Montana oil and mining journal. [volume] (Great Falls, Mont.) 1931-1953, 1939-09-09

STARTLING" INFORMATION

There is oil in the Devonian in the
Sweetgrass Arch.
This is a startling statement, when
made as a statement of fact yet it is
not startling to anyone who has fol-
lowed the history of the oil industry
There were probably some who were
surprised at the news last week of oil
in commercial quantities at Vermillion,
a relatively short distance north of the
Montana border and in the geological
formations identical to those in Mon
tana But it is not surprising news.
For many years the Midcontnent oil
operators thought that the Kevin-Sun-
burst horizon, the top of the "big lime"
was the basement of production. When
a well was drilled to the top of the
big lime" it was either a producer or
a dry hole.
That is the rule in Montana today. If
a we'll does not find oil at or above
the Madison lime, which is the familiar
"big lime" of Missssippian age, it is
abandoned Yet some sof the greatest
oil fields in the world have NO produc-
ion in horizons above the big lime. The
fact that a structure is so sealed that
the oil does not escape upward through
the big lime to collect beneath imper-
vious shales of the Jurassic and the
Cretaceous beds, is regarded as most
favorable to large production.
We see Illinois producing 100000 bar
rels per day for the reason that some
one discovered that the DEYONIAN car
ries oil in Illinois. Except for the
science of acidization, this Illinois de-
velopment might not have been so rapid
but the combination or deeper drilling
and acidization has made Of Illinois
great oil producing state.
Before this new development, Illinois
had less production than has Montana
The outlook was far less promising be-
cause Illinois does not have as many
sharply defined structures as Montana;
nor is there so much petroliferous area
in Illinois as in Montana. At the pre-
sent time the state is producing some
thing like 10000 barrels per day. OF
this less than 5000 barrels is coming
from the OLD fields.
How long are Montana oil operators
going to follow the ancient rule that
the top of the white lime Is the stop"
signal for drilling. There are dozens
of wells in Kevin-Sunburst field which
were abandoned in the early days that
might have been producers today had
they been actually drilled into the top
of the Madison lime. They were stopped
by drillers who had been told to quit
as soon as they encountered WHITE
LIME. Many of them quit while they
were still in the Ellis: never did reach
the Mssissippian lime.
When Gordon Campbell first went into
the Sweetgrass Arch and spotted his
initial well north of Kelvin he wrote a
report which was published in the Jour
nal and in other newspapers and trade
magazines stating this belief that the
source of the oil in Montana and Alberta
is IN THE DEVONIAN. Since the De-
vonan had never been tested it was
apparent that Gordon Campbell was
working on a THEORY rather than a
known fact.
But now it develops that the exposed
Devonian beds upturned in the Rocky
Mountains show that the Devonian is
PETROLIFEROUS. Wheth-
err he had seen these sections, we do
not know, but 1T is now apparent that
Mr. CampbeIls theory was based on
more than guesswork.
Up in Alberta many operators drilled
70 the top of the Madison lime-which
became known as the Montana oil pro-
iucing horizon-and then stopped be-
,ause it was the rule to stop whenever
he white lime was encountered. But