A document highlights an Li-based fluxing agent that enables sample fusion and quantitative Ar-release at relatively low temperatures (900–1,000 ºC), readily achievable with current flight resistance furnace designs. A solid, double spike containing known quantities of 39Ar and 41K was developed that, when added in known amounts to a sample, enables the extraction of a 4040K ratio for age estimation without a sample mass measurement.
The use of a combination of a flux and a double spike as a means of solving the mechanical hurdles to an in situ K-Ar geochronology measurement has never been proposed before. This methodology and instrument design would provide a capability for assessing the ages of rocks and minerals on the surfaces of planets and other rocky terrestrial bodies in the solar system.
This work was done by Joel A. Hurowitz, Michael H. Hecht, Wayne F. Zimmerman, Evan L. Neidholdt, Mahadeva P. Sinha, Wolfgang Sturhahn, Max Coleman, Daniel J. McCleese, Kenneth A. Farley, John M. Eiler, and George R. Rossman of Caltech, and Kathryn Waltenberg of the University of Queensland, Australia, for NASA’s Jet Propulsion Laboratory. NPO-48099