| Titre | Synthesis and purification of 205 Pb for U - Pb geochronology |
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| Auteur | Parrish, R R; Krogh, T E |
| Source | New Developments and Applications in Isotope Geoscience; Chemical Geology (Isotope Geoscience Section) vol. 66, 1987 p. 103-110, https://doi.org/10.1016/0168-9622(87)90033-9 |
| Année | 1987 |
| Séries alt. | Commission géologique du Canada, Contributions aux publications extérieures 42786 |
| Éditeur | Elsevier BV |
| Document | publication en série |
| Lang. | anglais |
| DOI | https://doi.org/10.1016/0168-9622(87)90033-9 |
| Media | papier; en ligne; numérique |
| Formats | pdf |
| Sujets | méthodes analytiques; datation au uranium-plomb; rapports des isotopes de plomb; isotopes; datation radiométrique; minéraux radioactifs; géochronologie |
| Résumé | (disponible en anglais seulement)
205Pb is a synthetic isotope of great utility in U-Pb geochronology, but it has never been widely available in a purified, useable form. We have successfully
completed two production runs with a total yield of ~100µg 205Pb. The isotope was produced by 24-27-MeV proton irradiation using cyclotron facilities of Atomic Energy of Canada Limited in Vancouver. The production path utilises an enriched 206Ph
target and optimizes p,2n reactions to form 205Bi which decays with a 15.3-day half-life to 205Pb. Following irradiation and target stripping, the 205Bi was purified using solvent extraction and subsequent resin column ion exchangers. After a 6-month
decay period in a Pb-free container, the 205Pb was further purified from residual trace elements and organic material prior to making an isotopic tracer solution. The final 205Pb had only 1.2 ± 1.0 ng of total common Ph; its isotopic composition was
measured as 205Pb206Pb=20-25 and 205Pb204Pb > 106 . This material has been distributed to > 50 U-Pb geochronology laboratories worldwide. Its use is expected to considerably increase productivity and technology levels in U-Pb dating. |
| GEOSCAN ID | 122265 |
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