This award will support research planned for a new high precision mass spectrometer dedicated to analyses of Ne and N isotopes in mantle materials. Work will be carried out on the following questions: 1) Are Ne data showing straight-line plots against He ratios correct? 2) Are there similar He and Ne isotopic correlations beside the few already identified, where there appear to be mixtures of plume and MORB material? 3) What is the actual magnitude of Ne20 effects which can be observed? 4) How do xenoliths, diamonds and basalts acquire their characteristic Ne signatures? A variety of additional work will also be carried on, including analyses of He samples from the Hawaiian Volcano chain, Caroline and Marquesas hotspots, Society and Austral Islands, Gambier Islands, Pitcairn, Samoa, and the Indonesian Arc. Finally, work will continue on Ar40/Ar36 ratios in oceanic islands.
