The continental margin off the southeastern United States contains two major basins, the Blake Plateau Basin off Florida and Georgia and the Carolina Trough off South and North Carolina. The Blake Plateau is a large, equidimensional basin that probably is underlain by relatively thick rift-stage crust. It probably was filled dominantly by shallow-water carbonate platform deposits. Reef and carbonate-bank buildups occurred near its seaward edge and the platform deposits interfingered with continental facies deposits near its landward edge. Reef building was interrupted in Barremian time and ended after an Albian-Aptian pulse. Subsequently, deposition did not keep pace with subsidence, and a deep-water plateau was formed. Onset of Gulf Stream flow across the inner Blake Pla eau during the Paleocene prevented seaward progradation of the continental shelf across the plateau, and major deep-water erosion removed the old continental slope, creating a steep cliff, the Blake Escarpment. The Carolina Trough is a long, narrow basin underlain by a narrow zone of rift-stage crust, much thinner than that beneath the Blake Plateau basin. This thin crust, presumably the result of major stretching of continental crust in the rift stage of ocean opening, floated deep isostatically and formed a salt-depositing basin early in continental-margin history. Later sediment loading caused the salt to flow into a series of slope diapirs, and withdrawal of the salt resulted in major subsidence of the block of sediment overlying the trough; movement occurred along growth faults.

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