This grant provides partial funding for a 193 nm laser ablation system for use in laser ablation inductively-coupled plasma mass spectrometry (LA-ICP-MS) and (U-Th)/He chronometry at Yale. The laser will increase the versatility of the existing sector ICP-MS and the inorganic geochemistry program at Yale, allowing in situ, spatially-resolved trace element and isotopic analyses of a wide variety of geological materials. Besides benefits to trace element and isotopic studies in ongoing petrologic and environmental studies, the laser will particularly benefit two new geochronologic applications: 1) characterization of intracrystalline U-Th zonation in zircon, to improve precision and accuracy of (U-Th)/He ages and thermochronologies derived from them, and 2) routine measurement of U/Pb ages in single zircon crystals also dated by (U-Th)/He (He-Pb double dating), which is a new and powerful technique for detrital provenance studies of sedimentary rocks. The laser will provide analytical experience and state-of-the-art analyses for graduate and undergraduate students, postdocs, technical staff, and faculty at Yale, as well as for visiting researchers performing (U-Th)/He and ICP-MS analyses including undergraduate participating in summer He dating workshops at Yale.
