The Wilburton-Ouachita Trend--A Gas Giant for the 1990s

Abstract

The Wilburton-Ouachita trend of southeastern Oklahoma runs roughly northeast-southwest from the town of Atoka near the Texas line to the town of Poteau and the Arkansas line. This 120-mi trend is a narrow system 25-35 mi wide with a strong horst-graben structure that separates the Arkoma basin in the north from the Ouachita basin hidden under the thrust system to the south. Recent seismic shooting shows that the basin was downwarped during the rift period of the Acadian orogeny. A fracture system of normal faults was formed in these lower Paleozoic carbonates. These faults were rejuvenated during the Morrow-Springer deposition, and subsequent Wichitan tensional faulting caused many of the horst blocks to move thousands of feet upward. During Atokan time massive shales were deposited into this faulted basin, causing differential loading and more movement. The final period of movement came in Late Pennsylvanian time with the compressional forces of the suturing of the South Oklahoma aulocogen and the thrusting of the Ouachita plate over the deformable Pennsylvanian shales. The author will examine how these forces formed the productive structures that are being drilled today in the Arkoma basin. A series of seismic lines crossing the Wilburton-Ouachita trend will be shownmore » along the extent of the play from Poteau to Atoka.« less