A series of 12 tectonic and lithofacies maps representing critical periods of the evolution of the Appalachian-Ouachita orogen were compiled from published sources and interpretation of seismic and subsurface data. The distribution of sediments supports the concept of multiple deformation that resulted from the collision and accretion of small plates or irregular margins of larger plates with North America.

During the Eocambrian and Early Cambrian, a series of rifts developed within the craton subparallel to the continental margin of the Iapetus Ocean. Ouachita sediments were deposited in this rift zone along the southern margin of the craton. However, the rift zone did not persist in the Appalachians, and the sediments in that belt were deposited along the continental margin.

In the Middle Ordovician, the extensional regime continued in the Ouachita belt while compression associated with plate collision began in the Appalachians. The northwest-southeast-trending boundary between these areas persisted throughout the evolution of the orogens. The sedimentary records indicate that the initial compressional deformation in the Ouachita belt began during the Late Mississippian, and the final phase of deformation in the Appalachians was initiated slightly later, during the Early Pennsylvanian.

Structural features associated with thrusting basin sediments over foreland areas were controlled to a great extent by the presence or absence of buttresses. The Ouachita Mountains area provides the best illustration of contrasting structural styles along the thrust belt. Elsewhere along the thrust belts the evidence is either covered by younger sediments or altered by a complex tectonic history.

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