The pioneer-review. [volume] (Philip, Haakon County, S.D.) 1920-current, 1921-06-23
AUTHORITATIVE INFORMATION
CONCERNING C1t.

One Of our local friends has
been pulling over the oil geolo,
g.sls lately, and furnishes us with
some interesting facts about oil
and oil production.
/ The origin Of oil is one problem
its accumulation into economic de,
nosits an entirely different one
More is known about the accumu-
Iation Of oil than about its origin
Commercial oil and gas DEPOSITS
generally occur in the higher parts
or folds or wrinkles in the earth's
surface called anticlines. dones
and monoclines.
Water is generally found in the
same startum as the oil, but in
the lower part Of the fold.
All commercial deposits with
one exception, that of ThralI, Tex,
SO far have occurred in sedemen-
tary sandstone conglomerates, in
shaIcs or limestones.
All oil and gas deposits, so far
as known, are capped or covered
by practically impervious beds Of
shole, Of sandstone of limestone.
Also such deposits are underlaid
by impervioun beds.
Many people think of lakes Of
oil lying underground. This is not
the case by any means. The small
voids in the sands afford plenty
of space in which oil. may accum-
late. Some sands contain 20 per
cent voids (they vary from tc
35 per cent? If these voids were
full of oil, each 100 cubic feet OF
sand would contain 20 cubic feet
Of oil. A bed 100 feet thick would
then contain 155,5z1 barrels.
The area drained by one we'll is
varlously estimated at from one
to ten acres. Some operators
space their wells 100 TO 500 fee
apart, varying the distance inver-
sely with the richness of the SANDS
No rule can be set, IS the porosity
Of the said, the gas pressure. and
the dips vary greatly in difereat
fields. At Beaumont, Texas, on
one field wells were drilled so close
that the derricks overlaped. In
some of the Gulf coast fields three
thG four wells per acre is not un-
usual. Leases from ope-acre tracts
have been sufficient to make for
tunes, but from the best operating
standpoint such leases are waste
full.
In the eaerly days of the oil in
dustry, drilling was carried on in
an unsystematic manner without
any regard for geological features.
It remained for an American geo.
logist, |. S. White, in 1885, to give
us the clear outline of the appli-
cation of geological methods to
the finding of oil and gas fields
and to the locating of wells. Prac
tical men remained skeptical, and
iy the later conditions of the oil
industry and a consequent employ
ment of the geologist's services in
large numbers with the results
they have achieved, convinced
them that geology is more impor-
tant by far than the first enthus-
last thought. As a result the
chance for success of prospect
wells has been reduced from one
in hundred and fifty to one in
three. Every large company now
maintains a geological staff.
While production has increased
from 250,000,000 in 1913 to $780,
100000 barrels in 1919, consump-
ttion has increased much more ra-
pidly. 1t is estimated that con-
sumption has doubled in the past
forr years, and now exceeds pro-
duction by nearly Is per cent.
This excessive consumption causes
serious concern. especially because
our known fields are rapidly near
ing exhaustion.