THIS PROPOSAL PRESENTS FOUR NEW SCIENCE TASKS FOR OUR RESEARCH TEAM: 1) A STUDY OF VALENCE STATE PARTITIONING OF EU CR AND V BETWEEN PYROXENE AND A MARTIAN BASALT AS AFUNCTION OF OXYGEN FUGACITY (IW-1 TO FMQ) AND CRYSTALLIZATION HISTORY 2) A COMPARATIVE PLANETARY MINERALOGY STUDY OF SULFIDES IN BASALTS TO GAIN A BETTER UNDERSTANDING OF CHALCOPHILE ELEMENT BEHAVIOR IN DIFFERENT PLANETARY ENVIRONMENTS 3) A RECONSTRUCTION OF THE PETROGENETIC HISTORY OF OLIVINE MEGACRYSTS IN MARTIAN BASALTS TO GAIN INSIGHTS INTO THE PETROGENESIS OF "DEPLETED" AND "ENRICHED" SHERGOTTITES AND 4) COMBINED SIMS-TIMS STUDIES OF MARTIAN AND LUNAR METEORITES TO GAIN ADDITIONAL INSIGHTS INTO THE ORIGIN AND EVOLUTION OF PLANETARY MANTLES AND THE GENERATION AND HISTORY OF BASALTS FROM THESE TWO PLANETS. OUR DIVERSE RESEARCH BACKGROUNDS IN CRYSTAL CHEMISTRY MINERALOGY PETROLOGY AND GEOCHEMISTRY PROVIDE A STRONG FOUNDATION TO USE AN INTEGRATED APPROACH TO SOLAR SYSTEM PROBLEMS. THIS BACKGROUND COMBINED WITH EXPERIMENTAL PETROLOGY LABORATORIES (UNM AND JSC WITH INDIVIDUAL AND INDIVIDUAL) ELECTRON MICROPROBE (EMP UNM) SECONDARY ION MASS SPECTROMETRY (SIMS UNM) NANO-SIMS (CALTECH WITH INDIVIDUAL) TRANSMISSION ELECTRON MICROSCOPY (TEM UNM) THERMAL IONIZATION MASS SPECTROMETRY (TIMS LLNL WITH INDIVIDUAL) FOCUSED ION BEAM MICROSCOPY (FIB UNM) SYNCHROTRON MICROXANES AND SYNCHROTRON X-RAY FLUORESCENCE (XANES AND SXRF RESPEVTIVELY NATIONAL SYNCHROTRON LIGHT SOURCE AT ARGONNE NATIONAL LABORATORY WITHINDIVIDUAL) ENABLES US TO USE INNOVATIVE APPROACHES TO THE STUDY OF SOLAR SYSTEM MATERIALS. THE TASKS OUTLINED IN THIS PROPOSAL HAVE HIGH RELEVANCE TO THE COSMOCHEMISTRY PROGRAM AND NASA'S GOALS FOR THE EXPLORATION OF THE SOLAR SYSTEM. FULFILLING THESE TASKS WILL PROVIDE INSIGHTS INTO THE ORIGIN OF TERRESTRIAL PLANETS AND PROCESSES INFLUENTIAL IN THEIR EVOLUTION. FURTHER THESE PROPOSED STUDIES ARE RELEVANT TO THE GOALS IDENTIFIED BY THE NRC NAC LEAG AND MEPAG FOR THE EXPLORATION OF THE MOON AND MARS.