This award provides one-half of the funding required to purchase a multicollector, stable isotope mass spectrometer with micro-sampling capabilities to be installed and operated in the Department of Geology at the University of California-Davis. The University is committed to providing the remaining half of the funds necessary for the purchase and will house and maintain the equipment. The new instrument will establish the first campus-wide, multi-purpose stable isotope facility at UC-Davis where three Principal Investigators will constitute the prime-user group with research projects on fluid-rock interactions in submarine and subaerial hydrothermal geochemistry and interpreting the paleoclimatic record of deep-sea core samples.