9526702 Grove This award is a component of an international, multi-institutional, interdisciplinary study of the Kaapvaal craton in southern Africa. This four-year project will determine the geological processes that led to the formation and stabilization of this and other ancient continental cratons. The Kaapvaal craton preserves Archean (2.6 to 3.6 Ga) continental crust and mantle. The crustal rocks are well exposed and the mantle and deep crust have been sampled by abundant kimberlites that provide information about the spatial distribution and temporal evolution of deep lithospheric structure. The Principal Investigators will use a number of geophysical and geochemical techniques to investigate the structure of the craton. The results of these diverse approaches will be integrated with research programs of several South African groups to provide a comprehensive understanding of three-dimensional structure, chemical composition and tectonic evolution of the mantle and crust of the Kaapvaal craton. The data will be used to evaluate competing models of craton assembly and to provide constraints on the continental dynamics of the early Earth. ***