Upgrade of noble gas facility for (U-Th)-He capability

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We plan to upgrade our existing VG5400 noble gas mass spectrometer and extraction line, which is now used only for argon-argon geochronology, to permit analysis of helium from minerals such as apatite and zircon for use in (U-Th)-He dating.  The existing mass spectrometer is designed for not only argon and helium isotopic analysis but also a wide range of other noble gases; however, we require a dedicated extraction line for liberating and purifying helium from mineral grains for (U-Th)-He dating.  The (U-Th)-He dating method yields information on when a rock mass last cooled through temperatures as low as 75 degrees Centigrade (e.g., during late uplift and erosion of a mountain range, or during cooling of a volcanic rock unit) or was last heated above these relatively low temperatures (e.g., during the formation of a mineral deposit by influx of heated, metal-bearing fluids).  Over the past decade it has therefore become a very critical tool for studies of thermochronology, i.e., research into the thermal history of mountain belts, volcanic successions and mineral deposits.  Only one other laboratory in Canada (at Dalhousie University) presently has the ability to carry out (U-Th)-He dating.  There is a very wide range of exciting applications of the (U-Th)-He dating method within a young orogenic belt such as the Cordillera of western Canada, and acquiring the capability of doing this type of work at the University of British Columbia will have a major impact on the research of numerous researchers at UBC and in other research institutions in western Canada.