18 
BULLETIN 102, UNITED STATES NATIONAL MUSEUM. 
expands and keeps the reservoir completely filled, but at a lower 
pressure. Rock pressure decline is therefore inevitable whenever 
any gas is removed. 
REGENERATION. 
Food and trees can be grown. Water supplies are constantly re- 
plenished by nature, but there is no regeneration in natural gas ; and 
LOCAT/O// OF CHAPMAN 
y/u£ a/at. gas f/fld 
v^CABELL Co. 
WAVTsTC Co. 
-S 
f 
8 
miles 
LO.CAT/O// OF FAST l W// 
AMTL/FAL GA5F/FU? 
-—mu 7/0. 
Cpapmavi 
327 
OLLE 
\ 
% 
L 
\ 
r 
1 
V 
— W£LL//o.473 
5ASTLVAW 
4 
* 
% 
\ 
S 
l 
\ 
\ 
% 
\ 
1 
a 
V. 
F 
V. 
« _ . 
i 
l 
- 4 
* 
t 
4 
1 
8 
K 
S 
' 
*55 
500 
475 
450 
455 
400 
375 o 
q- 
300 § 
M 
£75 ^ 
Uj 
a 
$ 
/75 
/SO 
/£S 
/oo 
75 
50 
as 
o 
FIG. 4. DECLINE IN EOCK PRESSURE OF NATURAL GAS WELLS OF THE UNITED 
FUEL GAS CO. IN EAST LYNN AND CHAPMANVILLEi FIELDS, W. VA. 
when the gas is once used it is gone forever. While no one knows 
exactly how the natural gas is formed, yet enough facts are known 
about it to indicate that nature’s process was a very slow one. It has 
taken millions of years to make the present concentrated supplies, 
and even though gas should now be formed in some parts of the 
earth’s crust, the rate of formation will be so slow as to make such 
new gas pools of no interest or economic value for centuries,, if ever. 
