9504941 Michael Water is a minor constituent of the Earth's mantle but it has a strong effect on the melting of the mantle. Cl is a trace component in basalts but it appears to be added to magmas when they are contaminated with old basalts that have been weathered or by sediment. Water and Cl have been measured previously in oceanic basalts by Michael, and he now wants to analyze basalts from the submerged parts of oceanic platforms that were formed by the eruption above mantle hotspots. This will be done to determine if water is higher in hotspots as might be expected from the excessive melting at hotspots, and to determine if Cl is elevated in these basalts to determine if the basalts have assimilated ocean crust or sediments. These results will be important for understanding the evolution and processes in the Earth's mantle. ***