Exploitation of existing fields and discoveries remained the focus in 1989 with development wells outnumbering exploration wells 15 to 1. Exploration drilling dropped 14.8%, whereas development drilling increased 3.3%. The success rate for exploratory wells increased from 27.5% to 30.8%, and the success rate for development wells increased from 69.8% to 70.3%.

The most actively explored area was the Arkoma basin with 41 exploratory wells. The search for Arbuckle reservoirs continued to expand as operators completed successful Arbuckle discoveries in the Arkoma basin, Anadarko basin, Ardmore-Marietta basin, and the Sedgwick shelf. In 2 of the last frontier basins in the Mid-Continent (the Palo Duro basin and the Hardeman basin), operators completed 6 new-field wildcats.

Elsewhere in Oklahoma, the dominant plays were the Morrow-Springer in the Anadarko; the Viola, Hunton, and Wilcox along the Pauls Valley uplift; and the Pennsylvanian along the Nemaha uplift and the Cherokee shelf. Consolidation and sales of assets continued with a new variation involving asset exchanges rather than sales.