On the treatment of concordant uranium-lead ages
On the treatment of concordant uranium-lead ages
复制标题
DOI：
10.1016/s0016-7037(98)00059-3
复制
发表时间：
1998-02-01
影响因子：
5
通讯作者：
Ludwig, KR
中科院分区：
文献类型：
--
作者：
Ludwig, KR
铀-铅分析可以得出一致的 U/Pb 和 Pb/Pb 年龄，可靠性很高，而且通常非常精确；然而，没有普遍接受的方法来指定最佳年龄和年龄误差或评估一致性断言。本文给出了用于这些目的的两种通用方法，一种用于仅需要少量公共 Pb 校正的样品，另一种用于需要大量公共 Pb 校正的样品。 Concordia 年龄（放射源 Pb/U 比率）和 Total-Pb/U 等时线（包含 Pb-204 的三维等时线）都避免了选择最佳父子比率用于 U/Pb 或 Pb/Pb 年龄或等时线的经常可疑的做法，充分利用两种衰变方案，并适应 U 衰变常数中的误差。此外，总 Pb/U 等时线在一次回归中恢复了完整的铀成因 Pb 同位素比值、误差和误差相关性。版权所有 (C) 1998 爱思唯尔科学有限公司
Uranium-lead analyses that yield arguably concordant U/Pb and Pb/Pb ages are highly reliable and often very precise; however, there is no generally accepted way for either assigning a best age and age-error or for evaluating assertions of concordance. Two general methods for these purposes, one for samples requiring only small common Pb corrections, the other for samples requiring large common Pb corrections, are given in this paper. Both the Concordia age (for radiogenic-Pb/U ratios) and the Total-Pb/U isochron (a three-dimensional isochron than includes Pb-204) obviate the often dubious practice of selecting a best parent-daughter ratio to use for a U/Pb or Pb/Pb age or isochron, make optimum use of both decay schemes, and accommodate errors in the U decay constants. In addition, the Total Pb/U isochron recovers the complete set of uranogenic Pb isotope ratios, errors, and error correlations in a single regression. Copyright (C) 1998 Elsevier Science Ltd.