ABSTRACT

Late Pleistocene depositional and morphostratigraphic units designated in Mississippi, were correlated along the north Gulf between Texas and northwest Florida. Subsidence resulted in thick Pleistocene sequences in the north-northwest. Due to steady, inland-centered uplift, only a thin Late Pleistocene interval survived erosion on the northeast Gulf. Neogene siliciclastics define the base of the Pleistocene. The open marine-to-paralic Biloxi, alluvial Prairie, and Gulfport barrier formations were deposited during the Sangamonian Interglacial. In sharp contrast with the Atlantic south coast, only a single barrier shoreline is recognized. Two sets of paralic deposits, separated by weathering horizon and/or different consolidation state indicate Sangamonian shoreline fluctuations on the Texas coast. Evidence contradicts recent suggestions of coastwise surface aggradation and of a warm interval, associated with a major eustatic rise during Middle/Late Wisconsinan times.