On the age calibration of the geomagnetic polarity timescale
On the age calibration of the geomagnetic polarity timescale
复制标题
DOI：
10.1046/j.1365-246x.1999.00755.x
复制
发表时间：
1999-04-01
影响因子：
2.8
通讯作者：
Lewin, E
中科院分区：
文献类型：
--
作者：
Agrinier, P;Gallet, Y;Lewin, E
如果可以在这些事件之间找到时间顺序关系，则对未注明日期的事件的年龄的了解不是空的。这种时序序列的知识可以通过使用未注明日期的事件的年龄的无信息（均匀）先验概率密度和贝叶斯定理引入时序关系条件来形式化。我们表明，条件概率密度的年龄未知的年龄事件的各种形式的欧拉的β分布。这些分布产生一个未注明日期的事件发生在一个给定的年龄interval.We的概率估计使用这种方法提出适当的概率表示我们的实际知识的测年的磁极反转在新生代。这些表述考虑到了吸积过程中的不规则性和一些校准点的质量所产生的不确定性。这两种类型的不确定性产生了很大的模糊性，在地磁极性时标用于测年目的时，应该考虑到的磁性逆转的年龄。我们建议使用熵函数来量化这些模糊性。
Knowledge of the age of undated events is not null if a time-order relationship can be found among these events. The knowledge of such a time-ordered sequence can be formalized by using non-informative (uniform) prior probability densities for the ages of undated events and Bayes' theorem to introduce the time-order relationship condition. We show that the conditional probability densities of the ages of events of unknown age are given by various forms of Euler's beta distribution. These distributions yield an estimate of the probability for an undated event to occur in a given age interval.We use this method to propose appropriate probabilistic representations of our actual knowledge of the dating of the magnetic polarity reversals during the Cenozoic. These representations take into account the uncertainties arising from irregularities in accretion process and from the quality of a few calibration points. Both types of uncertainties generate large ambiguities in the age of magnetic reversals, which should be taken into consideration when the geomagnetic polarity timescale is used for dating purposes. We propose to use the entropy function to quantify these ambiguities.