A cryogenic system for high-precision isotopic analysis of noble gases in rocks and fluids

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The requested equipment is cryogenic pump for separating and concentrating noble gas species into a mass spectrometer, prior of their isotopic analysis. It will complete a regional facility at GEOTOP-UQAM-McGill (Laboratoire GRÀM: Gaz Rares à Montrèal) for high precision analysis of noble gas isotopes in fluids and rocks with applications in both internal and external geodynamics. This facility consists of a high-resolution multi-collection noble gas mass spectrometer, a low-resolution mass spectrometer and an inlet system for the extraction of noble gases from fluids and rocks and their purification prior of their isotopic analysis. The requested cryogenic system will allow improving significantly the analyses of very low-amount isotopes such as 3He, 21Ne, 38Ar and 124,126,128Xe. Noble gases are inert and rare and these two characteristics make them excellent tracers of major geological processes on earth. At GEOTOP, fundamental research topics are focused on past climates, through analyses of noble gases in oceanic pore waters, fluid inclusions trapped in speleothems and Interplanetary Dust Particles. Industrial-supported research is focused on the study of large-scale migration of fluids of economic importance in Quebèc. Future developments will be done in mantle geochemistry (analyses of noble gases in xenoliths) and cosmogenic dating of marine terraces for quantifying past sea level changes. All these topics require the use of the proposed cryogenic instrumentation for improving analysis of low amount isotopes. The equipment will be fully accessible to other researchers and students under my supervision. The equipment will be an excellent training facility for students to learn mass spectrometry and isotope geochemistry.