The Marietta basin is in southern Oklahoma between the Muenster arch on the southwest and the Criner Hills uplift on the northeast; it extends from Love County, Oklahoma, southeastward through Cooke and Grayson Counties, Texas, the deepest part being known as the Gordonville trough.

The folded and faulted buried ridge (mid-basin ridge) on which the Southeast Marietta field is located has a more southward strike than the present basin axis, and divides the basin into two parts. The thickest sections of Atoka and older sediments were deposited north of the ridge.

The Gordonville trough developed in Late Mississippian

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or Early Pennsylvanian time from a gentle downwarp into a deep, relatively narrow trough with steep, commonly faulted sides, growing progressively as it received up to 5,000 feet or more of sediments of Atoka, Morrow, and possibly Springer (Goddard?) ages.

The Atoka and Morrow boundaries are indefinite on the basis of present knowledge. Some geologists place the top of the Atoka at the base of the Davis Sand (Grayson County, Texas). The writer has placed the top at an oolitic limestone (Lester?) midway between the Baker and Davis Sands. Westheimer believes the "micaceous sand" in the Ardmore basin Dornick Hills correlates with the micaceous Hartshorne Sandstone of the Arkoma basin and the Davis Sand of Grayson County. The sandstone correlated as Davis or "micaceous" in the Southeast Marietta field is several hundred feet higher stratigraphically than the Davis Sand of Grayson County.

A thick section of pre-Atokan appears northward as well as eastward from the mid-basin ridge. This is believed to be mostly Morrowan-lower Dornick Hills, Springer (Goddard?), and Caney. The boundaries are indefinite and based on electric-log characteristics, related to early sample work. More qualified determinations are necessary in samples from later wells.

Post-Atokan Dornick Hills also thickens eastward and northward in Grayson County, but thins and disappears southwestward against the lower faulted margin of the Muenster uplift. The same components may be noted in the Des Moines or Strawn (Deese), although the thickening here may be more related to the development of the present Gordonville trough by foundering and filling during erosional destruction of the Ouachitas.

More intense folding and thrust faulting, even deep within the basin, complicate considerably the development of structure and stratigraphy because of the loss of section (a loss which is not the result of depositional factors).

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