A recently developed model for thrust belts requires that the thrust wedge deform internally to attain and maintain a critical taper angle during fault development. Although a number of mechanisms are known that would accomplish this, the model has been questioned on the grounds that there is a lack of extensive internal deformation and continuous yielding within thrust belts and that there is evidence that thrusts develop in piggy-back fashion. This study seeks to determine if taper angle-maintaining mechanisms operate in sufficient magnitude to allow the wedge model to function. Fault sequences in both the Rocky Mountains and the southern Appalachians will be studied and sequentially restored from balanced cross-sections and results compared to products predicted from forward modeling with the original section. Results are expected to establish the viability of the wedge model for thrust sheet emplacement.
