mountains Montana has SCORES
Of INFESTED structures where these conditions may be
found to be present