The Mississippian Antler basin is a well known but poorly understood sedimentary system. It has been called a foreland, but the geometry and timning of the orogeny that formed the basin have been the subject of diverse speculation. Preliminary work has revealed new stratigraphic detail and several features that are anomalous for a foreland: synorogenic deformation is mild and poorly preserved, deformation took place as several discrete events that caused uplift, the basin was wide and shallow, the foreland was long-lived but the sedimentary section is not thick, and the sedimentary sequences are mostly transgressive. Current foreland basin models are defined by the type of associated orogency, and basin stratigraphy reflects ongoing tectonism. The stratigraphy of the Antler system provides an excellent test of these foreland basin models, because it differs from most foreland systems described to date. This project will emphasize detailed sedimentology of newly recognized stratigraphic sequences, mapping of sedimentary facies, and analysis of synorogenic deformation. The results will be applied to existing models of foreland evolution in order to expand foreland basin models.