This award will provide partial support for two years of operations and maintenance of the University of New Mexico/Sandia National Laboratory ion microprobe facility. A used, but relatively modern, ion microprobe instrument has recently been moved from Sandia to the Department of Earth and Planetary Sciences at the University of New Mexico. It is to be operated jointly by University and Sandia staff, and the available machine analytical time will be split evenly between the two collaborating organizations. The analytical capabilities of the instrument include in situ measurements of trace elements and isotopic compositions with spatial resolution on the order of ten microns, and it will be used in a broad variety of geochemical research projects by investigators from the University of New Mexico as well as off-campus users.