94-02159 Farley In this project the PIs will participate in the EDISON cruise (Germany, Canada, US, and Australian participants; Crusie ship- Sonne (German) to investigate structure, petrology, tectonics of the young alkaline volcanic centers (TLTF) in the southwestern Pacific. An intriguing aspect of this study is the presence of mantle wedge xenoliths in some of the alkaline basalts. These xenoliths are sulfate and carbonate-rich (metasomatized). Another intriguing aspect is the 1982 discovery of a gold deposit in Lihir island. The authors argue that "this is probably the best known locality in the world" in which to investigate the interrelation- ship between extensional tectonics in a convergent margin, arc magmatism, mantle metasomatism, and gold-copper mineralization. This is what the team will do. Ship time and other expenses at sea will be borne by the Germans; the PIs are only requesting funds for pre-cruise expenses and post-cruise research.