Extinct (129)I in halite from a primitive meteorite: evidence for evaporite formation in the early solar system
Halite crystals from the Zag H3-6 chondrite contain essentially pure (monoisotopic) xenon-129 ((129)Xe) produced in the early history of the solar system by the decay of short-lived iodine-129 ((129)I) (half-life = 15.7 million years). Correlated release of (129)Xe and (128)Xe, produced artificially from (127)I by neutron irradiation, corresponds to an initial ((129)I/(127)I) ratio of (1.35 +/- 0.05) x 10(-4), close to the most primitive early solar system value. If the (129)Xe was produced by in situ decay, then the halite formed from an aqueous fluid within 2 million years of the oldest known solar system minerals.
Whitby
J
Department of Earth Sciences, University of Manchester, Manchester M13 9PL, UK. Department of Mineralogy, Natural History Museum, London, SW7 5BD, UK.
Burgess
R
Turner
G
Gilmour
J
Bridges
J