1124 M1NEBALS YEARBOOK, 1941
County, was completed for 12 mfflion cubic feet a day from a total depth
of 1,717 feet.
 Repressurmg with gas of the Jones oil sand m the Shuler field began in 1941
under a unit operating agreement fostered by the State regulatory authorities
By this means gas will be conserved, and recoverable oil reserves are expected
to be increased materially.
 CaliJornia.—FOr the first half of 1941 marketed production of natural
gas in California was 184,554 mfflion cubic feet, a 7-percent mcrease over
the comparable 1940 period The source of mformation is a report from E. F.
McNaughton, California Railroad Commission. The volume of gas reported blown
to the air—17 1 billion cubic feet during the first half of 1940—was
reduced to 7.3 billion for the similar period in 1941 after the peak of flush
oil production at Montebello had passed.
 Discoveries in 1941 included three oil fields with relatively high gas :
oil ratios—Raisin City and Riverdale in Fresno County and Helms in
Kings County. Large gas reserves were proved at Raisin City. A new dry-gas
field of undetermined importance was discovered 12 miles southeast of the
Tracy gas field, San Joaquin County, The gas comes from a thin sand at relatively
shallow depth. Several new productive zones were discovered in fields throughout
the State. The Paloma gas and "condensate" field was extended west and southeast.
On March 24 all producing wells in this field except dry-gas wells were shut
in to eliminate excessive waste of gas and pressure drop pending adoption
of a unit plan of operation for gas injection and pressure maintenance. The
wells were still shut in at the end of 1941.
 In the Cole's Levee field important gas production was developed in 1941
about 3,000 feet above the oil-producing formation. Gasutility pipe lines
are conveniently near this field.
 Completions in gas fields during 1941 numbered 18,~of which 14 were at Rio
Vista, 2 at Vernalis, 1 at McDonald Island, and 1 at Delano. In addition,
3 gas wells were reported at Cole's Levee, I at Union Avenue, 1 at Elwood,
and 1 at Santa Fe Springs oil fields.
 All rights to the La Goleta gas field were acquired in 1941 by a utility
company. Large compressor units and other equipment were installed to prepare
the field for use as a gas storage reservoir.
 The increased demand for gas resulting from war activities has strained
the capacity of some gas producing and transmission facilities. To guard
against critical shortages of gas, the California Railroad Commission instituted
a general investigation cOvering the State gas reserves, consumers' requirements
and the ability to meet them, and the economic factors relating to industrial
use of gas as opposed to oil or other fuels.
 CYolorado.—Natural-gas production continued to expand in 1941 to 2,713
million cubic feet—30 percent above the 1940 output. The data are taken
from a report by L. G. Snow, acting supervisor, Geological Survey, United
States Department of the Interior, Casper, Wyo. Withdrawals from the Powder
Wash field were begun in June 1941 after an outlet was provided by laying
an 8-inch line connecting with the Salt Lake City transmission system in
the Hiawatha field.
 The Powder Wash production was 477.3 million cubic feet. Hiawatha and Thornburg
production increased to 1,996.6 and 114.2 million cubic feet, respectively.
The output of other fields declined and was as follows, in millions of cubic
feet: Berthoud 50.4, Craig