Extinct 244Pu in Ancient Zircons
Abstract
We have found evidence, in the form of fissiogenic xenon isotopes, for in situ decay of 244Pu in individual 4.1- to 4.2-billion-year-old zircons from the Jack Hills region of Western Australia. Because of its short half-life, 82 million years, 244Pu was extinct within 600 million years of Earth's formation. Detrital zircons are the only known relics to have survived from this period, and a study of their Pu geochemistry will allow us to date ancient metamorphic events and determine the terrestrial Pu/U ratio for comparison with the solar ratio.
- Publication:
-
Science
- Pub Date:
- October 2004
- DOI:
- 10.1126/science.1101014
- Bibcode:
- 2004Sci...306...89T
- Keywords:
-
- GEOCHEM PHYS