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Formational contact and stream channel directional data totaling 5,356 measurements were taken from topographic and geologic maps of coastal Mississippi to determine the relationship of drainage and outcrop patterns to the Wiggins uplift. Data were compared to structural models developed by Moody and Hill in 1956 and by Miller in 1982, and to orientations of faulting and axes of structure. The Rayleigh test for uniformity reveals that neither orientations of drainage channels nor orientations of the trace of the unconformable contact between the Pascagoula and Citronelle formations exhibit a random distribution.
The effects of structure on the outcrop pattern can be seen by (1) the mean orientation of formational contact, which is nearly coincident with part of a wrench fault structural model, and (2) the greater areal extent of Tertiary outcrops in this region than in comparable regions of Louisiana Alabama. The predominant orientations of drainage channels exhibit: (1) a greater degree of coincidence with the predominant orientations of formational contacts than with any other single factor; (2) a significant coincidence with the axis of the Wiggins uplift; (3) a directional relationship to the structural axes that conforms to the relationship of wrench structures predicted in the structural models; and (4) poor alignment with the faulting described by Fisk in 1944 which are thought to also be wrench structures. It is suggested that anomalies in the courses of Red Creek, Black Creek, and the Pascagoula River are related to the Wiggins uplift and other associated wrench structures, and further, that structures described by Fisk in 1944 are locally deformed by the Wiggins uplift.
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