This project will involve detailed geochemical and isotopic (He, Pb, Sr, Nd, and O) study of Holocene-to-recent hot spot generated lavas on Canary and Galapagos islands. The principal goal is to obtain constraints on scale of heterogeneity associated with hot spot volcanism and to decipher the origin of seamounts and oceanic plateaus. The P.I. will also explore the potential of ?U+Th!/He dating of young lavas.