This award will fund the acquisition of a next generation instrument to measure noble gases in rock material for geochronology constraints. Geochronology can be applied to the breadth of anthropology pursuits, planetary sciences and earth process systems from the surface to the deep earth. This University of Alaska Fairbanks laboratory will be a multi-user facility to facilitate the research goals of students, researchers, Alaska’s first people corporations, government agencies, and private economic geology entities. We will pursue many avenues of study including making detrital 40Ar/39Ar geochronology more readily available to the scientific community, investigating some of the problems with dating young (younger than 10,000 years old) volcanic rock products, and increasing the precision of dating the timing of mineralization to assist economic geology interests. The overall project will increase student access to geochronology data sets and train students in advanced geochronology laboratory methods and instrument operations. Student will also be prepared for careers in the earth sciences.
This project will involve the installation, calibration, and operation of a next generation 40Ar/39Ar noble gas multi-collector sector mass spectrometer system. The system includes a custom extraction line, a CO2 laser, and a resistance furnace for degassing rock samples and cleaning up the extracted gases before measurement on the mass spectrometer. The noble gas mass spectrometer will be able to measure the five main argon isotopes concurrently leading to a 10X increase in precision over peak-hoping measurements on a single detector. The high-sensitivity and high resolution capabilities of the new instrumentation will allow measurements to be made on smaller samples sizes with a preference for single-grain applications. The instrument system will be used to further pursue the presence and causes of excess 36Ar in young volcanic rock products. The capabilities of the instrument system will also allow increased single-grain dating throughput allowing for more precise and more time efficient 40Ar/39Ar dating of detrital samples. The modern instrumentation will not only allow more access to geochronology data for students, but will provide a facility designed to enable training of future generations of geochronologists. This project is jointly funded by the EAR Instrumentation & Facilities Program, the Established Program to Stimulate Competitive Research (EPSCoR), and the Major Research Instrumentation Program.
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.
