Correlation of Permo-Triassic redbeds in the Williston basin is relatively easy when a normal section is present; however, when some of the section is missing because of truncation or salt solution, correlation becomes very difficult, especially where redbeds of Triassic age rest on similar beds of Permian age or older. Poor samples and inadequate mechanical logs within the redbed section make correlation even more difficult. Correlation with the outcrop in the Black Hills is complicated further by the presence of massive salt beds in the subsurface that are not present on the surface.

Salt solution is common and, where faulting and fracturing are known to exist, appears to be related to paleostructures. Failure to recognize this phenomenon could result in misinterpretation of structure, especially when the seismic method is used.

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