By Late Pennsylvanian the Arbuckle orogeny was occurring, and represents the last major mountain building event in Oklahoma. The event affected all highland areas in the southern part of the state, and was the principal agent in forming the Arbuckle Mountains. The orogeny also contributed to continual down-warping of the Anadarko and Ardmore basins, allowing for large volumes of sediment shed from the highlands to be deposited.
Due to continual uplift of the region, terrestrial and marginal marine environments were common across south and central Oklahoma during this time. In these environments, ancient rivers transported sediment eroded off the mountains in the south, and deposited them in and on stream channels, flood plans, and lakes across most of northern and north central Oklahoma. Eventually these rivers emptied into a shallow ocean forming deltas, similar to the Mississippi delta of today, as the river empties into the Gulf of Mexico. These deltaic and near-shore deposits are what geologists call marginal marine, and have characteristics of both terrestrial and marine-type deposition.
Going further north and west, the epeiric sea becomes deeper,
and falls less under the influence of clastic sedimentation from highlands
in the south. As a consequence, marine limestones dominate the shallow seas
in the areas of far northern Oklahoma and Kansas.