Open Access40 Ar/ 39 Ar Thermochronology for Submilligram Samples Using a Ta Platform Microfurnace, With Illustrations From the Bushveld Complex
Author(s) -
Setera Jacob B.,
Turrin Brent D.,
Herzog Gregory F.,
VanTongeren Jill A.,
Delaney Jeremy S.,
Swisher Carl C.
Publication year - 2020
Publication title -
geochemistry, geophysics, geosystems
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.928
H-Index - 136
ISSN - 1525-2027
DOI - 10.1029/2020gc009182
Subject(s) - geology , thermochronology , pyrometer , anhydrous , mineralogy , plagioclase , geochronology , geochemistry , analytical chemistry (journal) , quartz , paleontology , chemistry , zircon , temperature measurement , physics , organic chemistry , quantum mechanics , chromatography
We present a method for 40 Ar/ 39 Ar step‐heating measurements on anhydrous K‐bearing minerals. Samples placed in dimples on Ta foil platforms are heated indirectly with a laser while temperatures are measured with a two‐color pyrometer. The system provides a simple, inexpensive, and reliable means for the heating of samples as small as a few to tens of micrograms. Results for plagioclase separates from the Rustenburg Layered Suite of the circa 2.06 Ga Bushveld Complex closely match previously published data.