The history of development in Oklahoma during 1939 was in many ways a repetition of the preceding year.

Total production of oil for the state during the period was 153,500,000 barrels, a decrease of 9.7 per cent from the total of 170 million barrels withdrawn during 1938. With a total 2,065 wells completed during 1939, drilling operations were slightly above the preceding year. Well completions were rather widely distributed throughout the pools of the state, with no concentration of development in any particular area other than the usual preponderance of drilling in the general Seminole plateau province.

The Oklahoma City and Fitts pools continued to lead the state in total annual field output.

There was little change in the amount of geophysical exploration work being carried on throughout the state, but in contrast to the policy of the preceding year, operations were confined largely to outlying wildcat areas.

The number of wells which might be considered as wildcat or exploratory tests increased somewhat during the year. Of the total of 2,065 completions, 268, or 13 per cent, have been here classified as exploratory wells. As a result of this comparatively large number of extension and wildcat tests, 31 new pools and 29 extensions and new zones were discovered and several rather important outlying dry holes drilled. Of the 60 new discoveries, 35 were in Pennsylvanian sediments, 11 in Siluro-Devonian, and 14 in the Ordovician. Few of the new pools were of general importance and none was conspicuous for extensive development during the year. The most important discoveries were perhaps the Hobart pool, in Washita County, the Byars pool, in McClain County, and the Arbuckle zone, in the Frederi k pool, Tillman County. The Pure Oil Company's Little well No. 1 in the Cumberland area, Marshall County, which was not completed until March, 1940, and is not included among the 1939 discoveries, may have opened one of the most important new areas discovered in the past 5 or 6 years.

While numerically impressive, the new discoveries during 1939 did not add greatly to the Oklahoma total reserves. As in the several preceding years the annual withdrawal exceeded the estimated total of the newly discovered reserves by many millions of barrels. The faith of the wildcatter in Oklahoma's future is, however, still strong and the year closed with many outlying test wells either actively drilling or in immediate prospect of being drilled.