9406120 Frey This award provides partial funding for the support of a technician assigned to the operation and maintenance of the Neutron Activation Analysis Laboratory in the Department of Earth, Atmospheric, and Planetary Sciences at the Massachusetts Institute of Technology. The laboratory is a facility dedicated to the analysis of natural materials, principally terrestrial rocks and minerals. Gamma ray spectroscopy is used to determined the abundance of many trace elements, used as tracers to better understand the processes which have formed the Earth's crust and mantle. The instrumentation of the facility consists of semi- conductor detectors, multichannel analyzers, and computer control. The facility is used for sponsored geochemical research of the Principal Investigator and colleagues at MIT and by a diverse group of other U.S. scientists, including faculty and students from other universities and colleges, principally in the northeast. *** 9406684 Johnson This award provides partial funding for the support of a technician assigned to the Radiogenic Isotope Laboratory in the Department of Geology and Geophysics at the University of Wisconsin, Madison. The technician will assist in the operation and maintenance of the laboratory's equipment that includes a multicollector thermal ionization mass spectrometer and associated instrumentation for sample preparation and data analysis. The laboratory is a resource for mass spectrometric analysis needed in research and teaching projects in the earth sciences by a large number of researchers on-campus and off-campus. Research applications include work on Arctic Ocean sediments, mantle geochemistry, volcanism, geochronology of carbonates in the Michigan Basin and Wisconsin Arch provinces, and Archean and Proterozoic granites. The technician will also participate in the technical developmental work of the laboratory, including the development of new methods for the quantitative measurement of the iso topes of hafnium. ***
