Diachronous Thrust Loading and Fault Partitioning of the Black Warrior Foreland Basin within the Alabama Recess of the Late Paleozoic Appalachian—Ouachita Thrust Belt
William A. Thomas, 1995. "Diachronous Thrust Loading and Fault Partitioning of the Black Warrior Foreland Basin within the Alabama Recess of the Late Paleozoic Appalachian—Ouachita Thrust Belt", Stratigraphic Evolution of Foreland Basins, Steven L. Dorobek, Gerald M. Ross
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The triangular outline of the late Paleozoic Black Warrior foreland basin on the southern edge of the North American craton in Alabama and Mississippi is framed on the southwest by the northwest-striking Ouachita thrust front and on the southeast by northeast-striking Appalachian thrust-belt structures. The nearly orthogonal intersection of the Ouachita and Appalachian thrust belts implies a composite history of flexural subsidence of the foreland. A long homocline that dips southwest beneath the Ouachita thrust front defines the structure of the basin, and a southwestward-thickening, northeastward-prograding synorogenic clastic wedge of Mississippian and Pennsylvanian rocks fills the basin, indicating a thrust load and sediment source (Ouachita thrust belt) on the southwest. A synorogenic clastic wedge in the Appalachian thrust belt (Cahaba synclinorium) is similar in provenance and dispersal to that in the Black Warrior basin, indicating that the palinspastic site of Appalachian thrust sheets was also part of the original Ouachita foreland. Greater thickness of the clastic wedge in the Cahaba synclinorium reflects partitioning of the Ouachita foreland by reactivation of the down-to-southeast Birmingham basement fault system. Addition of northwest-prograding clastic sediment during the Early Pennsylvanian records initiation of Appalachian orogenesis on the southeast. Subsequently, the southeastern part of the southwest-dipping Black Warrior foreland basin was displaced by northwest-propagating Appalachian thrusts, and part of the older, northeastward-prograding, Ouachita-derived clastic wedge was imbricated.