This award provides partial funding for the acquisition of a secondary ion mass spectrometer (SIMS or ion microprobe) that will be installed and operated in the Geology Department at Arizona State University. Arizona State University and the National Aeronautics and Space Agency are committed to providing the remaining funds necessary for the acquisition. The instrument is capable of precise in situ quantitative analysis of trace elements and rare isotopes in natural solid samples, with spatial resolution of approximately ten microns. The new ion microprobe will be devoted mainly to research and graduate-level teaching in a range of investigations dealing with the early history of the solar system, planetary atmospheres, the origin of life on earth and, possibly, other planets, the origin of terrestrial magmas, and the role of aqueous fluids in environmental geochemistry and diagenesis. ***