Although fewer outstanding discoveries were made in undeveloped regions of Oklahoma during 1948, substantial reserves were added by wildcat discoveries and extensions especially on the southwest flank and in the southeastern embayment of the Anadarko basin, the Ardmore basin, the Seminole area, and in east-central Oklahoma.

The outstanding development in Oklahoma during 1948, from a regional exploration point of view, was the continued success of exploratory drilling in the Elk City area, on the southwest flank of the Anadarko basin, which emphasized the geologic significance of "granite wash" production in Oklahoma. Discoveries in this area resulted in further leasing and exploration in the entire southwest Anadarko basin extending from Oklahoma into the Texas Panhandle.

Production of oil increased to 155,578,453 barrels, representing an increase of 9.9 per cent over the 1947 production. Total reserves of crude oil increased by 31 per cent. Production of marketed natural gas increased to 276,542,084,000 cubic feet and casinghead gas to 178,751,567,000 cubic feet, or 12 per cent over the gas marketed in 1947. Total reserves of natural gas were estimated to be practically the same at 11,332,445 million cubic feet at the end of 1948. In number of holes drilled Oklahoma ranked second with a total of 3,827, of which 713 were wildcats resulting in 94 new discoveries.

The deepest producing well in Oklahoma, one of the deepest in the world, was completed during 1948 in an Ordovician sandstone zone from 12,855 to 13,611 feet.