A FUNDAMENTAL GOAL IN PLANETARY SCIENCE IS TO UNDERSTAND THE EARLY HISTORY OF THE SOLAR SYSTEM. EFFECTIVE WAYS IN WHICH THIS CAN BE INVESTIGATED INCLUDE THE PETROLOGIC INVESTIGATION OF PRIMITIVE METEORITES; EXPERIMENTS THAT REPRODUCE PROCESSES THAT MAY HAVE OCCURRED IN THE EARLYSOLAR SYSTEM; AND ISOTOPIC ANALYSES OF PRIMITIVE SAMPLES. ALL THREE OF THESE AVENUES OF INQUIRY ARE PURSUED IN THIS PROPOSED STUDY. OVER THE PAST DECADE A LARGE SUITE (OVER 200 SPECIMENS) OF VERY LOW-GRADE CARBONACEOUS CHONDRITES CLASSIFIED AS CO3S HAS BEEN RETURNED FROM ANTARCTICA MAINLY FROM THE MILLER RANGE AND THE DOMINION RANGE. SUCH SAMPLES ARE OF GREAT INTEREST BECAUSE THEY HAVE RELATIVELY HIGH CONTENTS OF PRESOLAR SILICATES (E.G. ALEXANDER ET AL. 2014) BUT THEY ARE ALSO IMPORTANT BECAUSE THEYPROVIDE AN OPPORTUNITY TO STUDY CHONDRULES AND REFRACTORY INCLUSIONS THAT DO NOT HAVE METAMORPHIC OVERPRINTS FROM THEIR PARENT BODIES. WE HAVE BEGUN A PETROLOGIC STUDY OF THE REFRACTORY INCLUSIONS IN SUCH SAMPLES (SIMON AND GROSSMAN 2014; 2015) AND IN TASK 1A WE PROPOSE TO CONTINUE AND EXPAND UPON THAT WORK. IN ADDITION IN A MULTIDISCIPLINARY (MIN-PET/TEM/XANES) STUDY OF LOWGRADECARBONACEOUS AND ORDINARY CHONDRITES TASK 1B WE WILL INVESTIGATE THE EFFECTS OF THE ONSET OF METAMORPHISM ON CHONDRITE PARENT BODIES. THE DISCOVERY OF TRIVALENT TI IN OLIVINE AND PYROXENE IN SEMARKONA CHONDRULES (SIMON ET AL. 2008) INSPIRED AN EXPERIMENTAL STUDY OF THE REDOX KINETICS OF FE AND TI IN CHONDRULE-LIKE SYSTEMS IN WHICH WE BEGAN TO EVALUATE THE RELATIVE RATES OF OXIDATION OF THESE ELEMENTS. PRELIMINARY RESULTS WERE REPORTED BY S. SIMON ET AL. (2011; 2014) AND A SECOND GENERATION OF THESE CHALLENGING EXPERIMENTS TASK 2 IS PROPOSED. OTHER MAJOR TOOLS FOR INVESTIGATION OF EARLY SOLAR SYSTEM PROCESSES ARE APPLICATION OF ISOTOPIC CHRONOMETERS TO CHONDRULES AND INCLUSIONS FOR BOTH RELATIVE AND ABSOLUTE DATING (TASKS 3A AND 3B; AND THE MEASUREMENT OF STABLE ISOTOPIC COMPOSITIONS FOR BOTH IDENTIFICATION OF RESERVOIRS AND EVALUATION OF MASS FRACTIONATION (EVAPORATION) EFFECTS IN RIMS ON REFRACTORY INCLUSIONS (TASK 3C). IN SUCH STUDIES SELECTION OF APPROPRIATE SAMPLES AND DETAILED CHARACTERIZATION OF THEM ARE NECESSARY FOR OBTAINING THE MOST MEANINGFUL RESULTS POSSIBLE. THE PROPOSED WORK WILL INVESTIGATE: THE ORIGINS OF SOME OF THE EARLIEST SOLAR SYSTEM MATERIALS (CHONDRULES AND REFRACTORY INCLUSIONS); PROCESSES THAT OCCURRED DURING CHONDRULE FORMATION; EFFECTS OF THE FIRST STAGES OF CHONDRITE METAMORPHISM; ABSOLUTE AND RELATIVE AGES OF CHONDRULES; AND THE DISTRIBUTION OF 26AL AND 16O RESERVOIRS IN THE EARLY SOLAR SYSTEM AND AS SUCH IS HIGHLY RELEVANT TO THE GOALS OF THE EMERGING WORLDS PROGRAM.