Exploratory drilling decreased 10.5% in Oklahoma during 1957 with 19.7% success; development drilling decreased 21.9% with 67.7% success. Significant new-field discoveries include the North Carter of Beckham County, the Southwest Enville of Love County, the Brent of Sequoyah County, and the dual Cromwell and "Wilcox sand" gas discovery in southern Okmulgee County.

Continued emphasis on stratigraphic exploration, coupled with deeper drilling and favorable returns from gas, resulted in active exploration in nearly every section of the state. The widespread exploratory and development interest has led to approximately 55% of the state being under lease. A 20,426 ft. unsuccessful deeper-pool test (No. 170, Fig. 1) drilled in the Cement pool of Caddo County, holds the new depth record for the state.

Seismic activity decreased slightly as compared with previous years. Secondary recovery and production from unallocated or "stripper" oil fields continue to account for more than half the state's oil production.