Solution HR- ICP-MS and LA-ICP-MS Facilities for U-Pb, (U-Th)/He, and trace-element analysis
(1) Solution HR- ICP-MS Facility for (U-Th)/He and trace-element analysis
Besides the He noble gas mass-spectrometry laboratory (see above), the facility also houses two Thermo Element2 HR-ICP-MS instruments in a dedicated and fully-renovated laboratory space with climate control, centrally-piped chilled water, and centrally-distributed Ar gas for ICP-MS operation.
One Element2 HR-ICP-MS is use on a daily basis for solution analyses, primarily for (U-Th)/He dating. Following He degassing, samples are analyzed for U, Th, Sm and selected REE at the (U-Th)/He laboratory. This solution-dedicated Element2 has a sample-introduction system consisting of ESI SC-E2 DX autosampler system and a CETAC micrconcentric nebulizer with 50 microliters/minute sample uptake to accommodate fast and automated small-volume sample analysis for U, Th, Sm for (U-Th)/He dating. The precision and sensitivity of the instrument allow the performance of isotopic analyses to better than 0.1% RSD. This instrument was funded by the Department of Energy (DoE) Geothermal Program (award to Stockli).
(2) Excimer LA-HR- ICP-MS Facility for U-Pb and Split Stream (LASS-ICP-MS) trace-element analysis
A second Element2 HR-ICP-MS in Stockli’s laboratory is dedicated to in-situ laser ablation analysis for U-Pb age geo- and thermochronometry, detrital U-Pb-He double dating, and minor and trace-element finger printing in accessory mineral phase. The facility consists of a dedicated magnetic sector, single collector Element2 HR-ICP-MS with an attached Excimer laser ablation system. The laser ablation system used is a PhotonMachine Analyte G.2 Excimer Laser with a large-volume Helex sample cell (http://www.photon-machines.com/laser-ablation/uv-excimer-la). The Analyte G2 has superior optics for spot selection and the Helex cell is characterized by ultra-fast sample washout, allowing for depth-profiling (both U-Pb, [U], etc.). The second Element2 HR-ICP-MS instrument was funded through the Texas State Stars program as part of Stockli’s start up. For data reduction we use Iolite (on an IGOR Pro platform). The LA-HR-ICP-MS facility is managed by Lisa Stockli.