Contractional, basement-involved foreland deformation in the Rocky Mountains of the conterminous United States occurred during the latest Cretaceous to Paleogene Laramide orogeny. Current kinematic hypotheses for the Laramide orogeny include single-stage NE- to E-directed shortening, sequential multidirectional shortening, and transpressive deformation partitioned between NW-striking thrust and N-striking strike-slip faults. In part due to this kinematic uncertainty, the links between Laramide deformation and plate-margin processes are unresolved, and proposed driving forces range from external stresses paralleling plate convergence to internal stresses due to gravitational collapse of the Cordilleran thrust belt.

To determine the tectonic controls on Laramide deformation, kinematic data from...