The circle banner. [volume] (Circle, Mont.) 1914-1939, 1920-05-21
HILL COUNTY OIL
STRUCTURE GOOD
BIOLOGIST SAYS NORTH OFFERS
WONDERFUL POSSIBILITIES >
FOR DEVELOPMENT
Three Wells Drilled Near Havre Sup
ply That Center With Gas; Eagle
Sandstone Penetrated Near Fort
Assinniboine at Depth of 1000
Feet.
BY Charles c. Coulter, GeoIogist

Feet.
BY Charles G. Coulter, GeoIogist
There is at the present time fever
ish interest being manifested in tn
oil possibilities in the north-centra
part of Montana in a region of grea
potential proportions surrounding
Havre, the county seat of Hill county
Three years ago the United State
geological survey completed recon
Nuisance survey of this section, tn
work being carried out under the dir
ection of Eugene Stobinger. Thi
survey comprised an area inc1udin;
Hill, Blaine, Fergus, Chouteau, Tool
and parts of Teton and Cascade coun
ties, and has been of great interes
and vast assistance to the present pet
roleum pioneers who have recently
made their applications for oil claims
under the recently enacted leasing
laws of the government.
The writer had occasion to visit
this field quite recently and several
days were employed in checking uI
the previous work done by the gov
eminent survey, covering principally
the anticlines and faulted structures
as outlined in bulletin No. GAL. 1t is
the intention of this paper to briefly
outline only his conclusions as to the
potential value of the field from a
petrolific viewpoint.
A great glacial drift covers this
whole area, the surface being COM
posed of gravels, clays and rounded
boulders of the pleistocene age. This
great covering conceals much of sub
structural interest, as doubtless we'll
defined oil and gas structure is bur-
led deeply beneath the everything
drift; but it is country wherein the
streams and canyons are deeply cut
and numerous exposures are at hand
to sufficiently warrant the conclusion
that upon the whole it is one of great
Importance from the viewpoint of
petroleum prospecting.
There are noted but two areas of
undoubted anti-clinal character, but
perhaps a dozen additional faulted
or semi-anticlines present,
or it should more reasonably be
stated, perhaps, that now lie exposed
above the glacial drift and that are
of detailed description.
These two cases above mentioned
are thOse of the two parallel Box
Elder (creek) anticlines, as outlined
and carefully traced by Stobinger, To-
Gated some six to nine miles in an
easterIy direction from the city of
Iavre. These structures are best
studied from the flood-plain of Box
Elder creek which enters the Milk
river a short distance north. The
second example is that of the COM
)lete anticlina1 structure situated in
townships SO and "a north, ranges
L3 and IA east.
From the outset the difference in
he trend of direction and strike is
noticeable and doubts |
nay even exist with any one not ac-
Iuainted with the true field condi-
ions as to- the value thereof, owing |
O the apparent lack of continuity of
he formations and tectonic condi-
ions which exist. 1t is not a field |
wherein the formations which con-
rol are badly displaced and it may
e safely stated that every possible
.eologic condition is favorable in
9th fields for accumulation and stor-
ge purposes and that the area of
ach field is sufficient in scope to JUS
fly the conclusion that if oil is pres
mt, it will be found within these res
rvoirs in commercial quantities.
1t is sufficient here to explain that
this region of tilted and
)lded formation that although these
)rmations may be irregular in places
trend and distribution, it should
lso be understood that in but very &
w isolated places is the formation
to such an extent as to rem
or petroleum mining unsuccessful. {
In the faulted areas this condition
$50 maintains in all the structure
udied, more especially in townships s
1 and 35 north, ranges ~, 10 and
( east, where the chances are all in {
vor of successful production, I'M
SIS, of course, displacement or rup- I
re has permitted the escape of the l
Is. These faulted structures are
ON three to 10 miles in length, with
clination of strata running from
We to as much as 80 degrees in 4
aces as shown in the creek and can
IN cross-sections. They are normal il
ID regular faulted structures of a
e thrust type. v
Six or seven wells have been drill e
within this area for water and gas r
It none for oil. A. correlation of e
ese logs enables one to arrive at Il
irly definite estimate of depth, a
ickness of members, continuity of W
rmation as we'll as the chances of G
countering the oil sands at lower Il
rizon. j.
The city of Havre has drilled three fl
s wells which now supply the city il
tn gas. At Assinniboine, five miles te
nth of Havre, we'll was drilled 81
water in 1893 to depth of 1900
It which penetrated the Eagle sand
me. A we'll drilled for gas by the H
vre Natural Gas company in 1915 10
section 33, township 33 north, tn
lge 16 east, some two miles east of 81
vre is CAT feet deep and at the tn
tom undoubtedly encountered the WI
gle sandstone. This we'll obtained in
100000 cubic feet of gas each "a
lrs, having an initial closed pres fe
e of 499 pounds to the square en-
h. In
This we'll penetrated the glacial or
~ thu v,pIor1u3no Judith Piuorl a III