EAR-9525336 Stern, Libby A. The oxygen and hydrogen isotope systematics of non-carbonate minerals in altitudinal transects will be compared with oxygen isotope values of cogenetic calcite and meteoric water. These data will: (1) quantify the isotopic effects of soil water evaporation, and (2) test which soil minerals are more useful as climate indicators. The assumption behind the method is that soil minerals record the isotopic composition of meteoric water at the time of their formation. The oxygen isotope value of pedogenic calcite has been used as a proxy for climate, but the climate record preserved in other soil minerals is largely unexplored. Because calcite does not form in soils in relatively humid climates, this work, if successful, will greatly expand the environments in which climatic indicators can be utilized.