THIS PROJECT ADDRESSES THE PROCESSES CONTROLLING CHEMICAL ALTERATION AT COLD-BASED GLACIERS ON VOLCANIC MARS-ANALOG BEDROCK. TERRESTRIAL WET-BASED GLACIERS ARE NOW UNDERSTOOD TO CHEMICALLY ALTER THEIR BEDS AND FORELANDS HOWEVER COLD-BASED GLACIAL CHEMICAL ALTERATION IS A POORLY UNDERSTOOD PROCESS BUT ONE WHICH IS VITAL TO UNDERSTAND IN ORDER TO UNDERSTAND PAST AND PRESENT CHEMICAL ALTERATION ON THE SURFACE OF MARS. MARS IS KNOWN TO HAVE A LONG-LIVED AND EXTENSIVE CRYOSPHERE. THE SURFACE OF MARS SHOULD THUS SHOW WIDESPREAD EVIDENCE FOR GLACIAL CHEMICAL ALTERATION. HOWEVER PAST AND PRESENT-DAY MARS GLACIERS ARE THOUGHT TO BE COLD-BASED. COLD BASED GLACIERS IN WHICH THE ICE IS FROZEN TO THE UNDERLYING BEDROCK ARE FOUND AT HIGH LATITUDES AND HIGH ELEVATIONS ON EARTH AND ARE THUS UNDERSTUDIED DUE TO THEIR REMOTE AND INACCESSIBLE LOCATIONS. COLD-BASED CHEMICAL ALTERATION PROCESSES ARE PARTICULARLY NOT WELL UNDERSTOOD. THIS WORK WILL INVESTIGATE CHEMICAL ALTERATION AT COLD-BASED GLACIERS THROUGH A COMBINATION OF REMOTE SENSING FIELD OBSERVATIONS AND LABORATORY ANALYSES OF WATER ROCKS AND SEDIMENTS. WE WILL CONDUCT A FIELD CAMPAIGN AT THE RAPIDLY RETREATING HIGH-ALTITUDE COLD BASED GLACIERS ON THE SUMMIT OF KILIMANJARO VOLCANO TANZANIA (WITH BEDROCK COMPOSITIONS ANALOGOUS TO MARS) AND COLLECT BOTH IN SITU SPECTRA AND SAMPLES FOR LAB ANALYSES. ORBITAL IMAGE ANALYSIS ALLOWS DIRECT MEASUREMENT OF THE ALTERED TERRAIN AT THESE LOCATIONS BUT DIRECT MEASUREMENT OF IN SITU SPECTRA SAMPLE COLLECTION AND OTHER LABORATORY ANALYSES ARE REQUIRED TO TIE SPECIFIC GEOLOGIC PROCESSES TO REMOTELY SENSED MEASUREMENTS AT REGIONAL SCALES. LABORATORY ANALYSES OF RETURNED SAMPLES WILL ALLOW US TO DETER-MINE THE MINERALOGY AND GEOCHEMISTRY OF WEATHERED VOLCANIC MATERIALS AND PROVIDE SIGNIFICANT INSIGHT INTO THE PROCESS OF COLD-BASED GLACIAL ALTERATION. THE RESULTING HIGH SPATIAL RESOLUTION DATA WILL BE SCALED TO ORBITAL RESOLUTIONS AND COMPARED TO ORBITAL SPECTRAL SIGNATURES WITH SIMILAR RESOLUTIONS TO MARS ORBITAL DATA. MARS SCIENCE LABORATORY-RELEVANT ANALYSES WILL ALSO BE MADE IN ORDER TO BETTER UNDERSTAND RESULTS FROM THAT MISSION. OUR RESULTS WILL IMPROVE OUR UNDERSTANDING OF HOW THESE UNIQUE GLACIERS ALTER THEIR UNDERLYING TERRAIN AND ALLOW A BETTER UNDERSTANDING OF WEATHERING PROCESSES ON PAST AND PRESENT-DAY MARS. THE PROPOSED RESEARCH IS DIRECTLY RELEVANT TO THE SOLAR SYSTEM WORKINGS PROGRAM BECAUSE WE WILL PERFORM LABORATORY STUDIES THAT EXAMINE PHYSICAL OR CHEMICAL PROPERTIES AND PROCESSES THAT HAVE OCCURRED ON THE SURFACE OF MARS AND FIELD STUDIES OF TERRESTRIAL ANALOGS OF PLANETARY ENVIRONMENTS. IN PARTICULAR THE PROPOSED LABORATORY STUDIES DIRECTLY ADDRESS THE CALL TO HELP UNDERSTAND THE EVOLUTION AND MODIFICATION OF SURFACES WITHIN OUR SOLAR SYSTEM BY CHARACTERIZING AND UNDERSTANDING THE CHEMICAL AND MINERALOGICAL FEATURES OF POTENTIAL GLACIAL ALTERATION PHASES ON THE MARTIAN SURFACE.