Montana oil and mining journal. [volume] (Great Falls, Mont.) 1931-1953, 1940-09-21

n recent weeks we have been making
a careful study of production his
n tory of the high gravity pool Of Kew
in field, west of the town of Kelvin, and
the thing that has impressed us most is
our high regard for the first structural
contour map of this area made in June,
1924, by Fred X. Houston geOlOgist,
of Helena.
Houston made a contour map of this
area before any wells were drilled 10
give him sub-surface data. We have gone
over the ground and have checked the
exposures shown on his map, and we are
led to marvel at the accuracy of his de-
auctions, because wells drilled in later
years confirmed his geology. We do not
know Mr.. Houston personally and he has
had no part i'm subsequent north Mon
tana oil development of which we know,
but we of the opinion that he might
have rendered the state a great service
had he remained in petroleum engineer
ing.
The early drilling in the high gravity
pool was based on HOustOn's map and six
wells were drilled, in 1925 and 1926
We have some recollection of the drill
i'm of these wells but we were not inn
pressed by the results because that was
the time when Rice and Fulton and Fer
dig and others were bringing in multi
thousand-barreI wells in the East pool
and a 5O-barreI well was not a drop
in the bucket in public interest.
In checking over the records of these
wells we were surprised not only at
the accuracy of the map but we were
surprised to learn that among the six
wells drilled ON HOuston's high We're
two wells rated by the Northern Oil
Information Bureau at so barrels each.
A. @,r SN.ak aud
barrel wells, In natural production, are
considered very important in this pool
tOday-nOw that we have the science of
acidizatiOn-it makes us wonder wheth-
or the true worth of the high gravity
pool has yet been determined.
In view of the fact that little oil was
taken from the wells drilled, it would
seem that much of the original ''head"
of oil is still present Furthermore, there
would be no production i'm the high gray-
ity pool today except for modern pro-
ductiOn practices-not only acidizatiOn
but also the science of producing wells
with back-pressure.
To illustrate what we mean, we re-
call the history of the RimrOck dis
cCJVery well This well was a sort of
jack operation, financed and carried out
by a group of Kelvin operators who be-
lived that there was a local high" as
mapped by Houston and who believed
that the shOwings of oil in the old aban-
doned wells were adequate to encourage
the idea of using acid in the territory.
These men, including e. l.. Postlewait
Charles Rider and other operators who
are Thorough students, worked out the
project and it checked out nicely; the
well showed oil I'm a lime that responded
quickly to hydrOchlOric acid. However,
after it was acidized and put ON the
place came a quantity of FRESH water.
Elsewhere in the field, sulphur water is
found at the top of the lime, but here it
was fresh water.
These operators recognized the unus-
uaI condition and decided to attempt to
exhaust the water so they pumped hard
and after few weeks 1t began showing
volume of oil equaled the water, then
exceeded the water and the water
well" suddenly turned into a flowing oil
well, making 100 barrels per day. That
was four years ago in 1896. That well
Is today making so barrels per day.
These operators experimental with var
ious production methods, to hold back
the water, and they determined that they
could do so by using BACK PRESSURE
on these wells. Six wells have been drill
ed by the RimrOck, five of which were
producers. These wells have been pro-
duced with an average of az pounds of
back pressure. Heretofore ali wells In
the field were produced with the