9506392 Farley While the last decade has seen steady advances in measurement techniques and interpretation of the major volatiles (H2O, CO2) and the noble gases (He-Ne-Ar-Kr-Xe) in mantle-derived materials, simultaneous investigation of both sets of tracers has rarely been undertaken. These species have similar yet systematically distinct geochemical affinities, and characterization of the interrelationships among them can provide unique new insights to both magmatic phenomena and to the origin of the chemical heterogeneity of the mantle. This is a project to investigate the relationships among the elemental and isotopic abundances of volatile species in basalt glasses and mafic phenocrysts from several representative localities including spreading ridges and ocean islands. Simultaneous determination of these species will require development and exploitation of tools which are new to this branch of geochemistry, including laser extraction, spectroscopic determination of volatile abundances, and fully-automated gas-handling.
