This award will enable the PI and his collegues to complete several remaining tasks in their continuing study of the geochemistry of island-arc processes. By using isotopic, trace element and U-series nuclides they have documented relavent processes - assimilation, fractional crystallization, etc., - at Paricutin volcano in Mexico, the Tabar-Feni islands in the Western Pacific, the Carpathians, and in the Aegean arc. During the remaining two years they will concentrate on finishing the Carpathian and Aegean projects. A small effort will be devoted to further analyses of trace elements in mantle lherzolites, and the writing up of the Paricutin and Tabar-Feni work will be completed.
