Democratic Northwest. [volume] (Napoleon, Ohio) 1869-1894, 1890-01-02

III NOW AOrh rIluiy NJ tne meeting OF the
American geological society Prof. Edward
orion, State geoloRist Of Ohio, discussed tht
Origin Of the Rock Pressure of Natural Ga,
in the Trenton Limestone of Ohio and In.
diana. He said: Natural gas derived from
the trenton limestone has supplied durino
the last year, and is now supplying, all the
fuel and considerable part of the artificial
light that Is used by at least 100000 people
in northwestern Ohio and in central Indiana,
Within the same limits it is the basis Of q
varied line of manufactures, the annual
product of which will make an aggregate OF
many millions of dollRrs.. More than fortJ
glass furnaces, not one of them thres
years old, are now in very successful opera
| ton within the territory named, while iron
and steel mills, potteries and brickworks and
long list of factories, In which eheaE
power is desideratum, have been built ur
on all sides with wonderful rapidity.
lime stone that has yet been reached is to be
credited to the present year. A we'll drilled
at Staurtsville, six miles north of Findlay
early last summer, produced through the
casing, pipe 55sinches in diameter, 28,OO0,
600 cubic feet Of gas every twenty-four hours.
There are but few wells in any fields that ex.
ceeds these figures. Most Of the wells that
have been so reported have been estimated,
not measured. An equally astonishing ad.
this rock, within four counties Of northwest
ern Ohio. Single wells during the last year
have begun their production area rate of TO-
600 barrels day; and more than 100000 bar
rels of total production are already to be
credited 70 single wells of the new Geld, while
#asconsiderAble a number have passed the 1O0,-
200 barrel mark. stW sgE
The rock pressure Of the gas is a vital fac
tor in all this production. To its energy is
due the propulsion of the volatile fuel from
the wells where it is released through twenty,
thirty, fifty miles of buried pipes to the
cities, which it supplies with the unspeakable
advantages of the gaseous fuel. This is the
same cause that lifts the oil from the rock in
all flowing wells. By rock pressure ia meant
the pressure which q gauge shows in well
that is locked in after the drill has reached
the gas reservoir. The iron tubing of the
we'll becomes by this meanA part of the
reservoir, and the same conditions as to pres
sure are supposed to pertain to it that are
found in the porous rock below. The rock
pressure OF gas varies greatly in different
extent, in different portions OF the same field.
The highest rock pressure recorded in the
trenton limestone isabout $50 pounds to the
square inch, while there are considerable
sections OF the gas territory that never reach
3OO 20 lnds pressure per square inch. The
original pressure in the Findlay field was 45O
pounds, varying somewhat in wells of DIFF
terent depths. In the Wood county field,
from which the largest amount of gas is now
being conveyed to Ohio cities, the original
pressure ranged from 42O to 460 pounds, the
general pressure being counted AGO pounds to
the square inch. There were occasional
records made Of higher pressures still in
single wells; but Of such cases the number ris
very small and the existence of these incred.
uious pressures were short lived. In the In
diana field still greater reduction of rock
pressure is noted. The range Of the princi-
pal Indiana wells Is between $50 and 325
pounds to the square inch. The Indiana gas
wells, as compared with the Ohio gas wells,
are marked by reduction in total depth as
well as in rock pressure, the figures for depth
In the productive territory seldom or never
passing 1000 feet. -
Prof. Orton discredits the theories that
rock pressure is due to the weight of the over
lying rocks or to the expansive force Of the
gas. He thinks that the rock pressure of gas
in trenton limestone of Ohio and Indiana is
hydrostRtic in its origin.
'Sagacious operators" he says, are ''be-
coming satisfied by their own experiences
that the root of rock pressure ia to be found
in the water column that stands connected
with the porous rock in which the gas and oil
are contained. When the drill decends into
the gas rock proper dry gas escapes, when
into the contiguous and lower lying terrace,
oil, accompanied by the gas, appears; but at
q little lower level salt water ia struck and
This rises promptly in the we'll, sometimes to
HE point of overflow. Farout from the mar
row ridges, or restricted terraces, where gas
and oil are found. the salt water reigns undis- |
turbed, and whenever drilled to it, rises in |
The wells as those already described. The !
rise of the salt water is Enthusiastically ar |
tesian. 1t depends on hydrostatic pressure, |
Is does the flow of all artesian wells, and its !
head must be sought, as i1i other like flows,
IN the higher portions Of this structure that |
ire contiguous. The nearest outcrops OF this /
porous trenton are found in the shores of
ieet above tide. It is certainly significant
hat an abundant flow of salt water is struck !
n boring in norih hern Ohio or in Indiana. No
natter at what depth, it rises generally to
he level of Lake Superior, or, in other words, |
.bout 100 feet above tide. II the month of !
he well is below this level, as in the cases of (
he Wabash valley, the salt water overfows.
rhe height to which the salt water rises in |
my portion Of the field is one of the ele-
nents to be used in measuring the force
which can be exerred on the gas and oil that |
re caught in the traps of the terraces and !
riches of the porus trenton limestone. The |
ock pressure of the gas differs Rt the various
,oints, because of the difference in depth of
he rock below sea level. The rock pressure
# trenton limestone gas Is due to salt water
olumn measured from about 100 feet above
ide to the level of the structure which yields
he gas. There is no danger that the great
as reservoir of to-day will 'cave in or blow
p' after the gas is withdrawn from them. '
IN y 80 r.