9509641 Harrison This grant provides funds for operations and maintenance support of the CAMECA ims-1270 high transmission, high resolution ion microprobe at UCLA as a world class microanalysis facility. This is the first instrument of its kind in the U.S. and in the generation of new instruments designed to analyze the isotopic and elemental composition of terrestrial and planetary materials at the micro-scale and has great potential to provide major advances in our understanding of geochemical processes. Support will be in the amount of $600,000 over a three year period and follows a two year grant which supported the initial commissioning of this instrument and the development of measurement routines for U-Th-Pb analyses of zircon and monzanite. It is expected that a significant user-base will be established for these analyses by the end of this three-year period. Development of measurement techniques for the oxygen isotopic composition in electrically insulating samples and Thorium isotope systematics will continue and hopefully become available to the isotope geochemical community. ***
