9601783 Frost This grant, made through the Academic Research Infrastructure (ARI) Program, provides $250,000 as one-half support of the costs of acquiring a thermal ionization mass spectrometer (TIMS) with ion counting capabilities for use in isotopic studies of igneous petrogenesis, thermochronology and geochronology for tectonic studies, and environmental isotope geochemistry at the University of Wyoming. The instrument will replace a somewhat antiquated VG TIMS purchased in 1984 but more recently upgraded in 1989. However, since the upgrade, the instrument has been plagued with technical problems that have only more recently (1993) been rectified and data produced. The 50% match from the University of Wyoming is part of a one-time, $18M state supported Geology building expansion/improvement. Specific studies that will utilize the capabilities of this new TIMS will include research on the petrogenesis of the Laramie Anorthosite Complex and Aleutian and Caribbean arc magmas through examination of Pb, Sr and Nd isotopic signatures, the tectonic evolution of the Western U.S. based on thermochronologic and geochronologic techniques and Sr and Nd isotopic studies of groundwater hydrology and weathering processes. ***
