Four research topics will materially constrain the mineralogy, petrology and geochemistry of the mantle, including source regions and repositories for large-ion-lithophile elements relevant to the modeling of alkali and basaltic magmatism. A focused analytical and interpretive program will be undertaken on ultradeep peridotites, eclogites of ultradeep and shallower origins, regional lithospheric metasomatism, and specific minerals (oxides, diamond, graphite, and zircon). Site selection in the Kaapvaal and West Africa cratons is guided by a body of existing data, sufficient in detail to assure new insights to, and greater definition of the lithosphere, the asthenosphere, and the transition zone. A basic premise and working model will be that kimberlitic clan magmas, melt metasomatism, and the transport of ultradeep diamonds and xenoliths is by plumes that originate at the core-mantle boundary.
