In January of 1985, a densely-recorded, wide-aperture seismic experiment was performed by the University of Texas at El Paso and at Dallas, across the southwestern Oklahoma aulacogen. A two-dimensional P-wave velocity distribution is estimated for the Wichita uplift, the Anadarko basin, and the interface between them, by iterative tomographic imaging of travel-time picks from seven shots located near the 100-km-long recording line. The region that is imaged is roughly triangular in shape, with depth = 0 km at the ends of line and ≈ 15 km near its center. The main features that are revealed are a high-velocity (>6.8 km/sec) central core in the Wichita uplift and an asymmetrical Anadarko basin with decreasing velocities toward the basin axis. There are indications, within the uplift, of local high-velocity sills and a local low-velocity region that may be a remnant of normal crustal material.