Exploratory drilling decreased 7.5% in Oklahoma during 1961 compared with the previous year. A success of 29.2% was realized. Fifty new-field wildcats were discovery wells from a total of 242 new-field wells drilled for a 20.7% success. Significant new-field discoveries were made in the Anadarko and Arkoma basins again in 1961. Improved geological and geophysical interpretations along with more critical reviews of exploratory drilling budgets by industry managements are reflected in the continuing high success ratios. Successful wildcat ventures encouraged several lease plays, particularly in the deeper parts of the Anadarko basin. Additional leasing around discover wells was done throughout Oklahoma. More than 70% of the state is currently under lease. Oil production for the year was up slightly compared with 1960. Gas production increased also over 1960 production. Secondary recovery accounted for 39.7% of the total crude oil production in the state. Seismic activity increased 13.8% compared with the previous year.