In Situ Potassium-Argon Geochronology Using Fluxed Fusion and a Double Spike
Hurowitz JA1, Hecht MH1, Zimmerman WF1, Neidholdt EL1, Sinha MP1,
Sturhahn W1, Coleman M1, McCleese DJ1, Farley KA1, Eiler JM1, Rossman GR1,
Waltenberg K1
1California Institute of Technology 2 Queensland University
Pasadena, CA,
USA
Brisbane, Australia
Abstract
A
document highlights an Li-based fluxing agent that enables sample
fusion and quantitative Ar-release at relatively low temperatures
(900-1,000 C), readily achievable with current flight resistance furnace
designs. A solid, double spike containing known quantities of Ar-39 and
K-41 was developed that, when added in known amounts to a sample,
enables the extraction of a Ar-40/K-40 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.