9871423 Ripperdan This grant, supported equally by Experimental Program to Stimulate Competitive Research (EPSCoR) and the Major Research Instrumentation (MRI) Program, provide partial funding for the acquisition of a gas source stable isotope ratio mass spectrometer (SIRMS) for the Geology Department at the University of Puerto Rico, Mayaguez. Establishment of this SIRMS facility at Puerto Rico will make it the only one of its kind both on the island and within the greater Caribbean region. As a result, acquisition of a SIRMS by the University of Puerto Rico provides an infrastructural improvement for the commonwealth and the University that significantly increases the ability of the PI and UPR colleagues to compete for federal and private sector research and development funding. While the main users of this facility are relatively young, they have already begun a number of research projects that require stable isotopic analyses of carbon and oxygen in marine microfossil tests, coralline skeletons, dissolved organic and inorganic carbon in groundwater and biological samples. Specific studies that will make use of the SIRMS include: combined chemostratigraphic and paleontological studies of the late Ordovician marine mass extinction, research on millennial-scale stable isotopic proxies of sea surface temperatures as recorded in coral skeletons, isotopic studies of adsorbed and structural water within natural and artificial zeolites in order to appraise their effectiveness for use in environmental remediation efforts and to improve their design, isotopic studies of hair for use in forensic toxicology, and ecological studies of the fate and pathways of organic matter in tropical ecosystems. Finally, given the number of currently funded NSF researchers that continue to conduct stable isotopic investigation on Caribbean samples, be they aqueous, coralline, igneous or otherwise, this facility will undoubtedly find use by a large number of visiting scientists and their students from U.S. mainland institutions. ***
