The dynamics of motion of the South American plate

Investigates the driving and resistive plate tectonic forces acting on the South American plate in order to establish a detailed basis for future stress modelling. Incorporating the forces which are expected to be of major importance, a first-order model is defined. Solutions are obtained using four different determinations of the Euler vector of absolute motion of the South American plate, which is taken to define the orientation of the basal shear stress. The results demonstrate that the concept of a basal shear stress actively driving plate motion cannot be discarded on the basis of a dynamical analysis. Further, with the assumption that basal drag is entirely concentrated below the continental part of the lithosphere, estimates of the maximum amount of continental basal shear resistance are derived. -from Authors