MRI: Acquisition of a Noble Gas Multi-Collector Mass Spectrometer for Geochronology and Geochemistry Research

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This project will establish a laboratory with state-of-the-art instruments for measuring noble gases in rock, mineral, and water samples, for geochronologic and geochemical studies in Earth, planetary, and environmental science. The facility will enable a wide variety of scientific studies by researchers and students at the University of Arizona and collaborating institutions. Some of the primary goals of these studies will be: 1) to investigate the timing and rates of geologic events and processes using radioisotopic dating, including faulting, magmatism, and erosion, 2) to characterize the behavior of noble gases in minerals to understand the material properties of natural crystals, and 3) to trace the movement and evolution of groundwater and other fluids in the Earth's subsurface. This project will also enable hands-on research training for students who will use the instruments and laboratory, helping them develop the quantitative and technical skills and experience for Earth, planetary, and environmental science.The centerpiece of the laboratory will be a new multi-collector gas-source sector mass spectrometer and sample introduction equipment including devices for extracting gases using resistance (furnace) and laser heating, crushing of fluid-inclusions, and exsolution from fluids. State of the art high-resolution, high-sensitivity, and multi-collection capabilities of the mass spectrometer will enable simultaneous measurement of all isotopes of argon and neon, and helium will be measured by peak-hopping. Important research foci for the instrument will include 1) geo- and thermochronology using the 40Ar/39Ar system for applications in tectonic, detrital, volcanic, and fault-systems; 2) low-temperature 4He/3He thermochronology and understanding helium mobility in minerals; 3) cosmogenic and nucleogenic 21Ne dating for geomorphic applications and for dating secondary minerals like iron oxides; and 4) isotopic compositions and concentrations of noble gases for tracing the fluxes and evolution of subsurface fluid-rock systems. In addition to serving researchers and students at the University of Arizona, Utah State University, and University of Texas El Paso, the facility will also provide analytical services and research experience opportunities for collaborators at a variety of institutions, including universities and liberal arts colleges, through analyses and workshops for diverse cohorts of students.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.